[v2,3/3] drm/panfrost: Add initial panfrost driver

Submitted by Rob Herring on April 1, 2019, 7:47 a.m.

Details

Message ID 20190401074730.12241-4-robh@kernel.org
State New
Headers show
Series "Initial Panfrost driver" ( rev: 4 3 2 1 ) in DRI devel

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Commit Message

Rob Herring April 1, 2019, 7:47 a.m.
This adds the initial driver for panfrost which supports Arm Mali
Midgard and Bifrost family of GPUs. Currently, only the T860 and
T760 Midgard GPUs have been tested.

v2:
- Add GPU reset on job hangs (Tomeu)
- Add RuntimePM and devfreq support (Tomeu)
- Fix T760 support (Tomeu)
- Add a TODO file (Rob, Tomeu)
- Support multiple in fences (Tomeu)
- Drop support for shared fences (Tomeu)
- Fill in MMU de-init (Rob)
- Move register definitions back to single header (Rob)
- Clean-up hardcoded job submit todos (Rob)
- Implement feature setup based on features/issues (Rob)
- Add remaining Midgard DT compatible strings (Rob)

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Marty E. Plummer <hanetzer@startmail.com>
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Rob Herring <robh@kernel.org>
---
Neil, I've kept your reset support separate for now. Let me know if you
prefer me to squash it or keep it separate.

 drivers/gpu/drm/Kconfig                      |   2 +
 drivers/gpu/drm/Makefile                     |   1 +
 drivers/gpu/drm/panfrost/Kconfig             |  14 +
 drivers/gpu/drm/panfrost/Makefile            |  12 +
 drivers/gpu/drm/panfrost/TODO                |  27 +
 drivers/gpu/drm/panfrost/panfrost_devfreq.c  | 191 +++++++
 drivers/gpu/drm/panfrost/panfrost_devfreq.h  |  14 +
 drivers/gpu/drm/panfrost/panfrost_device.c   | 227 ++++++++
 drivers/gpu/drm/panfrost/panfrost_device.h   | 118 ++++
 drivers/gpu/drm/panfrost/panfrost_drv.c      | 484 ++++++++++++++++
 drivers/gpu/drm/panfrost/panfrost_features.h | 309 +++++++++++
 drivers/gpu/drm/panfrost/panfrost_gem.c      |  92 +++
 drivers/gpu/drm/panfrost/panfrost_gem.h      |  29 +
 drivers/gpu/drm/panfrost/panfrost_gpu.c      | 374 +++++++++++++
 drivers/gpu/drm/panfrost/panfrost_gpu.h      |  19 +
 drivers/gpu/drm/panfrost/panfrost_issues.h   | 176 ++++++
 drivers/gpu/drm/panfrost/panfrost_job.c      | 556 +++++++++++++++++++
 drivers/gpu/drm/panfrost/panfrost_job.h      |  51 ++
 drivers/gpu/drm/panfrost/panfrost_mmu.c      | 366 ++++++++++++
 drivers/gpu/drm/panfrost/panfrost_mmu.h      |  17 +
 drivers/gpu/drm/panfrost/panfrost_regs.h     | 298 ++++++++++
 include/uapi/drm/panfrost_drm.h              | 140 +++++
 22 files changed, 3517 insertions(+)
 create mode 100644 drivers/gpu/drm/panfrost/Kconfig
 create mode 100644 drivers/gpu/drm/panfrost/Makefile
 create mode 100644 drivers/gpu/drm/panfrost/TODO
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_devfreq.c
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_devfreq.h
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_device.c
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_device.h
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_drv.c
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_features.h
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_gem.c
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_gem.h
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_gpu.c
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_gpu.h
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_issues.h
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_job.c
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_job.h
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_mmu.c
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_mmu.h
 create mode 100644 drivers/gpu/drm/panfrost/panfrost_regs.h
 create mode 100644 include/uapi/drm/panfrost_drm.h

--
2.19.1

Patch hide | download patch | download mbox

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index 5e1bc630b885..927cae2468c3 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -337,6 +337,8 @@  source "drivers/gpu/drm/xen/Kconfig"

 source "drivers/gpu/drm/vboxvideo/Kconfig"

+source "drivers/gpu/drm/panfrost/Kconfig"
+
 # Keep legacy drivers last

 menuconfig DRM_LEGACY
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index e630eccb951c..e1255571762d 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -111,3 +111,4 @@  obj-$(CONFIG_DRM_PL111) += pl111/
 obj-$(CONFIG_DRM_TVE200) += tve200/
 obj-$(CONFIG_DRM_XEN) += xen/
 obj-$(CONFIG_DRM_VBOXVIDEO) += vboxvideo/
+obj-$(CONFIG_DRM_PANFROST) += panfrost/
diff --git a/drivers/gpu/drm/panfrost/Kconfig b/drivers/gpu/drm/panfrost/Kconfig
new file mode 100644
index 000000000000..7f5e572daa2d
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/Kconfig
@@ -0,0 +1,14 @@ 
+# SPDX-License-Identifier: GPL-2.0
+
+config DRM_PANFROST
+	tristate "Panfrost (DRM support for ARM Mali Midgard/Bifrost GPUs)"
+	depends on DRM
+	depends on ARM || ARM64 || COMPILE_TEST
+	depends on MMU
+	select DRM_SCHED
+	select IOMMU_SUPPORT
+	select IOMMU_IO_PGTABLE_LPAE
+	select DRM_GEM_SHMEM_HELPER
+	help
+	  DRM driver for ARM Mali Midgard (T6xx, T7xx, T8xx) and
+	  Bifrost (G3x, G5x, G7x) GPUs.
diff --git a/drivers/gpu/drm/panfrost/Makefile b/drivers/gpu/drm/panfrost/Makefile
new file mode 100644
index 000000000000..6de72d13c58f
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/Makefile
@@ -0,0 +1,12 @@ 
+# SPDX-License-Identifier: GPL-2.0
+
+panfrost-y := \
+	panfrost_drv.o \
+	panfrost_device.o \
+	panfrost_devfreq.o \
+	panfrost_gem.o \
+	panfrost_gpu.o \
+	panfrost_job.o \
+	panfrost_mmu.o
+
+obj-$(CONFIG_DRM_PANFROST) += panfrost.o
diff --git a/drivers/gpu/drm/panfrost/TODO b/drivers/gpu/drm/panfrost/TODO
new file mode 100644
index 000000000000..c2e44add37d8
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/TODO
@@ -0,0 +1,27 @@ 
+- Thermal support.
+
+- Bifrost support:
+  - DT bindings (Neil, WIP)
+  - MMU page table format and address space setup
+  - Bifrost specific feature and issue handling
+  - Coherent DMA support
+
+- Support for 2MB pages. The io-pgtable code already supports this. Finishing
+  support involves either copying or adapting the iommu API to handle passing
+  aligned addresses and sizes to the io-pgtable code.
+
+- Per FD address space support. The h/w supports multiple addresses spaces.
+  The hard part is handling when more address spaces are needed than what
+  the h/w provides.
+
+- Support pinning pages on demand (GPU page faults).
+
+- Support userspace controlled GPU virtual addresses. Needed for Vulkan. (Tomeu)
+
+- Support for madvise and a shrinker.
+
+- Compute job support. So called 'compute only' jobs need to be plumbed up to
+  userspace.
+
+- Performance counter support. (Boris)
+
diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
new file mode 100644
index 000000000000..b1c4453f9991
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
@@ -0,0 +1,191 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2019 Collabora ltd. */
+#include <linux/devfreq.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/clk.h>
+#include <linux/regulator/consumer.h>
+
+#include "panfrost_device.h"
+#include "panfrost_features.h"
+#include "panfrost_issues.h"
+#include "panfrost_gpu.h"
+#include "panfrost_regs.h"
+
+static int panfrost_devfreq_target(struct device *dev, unsigned long *freq,
+				   u32 flags)
+{
+	struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
+	struct dev_pm_opp *opp;
+	unsigned long old_clk_rate = pfdev->devfreq.cur_freq;
+	unsigned long target_volt, target_rate;
+	int err;
+
+	opp = devfreq_recommended_opp(dev, freq, flags);
+	if (IS_ERR(opp))
+		return PTR_ERR(opp);
+
+	target_rate = dev_pm_opp_get_freq(opp);
+	target_volt = dev_pm_opp_get_voltage(opp);
+	dev_pm_opp_put(opp);
+
+	if (old_clk_rate == target_rate)
+		return 0;
+
+	/*
+	 * If frequency scaling from low to high, adjust voltage first.
+	 * If frequency scaling from high to low, adjust frequency first.
+	 */
+	if (old_clk_rate < target_rate) {
+		err = regulator_set_voltage(pfdev->regulator, target_volt,
+					    target_volt);
+		if (err) {
+			dev_err(dev, "Cannot set voltage %lu uV\n",
+				target_volt);
+			return err;
+		}
+	}
+
+	err = clk_set_rate(pfdev->clock, target_rate);
+	if (err) {
+		dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
+			err);
+		regulator_set_voltage(pfdev->regulator, pfdev->devfreq.cur_volt,
+				      pfdev->devfreq.cur_volt);
+		return err;
+	}
+
+	if (old_clk_rate > target_rate) {
+		err = regulator_set_voltage(pfdev->regulator, target_volt,
+					    target_volt);
+		if (err)
+			dev_err(dev, "Cannot set voltage %lu uV\n", target_volt);
+	}
+
+	pfdev->devfreq.cur_freq = target_rate;
+	pfdev->devfreq.cur_volt = target_volt;
+
+	return 0;
+}
+
+static void panfrost_devfreq_reset(struct panfrost_device *pfdev)
+{
+	ktime_t now = ktime_get();
+	int i;
+
+	for (i = 0; i < NUM_JOB_SLOTS; i++) {
+		pfdev->devfreq.busy_time[i] = 0;
+		pfdev->devfreq.idle_time[i] = 0;
+		pfdev->devfreq.time_last_update[i] = now;
+	}
+}
+
+static int panfrost_devfreq_get_dev_status(struct device *dev,
+					   struct devfreq_dev_status *status)
+{
+	struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
+	int i;
+
+	status->current_frequency = clk_get_rate(pfdev->clock);
+	status->total_time = ktime_to_ns(ktime_add(pfdev->devfreq.busy_time[0],
+						   pfdev->devfreq.idle_time[0]));
+
+	status->busy_time = 0;
+	for (i = 0; i < NUM_JOB_SLOTS; i++) {
+		status->busy_time += ktime_to_ns(pfdev->devfreq.busy_time[i]);
+	}
+
+	/* We're scheduling only to one core atm, so don't divide for now */
+	//status->busy_time /= NUM_JOB_SLOTS;
+
+	panfrost_devfreq_reset(pfdev);
+
+	dev_dbg(pfdev->dev, "busy %lu total %lu %lu %%\n", status->busy_time,
+		status->total_time,
+		status->busy_time * 100 / status->total_time);
+
+	return 0;
+}
+
+static int panfrost_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
+{
+	struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
+
+	*freq = pfdev->devfreq.cur_freq;
+
+	return 0;
+}
+
+static struct devfreq_dev_profile panfrost_devfreq_profile = {
+	.polling_ms = 10,
+	.target = panfrost_devfreq_target,
+	.get_dev_status = panfrost_devfreq_get_dev_status,
+	.get_cur_freq = panfrost_devfreq_get_cur_freq,
+};
+
+int panfrost_devfreq_init(struct panfrost_device *pfdev)
+{
+	int ret;
+	struct dev_pm_opp *opp;
+
+	ret = dev_pm_opp_of_add_table(&pfdev->pdev->dev);
+	if (ret == -ENODEV) /* Optional, continue without devfreq */
+		return 0;
+
+	panfrost_devfreq_reset(pfdev);
+
+	pfdev->devfreq.cur_freq = clk_get_rate(pfdev->clock);
+
+	opp = devfreq_recommended_opp(&pfdev->pdev->dev, &pfdev->devfreq.cur_freq, 0);
+	if (IS_ERR(opp))
+		return PTR_ERR(opp);
+
+	panfrost_devfreq_profile.initial_freq = pfdev->devfreq.cur_freq;
+	dev_pm_opp_put(opp);
+
+	pfdev->devfreq.devfreq = devm_devfreq_add_device(&pfdev->pdev->dev,
+			&panfrost_devfreq_profile, "simple_ondemand", NULL);
+	if (IS_ERR(pfdev->devfreq.devfreq)) {
+		DRM_DEV_ERROR(&pfdev->pdev->dev, "Couldn't initialize GPU devfreq\n");
+		pfdev->devfreq.devfreq = NULL;
+		return PTR_ERR(pfdev->devfreq.devfreq);
+	}
+
+	return 0;
+}
+
+void panfrost_devfreq_resume(struct panfrost_device *pfdev)
+{
+	if (!pfdev->devfreq.devfreq)
+		return;
+
+	panfrost_devfreq_reset(pfdev);
+	devfreq_resume_device(pfdev->devfreq.devfreq);
+}
+
+void panfrost_devfreq_suspend(struct panfrost_device *pfdev)
+{
+	if (!pfdev->devfreq.devfreq)
+		return;
+
+	devfreq_suspend_device(pfdev->devfreq.devfreq);
+}
+
+void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev, int slot, bool busy)
+{
+	ktime_t now;
+	ktime_t last;
+
+	if (!pfdev->devfreq.devfreq)
+		return;
+
+	now = ktime_get();
+	last = pfdev->devfreq.time_last_update[slot];
+
+	if (busy)
+		pfdev->devfreq.busy_time[slot] += ktime_sub(now, last);
+	else
+		pfdev->devfreq.idle_time[slot] += ktime_sub(now, last);
+
+	pfdev->devfreq.time_last_update[slot] = now;
+}
diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.h b/drivers/gpu/drm/panfrost/panfrost_devfreq.h
new file mode 100644
index 000000000000..1dd7db3b8630
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.h
@@ -0,0 +1,14 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright 2019 Collabora ltd. */
+
+#ifndef __PANFROST_DEVFREQ_H__
+#define __PANFROST_DEVFREQ_H__
+
+int panfrost_devfreq_init(struct panfrost_device *pfdev);
+
+void panfrost_devfreq_resume(struct panfrost_device *pfdev);
+void panfrost_devfreq_suspend(struct panfrost_device *pfdev);
+
+void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev, int slot, bool busy);
+
+#endif /* __PANFROST_DEVFREQ_H__ */
diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c
new file mode 100644
index 000000000000..227ba5202a6f
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_device.c
@@ -0,0 +1,227 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
+
+#include "panfrost_device.h"
+#include "panfrost_devfreq.h"
+#include "panfrost_features.h"
+#include "panfrost_gpu.h"
+#include "panfrost_job.h"
+#include "panfrost_mmu.h"
+
+static int panfrost_clk_init(struct panfrost_device *pfdev)
+{
+	int err;
+	unsigned long rate;
+
+	pfdev->clock = devm_clk_get(pfdev->dev, NULL);
+	if (IS_ERR(pfdev->clock)) {
+		dev_err(pfdev->dev, "get clock failed %ld\n", PTR_ERR(pfdev->clock));
+		return PTR_ERR(pfdev->clock);
+	}
+
+	rate = clk_get_rate(pfdev->clock);
+	dev_info(pfdev->dev, "clock rate = %lu\n", rate);
+
+	err = clk_prepare_enable(pfdev->clock);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static void panfrost_clk_fini(struct panfrost_device *pfdev)
+{
+	clk_disable_unprepare(pfdev->clock);
+}
+
+static int panfrost_regulator_init(struct panfrost_device *pfdev)
+{
+	int ret;
+
+	pfdev->regulator = devm_regulator_get_optional(pfdev->dev, "mali");
+	if (IS_ERR(pfdev->regulator)) {
+		ret = PTR_ERR(pfdev->regulator);
+		pfdev->regulator = NULL;
+		if (ret == -ENODEV)
+			return 0;
+		dev_err(pfdev->dev, "failed to get regulator: %d\n", ret);
+		return ret;
+	}
+
+	ret = regulator_enable(pfdev->regulator);
+	if (ret < 0) {
+		dev_err(pfdev->dev, "failed to enable regulator: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void panfrost_regulator_fini(struct panfrost_device *pfdev)
+{
+	if (pfdev->regulator)
+		regulator_disable(pfdev->regulator);
+}
+
+int panfrost_device_init(struct panfrost_device *pfdev)
+{
+	int err;
+	struct resource *res;
+
+	mutex_init(&pfdev->sched_lock);
+	INIT_LIST_HEAD(&pfdev->scheduled_jobs);
+
+	spin_lock_init(&pfdev->hwaccess_lock);
+
+	err = panfrost_clk_init(pfdev);
+	if (err) {
+		dev_err(pfdev->dev, "clk init failed %d\n", err);
+		return err;
+	}
+
+	err = panfrost_regulator_init(pfdev);
+	if (err) {
+		dev_err(pfdev->dev, "regulator init failed %d\n", err);
+		goto err_out0;
+	}
+
+	res = platform_get_resource(pfdev->pdev, IORESOURCE_MEM, 0);
+	pfdev->iomem = devm_ioremap_resource(pfdev->dev, res);
+	if (IS_ERR(pfdev->iomem)) {
+		dev_err(pfdev->dev, "failed to ioremap iomem\n");
+		err = PTR_ERR(pfdev->iomem);
+		goto err_out1;
+	}
+
+	err = panfrost_gpu_init(pfdev);
+	if (err)
+		goto err_out1;
+
+	err = panfrost_mmu_init(pfdev);
+	if (err)
+		goto err_out2;
+
+	err = panfrost_job_init(pfdev);
+	if (err)
+		goto err_out3;
+
+	/* runtime PM will wake us up later */
+	panfrost_gpu_power_off(pfdev);
+
+	pm_runtime_set_active(pfdev->dev);
+	pm_runtime_get_sync(pfdev->dev);
+	pm_runtime_mark_last_busy(pfdev->dev);
+	pm_runtime_put_autosuspend(pfdev->dev);
+
+	return 0;
+err_out3:
+	panfrost_mmu_fini(pfdev);
+err_out2:
+	panfrost_gpu_fini(pfdev);
+err_out1:
+	panfrost_regulator_fini(pfdev);
+err_out0:
+	panfrost_clk_fini(pfdev);
+	return err;
+}
+
+void panfrost_device_fini(struct panfrost_device *pfdev)
+{
+	panfrost_regulator_fini(pfdev);
+	panfrost_clk_fini(pfdev);
+}
+
+const char *panfrost_exception_name(struct panfrost_device *pfdev, u32 exception_code)
+{
+	switch (exception_code) {
+		/* Non-Fault Status code */
+	case 0x00: return "NOT_STARTED/IDLE/OK";
+	case 0x01: return "DONE";
+	case 0x02: return "INTERRUPTED";
+	case 0x03: return "STOPPED";
+	case 0x04: return "TERMINATED";
+	case 0x08: return "ACTIVE";
+		/* Job exceptions */
+	case 0x40: return "JOB_CONFIG_FAULT";
+	case 0x41: return "JOB_POWER_FAULT";
+	case 0x42: return "JOB_READ_FAULT";
+	case 0x43: return "JOB_WRITE_FAULT";
+	case 0x44: return "JOB_AFFINITY_FAULT";
+	case 0x48: return "JOB_BUS_FAULT";
+	case 0x50: return "INSTR_INVALID_PC";
+	case 0x51: return "INSTR_INVALID_ENC";
+	case 0x52: return "INSTR_TYPE_MISMATCH";
+	case 0x53: return "INSTR_OPERAND_FAULT";
+	case 0x54: return "INSTR_TLS_FAULT";
+	case 0x55: return "INSTR_BARRIER_FAULT";
+	case 0x56: return "INSTR_ALIGN_FAULT";
+	case 0x58: return "DATA_INVALID_FAULT";
+	case 0x59: return "TILE_RANGE_FAULT";
+	case 0x5A: return "ADDR_RANGE_FAULT";
+	case 0x60: return "OUT_OF_MEMORY";
+		/* GPU exceptions */
+	case 0x80: return "DELAYED_BUS_FAULT";
+	case 0x88: return "SHAREABILITY_FAULT";
+		/* MMU exceptions */
+	case 0xC1: return "TRANSLATION_FAULT_LEVEL1";
+	case 0xC2: return "TRANSLATION_FAULT_LEVEL2";
+	case 0xC3: return "TRANSLATION_FAULT_LEVEL3";
+	case 0xC4: return "TRANSLATION_FAULT_LEVEL4";
+	case 0xC8: return "PERMISSION_FAULT";
+	case 0xD1: return "TRANSTAB_BUS_FAULT_LEVEL1";
+	case 0xD2: return "TRANSTAB_BUS_FAULT_LEVEL2";
+	case 0xD3: return "TRANSTAB_BUS_FAULT_LEVEL3";
+	case 0xD4: return "TRANSTAB_BUS_FAULT_LEVEL4";
+	case 0xD8: return "ACCESS_FLAG";
+	}
+
+	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_AARCH64_MMU)) {
+		switch (exception_code) {
+		case 0xC9 ... 0xCF: return "PERMISSION_FAULT";
+		case 0xD9 ... 0xDF: return "ACCESS_FLAG";
+		case 0xE0 ... 0xE7: return "ADDRESS_SIZE_FAULT";
+		case 0xE8 ... 0xEF: return "MEMORY_ATTRIBUTES_FAULT";
+		}
+	}
+
+	return "UNKNOWN";
+}
+
+#ifdef CONFIG_PM
+int panfrost_device_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct panfrost_device *pfdev = platform_get_drvdata(pdev);
+
+	panfrost_gpu_soft_reset(pfdev);
+
+	/* TODO: Re-enable all other address spaces */
+	panfrost_gpu_power_on(pfdev);
+	panfrost_mmu_enable(pfdev, 0);
+	panfrost_job_enable_interrupts(pfdev);
+	panfrost_devfreq_resume(pfdev);
+
+	return 0;
+}
+
+int panfrost_device_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct panfrost_device *pfdev = platform_get_drvdata(pdev);
+
+	panfrost_devfreq_suspend(pfdev);
+
+	if (!panfrost_job_is_idle(pfdev))
+		return -EBUSY;
+
+	panfrost_gpu_power_off(pfdev);
+
+	return 0;
+}
+#endif
diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h
new file mode 100644
index 000000000000..f92011d05cc0
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_device.h
@@ -0,0 +1,118 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+
+#ifndef __PANFROST_DEVICE_H__
+#define __PANFROST_DEVICE_H__
+
+#include <linux/spinlock.h>
+#include <drm/drm_device.h>
+#include <drm/drm_mm.h>
+#include <drm/gpu_scheduler.h>
+
+struct panfrost_device;
+struct panfrost_mmu;
+struct panfrost_job_slot;
+struct panfrost_job;
+
+#define NUM_JOB_SLOTS 3
+
+struct panfrost_features {
+	u16 id;
+	u16 revision;
+
+	u64 shader_present;
+	u64 tiler_present;
+	u64 l2_present;
+	u64 stack_present;
+	u32 as_present;
+	u32 js_present;
+
+	u32 l2_features;
+	u32 core_features;
+	u32 tiler_features;
+	u32 mem_features;
+	u32 mmu_features;
+	u32 thread_features;
+	u32 max_threads;
+	u32 thread_max_workgroup_sz;
+	u32 thread_max_barrier_sz;
+	u32 coherency_features;
+	u32 texture_features[4];
+	u32 js_features[16];
+
+	u32 nr_core_groups;
+
+	unsigned long hw_features[64 / BITS_PER_LONG];
+	unsigned long hw_issues[64 / BITS_PER_LONG];
+};
+
+struct panfrost_device {
+	struct device *dev;
+	struct drm_device *ddev;
+	struct platform_device *pdev;
+
+	spinlock_t hwaccess_lock;
+
+	struct drm_mm mm;
+	spinlock_t mm_lock;
+
+	void __iomem *iomem;
+	struct clk *clock;
+	struct regulator *regulator;
+
+	struct panfrost_features features;
+
+	struct panfrost_mmu *mmu;
+	struct panfrost_job_slot *js;
+
+	struct panfrost_job *jobs[NUM_JOB_SLOTS];
+	struct list_head scheduled_jobs;
+
+	struct mutex sched_lock;
+
+	struct {
+		struct devfreq *devfreq;
+		struct thermal_cooling_device *cooling;
+		unsigned long cur_freq;
+		unsigned long cur_volt;
+		ktime_t busy_time[NUM_JOB_SLOTS];
+		ktime_t idle_time[NUM_JOB_SLOTS];
+		ktime_t time_last_update[NUM_JOB_SLOTS];
+	} devfreq;
+};
+
+struct panfrost_file_priv {
+	struct panfrost_device *pfdev;
+
+	struct drm_sched_entity sched_entity[NUM_JOB_SLOTS];
+};
+
+static inline struct panfrost_device *to_panfrost_device(struct drm_device *ddev)
+{
+	return ddev->dev_private;
+}
+
+static inline int panfrost_model_cmp(struct panfrost_device *pfdev, s32 id)
+{
+	s32 match_id = pfdev->features.id;
+
+	if (match_id & 0xf000)
+		match_id &= 0xf00f;
+	return match_id - id;
+}
+
+static inline bool panfrost_model_eq(struct panfrost_device *pfdev, s32 id)
+{
+	return !panfrost_model_cmp(pfdev, id);
+}
+
+int panfrost_device_init(struct panfrost_device *pfdev);
+void panfrost_device_fini(struct panfrost_device *pfdev);
+
+int panfrost_device_resume(struct device *dev);
+int panfrost_device_suspend(struct device *dev);
+
+const char *panfrost_exception_name(struct panfrost_device *pfdev, u32 exception_code);
+
+#endif
diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c
new file mode 100644
index 000000000000..57a99032bcc6
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
@@ -0,0 +1,484 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
+/* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
+/* Copyright 2019 Collabora ltd. */
+
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/pagemap.h>
+#include <linux/pm_runtime.h>
+#include <drm/panfrost_drm.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_ioctl.h>
+#include <drm/drm_syncobj.h>
+#include <drm/drm_utils.h>
+
+#include "panfrost_device.h"
+#include "panfrost_devfreq.h"
+#include "panfrost_gem.h"
+#include "panfrost_mmu.h"
+#include "panfrost_job.h"
+#include "panfrost_gpu.h"
+
+static int panfrost_ioctl_get_param(struct drm_device *ddev, void *data, struct drm_file *file)
+{
+	struct drm_panfrost_get_param *param = data;
+	struct panfrost_device *pfdev = ddev->dev_private;
+
+	if (param->pad != 0)
+		return -EINVAL;
+
+	switch (param->param) {
+	case DRM_PANFROST_PARAM_GPU_ID:
+		param->value = pfdev->features.id;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int panfrost_ioctl_create_bo(struct drm_device *dev, void *data,
+		struct drm_file *file)
+{
+	int ret;
+	struct drm_gem_shmem_object *shmem;
+	struct drm_panfrost_create_bo *args = data;
+
+	if (!args->size || args->flags)
+		return -EINVAL;
+
+	shmem = drm_gem_shmem_create_with_handle(file, dev, args->size,
+						 &args->handle);
+	if (IS_ERR(shmem))
+		return PTR_ERR(shmem);
+
+	ret = panfrost_mmu_map(to_panfrost_bo(&shmem->base));
+	if (ret)
+		goto err_free;
+
+	args->offset = to_panfrost_bo(&shmem->base)->node.start << PAGE_SHIFT;
+
+	return 0;
+
+err_free:
+	drm_gem_object_put_unlocked(&shmem->base);
+	return ret;
+}
+
+/**
+ * panfrost_lookup_bos() - Sets up job->bo[] with the GEM objects
+ * referenced by the job.
+ * @dev: DRM device
+ * @file_priv: DRM file for this fd
+ * @args: IOCTL args
+ * @job: job being set up
+ *
+ * Resolve handles from userspace to BOs and attach them to job.
+ *
+ * Note that this function doesn't need to unreference the BOs on
+ * failure, because that will happen at panfrost_job_cleanup() time.
+ */
+static int
+panfrost_lookup_bos(struct drm_device *dev,
+		  struct drm_file *file_priv,
+		  struct drm_panfrost_submit *args,
+		  struct panfrost_job *job)
+{
+	u32 *handles;
+	int ret = 0;
+
+	job->bo_count = args->bo_handle_count;
+
+	if (!job->bo_count)
+		return 0;
+
+	job->bos = kvmalloc_array(job->bo_count,
+				  sizeof(struct drm_gem_object *),
+				  GFP_KERNEL | __GFP_ZERO);
+	if (!job->bos)
+		return -ENOMEM;
+
+	job->implicit_fences = kvmalloc_array(job->bo_count,
+				  sizeof(struct dma_fence *),
+				  GFP_KERNEL | __GFP_ZERO);
+	if (!job->implicit_fences)
+		return -ENOMEM;
+
+	handles = kvmalloc_array(job->bo_count, sizeof(u32), GFP_KERNEL);
+	if (!handles) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	if (copy_from_user(handles,
+			   (void __user *)(uintptr_t)args->bo_handles,
+			   job->bo_count * sizeof(u32))) {
+		ret = -EFAULT;
+		DRM_DEBUG("Failed to copy in GEM handles\n");
+		goto fail;
+	}
+
+	ret = drm_gem_objects_lookup(file_priv, handles, job->bo_count, job->bos);
+
+fail:
+	kvfree(handles);
+	return ret;
+}
+
+/**
+ * panfrost_copy_in_sync() - Sets up job->in_fences[] with the sync objects
+ * referenced by the job.
+ * @dev: DRM device
+ * @file_priv: DRM file for this fd
+ * @args: IOCTL args
+ * @job: job being set up
+ *
+ * Resolve syncobjs from userspace to fences and attach them to job.
+ *
+ * Note that this function doesn't need to unreference the fences on
+ * failure, because that will happen at panfrost_job_cleanup() time.
+ */
+static int
+panfrost_copy_in_sync(struct drm_device *dev,
+		  struct drm_file *file_priv,
+		  struct drm_panfrost_submit *args,
+		  struct panfrost_job *job)
+{
+	u32 *handles;
+	int ret = 0;
+	int i;
+
+	job->in_fence_count = args->in_sync_count;
+
+	if (!job->in_fence_count)
+		return 0;
+
+	job->in_fences = kvmalloc_array(job->in_fence_count,
+				  sizeof(struct drm_panfrost_gem_object *),
+				  GFP_KERNEL | __GFP_ZERO);
+	if (!job->in_fences) {
+		DRM_DEBUG("Failed to allocate job in fences\n");
+		return -ENOMEM;
+	}
+
+	handles = kvmalloc_array(job->in_fence_count, sizeof(u32), GFP_KERNEL);
+	if (!handles) {
+		ret = -ENOMEM;
+		DRM_DEBUG("Failed to allocate incoming syncobj handles\n");
+		goto fail;
+	}
+
+	if (copy_from_user(handles,
+			   (void __user *)(uintptr_t)args->in_syncs,
+			   job->in_fence_count * sizeof(u32))) {
+		ret = -EFAULT;
+		DRM_DEBUG("Failed to copy in syncobj handles\n");
+		goto fail;
+	}
+
+	for (i = 0; i < job->in_fence_count; i++) {
+		ret = drm_syncobj_find_fence(file_priv, handles[i], 0, 0,
+					     &job->in_fences[i]);
+		if (ret == -EINVAL)
+			goto fail;
+	}
+
+fail:
+	kvfree(handles);
+	return ret;
+}
+
+static int panfrost_ioctl_submit(struct drm_device *dev, void *data,
+		struct drm_file *file)
+{
+	struct panfrost_device *pfdev = dev->dev_private;
+	struct drm_panfrost_submit *args = data;
+	struct drm_syncobj *sync_out;
+	struct panfrost_job *job;
+	int ret = 0;
+
+	job = kcalloc(1, sizeof(*job), GFP_KERNEL);
+	if (!job)
+		return -ENOMEM;
+
+	kref_init(&job->refcount);
+
+	job->pfdev = pfdev;
+	job->jc = args->jc;
+	job->requirements = args->requirements;
+	job->flush_id = panfrost_gpu_get_latest_flush_id(pfdev);
+	job->file_priv = file->driver_priv;
+
+	ret = panfrost_copy_in_sync(dev, file, args, job);
+	if (ret)
+		goto fail;
+
+	ret = panfrost_lookup_bos(dev, file, args, job);
+	if (ret)
+		goto fail;
+
+	ret = panfrost_job_push(job);
+	if (ret)
+		goto fail;
+
+	/* Update the return sync object for the job */
+	sync_out = drm_syncobj_find(file, args->out_sync);
+	if (sync_out) {
+		drm_syncobj_replace_fence(sync_out, job->render_done_fence);
+		drm_syncobj_put(sync_out);
+	}
+
+fail:
+	panfrost_job_put(job);
+
+	return ret;
+}
+
+static int
+panfrost_ioctl_wait_bo(struct drm_device *dev, void *data,
+		       struct drm_file *file_priv)
+{
+	long ret;
+	struct drm_panfrost_wait_bo *args = data;
+	struct drm_gem_object *gem_obj;
+	unsigned long timeout = drm_timeout_abs_to_jiffies(args->timeout_ns);
+
+	if (args->pad)
+		return -EINVAL;
+
+	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
+	if (!gem_obj)
+		return -ENOENT;
+
+	ret = reservation_object_wait_timeout_rcu(gem_obj->resv, true,
+						  true, timeout);
+	if (!ret)
+		ret = timeout ? -ETIMEDOUT : -EBUSY;
+
+	drm_gem_object_put_unlocked(gem_obj);
+
+	return ret;
+}
+
+static int panfrost_ioctl_mmap_bo(struct drm_device *dev, void *data,
+		      struct drm_file *file_priv)
+{
+	struct drm_panfrost_mmap_bo *args = data;
+	struct drm_gem_object *gem_obj;
+	int ret;
+
+	if (args->flags != 0) {
+		DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
+		return -EINVAL;
+	}
+
+	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
+	if (!gem_obj) {
+		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
+		return -ENOENT;
+	}
+
+	ret = drm_gem_create_mmap_offset(gem_obj);
+	if (ret == 0)
+		args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
+	drm_gem_object_put_unlocked(gem_obj);
+
+	return ret;
+}
+
+static int panfrost_ioctl_get_bo_offset(struct drm_device *dev, void *data,
+			    struct drm_file *file_priv)
+{
+	struct drm_panfrost_get_bo_offset *args = data;
+	struct drm_gem_object *gem_obj;
+	struct panfrost_gem_object *bo;
+
+	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
+	if (!gem_obj) {
+		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
+		return -ENOENT;
+	}
+	bo = to_panfrost_bo(gem_obj);
+
+	args->offset = bo->node.start << PAGE_SHIFT;
+
+	drm_gem_object_put_unlocked(gem_obj);
+	return 0;
+}
+
+static int
+panfrost_open(struct drm_device *dev, struct drm_file *file)
+{
+	struct panfrost_device *pfdev = dev->dev_private;
+	struct panfrost_file_priv *panfrost_priv;
+
+	panfrost_priv = kzalloc(sizeof(*panfrost_priv), GFP_KERNEL);
+	if (!panfrost_priv)
+		return -ENOMEM;
+
+	panfrost_priv->pfdev = pfdev;
+	file->driver_priv = panfrost_priv;
+
+	return panfrost_job_open(panfrost_priv);
+}
+
+static void
+panfrost_postclose(struct drm_device *dev, struct drm_file *file)
+{
+	struct panfrost_file_priv *panfrost_priv = file->driver_priv;
+
+	panfrost_job_close(panfrost_priv);
+
+	kfree(panfrost_priv);
+}
+
+/* DRM_AUTH is required on SUBMIT for now, while all clients share a single
+ * address space.  Note that render nodes would be able to submit jobs that
+ * could access BOs from clients authenticated with the master node.
+ */
+static const struct drm_ioctl_desc panfrost_drm_driver_ioctls[] = {
+#define PANFROST_IOCTL(n, func, flags) \
+	DRM_IOCTL_DEF_DRV(PANFROST_##n, panfrost_ioctl_##func, flags)
+
+	PANFROST_IOCTL(SUBMIT,		submit,		DRM_RENDER_ALLOW | DRM_AUTH),
+	PANFROST_IOCTL(WAIT_BO,		wait_bo,	DRM_RENDER_ALLOW),
+	PANFROST_IOCTL(CREATE_BO,	create_bo,	DRM_RENDER_ALLOW),
+	PANFROST_IOCTL(MMAP_BO,		mmap_bo,	DRM_RENDER_ALLOW),
+	PANFROST_IOCTL(GET_PARAM,	get_param,	DRM_RENDER_ALLOW),
+	PANFROST_IOCTL(GET_BO_OFFSET,	get_bo_offset,	DRM_RENDER_ALLOW),
+};
+
+DEFINE_DRM_GEM_SHMEM_FOPS(panfrost_drm_driver_fops);
+
+static struct drm_driver panfrost_drm_driver = {
+	.driver_features	= DRIVER_RENDER | DRIVER_GEM | DRIVER_PRIME |
+				  DRIVER_SYNCOBJ,
+	.open			= panfrost_open,
+	.postclose		= panfrost_postclose,
+	.ioctls			= panfrost_drm_driver_ioctls,
+	.num_ioctls		= ARRAY_SIZE(panfrost_drm_driver_ioctls),
+	.fops			= &panfrost_drm_driver_fops,
+	.name			= "panfrost",
+	.desc			= "panfrost DRM",
+	.date			= "20180908",
+	.major			= 1,
+	.minor			= 0,
+
+	.gem_create_object	= panfrost_gem_create_object,
+	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd,
+	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle,
+	.gem_prime_import_sg_table = panfrost_gem_prime_import_sg_table,
+	.gem_prime_mmap		= drm_gem_prime_mmap,
+};
+
+static int panfrost_probe(struct platform_device *pdev)
+{
+	struct panfrost_device *pfdev;
+	struct drm_device *ddev;
+	int err;
+
+	pfdev = devm_kzalloc(&pdev->dev, sizeof(*pfdev), GFP_KERNEL);
+	if (!pfdev)
+		return -ENOMEM;
+
+	pfdev->pdev = pdev;
+	pfdev->dev = &pdev->dev;
+
+	platform_set_drvdata(pdev, pfdev);
+
+	/* Allocate and initialze the DRM device. */
+	ddev = drm_dev_alloc(&panfrost_drm_driver, &pdev->dev);
+	if (IS_ERR(ddev))
+		return PTR_ERR(ddev);
+
+	ddev->dev_private = pfdev;
+	pfdev->ddev = ddev;
+
+	spin_lock_init(&pfdev->mm_lock);
+
+	/* 4G enough for now. can be 48-bit */
+	drm_mm_init(&pfdev->mm, SZ_32M >> PAGE_SHIFT, SZ_4G);
+
+	pm_runtime_use_autosuspend(pfdev->dev);
+	pm_runtime_set_autosuspend_delay(pfdev->dev, 50); /* ~3 frames */
+	pm_runtime_enable(pfdev->dev);
+
+	err = panfrost_device_init(pfdev);
+	if (err) {
+		dev_err(&pdev->dev, "Fatal error during GPU init\n");
+		goto err_out0;
+	}
+
+	err = panfrost_devfreq_init(pfdev);
+	if (err) {
+		dev_err(&pdev->dev, "Fatal error during devfreq init\n");
+		goto err_out1;
+	}
+
+	/*
+	 * Register the DRM device with the core and the connectors with
+	 * sysfs
+	 */
+	err = drm_dev_register(ddev, 0);
+	if (err < 0)
+		goto err_out1;
+
+	return 0;
+
+err_out1:
+	panfrost_device_fini(pfdev);
+err_out0:
+	drm_dev_put(ddev);
+	return err;
+}
+
+static int panfrost_remove(struct platform_device *pdev)
+{
+	struct panfrost_device *pfdev = platform_get_drvdata(pdev);
+	struct drm_device *ddev = pfdev->ddev;
+
+	drm_dev_unregister(ddev);
+	pm_runtime_get_sync(pfdev->dev);
+	pm_runtime_put_sync_autosuspend(pfdev->dev);
+	pm_runtime_disable(pfdev->dev);
+	panfrost_device_fini(pfdev);
+	drm_dev_put(ddev);
+	return 0;
+}
+
+static const struct of_device_id dt_match[] = {
+	{ .compatible = "arm,mali-t604" },
+	{ .compatible = "arm,mali-t624" },
+	{ .compatible = "arm,mali-t628" },
+	{ .compatible = "arm,mali-t720" },
+	{ .compatible = "arm,mali-t760" },
+	{ .compatible = "arm,mali-t820" },
+	{ .compatible = "arm,mali-t830" },
+	{ .compatible = "arm,mali-t860" },
+	{ .compatible = "arm,mali-t880" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, dt_match);
+
+static const struct dev_pm_ops panfrost_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
+	SET_RUNTIME_PM_OPS(panfrost_device_suspend, panfrost_device_resume, NULL)
+};
+
+static struct platform_driver panfrost_driver = {
+	.probe		= panfrost_probe,
+	.remove		= panfrost_remove,
+	.driver		= {
+		.name	= "panfrost",
+		.pm	= &panfrost_pm_ops,
+		.of_match_table = dt_match,
+	},
+};
+module_platform_driver(panfrost_driver);
+
+MODULE_AUTHOR("Panfrost Project Developers");
+MODULE_DESCRIPTION("Panfrost DRM Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpu/drm/panfrost/panfrost_features.h b/drivers/gpu/drm/panfrost/panfrost_features.h
new file mode 100644
index 000000000000..5056777c7744
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_features.h
@@ -0,0 +1,309 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* (C) COPYRIGHT 2014-2018 ARM Limited. All rights reserved. */
+/* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
+#ifndef __PANFROST_FEATURES_H__
+#define __PANFROST_FEATURES_H__
+
+#include <linux/bitops.h>
+
+#include "panfrost_device.h"
+
+enum panfrost_hw_feature {
+	HW_FEATURE_JOBCHAIN_DISAMBIGUATION,
+	HW_FEATURE_PWRON_DURING_PWROFF_TRANS,
+	HW_FEATURE_XAFFINITY,
+	HW_FEATURE_OUT_OF_ORDER_EXEC,
+	HW_FEATURE_MRT,
+	HW_FEATURE_BRNDOUT_CC,
+	HW_FEATURE_INTERPIPE_REG_ALIASING,
+	HW_FEATURE_LD_ST_TILEBUFFER,
+	HW_FEATURE_MSAA_16X,
+	HW_FEATURE_32_BIT_UNIFORM_ADDRESS,
+	HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL,
+	HW_FEATURE_OPTIMIZED_COVERAGE_MASK,
+	HW_FEATURE_T7XX_PAIRING_RULES,
+	HW_FEATURE_LD_ST_LEA_TEX,
+	HW_FEATURE_LINEAR_FILTER_FLOAT,
+	HW_FEATURE_WORKGROUP_ROUND_MULTIPLE_OF_4,
+	HW_FEATURE_IMAGES_IN_FRAGMENT_SHADERS,
+	HW_FEATURE_TEST4_DATUM_MODE,
+	HW_FEATURE_NEXT_INSTRUCTION_TYPE,
+	HW_FEATURE_BRNDOUT_KILL,
+	HW_FEATURE_WARPING,
+	HW_FEATURE_V4,
+	HW_FEATURE_FLUSH_REDUCTION,
+	HW_FEATURE_PROTECTED_MODE,
+	HW_FEATURE_COHERENCY_REG,
+	HW_FEATURE_PROTECTED_DEBUG_MODE,
+	HW_FEATURE_AARCH64_MMU,
+	HW_FEATURE_TLS_HASHING,
+	HW_FEATURE_THREAD_GROUP_SPLIT,
+	HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG,
+};
+
+#define hw_features_t600 (\
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
+	BIT_ULL(HW_FEATURE_V4))
+
+#define hw_features_t620 (\
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
+	BIT_ULL(HW_FEATURE_V4))
+
+#define hw_features_t720 (\
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
+	BIT_ULL(HW_FEATURE_OPTIMIZED_COVERAGE_MASK) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
+	BIT_ULL(HW_FEATURE_WORKGROUP_ROUND_MULTIPLE_OF_4) | \
+	BIT_ULL(HW_FEATURE_WARPING) | \
+	BIT_ULL(HW_FEATURE_V4))
+
+
+#define hw_features_t760 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_MSAA_16X) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT))
+
+// T860
+#define hw_features_t860 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_MSAA_16X) | \
+	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT))
+
+#define hw_features_t880 hw_features_t860
+
+#define hw_features_t830 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_WARPING) | \
+	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT))
+
+#define hw_features_t820 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_WARPING) | \
+	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT))
+
+#define hw_features_g71 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_WARPING) | \
+	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_MSAA_16X) | \
+	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
+	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
+	BIT_ULL(HW_FEATURE_COHERENCY_REG))
+
+#define hw_features_g72 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_WARPING) | \
+	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_MSAA_16X) | \
+	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
+	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
+	BIT_ULL(HW_FEATURE_COHERENCY_REG))
+
+#define hw_features_g51 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_WARPING) | \
+	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_MSAA_16X) | \
+	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
+	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
+	BIT_ULL(HW_FEATURE_COHERENCY_REG))
+
+#define hw_features_g52 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_WARPING) | \
+	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_MSAA_16X) | \
+	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
+	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
+	BIT_ULL(HW_FEATURE_COHERENCY_REG))
+
+#define hw_features_g76 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_WARPING) | \
+	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_MSAA_16X) | \
+	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
+	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
+	BIT_ULL(HW_FEATURE_COHERENCY_REG) | \
+	BIT_ULL(HW_FEATURE_AARCH64_MMU) | \
+	BIT_ULL(HW_FEATURE_TLS_HASHING) | \
+	BIT_ULL(HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG))
+
+#define hw_features_g31 (\
+	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
+	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
+	BIT_ULL(HW_FEATURE_XAFFINITY) | \
+	BIT_ULL(HW_FEATURE_WARPING) | \
+	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
+	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
+	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
+	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
+	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
+	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
+	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
+	BIT_ULL(HW_FEATURE_MRT) | \
+	BIT_ULL(HW_FEATURE_MSAA_16X) | \
+	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
+	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
+	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
+	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
+	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
+	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
+	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
+	BIT_ULL(HW_FEATURE_COHERENCY_REG) | \
+	BIT_ULL(HW_FEATURE_AARCH64_MMU) | \
+	BIT_ULL(HW_FEATURE_TLS_HASHING) | \
+	BIT_ULL(HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG))
+
+static inline bool panfrost_has_hw_feature(struct panfrost_device *pfdev,
+					   enum panfrost_hw_feature feat)
+{
+	return test_bit(feat, pfdev->features.hw_features);
+}
+
+#endif
diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c b/drivers/gpu/drm/panfrost/panfrost_gem.c
new file mode 100644
index 000000000000..31f13f49277a
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_gem.c
@@ -0,0 +1,92 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/dma-buf.h>
+#include <linux/dma-mapping.h>
+
+#include <drm/panfrost_drm.h>
+#include "panfrost_device.h"
+#include "panfrost_gem.h"
+#include "panfrost_mmu.h"
+
+/* Called DRM core on the last userspace/kernel unreference of the
+ * BO.
+ */
+void panfrost_gem_free_object(struct drm_gem_object *obj)
+{
+	struct panfrost_gem_object *bo = to_panfrost_bo(obj);
+	struct panfrost_device *pfdev = obj->dev->dev_private;
+
+	panfrost_mmu_unmap(bo);
+
+	spin_lock(&pfdev->mm_lock);
+	drm_mm_remove_node(&bo->node);
+	spin_unlock(&pfdev->mm_lock);
+
+	drm_gem_shmem_free_object(obj);
+}
+
+static const struct drm_gem_object_funcs panfrost_gem_funcs = {
+	.free = panfrost_gem_free_object,
+	.print_info = drm_gem_shmem_print_info,
+	.pin = drm_gem_shmem_pin,
+	.unpin = drm_gem_shmem_unpin,
+	.get_sg_table = drm_gem_shmem_get_sg_table,
+	.vmap = drm_gem_shmem_vmap,
+	.vunmap = drm_gem_shmem_vunmap,
+	.vm_ops = &drm_gem_shmem_vm_ops,
+};
+
+/**
+ * panfrost_gem_create_object - Implementation of driver->gem_create_object.
+ * @dev: DRM device
+ * @size: Size in bytes of the memory the object will reference
+ *
+ * This lets the GEM helpers allocate object structs for us, and keep
+ * our BO stats correct.
+ */
+struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t size)
+{
+	int ret;
+	struct panfrost_device *pfdev = dev->dev_private;
+	struct panfrost_gem_object *obj;
+
+	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
+	if (!obj)
+		return NULL;
+
+	obj->base.base.funcs = &panfrost_gem_funcs;
+
+	spin_lock(&pfdev->mm_lock);
+	ret = drm_mm_insert_node(&pfdev->mm, &obj->node,
+				 roundup(size, PAGE_SIZE) >> PAGE_SHIFT);
+	spin_unlock(&pfdev->mm_lock);
+	if (ret)
+		goto free_obj;
+
+	return &obj->base.base;
+
+free_obj:
+	kfree(obj);
+	return ERR_PTR(ret);
+}
+
+struct drm_gem_object *
+panfrost_gem_prime_import_sg_table(struct drm_device *dev,
+				   struct dma_buf_attachment *attach,
+				   struct sg_table *sgt)
+{
+	struct drm_gem_object *obj;
+	struct panfrost_gem_object *pobj;
+
+	obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
+	pobj = to_panfrost_bo(obj);
+
+	obj->resv = attach->dmabuf->resv;
+
+	panfrost_mmu_map(pobj);
+
+	return obj;
+}
diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.h b/drivers/gpu/drm/panfrost/panfrost_gem.h
new file mode 100644
index 000000000000..045000eb5fcf
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_gem.h
@@ -0,0 +1,29 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+
+#ifndef __PANFROST_GEM_H__
+#define __PANFROST_GEM_H__
+
+#include <drm/drm_gem_shmem_helper.h>
+#include <drm/drm_mm.h>
+
+struct panfrost_gem_object {
+	struct drm_gem_shmem_object base;
+
+	struct drm_mm_node node;
+};
+
+static inline
+struct  panfrost_gem_object *to_panfrost_bo(struct drm_gem_object *obj)
+{
+	return container_of(to_drm_gem_shmem_obj(obj), struct panfrost_gem_object, base);
+}
+
+struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t size);
+
+struct drm_gem_object *
+panfrost_gem_prime_import_sg_table(struct drm_device *dev,
+				   struct dma_buf_attachment *attach,
+				   struct sg_table *sgt);
+
+#endif /* __PANFROST_GEM_H__ */
diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.c b/drivers/gpu/drm/panfrost/panfrost_gpu.c
new file mode 100644
index 000000000000..867e2ba3a761
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_gpu.c
@@ -0,0 +1,374 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
+/* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
+/* Copyright 2019 Collabora ltd. */
+#include <linux/bitmap.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/platform_device.h>
+
+#include "panfrost_device.h"
+#include "panfrost_features.h"
+#include "panfrost_issues.h"
+#include "panfrost_gpu.h"
+#include "panfrost_regs.h"
+
+#define gpu_write(dev, reg, data) writel(data, dev->iomem + reg)
+#define gpu_read(dev, reg) readl(dev->iomem + reg)
+
+static irqreturn_t panfrost_gpu_irq_handler(int irq, void *data)
+{
+	struct panfrost_device *pfdev = data;
+	u32 state = gpu_read(pfdev, GPU_INT_STAT);
+	u32 fault_status = gpu_read(pfdev, GPU_FAULT_STATUS);
+	u64 address;
+	bool done = false;
+
+	if (!state)
+		return IRQ_NONE;
+
+	if (state & GPU_IRQ_MASK_ERROR) {
+		address = (u64) gpu_read(pfdev, GPU_FAULT_ADDRESS_HI) << 32;
+		address |= gpu_read(pfdev, GPU_FAULT_ADDRESS_LO);
+
+		dev_warn(pfdev->dev, "GPU Fault 0x%08x (%s) at 0x%016llx\n",
+			 fault_status & 0xFF, panfrost_exception_name(pfdev, fault_status),
+			 address);
+
+		if (state & GPU_IRQ_MULTIPLE_FAULT)
+			dev_warn(pfdev->dev, "There were multiple GPU faults - some have not been reported\n");
+
+		gpu_write(pfdev, GPU_INT_MASK, 0);
+
+		done = true;
+	}
+
+	gpu_write(pfdev, GPU_INT_CLEAR, state);
+
+	return IRQ_HANDLED;
+}
+
+int panfrost_gpu_soft_reset(struct panfrost_device *pfdev)
+{
+	int ret;
+	u32 val;
+
+	gpu_write(pfdev, GPU_INT_MASK, 0);
+	gpu_write(pfdev, GPU_INT_CLEAR, GPU_IRQ_RESET_COMPLETED);
+	gpu_write(pfdev, GPU_CMD, GPU_CMD_SOFT_RESET);
+
+	ret = readl_relaxed_poll_timeout(pfdev->iomem + GPU_INT_RAWSTAT,
+		val, val & GPU_IRQ_RESET_COMPLETED, 100, 10000);
+
+	if (ret) {
+		dev_err(pfdev->dev, "gpu soft reset timed out\n");
+		return ret;
+	}
+
+	gpu_write(pfdev, GPU_INT_CLEAR, GPU_IRQ_MASK_ALL);
+	gpu_write(pfdev, GPU_INT_MASK, GPU_IRQ_MASK_ALL);
+
+	return 0;
+}
+
+static void panfrost_gpu_init_quirks(struct panfrost_device *pfdev)
+{
+	u32 quirks = 0;
+
+	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_8443) ||
+	    panfrost_has_hw_issue(pfdev, HW_ISSUE_11035))
+		quirks |= SC_LS_PAUSEBUFFER_DISABLE;
+
+	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_10327))
+		quirks |= SC_SDC_DISABLE_OQ_DISCARD;
+
+	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_10797))
+		quirks |= SC_ENABLE_TEXGRD_FLAGS;
+
+	if (!panfrost_has_hw_issue(pfdev, GPUCORE_1619)) {
+		if (panfrost_model_cmp(pfdev, 0x750) < 0) /* T60x, T62x, T72x */
+			quirks |= SC_LS_ATTR_CHECK_DISABLE;
+		else if (panfrost_model_cmp(pfdev, 0x880) <= 0) /* T76x, T8xx */
+			quirks |= SC_LS_ALLOW_ATTR_TYPES;
+	}
+
+	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_TLS_HASHING))
+		quirks |= SC_TLS_HASH_ENABLE;
+
+	if (quirks)
+		gpu_write(pfdev, GPU_SHADER_CONFIG, quirks);
+
+
+	quirks = gpu_read(pfdev, GPU_TILER_CONFIG);
+
+	/* Set tiler clock gate override if required */
+	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_T76X_3953))
+		quirks |= TC_CLOCK_GATE_OVERRIDE;
+
+	gpu_write(pfdev, GPU_TILER_CONFIG, quirks);
+
+
+	quirks = gpu_read(pfdev, GPU_L2_MMU_CONFIG);
+
+	/* Limit read & write ID width for AXI */
+	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG))
+		quirks &= ~(L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_READS |
+			    L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_WRITES);
+	else
+		quirks &= ~(L2_MMU_CONFIG_LIMIT_EXTERNAL_READS |
+			    L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES);
+
+#if 0
+	if (kbdev->system_coherency == COHERENCY_ACE) {
+		/* Allow memory configuration disparity to be ignored, we
+		 * optimize the use of shared memory and thus we expect
+		 * some disparity in the memory configuration */
+		quirks |= L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY;
+	}
+#endif
+	gpu_write(pfdev, GPU_L2_MMU_CONFIG, quirks);
+
+	quirks = 0;
+	if ((panfrost_model_eq(pfdev, 0x860) || panfrost_model_eq(pfdev, 0x880)) &&
+	    pfdev->features.revision >= 0x2000)
+		quirks |= JM_MAX_JOB_THROTTLE_LIMIT << JM_JOB_THROTTLE_LIMIT_SHIFT;
+	else if (panfrost_model_eq(pfdev, 0x6000) &&
+		 pfdev->features.coherency_features == COHERENCY_ACE)
+		quirks |= (COHERENCY_ACE_LITE | COHERENCY_ACE) <<
+			   JM_FORCE_COHERENCY_FEATURES_SHIFT;
+
+	if (quirks)
+		gpu_write(pfdev, GPU_JM_CONFIG, quirks);
+}
+
+#define MAX_HW_REVS 6
+
+struct panfrost_model {
+	const char *name;
+	u32 id;
+	u32 id_mask;
+	u64 features;
+	u64 issues;
+	struct {
+		u32 revision;
+		u64 issues;
+	} revs[MAX_HW_REVS];
+};
+
+#define GPU_MODEL(_name, _id, ...) \
+{\
+	.name = __stringify(_name),				\
+	.id = _id,						\
+	.features = hw_features_##_name,			\
+	.issues = hw_issues_##_name,				\
+	.revs = { __VA_ARGS__ },				\
+}
+
+#define GPU_REV_EXT(name, _rev, _p, _s, stat) \
+{\
+	.revision = (_rev) << 12 | (_p) << 4 | (_s),		\
+	.issues = hw_issues_##name##_r##_rev##p##_p##stat,	\
+}
+#define GPU_REV(name, r, p) GPU_REV_EXT(name, r, p, 0, )
+
+static const struct panfrost_model gpu_models[] = {
+	/* T60x has an oddball version */
+	GPU_MODEL(t600, 0x600,
+		GPU_REV_EXT(t600, 0, 0, 1, _15dev0)),
+	GPU_MODEL(t620, 0x620,
+		GPU_REV(t620, 0, 1), GPU_REV(t620, 1, 0)),
+	GPU_MODEL(t720, 0x720),
+	GPU_MODEL(t760, 0x750,
+		GPU_REV(t760, 0, 0), GPU_REV(t760, 0, 1),
+		GPU_REV_EXT(t760, 0, 1, 0, _50rel0),
+		GPU_REV(t760, 0, 2), GPU_REV(t760, 0, 3)),
+	GPU_MODEL(t820, 0x820),
+	GPU_MODEL(t830, 0x830),
+	GPU_MODEL(t860, 0x860),
+	GPU_MODEL(t880, 0x880),
+
+	GPU_MODEL(g71, 0x6000,
+		GPU_REV_EXT(g71, 0, 0, 1, _05dev0)),
+	GPU_MODEL(g72, 0x6001),
+	GPU_MODEL(g51, 0x7000),
+	GPU_MODEL(g76, 0x7001),
+	GPU_MODEL(g52, 0x7002),
+	GPU_MODEL(g31, 0x7003,
+		GPU_REV(g31, 1, 0)),
+};
+
+static void panfrost_gpu_init_features(struct panfrost_device *pfdev)
+{
+	u32 gpu_id, num_js, major, minor, status, rev;
+	const char *name = "unknown";
+	u64 hw_feat = 0;
+	u64 hw_issues = hw_issues_all;
+	const struct panfrost_model *model;
+	int i;
+
+	pfdev->features.l2_features = gpu_read(pfdev, GPU_L2_FEATURES);
+	pfdev->features.core_features = gpu_read(pfdev, GPU_CORE_FEATURES);
+	pfdev->features.tiler_features = gpu_read(pfdev, GPU_TILER_FEATURES);
+	pfdev->features.mem_features = gpu_read(pfdev, GPU_MEM_FEATURES);
+	pfdev->features.mmu_features = gpu_read(pfdev, GPU_MMU_FEATURES);
+	pfdev->features.thread_features = gpu_read(pfdev, GPU_THREAD_FEATURES);
+	pfdev->features.coherency_features = gpu_read(pfdev, GPU_COHERENCY_FEATURES);
+	for (i = 0; i < 4; i++)
+		pfdev->features.texture_features[i] = gpu_read(pfdev, GPU_TEXTURE_FEATURES(i));
+
+	pfdev->features.as_present = gpu_read(pfdev, GPU_AS_PRESENT);
+
+	pfdev->features.js_present = gpu_read(pfdev, GPU_JS_PRESENT);
+	num_js = hweight32(pfdev->features.js_present);
+	for (i = 0; i < num_js; i++)
+		pfdev->features.js_features[i] = gpu_read(pfdev, GPU_JS_FEATURES(i));
+
+	pfdev->features.shader_present = gpu_read(pfdev, GPU_SHADER_PRESENT_LO);
+	pfdev->features.shader_present |= (u64)gpu_read(pfdev, GPU_SHADER_PRESENT_HI) << 32;
+
+	pfdev->features.tiler_present = gpu_read(pfdev, GPU_TILER_PRESENT_LO);
+	pfdev->features.tiler_present |= (u64)gpu_read(pfdev, GPU_TILER_PRESENT_HI) << 32;
+
+	pfdev->features.l2_present = gpu_read(pfdev, GPU_L2_PRESENT_LO);
+	pfdev->features.l2_present |= (u64)gpu_read(pfdev, GPU_L2_PRESENT_HI) << 32;
+	pfdev->features.nr_core_groups = hweight64(pfdev->features.l2_present);
+
+	pfdev->features.stack_present = gpu_read(pfdev, GPU_STACK_PRESENT_LO);
+	pfdev->features.stack_present |= (u64)gpu_read(pfdev, GPU_STACK_PRESENT_HI) << 32;
+
+	gpu_id = gpu_read(pfdev, GPU_ID);
+	pfdev->features.revision = gpu_id & 0xffff;
+	pfdev->features.id = gpu_id >> 16;
+
+	/* The T60x has an oddball ID value. Fix it up to the standard Midgard
+	 * format so we (and userspace) don't have to special case it.
+	 */
+	if (pfdev->features.id == 0x6956)
+		pfdev->features.id = 0x0600;
+
+	major = (pfdev->features.revision >> 12) & 0xf;
+	minor = (pfdev->features.revision >> 4) & 0xff;
+	status = pfdev->features.revision & 0xf;
+	rev = pfdev->features.revision;
+
+	gpu_id = pfdev->features.id;
+
+	for (model = gpu_models; model->name; model++) {
+		int best = -1;
+
+		if (!panfrost_model_eq(pfdev, model->id))
+			continue;
+
+		name = model->name;
+		hw_feat = model->features;
+		hw_issues |= model->issues;
+		for (i = 0; i < MAX_HW_REVS; i++) {
+			if (model->revs[i].revision == rev) {
+				best = i;
+				break;
+			} else if (model->revs[i].revision == (rev & ~0xf))
+				best = i;
+		}
+
+		if (best >= 0)
+			hw_issues |= model->revs[best].issues;
+
+		break;
+	}
+
+	bitmap_from_u64(pfdev->features.hw_features, hw_feat);
+	bitmap_from_u64(pfdev->features.hw_issues, hw_issues);
+
+	dev_info(pfdev->dev, "mali-%s id 0x%x major 0x%x minor 0x%x status 0x%x",
+		 name, gpu_id, major, minor, status);
+	dev_info(pfdev->dev, "features: %64pb, issues: %64pb",
+		 pfdev->features.hw_features,
+		 pfdev->features.hw_issues);
+
+	dev_info(pfdev->dev, "Features: L2:0x%08x Shader:0x%08x Tiler:0x%08x Mem:0x%0x MMU:0x%08x AS:0x%x JS:0x%x",
+		 gpu_read(pfdev, GPU_L2_FEATURES),
+		 gpu_read(pfdev, GPU_CORE_FEATURES),
+		 gpu_read(pfdev, GPU_TILER_FEATURES),
+		 gpu_read(pfdev, GPU_MEM_FEATURES),
+		 gpu_read(pfdev, GPU_MMU_FEATURES),
+		 gpu_read(pfdev, GPU_AS_PRESENT),
+		 gpu_read(pfdev, GPU_JS_PRESENT));
+
+	dev_info(pfdev->dev, "shader_present=0x%0llx l2_present=0x%0llx",
+		 pfdev->features.shader_present, pfdev->features.l2_present);
+}
+
+void panfrost_gpu_power_on(struct panfrost_device *pfdev)
+{
+	int ret;
+	u32 val;
+
+	/* Just turn on everything for now */
+	gpu_write(pfdev, SHADER_PWRON_LO, pfdev->features.shader_present);
+	ret = readl_relaxed_poll_timeout(pfdev->iomem + SHADER_READY_LO,
+		val, val == pfdev->features.shader_present, 100, 1000);
+
+	gpu_write(pfdev, TILER_PWRON_LO, pfdev->features.tiler_present);
+	ret |= readl_relaxed_poll_timeout(pfdev->iomem + TILER_READY_LO,
+		val, val == pfdev->features.tiler_present, 100, 1000);
+
+	gpu_write(pfdev, L2_PWRON_LO, pfdev->features.l2_present);
+	ret |= readl_relaxed_poll_timeout(pfdev->iomem + L2_READY_LO,
+		val, val == pfdev->features.l2_present, 100, 1000);
+
+	gpu_write(pfdev, STACK_PWRON_LO, pfdev->features.stack_present);
+	ret |= readl_relaxed_poll_timeout(pfdev->iomem + STACK_READY_LO,
+		val, val == pfdev->features.stack_present, 100, 1000);
+
+	if (ret)
+		dev_err(pfdev->dev, "error powering up gpu");
+}
+
+void panfrost_gpu_power_off(struct panfrost_device *pfdev)
+{
+	gpu_write(pfdev, SHADER_PWROFF_LO, 0);
+	gpu_write(pfdev, TILER_PWROFF_LO, 0);
+	gpu_write(pfdev, L2_PWROFF_LO, 0);
+	gpu_write(pfdev, STACK_PWROFF_LO, 0);
+}
+
+int panfrost_gpu_init(struct panfrost_device *pfdev)
+{
+	int err, irq;
+
+	err = panfrost_gpu_soft_reset(pfdev);
+	if (err)
+		return err;
+
+	panfrost_gpu_init_features(pfdev);
+
+	irq = platform_get_irq_byname(to_platform_device(pfdev->dev), "gpu");
+	if (irq <= 0)
+		return -ENODEV;
+
+	err = devm_request_irq(pfdev->dev, irq, panfrost_gpu_irq_handler,
+			       IRQF_SHARED, "gpu", pfdev);
+	if (err) {
+		dev_err(pfdev->dev, "failed to request gpu irq");
+		return err;
+	}
+
+	panfrost_gpu_init_quirks(pfdev);
+	panfrost_gpu_power_on(pfdev);
+
+	return 0;
+}
+
+void panfrost_gpu_fini(struct panfrost_device *pfdev)
+{
+	panfrost_gpu_power_off(pfdev);
+}
+
+u32 panfrost_gpu_get_latest_flush_id(struct panfrost_device *pfdev)
+{
+	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_FLUSH_REDUCTION))
+		return gpu_read(pfdev, GPU_LATEST_FLUSH_ID);
+	return 0;
+}
diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.h b/drivers/gpu/drm/panfrost/panfrost_gpu.h
new file mode 100644
index 000000000000..4112412087b2
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_gpu.h
@@ -0,0 +1,19 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
+/* Copyright 2019 Collabora ltd. */
+
+#ifndef __PANFROST_GPU_H__
+#define __PANFROST_GPU_H__
+
+struct panfrost_device;
+
+int panfrost_gpu_init(struct panfrost_device *pfdev);
+void panfrost_gpu_fini(struct panfrost_device *pfdev);
+
+u32 panfrost_gpu_get_latest_flush_id(struct panfrost_device *pfdev);
+
+int panfrost_gpu_soft_reset(struct panfrost_device *pfdev);
+void panfrost_gpu_power_on(struct panfrost_device *pfdev);
+void panfrost_gpu_power_off(struct panfrost_device *pfdev);
+
+#endif
diff --git a/drivers/gpu/drm/panfrost/panfrost_issues.h b/drivers/gpu/drm/panfrost/panfrost_issues.h
new file mode 100644
index 000000000000..cec6dcdadb5c
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_issues.h
@@ -0,0 +1,176 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* (C) COPYRIGHT 2014-2018 ARM Limited. All rights reserved. */
+/* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
+#ifndef __PANFROST_ISSUES_H__
+#define __PANFROST_ISSUES_H__
+
+#include <linux/bitops.h>
+
+#include "panfrost_device.h"
+
+/*
+ * This is not a complete list of issues, but only the ones the driver needs
+ * to care about.
+ */
+enum panfrost_hw_issue {
+	HW_ISSUE_6367,
+	HW_ISSUE_6787,
+	HW_ISSUE_8186,
+	HW_ISSUE_8245,
+	HW_ISSUE_8316,
+	HW_ISSUE_8394,
+	HW_ISSUE_8401,
+	HW_ISSUE_8408,
+	HW_ISSUE_8443,
+	HW_ISSUE_8987,
+	HW_ISSUE_9435,
+	HW_ISSUE_9510,
+	HW_ISSUE_9630,
+	HW_ISSUE_10327,
+	HW_ISSUE_10649,
+	HW_ISSUE_10676,
+	HW_ISSUE_10797,
+	HW_ISSUE_10817,
+	HW_ISSUE_10883,
+	HW_ISSUE_10959,
+	HW_ISSUE_10969,
+	HW_ISSUE_11020,
+	HW_ISSUE_11024,
+	HW_ISSUE_11035,
+	HW_ISSUE_11056,
+	HW_ISSUE_T76X_3542,
+	HW_ISSUE_T76X_3953,
+	HW_ISSUE_TMIX_8463,
+	GPUCORE_1619,
+	HW_ISSUE_TMIX_8438,
+	HW_ISSUE_TGOX_R1_1234,
+	HW_ISSUE_END
+};
+
+#define hw_issues_all (\
+	BIT_ULL(HW_ISSUE_9435))
+
+#define hw_issues_t600 (\
+	BIT_ULL(HW_ISSUE_6367) | \
+	BIT_ULL(HW_ISSUE_6787) | \
+	BIT_ULL(HW_ISSUE_8408) | \
+	BIT_ULL(HW_ISSUE_9510) | \
+	BIT_ULL(HW_ISSUE_10649) | \
+	BIT_ULL(HW_ISSUE_10676) | \
+	BIT_ULL(HW_ISSUE_10883) | \
+	BIT_ULL(HW_ISSUE_11020) | \
+	BIT_ULL(HW_ISSUE_11035) | \
+	BIT_ULL(HW_ISSUE_11056) | \
+	BIT_ULL(HW_ISSUE_TMIX_8438))
+
+#define hw_issues_t600_r0p0_15dev0 (\
+	BIT_ULL(HW_ISSUE_8186) | \
+	BIT_ULL(HW_ISSUE_8245) | \
+	BIT_ULL(HW_ISSUE_8316) | \
+	BIT_ULL(HW_ISSUE_8394) | \
+	BIT_ULL(HW_ISSUE_8401) | \
+	BIT_ULL(HW_ISSUE_8443) | \
+	BIT_ULL(HW_ISSUE_8987) | \
+	BIT_ULL(HW_ISSUE_9630) | \
+	BIT_ULL(HW_ISSUE_10969) | \
+	BIT_ULL(GPUCORE_1619))
+
+#define hw_issues_t620 (\
+	BIT_ULL(HW_ISSUE_10649) | \
+	BIT_ULL(HW_ISSUE_10883) | \
+	BIT_ULL(HW_ISSUE_10959) | \
+	BIT_ULL(HW_ISSUE_11056) | \
+	BIT_ULL(HW_ISSUE_TMIX_8438))
+
+#define hw_issues_t620_r0p1 (\
+	BIT_ULL(HW_ISSUE_10327) | \
+	BIT_ULL(HW_ISSUE_10676) | \
+	BIT_ULL(HW_ISSUE_10817) | \
+	BIT_ULL(HW_ISSUE_11020) | \
+	BIT_ULL(HW_ISSUE_11024) | \
+	BIT_ULL(HW_ISSUE_11035))
+
+#define hw_issues_t620_r1p0 (\
+	BIT_ULL(HW_ISSUE_11020) | \
+	BIT_ULL(HW_ISSUE_11024))
+
+#define hw_issues_t720 (\
+	BIT_ULL(HW_ISSUE_10649) | \
+	BIT_ULL(HW_ISSUE_10797) | \
+	BIT_ULL(HW_ISSUE_10883) | \
+	BIT_ULL(HW_ISSUE_11056) | \
+	BIT_ULL(HW_ISSUE_TMIX_8438))
+
+#define hw_issues_t760 (\
+	BIT_ULL(HW_ISSUE_10883) | \
+	BIT_ULL(HW_ISSUE_T76X_3953) | \
+	BIT_ULL(HW_ISSUE_TMIX_8438))
+
+#define hw_issues_t760_r0p0 (\
+	BIT_ULL(HW_ISSUE_11020) | \
+	BIT_ULL(HW_ISSUE_11024) | \
+	BIT_ULL(HW_ISSUE_T76X_3542))
+
+#define hw_issues_t760_r0p1 (\
+	BIT_ULL(HW_ISSUE_11020) | \
+	BIT_ULL(HW_ISSUE_11024) | \
+	BIT_ULL(HW_ISSUE_T76X_3542))
+
+#define hw_issues_t760_r0p1_50rel0 (\
+	BIT_ULL(HW_ISSUE_T76X_3542))
+
+#define hw_issues_t760_r0p2 (\
+	BIT_ULL(HW_ISSUE_11020) | \
+	BIT_ULL(HW_ISSUE_11024) | \
+	BIT_ULL(HW_ISSUE_T76X_3542))
+
+#define hw_issues_t760_r0p3 (\
+	BIT_ULL(HW_ISSUE_T76X_3542))
+
+#define hw_issues_t820 (\
+	BIT_ULL(HW_ISSUE_10883) | \
+	BIT_ULL(HW_ISSUE_T76X_3953) | \
+	BIT_ULL(HW_ISSUE_TMIX_8438))
+
+#define hw_issues_t830 (\
+	BIT_ULL(HW_ISSUE_10883) | \
+	BIT_ULL(HW_ISSUE_T76X_3953) | \
+	BIT_ULL(HW_ISSUE_TMIX_8438))
+
+#define hw_issues_t860 (\
+	BIT_ULL(HW_ISSUE_10883) | \
+	BIT_ULL(HW_ISSUE_T76X_3953) | \
+	BIT_ULL(HW_ISSUE_TMIX_8438))
+
+#define hw_issues_t880 (\
+	BIT_ULL(HW_ISSUE_10883) | \
+	BIT_ULL(HW_ISSUE_T76X_3953) | \
+	BIT_ULL(HW_ISSUE_TMIX_8438))
+
+#define hw_issues_g31 0
+
+#define hw_issues_g31_r1p0 (\
+	BIT_ULL(HW_ISSUE_TGOX_R1_1234))
+
+#define hw_issues_g51 0
+
+#define hw_issues_g52 0
+
+#define hw_issues_g71 (\
+	BIT_ULL(HW_ISSUE_TMIX_8463) | \
+	BIT_ULL(HW_ISSUE_TMIX_8438))
+
+#define hw_issues_g71_r0p0_05dev0 (\
+	BIT_ULL(HW_ISSUE_T76X_3953))
+
+#define hw_issues_g72 0
+
+#define hw_issues_g76 0
+
+static inline bool panfrost_has_hw_issue(struct panfrost_device *pfdev,
+					 enum panfrost_hw_issue issue)
+{
+	return test_bit(issue, pfdev->features.hw_issues);
+}
+
+#endif /* __PANFROST_ISSUES_H__ */
diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
new file mode 100644
index 000000000000..482e86866b2c
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_job.c
@@ -0,0 +1,556 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+/* Copyright 2019 Collabora ltd. */
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/reservation.h>
+#include <drm/gpu_scheduler.h>
+#include <drm/panfrost_drm.h>
+
+#include "panfrost_device.h"
+#include "panfrost_devfreq.h"
+#include "panfrost_job.h"
+#include "panfrost_features.h"
+#include "panfrost_issues.h"
+#include "panfrost_gem.h"
+#include "panfrost_regs.h"
+#include "panfrost_gpu.h"
+#include "panfrost_mmu.h"
+
+#define job_write(dev, reg, data) writel(data, dev->iomem + (reg))
+#define job_read(dev, reg) readl(dev->iomem + (reg))
+
+struct panfrost_queue_state {
+	struct drm_gpu_scheduler sched;
+
+	u64 fence_context;
+	u64 emit_seqno;
+};
+
+struct panfrost_job_slot {
+	struct panfrost_queue_state queue[NUM_JOB_SLOTS];
+	spinlock_t job_lock;
+};
+
+static struct panfrost_job *
+to_panfrost_job(struct drm_sched_job *sched_job)
+{
+	return container_of(sched_job, struct panfrost_job, base);
+}
+
+struct panfrost_fence {
+	struct dma_fence base;
+	struct drm_device *dev;
+	/* panfrost seqno for signaled() test */
+	u64 seqno;
+	int queue;
+};
+
+static inline struct panfrost_fence *
+to_panfrost_fence(struct dma_fence *fence)
+{
+	return (struct panfrost_fence *)fence;
+}
+
+static const char *panfrost_fence_get_driver_name(struct dma_fence *fence)
+{
+	return "panfrost";
+}
+
+static const char *panfrost_fence_get_timeline_name(struct dma_fence *fence)
+{
+	struct panfrost_fence *f = to_panfrost_fence(fence);
+
+	switch (f->queue) {
+	case 0:
+		return "panfrost-js-0";
+	case 1:
+		return "panfrost-js-1";
+	case 2:
+		return "panfrost-js-2";
+	default:
+		return NULL;
+	}
+}
+
+static const struct dma_fence_ops panfrost_fence_ops = {
+	.get_driver_name = panfrost_fence_get_driver_name,
+	.get_timeline_name = panfrost_fence_get_timeline_name,
+};
+
+static struct dma_fence *panfrost_fence_create(struct panfrost_device *pfdev, int js_num)
+{
+	struct panfrost_fence *fence;
+	struct panfrost_job_slot *js = pfdev->js;
+
+	fence = kzalloc(sizeof(*fence), GFP_KERNEL);
+	if (!fence)
+		return ERR_PTR(-ENOMEM);
+
+	fence->dev = pfdev->ddev;
+	fence->queue = js_num;
+	fence->seqno = ++js->queue[js_num].emit_seqno;
+	dma_fence_init(&fence->base, &panfrost_fence_ops, &js->job_lock,
+		       js->queue[js_num].fence_context, fence->seqno);
+
+	return &fence->base;
+}
+
+static int panfrost_job_get_slot(struct panfrost_job *job)
+{
+	/* JS0: fragment jobs.
+	 * JS1: vertex/tiler jobs
+	 * JS2: compute jobs
+	 */
+	if (job->requirements & PANFROST_JD_REQ_FS)
+		return 0;
+
+/* Not exposed to userspace yet */
+#if 0
+	if (job->requirements & PANFROST_JD_REQ_ONLY_COMPUTE) {
+		if ((job->requirements & PANFROST_JD_REQ_CORE_GRP_MASK) &&
+		    (job->pfdev->features.nr_core_groups == 2))
+			return 2;
+		if (panfrost_has_hw_issue(job->pfdev, HW_ISSUE_8987))
+			return 2;
+	}
+#endif
+	return 1;
+}
+
+static void panfrost_job_write_affinity(struct panfrost_device *pfdev,
+					u32 requirements,
+					int js)
+{
+	u64 affinity;
+
+	/*
+	 * Use all cores for now.
+	 * Eventually we may need to support tiler only jobs and h/w with
+	 * multiple (2) coherent core groups
+	 */
+	affinity = pfdev->features.shader_present;
+
+	job_write(pfdev, JS_AFFINITY_NEXT_LO(js), affinity & 0xFFFFFFFF);
+	job_write(pfdev, JS_AFFINITY_NEXT_HI(js), affinity >> 32);
+}
+
+static void panfrost_job_hw_submit(struct panfrost_job *job, int js)
+{
+	struct panfrost_device *pfdev = job->pfdev;
+	unsigned long flags;
+	u32 cfg;
+	u64 jc_head = job->jc;
+	int ret;
+
+	panfrost_devfreq_update_utilization(pfdev, js, false);
+
+	ret = pm_runtime_get_sync(pfdev->dev);
+	if (ret < 0)
+		return;
+
+	if (WARN_ON(job_read(pfdev, JS_COMMAND_NEXT(js))))
+		goto end;
+
+	spin_lock_irqsave(&pfdev->hwaccess_lock, flags);
+
+	job_write(pfdev, JS_HEAD_NEXT_LO(js), jc_head & 0xFFFFFFFF);
+	job_write(pfdev, JS_HEAD_NEXT_HI(js), jc_head >> 32);
+
+	panfrost_job_write_affinity(pfdev, job->requirements, js);
+
+	/* start MMU, medium priority, cache clean/flush on end, clean/flush on
+	 * start */
+	// TODO: different address spaces
+	cfg = JS_CONFIG_THREAD_PRI(8) |
+		JS_CONFIG_START_FLUSH_CLEAN_INVALIDATE |
+		JS_CONFIG_END_FLUSH_CLEAN_INVALIDATE;
+
+	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_FLUSH_REDUCTION))
+		cfg |= JS_CONFIG_ENABLE_FLUSH_REDUCTION;
+
+	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_10649))
+		cfg |= JS_CONFIG_START_MMU;
+
+	job_write(pfdev, JS_CONFIG_NEXT(js), cfg);
+
+	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_FLUSH_REDUCTION))
+		job_write(pfdev, JS_FLUSH_ID_NEXT(js), job->flush_id);
+
+	/* GO ! */
+	dev_dbg(pfdev->dev, "JS: Submitting atom %p to js[%d] with head=0x%llx",
+				job, js, jc_head);
+
+	job_write(pfdev, JS_COMMAND_NEXT(js), JS_COMMAND_START);
+
+	spin_unlock_irqrestore(&pfdev->hwaccess_lock, flags);
+
+end:
+	pm_runtime_mark_last_busy(pfdev->dev);
+	pm_runtime_put_autosuspend(pfdev->dev);
+}
+
+static void panfrost_acquire_object_fences(struct drm_gem_object **bos,
+					   int bo_count,
+					   struct dma_fence **implicit_fences)
+{
+	int i;
+
+	for (i = 0; i < bo_count; i++)
+		implicit_fences[i] = reservation_object_get_excl_rcu(bos[i]->resv);
+}
+
+static void panfrost_attach_object_fences(struct drm_gem_object **bos,
+					  int bo_count,
+					  struct dma_fence *fence)
+{
+	int i;
+
+	for (i = 0; i < bo_count; i++)
+		reservation_object_add_excl_fence(bos[i]->resv, fence);
+}
+
+int panfrost_job_push(struct panfrost_job *job)
+{
+	struct panfrost_device *pfdev = job->pfdev;
+	int slot = panfrost_job_get_slot(job);
+	struct drm_sched_entity *entity = &job->file_priv->sched_entity[slot];
+	struct ww_acquire_ctx acquire_ctx;
+	int ret = 0;
+
+	mutex_lock(&pfdev->sched_lock);
+
+	ret = drm_gem_lock_reservations(job->bos, job->bo_count,
+					    &acquire_ctx);
+	if (ret) {
+		mutex_unlock(&pfdev->sched_lock);
+		return ret;
+	}
+
+	ret = drm_sched_job_init(&job->base, entity, NULL);
+	if (ret) {
+		mutex_unlock(&pfdev->sched_lock);
+		goto unlock;
+	}
+
+	job->render_done_fence = dma_fence_get(&job->base.s_fence->finished);
+
+	kref_get(&job->refcount); /* put by scheduler job completion */
+
+	drm_sched_entity_push_job(&job->base, entity);
+
+	mutex_unlock(&pfdev->sched_lock);
+
+	panfrost_acquire_object_fences(job->bos, job->bo_count,
+				       job->implicit_fences);
+
+	panfrost_attach_object_fences(job->bos, job->bo_count,
+				      job->render_done_fence);
+
+unlock:
+	drm_gem_unlock_reservations(job->bos, job->bo_count, &acquire_ctx);
+
+	return ret;
+}
+
+static void panfrost_job_cleanup(struct kref *ref)
+{
+	struct panfrost_job *job = container_of(ref, struct panfrost_job,
+						refcount);
+	unsigned int i;
+
+	for (i = 0; i < job->in_fence_count; i++)
+		dma_fence_put(job->in_fences[i]);
+	kvfree(job->in_fences);
+
+	for (i = 0; i < job->bo_count; i++)
+		dma_fence_put(job->implicit_fences[i]);
+	kvfree(job->implicit_fences);
+
+	dma_fence_put(job->done_fence);
+	dma_fence_put(job->render_done_fence);
+
+	for (i = 0; i < job->bo_count; i++)
+		drm_gem_object_put_unlocked(job->bos[i]);
+	kvfree(job->bos);
+
+	kfree(job);
+}
+
+void panfrost_job_put(struct panfrost_job *job)
+{
+	kref_put(&job->refcount, panfrost_job_cleanup);
+}
+
+static void panfrost_job_free(struct drm_sched_job *sched_job)
+{
+	struct panfrost_job *job = to_panfrost_job(sched_job);
+
+	drm_sched_job_cleanup(sched_job);
+
+	panfrost_job_put(job);
+}
+
+static struct dma_fence *panfrost_job_dependency(struct drm_sched_job *sched_job,
+						 struct drm_sched_entity *s_entity)
+{
+	struct panfrost_job *job = to_panfrost_job(sched_job);
+	struct dma_fence *fence;
+	unsigned int i;
+
+	/* Explicit fences */
+	for (i = 0; i < job->in_fence_count; i++) {
+		if (job->in_fences[i]) {
+			fence = job->in_fences[i];
+			job->in_fences[i] = NULL;
+			return fence;
+		}
+	}
+
+	/* Implicit fences, max. one per BO */
+	for (i = 0; i < job->bo_count; i++) {
+		if (job->implicit_fences[i]) {
+			fence = job->implicit_fences[i];
+			job->implicit_fences[i] = NULL;
+			return fence;
+		}
+	}
+
+	return NULL;
+}
+
+static struct dma_fence *panfrost_job_run(struct drm_sched_job *sched_job)
+{
+	struct panfrost_job *job = to_panfrost_job(sched_job);
+	struct panfrost_device *pfdev = job->pfdev;
+	int slot = panfrost_job_get_slot(job);
+	struct dma_fence *fence = NULL;
+
+	if (unlikely(job->base.s_fence->finished.error))
+		return NULL;
+
+	pfdev->jobs[slot] = job;
+
+	fence = panfrost_fence_create(pfdev, slot);
+	if (IS_ERR(fence))
+		return NULL;
+
+	if (job->done_fence)
+		dma_fence_put(job->done_fence);
+	job->done_fence = dma_fence_get(fence);
+
+	panfrost_job_hw_submit(job, slot);
+
+	return fence;
+}
+
+void panfrost_job_enable_interrupts(struct panfrost_device *pfdev)
+{
+	int j;
+	u32 irq_mask = 0;
+
+	for (j = 0; j < NUM_JOB_SLOTS; j++) {
+		irq_mask |= MK_JS_MASK(j);
+	}
+
+	job_write(pfdev, JOB_INT_CLEAR, irq_mask);
+	job_write(pfdev, JOB_INT_MASK, irq_mask);
+}
+
+static void panfrost_job_timedout(struct drm_sched_job *sched_job)
+{
+	struct panfrost_job *job = to_panfrost_job(sched_job);
+	struct panfrost_device *pfdev = job->pfdev;
+	int js = panfrost_job_get_slot(job);
+	int i;
+
+	/*
+	 * If the GPU managed to complete this jobs fence, the timeout is
+	 * spurious. Bail out.
+	 */
+	if (dma_fence_is_signaled(job->done_fence))
+		return;
+
+	dev_err(pfdev->dev, "gpu sched timeout, js=%d, status=0x%x, head=0x%x, tail=0x%x, sched_job=%p",
+		js,
+		job_read(pfdev, JS_STATUS(js)),
+		job_read(pfdev, JS_HEAD_LO(js)),
+		job_read(pfdev, JS_TAIL_LO(js)),
+		sched_job);
+
+	for (i = 0; i < NUM_JOB_SLOTS; i++)
+		drm_sched_stop(&pfdev->js->queue[i].sched);
+
+	if(sched_job)
+		drm_sched_increase_karma(sched_job);
+
+	//panfrost_core_dump(pfdev);
+
+	panfrost_devfreq_update_utilization(pfdev, js, true);
+	panfrost_gpu_soft_reset(pfdev);
+
+	/* TODO: Re-enable all other address spaces */
+	panfrost_mmu_enable(pfdev, 0);
+	panfrost_gpu_power_on(pfdev);
+	panfrost_job_enable_interrupts(pfdev);
+
+	for (i = 0; i < NUM_JOB_SLOTS; i++)
+		drm_sched_resubmit_jobs(&pfdev->js->queue[i].sched);
+
+	/* restart scheduler after GPU is usable again */
+	for (i = 0; i < NUM_JOB_SLOTS; i++)
+		drm_sched_start(&pfdev->js->queue[i].sched, true);
+}
+
+static const struct drm_sched_backend_ops panfrost_sched_ops = {
+	.dependency = panfrost_job_dependency,
+	.run_job = panfrost_job_run,
+	.timedout_job = panfrost_job_timedout,
+	.free_job = panfrost_job_free
+};
+
+static irqreturn_t panfrost_job_irq_handler(int irq, void *data)
+{
+	struct panfrost_device *pfdev = data;
+	u32 status = job_read(pfdev, JOB_INT_STAT);
+	int j;
+
+	dev_dbg(pfdev->dev, "jobslot irq status=%x\n", status);
+
+	if (!status)
+		return IRQ_NONE;
+
+	pm_runtime_mark_last_busy(pfdev->dev);
+
+	for (j = 0; status; j++) {
+		u32 mask = MK_JS_MASK(j);
+
+		if (!(status & mask))
+			continue;
+
+		job_write(pfdev, JOB_INT_CLEAR, mask);
+
+		if (status & JOB_INT_MASK_ERR(j)) {
+			job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_NOP);
+			job_write(pfdev, JS_COMMAND(j), JS_COMMAND_HARD_STOP_0);
+
+			dev_err(pfdev->dev, "js fault, js=%d, status=%s, head=0x%x, tail=0x%x",
+				j,
+				panfrost_exception_name(pfdev, job_read(pfdev, JS_STATUS(j))),
+				job_read(pfdev, JS_HEAD_LO(j)),
+				job_read(pfdev, JS_TAIL_LO(j)));
+		}
+
+		if (status & JOB_INT_MASK_DONE(j)) {
+			panfrost_devfreq_update_utilization(pfdev, j, true);
+			dma_fence_signal(pfdev->jobs[j]->done_fence);
+		}
+
+		status &= ~mask;
+	}
+
+	return IRQ_HANDLED;
+}
+
+int panfrost_job_init(struct panfrost_device *pfdev)
+{
+	struct panfrost_job_slot *js;
+	int ret, j, irq;
+
+	pfdev->js = js = devm_kzalloc(pfdev->dev, sizeof(*js), GFP_KERNEL);
+	if (!js)
+		return -ENOMEM;
+
+	spin_lock_init(&js->job_lock);
+
+	irq = platform_get_irq_byname(to_platform_device(pfdev->dev), "job");
+	if (irq <= 0)
+		return -ENODEV;
+
+	ret = devm_request_irq(pfdev->dev, irq, panfrost_job_irq_handler,
+			       IRQF_SHARED, "job", pfdev);
+	if (ret) {
+		dev_err(pfdev->dev, "failed to request job irq");
+		return ret;
+	}
+
+	for (j = 0; j < NUM_JOB_SLOTS; j++) {
+		js->queue[j].fence_context = dma_fence_context_alloc(1);
+
+		ret = drm_sched_init(&js->queue[j].sched,
+				     &panfrost_sched_ops,
+				     1, 0, msecs_to_jiffies(500),
+				     "pan_js");
+		if (ret) {
+			dev_err(pfdev->dev, "Failed to create scheduler: %d.", ret);
+			goto err_sched;
+		}
+	}
+
+	panfrost_job_enable_interrupts(pfdev);
+
+	return 0;
+
+err_sched:
+	for (j--; j >= 0; j--)
+		drm_sched_fini(&js->queue[j].sched);
+
+	return ret;
+}
+
+void panfrost_job_fini(struct panfrost_device *pfdev)
+{
+	struct panfrost_job_slot *js = pfdev->js;
+	int j;
+
+	job_write(pfdev, JOB_INT_MASK, 0);
+
+	for (j = 0; j < NUM_JOB_SLOTS; j++)
+		drm_sched_fini(&js->queue[j].sched);
+
+}
+
+int panfrost_job_open(struct panfrost_file_priv *panfrost_priv)
+{
+	struct panfrost_device *pfdev = panfrost_priv->pfdev;
+	struct panfrost_job_slot *js = pfdev->js;
+	struct drm_sched_rq *rq;
+	int ret, i;
+
+	for (i = 0; i < NUM_JOB_SLOTS; i++) {
+		rq = &js->queue[i].sched.sched_rq[DRM_SCHED_PRIORITY_NORMAL];
+		ret = drm_sched_entity_init(&panfrost_priv->sched_entity[i], &rq, 1, NULL);
+		if (WARN_ON(ret))
+			return ret;
+	}
+	return 0;
+}
+
+void panfrost_job_close(struct panfrost_file_priv *panfrost_priv)
+{
+	int i;
+
+	for (i = 0; i < NUM_JOB_SLOTS; i++)
+		drm_sched_entity_destroy(&panfrost_priv->sched_entity[i]);
+}
+
+int panfrost_job_is_idle(struct panfrost_device *pfdev)
+{
+	struct panfrost_job_slot *js = pfdev->js;
+	int i;
+
+	for (i = 0; i < NUM_JOB_SLOTS; i++) {
+		/* If there are any jobs in the HW queue, we're not idle */
+		if (atomic_read(&js->queue[i].sched.hw_rq_count))
+			return false;
+
+		/* Check whether the hardware is idle */
+		if (job_read(pfdev, JS_STATUS(i)) == JS_STATUS_EVENT_ACTIVE)
+			return false;
+	}
+
+	return true;
+}
diff --git a/drivers/gpu/drm/panfrost/panfrost_job.h b/drivers/gpu/drm/panfrost/panfrost_job.h
new file mode 100644
index 000000000000..62454128a792
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_job.h
@@ -0,0 +1,51 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright 2019 Collabora ltd. */
+
+#ifndef __PANFROST_JOB_H__
+#define __PANFROST_JOB_H__
+
+#include <uapi/drm/panfrost_drm.h>
+#include <drm/gpu_scheduler.h>
+
+struct panfrost_device;
+struct panfrost_gem_object;
+struct panfrost_file_priv;
+
+struct panfrost_job {
+	struct drm_sched_job base;
+
+	struct kref refcount;
+
+	struct panfrost_device *pfdev;
+	struct panfrost_file_priv *file_priv;
+
+	/* Optional fences userspace can pass in for the job to depend on. */
+	struct dma_fence **in_fences;
+	u32 in_fence_count;
+
+	/* Fence to be signaled by IRQ handler when the job is complete. */
+	struct dma_fence *done_fence;
+
+	__u64 jc;
+	__u32 requirements;
+	__u32 flush_id;
+
+	/* Exclusive fences we have taken from the BOs to wait for */
+	struct dma_fence **implicit_fences;
+	struct drm_gem_object **bos;
+	u32 bo_count;
+
+	/* Fence to be signaled by drm-sched once its done with the job */
+	struct dma_fence *render_done_fence;
+};
+
+int panfrost_job_init(struct panfrost_device *pfdev);
+void panfrost_job_fini(struct panfrost_device *pfdev);
+int panfrost_job_open(struct panfrost_file_priv *panfrost_priv);
+void panfrost_job_close(struct panfrost_file_priv *panfrost_priv);
+int panfrost_job_push(struct panfrost_job *job);
+void panfrost_job_put(struct panfrost_job *job);
+void panfrost_job_enable_interrupts(struct panfrost_device *pfdev);
+int panfrost_job_is_idle(struct panfrost_device *pfdev);
+
+#endif
diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
new file mode 100644
index 000000000000..744f5f359386
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
@@ -0,0 +1,366 @@ 
+// SPDX-License-Identifier:	GPL-2.0
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/io-pgtable.h>
+#include <linux/iommu.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/sizes.h>
+
+#include "panfrost_device.h"
+#include "panfrost_mmu.h"
+#include "panfrost_gem.h"
+#include "panfrost_features.h"
+#include "panfrost_regs.h"
+
+#define mmu_write(dev, reg, data) writel(data, dev->iomem + reg)
+#define mmu_read(dev, reg) readl(dev->iomem + reg)
+
+struct panfrost_mmu {
+	struct io_pgtable_cfg pgtbl_cfg;
+	struct io_pgtable_ops *pgtbl_ops;
+	struct mutex lock;
+};
+
+static int wait_ready(struct panfrost_device *pfdev, u32 as_nr)
+{
+	int ret;
+	u32 val;
+
+	/* Wait for the MMU status to indicate there is no active command, in
+	 * case one is pending. Do not log remaining register accesses. */
+	ret = readl_relaxed_poll_timeout_atomic(pfdev->iomem + AS_STATUS(as_nr),
+		val, !(val & AS_STATUS_AS_ACTIVE), 10, 1000);
+
+	if (ret)
+		dev_err(pfdev->dev, "AS_ACTIVE bit stuck\n");
+
+	return ret;
+}
+
+static int write_cmd(struct panfrost_device *pfdev, u32 as_nr, u32 cmd)
+{
+	int status;
+
+	/* write AS_COMMAND when MMU is ready to accept another command */
+	status = wait_ready(pfdev, as_nr);
+	if (!status)
+		mmu_write(pfdev, AS_COMMAND(as_nr), cmd);
+
+	return status;
+}
+
+static void lock_region(struct panfrost_device *pfdev, u32 as_nr,
+			u64 iova, size_t size)
+{
+	u8 region_width;
+	u64 region = iova & PAGE_MASK;
+	/*
+	 * fls returns (given the ASSERT above):
+	 * 1 .. 32
+	 *
+	 * 10 + fls(num_pages)
+	 * results in the range (11 .. 42)
+	 */
+
+	size = round_up(size, PAGE_SIZE);
+
+	region_width = 10 + fls(size >> PAGE_SHIFT);
+	if ((size >> PAGE_SHIFT) != (1ul << (region_width - 11))) {
+		/* not pow2, so must go up to the next pow2 */
+		region_width += 1;
+	}
+	region |= region_width;
+
+	/* Lock the region that needs to be updated */
+	mmu_write(pfdev, AS_LOCKADDR_LO(as_nr), region & 0xFFFFFFFFUL);
+	mmu_write(pfdev, AS_LOCKADDR_HI(as_nr), (region >> 32) & 0xFFFFFFFFUL);
+	write_cmd(pfdev, as_nr, AS_COMMAND_LOCK);
+}
+
+
+static int mmu_hw_do_operation(struct panfrost_device *pfdev, u32 as_nr,
+		u64 iova, size_t size, u32 op)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&pfdev->hwaccess_lock, flags);
+
+	if (op != AS_COMMAND_UNLOCK)
+		lock_region(pfdev, as_nr, iova, size);
+
+	/* Run the MMU operation */
+	write_cmd(pfdev, as_nr, op);
+
+	/* Wait for the flush to complete */
+	ret = wait_ready(pfdev, as_nr);
+
+	spin_unlock_irqrestore(&pfdev->hwaccess_lock, flags);
+
+	return ret;
+}
+
+void panfrost_mmu_enable(struct panfrost_device *pfdev, u32 as_nr)
+{
+	struct io_pgtable_cfg *cfg = &pfdev->mmu->pgtbl_cfg;
+	u64 transtab = cfg->arm_mali_lpae_cfg.transtab;
+	u64 memattr = cfg->arm_mali_lpae_cfg.memattr;
+
+	mmu_write(pfdev, MMU_INT_CLEAR, ~0);
+	mmu_write(pfdev, MMU_INT_MASK, ~0);
+
+	mmu_write(pfdev, AS_TRANSTAB_LO(as_nr), transtab & 0xffffffffUL);
+	mmu_write(pfdev, AS_TRANSTAB_HI(as_nr), transtab >> 32);
+
+	/* Need to revisit mem attrs.
+	 * NC is the default, Mali driver is inner WT.
+	 */
+	mmu_write(pfdev, AS_MEMATTR_LO(as_nr), memattr & 0xffffffffUL);
+	mmu_write(pfdev, AS_MEMATTR_HI(as_nr), memattr >> 32);
+
+	write_cmd(pfdev, as_nr, AS_COMMAND_UPDATE);
+}
+
+static void mmu_disable(struct panfrost_device *pfdev, u32 as_nr)
+{
+	mmu_write(pfdev, AS_TRANSTAB_LO(as_nr), 0);
+	mmu_write(pfdev, AS_TRANSTAB_HI(as_nr), 0);
+
+	mmu_write(pfdev, AS_MEMATTR_LO(as_nr), 0);
+	mmu_write(pfdev, AS_MEMATTR_HI(as_nr), 0);
+
+	write_cmd(pfdev, as_nr, AS_COMMAND_UPDATE);
+}
+
+int panfrost_mmu_map(struct panfrost_gem_object *bo)
+{
+	struct drm_gem_object *obj = &bo->base.base;
+	struct panfrost_device *pfdev = to_panfrost_device(obj->dev);
+	struct io_pgtable_ops *ops = pfdev->mmu->pgtbl_ops;
+	u64 iova = bo->node.start << PAGE_SHIFT;
+	unsigned int count;
+	struct scatterlist *sgl;
+	struct sg_table *sgt;
+	int ret;
+
+	sgt = drm_gem_shmem_get_pages_sgt(obj);
+	if (WARN_ON(IS_ERR(sgt)))
+		return PTR_ERR(sgt);
+
+	ret = pm_runtime_get_sync(pfdev->dev);
+	if (ret < 0)
+		return ret;
+
+	mutex_lock(&pfdev->mmu->lock);
+
+	for_each_sg(sgt->sgl, sgl, sgt->nents, count) {
+		unsigned long paddr = sg_dma_address(sgl);
+		size_t len = sg_dma_len(sgl);
+
+		while (len) {
+			dev_dbg(pfdev->dev, "map: iova=%llx, paddr=%lx, len=%zx", iova, paddr, len);
+			ops->map(ops, iova, paddr, SZ_4K, IOMMU_WRITE | IOMMU_READ);
+			iova += SZ_4K;
+			paddr += SZ_4K;
+			len -= SZ_4K;
+		}
+	}
+
+	mutex_unlock(&pfdev->mmu->lock);
+
+	pm_runtime_mark_last_busy(pfdev->dev);
+	pm_runtime_put_autosuspend(pfdev->dev);
+
+	return 0;
+}
+
+void panfrost_mmu_unmap(struct panfrost_gem_object *bo)
+{
+	struct drm_gem_object *obj = &bo->base.base;
+	struct panfrost_device *pfdev = to_panfrost_device(obj->dev);
+	struct io_pgtable_ops *ops = pfdev->mmu->pgtbl_ops;
+	u64 iova = bo->node.start << PAGE_SHIFT;
+	size_t len = bo->node.size << PAGE_SHIFT;
+	size_t unmapped_len = 0;
+	int ret;
+
+	ret = pm_runtime_get_sync(pfdev->dev);
+	if (ret < 0)
+		return;
+
+	mutex_lock(&pfdev->mmu->lock);
+
+	while (unmapped_len < len) {
+		ops->unmap(ops, iova, SZ_4K);
+		iova += SZ_4K;
+		unmapped_len += SZ_4K;
+	}
+
+	mutex_unlock(&pfdev->mmu->lock);
+
+	pm_runtime_mark_last_busy(pfdev->dev);
+	pm_runtime_put_autosuspend(pfdev->dev);
+}
+
+static void mmu_tlb_inv_context_s1(void *cookie)
+{
+	struct panfrost_device *pfdev = cookie;
+
+	mmu_hw_do_operation(pfdev, 0, 0, ~0UL, AS_COMMAND_FLUSH_MEM);
+}
+
+static void mmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
+				     size_t granule, bool leaf, void *cookie)
+{
+	struct panfrost_device *pfdev = cookie;
+
+	dev_dbg(pfdev->dev, "inv_range: iova=%lx, size=%zx, granule=%zx, leaf=%d",
+		iova, size, granule, leaf);
+	mmu_hw_do_operation(pfdev, 0, iova, size, AS_COMMAND_FLUSH_PT);
+}
+
+static void mmu_tlb_sync_context(void *cookie)
+{
+	//struct panfrost_device *pfdev = cookie;
+	// Wait 1000 GPU cycles!?
+}
+
+static const struct iommu_gather_ops mmu_tlb_ops = {
+	.tlb_flush_all	= mmu_tlb_inv_context_s1,
+	.tlb_add_flush	= mmu_tlb_inv_range_nosync,
+	.tlb_sync	= mmu_tlb_sync_context,
+};
+
+static const char *access_type_name(struct panfrost_device *pfdev,
+		u32 fault_status)
+{
+	switch (fault_status & AS_FAULTSTATUS_ACCESS_TYPE_MASK) {
+	case AS_FAULTSTATUS_ACCESS_TYPE_ATOMIC:
+		if (panfrost_has_hw_feature(pfdev, HW_FEATURE_AARCH64_MMU))
+			return "ATOMIC";
+		else
+			return "UNKNOWN";
+	case AS_FAULTSTATUS_ACCESS_TYPE_READ:
+		return "READ";
+	case AS_FAULTSTATUS_ACCESS_TYPE_WRITE:
+		return "WRITE";
+	case AS_FAULTSTATUS_ACCESS_TYPE_EX:
+		return "EXECUTE";
+	default:
+		WARN_ON(1);
+		return NULL;
+	}
+}
+
+static irqreturn_t panfrost_mmu_irq_handler(int irq, void *data)
+{
+	struct panfrost_device *pfdev = data;
+	u32 status = mmu_read(pfdev, MMU_INT_STAT);
+	int i;
+
+	if (!status)
+		return IRQ_NONE;
+
+	dev_err(pfdev->dev, "mmu irq status=%x\n", status);
+
+	for (i = 0; status; i++) {
+		u32 mask = BIT(i) | BIT(i + 16);
+		u64 addr;
+		u32 fault_status;
+		u32 exception_type;
+		u32 access_type;
+		u32 source_id;
+
+		if (!(status & mask))
+			continue;
+
+		fault_status = mmu_read(pfdev, AS_FAULTSTATUS(i));
+		addr = mmu_read(pfdev, AS_FAULTADDRESS_LO(i));
+		addr |= (u64)mmu_read(pfdev, AS_FAULTADDRESS_HI(i)) << 32;
+
+		/* decode the fault status */
+		exception_type = fault_status & 0xFF;
+		access_type = (fault_status >> 8) & 0x3;
+		source_id = (fault_status >> 16);
+
+		/* terminal fault, print info about the fault */
+		dev_err(pfdev->dev,
+			"Unhandled Page fault in AS%d at VA 0x%016llX\n"
+			"Reason: %s\n"
+			"raw fault status: 0x%X\n"
+			"decoded fault status: %s\n"
+			"exception type 0x%X: %s\n"
+			"access type 0x%X: %s\n"
+			"source id 0x%X\n",
+			i, addr,
+			"TODO",
+			fault_status,
+			(fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
+			exception_type, panfrost_exception_name(pfdev, exception_type),
+			access_type, access_type_name(pfdev, fault_status),
+			source_id);
+
+		mmu_write(pfdev, MMU_INT_CLEAR, mask);
+
+		status &= ~mask;
+	}
+
+	return IRQ_HANDLED;
+};
+
+int panfrost_mmu_init(struct panfrost_device *pfdev)
+{
+	struct io_pgtable_ops *pgtbl_ops;
+	int err, irq;
+
+	pfdev->mmu = devm_kzalloc(pfdev->dev, sizeof(*pfdev->mmu), GFP_KERNEL);
+	if (!pfdev->mmu)
+		return -ENOMEM;
+
+	mutex_init(&pfdev->mmu->lock);
+
+	irq = platform_get_irq_byname(to_platform_device(pfdev->dev), "mmu");
+	if (irq <= 0)
+		return -ENODEV;
+
+	err = devm_request_irq(pfdev->dev, irq, panfrost_mmu_irq_handler,
+			       IRQF_SHARED, "mmu", pfdev);
+
+	if (err) {
+		dev_err(pfdev->dev, "failed to request mmu irq");
+		return err;
+	}
+	mmu_write(pfdev, MMU_INT_CLEAR, ~0);
+	mmu_write(pfdev, MMU_INT_MASK, ~0);
+
+	pfdev->mmu->pgtbl_cfg = (struct io_pgtable_cfg) {
+		.pgsize_bitmap	= SZ_4K, // | SZ_2M | SZ_1G),
+		.ias		= 48,
+		.oas		= 40,	/* Should come from dma mask? */
+		.tlb		= &mmu_tlb_ops,
+		.iommu_dev	= pfdev->dev,
+	};
+
+	pgtbl_ops = alloc_io_pgtable_ops(ARM_MALI_LPAE, &pfdev->mmu->pgtbl_cfg,
+					 pfdev);
+	if (!pgtbl_ops)
+		return -ENOMEM;
+
+	pfdev->mmu->pgtbl_ops = pgtbl_ops;
+
+	panfrost_mmu_enable(pfdev, 0);
+
+	return 0;
+}
+
+void panfrost_mmu_fini(struct panfrost_device *pfdev)
+{
+	mmu_write(pfdev, MMU_INT_MASK, 0);
+	mmu_disable(pfdev, 0);
+
+	free_io_pgtable_ops(pfdev->mmu->pgtbl_ops);
+}
diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.h b/drivers/gpu/drm/panfrost/panfrost_mmu.h
new file mode 100644
index 000000000000..f5878d86a5ce
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.h
@@ -0,0 +1,17 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+
+#ifndef __PANFROST_MMU_H__
+#define __PANFROST_MMU_H__
+
+struct panfrost_gem_object;
+
+int panfrost_mmu_map(struct panfrost_gem_object *bo);
+void panfrost_mmu_unmap(struct panfrost_gem_object *bo);
+
+int panfrost_mmu_init(struct panfrost_device *pfdev);
+void panfrost_mmu_fini(struct panfrost_device *pfdev);
+
+void panfrost_mmu_enable(struct panfrost_device *pfdev, u32 as_nr);
+
+#endif
diff --git a/drivers/gpu/drm/panfrost/panfrost_regs.h b/drivers/gpu/drm/panfrost/panfrost_regs.h
new file mode 100644
index 000000000000..578c5fc2188b
--- /dev/null
+++ b/drivers/gpu/drm/panfrost/panfrost_regs.h
@@ -0,0 +1,298 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+/*
+ * Register definitions based on mali_midg_regmap.h
+ * (C) COPYRIGHT 2010-2018 ARM Limited. All rights reserved.
+ */
+#ifndef __PANFROST_REGS_H__
+#define __PANFROST_REGS_H__
+
+#define GPU_ID				0x00
+#define GPU_L2_FEATURES			0x004	/* (RO) Level 2 cache features */
+#define GPU_CORE_FEATURES		0x008	/* (RO) Shader Core Features */
+#define GPU_TILER_FEATURES		0x00C	/* (RO) Tiler Features */
+#define GPU_MEM_FEATURES		0x010	/* (RO) Memory system features */
+#define   GROUPS_L2_COHERENT		BIT(0)	/* Cores groups are l2 coherent */
+
+#define GPU_MMU_FEATURES		0x014	/* (RO) MMU features */
+#define GPU_AS_PRESENT			0x018	/* (RO) Address space slots present */
+#define GPU_JS_PRESENT			0x01C	/* (RO) Job slots present */
+
+#define GPU_INT_RAWSTAT			0x20
+#define GPU_INT_CLEAR			0x24
+#define GPU_INT_MASK			0x28
+#define GPU_INT_STAT			0x2c
+#define   GPU_IRQ_FAULT			BIT(0)
+#define   GPU_IRQ_MULTIPLE_FAULT	BIT(7)
+#define   GPU_IRQ_RESET_COMPLETED	BIT(8)
+#define   GPU_IRQ_POWER_CHANGED		BIT(9)
+#define   GPU_IRQ_POWER_CHANGED_ALL	BIT(10)
+#define   GPU_IRQ_PERFCNT_SAMPLE_COMPLETED BIT(16)
+#define   GPU_IRQ_CLEAN_CACHES_COMPLETED BIT(17)
+#define   GPU_IRQ_MASK_ALL			 \
+	  (GPU_IRQ_FAULT			|\
+	   GPU_IRQ_MULTIPLE_FAULT		|\
+	   GPU_IRQ_RESET_COMPLETED		|\
+	   GPU_IRQ_POWER_CHANGED		|\
+	   GPU_IRQ_POWER_CHANGED_ALL		|\
+	   GPU_IRQ_PERFCNT_SAMPLE_COMPLETED	|\
+	   GPU_IRQ_CLEAN_CACHES_COMPLETED)
+#define GPU_IRQ_MASK_ERROR	   		\
+	(					\
+	 GPU_IRQ_FAULT				|\
+	 GPU_IRQ_MULTIPLE_FAULT)
+#define GPU_CMD				0x30
+#define   GPU_CMD_SOFT_RESET		0x01
+#define GPU_STATUS			0x34
+#define GPU_LATEST_FLUSH_ID		0x38
+#define GPU_FAULT_STATUS		0x3C
+#define GPU_FAULT_ADDRESS_LO		0x40
+#define GPU_FAULT_ADDRESS_HI		0x44
+
+#define GPU_THREAD_MAX_THREADS		0x0A0	/* (RO) Maximum number of threads per core */
+#define GPU_THREAD_MAX_WORKGROUP_SIZE	0x0A4	/* (RO) Maximum workgroup size */
+#define GPU_THREAD_MAX_BARRIER_SIZE	0x0A8	/* (RO) Maximum threads waiting at a barrier */
+#define GPU_THREAD_FEATURES		0x0AC	/* (RO) Thread features */
+#define GPU_THREAD_TLS_ALLOC		0x310   /* (RO) Number of threads per core that
+						 * TLS must be allocated for */
+
+#define GPU_TEXTURE_FEATURES(n)		(0x0B0 + ((n) * 4))
+#define GPU_JS_FEATURES(n)		(0x0C0 + ((n) * 4))
+
+#define GPU_SHADER_PRESENT_LO		0x100	/* (RO) Shader core present bitmap, low word */
+#define GPU_SHADER_PRESENT_HI		0x104	/* (RO) Shader core present bitmap, high word */
+#define GPU_TILER_PRESENT_LO		0x110	/* (RO) Tiler core present bitmap, low word */
+#define GPU_TILER_PRESENT_HI		0x114	/* (RO) Tiler core present bitmap, high word */
+
+#define GPU_L2_PRESENT_LO		0x120	/* (RO) Level 2 cache present bitmap, low word */
+#define GPU_L2_PRESENT_HI		0x124	/* (RO) Level 2 cache present bitmap, high word */
+
+#define GPU_COHERENCY_FEATURES		0x300	/* (RO) Coherency features present */
+#define   COHERENCY_ACE_LITE		BIT(0)
+#define   COHERENCY_ACE			BIT(1)
+
+#define GPU_STACK_PRESENT_LO		0xE00   /* (RO) Core stack present bitmap, low word */
+#define GPU_STACK_PRESENT_HI		0xE04   /* (RO) Core stack present bitmap, high word */
+
+#define SHADER_READY_LO			0x140	/* (RO) Shader core ready bitmap, low word */
+#define SHADER_READY_HI			0x144	/* (RO) Shader core ready bitmap, high word */
+
+#define TILER_READY_LO			0x150	/* (RO) Tiler core ready bitmap, low word */
+#define TILER_READY_HI			0x154	/* (RO) Tiler core ready bitmap, high word */
+
+#define L2_READY_LO			0x160	/* (RO) Level 2 cache ready bitmap, low word */
+#define L2_READY_HI			0x164	/* (RO) Level 2 cache ready bitmap, high word */
+
+#define STACK_READY_LO			0xE10   /* (RO) Core stack ready bitmap, low word */
+#define STACK_READY_HI			0xE14   /* (RO) Core stack ready bitmap, high word */
+
+
+#define SHADER_PWRON_LO			0x180	/* (WO) Shader core power on bitmap, low word */
+#define SHADER_PWRON_HI			0x184	/* (WO) Shader core power on bitmap, high word */
+
+#define TILER_PWRON_LO			0x190	/* (WO) Tiler core power on bitmap, low word */
+#define TILER_PWRON_HI			0x194	/* (WO) Tiler core power on bitmap, high word */
+
+#define L2_PWRON_LO			0x1A0	/* (WO) Level 2 cache power on bitmap, low word */
+#define L2_PWRON_HI			0x1A4	/* (WO) Level 2 cache power on bitmap, high word */
+
+#define STACK_PWRON_LO			0xE20   /* (RO) Core stack power on bitmap, low word */
+#define STACK_PWRON_HI			0xE24   /* (RO) Core stack power on bitmap, high word */
+
+
+#define SHADER_PWROFF_LO		0x1C0	/* (WO) Shader core power off bitmap, low word */
+#define SHADER_PWROFF_HI		0x1C4	/* (WO) Shader core power off bitmap, high word */
+
+#define TILER_PWROFF_LO			0x1D0	/* (WO) Tiler core power off bitmap, low word */
+#define TILER_PWROFF_HI			0x1D4	/* (WO) Tiler core power off bitmap, high word */
+
+#define L2_PWROFF_LO			0x1E0	/* (WO) Level 2 cache power off bitmap, low word */
+#define L2_PWROFF_HI			0x1E4	/* (WO) Level 2 cache power off bitmap, high word */
+
+#define STACK_PWROFF_LO			0xE30   /* (RO) Core stack power off bitmap, low word */
+#define STACK_PWROFF_HI			0xE34   /* (RO) Core stack power off bitmap, high word */
+
+
+#define SHADER_PWRTRANS_LO		0x200	/* (RO) Shader core power transition bitmap, low word */
+#define SHADER_PWRTRANS_HI		0x204	/* (RO) Shader core power transition bitmap, high word */
+
+#define TILER_PWRTRANS_LO		0x210	/* (RO) Tiler core power transition bitmap, low word */
+#define TILER_PWRTRANS_HI		0x214	/* (RO) Tiler core power transition bitmap, high word */
+
+#define L2_PWRTRANS_LO			0x220	/* (RO) Level 2 cache power transition bitmap, low word */
+#define L2_PWRTRANS_HI			0x224	/* (RO) Level 2 cache power transition bitmap, high word */
+
+#define STACK_PWRTRANS_LO		0xE40   /* (RO) Core stack power transition bitmap, low word */
+#define STACK_PWRTRANS_HI		0xE44   /* (RO) Core stack power transition bitmap, high word */
+
+
+#define SHADER_PWRACTIVE_LO		0x240	/* (RO) Shader core active bitmap, low word */
+#define SHADER_PWRACTIVE_HI		0x244	/* (RO) Shader core active bitmap, high word */
+
+#define TILER_PWRACTIVE_LO		0x250	/* (RO) Tiler core active bitmap, low word */
+#define TILER_PWRACTIVE_HI		0x254	/* (RO) Tiler core active bitmap, high word */
+
+#define L2_PWRACTIVE_LO			0x260	/* (RO) Level 2 cache active bitmap, low word */
+#define L2_PWRACTIVE_HI			0x264	/* (RO) Level 2 cache active bitmap, high word */
+
+#define GPU_JM_CONFIG			0xF00   /* (RW) Job Manager configuration register (Implementation specific register) */
+#define GPU_SHADER_CONFIG		0xF04	/* (RW) Shader core configuration settings (Implementation specific register) */
+#define GPU_TILER_CONFIG		0xF08   /* (RW) Tiler core configuration settings (Implementation specific register) */
+#define GPU_L2_MMU_CONFIG		0xF0C	/* (RW) Configuration of the L2 cache and MMU (Implementation specific register) */
+
+/* L2_MMU_CONFIG register */
+#define L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY_SHIFT	23
+#define L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY		(0x1 << L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY_SHIFT)
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT	24
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS		(0x3 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_OCTANT	(0x1 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_QUARTER	(0x2 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_HALF		(0x3 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
+
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT	26
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES		(0x3 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_OCTANT	(0x1 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_QUARTER	(0x2 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
+#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_HALF	(0x3 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
+
+#define L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_READS_SHIFT	12
+#define L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_READS		(0x7 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
+
+#define L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_WRITES_SHIFT	15
+#define L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_WRITES	(0x7 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
+
+/* SHADER_CONFIG register */
+#define SC_ALT_COUNTERS			BIT(3)
+#define SC_OVERRIDE_FWD_PIXEL_KILL	BIT(4)
+#define SC_SDC_DISABLE_OQ_DISCARD	BIT(6)
+#define SC_LS_ALLOW_ATTR_TYPES		BIT(16)
+#define SC_LS_PAUSEBUFFER_DISABLE	BIT(16)
+#define SC_TLS_HASH_ENABLE		BIT(17)
+#define SC_LS_ATTR_CHECK_DISABLE	BIT(18)
+#define SC_ENABLE_TEXGRD_FLAGS		BIT(25)
+/* End SHADER_CONFIG register */
+
+/* TILER_CONFIG register */
+#define TC_CLOCK_GATE_OVERRIDE		BIT(0)
+
+/* JM_CONFIG register */
+#define JM_TIMESTAMP_OVERRIDE		BIT(0)
+#define JM_CLOCK_GATE_OVERRIDE		BIT(1)
+#define JM_JOB_THROTTLE_ENABLE		BIT(2)
+#define JM_JOB_THROTTLE_LIMIT_SHIFT	3
+#define JM_MAX_JOB_THROTTLE_LIMIT	0x3F
+#define JM_FORCE_COHERENCY_FEATURES_SHIFT 2
+#define JM_IDVS_GROUP_SIZE_SHIFT	16
+#define JM_MAX_IDVS_GROUP_SIZE		0x3F
+
+
+/* Job Control regs */
+#define JOB_INT_RAWSTAT			0x1000
+#define JOB_INT_CLEAR			0x1004
+#define JOB_INT_MASK			0x1008
+#define JOB_INT_STAT			0x100c
+#define JOB_INT_JS_STATE		0x1010
+#define JOB_INT_THROTTLE		0x1014
+
+#define MK_JS_MASK(j)			(0x10001 << (j))
+#define JOB_INT_MASK_ERR(j)		BIT((j) + 16)
+#define JOB_INT_MASK_DONE(j)		BIT(j)
+
+#define JS_BASE				0x1800
+#define JS_HEAD_LO(n)			(JS_BASE + ((n) * 0x80) + 0x00)
+#define JS_HEAD_HI(n)			(JS_BASE + ((n) * 0x80) + 0x04)
+#define JS_TAIL_LO(n)			(JS_BASE + ((n) * 0x80) + 0x08)
+#define JS_TAIL_HI(n)			(JS_BASE + ((n) * 0x80) + 0x0c)
+#define JS_AFFINITY_LO(n)		(JS_BASE + ((n) * 0x80) + 0x10)
+#define JS_AFFINITY_HI(n)		(JS_BASE + ((n) * 0x80) + 0x14)
+#define JS_CONFIG(n)			(JS_BASE + ((n) * 0x80) + 0x18)
+#define JS_XAFFINITY(n)			(JS_BASE + ((n) * 0x80) + 0x1c)
+#define JS_COMMAND(n)			(JS_BASE + ((n) * 0x80) + 0x20)
+#define JS_STATUS(n)			(JS_BASE + ((n) * 0x80) + 0x24)
+#define JS_HEAD_NEXT_LO(n)		(JS_BASE + ((n) * 0x80) + 0x40)
+#define JS_HEAD_NEXT_HI(n)		(JS_BASE + ((n) * 0x80) + 0x44)
+#define JS_AFFINITY_NEXT_LO(n)		(JS_BASE + ((n) * 0x80) + 0x50)
+#define JS_AFFINITY_NEXT_HI(n)		(JS_BASE + ((n) * 0x80) + 0x54)
+#define JS_CONFIG_NEXT(n)		(JS_BASE + ((n) * 0x80) + 0x58)
+#define JS_COMMAND_NEXT(n)		(JS_BASE + ((n) * 0x80) + 0x60)
+#define JS_FLUSH_ID_NEXT(n)		(JS_BASE + ((n) * 0x80) + 0x70)
+
+/* Possible values of JS_CONFIG and JS_CONFIG_NEXT registers */
+#define JS_CONFIG_START_FLUSH_CLEAN		BIT(8)
+#define JS_CONFIG_START_FLUSH_CLEAN_INVALIDATE	(3u << 8)
+#define JS_CONFIG_START_MMU			BIT(10)
+#define JS_CONFIG_JOB_CHAIN_FLAG		BIT(11)
+#define JS_CONFIG_END_FLUSH_CLEAN		BIT(12)
+#define JS_CONFIG_END_FLUSH_CLEAN_INVALIDATE	(3u << 12)
+#define JS_CONFIG_ENABLE_FLUSH_REDUCTION	BIT(14)
+#define JS_CONFIG_DISABLE_DESCRIPTOR_WR_BK	BIT(15)
+#define JS_CONFIG_THREAD_PRI(n)			((n) << 16)
+
+#define JS_COMMAND_NOP			0x00
+#define JS_COMMAND_START		0x01
+#define JS_COMMAND_SOFT_STOP		0x02	/* Gently stop processing a job chain */
+#define JS_COMMAND_HARD_STOP		0x03	/* Rudely stop processing a job chain */
+#define JS_COMMAND_SOFT_STOP_0		0x04	/* Execute SOFT_STOP if JOB_CHAIN_FLAG is 0 */
+#define JS_COMMAND_HARD_STOP_0		0x05	/* Execute HARD_STOP if JOB_CHAIN_FLAG is 0 */
+#define JS_COMMAND_SOFT_STOP_1		0x06	/* Execute SOFT_STOP if JOB_CHAIN_FLAG is 1 */
+#define JS_COMMAND_HARD_STOP_1		0x07	/* Execute HARD_STOP if JOB_CHAIN_FLAG is 1 */
+
+#define JS_STATUS_EVENT_ACTIVE		0x08
+
+
+/* MMU regs */
+#define MMU_INT_RAWSTAT			0x2000
+#define MMU_INT_CLEAR			0x2004
+#define MMU_INT_MASK			0x2008
+#define MMU_INT_STAT			0x200c
+
+/* AS_COMMAND register commands */
+#define AS_COMMAND_NOP			0x00	/* NOP Operation */
+#define AS_COMMAND_UPDATE		0x01	/* Broadcasts the values in AS_TRANSTAB and ASn_MEMATTR to all MMUs */
+#define AS_COMMAND_LOCK			0x02	/* Issue a lock region command to all MMUs */
+#define AS_COMMAND_UNLOCK		0x03	/* Issue a flush region command to all MMUs */
+#define AS_COMMAND_FLUSH		0x04	/* Flush all L2 caches then issue a flush region command to all MMUs
+						   (deprecated - only for use with T60x) */
+#define AS_COMMAND_FLUSH_PT		0x04	/* Flush all L2 caches then issue a flush region command to all MMUs */
+#define AS_COMMAND_FLUSH_MEM		0x05	/* Wait for memory accesses to complete, flush all the L1s cache then
+						   flush all L2 caches then issue a flush region command to all MMUs */
+
+#define MMU_AS(as)			(0x2400 + ((as) << 6))
+
+#define AS_TRANSTAB_LO(as)		(MMU_AS(as) + 0x00) /* (RW) Translation Table Base Address for address space n, low word */
+#define AS_TRANSTAB_HI(as)		(MMU_AS(as) + 0x04) /* (RW) Translation Table Base Address for address space n, high word */
+#define AS_MEMATTR_LO(as)		(MMU_AS(as) + 0x08) /* (RW) Memory attributes for address space n, low word. */
+#define AS_MEMATTR_HI(as)		(MMU_AS(as) + 0x0C) /* (RW) Memory attributes for address space n, high word. */
+#define AS_LOCKADDR_LO(as)		(MMU_AS(as) + 0x10) /* (RW) Lock region address for address space n, low word */
+#define AS_LOCKADDR_HI(as)		(MMU_AS(as) + 0x14) /* (RW) Lock region address for address space n, high word */
+#define AS_COMMAND(as)			(MMU_AS(as) + 0x18) /* (WO) MMU command register for address space n */
+#define AS_FAULTSTATUS(as)		(MMU_AS(as) + 0x1C) /* (RO) MMU fault status register for address space n */
+#define AS_FAULTADDRESS_LO(as)		(MMU_AS(as) + 0x20) /* (RO) Fault Address for address space n, low word */
+#define AS_FAULTADDRESS_HI(as)		(MMU_AS(as) + 0x24) /* (RO) Fault Address for address space n, high word */
+#define AS_STATUS(as)			(MMU_AS(as) + 0x28) /* (RO) Status flags for address space n */
+/* Additional Bifrost AS regsiters */
+#define AS_TRANSCFG_LO(as)		(MMU_AS(as) + 0x30) /* (RW) Translation table configuration for address space n, low word */
+#define AS_TRANSCFG_HI(as)		(MMU_AS(as) + 0x34) /* (RW) Translation table configuration for address space n, high word */
+#define AS_FAULTEXTRA_LO(as)		(MMU_AS(as) + 0x38) /* (RO) Secondary fault address for address space n, low word */
+#define AS_FAULTEXTRA_HI(as)		(MMU_AS(as) + 0x3C) /* (RO) Secondary fault address for address space n, high word */
+
+/*
+ * Begin LPAE MMU TRANSTAB register values
+ */
+#define AS_TRANSTAB_LPAE_ADDR_SPACE_MASK	0xfffffffffffff000
+#define AS_TRANSTAB_LPAE_ADRMODE_IDENTITY	0x2
+#define AS_TRANSTAB_LPAE_ADRMODE_TABLE		0x3
+#define AS_TRANSTAB_LPAE_ADRMODE_MASK		0x3
+#define AS_TRANSTAB_LPAE_READ_INNER		BIT(2)
+#define AS_TRANSTAB_LPAE_SHARE_OUTER		BIT(4)
+
+#define AS_STATUS_AS_ACTIVE			0x01
+
+#define AS_FAULTSTATUS_ACCESS_TYPE_MASK		(0x3 << 8)
+#define AS_FAULTSTATUS_ACCESS_TYPE_ATOMIC	(0x0 << 8)
+#define AS_FAULTSTATUS_ACCESS_TYPE_EX		(0x1 << 8)
+#define AS_FAULTSTATUS_ACCESS_TYPE_READ		(0x2 << 8)
+#define AS_FAULTSTATUS_ACCESS_TYPE_WRITE	(0x3 << 8)
+
+#endif
diff --git a/include/uapi/drm/panfrost_drm.h b/include/uapi/drm/panfrost_drm.h
new file mode 100644
index 000000000000..508b9621d9db
--- /dev/null
+++ b/include/uapi/drm/panfrost_drm.h
@@ -0,0 +1,140 @@ 
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2014-2018 Broadcom
+ * Copyright © 2019 Collabora ltd.
+ */
+#ifndef _PANFROST_DRM_H_
+#define _PANFROST_DRM_H_
+
+#include "drm.h"
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+#define DRM_PANFROST_SUBMIT			0x00
+#define DRM_PANFROST_WAIT_BO			0x01
+#define DRM_PANFROST_CREATE_BO			0x02
+#define DRM_PANFROST_MMAP_BO			0x03
+#define DRM_PANFROST_GET_PARAM			0x04
+#define DRM_PANFROST_GET_BO_OFFSET		0x05
+
+#define DRM_IOCTL_PANFROST_SUBMIT		DRM_IOW(DRM_COMMAND_BASE + DRM_PANFROST_SUBMIT, struct drm_panfrost_submit)
+#define DRM_IOCTL_PANFROST_WAIT_BO		DRM_IOW(DRM_COMMAND_BASE + DRM_PANFROST_WAIT_BO, struct drm_panfrost_wait_bo)
+#define DRM_IOCTL_PANFROST_CREATE_BO		DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_CREATE_BO, struct drm_panfrost_create_bo)
+#define DRM_IOCTL_PANFROST_MMAP_BO		DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_MMAP_BO, struct drm_panfrost_mmap_bo)
+#define DRM_IOCTL_PANFROST_GET_PARAM		DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_GET_PARAM, struct drm_panfrost_get_param)
+#define DRM_IOCTL_PANFROST_GET_BO_OFFSET	DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_GET_BO_OFFSET, struct drm_panfrost_get_bo_offset)
+
+#define PANFROST_JD_REQ_FS (1 << 0)
+/**
+ * struct drm_panfrost_submit - ioctl argument for submitting commands to the 3D
+ * engine.
+ *
+ * This asks the kernel to have the GPU execute a render command list.
+ */
+struct drm_panfrost_submit {
+
+	/** Address to GPU mapping of job descriptor */
+	__u64 jc;
+
+	/** An optional array of sync objects to wait on before starting this job. */
+	__u64 in_syncs;
+
+	/** Number of sync objects to wait on before starting this job. */
+	__u32 in_sync_count;
+
+	/** An optional sync object to place the completion fence in. */
+	__u32 out_sync;
+
+	/** Pointer to a u32 array of the BOs that are referenced by the job. */
+	__u64 bo_handles;
+
+	/** Number of BO handles passed in (size is that times 4). */
+	__u32 bo_handle_count;
+
+	/** A combination of PANFROST_JD_REQ_* */
+	__u32 requirements;
+};
+
+/**
+ * struct drm_panfrost_wait_bo - ioctl argument for waiting for
+ * completion of the last DRM_PANFROST_SUBMIT_CL on a BO.
+ *
+ * This is useful for cases where multiple processes might be
+ * rendering to a BO and you want to wait for all rendering to be
+ * completed.
+ */
+struct drm_panfrost_wait_bo {
+	__u32 handle;
+	__u32 pad;
+	__s64 timeout_ns;	/* absolute */
+};
+
+/**
+ * struct drm_panfrost_create_bo - ioctl argument for creating Panfrost BOs.
+ *
+ * There are currently no values for the flags argument, but it may be
+ * used in a future extension.
+ */
+struct drm_panfrost_create_bo {
+	__u32 size;
+	__u32 flags;
+	/** Returned GEM handle for the BO. */
+	__u32 handle;
+	/**
+	 * Returned offset for the BO in the GPU address space.  This offset
+	 * is private to the DRM fd and is valid for the lifetime of the GEM
+	 * handle.
+	 *
+	 * This offset value will always be nonzero, since various HW
+	 * units treat 0 specially.
+	 */
+	__u64 offset;
+};
+
+/**
+ * struct drm_panfrost_mmap_bo - ioctl argument for mapping Panfrost BOs.
+ *
+ * This doesn't actually perform an mmap.  Instead, it returns the
+ * offset you need to use in an mmap on the DRM device node.  This
+ * means that tools like valgrind end up knowing about the mapped
+ * memory.
+ *
+ * There are currently no values for the flags argument, but it may be
+ * used in a future extension.
+ */
+struct drm_panfrost_mmap_bo {
+	/** Handle for the object being mapped. */
+	__u32 handle;
+	__u32 flags;
+	/** offset into the drm node to use for subsequent mmap call. */
+	__u64 offset;
+};
+
+enum drm_panfrost_param {
+	DRM_PANFROST_PARAM_GPU_ID,
+};
+
+struct drm_panfrost_get_param {
+	__u32 param;
+	__u32 pad;
+	__u64 value;
+};
+
+/**
+ * Returns the offset for the BO in the GPU address space for this DRM fd.
+ * This is the same value returned by drm_panfrost_create_bo, if that was called
+ * from this DRM fd.
+ */
+struct drm_panfrost_get_bo_offset {
+	__u32 handle;
+	__u32 pad;
+	__u64 offset;
+};
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* _PANFROST_DRM_H_ */

Comments

On 01/04/2019 09:47, Rob Herring wrote:
> This adds the initial driver for panfrost which supports Arm Mali
> Midgard and Bifrost family of GPUs. Currently, only the T860 and
> T760 Midgard GPUs have been tested.
> 
> v2:
> - Add GPU reset on job hangs (Tomeu)
> - Add RuntimePM and devfreq support (Tomeu)
> - Fix T760 support (Tomeu)
> - Add a TODO file (Rob, Tomeu)
> - Support multiple in fences (Tomeu)
> - Drop support for shared fences (Tomeu)
> - Fill in MMU de-init (Rob)
> - Move register definitions back to single header (Rob)
> - Clean-up hardcoded job submit todos (Rob)
> - Implement feature setup based on features/issues (Rob)
> - Add remaining Midgard DT compatible strings (Rob)
> 
> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> Cc: Maxime Ripard <maxime.ripard@bootlin.com>
> Cc: Sean Paul <sean@poorly.run>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> Cc: Lyude Paul <lyude@redhat.com>
> Cc: Eric Anholt <eric@anholt.net>
> Signed-off-by: Marty E. Plummer <hanetzer@startmail.com>
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---
> Neil, I've kept your reset support separate for now. Let me know if you
> prefer me to squash it or keep it separate.

You can squash all my changes and add my sign-off.

Neil

> 
>  drivers/gpu/drm/Kconfig                      |   2 +
>  drivers/gpu/drm/Makefile                     |   1 +
>  drivers/gpu/drm/panfrost/Kconfig             |  14 +
>  drivers/gpu/drm/panfrost/Makefile            |  12 +
>  drivers/gpu/drm/panfrost/TODO                |  27 +
>  drivers/gpu/drm/panfrost/panfrost_devfreq.c  | 191 +++++++
>  drivers/gpu/drm/panfrost/panfrost_devfreq.h  |  14 +
>  drivers/gpu/drm/panfrost/panfrost_device.c   | 227 ++++++++
>  drivers/gpu/drm/panfrost/panfrost_device.h   | 118 ++++
>  drivers/gpu/drm/panfrost/panfrost_drv.c      | 484 ++++++++++++++++
>  drivers/gpu/drm/panfrost/panfrost_features.h | 309 +++++++++++
>  drivers/gpu/drm/panfrost/panfrost_gem.c      |  92 +++
>  drivers/gpu/drm/panfrost/panfrost_gem.h      |  29 +
>  drivers/gpu/drm/panfrost/panfrost_gpu.c      | 374 +++++++++++++
>  drivers/gpu/drm/panfrost/panfrost_gpu.h      |  19 +
>  drivers/gpu/drm/panfrost/panfrost_issues.h   | 176 ++++++
>  drivers/gpu/drm/panfrost/panfrost_job.c      | 556 +++++++++++++++++++
>  drivers/gpu/drm/panfrost/panfrost_job.h      |  51 ++
>  drivers/gpu/drm/panfrost/panfrost_mmu.c      | 366 ++++++++++++
>  drivers/gpu/drm/panfrost/panfrost_mmu.h      |  17 +
>  drivers/gpu/drm/panfrost/panfrost_regs.h     | 298 ++++++++++
>  include/uapi/drm/panfrost_drm.h              | 140 +++++
>  22 files changed, 3517 insertions(+)
>  create mode 100644 drivers/gpu/drm/panfrost/Kconfig
>  create mode 100644 drivers/gpu/drm/panfrost/Makefile
>  create mode 100644 drivers/gpu/drm/panfrost/TODO
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_devfreq.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_devfreq.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_device.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_device.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_drv.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_features.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_gem.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_gem.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_gpu.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_gpu.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_issues.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_job.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_job.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_mmu.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_mmu.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_regs.h
>  create mode 100644 include/uapi/drm/panfrost_drm.h
> 
[...]

On 01/04/2019 08:47, Rob Herring wrote:
> This adds the initial driver for panfrost which supports Arm Mali
> Midgard and Bifrost family of GPUs. Currently, only the T860 and
> T760 Midgard GPUs have been tested.

FWIW, on an antique T624 (Juno) it seems to work no worse than the kbase 
driver plus panfrost-nondrm, which is to say it gets far enough to prove 
that the userspace definitely doesn't support T624 (kmscube manages to 
show a grey background, but the GPU is constantly falling over with page 
faults trying to dereference address 0 - for obvious reasons I'm not 
going to get any further involved in debugging that).

A couple of discoveries and general observations below.

> v2:
> - Add GPU reset on job hangs (Tomeu)
> - Add RuntimePM and devfreq support (Tomeu)
> - Fix T760 support (Tomeu)
> - Add a TODO file (Rob, Tomeu)
> - Support multiple in fences (Tomeu)
> - Drop support for shared fences (Tomeu)
> - Fill in MMU de-init (Rob)
> - Move register definitions back to single header (Rob)
> - Clean-up hardcoded job submit todos (Rob)
> - Implement feature setup based on features/issues (Rob)
> - Add remaining Midgard DT compatible strings (Rob)
> 
> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> Cc: Maxime Ripard <maxime.ripard@bootlin.com>
> Cc: Sean Paul <sean@poorly.run>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> Cc: Lyude Paul <lyude@redhat.com>
> Cc: Eric Anholt <eric@anholt.net>
> Signed-off-by: Marty E. Plummer <hanetzer@startmail.com>
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---
[...]
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c
> new file mode 100644
> index 000000000000..227ba5202a6f
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.c
> @@ -0,0 +1,227 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
> +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> +
> +#include <linux/clk.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include "panfrost_device.h"
> +#include "panfrost_devfreq.h"
> +#include "panfrost_features.h"
> +#include "panfrost_gpu.h"
> +#include "panfrost_job.h"
> +#include "panfrost_mmu.h"
> +
> +static int panfrost_clk_init(struct panfrost_device *pfdev)
> +{
> +	int err;
> +	unsigned long rate;
> +
> +	pfdev->clock = devm_clk_get(pfdev->dev, NULL);
> +	if (IS_ERR(pfdev->clock)) {

The DT binding says clocks are optional, but this doesn't treat them as 
such.

> +		dev_err(pfdev->dev, "get clock failed %ld\n", PTR_ERR(pfdev->clock));
> +		return PTR_ERR(pfdev->clock);
> +	}
> +
> +	rate = clk_get_rate(pfdev->clock);
> +	dev_info(pfdev->dev, "clock rate = %lu\n", rate);
> +
> +	err = clk_prepare_enable(pfdev->clock);
> +	if (err)
> +		return err;
> +
> +	return 0;
> +}
[...]
> diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c
> new file mode 100644
> index 000000000000..57a99032bcc6
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
[...]
> +static int panfrost_probe(struct platform_device *pdev)
> +{
> +	struct panfrost_device *pfdev;
> +	struct drm_device *ddev;
> +	int err;
> +
> +	pfdev = devm_kzalloc(&pdev->dev, sizeof(*pfdev), GFP_KERNEL);
> +	if (!pfdev)
> +		return -ENOMEM;
> +
> +	pfdev->pdev = pdev;
> +	pfdev->dev = &pdev->dev;
> +
> +	platform_set_drvdata(pdev, pfdev);
> +
> +	/* Allocate and initialze the DRM device. */
> +	ddev = drm_dev_alloc(&panfrost_drm_driver, &pdev->dev);
> +	if (IS_ERR(ddev))
> +		return PTR_ERR(ddev);
> +
> +	ddev->dev_private = pfdev;
> +	pfdev->ddev = ddev;
> +
> +	spin_lock_init(&pfdev->mm_lock);
> +
> +	/* 4G enough for now. can be 48-bit */
> +	drm_mm_init(&pfdev->mm, SZ_32M >> PAGE_SHIFT, SZ_4G);

You probably want a dma_set_mask_and_coherent() call for your 'real' 
output address size somewhere - the default 32-bit mask works out OK for 
RK3399, but on systems with RAM above 4GB io-pgtable will get very 
unhappy about DMA bounce-buffering.

> +
> +	pm_runtime_use_autosuspend(pfdev->dev);
> +	pm_runtime_set_autosuspend_delay(pfdev->dev, 50); /* ~3 frames */
> +	pm_runtime_enable(pfdev->dev);
> +
> +	err = panfrost_device_init(pfdev);
> +	if (err) {
> +		dev_err(&pdev->dev, "Fatal error during GPU init\n");
> +		goto err_out0;
> +	}
> +
> +	err = panfrost_devfreq_init(pfdev);
> +	if (err) {
> +		dev_err(&pdev->dev, "Fatal error during devfreq init\n");
> +		goto err_out1;
> +	}
> +
> +	/*
> +	 * Register the DRM device with the core and the connectors with
> +	 * sysfs
> +	 */
> +	err = drm_dev_register(ddev, 0);
> +	if (err < 0)
> +		goto err_out1;
> +
> +	return 0;
> +
> +err_out1:
> +	panfrost_device_fini(pfdev);
> +err_out0:
> +	drm_dev_put(ddev);

Reloading the module after a failed probe complains about an unbalanced 
pm_runtime_enable(), so I guess you need a disable somewhere around here.

> +	return err;
> +}
> +
> +static int panfrost_remove(struct platform_device *pdev)
> +{
> +	struct panfrost_device *pfdev = platform_get_drvdata(pdev);
> +	struct drm_device *ddev = pfdev->ddev;
> +
> +	drm_dev_unregister(ddev);
> +	pm_runtime_get_sync(pfdev->dev);
> +	pm_runtime_put_sync_autosuspend(pfdev->dev);
> +	pm_runtime_disable(pfdev->dev);
> +	panfrost_device_fini(pfdev);
> +	drm_dev_put(ddev);
> +	return 0;
> +}
> +
> +static const struct of_device_id dt_match[] = {
> +	{ .compatible = "arm,mali-t604" },
> +	{ .compatible = "arm,mali-t624" },
> +	{ .compatible = "arm,mali-t628" },
> +	{ .compatible = "arm,mali-t720" },
> +	{ .compatible = "arm,mali-t760" },
> +	{ .compatible = "arm,mali-t820" },
> +	{ .compatible = "arm,mali-t830" },
> +	{ .compatible = "arm,mali-t860" },
> +	{ .compatible = "arm,mali-t880" },

Any chance of resurrecting the generic "arm,mali-midgard" compatible? :P

> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, dt_match);
> +
> +static const struct dev_pm_ops panfrost_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
> +	SET_RUNTIME_PM_OPS(panfrost_device_suspend, panfrost_device_resume, NULL)
> +};
> +
> +static struct platform_driver panfrost_driver = {
> +	.probe		= panfrost_probe,
> +	.remove		= panfrost_remove,
> +	.driver		= {
> +		.name	= "panfrost",
> +		.pm	= &panfrost_pm_ops,
> +		.of_match_table = dt_match,
> +	},
> +};
> +module_platform_driver(panfrost_driver);
> +
> +MODULE_AUTHOR("Panfrost Project Developers");
> +MODULE_DESCRIPTION("Panfrost DRM Driver");
> +MODULE_LICENSE("GPL v2");
[...]
> diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.c b/drivers/gpu/drm/panfrost/panfrost_gpu.c
> new file mode 100644
> index 000000000000..867e2ba3a761
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_gpu.c
[...]
> +static void panfrost_gpu_init_quirks(struct panfrost_device *pfdev)
> +{
> +	u32 quirks = 0;
> +
> +	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_8443) ||
> +	    panfrost_has_hw_issue(pfdev, HW_ISSUE_11035))
> +		quirks |= SC_LS_PAUSEBUFFER_DISABLE;
> +
> +	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_10327))
> +		quirks |= SC_SDC_DISABLE_OQ_DISCARD;
> +
> +	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_10797))
> +		quirks |= SC_ENABLE_TEXGRD_FLAGS;
> +
> +	if (!panfrost_has_hw_issue(pfdev, GPUCORE_1619)) {
> +		if (panfrost_model_cmp(pfdev, 0x750) < 0) /* T60x, T62x, T72x */
> +			quirks |= SC_LS_ATTR_CHECK_DISABLE;
> +		else if (panfrost_model_cmp(pfdev, 0x880) <= 0) /* T76x, T8xx */
> +			quirks |= SC_LS_ALLOW_ATTR_TYPES;
> +	}
> +
> +	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_TLS_HASHING))
> +		quirks |= SC_TLS_HASH_ENABLE;
> +
> +	if (quirks)
> +		gpu_write(pfdev, GPU_SHADER_CONFIG, quirks);
> +
> +
> +	quirks = gpu_read(pfdev, GPU_TILER_CONFIG);
> +
> +	/* Set tiler clock gate override if required */
> +	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_T76X_3953))
> +		quirks |= TC_CLOCK_GATE_OVERRIDE;
> +
> +	gpu_write(pfdev, GPU_TILER_CONFIG, quirks);
> +
> +
> +	quirks = gpu_read(pfdev, GPU_L2_MMU_CONFIG);
> +
> +	/* Limit read & write ID width for AXI */
> +	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG))
> +		quirks &= ~(L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_READS |
> +			    L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_WRITES);
> +	else
> +		quirks &= ~(L2_MMU_CONFIG_LIMIT_EXTERNAL_READS |
> +			    L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES);
> +
> +#if 0
> +	if (kbdev->system_coherency == COHERENCY_ACE) {
> +		/* Allow memory configuration disparity to be ignored, we
> +		 * optimize the use of shared memory and thus we expect
> +		 * some disparity in the memory configuration */
> +		quirks |= L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY;

Well that sounds terrifying; I rather wish my brain had preprocessed 
that #if already.

> +	}
> +#endif
> +	gpu_write(pfdev, GPU_L2_MMU_CONFIG, quirks);
> +
> +	quirks = 0;
> +	if ((panfrost_model_eq(pfdev, 0x860) || panfrost_model_eq(pfdev, 0x880)) &&
> +	    pfdev->features.revision >= 0x2000)
> +		quirks |= JM_MAX_JOB_THROTTLE_LIMIT << JM_JOB_THROTTLE_LIMIT_SHIFT;
> +	else if (panfrost_model_eq(pfdev, 0x6000) &&
> +		 pfdev->features.coherency_features == COHERENCY_ACE)
> +		quirks |= (COHERENCY_ACE_LITE | COHERENCY_ACE) <<
> +			   JM_FORCE_COHERENCY_FEATURES_SHIFT;

Experience says you can never really trust what ID registers claim about 
system integration stuff like coherency, because eventually someone will 
get a tieoff wrong and make it all fall apart. If even the vendor driver 
has a DT override for it you know you're on thin ice ;)

Ultimately, most of your I/O coherency behaviour will be governed by 
what the DMA API thinks (based on "dma-coherent"), so if you end up with 
mismatched expectations at the point coherency_features gets set up then 
you're liable to have a bad time. See the arm-smmu drivers for prior 
examples of handling the equivalent thing.

Robin.

> +
> +	if (quirks)
> +		gpu_write(pfdev, GPU_JM_CONFIG, quirks);
> +}
On 01/04/2019 09:24, Neil Armstrong wrote:
> On 01/04/2019 09:47, Rob Herring wrote:
>> This adds the initial driver for panfrost which supports Arm Mali
>> Midgard and Bifrost family of GPUs. Currently, only the T860 and
>> T760 Midgard GPUs have been tested.
>>
>> v2:
>> - Add GPU reset on job hangs (Tomeu)
>> - Add RuntimePM and devfreq support (Tomeu)
>> - Fix T760 support (Tomeu)
>> - Add a TODO file (Rob, Tomeu)
>> - Support multiple in fences (Tomeu)
>> - Drop support for shared fences (Tomeu)
>> - Fill in MMU de-init (Rob)
>> - Move register definitions back to single header (Rob)
>> - Clean-up hardcoded job submit todos (Rob)
>> - Implement feature setup based on features/issues (Rob)
>> - Add remaining Midgard DT compatible strings (Rob)
>>
>> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
>> Cc: Maxime Ripard <maxime.ripard@bootlin.com>
>> Cc: Sean Paul <sean@poorly.run>
>> Cc: David Airlie <airlied@linux.ie>
>> Cc: Daniel Vetter <daniel@ffwll.ch>
>> Cc: Alyssa Rosenzweig <alyssa@rosenzweig.io>
>> Cc: Lyude Paul <lyude@redhat.com>
>> Cc: Eric Anholt <eric@anholt.net>
>> Signed-off-by: Marty E. Plummer <hanetzer@startmail.com>
>> Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
>> Signed-off-by: Rob Herring <robh@kernel.org>
>> ---
>> Neil, I've kept your reset support separate for now. Let me know if you
>> prefer me to squash it or keep it separate.
> 
> You can squash all my changes and add my sign-off.

FWIW, looking at Rob's branch there's a little bug in panfrost_reset_init():

+	if (IS_ERR(pfdev->rstc)) {
+		dev_err(pfdev->dev, "get reset failed %ld\n", PTR_ERR(pfdev->clock));

Looks like that "pfdev->clock" should be "pfdev->rstc".

Robin.
> the userspace definitely doesn't support T624

This is true, yes. Shouldn't be too hard to backport; if there's still
interest in Midgard 1st/2nd gen, I suppose I can grab hardware and sort
it out...

> You probably want a dma_set_mask_and_coherent() call for your 'real' output
> address size somewhere - the default 32-bit mask works out OK for RK3399,
> but on systems with RAM above 4GB io-pgtable will get very unhappy about DMA
> bounce-buffering.

Out of curiosity, are there Mali systems with >4GB RAM? That sounds
awesome :)

> Any chance of resurrecting the generic "arm,mali-midgard" compatible? :P

...Would that require editing everybody's DT file?

-----

Thank you for the review!
On 02/04/2019 01:33, Alyssa Rosenzweig wrote:
>> the userspace definitely doesn't support T624
> 
> This is true, yes. Shouldn't be too hard to backport; if there's still
> interest in Midgard 1st/2nd gen, I suppose I can grab hardware and sort
> it out...

I'm quite likely the only person trying this on an Arm Juno board, and 
even then it's really only for giggles because I can :)  I guess there 
might be a fair few Odroid-XU3/XU4 (T628) users interested, though.

>> You probably want a dma_set_mask_and_coherent() call for your 'real' output
>> address size somewhere - the default 32-bit mask works out OK for RK3399,
>> but on systems with RAM above 4GB io-pgtable will get very unhappy about DMA
>> bounce-buffering.
> 
> Out of curiosity, are there Mali systems with >4GB RAM? That sounds
> awesome :)

Now that the "early-access Armv8 silicon" angle has well and truly 
expired, Juno is essentially a prototyping platform where the SoC just 
serves to (slowly) drive interesting things in FPGA cards, so although 
it may have 8GB of RAM, it's not all that exciting. There is one 
somewhat more realistic board I'm aware of, namely HiKey 970 with a G72 
and 6GB.

>> Any chance of resurrecting the generic "arm,mali-midgard" compatible? :P
> 
> ...Would that require editing everybody's DT file?

If they already have one of the strings from the current upstream 
binding, no - I only mean to suggest adding it as an additional 
last-level fallback. That would aid compatibility with downstream DTs, 
for example RK3288 which currently has zero overlap:

upstream: "rockchip,rk3288-mali", "arm,mali-t760";

downstream: "arm,malit764", "arm,malit76x", "arm,malit7xx", 
"arm,mali-midgard";

Similarly, it might be reasonable for panfrost_{gpu,mmu,job}_init() to 
retry platform_get_irq_byname() with uppercase interrupt names if the 
expected ones aren't found - obviously the upstream binding comes first 
and foremost, but I don't see any harm in quietly supporting bits of the 
downstream binding if it makes users' lives easier when switching 
between mainline and vendor kernels.

Cheers,
Robin.
On Mon, Apr 1, 2019 at 2:12 PM Robin Murphy <robin.murphy@arm.com> wrote:
>
> On 01/04/2019 08:47, Rob Herring wrote:
> > This adds the initial driver for panfrost which supports Arm Mali
> > Midgard and Bifrost family of GPUs. Currently, only the T860 and
> > T760 Midgard GPUs have been tested.
>
> FWIW, on an antique T624 (Juno) it seems to work no worse than the kbase
> driver plus panfrost-nondrm, which is to say it gets far enough to prove
> that the userspace definitely doesn't support T624 (kmscube manages to
> show a grey background, but the GPU is constantly falling over with page
> faults trying to dereference address 0 - for obvious reasons I'm not
> going to get any further involved in debugging that).
>
> A couple of discoveries and general observations below.
>
> > v2:
> > - Add GPU reset on job hangs (Tomeu)
> > - Add RuntimePM and devfreq support (Tomeu)
> > - Fix T760 support (Tomeu)
> > - Add a TODO file (Rob, Tomeu)
> > - Support multiple in fences (Tomeu)
> > - Drop support for shared fences (Tomeu)
> > - Fill in MMU de-init (Rob)
> > - Move register definitions back to single header (Rob)
> > - Clean-up hardcoded job submit todos (Rob)
> > - Implement feature setup based on features/issues (Rob)
> > - Add remaining Midgard DT compatible strings (Rob)
> >
> > Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> > Cc: Maxime Ripard <maxime.ripard@bootlin.com>
> > Cc: Sean Paul <sean@poorly.run>
> > Cc: David Airlie <airlied@linux.ie>
> > Cc: Daniel Vetter <daniel@ffwll.ch>
> > Cc: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> > Cc: Lyude Paul <lyude@redhat.com>
> > Cc: Eric Anholt <eric@anholt.net>
> > Signed-off-by: Marty E. Plummer <hanetzer@startmail.com>
> > Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> > Signed-off-by: Rob Herring <robh@kernel.org>
> > ---
> [...]
> > diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c
> > new file mode 100644
> > index 000000000000..227ba5202a6f
> > --- /dev/null
> > +++ b/drivers/gpu/drm/panfrost/panfrost_device.c
> > @@ -0,0 +1,227 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
> > +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> > +
> > +#include <linux/clk.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/regulator/consumer.h>
> > +
> > +#include "panfrost_device.h"
> > +#include "panfrost_devfreq.h"
> > +#include "panfrost_features.h"
> > +#include "panfrost_gpu.h"
> > +#include "panfrost_job.h"
> > +#include "panfrost_mmu.h"
> > +
> > +static int panfrost_clk_init(struct panfrost_device *pfdev)
> > +{
> > +     int err;
> > +     unsigned long rate;
> > +
> > +     pfdev->clock = devm_clk_get(pfdev->dev, NULL);
> > +     if (IS_ERR(pfdev->clock)) {
>
> The DT binding says clocks are optional, but this doesn't treat them as
> such.

Hum, I would think effectively clocks are always there and necessary
for thermal reasons.


> > +     spin_lock_init(&pfdev->mm_lock);
> > +
> > +     /* 4G enough for now. can be 48-bit */
> > +     drm_mm_init(&pfdev->mm, SZ_32M >> PAGE_SHIFT, SZ_4G);
>
> You probably want a dma_set_mask_and_coherent() call for your 'real'
> output address size somewhere - the default 32-bit mask works out OK for
> RK3399, but on systems with RAM above 4GB io-pgtable will get very
> unhappy about DMA bounce-buffering.

Yes, I have a todo for figuring out the # of physaddr bits in the mmu
setup (as this call is just relevant to the input address side).
Though maybe just calling dma_set_mask_and_coherent() is enough and I
don't need to know the exact number of output bits for the io-pgtable
setup?

> > +     return err;
> > +}
> > +
> > +static int panfrost_remove(struct platform_device *pdev)
> > +{
> > +     struct panfrost_device *pfdev = platform_get_drvdata(pdev);
> > +     struct drm_device *ddev = pfdev->ddev;
> > +
> > +     drm_dev_unregister(ddev);
> > +     pm_runtime_get_sync(pfdev->dev);
> > +     pm_runtime_put_sync_autosuspend(pfdev->dev);
> > +     pm_runtime_disable(pfdev->dev);
> > +     panfrost_device_fini(pfdev);
> > +     drm_dev_put(ddev);
> > +     return 0;
> > +}
> > +
> > +static const struct of_device_id dt_match[] = {
> > +     { .compatible = "arm,mali-t604" },
> > +     { .compatible = "arm,mali-t624" },
> > +     { .compatible = "arm,mali-t628" },
> > +     { .compatible = "arm,mali-t720" },
> > +     { .compatible = "arm,mali-t760" },
> > +     { .compatible = "arm,mali-t820" },
> > +     { .compatible = "arm,mali-t830" },
> > +     { .compatible = "arm,mali-t860" },
> > +     { .compatible = "arm,mali-t880" },
>
> Any chance of resurrecting the generic "arm,mali-midgard" compatible? :P

I wouldn't mind, but we still need all these and I don't think we'd be
adding more. For bifrost, we're adding 'arm,mali-bifrost' from the
start.

> > diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.c b/drivers/gpu/drm/panfrost/panfrost_gpu.c
> > new file mode 100644
> > index 000000000000..867e2ba3a761
> > --- /dev/null
> > +++ b/drivers/gpu/drm/panfrost/panfrost_gpu.c
> [...]

> > +     /* Limit read & write ID width for AXI */
> > +     if (panfrost_has_hw_feature(pfdev, HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG))
> > +             quirks &= ~(L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_READS |
> > +                         L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_WRITES);
> > +     else
> > +             quirks &= ~(L2_MMU_CONFIG_LIMIT_EXTERNAL_READS |
> > +                         L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES);
> > +
> > +#if 0
> > +     if (kbdev->system_coherency == COHERENCY_ACE) {
> > +             /* Allow memory configuration disparity to be ignored, we
> > +              * optimize the use of shared memory and thus we expect
> > +              * some disparity in the memory configuration */
> > +             quirks |= L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY;
>
> Well that sounds terrifying; I rather wish my brain had preprocessed
> that #if already.

What can I say, copied from Arm's driver. I'm just going to drop for now.

>
> > +     }
> > +#endif
> > +     gpu_write(pfdev, GPU_L2_MMU_CONFIG, quirks);
> > +
> > +     quirks = 0;
> > +     if ((panfrost_model_eq(pfdev, 0x860) || panfrost_model_eq(pfdev, 0x880)) &&
> > +         pfdev->features.revision >= 0x2000)
> > +             quirks |= JM_MAX_JOB_THROTTLE_LIMIT << JM_JOB_THROTTLE_LIMIT_SHIFT;
> > +     else if (panfrost_model_eq(pfdev, 0x6000) &&
> > +              pfdev->features.coherency_features == COHERENCY_ACE)
> > +             quirks |= (COHERENCY_ACE_LITE | COHERENCY_ACE) <<
> > +                        JM_FORCE_COHERENCY_FEATURES_SHIFT;
>
> Experience says you can never really trust what ID registers claim about
> system integration stuff like coherency, because eventually someone will
> get a tieoff wrong and make it all fall apart. If even the vendor driver
> has a DT override for it you know you're on thin ice ;)

Unlike the vendor driver, we only have to care about cases seen upstream...

> Ultimately, most of your I/O coherency behaviour will be governed by
> what the DMA API thinks (based on "dma-coherent"), so if you end up with
> mismatched expectations at the point coherency_features gets set up then
> you're liable to have a bad time. See the arm-smmu drivers for prior
> examples of handling the equivalent thing.

None of this matters til bifrost and a platform implementing this, so
I'll worry about it then.

Thanks for the review.

Rob
On 01/04/2019 08:47, Rob Herring wrote:
> This adds the initial driver for panfrost which supports Arm Mali
> Midgard and Bifrost family of GPUs. Currently, only the T860 and
> T760 Midgard GPUs have been tested.
> 
> v2:
> - Add GPU reset on job hangs (Tomeu)
> - Add RuntimePM and devfreq support (Tomeu)
> - Fix T760 support (Tomeu)
> - Add a TODO file (Rob, Tomeu)
> - Support multiple in fences (Tomeu)
> - Drop support for shared fences (Tomeu)
> - Fill in MMU de-init (Rob)
> - Move register definitions back to single header (Rob)
> - Clean-up hardcoded job submit todos (Rob)
> - Implement feature setup based on features/issues (Rob)
> - Add remaining Midgard DT compatible strings (Rob)
> 
> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> Cc: Maxime Ripard <maxime.ripard@bootlin.com>
> Cc: Sean Paul <sean@poorly.run>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: Alyssa Rosenzweig <alyssa@rosenzweig.io>
> Cc: Lyude Paul <lyude@redhat.com>
> Cc: Eric Anholt <eric@anholt.net>
> Signed-off-by: Marty E. Plummer <hanetzer@startmail.com>
> Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---
> Neil, I've kept your reset support separate for now. Let me know if you
> prefer me to squash it or keep it separate.
> 
>  drivers/gpu/drm/Kconfig                      |   2 +
>  drivers/gpu/drm/Makefile                     |   1 +
>  drivers/gpu/drm/panfrost/Kconfig             |  14 +
>  drivers/gpu/drm/panfrost/Makefile            |  12 +
>  drivers/gpu/drm/panfrost/TODO                |  27 +
>  drivers/gpu/drm/panfrost/panfrost_devfreq.c  | 191 +++++++
>  drivers/gpu/drm/panfrost/panfrost_devfreq.h  |  14 +
>  drivers/gpu/drm/panfrost/panfrost_device.c   | 227 ++++++++
>  drivers/gpu/drm/panfrost/panfrost_device.h   | 118 ++++
>  drivers/gpu/drm/panfrost/panfrost_drv.c      | 484 ++++++++++++++++
>  drivers/gpu/drm/panfrost/panfrost_features.h | 309 +++++++++++
>  drivers/gpu/drm/panfrost/panfrost_gem.c      |  92 +++
>  drivers/gpu/drm/panfrost/panfrost_gem.h      |  29 +
>  drivers/gpu/drm/panfrost/panfrost_gpu.c      | 374 +++++++++++++
>  drivers/gpu/drm/panfrost/panfrost_gpu.h      |  19 +
>  drivers/gpu/drm/panfrost/panfrost_issues.h   | 176 ++++++
>  drivers/gpu/drm/panfrost/panfrost_job.c      | 556 +++++++++++++++++++
>  drivers/gpu/drm/panfrost/panfrost_job.h      |  51 ++
>  drivers/gpu/drm/panfrost/panfrost_mmu.c      | 366 ++++++++++++
>  drivers/gpu/drm/panfrost/panfrost_mmu.h      |  17 +
>  drivers/gpu/drm/panfrost/panfrost_regs.h     | 298 ++++++++++
>  include/uapi/drm/panfrost_drm.h              | 140 +++++
>  22 files changed, 3517 insertions(+)
>  create mode 100644 drivers/gpu/drm/panfrost/Kconfig
>  create mode 100644 drivers/gpu/drm/panfrost/Makefile
>  create mode 100644 drivers/gpu/drm/panfrost/TODO
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_devfreq.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_devfreq.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_device.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_device.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_drv.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_features.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_gem.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_gem.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_gpu.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_gpu.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_issues.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_job.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_job.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_mmu.c
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_mmu.h
>  create mode 100644 drivers/gpu/drm/panfrost/panfrost_regs.h
>  create mode 100644 include/uapi/drm/panfrost_drm.h
> 
> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
> index 5e1bc630b885..927cae2468c3 100644
> --- a/drivers/gpu/drm/Kconfig
> +++ b/drivers/gpu/drm/Kconfig
> @@ -337,6 +337,8 @@ source "drivers/gpu/drm/xen/Kconfig"
> 
>  source "drivers/gpu/drm/vboxvideo/Kconfig"
> 
> +source "drivers/gpu/drm/panfrost/Kconfig"
> +
>  # Keep legacy drivers last
> 
>  menuconfig DRM_LEGACY
> diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
> index e630eccb951c..e1255571762d 100644
> --- a/drivers/gpu/drm/Makefile
> +++ b/drivers/gpu/drm/Makefile
> @@ -111,3 +111,4 @@ obj-$(CONFIG_DRM_PL111) += pl111/
>  obj-$(CONFIG_DRM_TVE200) += tve200/
>  obj-$(CONFIG_DRM_XEN) += xen/
>  obj-$(CONFIG_DRM_VBOXVIDEO) += vboxvideo/
> +obj-$(CONFIG_DRM_PANFROST) += panfrost/
> diff --git a/drivers/gpu/drm/panfrost/Kconfig b/drivers/gpu/drm/panfrost/Kconfig
> new file mode 100644
> index 000000000000..7f5e572daa2d
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/Kconfig
> @@ -0,0 +1,14 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +config DRM_PANFROST
> +	tristate "Panfrost (DRM support for ARM Mali Midgard/Bifrost GPUs)"
> +	depends on DRM
> +	depends on ARM || ARM64 || COMPILE_TEST
> +	depends on MMU
> +	select DRM_SCHED
> +	select IOMMU_SUPPORT
> +	select IOMMU_IO_PGTABLE_LPAE
> +	select DRM_GEM_SHMEM_HELPER
> +	help
> +	  DRM driver for ARM Mali Midgard (T6xx, T7xx, T8xx) and
> +	  Bifrost (G3x, G5x, G7x) GPUs.
> diff --git a/drivers/gpu/drm/panfrost/Makefile b/drivers/gpu/drm/panfrost/Makefile
> new file mode 100644
> index 000000000000..6de72d13c58f
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/Makefile
> @@ -0,0 +1,12 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +panfrost-y := \
> +	panfrost_drv.o \
> +	panfrost_device.o \
> +	panfrost_devfreq.o \
> +	panfrost_gem.o \
> +	panfrost_gpu.o \
> +	panfrost_job.o \
> +	panfrost_mmu.o
> +
> +obj-$(CONFIG_DRM_PANFROST) += panfrost.o
> diff --git a/drivers/gpu/drm/panfrost/TODO b/drivers/gpu/drm/panfrost/TODO
> new file mode 100644
> index 000000000000..c2e44add37d8
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/TODO
> @@ -0,0 +1,27 @@
> +- Thermal support.
> +
> +- Bifrost support:
> +  - DT bindings (Neil, WIP)
> +  - MMU page table format and address space setup
> +  - Bifrost specific feature and issue handling
> +  - Coherent DMA support
> +
> +- Support for 2MB pages. The io-pgtable code already supports this. Finishing
> +  support involves either copying or adapting the iommu API to handle passing
> +  aligned addresses and sizes to the io-pgtable code.
> +
> +- Per FD address space support. The h/w supports multiple addresses spaces.
> +  The hard part is handling when more address spaces are needed than what
> +  the h/w provides.
> +
> +- Support pinning pages on demand (GPU page faults).
> +
> +- Support userspace controlled GPU virtual addresses. Needed for Vulkan. (Tomeu)
> +
> +- Support for madvise and a shrinker.
> +
> +- Compute job support. So called 'compute only' jobs need to be plumbed up to
> +  userspace.
> +
> +- Performance counter support. (Boris)
> +
> diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> new file mode 100644
> index 000000000000..b1c4453f9991
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
> @@ -0,0 +1,191 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright 2019 Collabora ltd. */
> +#include <linux/devfreq.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_opp.h>
> +#include <linux/clk.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include "panfrost_device.h"
> +#include "panfrost_features.h"
> +#include "panfrost_issues.h"
> +#include "panfrost_gpu.h"
> +#include "panfrost_regs.h"
> +
> +static int panfrost_devfreq_target(struct device *dev, unsigned long *freq,
> +				   u32 flags)
> +{
> +	struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
> +	struct dev_pm_opp *opp;
> +	unsigned long old_clk_rate = pfdev->devfreq.cur_freq;
> +	unsigned long target_volt, target_rate;
> +	int err;
> +
> +	opp = devfreq_recommended_opp(dev, freq, flags);
> +	if (IS_ERR(opp))
> +		return PTR_ERR(opp);
> +
> +	target_rate = dev_pm_opp_get_freq(opp);
> +	target_volt = dev_pm_opp_get_voltage(opp);
> +	dev_pm_opp_put(opp);
> +
> +	if (old_clk_rate == target_rate)
> +		return 0;
> +
> +	/*
> +	 * If frequency scaling from low to high, adjust voltage first.
> +	 * If frequency scaling from high to low, adjust frequency first.
> +	 */
> +	if (old_clk_rate < target_rate) {
> +		err = regulator_set_voltage(pfdev->regulator, target_volt,
> +					    target_volt);
> +		if (err) {
> +			dev_err(dev, "Cannot set voltage %lu uV\n",
> +				target_volt);
> +			return err;
> +		}
> +	}
> +
> +	err = clk_set_rate(pfdev->clock, target_rate);
> +	if (err) {
> +		dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
> +			err);
> +		regulator_set_voltage(pfdev->regulator, pfdev->devfreq.cur_volt,
> +				      pfdev->devfreq.cur_volt);
> +		return err;
> +	}
> +
> +	if (old_clk_rate > target_rate) {
> +		err = regulator_set_voltage(pfdev->regulator, target_volt,
> +					    target_volt);
> +		if (err)
> +			dev_err(dev, "Cannot set voltage %lu uV\n", target_volt);
> +	}
> +
> +	pfdev->devfreq.cur_freq = target_rate;
> +	pfdev->devfreq.cur_volt = target_volt;
> +
> +	return 0;
> +}
> +
> +static void panfrost_devfreq_reset(struct panfrost_device *pfdev)
> +{
> +	ktime_t now = ktime_get();
> +	int i;
> +
> +	for (i = 0; i < NUM_JOB_SLOTS; i++) {
> +		pfdev->devfreq.busy_time[i] = 0;
> +		pfdev->devfreq.idle_time[i] = 0;
> +		pfdev->devfreq.time_last_update[i] = now;
> +	}
> +}
> +
> +static int panfrost_devfreq_get_dev_status(struct device *dev,
> +					   struct devfreq_dev_status *status)
> +{
> +	struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
> +	int i;
> +
> +	status->current_frequency = clk_get_rate(pfdev->clock);
> +	status->total_time = ktime_to_ns(ktime_add(pfdev->devfreq.busy_time[0],
> +						   pfdev->devfreq.idle_time[0]));
> +
> +	status->busy_time = 0;
> +	for (i = 0; i < NUM_JOB_SLOTS; i++) {
> +		status->busy_time += ktime_to_ns(pfdev->devfreq.busy_time[i]);
> +	}
> +
> +	/* We're scheduling only to one core atm, so don't divide for now */
> +	//status->busy_time /= NUM_JOB_SLOTS;
> +
> +	panfrost_devfreq_reset(pfdev);
> +
> +	dev_dbg(pfdev->dev, "busy %lu total %lu %lu %%\n", status->busy_time,
> +		status->total_time,
> +		status->busy_time * 100 / status->total_time);
> +
> +	return 0;
> +}
> +
> +static int panfrost_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
> +{
> +	struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
> +
> +	*freq = pfdev->devfreq.cur_freq;
> +
> +	return 0;
> +}
> +
> +static struct devfreq_dev_profile panfrost_devfreq_profile = {
> +	.polling_ms = 10,
> +	.target = panfrost_devfreq_target,
> +	.get_dev_status = panfrost_devfreq_get_dev_status,
> +	.get_cur_freq = panfrost_devfreq_get_cur_freq,
> +};
> +
> +int panfrost_devfreq_init(struct panfrost_device *pfdev)
> +{
> +	int ret;
> +	struct dev_pm_opp *opp;
> +
> +	ret = dev_pm_opp_of_add_table(&pfdev->pdev->dev);
> +	if (ret == -ENODEV) /* Optional, continue without devfreq */
> +		return 0;
> +
> +	panfrost_devfreq_reset(pfdev);
> +
> +	pfdev->devfreq.cur_freq = clk_get_rate(pfdev->clock);
> +
> +	opp = devfreq_recommended_opp(&pfdev->pdev->dev, &pfdev->devfreq.cur_freq, 0);
> +	if (IS_ERR(opp))
> +		return PTR_ERR(opp);
> +
> +	panfrost_devfreq_profile.initial_freq = pfdev->devfreq.cur_freq;
> +	dev_pm_opp_put(opp);
> +
> +	pfdev->devfreq.devfreq = devm_devfreq_add_device(&pfdev->pdev->dev,
> +			&panfrost_devfreq_profile, "simple_ondemand", NULL);
> +	if (IS_ERR(pfdev->devfreq.devfreq)) {
> +		DRM_DEV_ERROR(&pfdev->pdev->dev, "Couldn't initialize GPU devfreq\n");
> +		pfdev->devfreq.devfreq = NULL;
> +		return PTR_ERR(pfdev->devfreq.devfreq);
> +	}
> +
> +	return 0;
> +}
> +
> +void panfrost_devfreq_resume(struct panfrost_device *pfdev)
> +{
> +	if (!pfdev->devfreq.devfreq)
> +		return;
> +
> +	panfrost_devfreq_reset(pfdev);
> +	devfreq_resume_device(pfdev->devfreq.devfreq);
> +}
> +
> +void panfrost_devfreq_suspend(struct panfrost_device *pfdev)
> +{
> +	if (!pfdev->devfreq.devfreq)
> +		return;
> +
> +	devfreq_suspend_device(pfdev->devfreq.devfreq);
> +}
> +
> +void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev, int slot, bool busy)
> +{
> +	ktime_t now;
> +	ktime_t last;
> +
> +	if (!pfdev->devfreq.devfreq)
> +		return;
> +
> +	now = ktime_get();
> +	last = pfdev->devfreq.time_last_update[slot];
> +
> +	if (busy)
> +		pfdev->devfreq.busy_time[slot] += ktime_sub(now, last);
> +	else
> +		pfdev->devfreq.idle_time[slot] += ktime_sub(now, last);
> +
> +	pfdev->devfreq.time_last_update[slot] = now;
> +}
> diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.h b/drivers/gpu/drm/panfrost/panfrost_devfreq.h
> new file mode 100644
> index 000000000000..1dd7db3b8630
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.h
> @@ -0,0 +1,14 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright 2019 Collabora ltd. */
> +
> +#ifndef __PANFROST_DEVFREQ_H__
> +#define __PANFROST_DEVFREQ_H__
> +
> +int panfrost_devfreq_init(struct panfrost_device *pfdev);
> +
> +void panfrost_devfreq_resume(struct panfrost_device *pfdev);
> +void panfrost_devfreq_suspend(struct panfrost_device *pfdev);
> +
> +void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev, int slot, bool busy);
> +
> +#endif /* __PANFROST_DEVFREQ_H__ */
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c
> new file mode 100644
> index 000000000000..227ba5202a6f
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.c
> @@ -0,0 +1,227 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
> +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> +
> +#include <linux/clk.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include "panfrost_device.h"
> +#include "panfrost_devfreq.h"
> +#include "panfrost_features.h"
> +#include "panfrost_gpu.h"
> +#include "panfrost_job.h"
> +#include "panfrost_mmu.h"
> +
> +static int panfrost_clk_init(struct panfrost_device *pfdev)
> +{
> +	int err;
> +	unsigned long rate;
> +
> +	pfdev->clock = devm_clk_get(pfdev->dev, NULL);
> +	if (IS_ERR(pfdev->clock)) {
> +		dev_err(pfdev->dev, "get clock failed %ld\n", PTR_ERR(pfdev->clock));
> +		return PTR_ERR(pfdev->clock);
> +	}
> +
> +	rate = clk_get_rate(pfdev->clock);
> +	dev_info(pfdev->dev, "clock rate = %lu\n", rate);
> +
> +	err = clk_prepare_enable(pfdev->clock);
> +	if (err)
> +		return err;
> +
> +	return 0;
> +}
> +
> +static void panfrost_clk_fini(struct panfrost_device *pfdev)
> +{
> +	clk_disable_unprepare(pfdev->clock);
> +}
> +
> +static int panfrost_regulator_init(struct panfrost_device *pfdev)
> +{
> +	int ret;
> +
> +	pfdev->regulator = devm_regulator_get_optional(pfdev->dev, "mali");
> +	if (IS_ERR(pfdev->regulator)) {
> +		ret = PTR_ERR(pfdev->regulator);
> +		pfdev->regulator = NULL;
> +		if (ret == -ENODEV)
> +			return 0;
> +		dev_err(pfdev->dev, "failed to get regulator: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = regulator_enable(pfdev->regulator);
> +	if (ret < 0) {
> +		dev_err(pfdev->dev, "failed to enable regulator: %d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void panfrost_regulator_fini(struct panfrost_device *pfdev)
> +{
> +	if (pfdev->regulator)
> +		regulator_disable(pfdev->regulator);
> +}
> +
> +int panfrost_device_init(struct panfrost_device *pfdev)
> +{
> +	int err;
> +	struct resource *res;
> +
> +	mutex_init(&pfdev->sched_lock);
> +	INIT_LIST_HEAD(&pfdev->scheduled_jobs);
> +
> +	spin_lock_init(&pfdev->hwaccess_lock);
> +
> +	err = panfrost_clk_init(pfdev);
> +	if (err) {
> +		dev_err(pfdev->dev, "clk init failed %d\n", err);
> +		return err;
> +	}
> +
> +	err = panfrost_regulator_init(pfdev);
> +	if (err) {
> +		dev_err(pfdev->dev, "regulator init failed %d\n", err);
> +		goto err_out0;
> +	}
> +
> +	res = platform_get_resource(pfdev->pdev, IORESOURCE_MEM, 0);
> +	pfdev->iomem = devm_ioremap_resource(pfdev->dev, res);
> +	if (IS_ERR(pfdev->iomem)) {
> +		dev_err(pfdev->dev, "failed to ioremap iomem\n");
> +		err = PTR_ERR(pfdev->iomem);
> +		goto err_out1;
> +	}
> +
> +	err = panfrost_gpu_init(pfdev);
> +	if (err)
> +		goto err_out1;
> +
> +	err = panfrost_mmu_init(pfdev);
> +	if (err)
> +		goto err_out2;
> +
> +	err = panfrost_job_init(pfdev);
> +	if (err)
> +		goto err_out3;
> +
> +	/* runtime PM will wake us up later */
> +	panfrost_gpu_power_off(pfdev);
> +
> +	pm_runtime_set_active(pfdev->dev);
> +	pm_runtime_get_sync(pfdev->dev);
> +	pm_runtime_mark_last_busy(pfdev->dev);
> +	pm_runtime_put_autosuspend(pfdev->dev);
> +
> +	return 0;
> +err_out3:
> +	panfrost_mmu_fini(pfdev);
> +err_out2:
> +	panfrost_gpu_fini(pfdev);
> +err_out1:
> +	panfrost_regulator_fini(pfdev);
> +err_out0:
> +	panfrost_clk_fini(pfdev);
> +	return err;
> +}
> +
> +void panfrost_device_fini(struct panfrost_device *pfdev)
> +{
> +	panfrost_regulator_fini(pfdev);
> +	panfrost_clk_fini(pfdev);
> +}
> +
> +const char *panfrost_exception_name(struct panfrost_device *pfdev, u32 exception_code)
> +{
> +	switch (exception_code) {
> +		/* Non-Fault Status code */
> +	case 0x00: return "NOT_STARTED/IDLE/OK";
> +	case 0x01: return "DONE";
> +	case 0x02: return "INTERRUPTED";
> +	case 0x03: return "STOPPED";
> +	case 0x04: return "TERMINATED";
> +	case 0x08: return "ACTIVE";
> +		/* Job exceptions */
> +	case 0x40: return "JOB_CONFIG_FAULT";
> +	case 0x41: return "JOB_POWER_FAULT";
> +	case 0x42: return "JOB_READ_FAULT";
> +	case 0x43: return "JOB_WRITE_FAULT";
> +	case 0x44: return "JOB_AFFINITY_FAULT";
> +	case 0x48: return "JOB_BUS_FAULT";
> +	case 0x50: return "INSTR_INVALID_PC";
> +	case 0x51: return "INSTR_INVALID_ENC";
> +	case 0x52: return "INSTR_TYPE_MISMATCH";
> +	case 0x53: return "INSTR_OPERAND_FAULT";
> +	case 0x54: return "INSTR_TLS_FAULT";
> +	case 0x55: return "INSTR_BARRIER_FAULT";
> +	case 0x56: return "INSTR_ALIGN_FAULT";
> +	case 0x58: return "DATA_INVALID_FAULT";
> +	case 0x59: return "TILE_RANGE_FAULT";
> +	case 0x5A: return "ADDR_RANGE_FAULT";
> +	case 0x60: return "OUT_OF_MEMORY";
> +		/* GPU exceptions */
> +	case 0x80: return "DELAYED_BUS_FAULT";
> +	case 0x88: return "SHAREABILITY_FAULT";
> +		/* MMU exceptions */
> +	case 0xC1: return "TRANSLATION_FAULT_LEVEL1";
> +	case 0xC2: return "TRANSLATION_FAULT_LEVEL2";
> +	case 0xC3: return "TRANSLATION_FAULT_LEVEL3";
> +	case 0xC4: return "TRANSLATION_FAULT_LEVEL4";
> +	case 0xC8: return "PERMISSION_FAULT";
> +	case 0xD1: return "TRANSTAB_BUS_FAULT_LEVEL1";
> +	case 0xD2: return "TRANSTAB_BUS_FAULT_LEVEL2";
> +	case 0xD3: return "TRANSTAB_BUS_FAULT_LEVEL3";
> +	case 0xD4: return "TRANSTAB_BUS_FAULT_LEVEL4";
> +	case 0xD8: return "ACCESS_FLAG";
> +	}
> +
> +	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_AARCH64_MMU)) {

There's not a great deal of point in this conditional - you won't get
the below exception codes from hardware which doesn't support it AARCH64
page tables.

> +		switch (exception_code) {
> +		case 0xC9 ... 0xCF: return "PERMISSION_FAULT";
> +		case 0xD9 ... 0xDF: return "ACCESS_FLAG";
> +		case 0xE0 ... 0xE7: return "ADDRESS_SIZE_FAULT";
> +		case 0xE8 ... 0xEF: return "MEMORY_ATTRIBUTES_FAULT";
> +		}
> +	}
> +
> +	return "UNKNOWN";
> +}
> +
> +#ifdef CONFIG_PM
> +int panfrost_device_resume(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct panfrost_device *pfdev = platform_get_drvdata(pdev);
> +
> +	panfrost_gpu_soft_reset(pfdev);
> +
> +	/* TODO: Re-enable all other address spaces */
> +	panfrost_gpu_power_on(pfdev);
> +	panfrost_mmu_enable(pfdev, 0);
> +	panfrost_job_enable_interrupts(pfdev);
> +	panfrost_devfreq_resume(pfdev);
> +
> +	return 0;
> +}
> +
> +int panfrost_device_suspend(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct panfrost_device *pfdev = platform_get_drvdata(pdev);
> +
> +	panfrost_devfreq_suspend(pfdev);
> +
> +	if (!panfrost_job_is_idle(pfdev))
> +		return -EBUSY;
> +
> +	panfrost_gpu_power_off(pfdev);
> +
> +	return 0;
> +}
> +#endif
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h
> new file mode 100644
> index 000000000000..f92011d05cc0
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.h
> @@ -0,0 +1,118 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
> +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> +
> +#ifndef __PANFROST_DEVICE_H__
> +#define __PANFROST_DEVICE_H__
> +
> +#include <linux/spinlock.h>
> +#include <drm/drm_device.h>
> +#include <drm/drm_mm.h>
> +#include <drm/gpu_scheduler.h>
> +
> +struct panfrost_device;
> +struct panfrost_mmu;
> +struct panfrost_job_slot;
> +struct panfrost_job;
> +
> +#define NUM_JOB_SLOTS 3
> +
> +struct panfrost_features {
> +	u16 id;
> +	u16 revision;
> +
> +	u64 shader_present;
> +	u64 tiler_present;
> +	u64 l2_present;
> +	u64 stack_present;
> +	u32 as_present;
> +	u32 js_present;
> +
> +	u32 l2_features;
> +	u32 core_features;
> +	u32 tiler_features;
> +	u32 mem_features;
> +	u32 mmu_features;
> +	u32 thread_features;
> +	u32 max_threads;
> +	u32 thread_max_workgroup_sz;
> +	u32 thread_max_barrier_sz;
> +	u32 coherency_features;
> +	u32 texture_features[4];
> +	u32 js_features[16];
> +
> +	u32 nr_core_groups;
> +
> +	unsigned long hw_features[64 / BITS_PER_LONG];
> +	unsigned long hw_issues[64 / BITS_PER_LONG];
> +};
> +
> +struct panfrost_device {
> +	struct device *dev;
> +	struct drm_device *ddev;
> +	struct platform_device *pdev;
> +
> +	spinlock_t hwaccess_lock;
> +
> +	struct drm_mm mm;
> +	spinlock_t mm_lock;
> +
> +	void __iomem *iomem;
> +	struct clk *clock;
> +	struct regulator *regulator;
> +
> +	struct panfrost_features features;
> +
> +	struct panfrost_mmu *mmu;
> +	struct panfrost_job_slot *js;
> +
> +	struct panfrost_job *jobs[NUM_JOB_SLOTS];
> +	struct list_head scheduled_jobs;
> +
> +	struct mutex sched_lock;
> +
> +	struct {
> +		struct devfreq *devfreq;
> +		struct thermal_cooling_device *cooling;
> +		unsigned long cur_freq;
> +		unsigned long cur_volt;
> +		ktime_t busy_time[NUM_JOB_SLOTS];
> +		ktime_t idle_time[NUM_JOB_SLOTS];
> +		ktime_t time_last_update[NUM_JOB_SLOTS];
> +	} devfreq;
> +};
> +
> +struct panfrost_file_priv {
> +	struct panfrost_device *pfdev;
> +
> +	struct drm_sched_entity sched_entity[NUM_JOB_SLOTS];
> +};
> +
> +static inline struct panfrost_device *to_panfrost_device(struct drm_device *ddev)
> +{
> +	return ddev->dev_private;
> +}
> +
> +static inline int panfrost_model_cmp(struct panfrost_device *pfdev, s32 id)
> +{
> +	s32 match_id = pfdev->features.id;
> +
> +	if (match_id & 0xf000)
> +		match_id &= 0xf00f;

I'm puzzled by this, and really not sure if it's going to work out
ignoring the ARCH_MINOR/ARCH_REV fields. But for now there's no real
Bifrost support.

> +	return match_id - id;
> +}
> +
> +static inline bool panfrost_model_eq(struct panfrost_device *pfdev, s32 id)
> +{
> +	return !panfrost_model_cmp(pfdev, id);
> +}
> +
> +int panfrost_device_init(struct panfrost_device *pfdev);
> +void panfrost_device_fini(struct panfrost_device *pfdev);
> +
> +int panfrost_device_resume(struct device *dev);
> +int panfrost_device_suspend(struct device *dev);
> +
> +const char *panfrost_exception_name(struct panfrost_device *pfdev, u32 exception_code);
> +
> +#endif
> diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c
> new file mode 100644
> index 000000000000..57a99032bcc6
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
> @@ -0,0 +1,484 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
> +/* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
> +/* Copyright 2019 Collabora ltd. */
> +
> +#include <linux/dma-mapping.h>
> +#include <linux/module.h>
> +#include <linux/of_platform.h>
> +#include <linux/pagemap.h>
> +#include <linux/pm_runtime.h>
> +#include <drm/panfrost_drm.h>
> +#include <drm/drm_drv.h>
> +#include <drm/drm_ioctl.h>
> +#include <drm/drm_syncobj.h>
> +#include <drm/drm_utils.h>
> +
> +#include "panfrost_device.h"
> +#include "panfrost_devfreq.h"
> +#include "panfrost_gem.h"
> +#include "panfrost_mmu.h"
> +#include "panfrost_job.h"
> +#include "panfrost_gpu.h"
> +
> +static int panfrost_ioctl_get_param(struct drm_device *ddev, void *data, struct drm_file *file)
> +{
> +	struct drm_panfrost_get_param *param = data;
> +	struct panfrost_device *pfdev = ddev->dev_private;
> +
> +	if (param->pad != 0)
> +		return -EINVAL;
> +
> +	switch (param->param) {
> +	case DRM_PANFROST_PARAM_GPU_ID:
> +		param->value = pfdev->features.id;

This is unfortunate naming - this parameter is *not* the GPU_ID. It is
the top half of the GPU_ID which kbase calls the PRODUCT_ID.

I'm also somewhat surprised that you don't need loads of other
properties from the GPU - in particular knowing the number of shader
cores is useful for allocating the right amount of memory for TLS (and
can't be obtained purely from the GPU_ID).

> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int panfrost_ioctl_create_bo(struct drm_device *dev, void *data,
> +		struct drm_file *file)
> +{
> +	int ret;
> +	struct drm_gem_shmem_object *shmem;
> +	struct drm_panfrost_create_bo *args = data;
> +
> +	if (!args->size || args->flags)
> +		return -EINVAL;
> +
> +	shmem = drm_gem_shmem_create_with_handle(file, dev, args->size,
> +						 &args->handle);
> +	if (IS_ERR(shmem))
> +		return PTR_ERR(shmem);
> +
> +	ret = panfrost_mmu_map(to_panfrost_bo(&shmem->base));
> +	if (ret)
> +		goto err_free;
> +
> +	args->offset = to_panfrost_bo(&shmem->base)->node.start << PAGE_SHIFT;
> +
> +	return 0;
> +
> +err_free:
> +	drm_gem_object_put_unlocked(&shmem->base);
> +	return ret;
> +}
> +
> +/**
> + * panfrost_lookup_bos() - Sets up job->bo[] with the GEM objects
> + * referenced by the job.
> + * @dev: DRM device
> + * @file_priv: DRM file for this fd
> + * @args: IOCTL args
> + * @job: job being set up
> + *
> + * Resolve handles from userspace to BOs and attach them to job.
> + *
> + * Note that this function doesn't need to unreference the BOs on
> + * failure, because that will happen at panfrost_job_cleanup() time.
> + */
> +static int
> +panfrost_lookup_bos(struct drm_device *dev,
> +		  struct drm_file *file_priv,
> +		  struct drm_panfrost_submit *args,
> +		  struct panfrost_job *job)
> +{
> +	u32 *handles;
> +	int ret = 0;
> +
> +	job->bo_count = args->bo_handle_count;
> +
> +	if (!job->bo_count)
> +		return 0;
> +
> +	job->bos = kvmalloc_array(job->bo_count,
> +				  sizeof(struct drm_gem_object *),
> +				  GFP_KERNEL | __GFP_ZERO);
> +	if (!job->bos)

If we return here then job->bo_count has been set, but job->bos is
invalid - this means that panfrost_job_cleanup() will then dereference
NULL. Although maybe this is better fixed in panfrost_job_cleanup().

> +		return -ENOMEM;
> +
> +	job->implicit_fences = kvmalloc_array(job->bo_count,
> +				  sizeof(struct dma_fence *),
> +				  GFP_KERNEL | __GFP_ZERO);
> +	if (!job->implicit_fences)
> +		return -ENOMEM;
> +
> +	handles = kvmalloc_array(job->bo_count, sizeof(u32), GFP_KERNEL);
> +	if (!handles) {
> +		ret = -ENOMEM;
> +		goto fail;
> +	}
> +
> +	if (copy_from_user(handles,
> +			   (void __user *)(uintptr_t)args->bo_handles,
> +			   job->bo_count * sizeof(u32))) {
> +		ret = -EFAULT;
> +		DRM_DEBUG("Failed to copy in GEM handles\n");
> +		goto fail;
> +	}
> +
> +	ret = drm_gem_objects_lookup(file_priv, handles, job->bo_count, job->bos);
> +
> +fail:
> +	kvfree(handles);
> +	return ret;
> +}
> +
> +/**
> + * panfrost_copy_in_sync() - Sets up job->in_fences[] with the sync objects
> + * referenced by the job.
> + * @dev: DRM device
> + * @file_priv: DRM file for this fd
> + * @args: IOCTL args
> + * @job: job being set up
> + *
> + * Resolve syncobjs from userspace to fences and attach them to job.
> + *
> + * Note that this function doesn't need to unreference the fences on
> + * failure, because that will happen at panfrost_job_cleanup() time.
> + */
> +static int
> +panfrost_copy_in_sync(struct drm_device *dev,
> +		  struct drm_file *file_priv,
> +		  struct drm_panfrost_submit *args,
> +		  struct panfrost_job *job)
> +{
> +	u32 *handles;
> +	int ret = 0;
> +	int i;
> +
> +	job->in_fence_count = args->in_sync_count;
> +
> +	if (!job->in_fence_count)
> +		return 0;
> +
> +	job->in_fences = kvmalloc_array(job->in_fence_count,
> +				  sizeof(struct drm_panfrost_gem_object *),
> +				  GFP_KERNEL | __GFP_ZERO);
> +	if (!job->in_fences) {

Same issue as above, in_fence_count is set but job_in_fences is NULL.
panfrost_job_cleanup() will then attempt to walk the NULL array...

Also this should probably be kvzalloc - in case the call below to
drm_syncobj_find_fence() fails.

> +		DRM_DEBUG("Failed to allocate job in fences\n");
> +		return -ENOMEM;
> +	}
> +
> +	handles = kvmalloc_array(job->in_fence_count, sizeof(u32), GFP_KERNEL);
> +	if (!handles) {
> +		ret = -ENOMEM;
> +		DRM_DEBUG("Failed to allocate incoming syncobj handles\n");
> +		goto fail;
> +	}
> +
> +	if (copy_from_user(handles,
> +			   (void __user *)(uintptr_t)args->in_syncs,
> +			   job->in_fence_count * sizeof(u32))) {
> +		ret = -EFAULT;
> +		DRM_DEBUG("Failed to copy in syncobj handles\n");
> +		goto fail;
> +	}
> +
> +	for (i = 0; i < job->in_fence_count; i++) {
> +		ret = drm_syncobj_find_fence(file_priv, handles[i], 0, 0,
> +					     &job->in_fences[i]);
> +		if (ret == -EINVAL)
> +			goto fail;
> +	}
> +
> +fail:

s/fail/out/ since we hit this in the success condition too? Also in
other places.

> +	kvfree(handles);
> +	return ret;
> +}
> +
> +static int panfrost_ioctl_submit(struct drm_device *dev, void *data,
> +		struct drm_file *file)
> +{
> +	struct panfrost_device *pfdev = dev->dev_private;
> +	struct drm_panfrost_submit *args = data;
> +	struct drm_syncobj *sync_out;
> +	struct panfrost_job *job;
> +	int ret = 0;
> +
> +	job = kcalloc(1, sizeof(*job), GFP_KERNEL);
> +	if (!job)
> +		return -ENOMEM;
> +
> +	kref_init(&job->refcount);
> +
> +	job->pfdev = pfdev;
> +	job->jc = args->jc;
> +	job->requirements = args->requirements;
> +	job->flush_id = panfrost_gpu_get_latest_flush_id(pfdev);
> +	job->file_priv = file->driver_priv;
> +
> +	ret = panfrost_copy_in_sync(dev, file, args, job);
> +	if (ret)
> +		goto fail;
> +
> +	ret = panfrost_lookup_bos(dev, file, args, job);
> +	if (ret)
> +		goto fail;
> +
> +	ret = panfrost_job_push(job);
> +	if (ret)
> +		goto fail;
> +
> +	/* Update the return sync object for the job */
> +	sync_out = drm_syncobj_find(file, args->out_sync);
> +	if (sync_out) {
> +		drm_syncobj_replace_fence(sync_out, job->render_done_fence);
> +		drm_syncobj_put(sync_out);
> +	}
> +
> +fail:
> +	panfrost_job_put(job);
> +
> +	return ret;
> +}
> +
> +static int
> +panfrost_ioctl_wait_bo(struct drm_device *dev, void *data,
> +		       struct drm_file *file_priv)
> +{
> +	long ret;
> +	struct drm_panfrost_wait_bo *args = data;
> +	struct drm_gem_object *gem_obj;
> +	unsigned long timeout = drm_timeout_abs_to_jiffies(args->timeout_ns);
> +
> +	if (args->pad)
> +		return -EINVAL;
> +
> +	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
> +	if (!gem_obj)
> +		return -ENOENT;
> +
> +	ret = reservation_object_wait_timeout_rcu(gem_obj->resv, true,
> +						  true, timeout);
> +	if (!ret)
> +		ret = timeout ? -ETIMEDOUT : -EBUSY;
> +
> +	drm_gem_object_put_unlocked(gem_obj);
> +
> +	return ret;
> +}
> +
> +static int panfrost_ioctl_mmap_bo(struct drm_device *dev, void *data,
> +		      struct drm_file *file_priv)
> +{
> +	struct drm_panfrost_mmap_bo *args = data;
> +	struct drm_gem_object *gem_obj;
> +	int ret;
> +
> +	if (args->flags != 0) {
> +		DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
> +		return -EINVAL;
> +	}
> +
> +	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
> +	if (!gem_obj) {
> +		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
> +		return -ENOENT;
> +	}
> +
> +	ret = drm_gem_create_mmap_offset(gem_obj);
> +	if (ret == 0)
> +		args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
> +	drm_gem_object_put_unlocked(gem_obj);
> +
> +	return ret;
> +}
> +
> +static int panfrost_ioctl_get_bo_offset(struct drm_device *dev, void *data,
> +			    struct drm_file *file_priv)
> +{
> +	struct drm_panfrost_get_bo_offset *args = data;
> +	struct drm_gem_object *gem_obj;
> +	struct panfrost_gem_object *bo;
> +
> +	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
> +	if (!gem_obj) {
> +		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
> +		return -ENOENT;
> +	}
> +	bo = to_panfrost_bo(gem_obj);
> +
> +	args->offset = bo->node.start << PAGE_SHIFT;
> +
> +	drm_gem_object_put_unlocked(gem_obj);
> +	return 0;
> +}
> +
> +static int
> +panfrost_open(struct drm_device *dev, struct drm_file *file)
> +{
> +	struct panfrost_device *pfdev = dev->dev_private;
> +	struct panfrost_file_priv *panfrost_priv;
> +
> +	panfrost_priv = kzalloc(sizeof(*panfrost_priv), GFP_KERNEL);
> +	if (!panfrost_priv)
> +		return -ENOMEM;
> +
> +	panfrost_priv->pfdev = pfdev;
> +	file->driver_priv = panfrost_priv;
> +
> +	return panfrost_job_open(panfrost_priv);
> +}
> +
> +static void
> +panfrost_postclose(struct drm_device *dev, struct drm_file *file)
> +{
> +	struct panfrost_file_priv *panfrost_priv = file->driver_priv;
> +
> +	panfrost_job_close(panfrost_priv);
> +
> +	kfree(panfrost_priv);
> +}
> +
> +/* DRM_AUTH is required on SUBMIT for now, while all clients share a single
> + * address space.  Note that render nodes would be able to submit jobs that
> + * could access BOs from clients authenticated with the master node.
> + */
> +static const struct drm_ioctl_desc panfrost_drm_driver_ioctls[] = {
> +#define PANFROST_IOCTL(n, func, flags) \
> +	DRM_IOCTL_DEF_DRV(PANFROST_##n, panfrost_ioctl_##func, flags)
> +
> +	PANFROST_IOCTL(SUBMIT,		submit,		DRM_RENDER_ALLOW | DRM_AUTH),
> +	PANFROST_IOCTL(WAIT_BO,		wait_bo,	DRM_RENDER_ALLOW),
> +	PANFROST_IOCTL(CREATE_BO,	create_bo,	DRM_RENDER_ALLOW),
> +	PANFROST_IOCTL(MMAP_BO,		mmap_bo,	DRM_RENDER_ALLOW),
> +	PANFROST_IOCTL(GET_PARAM,	get_param,	DRM_RENDER_ALLOW),
> +	PANFROST_IOCTL(GET_BO_OFFSET,	get_bo_offset,	DRM_RENDER_ALLOW),
> +};
> +
> +DEFINE_DRM_GEM_SHMEM_FOPS(panfrost_drm_driver_fops);
> +
> +static struct drm_driver panfrost_drm_driver = {
> +	.driver_features	= DRIVER_RENDER | DRIVER_GEM | DRIVER_PRIME |
> +				  DRIVER_SYNCOBJ,
> +	.open			= panfrost_open,
> +	.postclose		= panfrost_postclose,
> +	.ioctls			= panfrost_drm_driver_ioctls,
> +	.num_ioctls		= ARRAY_SIZE(panfrost_drm_driver_ioctls),
> +	.fops			= &panfrost_drm_driver_fops,
> +	.name			= "panfrost",
> +	.desc			= "panfrost DRM",
> +	.date			= "20180908",
> +	.major			= 1,
> +	.minor			= 0,
> +
> +	.gem_create_object	= panfrost_gem_create_object,
> +	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd,
> +	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle,
> +	.gem_prime_import_sg_table = panfrost_gem_prime_import_sg_table,
> +	.gem_prime_mmap		= drm_gem_prime_mmap,
> +};
> +
> +static int panfrost_probe(struct platform_device *pdev)
> +{
> +	struct panfrost_device *pfdev;
> +	struct drm_device *ddev;
> +	int err;
> +
> +	pfdev = devm_kzalloc(&pdev->dev, sizeof(*pfdev), GFP_KERNEL);
> +	if (!pfdev)
> +		return -ENOMEM;
> +
> +	pfdev->pdev = pdev;
> +	pfdev->dev = &pdev->dev;
> +
> +	platform_set_drvdata(pdev, pfdev);
> +
> +	/* Allocate and initialze the DRM device. */
> +	ddev = drm_dev_alloc(&panfrost_drm_driver, &pdev->dev);
> +	if (IS_ERR(ddev))
> +		return PTR_ERR(ddev);
> +
> +	ddev->dev_private = pfdev;
> +	pfdev->ddev = ddev;
> +
> +	spin_lock_init(&pfdev->mm_lock);
> +
> +	/* 4G enough for now. can be 48-bit */
> +	drm_mm_init(&pfdev->mm, SZ_32M >> PAGE_SHIFT, SZ_4G);
> +
> +	pm_runtime_use_autosuspend(pfdev->dev);
> +	pm_runtime_set_autosuspend_delay(pfdev->dev, 50); /* ~3 frames */
> +	pm_runtime_enable(pfdev->dev);
> +
> +	err = panfrost_device_init(pfdev);
> +	if (err) {
> +		dev_err(&pdev->dev, "Fatal error during GPU init\n");
> +		goto err_out0;
> +	}
> +
> +	err = panfrost_devfreq_init(pfdev);
> +	if (err) {
> +		dev_err(&pdev->dev, "Fatal error during devfreq init\n");
> +		goto err_out1;
> +	}
> +
> +	/*
> +	 * Register the DRM device with the core and the connectors with
> +	 * sysfs
> +	 */
> +	err = drm_dev_register(ddev, 0);
> +	if (err < 0)
> +		goto err_out1;
> +
> +	return 0;
> +
> +err_out1:
> +	panfrost_device_fini(pfdev);
> +err_out0:
> +	drm_dev_put(ddev);
> +	return err;
> +}
> +
> +static int panfrost_remove(struct platform_device *pdev)
> +{
> +	struct panfrost_device *pfdev = platform_get_drvdata(pdev);
> +	struct drm_device *ddev = pfdev->ddev;
> +
> +	drm_dev_unregister(ddev);
> +	pm_runtime_get_sync(pfdev->dev);
> +	pm_runtime_put_sync_autosuspend(pfdev->dev);
> +	pm_runtime_disable(pfdev->dev);
> +	panfrost_device_fini(pfdev);
> +	drm_dev_put(ddev);
> +	return 0;
> +}
> +
> +static const struct of_device_id dt_match[] = {
> +	{ .compatible = "arm,mali-t604" },
> +	{ .compatible = "arm,mali-t624" },
> +	{ .compatible = "arm,mali-t628" },
> +	{ .compatible = "arm,mali-t720" },
> +	{ .compatible = "arm,mali-t760" },
> +	{ .compatible = "arm,mali-t820" },
> +	{ .compatible = "arm,mali-t830" },
> +	{ .compatible = "arm,mali-t860" },
> +	{ .compatible = "arm,mali-t880" },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, dt_match);
> +
> +static const struct dev_pm_ops panfrost_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume)
> +	SET_RUNTIME_PM_OPS(panfrost_device_suspend, panfrost_device_resume, NULL)
> +};
> +
> +static struct platform_driver panfrost_driver = {
> +	.probe		= panfrost_probe,
> +	.remove		= panfrost_remove,
> +	.driver		= {
> +		.name	= "panfrost",
> +		.pm	= &panfrost_pm_ops,
> +		.of_match_table = dt_match,
> +	},
> +};
> +module_platform_driver(panfrost_driver);
> +
> +MODULE_AUTHOR("Panfrost Project Developers");
> +MODULE_DESCRIPTION("Panfrost DRM Driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/gpu/drm/panfrost/panfrost_features.h b/drivers/gpu/drm/panfrost/panfrost_features.h
> new file mode 100644
> index 000000000000..5056777c7744
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_features.h
> @@ -0,0 +1,309 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* (C) COPYRIGHT 2014-2018 ARM Limited. All rights reserved. */
> +/* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
> +#ifndef __PANFROST_FEATURES_H__
> +#define __PANFROST_FEATURES_H__
> +
> +#include <linux/bitops.h>
> +
> +#include "panfrost_device.h"
> +
> +enum panfrost_hw_feature {
> +	HW_FEATURE_JOBCHAIN_DISAMBIGUATION,
> +	HW_FEATURE_PWRON_DURING_PWROFF_TRANS,
> +	HW_FEATURE_XAFFINITY,
> +	HW_FEATURE_OUT_OF_ORDER_EXEC,
> +	HW_FEATURE_MRT,
> +	HW_FEATURE_BRNDOUT_CC,
> +	HW_FEATURE_INTERPIPE_REG_ALIASING,
> +	HW_FEATURE_LD_ST_TILEBUFFER,
> +	HW_FEATURE_MSAA_16X,
> +	HW_FEATURE_32_BIT_UNIFORM_ADDRESS,
> +	HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL,
> +	HW_FEATURE_OPTIMIZED_COVERAGE_MASK,
> +	HW_FEATURE_T7XX_PAIRING_RULES,
> +	HW_FEATURE_LD_ST_LEA_TEX,
> +	HW_FEATURE_LINEAR_FILTER_FLOAT,
> +	HW_FEATURE_WORKGROUP_ROUND_MULTIPLE_OF_4,
> +	HW_FEATURE_IMAGES_IN_FRAGMENT_SHADERS,
> +	HW_FEATURE_TEST4_DATUM_MODE,
> +	HW_FEATURE_NEXT_INSTRUCTION_TYPE,
> +	HW_FEATURE_BRNDOUT_KILL,
> +	HW_FEATURE_WARPING,
> +	HW_FEATURE_V4,
> +	HW_FEATURE_FLUSH_REDUCTION,
> +	HW_FEATURE_PROTECTED_MODE,
> +	HW_FEATURE_COHERENCY_REG,
> +	HW_FEATURE_PROTECTED_DEBUG_MODE,
> +	HW_FEATURE_AARCH64_MMU,
> +	HW_FEATURE_TLS_HASHING,
> +	HW_FEATURE_THREAD_GROUP_SPLIT,
> +	HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG,
> +};
> +
> +#define hw_features_t600 (\
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
> +	BIT_ULL(HW_FEATURE_V4))
> +
> +#define hw_features_t620 (\
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
> +	BIT_ULL(HW_FEATURE_V4))
> +
> +#define hw_features_t720 (\
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
> +	BIT_ULL(HW_FEATURE_OPTIMIZED_COVERAGE_MASK) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
> +	BIT_ULL(HW_FEATURE_WORKGROUP_ROUND_MULTIPLE_OF_4) | \
> +	BIT_ULL(HW_FEATURE_WARPING) | \
> +	BIT_ULL(HW_FEATURE_V4))
> +
> +
> +#define hw_features_t760 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_MSAA_16X) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT))
> +
> +// T860
> +#define hw_features_t860 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_MSAA_16X) | \
> +	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT))
> +
> +#define hw_features_t880 hw_features_t860
> +
> +#define hw_features_t830 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_WARPING) | \
> +	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT))
> +
> +#define hw_features_t820 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_WARPING) | \
> +	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT))
> +
> +#define hw_features_g71 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_WARPING) | \
> +	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_MSAA_16X) | \
> +	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
> +	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
> +	BIT_ULL(HW_FEATURE_COHERENCY_REG))
> +
> +#define hw_features_g72 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_WARPING) | \
> +	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_MSAA_16X) | \
> +	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
> +	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
> +	BIT_ULL(HW_FEATURE_COHERENCY_REG))
> +
> +#define hw_features_g51 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_WARPING) | \
> +	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_MSAA_16X) | \
> +	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
> +	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
> +	BIT_ULL(HW_FEATURE_COHERENCY_REG))
> +
> +#define hw_features_g52 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_WARPING) | \
> +	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_MSAA_16X) | \
> +	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
> +	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
> +	BIT_ULL(HW_FEATURE_COHERENCY_REG))
> +
> +#define hw_features_g76 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_WARPING) | \
> +	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_MSAA_16X) | \
> +	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
> +	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
> +	BIT_ULL(HW_FEATURE_COHERENCY_REG) | \
> +	BIT_ULL(HW_FEATURE_AARCH64_MMU) | \
> +	BIT_ULL(HW_FEATURE_TLS_HASHING) | \
> +	BIT_ULL(HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG))
> +
> +#define hw_features_g31 (\
> +	BIT_ULL(HW_FEATURE_JOBCHAIN_DISAMBIGUATION) | \
> +	BIT_ULL(HW_FEATURE_PWRON_DURING_PWROFF_TRANS) | \
> +	BIT_ULL(HW_FEATURE_XAFFINITY) | \
> +	BIT_ULL(HW_FEATURE_WARPING) | \
> +	BIT_ULL(HW_FEATURE_INTERPIPE_REG_ALIASING) | \
> +	BIT_ULL(HW_FEATURE_32_BIT_UNIFORM_ADDRESS) | \
> +	BIT_ULL(HW_FEATURE_ATTR_AUTO_TYPE_INFERRAL) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_CC) | \
> +	BIT_ULL(HW_FEATURE_BRNDOUT_KILL) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_LEA_TEX) | \
> +	BIT_ULL(HW_FEATURE_LD_ST_TILEBUFFER) | \
> +	BIT_ULL(HW_FEATURE_LINEAR_FILTER_FLOAT) | \
> +	BIT_ULL(HW_FEATURE_MRT) | \
> +	BIT_ULL(HW_FEATURE_MSAA_16X) | \
> +	BIT_ULL(HW_FEATURE_NEXT_INSTRUCTION_TYPE) | \
> +	BIT_ULL(HW_FEATURE_OUT_OF_ORDER_EXEC) | \
> +	BIT_ULL(HW_FEATURE_T7XX_PAIRING_RULES) | \
> +	BIT_ULL(HW_FEATURE_TEST4_DATUM_MODE) | \
> +	BIT_ULL(HW_FEATURE_THREAD_GROUP_SPLIT) | \
> +	BIT_ULL(HW_FEATURE_FLUSH_REDUCTION) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_MODE) | \
> +	BIT_ULL(HW_FEATURE_PROTECTED_DEBUG_MODE) | \
> +	BIT_ULL(HW_FEATURE_COHERENCY_REG) | \
> +	BIT_ULL(HW_FEATURE_AARCH64_MMU) | \
> +	BIT_ULL(HW_FEATURE_TLS_HASHING) | \
> +	BIT_ULL(HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG))
> +
> +static inline bool panfrost_has_hw_feature(struct panfrost_device *pfdev,
> +					   enum panfrost_hw_feature feat)
> +{
> +	return test_bit(feat, pfdev->features.hw_features);
> +}
> +
> +#endif
> diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c b/drivers/gpu/drm/panfrost/panfrost_gem.c
> new file mode 100644
> index 000000000000..31f13f49277a
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_gem.c
> @@ -0,0 +1,92 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> +
> +#include <linux/err.h>
> +#include <linux/slab.h>
> +#include <linux/dma-buf.h>
> +#include <linux/dma-mapping.h>
> +
> +#include <drm/panfrost_drm.h>
> +#include "panfrost_device.h"
> +#include "panfrost_gem.h"
> +#include "panfrost_mmu.h"
> +
> +/* Called DRM core on the last userspace/kernel unreference of the
> + * BO.
> + */
> +void panfrost_gem_free_object(struct drm_gem_object *obj)
> +{
> +	struct panfrost_gem_object *bo = to_panfrost_bo(obj);
> +	struct panfrost_device *pfdev = obj->dev->dev_private;
> +
> +	panfrost_mmu_unmap(bo);
> +
> +	spin_lock(&pfdev->mm_lock);
> +	drm_mm_remove_node(&bo->node);
> +	spin_unlock(&pfdev->mm_lock);
> +
> +	drm_gem_shmem_free_object(obj);
> +}
> +
> +static const struct drm_gem_object_funcs panfrost_gem_funcs = {
> +	.free = panfrost_gem_free_object,
> +	.print_info = drm_gem_shmem_print_info,
> +	.pin = drm_gem_shmem_pin,
> +	.unpin = drm_gem_shmem_unpin,
> +	.get_sg_table = drm_gem_shmem_get_sg_table,
> +	.vmap = drm_gem_shmem_vmap,
> +	.vunmap = drm_gem_shmem_vunmap,
> +	.vm_ops = &drm_gem_shmem_vm_ops,
> +};
> +
> +/**
> + * panfrost_gem_create_object - Implementation of driver->gem_create_object.
> + * @dev: DRM device
> + * @size: Size in bytes of the memory the object will reference
> + *
> + * This lets the GEM helpers allocate object structs for us, and keep
> + * our BO stats correct.
> + */
> +struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t size)
> +{
> +	int ret;
> +	struct panfrost_device *pfdev = dev->dev_private;
> +	struct panfrost_gem_object *obj;
> +
> +	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
> +	if (!obj)
> +		return NULL;
> +
> +	obj->base.base.funcs = &panfrost_gem_funcs;
> +
> +	spin_lock(&pfdev->mm_lock);
> +	ret = drm_mm_insert_node(&pfdev->mm, &obj->node,
> +				 roundup(size, PAGE_SIZE) >> PAGE_SHIFT);
> +	spin_unlock(&pfdev->mm_lock);
> +	if (ret)
> +		goto free_obj;
> +
> +	return &obj->base.base;
> +
> +free_obj:
> +	kfree(obj);
> +	return ERR_PTR(ret);
> +}
> +
> +struct drm_gem_object *
> +panfrost_gem_prime_import_sg_table(struct drm_device *dev,
> +				   struct dma_buf_attachment *attach,
> +				   struct sg_table *sgt)
> +{
> +	struct drm_gem_object *obj;
> +	struct panfrost_gem_object *pobj;
> +
> +	obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);

This can fail (e.g. -ENOMEM).

> +	pobj = to_panfrost_bo(obj);
> +
> +	obj->resv = attach->dmabuf->resv;
> +
> +	panfrost_mmu_map(pobj);
> +
> +	return obj;
> +}
> diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.h b/drivers/gpu/drm/panfrost/panfrost_gem.h
> new file mode 100644
> index 000000000000..045000eb5fcf
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_gem.h
> @@ -0,0 +1,29 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> +
> +#ifndef __PANFROST_GEM_H__
> +#define __PANFROST_GEM_H__
> +
> +#include <drm/drm_gem_shmem_helper.h>
> +#include <drm/drm_mm.h>
> +
> +struct panfrost_gem_object {
> +	struct drm_gem_shmem_object base;
> +
> +	struct drm_mm_node node;
> +};
> +
> +static inline
> +struct  panfrost_gem_object *to_panfrost_bo(struct drm_gem_object *obj)
> +{
> +	return container_of(to_drm_gem_shmem_obj(obj), struct panfrost_gem_object, base);
> +}
> +
> +struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t size);
> +
> +struct drm_gem_object *
> +panfrost_gem_prime_import_sg_table(struct drm_device *dev,
> +				   struct dma_buf_attachment *attach,
> +				   struct sg_table *sgt);
> +
> +#endif /* __PANFROST_GEM_H__ */
> diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.c b/drivers/gpu/drm/panfrost/panfrost_gpu.c
> new file mode 100644
> index 000000000000..867e2ba3a761
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_gpu.c
> @@ -0,0 +1,374 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
> +/* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
> +/* Copyright 2019 Collabora ltd. */
> +#include <linux/bitmap.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +#include <linux/platform_device.h>
> +
> +#include "panfrost_device.h"
> +#include "panfrost_features.h"
> +#include "panfrost_issues.h"
> +#include "panfrost_gpu.h"
> +#include "panfrost_regs.h"
> +
> +#define gpu_write(dev, reg, data) writel(data, dev->iomem + reg)
> +#define gpu_read(dev, reg) readl(dev->iomem + reg)
> +
> +static irqreturn_t panfrost_gpu_irq_handler(int irq, void *data)
> +{
> +	struct panfrost_device *pfdev = data;
> +	u32 state = gpu_read(pfdev, GPU_INT_STAT);
> +	u32 fault_status = gpu_read(pfdev, GPU_FAULT_STATUS);
> +	u64 address;
> +	bool done = false;
> +
> +	if (!state)
> +		return IRQ_NONE;
> +
> +	if (state & GPU_IRQ_MASK_ERROR) {
> +		address = (u64) gpu_read(pfdev, GPU_FAULT_ADDRESS_HI) << 32;
> +		address |= gpu_read(pfdev, GPU_FAULT_ADDRESS_LO);
> +
> +		dev_warn(pfdev->dev, "GPU Fault 0x%08x (%s) at 0x%016llx\n",
> +			 fault_status & 0xFF, panfrost_exception_name(pfdev, fault_status),
> +			 address);
> +
> +		if (state & GPU_IRQ_MULTIPLE_FAULT)
> +			dev_warn(pfdev->dev, "There were multiple GPU faults - some have not been reported\n");
> +
> +		gpu_write(pfdev, GPU_INT_MASK, 0);

Do you intend to mask off future GPU interrupts?

> +
> +		done = true;

'done' isn't used - can be removed.

> +	}
> +
> +	gpu_write(pfdev, GPU_INT_CLEAR, state);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +int panfrost_gpu_soft_reset(struct panfrost_device *pfdev)
> +{
> +	int ret;
> +	u32 val;
> +
> +	gpu_write(pfdev, GPU_INT_MASK, 0);
> +	gpu_write(pfdev, GPU_INT_CLEAR, GPU_IRQ_RESET_COMPLETED);
> +	gpu_write(pfdev, GPU_CMD, GPU_CMD_SOFT_RESET);
> +
> +	ret = readl_relaxed_poll_timeout(pfdev->iomem + GPU_INT_RAWSTAT,
> +		val, val & GPU_IRQ_RESET_COMPLETED, 100, 10000);
> +
> +	if (ret) {
> +		dev_err(pfdev->dev, "gpu soft reset timed out\n");
> +		return ret;
> +	}
> +
> +	gpu_write(pfdev, GPU_INT_CLEAR, GPU_IRQ_MASK_ALL);
> +	gpu_write(pfdev, GPU_INT_MASK, GPU_IRQ_MASK_ALL);
> +
> +	return 0;
> +}
> +
> +static void panfrost_gpu_init_quirks(struct panfrost_device *pfdev)
> +{
> +	u32 quirks = 0;
> +
> +	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_8443) ||
> +	    panfrost_has_hw_issue(pfdev, HW_ISSUE_11035))
> +		quirks |= SC_LS_PAUSEBUFFER_DISABLE;
> +
> +	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_10327))
> +		quirks |= SC_SDC_DISABLE_OQ_DISCARD;
> +
> +	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_10797))
> +		quirks |= SC_ENABLE_TEXGRD_FLAGS;
> +
> +	if (!panfrost_has_hw_issue(pfdev, GPUCORE_1619)) {
> +		if (panfrost_model_cmp(pfdev, 0x750) < 0) /* T60x, T62x, T72x */
> +			quirks |= SC_LS_ATTR_CHECK_DISABLE;
> +		else if (panfrost_model_cmp(pfdev, 0x880) <= 0) /* T76x, T8xx */
> +			quirks |= SC_LS_ALLOW_ATTR_TYPES;
> +	}
> +
> +	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_TLS_HASHING))
> +		quirks |= SC_TLS_HASH_ENABLE;
> +
> +	if (quirks)
> +		gpu_write(pfdev, GPU_SHADER_CONFIG, quirks);
> +
> +
> +	quirks = gpu_read(pfdev, GPU_TILER_CONFIG);
> +
> +	/* Set tiler clock gate override if required */
> +	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_T76X_3953))
> +		quirks |= TC_CLOCK_GATE_OVERRIDE;
> +
> +	gpu_write(pfdev, GPU_TILER_CONFIG, quirks);
> +
> +
> +	quirks = gpu_read(pfdev, GPU_L2_MMU_CONFIG);
> +
> +	/* Limit read & write ID width for AXI */
> +	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_3BIT_EXT_RW_L2_MMU_CONFIG))
> +		quirks &= ~(L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_READS |
> +			    L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_WRITES);
> +	else
> +		quirks &= ~(L2_MMU_CONFIG_LIMIT_EXTERNAL_READS |
> +			    L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES);
> +
> +#if 0
> +	if (kbdev->system_coherency == COHERENCY_ACE) {
> +		/* Allow memory configuration disparity to be ignored, we
> +		 * optimize the use of shared memory and thus we expect
> +		 * some disparity in the memory configuration */
> +		quirks |= L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY;
> +	}
> +#endif
> +	gpu_write(pfdev, GPU_L2_MMU_CONFIG, quirks);
> +
> +	quirks = 0;
> +	if ((panfrost_model_eq(pfdev, 0x860) || panfrost_model_eq(pfdev, 0x880)) &&
> +	    pfdev->features.revision >= 0x2000)
> +		quirks |= JM_MAX_JOB_THROTTLE_LIMIT << JM_JOB_THROTTLE_LIMIT_SHIFT;
> +	else if (panfrost_model_eq(pfdev, 0x6000) &&
> +		 pfdev->features.coherency_features == COHERENCY_ACE)
> +		quirks |= (COHERENCY_ACE_LITE | COHERENCY_ACE) <<
> +			   JM_FORCE_COHERENCY_FEATURES_SHIFT;
> +
> +	if (quirks)
> +		gpu_write(pfdev, GPU_JM_CONFIG, quirks);
> +}
> +
> +#define MAX_HW_REVS 6
> +
> +struct panfrost_model {
> +	const char *name;
> +	u32 id;
> +	u32 id_mask;
> +	u64 features;
> +	u64 issues;
> +	struct {
> +		u32 revision;
> +		u64 issues;
> +	} revs[MAX_HW_REVS];
> +};
> +
> +#define GPU_MODEL(_name, _id, ...) \
> +{\
> +	.name = __stringify(_name),				\
> +	.id = _id,						\
> +	.features = hw_features_##_name,			\
> +	.issues = hw_issues_##_name,				\
> +	.revs = { __VA_ARGS__ },				\
> +}
> +
> +#define GPU_REV_EXT(name, _rev, _p, _s, stat) \
> +{\
> +	.revision = (_rev) << 12 | (_p) << 4 | (_s),		\
> +	.issues = hw_issues_##name##_r##_rev##p##_p##stat,	\
> +}
> +#define GPU_REV(name, r, p) GPU_REV_EXT(name, r, p, 0, )
> +
> +static const struct panfrost_model gpu_models[] = {
> +	/* T60x has an oddball version */
> +	GPU_MODEL(t600, 0x600,
> +		GPU_REV_EXT(t600, 0, 0, 1, _15dev0)),
> +	GPU_MODEL(t620, 0x620,
> +		GPU_REV(t620, 0, 1), GPU_REV(t620, 1, 0)),
> +	GPU_MODEL(t720, 0x720),
> +	GPU_MODEL(t760, 0x750,
> +		GPU_REV(t760, 0, 0), GPU_REV(t760, 0, 1),
> +		GPU_REV_EXT(t760, 0, 1, 0, _50rel0),
> +		GPU_REV(t760, 0, 2), GPU_REV(t760, 0, 3)),
> +	GPU_MODEL(t820, 0x820),
> +	GPU_MODEL(t830, 0x830),
> +	GPU_MODEL(t860, 0x860),
> +	GPU_MODEL(t880, 0x880),
> +
> +	GPU_MODEL(g71, 0x6000,
> +		GPU_REV_EXT(g71, 0, 0, 1, _05dev0)),
> +	GPU_MODEL(g72, 0x6001),
> +	GPU_MODEL(g51, 0x7000),
> +	GPU_MODEL(g76, 0x7001),
> +	GPU_MODEL(g52, 0x7002),
> +	GPU_MODEL(g31, 0x7003,
> +		GPU_REV(g31, 1, 0)),
> +};
> +
> +static void panfrost_gpu_init_features(struct panfrost_device *pfdev)
> +{
> +	u32 gpu_id, num_js, major, minor, status, rev;
> +	const char *name = "unknown";
> +	u64 hw_feat = 0;
> +	u64 hw_issues = hw_issues_all;
> +	const struct panfrost_model *model;
> +	int i;
> +
> +	pfdev->features.l2_features = gpu_read(pfdev, GPU_L2_FEATURES);
> +	pfdev->features.core_features = gpu_read(pfdev, GPU_CORE_FEATURES);
> +	pfdev->features.tiler_features = gpu_read(pfdev, GPU_TILER_FEATURES);
> +	pfdev->features.mem_features = gpu_read(pfdev, GPU_MEM_FEATURES);
> +	pfdev->features.mmu_features = gpu_read(pfdev, GPU_MMU_FEATURES);
> +	pfdev->features.thread_features = gpu_read(pfdev, GPU_THREAD_FEATURES);
> +	pfdev->features.coherency_features = gpu_read(pfdev, GPU_COHERENCY_FEATURES);
> +	for (i = 0; i < 4; i++)
> +		pfdev->features.texture_features[i] = gpu_read(pfdev, GPU_TEXTURE_FEATURES(i));
> +
> +	pfdev->features.as_present = gpu_read(pfdev, GPU_AS_PRESENT);
> +
> +	pfdev->features.js_present = gpu_read(pfdev, GPU_JS_PRESENT);
> +	num_js = hweight32(pfdev->features.js_present);
> +	for (i = 0; i < num_js; i++)
> +		pfdev->features.js_features[i] = gpu_read(pfdev, GPU_JS_FEATURES(i));
> +
> +	pfdev->features.shader_present = gpu_read(pfdev, GPU_SHADER_PRESENT_LO);
> +	pfdev->features.shader_present |= (u64)gpu_read(pfdev, GPU_SHADER_PRESENT_HI) << 32;
> +
> +	pfdev->features.tiler_present = gpu_read(pfdev, GPU_TILER_PRESENT_LO);
> +	pfdev->features.tiler_present |= (u64)gpu_read(pfdev, GPU_TILER_PRESENT_HI) << 32;
> +
> +	pfdev->features.l2_present = gpu_read(pfdev, GPU_L2_PRESENT_LO);
> +	pfdev->features.l2_present |= (u64)gpu_read(pfdev, GPU_L2_PRESENT_HI) << 32;
> +	pfdev->features.nr_core_groups = hweight64(pfdev->features.l2_present);
> +
> +	pfdev->features.stack_present = gpu_read(pfdev, GPU_STACK_PRESENT_LO);
> +	pfdev->features.stack_present |= (u64)gpu_read(pfdev, GPU_STACK_PRESENT_HI) << 32;
> +
> +	gpu_id = gpu_read(pfdev, GPU_ID);
> +	pfdev->features.revision = gpu_id & 0xffff;
> +	pfdev->features.id = gpu_id >> 16;
> +
> +	/* The T60x has an oddball ID value. Fix it up to the standard Midgard
> +	 * format so we (and userspace) don't have to special case it.
> +	 */
> +	if (pfdev->features.id == 0x6956)
> +		pfdev->features.id = 0x0600;
> +
> +	major = (pfdev->features.revision >> 12) & 0xf;
> +	minor = (pfdev->features.revision >> 4) & 0xff;
> +	status = pfdev->features.revision & 0xf;
> +	rev = pfdev->features.revision;
> +
> +	gpu_id = pfdev->features.id;
> +
> +	for (model = gpu_models; model->name; model++) {
> +		int best = -1;
> +
> +		if (!panfrost_model_eq(pfdev, model->id))
> +			continue;
> +
> +		name = model->name;
> +		hw_feat = model->features;
> +		hw_issues |= model->issues;
> +		for (i = 0; i < MAX_HW_REVS; i++) {
> +			if (model->revs[i].revision == rev) {
> +				best = i;
> +				break;
> +			} else if (model->revs[i].revision == (rev & ~0xf))
> +				best = i;
> +		}
> +
> +		if (best >= 0)
> +			hw_issues |= model->revs[best].issues;
> +
> +		break;
> +	}

Might be worth at least a warning if an unknown GPU is detected?

> +
> +	bitmap_from_u64(pfdev->features.hw_features, hw_feat);
> +	bitmap_from_u64(pfdev->features.hw_issues, hw_issues);
> +
> +	dev_info(pfdev->dev, "mali-%s id 0x%x major 0x%x minor 0x%x status 0x%x",
> +		 name, gpu_id, major, minor, status);
> +	dev_info(pfdev->dev, "features: %64pb, issues: %64pb",
> +		 pfdev->features.hw_features,
> +		 pfdev->features.hw_issues);
> +
> +	dev_info(pfdev->dev, "Features: L2:0x%08x Shader:0x%08x Tiler:0x%08x Mem:0x%0x MMU:0x%08x AS:0x%x JS:0x%x",
> +		 gpu_read(pfdev, GPU_L2_FEATURES),
> +		 gpu_read(pfdev, GPU_CORE_FEATURES),
> +		 gpu_read(pfdev, GPU_TILER_FEATURES),
> +		 gpu_read(pfdev, GPU_MEM_FEATURES),
> +		 gpu_read(pfdev, GPU_MMU_FEATURES),
> +		 gpu_read(pfdev, GPU_AS_PRESENT),
> +		 gpu_read(pfdev, GPU_JS_PRESENT));
> +
> +	dev_info(pfdev->dev, "shader_present=0x%0llx l2_present=0x%0llx",
> +		 pfdev->features.shader_present, pfdev->features.l2_present);
> +}
> +
> +void panfrost_gpu_power_on(struct panfrost_device *pfdev)
> +{
> +	int ret;
> +	u32 val;
> +
> +	/* Just turn on everything for now */
> +	gpu_write(pfdev, SHADER_PWRON_LO, pfdev->features.shader_present);
> +	ret = readl_relaxed_poll_timeout(pfdev->iomem + SHADER_READY_LO,
> +		val, val == pfdev->features.shader_present, 100, 1000);
> +
> +	gpu_write(pfdev, TILER_PWRON_LO, pfdev->features.tiler_present);
> +	ret |= readl_relaxed_poll_timeout(pfdev->iomem + TILER_READY_LO,
> +		val, val == pfdev->features.tiler_present, 100, 1000);
> +
> +	gpu_write(pfdev, L2_PWRON_LO, pfdev->features.l2_present);
> +	ret |= readl_relaxed_poll_timeout(pfdev->iomem + L2_READY_LO,
> +		val, val == pfdev->features.l2_present, 100, 1000);
> +
> +	gpu_write(pfdev, STACK_PWRON_LO, pfdev->features.stack_present);
> +	ret |= readl_relaxed_poll_timeout(pfdev->iomem + STACK_READY_LO,
> +		val, val == pfdev->features.stack_present, 100, 1000);
> +
> +	if (ret)
> +		dev_err(pfdev->dev, "error powering up gpu");
> +}

Technically there's a hierarchy here, shaders and tilers depend on
stacks (if present) which depend on the L2, so the ordering is a bit odd
here. However the hardware tries to 'help' by internally triggering the
transition of dependent units. But kbase generally avoids using this
automatic mechanism due to issues in certain circumstances.

> +
> +void panfrost_gpu_power_off(struct panfrost_device *pfdev)
> +{
> +	gpu_write(pfdev, SHADER_PWROFF_LO, 0);
> +	gpu_write(pfdev, TILER_PWROFF_LO, 0);
> +	gpu_write(pfdev, L2_PWROFF_LO, 0);
> +	gpu_write(pfdev, STACK_PWROFF_LO, 0);
> +}
> +
> +int panfrost_gpu_init(struct panfrost_device *pfdev)
> +{
> +	int err, irq;
> +
> +	err = panfrost_gpu_soft_reset(pfdev);
> +	if (err)
> +		return err;
> +
> +	panfrost_gpu_init_features(pfdev);
> +
> +	irq = platform_get_irq_byname(to_platform_device(pfdev->dev), "gpu");
> +	if (irq <= 0)
> +		return -ENODEV;
> +
> +	err = devm_request_irq(pfdev->dev, irq, panfrost_gpu_irq_handler,
> +			       IRQF_SHARED, "gpu", pfdev);
> +	if (err) {
> +		dev_err(pfdev->dev, "failed to request gpu irq");
> +		return err;
> +	}
> +
> +	panfrost_gpu_init_quirks(pfdev);
> +	panfrost_gpu_power_on(pfdev);
> +
> +	return 0;
> +}
> +
> +void panfrost_gpu_fini(struct panfrost_device *pfdev)
> +{
> +	panfrost_gpu_power_off(pfdev);
> +}
> +
> +u32 panfrost_gpu_get_latest_flush_id(struct panfrost_device *pfdev)
> +{
> +	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_FLUSH_REDUCTION))
> +		return gpu_read(pfdev, GPU_LATEST_FLUSH_ID);
> +	return 0;
> +}
> diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.h b/drivers/gpu/drm/panfrost/panfrost_gpu.h
> new file mode 100644
> index 000000000000..4112412087b2
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_gpu.h
> @@ -0,0 +1,19 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
> +/* Copyright 2019 Collabora ltd. */
> +
> +#ifndef __PANFROST_GPU_H__
> +#define __PANFROST_GPU_H__
> +
> +struct panfrost_device;
> +
> +int panfrost_gpu_init(struct panfrost_device *pfdev);
> +void panfrost_gpu_fini(struct panfrost_device *pfdev);
> +
> +u32 panfrost_gpu_get_latest_flush_id(struct panfrost_device *pfdev);
> +
> +int panfrost_gpu_soft_reset(struct panfrost_device *pfdev);
> +void panfrost_gpu_power_on(struct panfrost_device *pfdev);
> +void panfrost_gpu_power_off(struct panfrost_device *pfdev);
> +
> +#endif
> diff --git a/drivers/gpu/drm/panfrost/panfrost_issues.h b/drivers/gpu/drm/panfrost/panfrost_issues.h
> new file mode 100644
> index 000000000000..cec6dcdadb5c
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_issues.h
> @@ -0,0 +1,176 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* (C) COPYRIGHT 2014-2018 ARM Limited. All rights reserved. */
> +/* Copyright 2019 Linaro, Ltd., Rob Herring <robh@kernel.org> */
> +#ifndef __PANFROST_ISSUES_H__
> +#define __PANFROST_ISSUES_H__
> +
> +#include <linux/bitops.h>
> +
> +#include "panfrost_device.h"
> +
> +/*
> + * This is not a complete list of issues, but only the ones the driver needs
> + * to care about.
> + */
> +enum panfrost_hw_issue {
> +	HW_ISSUE_6367,
> +	HW_ISSUE_6787,
> +	HW_ISSUE_8186,
> +	HW_ISSUE_8245,
> +	HW_ISSUE_8316,
> +	HW_ISSUE_8394,
> +	HW_ISSUE_8401,
> +	HW_ISSUE_8408,
> +	HW_ISSUE_8443,
> +	HW_ISSUE_8987,
> +	HW_ISSUE_9435,
> +	HW_ISSUE_9510,
> +	HW_ISSUE_9630,
> +	HW_ISSUE_10327,
> +	HW_ISSUE_10649,
> +	HW_ISSUE_10676,
> +	HW_ISSUE_10797,
> +	HW_ISSUE_10817,
> +	HW_ISSUE_10883,
> +	HW_ISSUE_10959,
> +	HW_ISSUE_10969,
> +	HW_ISSUE_11020,
> +	HW_ISSUE_11024,
> +	HW_ISSUE_11035,
> +	HW_ISSUE_11056,
> +	HW_ISSUE_T76X_3542,
> +	HW_ISSUE_T76X_3953,
> +	HW_ISSUE_TMIX_8463,
> +	GPUCORE_1619,
> +	HW_ISSUE_TMIX_8438,
> +	HW_ISSUE_TGOX_R1_1234,
> +	HW_ISSUE_END
> +};
> +
> +#define hw_issues_all (\
> +	BIT_ULL(HW_ISSUE_9435))
> +
> +#define hw_issues_t600 (\
> +	BIT_ULL(HW_ISSUE_6367) | \
> +	BIT_ULL(HW_ISSUE_6787) | \
> +	BIT_ULL(HW_ISSUE_8408) | \
> +	BIT_ULL(HW_ISSUE_9510) | \
> +	BIT_ULL(HW_ISSUE_10649) | \
> +	BIT_ULL(HW_ISSUE_10676) | \
> +	BIT_ULL(HW_ISSUE_10883) | \
> +	BIT_ULL(HW_ISSUE_11020) | \
> +	BIT_ULL(HW_ISSUE_11035) | \
> +	BIT_ULL(HW_ISSUE_11056) | \
> +	BIT_ULL(HW_ISSUE_TMIX_8438))
> +
> +#define hw_issues_t600_r0p0_15dev0 (\
> +	BIT_ULL(HW_ISSUE_8186) | \
> +	BIT_ULL(HW_ISSUE_8245) | \
> +	BIT_ULL(HW_ISSUE_8316) | \
> +	BIT_ULL(HW_ISSUE_8394) | \
> +	BIT_ULL(HW_ISSUE_8401) | \
> +	BIT_ULL(HW_ISSUE_8443) | \
> +	BIT_ULL(HW_ISSUE_8987) | \
> +	BIT_ULL(HW_ISSUE_9630) | \
> +	BIT_ULL(HW_ISSUE_10969) | \
> +	BIT_ULL(GPUCORE_1619))
> +
> +#define hw_issues_t620 (\
> +	BIT_ULL(HW_ISSUE_10649) | \
> +	BIT_ULL(HW_ISSUE_10883) | \
> +	BIT_ULL(HW_ISSUE_10959) | \
> +	BIT_ULL(HW_ISSUE_11056) | \
> +	BIT_ULL(HW_ISSUE_TMIX_8438))
> +
> +#define hw_issues_t620_r0p1 (\
> +	BIT_ULL(HW_ISSUE_10327) | \
> +	BIT_ULL(HW_ISSUE_10676) | \
> +	BIT_ULL(HW_ISSUE_10817) | \
> +	BIT_ULL(HW_ISSUE_11020) | \
> +	BIT_ULL(HW_ISSUE_11024) | \
> +	BIT_ULL(HW_ISSUE_11035))
> +
> +#define hw_issues_t620_r1p0 (\
> +	BIT_ULL(HW_ISSUE_11020) | \
> +	BIT_ULL(HW_ISSUE_11024))
> +
> +#define hw_issues_t720 (\
> +	BIT_ULL(HW_ISSUE_10649) | \
> +	BIT_ULL(HW_ISSUE_10797) | \
> +	BIT_ULL(HW_ISSUE_10883) | \
> +	BIT_ULL(HW_ISSUE_11056) | \
> +	BIT_ULL(HW_ISSUE_TMIX_8438))
> +
> +#define hw_issues_t760 (\
> +	BIT_ULL(HW_ISSUE_10883) | \
> +	BIT_ULL(HW_ISSUE_T76X_3953) | \
> +	BIT_ULL(HW_ISSUE_TMIX_8438))
> +
> +#define hw_issues_t760_r0p0 (\
> +	BIT_ULL(HW_ISSUE_11020) | \
> +	BIT_ULL(HW_ISSUE_11024) | \
> +	BIT_ULL(HW_ISSUE_T76X_3542))
> +
> +#define hw_issues_t760_r0p1 (\
> +	BIT_ULL(HW_ISSUE_11020) | \
> +	BIT_ULL(HW_ISSUE_11024) | \
> +	BIT_ULL(HW_ISSUE_T76X_3542))
> +
> +#define hw_issues_t760_r0p1_50rel0 (\
> +	BIT_ULL(HW_ISSUE_T76X_3542))
> +
> +#define hw_issues_t760_r0p2 (\
> +	BIT_ULL(HW_ISSUE_11020) | \
> +	BIT_ULL(HW_ISSUE_11024) | \
> +	BIT_ULL(HW_ISSUE_T76X_3542))
> +
> +#define hw_issues_t760_r0p3 (\
> +	BIT_ULL(HW_ISSUE_T76X_3542))
> +
> +#define hw_issues_t820 (\
> +	BIT_ULL(HW_ISSUE_10883) | \
> +	BIT_ULL(HW_ISSUE_T76X_3953) | \
> +	BIT_ULL(HW_ISSUE_TMIX_8438))
> +
> +#define hw_issues_t830 (\
> +	BIT_ULL(HW_ISSUE_10883) | \
> +	BIT_ULL(HW_ISSUE_T76X_3953) | \
> +	BIT_ULL(HW_ISSUE_TMIX_8438))
> +
> +#define hw_issues_t860 (\
> +	BIT_ULL(HW_ISSUE_10883) | \
> +	BIT_ULL(HW_ISSUE_T76X_3953) | \
> +	BIT_ULL(HW_ISSUE_TMIX_8438))
> +
> +#define hw_issues_t880 (\
> +	BIT_ULL(HW_ISSUE_10883) | \
> +	BIT_ULL(HW_ISSUE_T76X_3953) | \
> +	BIT_ULL(HW_ISSUE_TMIX_8438))
> +
> +#define hw_issues_g31 0
> +
> +#define hw_issues_g31_r1p0 (\
> +	BIT_ULL(HW_ISSUE_TGOX_R1_1234))
> +
> +#define hw_issues_g51 0
> +
> +#define hw_issues_g52 0
> +
> +#define hw_issues_g71 (\
> +	BIT_ULL(HW_ISSUE_TMIX_8463) | \
> +	BIT_ULL(HW_ISSUE_TMIX_8438))
> +
> +#define hw_issues_g71_r0p0_05dev0 (\
> +	BIT_ULL(HW_ISSUE_T76X_3953))
> +
> +#define hw_issues_g72 0
> +
> +#define hw_issues_g76 0
> +
> +static inline bool panfrost_has_hw_issue(struct panfrost_device *pfdev,
> +					 enum panfrost_hw_issue issue)
> +{
> +	return test_bit(issue, pfdev->features.hw_issues);
> +}
> +
> +#endif /* __PANFROST_ISSUES_H__ */
> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
> new file mode 100644
> index 000000000000..482e86866b2c
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_job.c
> @@ -0,0 +1,556 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> +/* Copyright 2019 Collabora ltd. */
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/reservation.h>
> +#include <drm/gpu_scheduler.h>
> +#include <drm/panfrost_drm.h>
> +
> +#include "panfrost_device.h"
> +#include "panfrost_devfreq.h"
> +#include "panfrost_job.h"
> +#include "panfrost_features.h"
> +#include "panfrost_issues.h"
> +#include "panfrost_gem.h"
> +#include "panfrost_regs.h"
> +#include "panfrost_gpu.h"
> +#include "panfrost_mmu.h"
> +
> +#define job_write(dev, reg, data) writel(data, dev->iomem + (reg))
> +#define job_read(dev, reg) readl(dev->iomem + (reg))
> +
> +struct panfrost_queue_state {
> +	struct drm_gpu_scheduler sched;
> +
> +	u64 fence_context;
> +	u64 emit_seqno;
> +};
> +
> +struct panfrost_job_slot {
> +	struct panfrost_queue_state queue[NUM_JOB_SLOTS];
> +	spinlock_t job_lock;
> +};
> +
> +static struct panfrost_job *
> +to_panfrost_job(struct drm_sched_job *sched_job)
> +{
> +	return container_of(sched_job, struct panfrost_job, base);
> +}
> +
> +struct panfrost_fence {
> +	struct dma_fence base;
> +	struct drm_device *dev;
> +	/* panfrost seqno for signaled() test */
> +	u64 seqno;
> +	int queue;
> +};
> +
> +static inline struct panfrost_fence *
> +to_panfrost_fence(struct dma_fence *fence)
> +{
> +	return (struct panfrost_fence *)fence;
> +}
> +
> +static const char *panfrost_fence_get_driver_name(struct dma_fence *fence)
> +{
> +	return "panfrost";
> +}
> +
> +static const char *panfrost_fence_get_timeline_name(struct dma_fence *fence)
> +{
> +	struct panfrost_fence *f = to_panfrost_fence(fence);
> +
> +	switch (f->queue) {
> +	case 0:
> +		return "panfrost-js-0";
> +	case 1:
> +		return "panfrost-js-1";
> +	case 2:
> +		return "panfrost-js-2";
> +	default:
> +		return NULL;
> +	}
> +}
> +
> +static const struct dma_fence_ops panfrost_fence_ops = {
> +	.get_driver_name = panfrost_fence_get_driver_name,
> +	.get_timeline_name = panfrost_fence_get_timeline_name,
> +};
> +
> +static struct dma_fence *panfrost_fence_create(struct panfrost_device *pfdev, int js_num)
> +{
> +	struct panfrost_fence *fence;
> +	struct panfrost_job_slot *js = pfdev->js;
> +
> +	fence = kzalloc(sizeof(*fence), GFP_KERNEL);
> +	if (!fence)
> +		return ERR_PTR(-ENOMEM);
> +
> +	fence->dev = pfdev->ddev;
> +	fence->queue = js_num;
> +	fence->seqno = ++js->queue[js_num].emit_seqno;
> +	dma_fence_init(&fence->base, &panfrost_fence_ops, &js->job_lock,
> +		       js->queue[js_num].fence_context, fence->seqno);
> +
> +	return &fence->base;
> +}
> +
> +static int panfrost_job_get_slot(struct panfrost_job *job)
> +{
> +	/* JS0: fragment jobs.
> +	 * JS1: vertex/tiler jobs
> +	 * JS2: compute jobs
> +	 */
> +	if (job->requirements & PANFROST_JD_REQ_FS)
> +		return 0;
> +
> +/* Not exposed to userspace yet */
> +#if 0
> +	if (job->requirements & PANFROST_JD_REQ_ONLY_COMPUTE) {
> +		if ((job->requirements & PANFROST_JD_REQ_CORE_GRP_MASK) &&
> +		    (job->pfdev->features.nr_core_groups == 2))
> +			return 2;
> +		if (panfrost_has_hw_issue(job->pfdev, HW_ISSUE_8987))
> +			return 2;
> +	}
> +#endif
> +	return 1;
> +}
> +
> +static void panfrost_job_write_affinity(struct panfrost_device *pfdev,
> +					u32 requirements,
> +					int js)
> +{
> +	u64 affinity;
> +
> +	/*
> +	 * Use all cores for now.
> +	 * Eventually we may need to support tiler only jobs and h/w with
> +	 * multiple (2) coherent core groups
> +	 */
> +	affinity = pfdev->features.shader_present;
> +
> +	job_write(pfdev, JS_AFFINITY_NEXT_LO(js), affinity & 0xFFFFFFFF);
> +	job_write(pfdev, JS_AFFINITY_NEXT_HI(js), affinity >> 32);
> +}
> +
> +static void panfrost_job_hw_submit(struct panfrost_job *job, int js)
> +{
> +	struct panfrost_device *pfdev = job->pfdev;
> +	unsigned long flags;
> +	u32 cfg;
> +	u64 jc_head = job->jc;
> +	int ret;
> +
> +	panfrost_devfreq_update_utilization(pfdev, js, false);
> +
> +	ret = pm_runtime_get_sync(pfdev->dev);
> +	if (ret < 0)
> +		return;
> +
> +	if (WARN_ON(job_read(pfdev, JS_COMMAND_NEXT(js))))
> +		goto end;
> +
> +	spin_lock_irqsave(&pfdev->hwaccess_lock, flags);
> +
> +	job_write(pfdev, JS_HEAD_NEXT_LO(js), jc_head & 0xFFFFFFFF);
> +	job_write(pfdev, JS_HEAD_NEXT_HI(js), jc_head >> 32);
> +
> +	panfrost_job_write_affinity(pfdev, job->requirements, js);
> +
> +	/* start MMU, medium priority, cache clean/flush on end, clean/flush on
> +	 * start */
> +	// TODO: different address spaces
> +	cfg = JS_CONFIG_THREAD_PRI(8) |
> +		JS_CONFIG_START_FLUSH_CLEAN_INVALIDATE |
> +		JS_CONFIG_END_FLUSH_CLEAN_INVALIDATE;
> +
> +	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_FLUSH_REDUCTION))
> +		cfg |= JS_CONFIG_ENABLE_FLUSH_REDUCTION;
> +
> +	if (panfrost_has_hw_issue(pfdev, HW_ISSUE_10649))
> +		cfg |= JS_CONFIG_START_MMU;

As mentioned in my other email - you might want to include START_MMU
unconditionally.

> +
> +	job_write(pfdev, JS_CONFIG_NEXT(js), cfg);
> +
> +	if (panfrost_has_hw_feature(pfdev, HW_FEATURE_FLUSH_REDUCTION))
> +		job_write(pfdev, JS_FLUSH_ID_NEXT(js), job->flush_id);
> +
> +	/* GO ! */

I think this comment might have survived since the very earliest version
of the Midgard driver! :)

> +	dev_dbg(pfdev->dev, "JS: Submitting atom %p to js[%d] with head=0x%llx",
> +				job, js, jc_head);
> +
> +	job_write(pfdev, JS_COMMAND_NEXT(js), JS_COMMAND_START);
> +
> +	spin_unlock_irqrestore(&pfdev->hwaccess_lock, flags);
> +
> +end:
> +	pm_runtime_mark_last_busy(pfdev->dev);
> +	pm_runtime_put_autosuspend(pfdev->dev);
> +}
> +
> +static void panfrost_acquire_object_fences(struct drm_gem_object **bos,
> +					   int bo_count,
> +					   struct dma_fence **implicit_fences)
> +{
> +	int i;
> +
> +	for (i = 0; i < bo_count; i++)
> +		implicit_fences[i] = reservation_object_get_excl_rcu(bos[i]->resv);
> +}
> +
> +static void panfrost_attach_object_fences(struct drm_gem_object **bos,
> +					  int bo_count,
> +					  struct dma_fence *fence)
> +{
> +	int i;
> +
> +	for (i = 0; i < bo_count; i++)
> +		reservation_object_add_excl_fence(bos[i]->resv, fence);
> +}
> +
> +int panfrost_job_push(struct panfrost_job *job)
> +{
> +	struct panfrost_device *pfdev = job->pfdev;
> +	int slot = panfrost_job_get_slot(job);
> +	struct drm_sched_entity *entity = &job->file_priv->sched_entity[slot];
> +	struct ww_acquire_ctx acquire_ctx;
> +	int ret = 0;
> +
> +	mutex_lock(&pfdev->sched_lock);
> +
> +	ret = drm_gem_lock_reservations(job->bos, job->bo_count,
> +					    &acquire_ctx);
> +	if (ret) {
> +		mutex_unlock(&pfdev->sched_lock);
> +		return ret;
> +	}
> +
> +	ret = drm_sched_job_init(&job->base, entity, NULL);
> +	if (ret) {
> +		mutex_unlock(&pfdev->sched_lock);
> +		goto unlock;
> +	}
> +
> +	job->render_done_fence = dma_fence_get(&job->base.s_fence->finished);
> +
> +	kref_get(&job->refcount); /* put by scheduler job completion */
> +
> +	drm_sched_entity_push_job(&job->base, entity);
> +
> +	mutex_unlock(&pfdev->sched_lock);
> +
> +	panfrost_acquire_object_fences(job->bos, job->bo_count,
> +				       job->implicit_fences);
> +
> +	panfrost_attach_object_fences(job->bos, job->bo_count,
> +				      job->render_done_fence);
> +
> +unlock:
> +	drm_gem_unlock_reservations(job->bos, job->bo_count, &acquire_ctx);
> +
> +	return ret;
> +}
> +
> +static void panfrost_job_cleanup(struct kref *ref)
> +{
> +	struct panfrost_job *job = container_of(ref, struct panfrost_job,
> +						refcount);
> +	unsigned int i;
> +
> +	for (i = 0; i < job->in_fence_count; i++)
> +		dma_fence_put(job->in_fences[i]);

As mentioned above - these arrays could be NULL - either fix the
constructor paths to avoid that, or this cleanup function needs to cope
with it.

> +	kvfree(job->in_fences);
> +
> +	for (i = 0; i < job->bo_count; i++)
> +		dma_fence_put(job->implicit_fences[i]);
> +	kvfree(job->implicit_fences);
> +
> +	dma_fence_put(job->done_fence);
> +	dma_fence_put(job->render_done_fence);
> +
> +	for (i = 0; i < job->bo_count; i++)
> +		drm_gem_object_put_unlocked(job->bos[i]);
> +	kvfree(job->bos);
> +
> +	kfree(job);
> +}
> +
> +void panfrost_job_put(struct panfrost_job *job)
> +{
> +	kref_put(&job->refcount, panfrost_job_cleanup);
> +}
> +
> +static void panfrost_job_free(struct drm_sched_job *sched_job)
> +{
> +	struct panfrost_job *job = to_panfrost_job(sched_job);
> +
> +	drm_sched_job_cleanup(sched_job);
> +
> +	panfrost_job_put(job);
> +}
> +
> +static struct dma_fence *panfrost_job_dependency(struct drm_sched_job *sched_job,
> +						 struct drm_sched_entity *s_entity)
> +{
> +	struct panfrost_job *job = to_panfrost_job(sched_job);
> +	struct dma_fence *fence;
> +	unsigned int i;
> +
> +	/* Explicit fences */
> +	for (i = 0; i < job->in_fence_count; i++) {
> +		if (job->in_fences[i]) {
> +			fence = job->in_fences[i];
> +			job->in_fences[i] = NULL;
> +			return fence;
> +		}
> +	}
> +
> +	/* Implicit fences, max. one per BO */
> +	for (i = 0; i < job->bo_count; i++) {
> +		if (job->implicit_fences[i]) {
> +			fence = job->implicit_fences[i];
> +			job->implicit_fences[i] = NULL;
> +			return fence;
> +		}
> +	}
> +
> +	return NULL;
> +}
> +
> +static struct dma_fence *panfrost_job_run(struct drm_sched_job *sched_job)
> +{
> +	struct panfrost_job *job = to_panfrost_job(sched_job);
> +	struct panfrost_device *pfdev = job->pfdev;
> +	int slot = panfrost_job_get_slot(job);
> +	struct dma_fence *fence = NULL;
> +
> +	if (unlikely(job->base.s_fence->finished.error))
> +		return NULL;
> +
> +	pfdev->jobs[slot] = job;
> +
> +	fence = panfrost_fence_create(pfdev, slot);
> +	if (IS_ERR(fence))
> +		return NULL;
> +
> +	if (job->done_fence)
> +		dma_fence_put(job->done_fence);
> +	job->done_fence = dma_fence_get(fence);
> +
> +	panfrost_job_hw_submit(job, slot);
> +
> +	return fence;
> +}
> +
> +void panfrost_job_enable_interrupts(struct panfrost_device *pfdev)
> +{
> +	int j;
> +	u32 irq_mask = 0;
> +
> +	for (j = 0; j < NUM_JOB_SLOTS; j++) {
> +		irq_mask |= MK_JS_MASK(j);
> +	}
> +
> +	job_write(pfdev, JOB_INT_CLEAR, irq_mask);
> +	job_write(pfdev, JOB_INT_MASK, irq_mask);
> +}
> +
> +static void panfrost_job_timedout(struct drm_sched_job *sched_job)
> +{
> +	struct panfrost_job *job = to_panfrost_job(sched_job);
> +	struct panfrost_device *pfdev = job->pfdev;
> +	int js = panfrost_job_get_slot(job);
> +	int i;
> +
> +	/*
> +	 * If the GPU managed to complete this jobs fence, the timeout is
> +	 * spurious. Bail out.
> +	 */
> +	if (dma_fence_is_signaled(job->done_fence))
> +		return;
> +
> +	dev_err(pfdev->dev, "gpu sched timeout, js=%d, status=0x%x, head=0x%x, tail=0x%x, sched_job=%p",
> +		js,
> +		job_read(pfdev, JS_STATUS(js)),
> +		job_read(pfdev, JS_HEAD_LO(js)),
> +		job_read(pfdev, JS_TAIL_LO(js)),
> +		sched_job);
> +
> +	for (i = 0; i < NUM_JOB_SLOTS; i++)
> +		drm_sched_stop(&pfdev->js->queue[i].sched);
> +
> +	if(sched_job)
> +		drm_sched_increase_karma(sched_job);
> +
> +	//panfrost_core_dump(pfdev);
> +
> +	panfrost_devfreq_update_utilization(pfdev, js, true);
> +	panfrost_gpu_soft_reset(pfdev);
> +
> +	/* TODO: Re-enable all other address spaces */
> +	panfrost_mmu_enable(pfdev, 0);
> +	panfrost_gpu_power_on(pfdev);
> +	panfrost_job_enable_interrupts(pfdev);
> +
> +	for (i = 0; i < NUM_JOB_SLOTS; i++)
> +		drm_sched_resubmit_jobs(&pfdev->js->queue[i].sched);
> +
> +	/* restart scheduler after GPU is usable again */
> +	for (i = 0; i < NUM_JOB_SLOTS; i++)
> +		drm_sched_start(&pfdev->js->queue[i].sched, true);
> +}
> +
> +static const struct drm_sched_backend_ops panfrost_sched_ops = {
> +	.dependency = panfrost_job_dependency,
> +	.run_job = panfrost_job_run,
> +	.timedout_job = panfrost_job_timedout,
> +	.free_job = panfrost_job_free
> +};
> +
> +static irqreturn_t panfrost_job_irq_handler(int irq, void *data)
> +{
> +	struct panfrost_device *pfdev = data;
> +	u32 status = job_read(pfdev, JOB_INT_STAT);
> +	int j;
> +
> +	dev_dbg(pfdev->dev, "jobslot irq status=%x\n", status);
> +
> +	if (!status)
> +		return IRQ_NONE;
> +
> +	pm_runtime_mark_last_busy(pfdev->dev);
> +
> +	for (j = 0; status; j++) {
> +		u32 mask = MK_JS_MASK(j);
> +
> +		if (!(status & mask))
> +			continue;
> +
> +		job_write(pfdev, JOB_INT_CLEAR, mask);
> +
> +		if (status & JOB_INT_MASK_ERR(j)) {
> +			job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_NOP);
> +			job_write(pfdev, JS_COMMAND(j), JS_COMMAND_HARD_STOP_0);

Hard-stopping an already completed job isn't likely to do very much :)
Also you are using the "_0" version which is only valid when "job chain
disambiguation" is present.

I suspect in this case you should also be signalling the fence? At the
moment you rely on the GPU timeout recovering from the fault.

> +
> +			dev_err(pfdev->dev, "js fault, js=%d, status=%s, head=0x%x, tail=0x%x",
> +				j,
> +				panfrost_exception_name(pfdev, job_read(pfdev, JS_STATUS(j))),
> +				job_read(pfdev, JS_HEAD_LO(j)),
> +				job_read(pfdev, JS_TAIL_LO(j)));
> +		}
> +
> +		if (status & JOB_INT_MASK_DONE(j)) {
> +			panfrost_devfreq_update_utilization(pfdev, j, true);
> +			dma_fence_signal(pfdev->jobs[j]->done_fence);
> +		}
> +
> +		status &= ~mask;
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +int panfrost_job_init(struct panfrost_device *pfdev)
> +{
> +	struct panfrost_job_slot *js;
> +	int ret, j, irq;
> +
> +	pfdev->js = js = devm_kzalloc(pfdev->dev, sizeof(*js), GFP_KERNEL);
> +	if (!js)
> +		return -ENOMEM;
> +
> +	spin_lock_init(&js->job_lock);
> +
> +	irq = platform_get_irq_byname(to_platform_device(pfdev->dev), "job");
> +	if (irq <= 0)
> +		return -ENODEV;
> +
> +	ret = devm_request_irq(pfdev->dev, irq, panfrost_job_irq_handler,
> +			       IRQF_SHARED, "job", pfdev);
> +	if (ret) {
> +		dev_err(pfdev->dev, "failed to request job irq");
> +		return ret;
> +	}
> +
> +	for (j = 0; j < NUM_JOB_SLOTS; j++) {
> +		js->queue[j].fence_context = dma_fence_context_alloc(1);
> +
> +		ret = drm_sched_init(&js->queue[j].sched,
> +				     &panfrost_sched_ops,
> +				     1, 0, msecs_to_jiffies(500),
> +				     "pan_js");
> +		if (ret) {
> +			dev_err(pfdev->dev, "Failed to create scheduler: %d.", ret);
> +			goto err_sched;
> +		}
> +	}
> +
> +	panfrost_job_enable_interrupts(pfdev);
> +
> +	return 0;
> +
> +err_sched:
> +	for (j--; j >= 0; j--)
> +		drm_sched_fini(&js->queue[j].sched);
> +
> +	return ret;
> +}
> +
> +void panfrost_job_fini(struct panfrost_device *pfdev)
> +{
> +	struct panfrost_job_slot *js = pfdev->js;
> +	int j;
> +
> +	job_write(pfdev, JOB_INT_MASK, 0);
> +
> +	for (j = 0; j < NUM_JOB_SLOTS; j++)
> +		drm_sched_fini(&js->queue[j].sched);
> +
> +}
> +
> +int panfrost_job_open(struct panfrost_file_priv *panfrost_priv)
> +{
> +	struct panfrost_device *pfdev = panfrost_priv->pfdev;
> +	struct panfrost_job_slot *js = pfdev->js;
> +	struct drm_sched_rq *rq;
> +	int ret, i;
> +
> +	for (i = 0; i < NUM_JOB_SLOTS; i++) {
> +		rq = &js->queue[i].sched.sched_rq[DRM_SCHED_PRIORITY_NORMAL];
> +		ret = drm_sched_entity_init(&panfrost_priv->sched_entity[i], &rq, 1, NULL);
> +		if (WARN_ON(ret))
> +			return ret;
> +	}
> +	return 0;
> +}
> +
> +void panfrost_job_close(struct panfrost_file_priv *panfrost_priv)
> +{
> +	int i;
> +
> +	for (i = 0; i < NUM_JOB_SLOTS; i++)
> +		drm_sched_entity_destroy(&panfrost_priv->sched_entity[i]);
> +}
> +
> +int panfrost_job_is_idle(struct panfrost_device *pfdev)
> +{
> +	struct panfrost_job_slot *js = pfdev->js;
> +	int i;
> +
> +	for (i = 0; i < NUM_JOB_SLOTS; i++) {
> +		/* If there are any jobs in the HW queue, we're not idle */
> +		if (atomic_read(&js->queue[i].sched.hw_rq_count))
> +			return false;
> +
> +		/* Check whether the hardware is idle */
> +		if (job_read(pfdev, JS_STATUS(i)) == JS_STATUS_EVENT_ACTIVE)
> +			return false;
> +	}
> +
> +	return true;
> +}
> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.h b/drivers/gpu/drm/panfrost/panfrost_job.h
> new file mode 100644
> index 000000000000..62454128a792
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_job.h
> @@ -0,0 +1,51 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright 2019 Collabora ltd. */
> +
> +#ifndef __PANFROST_JOB_H__
> +#define __PANFROST_JOB_H__
> +
> +#include <uapi/drm/panfrost_drm.h>
> +#include <drm/gpu_scheduler.h>
> +
> +struct panfrost_device;
> +struct panfrost_gem_object;
> +struct panfrost_file_priv;
> +
> +struct panfrost_job {
> +	struct drm_sched_job base;
> +
> +	struct kref refcount;
> +
> +	struct panfrost_device *pfdev;
> +	struct panfrost_file_priv *file_priv;
> +
> +	/* Optional fences userspace can pass in for the job to depend on. */
> +	struct dma_fence **in_fences;
> +	u32 in_fence_count;
> +
> +	/* Fence to be signaled by IRQ handler when the job is complete. */
> +	struct dma_fence *done_fence;
> +
> +	__u64 jc;
> +	__u32 requirements;
> +	__u32 flush_id;
> +
> +	/* Exclusive fences we have taken from the BOs to wait for */
> +	struct dma_fence **implicit_fences;
> +	struct drm_gem_object **bos;
> +	u32 bo_count;
> +
> +	/* Fence to be signaled by drm-sched once its done with the job */
> +	struct dma_fence *render_done_fence;
> +};
> +
> +int panfrost_job_init(struct panfrost_device *pfdev);
> +void panfrost_job_fini(struct panfrost_device *pfdev);
> +int panfrost_job_open(struct panfrost_file_priv *panfrost_priv);
> +void panfrost_job_close(struct panfrost_file_priv *panfrost_priv);
> +int panfrost_job_push(struct panfrost_job *job);
> +void panfrost_job_put(struct panfrost_job *job);
> +void panfrost_job_enable_interrupts(struct panfrost_device *pfdev);
> +int panfrost_job_is_idle(struct panfrost_device *pfdev);
> +
> +#endif
> diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> new file mode 100644
> index 000000000000..744f5f359386
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> @@ -0,0 +1,366 @@
> +// SPDX-License-Identifier:	GPL-2.0
> +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +#include <linux/io-pgtable.h>
> +#include <linux/iommu.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/sizes.h>
> +
> +#include "panfrost_device.h"
> +#include "panfrost_mmu.h"
> +#include "panfrost_gem.h"
> +#include "panfrost_features.h"
> +#include "panfrost_regs.h"
> +
> +#define mmu_write(dev, reg, data) writel(data, dev->iomem + reg)
> +#define mmu_read(dev, reg) readl(dev->iomem + reg)
> +
> +struct panfrost_mmu {
> +	struct io_pgtable_cfg pgtbl_cfg;
> +	struct io_pgtable_ops *pgtbl_ops;
> +	struct mutex lock;
> +};
> +
> +static int wait_ready(struct panfrost_device *pfdev, u32 as_nr)
> +{
> +	int ret;
> +	u32 val;
> +
> +	/* Wait for the MMU status to indicate there is no active command, in
> +	 * case one is pending. Do not log remaining register accesses. */

I'm not sure this comment about "Do not log" makes sense in the kbase
driver anymore (let alone here) :) We used to have a mechanism for
logging register accesses and this was purposefully excluded to prevent
spamming the log.

> +	ret = readl_relaxed_poll_timeout_atomic(pfdev->iomem + AS_STATUS(as_nr),
> +		val, !(val & AS_STATUS_AS_ACTIVE), 10, 1000);
> +
> +	if (ret)
> +		dev_err(pfdev->dev, "AS_ACTIVE bit stuck\n");
> +
> +	return ret;
> +}
> +
> +static int write_cmd(struct panfrost_device *pfdev, u32 as_nr, u32 cmd)
> +{
> +	int status;
> +
> +	/* write AS_COMMAND when MMU is ready to accept another command */
> +	status = wait_ready(pfdev, as_nr);
> +	if (!status)
> +		mmu_write(pfdev, AS_COMMAND(as_nr), cmd);
> +
> +	return status;
> +}
> +
> +static void lock_region(struct panfrost_device *pfdev, u32 as_nr,
> +			u64 iova, size_t size)
> +{
> +	u8 region_width;
> +	u64 region = iova & PAGE_MASK;
> +	/*
> +	 * fls returns (given the ASSERT above):

But where's the assert? :p

> +	 * 1 .. 32
> +	 *
> +	 * 10 + fls(num_pages)
> +	 * results in the range (11 .. 42)
> +	 */
> +
> +	size = round_up(size, PAGE_SIZE);

I'm not sure it matters, but this will break if called on a (small, i.e.
less than a page) region spanning two pages. "region" will be rounded
down to the page (iova & PAGE_MASK), but size will only be rounded up to
the nearest page. This can miss the start of the second page.

The correct version would be:

size = round_up(size + (iova & PAGE_MASK), PAGE_SIZE);

But I'm not sure anything will attempt to lock a region spanning two
pages like that.

> +
> +	region_width = 10 + fls(size >> PAGE_SHIFT);
> +	if ((size >> PAGE_SHIFT) != (1ul << (region_width - 11))) {
> +		/* not pow2, so must go up to the next pow2 */
> +		region_width += 1;
> +	}
> +	region |= region_width;
> +
> +	/* Lock the region that needs to be updated */
> +	mmu_write(pfdev, AS_LOCKADDR_LO(as_nr), region & 0xFFFFFFFFUL);
> +	mmu_write(pfdev, AS_LOCKADDR_HI(as_nr), (region >> 32) & 0xFFFFFFFFUL);
> +	write_cmd(pfdev, as_nr, AS_COMMAND_LOCK);
> +}
> +
> +
> +static int mmu_hw_do_operation(struct panfrost_device *pfdev, u32 as_nr,
> +		u64 iova, size_t size, u32 op)
> +{
> +	unsigned long flags;
> +	int ret;
> +
> +	spin_lock_irqsave(&pfdev->hwaccess_lock, flags);
> +
> +	if (op != AS_COMMAND_UNLOCK)
> +		lock_region(pfdev, as_nr, iova, size);
> +
> +	/* Run the MMU operation */
> +	write_cmd(pfdev, as_nr, op);
> +
> +	/* Wait for the flush to complete */
> +	ret = wait_ready(pfdev, as_nr);
> +
> +	spin_unlock_irqrestore(&pfdev->hwaccess_lock, flags);
> +
> +	return ret;
> +}
> +
> +void panfrost_mmu_enable(struct panfrost_device *pfdev, u32 as_nr)
> +{
> +	struct io_pgtable_cfg *cfg = &pfdev->mmu->pgtbl_cfg;
> +	u64 transtab = cfg->arm_mali_lpae_cfg.transtab;
> +	u64 memattr = cfg->arm_mali_lpae_cfg.memattr;
> +
> +	mmu_write(pfdev, MMU_INT_CLEAR, ~0);
> +	mmu_write(pfdev, MMU_INT_MASK, ~0);
> +
> +	mmu_write(pfdev, AS_TRANSTAB_LO(as_nr), transtab & 0xffffffffUL);
> +	mmu_write(pfdev, AS_TRANSTAB_HI(as_nr), transtab >> 32);
> +
> +	/* Need to revisit mem attrs.
> +	 * NC is the default, Mali driver is inner WT.
> +	 */
> +	mmu_write(pfdev, AS_MEMATTR_LO(as_nr), memattr & 0xffffffffUL);
> +	mmu_write(pfdev, AS_MEMATTR_HI(as_nr), memattr >> 32);
> +
> +	write_cmd(pfdev, as_nr, AS_COMMAND_UPDATE);
> +}
> +
> +static void mmu_disable(struct panfrost_device *pfdev, u32 as_nr)
> +{
> +	mmu_write(pfdev, AS_TRANSTAB_LO(as_nr), 0);
> +	mmu_write(pfdev, AS_TRANSTAB_HI(as_nr), 0);
> +
> +	mmu_write(pfdev, AS_MEMATTR_LO(as_nr), 0);
> +	mmu_write(pfdev, AS_MEMATTR_HI(as_nr), 0);
> +
> +	write_cmd(pfdev, as_nr, AS_COMMAND_UPDATE);
> +}
> +
> +int panfrost_mmu_map(struct panfrost_gem_object *bo)
> +{
> +	struct drm_gem_object *obj = &bo->base.base;
> +	struct panfrost_device *pfdev = to_panfrost_device(obj->dev);
> +	struct io_pgtable_ops *ops = pfdev->mmu->pgtbl_ops;
> +	u64 iova = bo->node.start << PAGE_SHIFT;
> +	unsigned int count;
> +	struct scatterlist *sgl;
> +	struct sg_table *sgt;
> +	int ret;
> +
> +	sgt = drm_gem_shmem_get_pages_sgt(obj);
> +	if (WARN_ON(IS_ERR(sgt)))
> +		return PTR_ERR(sgt);
> +
> +	ret = pm_runtime_get_sync(pfdev->dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	mutex_lock(&pfdev->mmu->lock);
> +
> +	for_each_sg(sgt->sgl, sgl, sgt->nents, count) {
> +		unsigned long paddr = sg_dma_address(sgl);
> +		size_t len = sg_dma_len(sgl);
> +
> +		while (len) {
> +			dev_dbg(pfdev->dev, "map: iova=%llx, paddr=%lx, len=%zx", iova, paddr, len);
> +			ops->map(ops, iova, paddr, SZ_4K, IOMMU_WRITE | IOMMU_READ);
> +			iova += SZ_4K;
> +			paddr += SZ_4K;
> +			len -= SZ_4K;
> +		}
> +	}
> +
> +	mutex_unlock(&pfdev->mmu->lock);
> +
> +	pm_runtime_mark_last_busy(pfdev->dev);
> +	pm_runtime_put_autosuspend(pfdev->dev);
> +
> +	return 0;
> +}
> +
> +void panfrost_mmu_unmap(struct panfrost_gem_object *bo)
> +{
> +	struct drm_gem_object *obj = &bo->base.base;
> +	struct panfrost_device *pfdev = to_panfrost_device(obj->dev);
> +	struct io_pgtable_ops *ops = pfdev->mmu->pgtbl_ops;
> +	u64 iova = bo->node.start << PAGE_SHIFT;
> +	size_t len = bo->node.size << PAGE_SHIFT;
> +	size_t unmapped_len = 0;
> +	int ret;
> +
> +	ret = pm_runtime_get_sync(pfdev->dev);
> +	if (ret < 0)
> +		return;
> +
> +	mutex_lock(&pfdev->mmu->lock);
> +
> +	while (unmapped_len < len) {
> +		ops->unmap(ops, iova, SZ_4K);
> +		iova += SZ_4K;
> +		unmapped_len += SZ_4K;
> +	}
> +
> +	mutex_unlock(&pfdev->mmu->lock);
> +
> +	pm_runtime_mark_last_busy(pfdev->dev);
> +	pm_runtime_put_autosuspend(pfdev->dev);
> +}
> +
> +static void mmu_tlb_inv_context_s1(void *cookie)
> +{
> +	struct panfrost_device *pfdev = cookie;
> +
> +	mmu_hw_do_operation(pfdev, 0, 0, ~0UL, AS_COMMAND_FLUSH_MEM);
> +}
> +
> +static void mmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
> +				     size_t granule, bool leaf, void *cookie)
> +{
> +	struct panfrost_device *pfdev = cookie;
> +
> +	dev_dbg(pfdev->dev, "inv_range: iova=%lx, size=%zx, granule=%zx, leaf=%d",
> +		iova, size, granule, leaf);
> +	mmu_hw_do_operation(pfdev, 0, iova, size, AS_COMMAND_FLUSH_PT);
> +}
> +
> +static void mmu_tlb_sync_context(void *cookie)
> +{
> +	//struct panfrost_device *pfdev = cookie;
> +	// Wait 1000 GPU cycles!?

To be fair only for BASE_HW_ISSUE_6367/T60X - but yes it's not a
pleasant workaround. There's no way on that hardware to reliably drain
the write buffer other than waiting.

> +}
> +
> +static const struct iommu_gather_ops mmu_tlb_ops = {
> +	.tlb_flush_all	= mmu_tlb_inv_context_s1,
> +	.tlb_add_flush	= mmu_tlb_inv_range_nosync,
> +	.tlb_sync	= mmu_tlb_sync_context,
> +};
> +
> +static const char *access_type_name(struct panfrost_device *pfdev,
> +		u32 fault_status)
> +{
> +	switch (fault_status & AS_FAULTSTATUS_ACCESS_TYPE_MASK) {
> +	case AS_FAULTSTATUS_ACCESS_TYPE_ATOMIC:
> +		if (panfrost_has_hw_feature(pfdev, HW_FEATURE_AARCH64_MMU))
> +			return "ATOMIC";
> +		else
> +			return "UNKNOWN";
> +	case AS_FAULTSTATUS_ACCESS_TYPE_READ:
> +		return "READ";
> +	case AS_FAULTSTATUS_ACCESS_TYPE_WRITE:
> +		return "WRITE";
> +	case AS_FAULTSTATUS_ACCESS_TYPE_EX:
> +		return "EXECUTE";
> +	default:
> +		WARN_ON(1);
> +		return NULL;
> +	}
> +}
> +
> +static irqreturn_t panfrost_mmu_irq_handler(int irq, void *data)
> +{
> +	struct panfrost_device *pfdev = data;
> +	u32 status = mmu_read(pfdev, MMU_INT_STAT);
> +	int i;
> +
> +	if (!status)
> +		return IRQ_NONE;
> +
> +	dev_err(pfdev->dev, "mmu irq status=%x\n", status);
> +
> +	for (i = 0; status; i++) {
> +		u32 mask = BIT(i) | BIT(i + 16);
> +		u64 addr;
> +		u32 fault_status;
> +		u32 exception_type;
> +		u32 access_type;
> +		u32 source_id;
> +
> +		if (!(status & mask))
> +			continue;
> +
> +		fault_status = mmu_read(pfdev, AS_FAULTSTATUS(i));
> +		addr = mmu_read(pfdev, AS_FAULTADDRESS_LO(i));
> +		addr |= (u64)mmu_read(pfdev, AS_FAULTADDRESS_HI(i)) << 32;
> +
> +		/* decode the fault status */
> +		exception_type = fault_status & 0xFF;
> +		access_type = (fault_status >> 8) & 0x3;
> +		source_id = (fault_status >> 16);
> +
> +		/* terminal fault, print info about the fault */
> +		dev_err(pfdev->dev,
> +			"Unhandled Page fault in AS%d at VA 0x%016llX\n"
> +			"Reason: %s\n"
> +			"raw fault status: 0x%X\n"
> +			"decoded fault status: %s\n"
> +			"exception type 0x%X: %s\n"
> +			"access type 0x%X: %s\n"
> +			"source id 0x%X\n",
> +			i, addr,
> +			"TODO",
> +			fault_status,
> +			(fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
> +			exception_type, panfrost_exception_name(pfdev, exception_type),
> +			access_type, access_type_name(pfdev, fault_status),
> +			source_id);
> +
> +		mmu_write(pfdev, MMU_INT_CLEAR, mask);

To fully handle the fault you will need to issue an MMU command (i.e.
call mmu_hw_do_operation()) - obviously after doing something to fix the
cause (e.g. mapping a page or switching the GPU to UNMAPPED mode to kill
off the job). Otherwise you may see that the GPU hangs. Although in
practice at this stage of the driver the generic timeout is probably the
simplest way of handling an MMU fault.

> +
> +		status &= ~mask;
> +	}
> +
> +	return IRQ_HANDLED;
> +};
> +
> +int panfrost_mmu_init(struct panfrost_device *pfdev)
> +{
> +	struct io_pgtable_ops *pgtbl_ops;
> +	int err, irq;
> +
> +	pfdev->mmu = devm_kzalloc(pfdev->dev, sizeof(*pfdev->mmu), GFP_KERNEL);
> +	if (!pfdev->mmu)
> +		return -ENOMEM;
> +
> +	mutex_init(&pfdev->mmu->lock);
> +
> +	irq = platform_get_irq_byname(to_platform_device(pfdev->dev), "mmu");
> +	if (irq <= 0)
> +		return -ENODEV;
> +
> +	err = devm_request_irq(pfdev->dev, irq, panfrost_mmu_irq_handler,
> +			       IRQF_SHARED, "mmu", pfdev);
> +
> +	if (err) {
> +		dev_err(pfdev->dev, "failed to request mmu irq");
> +		return err;
> +	}
> +	mmu_write(pfdev, MMU_INT_CLEAR, ~0);
> +	mmu_write(pfdev, MMU_INT_MASK, ~0);
> +
> +	pfdev->mmu->pgtbl_cfg = (struct io_pgtable_cfg) {
> +		.pgsize_bitmap	= SZ_4K, // | SZ_2M | SZ_1G),
> +		.ias		= 48,
> +		.oas		= 40,	/* Should come from dma mask? */
> +		.tlb		= &mmu_tlb_ops,
> +		.iommu_dev	= pfdev->dev,
> +	};
> +
> +	pgtbl_ops = alloc_io_pgtable_ops(ARM_MALI_LPAE, &pfdev->mmu->pgtbl_cfg,
> +					 pfdev);
> +	if (!pgtbl_ops)
> +		return -ENOMEM;
> +
> +	pfdev->mmu->pgtbl_ops = pgtbl_ops;
> +
> +	panfrost_mmu_enable(pfdev, 0);
> +
> +	return 0;
> +}
> +
> +void panfrost_mmu_fini(struct panfrost_device *pfdev)
> +{
> +	mmu_write(pfdev, MMU_INT_MASK, 0);
> +	mmu_disable(pfdev, 0);
> +
> +	free_io_pgtable_ops(pfdev->mmu->pgtbl_ops);
> +}
> diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.h b/drivers/gpu/drm/panfrost/panfrost_mmu.h
> new file mode 100644
> index 000000000000..f5878d86a5ce
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.h
> @@ -0,0 +1,17 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> +
> +#ifndef __PANFROST_MMU_H__
> +#define __PANFROST_MMU_H__
> +
> +struct panfrost_gem_object;
> +
> +int panfrost_mmu_map(struct panfrost_gem_object *bo);
> +void panfrost_mmu_unmap(struct panfrost_gem_object *bo);
> +
> +int panfrost_mmu_init(struct panfrost_device *pfdev);
> +void panfrost_mmu_fini(struct panfrost_device *pfdev);
> +
> +void panfrost_mmu_enable(struct panfrost_device *pfdev, u32 as_nr);
> +
> +#endif
> diff --git a/drivers/gpu/drm/panfrost/panfrost_regs.h b/drivers/gpu/drm/panfrost/panfrost_regs.h
> new file mode 100644
> index 000000000000..578c5fc2188b
> --- /dev/null
> +++ b/drivers/gpu/drm/panfrost/panfrost_regs.h
> @@ -0,0 +1,298 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright 2018 Marty E. Plummer <hanetzer@startmail.com> */
> +/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
> +/*
> + * Register definitions based on mali_midg_regmap.h
> + * (C) COPYRIGHT 2010-2018 ARM Limited. All rights reserved.
> + */
> +#ifndef __PANFROST_REGS_H__
> +#define __PANFROST_REGS_H__
> +
> +#define GPU_ID				0x00
> +#define GPU_L2_FEATURES			0x004	/* (RO) Level 2 cache features */
> +#define GPU_CORE_FEATURES		0x008	/* (RO) Shader Core Features */
> +#define GPU_TILER_FEATURES		0x00C	/* (RO) Tiler Features */
> +#define GPU_MEM_FEATURES		0x010	/* (RO) Memory system features */
> +#define   GROUPS_L2_COHERENT		BIT(0)	/* Cores groups are l2 coherent */
> +
> +#define GPU_MMU_FEATURES		0x014	/* (RO) MMU features */
> +#define GPU_AS_PRESENT			0x018	/* (RO) Address space slots present */
> +#define GPU_JS_PRESENT			0x01C	/* (RO) Job slots present */
> +
> +#define GPU_INT_RAWSTAT			0x20
> +#define GPU_INT_CLEAR			0x24
> +#define GPU_INT_MASK			0x28
> +#define GPU_INT_STAT			0x2c
> +#define   GPU_IRQ_FAULT			BIT(0)
> +#define   GPU_IRQ_MULTIPLE_FAULT	BIT(7)
> +#define   GPU_IRQ_RESET_COMPLETED	BIT(8)
> +#define   GPU_IRQ_POWER_CHANGED		BIT(9)
> +#define   GPU_IRQ_POWER_CHANGED_ALL	BIT(10)
> +#define   GPU_IRQ_PERFCNT_SAMPLE_COMPLETED BIT(16)
> +#define   GPU_IRQ_CLEAN_CACHES_COMPLETED BIT(17)
> +#define   GPU_IRQ_MASK_ALL			 \
> +	  (GPU_IRQ_FAULT			|\
> +	   GPU_IRQ_MULTIPLE_FAULT		|\
> +	   GPU_IRQ_RESET_COMPLETED		|\
> +	   GPU_IRQ_POWER_CHANGED		|\
> +	   GPU_IRQ_POWER_CHANGED_ALL		|\
> +	   GPU_IRQ_PERFCNT_SAMPLE_COMPLETED	|\
> +	   GPU_IRQ_CLEAN_CACHES_COMPLETED)
> +#define GPU_IRQ_MASK_ERROR	   		\
> +	(					\
> +	 GPU_IRQ_FAULT				|\
> +	 GPU_IRQ_MULTIPLE_FAULT)
> +#define GPU_CMD				0x30
> +#define   GPU_CMD_SOFT_RESET		0x01
> +#define GPU_STATUS			0x34
> +#define GPU_LATEST_FLUSH_ID		0x38
> +#define GPU_FAULT_STATUS		0x3C
> +#define GPU_FAULT_ADDRESS_LO		0x40
> +#define GPU_FAULT_ADDRESS_HI		0x44
> +
> +#define GPU_THREAD_MAX_THREADS		0x0A0	/* (RO) Maximum number of threads per core */
> +#define GPU_THREAD_MAX_WORKGROUP_SIZE	0x0A4	/* (RO) Maximum workgroup size */
> +#define GPU_THREAD_MAX_BARRIER_SIZE	0x0A8	/* (RO) Maximum threads waiting at a barrier */
> +#define GPU_THREAD_FEATURES		0x0AC	/* (RO) Thread features */
> +#define GPU_THREAD_TLS_ALLOC		0x310   /* (RO) Number of threads per core that
> +						 * TLS must be allocated for */
> +
> +#define GPU_TEXTURE_FEATURES(n)		(0x0B0 + ((n) * 4))
> +#define GPU_JS_FEATURES(n)		(0x0C0 + ((n) * 4))
> +
> +#define GPU_SHADER_PRESENT_LO		0x100	/* (RO) Shader core present bitmap, low word */
> +#define GPU_SHADER_PRESENT_HI		0x104	/* (RO) Shader core present bitmap, high word */
> +#define GPU_TILER_PRESENT_LO		0x110	/* (RO) Tiler core present bitmap, low word */
> +#define GPU_TILER_PRESENT_HI		0x114	/* (RO) Tiler core present bitmap, high word */
> +
> +#define GPU_L2_PRESENT_LO		0x120	/* (RO) Level 2 cache present bitmap, low word */
> +#define GPU_L2_PRESENT_HI		0x124	/* (RO) Level 2 cache present bitmap, high word */
> +
> +#define GPU_COHERENCY_FEATURES		0x300	/* (RO) Coherency features present */
> +#define   COHERENCY_ACE_LITE		BIT(0)
> +#define   COHERENCY_ACE			BIT(1)
> +
> +#define GPU_STACK_PRESENT_LO		0xE00   /* (RO) Core stack present bitmap, low word */
> +#define GPU_STACK_PRESENT_HI		0xE04   /* (RO) Core stack present bitmap, high word */
> +
> +#define SHADER_READY_LO			0x140	/* (RO) Shader core ready bitmap, low word */
> +#define SHADER_READY_HI			0x144	/* (RO) Shader core ready bitmap, high word */
> +
> +#define TILER_READY_LO			0x150	/* (RO) Tiler core ready bitmap, low word */
> +#define TILER_READY_HI			0x154	/* (RO) Tiler core ready bitmap, high word */
> +
> +#define L2_READY_LO			0x160	/* (RO) Level 2 cache ready bitmap, low word */
> +#define L2_READY_HI			0x164	/* (RO) Level 2 cache ready bitmap, high word */
> +
> +#define STACK_READY_LO			0xE10   /* (RO) Core stack ready bitmap, low word */
> +#define STACK_READY_HI			0xE14   /* (RO) Core stack ready bitmap, high word */
> +
> +
> +#define SHADER_PWRON_LO			0x180	/* (WO) Shader core power on bitmap, low word */
> +#define SHADER_PWRON_HI			0x184	/* (WO) Shader core power on bitmap, high word */
> +
> +#define TILER_PWRON_LO			0x190	/* (WO) Tiler core power on bitmap, low word */
> +#define TILER_PWRON_HI			0x194	/* (WO) Tiler core power on bitmap, high word */
> +
> +#define L2_PWRON_LO			0x1A0	/* (WO) Level 2 cache power on bitmap, low word */
> +#define L2_PWRON_HI			0x1A4	/* (WO) Level 2 cache power on bitmap, high word */
> +
> +#define STACK_PWRON_LO			0xE20   /* (RO) Core stack power on bitmap, low word */
> +#define STACK_PWRON_HI			0xE24   /* (RO) Core stack power on bitmap, high word */
> +
> +
> +#define SHADER_PWROFF_LO		0x1C0	/* (WO) Shader core power off bitmap, low word */
> +#define SHADER_PWROFF_HI		0x1C4	/* (WO) Shader core power off bitmap, high word */
> +
> +#define TILER_PWROFF_LO			0x1D0	/* (WO) Tiler core power off bitmap, low word */
> +#define TILER_PWROFF_HI			0x1D4	/* (WO) Tiler core power off bitmap, high word */
> +
> +#define L2_PWROFF_LO			0x1E0	/* (WO) Level 2 cache power off bitmap, low word */
> +#define L2_PWROFF_HI			0x1E4	/* (WO) Level 2 cache power off bitmap, high word */
> +
> +#define STACK_PWROFF_LO			0xE30   /* (RO) Core stack power off bitmap, low word */
> +#define STACK_PWROFF_HI			0xE34   /* (RO) Core stack power off bitmap, high word */
> +
> +
> +#define SHADER_PWRTRANS_LO		0x200	/* (RO) Shader core power transition bitmap, low word */
> +#define SHADER_PWRTRANS_HI		0x204	/* (RO) Shader core power transition bitmap, high word */
> +
> +#define TILER_PWRTRANS_LO		0x210	/* (RO) Tiler core power transition bitmap, low word */
> +#define TILER_PWRTRANS_HI		0x214	/* (RO) Tiler core power transition bitmap, high word */
> +
> +#define L2_PWRTRANS_LO			0x220	/* (RO) Level 2 cache power transition bitmap, low word */
> +#define L2_PWRTRANS_HI			0x224	/* (RO) Level 2 cache power transition bitmap, high word */
> +
> +#define STACK_PWRTRANS_LO		0xE40   /* (RO) Core stack power transition bitmap, low word */
> +#define STACK_PWRTRANS_HI		0xE44   /* (RO) Core stack power transition bitmap, high word */
> +
> +
> +#define SHADER_PWRACTIVE_LO		0x240	/* (RO) Shader core active bitmap, low word */
> +#define SHADER_PWRACTIVE_HI		0x244	/* (RO) Shader core active bitmap, high word */
> +
> +#define TILER_PWRACTIVE_LO		0x250	/* (RO) Tiler core active bitmap, low word */
> +#define TILER_PWRACTIVE_HI		0x254	/* (RO) Tiler core active bitmap, high word */
> +
> +#define L2_PWRACTIVE_LO			0x260	/* (RO) Level 2 cache active bitmap, low word */
> +#define L2_PWRACTIVE_HI			0x264	/* (RO) Level 2 cache active bitmap, high word */
> +
> +#define GPU_JM_CONFIG			0xF00   /* (RW) Job Manager configuration register (Implementation specific register) */
> +#define GPU_SHADER_CONFIG		0xF04	/* (RW) Shader core configuration settings (Implementation specific register) */
> +#define GPU_TILER_CONFIG		0xF08   /* (RW) Tiler core configuration settings (Implementation specific register) */
> +#define GPU_L2_MMU_CONFIG		0xF0C	/* (RW) Configuration of the L2 cache and MMU (Implementation specific register) */
> +
> +/* L2_MMU_CONFIG register */
> +#define L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY_SHIFT	23
> +#define L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY		(0x1 << L2_MMU_CONFIG_ALLOW_SNOOP_DISPARITY_SHIFT)
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT	24
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS		(0x3 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_OCTANT	(0x1 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_QUARTER	(0x2 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_HALF		(0x3 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
> +
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT	26
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES		(0x3 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_OCTANT	(0x1 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_QUARTER	(0x2 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
> +#define L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_HALF	(0x3 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
> +
> +#define L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_READS_SHIFT	12
> +#define L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_READS		(0x7 << L2_MMU_CONFIG_LIMIT_EXTERNAL_READS_SHIFT)
> +
> +#define L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_WRITES_SHIFT	15
> +#define L2_MMU_CONFIG_3BIT_LIMIT_EXTERNAL_WRITES	(0x7 << L2_MMU_CONFIG_LIMIT_EXTERNAL_WRITES_SHIFT)
> +
> +/* SHADER_CONFIG register */
> +#define SC_ALT_COUNTERS			BIT(3)
> +#define SC_OVERRIDE_FWD_PIXEL_KILL	BIT(4)
> +#define SC_SDC_DISABLE_OQ_DISCARD	BIT(6)
> +#define SC_LS_ALLOW_ATTR_TYPES		BIT(16)
> +#define SC_LS_PAUSEBUFFER_DISABLE	BIT(16)
> +#define SC_TLS_HASH_ENABLE		BIT(17)
> +#define SC_LS_ATTR_CHECK_DISABLE	BIT(18)
> +#define SC_ENABLE_TEXGRD_FLAGS		BIT(25)
> +/* End SHADER_CONFIG register */
> +
> +/* TILER_CONFIG register */
> +#define TC_CLOCK_GATE_OVERRIDE		BIT(0)
> +
> +/* JM_CONFIG register */
> +#define JM_TIMESTAMP_OVERRIDE		BIT(0)
> +#define JM_CLOCK_GATE_OVERRIDE		BIT(1)
> +#define JM_JOB_THROTTLE_ENABLE		BIT(2)
> +#define JM_JOB_THROTTLE_LIMIT_SHIFT	3
> +#define JM_MAX_JOB_THROTTLE_LIMIT	0x3F
> +#define JM_FORCE_COHERENCY_FEATURES_SHIFT 2
> +#define JM_IDVS_GROUP_SIZE_SHIFT	16
> +#define JM_MAX_IDVS_GROUP_SIZE		0x3F
> +
> +
> +/* Job Control regs */
> +#define JOB_INT_RAWSTAT			0x1000
> +#define JOB_INT_CLEAR			0x1004
> +#define JOB_INT_MASK			0x1008
> +#define JOB_INT_STAT			0x100c
> +#define JOB_INT_JS_STATE		0x1010
> +#define JOB_INT_THROTTLE		0x1014
> +
> +#define MK_JS_MASK(j)			(0x10001 << (j))
> +#define JOB_INT_MASK_ERR(j)		BIT((j) + 16)
> +#define JOB_INT_MASK_DONE(j)		BIT(j)
> +
> +#define JS_BASE				0x1800
> +#define JS_HEAD_LO(n)			(JS_BASE + ((n) * 0x80) + 0x00)
> +#define JS_HEAD_HI(n)			(JS_BASE + ((n) * 0x80) + 0x04)
> +#define JS_TAIL_LO(n)			(JS_BASE + ((n) * 0x80) + 0x08)
> +#define JS_TAIL_HI(n)			(JS_BASE + ((n) * 0x80) + 0x0c)
> +#define JS_AFFINITY_LO(n)		(JS_BASE + ((n) * 0x80) + 0x10)
> +#define JS_AFFINITY_HI(n)		(JS_BASE + ((n) * 0x80) + 0x14)
> +#define JS_CONFIG(n)			(JS_BASE + ((n) * 0x80) + 0x18)
> +#define JS_XAFFINITY(n)			(JS_BASE + ((n) * 0x80) + 0x1c)
> +#define JS_COMMAND(n)			(JS_BASE + ((n) * 0x80) + 0x20)
> +#define JS_STATUS(n)			(JS_BASE + ((n) * 0x80) + 0x24)
> +#define JS_HEAD_NEXT_LO(n)		(JS_BASE + ((n) * 0x80) + 0x40)
> +#define JS_HEAD_NEXT_HI(n)		(JS_BASE + ((n) * 0x80) + 0x44)
> +#define JS_AFFINITY_NEXT_LO(n)		(JS_BASE + ((n) * 0x80) + 0x50)
> +#define JS_AFFINITY_NEXT_HI(n)		(JS_BASE + ((n) * 0x80) + 0x54)
> +#define JS_CONFIG_NEXT(n)		(JS_BASE + ((n) * 0x80) + 0x58)
> +#define JS_COMMAND_NEXT(n)		(JS_BASE + ((n) * 0x80) + 0x60)
> +#define JS_FLUSH_ID_NEXT(n)		(JS_BASE + ((n) * 0x80) + 0x70)
> +
> +/* Possible values of JS_CONFIG and JS_CONFIG_NEXT registers */
> +#define JS_CONFIG_START_FLUSH_CLEAN		BIT(8)
> +#define JS_CONFIG_START_FLUSH_CLEAN_INVALIDATE	(3u << 8)
> +#define JS_CONFIG_START_MMU			BIT(10)
> +#define JS_CONFIG_JOB_CHAIN_FLAG		BIT(11)
> +#define JS_CONFIG_END_FLUSH_CLEAN		BIT(12)
> +#define JS_CONFIG_END_FLUSH_CLEAN_INVALIDATE	(3u << 12)
> +#define JS_CONFIG_ENABLE_FLUSH_REDUCTION	BIT(14)
> +#define JS_CONFIG_DISABLE_DESCRIPTOR_WR_BK	BIT(15)
> +#define JS_CONFIG_THREAD_PRI(n)			((n) << 16)
> +
> +#define JS_COMMAND_NOP			0x00
> +#define JS_COMMAND_START		0x01
> +#define JS_COMMAND_SOFT_STOP		0x02	/* Gently stop processing a job chain */
> +#define JS_COMMAND_HARD_STOP		0x03	/* Rudely stop processing a job chain */
> +#define JS_COMMAND_SOFT_STOP_0		0x04	/* Execute SOFT_STOP if JOB_CHAIN_FLAG is 0 */
> +#define JS_COMMAND_HARD_STOP_0		0x05	/* Execute HARD_STOP if JOB_CHAIN_FLAG is 0 */
> +#define JS_COMMAND_SOFT_STOP_1		0x06	/* Execute SOFT_STOP if JOB_CHAIN_FLAG is 1 */
> +#define JS_COMMAND_HARD_STOP_1		0x07	/* Execute HARD_STOP if JOB_CHAIN_FLAG is 1 */
> +
> +#define JS_STATUS_EVENT_ACTIVE		0x08
> +
> +
> +/* MMU regs */
> +#define MMU_INT_RAWSTAT			0x2000
> +#define MMU_INT_CLEAR			0x2004
> +#define MMU_INT_MASK			0x2008
> +#define MMU_INT_STAT			0x200c
> +
> +/* AS_COMMAND register commands */
> +#define AS_COMMAND_NOP			0x00	/* NOP Operation */
> +#define AS_COMMAND_UPDATE		0x01	/* Broadcasts the values in AS_TRANSTAB and ASn_MEMATTR to all MMUs */
> +#define AS_COMMAND_LOCK			0x02	/* Issue a lock region command to all MMUs */
> +#define AS_COMMAND_UNLOCK		0x03	/* Issue a flush region command to all MMUs */
> +#define AS_COMMAND_FLUSH		0x04	/* Flush all L2 caches then issue a flush region command to all MMUs
> +						   (deprecated - only for use with T60x) */
> +#define AS_COMMAND_FLUSH_PT		0x04	/* Flush all L2 caches then issue a flush region command to all MMUs */
> +#define AS_COMMAND_FLUSH_MEM		0x05	/* Wait for memory accesses to complete, flush all the L1s cache then
> +						   flush all L2 caches then issue a flush region command to all MMUs */
> +
> +#define MMU_AS(as)			(0x2400 + ((as) << 6))
> +
> +#define AS_TRANSTAB_LO(as)		(MMU_AS(as) + 0x00) /* (RW) Translation Table Base Address for address space n, low word */
> +#define AS_TRANSTAB_HI(as)		(MMU_AS(as) + 0x04) /* (RW) Translation Table Base Address for address space n, high word */
> +#define AS_MEMATTR_LO(as)		(MMU_AS(as) + 0x08) /* (RW) Memory attributes for address space n, low word. */
> +#define AS_MEMATTR_HI(as)		(MMU_AS(as) + 0x0C) /* (RW) Memory attributes for address space n, high word. */
> +#define AS_LOCKADDR_LO(as)		(MMU_AS(as) + 0x10) /* (RW) Lock region address for address space n, low word */
> +#define AS_LOCKADDR_HI(as)		(MMU_AS(as) + 0x14) /* (RW) Lock region address for address space n, high word */
> +#define AS_COMMAND(as)			(MMU_AS(as) + 0x18) /* (WO) MMU command register for address space n */
> +#define AS_FAULTSTATUS(as)		(MMU_AS(as) + 0x1C) /* (RO) MMU fault status register for address space n */
> +#define AS_FAULTADDRESS_LO(as)		(MMU_AS(as) + 0x20) /* (RO) Fault Address for address space n, low word */
> +#define AS_FAULTADDRESS_HI(as)		(MMU_AS(as) + 0x24) /* (RO) Fault Address for address space n, high word */
> +#define AS_STATUS(as)			(MMU_AS(as) + 0x28) /* (RO) Status flags for address space n */
> +/* Additional Bifrost AS regsiters */
> +#define AS_TRANSCFG_LO(as)		(MMU_AS(as) + 0x30) /* (RW) Translation table configuration for address space n, low word */
> +#define AS_TRANSCFG_HI(as)		(MMU_AS(as) + 0x34) /* (RW) Translation table configuration for address space n, high word */
> +#define AS_FAULTEXTRA_LO(as)		(MMU_AS(as) + 0x38) /* (RO) Secondary fault address for address space n, low word */
> +#define AS_FAULTEXTRA_HI(as)		(MMU_AS(as) + 0x3C) /* (RO) Secondary fault address for address space n, high word */
> +
> +/*
> + * Begin LPAE MMU TRANSTAB register values
> + */
> +#define AS_TRANSTAB_LPAE_ADDR_SPACE_MASK	0xfffffffffffff000
> +#define AS_TRANSTAB_LPAE_ADRMODE_IDENTITY	0x2
> +#define AS_TRANSTAB_LPAE_ADRMODE_TABLE		0x3
> +#define AS_TRANSTAB_LPAE_ADRMODE_MASK		0x3
> +#define AS_TRANSTAB_LPAE_READ_INNER		BIT(2)
> +#define AS_TRANSTAB_LPAE_SHARE_OUTER		BIT(4)
> +
> +#define AS_STATUS_AS_ACTIVE			0x01
> +
> +#define AS_FAULTSTATUS_ACCESS_TYPE_MASK		(0x3 << 8)
> +#define AS_FAULTSTATUS_ACCESS_TYPE_ATOMIC	(0x0 << 8)
> +#define AS_FAULTSTATUS_ACCESS_TYPE_EX		(0x1 << 8)
> +#define AS_FAULTSTATUS_ACCESS_TYPE_READ		(0x2 << 8)
> +#define AS_FAULTSTATUS_ACCESS_TYPE_WRITE	(0x3 << 8)
> +
> +#endif
> diff --git a/include/uapi/drm/panfrost_drm.h b/include/uapi/drm/panfrost_drm.h
> new file mode 100644
> index 000000000000..508b9621d9db
> --- /dev/null
> +++ b/include/uapi/drm/panfrost_drm.h
> @@ -0,0 +1,140 @@
> +/* SPDX-License-Identifier: MIT */
> +/*
> + * Copyright © 2014-2018 Broadcom
> + * Copyright © 2019 Collabora ltd.
> + */
> +#ifndef _PANFROST_DRM_H_
> +#define _PANFROST_DRM_H_
> +
> +#include "drm.h"
> +
> +#if defined(__cplusplus)
> +extern "C" {
> +#endif
> +
> +#define DRM_PANFROST_SUBMIT			0x00
> +#define DRM_PANFROST_WAIT_BO			0x01
> +#define DRM_PANFROST_CREATE_BO			0x02
> +#define DRM_PANFROST_MMAP_BO			0x03
> +#define DRM_PANFROST_GET_PARAM			0x04
> +#define DRM_PANFROST_GET_BO_OFFSET		0x05
> +
> +#define DRM_IOCTL_PANFROST_SUBMIT		DRM_IOW(DRM_COMMAND_BASE + DRM_PANFROST_SUBMIT, struct drm_panfrost_submit)
> +#define DRM_IOCTL_PANFROST_WAIT_BO		DRM_IOW(DRM_COMMAND_BASE + DRM_PANFROST_WAIT_BO, struct drm_panfrost_wait_bo)
> +#define DRM_IOCTL_PANFROST_CREATE_BO		DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_CREATE_BO, struct drm_panfrost_create_bo)
> +#define DRM_IOCTL_PANFROST_MMAP_BO		DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_MMAP_BO, struct drm_panfrost_mmap_bo)
> +#define DRM_IOCTL_PANFROST_GET_PARAM		DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_GET_PARAM, struct drm_panfrost_get_param)
> +#define DRM_IOCTL_PANFROST_GET_BO_OFFSET	DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_GET_BO_OFFSET, struct drm_panfrost_get_bo_offset)
> +
> +#define PANFROST_JD_REQ_FS (1 << 0)
> +/**
> + * struct drm_panfrost_submit - ioctl argument for submitting commands to the 3D
> + * engine.
> + *
> + * This asks the kernel to have the GPU execute a render command list.
> + */
> +struct drm_panfrost_submit {
> +
> +	/** Address to GPU mapping of job descriptor */
> +	__u64 jc;
> +
> +	/** An optional array of sync objects to wait on before starting this job. */
> +	__u64 in_syncs;
> +
> +	/** Number of sync objects to wait on before starting this job. */
> +	__u32 in_sync_count;
> +
> +	/** An optional sync object to place the completion fence in. */
> +	__u32 out_sync;
> +
> +	/** Pointer to a u32 array of the BOs that are referenced by the job. */
> +	__u64 bo_handles;
> +
> +	/** Number of BO handles passed in (size is that times 4). */
> +	__u32 bo_handle_count;
> +
> +	/** A combination of PANFROST_JD_REQ_* */
> +	__u32 requirements;

Do we have a good way of user space determining which requirements are
supported by the driver? At the moment it's just the one. kbase outgeew
the original u16 and has an ugly "compat_core_req", so I suspect you're
going to need to add several more along the way.

You might also want to consider being able to submit more than one job
chain at a time - but that could easily be implemented using a new ioctl
in the future.

> +};
> +
> +/**
> + * struct drm_panfrost_wait_bo - ioctl argument for waiting for
> + * completion of the last DRM_PANFROST_SUBMIT_CL on a BO.

There's no SUBMIT_CL in this posting? I think you just need s/_CL//.

> + *
> + * This is useful for cases where multiple processes might be
> + * rendering to a BO and you want to wait for all rendering to be
> + * completed.
> + */
> +struct drm_panfrost_wait_bo {
> +	__u32 handle;
> +	__u32 pad;
> +	__s64 timeout_ns;	/* absolute */
> +};
> +
> +/**
> + * struct drm_panfrost_create_bo - ioctl argument for creating Panfrost BOs.
> + *
> + * There are currently no values for the flags argument, but it may be
> + * used in a future extension.

You are probably going to want flags for at least:

 * No execute/No read/No write (good for security, especially with
buffer sharing between processes)

 * Alignment (shader programs have quite strict alignment requirements,
I believe kbase just ensures that the shader memory block doesn't cross
a 16MB boundary which covers most cases).

 * Page fault behaviour (kbase has GROW_ON_GPF)

 * Coherency management

> + */
> +struct drm_panfrost_create_bo {
> +	__u32 size;
> +	__u32 flags;
> +	/** Returned GEM handle for the BO. */
> +	__u32 handle;

Padding required here (or reordering)

> +	/**
> +	 * Returned offset for the BO in the GPU address space.  This offset
> +	 * is private to the DRM fd and is valid for the lifetime of the GEM
> +	 * handle.
> +	 *
> +	 * This offset value will always be nonzero, since various HW
> +	 * units treat 0 specially.
> +	 */
> +	__u64 offset;
> +};

I think it's on your todo list, but being able to control the GPU
address is very useful for implementing some of the Khronos APIs (what
kbase calls SAME_VA).

> +
> +/**
> + * struct drm_panfrost_mmap_bo - ioctl argument for mapping Panfrost BOs.
> + *
> + * This doesn't actually perform an mmap.  Instead, it returns the
> + * offset you need to use in an mmap on the DRM device node.  This
> + * means that tools like valgrind end up knowing about the mapped
> + * memory.
> + *
> + * There are currently no values for the flags argument, but it may be
> + * used in a future extension.
> + */
> +struct drm_panfrost_mmap_bo {
> +	/** Handle for the object being mapped. */
> +	__u32 handle;
> +	__u32 flags;
> +	/** offset into the drm node to use for subsequent mmap call. */
> +	__u64 offset;
> +};
> +
> +enum drm_panfrost_param {
> +	DRM_PANFROST_PARAM_GPU_ID,

As mentioned above - this is currently returning the PRODUCT_ID not
GPU_ID...

> +};
> +
> +struct drm_panfrost_get_param {
> +	__u32 param;
> +	__u32 pad;
> +	__u64 value;
> +};
> +
> +/**
> + * Returns the offset for the BO in the GPU address space for this DRM fd.
> + * This is the same value returned by drm_panfrost_create_bo, if that was called
> + * from this DRM fd.
> + */
> +struct drm_panfrost_get_bo_offset {
> +	__u32 handle;
> +	__u32 pad;
> +	__u64 offset;
> +};
> +
> +#if defined(__cplusplus)
> +}
> +#endif
> +
> +#endif /* _PANFROST_DRM_H_ */
> --
> 2.19.1
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
> 

One issue that I haven't got to the bottom of is that I can trigger a
lockdep splat:

-----8<------
panfrost ffa30000.gpu: js fault, js=1, status=JOB_CONFIG_FAULT,
head=0x0, tail=0x0
root@debian:~/ddk_panfrost# panfrost ffa30000.gpu: gpu sched timeout,
js=1, status=0x40, head=0x0, tail=0x0, sched_job=12a94ba6

======================================================
WARNING: possible circular locking dependency detected
5.0.0+ #32 Not tainted
------------------------------------------------------
kworker/1:0/608 is trying to acquire lock:
89b1e2d8 (&(&js->job_lock)->rlock){-.-.}, at:
dma_fence_remove_callback+0x14/0x50

but task is already holding lock:
a887e4b2 (&(&sched->job_list_lock)->rlock){-.-.}, at:
drm_sched_stop+0x24/0x10c

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&(&sched->job_list_lock)->rlock){-.-.}:
       drm_sched_process_job+0x60/0x208
       dma_fence_signal+0x1dc/0x1fc
       panfrost_job_irq_handler+0x160/0x194
       __handle_irq_event_percpu+0x80/0x388
       handle_irq_event_percpu+0x24/0x78
       handle_irq_event+0x38/0x5c
       handle_fasteoi_irq+0xb4/0x128
       generic_handle_irq+0x18/0x28
       __handle_domain_irq+0xa0/0xb4
       gic_handle_irq+0x4c/0x78
       __irq_svc+0x70/0x98
       arch_cpu_idle+0x20/0x3c
       arch_cpu_idle+0x20/0x3c
       do_idle+0x11c/0x22c
       cpu_startup_entry+0x18/0x20
       start_kernel+0x398/0x420

-> #0 (&(&js->job_lock)->rlock){-.-.}:
       _raw_spin_lock_irqsave+0x50/0x64
       dma_fence_remove_callback+0x14/0x50
       drm_sched_stop+0x5c/0x10c
       panfrost_job_timedout+0xd0/0x180
       drm_sched_job_timedout+0x34/0x5c
       process_one_work+0x2ac/0x6a4
       worker_thread+0x28c/0x3fc
       kthread+0x13c/0x158
       ret_from_fork+0x14/0x20
         (null)

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&(&sched->job_list_lock)->rlock);
                               lock(&(&js->job_lock)->rlock);
                               lock(&(&sched->job_list_lock)->rlock);
  lock(&(&js->job_lock)->rlock);

 *** DEADLOCK ***

3 locks held by kworker/1:0/608:
 #0: 9b350627 ((wq_completion)"events"){+.+.}, at:
process_one_work+0x1f8/0x6a4
 #1: a802aa2d ((work_completion)(&(&sched->work_tdr)->work)){+.+.}, at:
process_one_work+0x1f8/0x6a4
 #2: a887e4b2 (&(&sched->job_list_lock)->rlock){-.-.}, at:
drm_sched_stop+0x24/0x10c

stack backtrace:
CPU: 1 PID: 608 Comm: kworker/1:0 Not tainted 5.0.0+ #32
Hardware name: Rockchip (Device Tree)
Workqueue: events drm_sched_job_timedout
[<c0111088>] (unwind_backtrace) from [<c010c9a8>] (show_stack+0x10/0x14)
[<c010c9a8>] (show_stack) from [<c0773df4>] (dump_stack+0x9c/0xd4)
[<c0773df4>] (dump_stack) from [<c016d034>]
(print_circular_bug.constprop.15+0x1fc/0x2cc)
[<c016d034>] (print_circular_bug.constprop.15) from [<c016f6c0>]
(__lock_acquire+0xe5c/0x167c)
[<c016f6c0>] (__lock_acquire) from [<c0170828>] (lock_acquire+0xc4/0x210)
[<c0170828>] (lock_acquire) from [<c07920e0>]
(_raw_spin_lock_irqsave+0x50/0x64)
[<c07920e0>] (_raw_spin_lock_irqsave) from [<c0516784>]
(dma_fence_remove_callback+0x14/0x50)
[<c0516784>] (dma_fence_remove_callback) from [<c04def38>]
(drm_sched_stop+0x5c/0x10c)
[<c04def38>] (drm_sched_stop) from [<c04ec80c>]
(panfrost_job_timedout+0xd0/0x180)
[<c04ec80c>] (panfrost_job_timedout) from [<c04df340>]
(drm_sched_job_timedout+0x34/0x5c)
[<c04df340>] (drm_sched_job_timedout) from [<c013ec70>]
(process_one_work+0x2ac/0x6a4)
[<c013ec70>] (process_one_work) from [<c013fe48>]
(worker_thread+0x28c/0x3fc)
[<c013fe48>] (worker_thread) from [<c01452a0>] (kthread+0x13c/0x158)
[<c01452a0>] (kthread) from [<c01010b4>] (ret_from_fork+0x14/0x20)
Exception stack(0xeebd7fb0 to 0xeebd7ff8)
7fa0:                                     00000000 00000000 00000000
00000000
7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000
7fe0: 00000000 00000000 00000000 00000000 00000013 00000000
----8<----

This is with the below simple reproducer:

----8<----
#include <sys/ioctl.h>
#include <fcntl.h>
#include <stdio.h>

#include <libdrm/drm.h>
#include "panfrost_drm.h"

int main(int argc, char **argv)
{
	int fd;

	if (argc == 2)
		fd = open(argv[1], O_RDWR);
	else
		fd = open("/dev/dri/renderD128", O_RDWR);
	if (fd == -1) {
		perror("Failed to open");
		return 0;
	}

	struct drm_panfrost_submit submit = {
		.jc = 0,
	};
	return ioctl(fd, DRM_IOCTL_PANFROST_SUBMIT, &submit);
}
----8<----

Any ideas? I'm not an expert on DRM, so I got somewhat lost!

Other than that in my testing (on a Firefly RK3288) I didn't experience
any problems pushing jobs from the ARM userspace blob through it.

Steve
On 03/04/2019 05:57, Rob Herring wrote:
[...]
>>> +static int panfrost_clk_init(struct panfrost_device *pfdev)
>>> +{
>>> +     int err;
>>> +     unsigned long rate;
>>> +
>>> +     pfdev->clock = devm_clk_get(pfdev->dev, NULL);
>>> +     if (IS_ERR(pfdev->clock)) {
>>
>> The DT binding says clocks are optional, but this doesn't treat them as
>> such.
> 
> Hum, I would think effectively clocks are always there and necessary
> for thermal reasons.

Should the binding be updated to move clocks from "optional" to 
"required" then? Juno does actually have a GPU clock for DVFS, but the 
clk-scmi driver didn't seem to want to play nicely with either 
mali_kbase or panfrost DRM, so I've just been leaving it out of my DT 
for now (and mali_kbase was perfectly happy without).

>>> +     spin_lock_init(&pfdev->mm_lock);
>>> +
>>> +     /* 4G enough for now. can be 48-bit */
>>> +     drm_mm_init(&pfdev->mm, SZ_32M >> PAGE_SHIFT, SZ_4G);
>>
>> You probably want a dma_set_mask_and_coherent() call for your 'real'
>> output address size somewhere - the default 32-bit mask works out OK for
>> RK3399, but on systems with RAM above 4GB io-pgtable will get very
>> unhappy about DMA bounce-buffering.
> 
> Yes, I have a todo for figuring out the # of physaddr bits in the mmu
> setup (as this call is just relevant to the input address side).
> Though maybe just calling dma_set_mask_and_coherent() is enough and I
> don't need to know the exact number of output bits for the io-pgtable
> setup?

True, io-pgtable itself only really depends on the input size, but in 
order for non-coherent pagtables to work correctly in general, the DMA 
mask does need to be set appropriately, at which point it may as well 
also be propagated into OAS for completeness (as we do in arm-smmu*).

FWIW I'm just gonna leave this quote here...

	gpu_props->mmu.va_bits = KBASE_UBFX32(raw->mmu_features, 0U, 8);
	gpu_props->mmu.pa_bits = KBASE_UBFX32(raw->mmu_features, 8U, 8);


Robin.
> I'm also somewhat surprised that you don't need loads of other
> properties from the GPU - in particular knowing the number of shader
> cores is useful for allocating the right amount of memory for TLS (and
> can't be obtained purely from the GPU_ID).

Since I have no idea what TLS is (and in my notes, I've come across the
acronym once ever and have it as a "??"), I'm not sure how to respond to
that... We don't know how to allocate memory for the GPU-internal data
structures (the tiler heap, for instance, but also a few others I've
just named "misc_0" and "scratchpad" -- guessing one of those is for
"TLS"). With kbase, I took the worst-case strategy of allocating
gigantic chunks on startup with tiny commit counts and GROW_ON_GPF set.
With the new driver, well, our memory consumption is scary since
implementing GROW_ON_GPF in an upstream-friendly way is a bit more work
and isn't expected to hit the 5.2 window.

Given this is kernel facing, I'm hoping 're able to share some answers
here?

> I think this comment might have survived since the very earliest version
> of the Midgard driver! :)

^_^

> But I'm not sure anything will attempt to lock a region spanning two
> pages like that.

At least at the moment, I align everything kernel-facing to page
granularity in userspace, so it's not a cornercase I'm going to hit
anytime soon. Still probably better to have it technically correct.

> To be fair only for BASE_HW_ISSUE_6367/T60X - but yes it's not a
> pleasant workaround. There's no way on that hardware to reliably drain
> the write buffer other than waiting.

*wishing T60X disappeared intensifies* ;)

Granted there are enough other errata specific to it that aren't worked
around here that, well, it makes you wonder ;)

> Do we have a good way of user space determining which requirements are
> supported by the driver? At the moment it's just the one. kbase outgeew
> the original u16 and has an ugly "compat_core_req", so I suspect you're
> going to need to add several more along the way.

Oh, so that's why compat_/core_req is split off! I thought somebody just
thought it would be "fun" to break the UABI ;)

I've definitely issues using the wrong core_req field for the kbase I
had setup, that set me back a little bit on RK3399/T860 bringup *purses
lips*

To be fair, bunches of the kbase reqs are for soft jobs, which I don't
feel are a good fit for how the Panfrost kernel works. If we need to
implement functionality corresponding to softjobs, that would likely be
done with dedicated ioctl(s), instead of affecting the core_req field.

On that note

> You might also want to consider being able to submit more than one job
> chain at a time - but that could easily be implemented using a new ioctl
> in the future.

The issue with that at the bottom is having to introduce something akin
to kbase's annoyingly intra-job-chain dependency management (read: I
still don't understand how FBOs are supposed to work with kbase ;) ),
which AFAIK we push off to userspace right now via standard fencing. If
we want to submit batches at a time, we would potentially need to
express those somewhat complex dependency trees, which is a lot of work
for diminishing returns at this stage. Future ioctl indeed...

> There's no SUBMIT_CL in this posting? I think you just need s/_CL//.

+1

> You are probably going to want flags for at least:
> 
>  * No execute/No read/No write (good for security, especially with
> buffer sharing between processes)
> 
>  * Alignment (shader programs have quite strict alignment requirements,
> I believe kbase just ensures that the shader memory block doesn't cross
> a 16MB boundary which covers most cases).
> 
>  * Page fault behaviour (kbase has GROW_ON_GPF)
> 
>  * Coherency management

+1 for all of these. This is piped through in userspace (for kbase), but
the corresponding functionality isn't there yet in the Panfrost kernel.
You're right there should at least be a flags field for future use.

> One issue that I haven't got to the bottom of is that I can trigger a
> lockdep splat:

Oh, "fun"...

> This is with the below simple reproducer:

@Rob, ideas?

> Other than that in my testing (on a Firefly RK3288) I didn't experience
> any problems pushing jobs from the ARM userspace blob through it.

Nice!

Besides what was mentioned above, any other functionality you'll need
for that? (e.g. the infamous replay workaround...)
On 05/04/2019 17:16, Alyssa Rosenzweig wrote:
>> I'm also somewhat surprised that you don't need loads of other
>> properties from the GPU - in particular knowing the number of shader
>> cores is useful for allocating the right amount of memory for TLS (and
>> can't be obtained purely from the GPU_ID).
> 
> Since I have no idea what TLS is (and in my notes, I've come across the

Sorry - "Thread Local Storage" - e.g. registers spilled to memory from a
shader program.

> acronym once ever and have it as a "??"), I'm not sure how to respond to
> that... We don't know how to allocate memory for the GPU-internal data
> structures (the tiler heap, for instance, but also a few others I've
> just named "misc_0" and "scratchpad" -- guessing one of those is for
> "TLS"). With kbase, I took the worst-case strategy of allocating
> gigantic chunks on startup with tiny commit counts and GROW_ON_GPF set.
> With the new driver, well, our memory consumption is scary since
> implementing GROW_ON_GPF in an upstream-friendly way is a bit more work
> and isn't expected to hit the 5.2 window.

Yes GROW_ON_GPF is pretty much required for the tiler heap - it's not
(reasonably) possible to determine how big it should be. The Arm user
space driver does the same approach (tiny commit count, but allow it to
grow).

> 
> Given this is kernel facing, I'm hoping 're able to share some answers
> here?

At the moment I don't have any permission to share details which aren't
already public in the kbase driver. Hopefully that situation will
change. I'm also very much not an expert on anything but the kernel
driver (I tried to stay away from shader compilers and all that graphics
knowledge...). The details of the job descriptors is only really
publicly documented in terms of the "replay workaround" which is quite
limited.

> 
>> I think this comment might have survived since the very earliest version
>> of the Midgard driver! :)
> 
> ^_^
> 
>> But I'm not sure anything will attempt to lock a region spanning two
>> pages like that.
> 
> At least at the moment, I align everything kernel-facing to page
> granularity in userspace, so it's not a cornercase I'm going to hit
> anytime soon. Still probably better to have it technically correct.
> 
>> To be fair only for BASE_HW_ISSUE_6367/T60X - but yes it's not a
>> pleasant workaround. There's no way on that hardware to reliably drain
>> the write buffer other than waiting.
> 
> *wishing T60X disappeared intensifies* ;)

I think we all felt like that :) Still the Nexus 10 wasn't a bad tablet,
and the Chromebook was an exciting first!

> Granted there are enough other errata specific to it that aren't worked
> around here that, well, it makes you wonder ;)

A lot of the errata are things you only hit with soak testing. So to a
large extent you "get lucky".

>> Do we have a good way of user space determining which requirements are
>> supported by the driver? At the moment it's just the one. kbase outgeew
>> the original u16 and has an ugly "compat_core_req", so I suspect you're
>> going to need to add several more along the way.
> 
> Oh, so that's why compat_/core_req is split off! I thought somebody just
> thought it would be "fun" to break the UABI ;)

No that's a case of us actually not breaking the UABI for once :)

> I've definitely issues using the wrong core_req field for the kbase I
> had setup, that set me back a little bit on RK3399/T860 bringup *purses
> lips*
> 
> To be fair, bunches of the kbase reqs are for soft jobs, which I don't
> feel are a good fit for how the Panfrost kernel works. If we need to
> implement functionality corresponding to softjobs, that would likely be
> done with dedicated ioctl(s), instead of affecting the core_req field.
> 
> On that note
> 
>> You might also want to consider being able to submit more than one job
>> chain at a time - but that could easily be implemented using a new ioctl
>> in the future.
> 
> The issue with that at the bottom is having to introduce something akin
> to kbase's annoyingly intra-job-chain dependency management (read: I
> still don't understand how FBOs are supposed to work with kbase ;) ),
> which AFAIK we push off to userspace right now via standard fencing. If
> we want to submit batches at a time, we would potentially need to
> express those somewhat complex dependency trees, which is a lot of work
> for diminishing returns at this stage. Future ioctl indeed...

You should be able to express the dependencies using fences. At the time
kbase was started there was no fence mechanism in the kernel. We
invented horrible things like UMP[1] and KDS[2] for cross-driver sharing.

It all comes down to how small your job chains are - if you don't need
to squeeze too many through the hardware you should be fine. But there's
going to be some performance gain to be had implementing it.

[1] I forget what it actually stands for, but was an attempt to do
something like dma_buf

[2] "Kernel Dependency System" - a not-so-good version of dma_fence

>> There's no SUBMIT_CL in this posting? I think you just need s/_CL//.
> 
> +1
> 
>> You are probably going to want flags for at least:
>>
>>  * No execute/No read/No write (good for security, especially with
>> buffer sharing between processes)
>>
>>  * Alignment (shader programs have quite strict alignment requirements,
>> I believe kbase just ensures that the shader memory block doesn't cross
>> a 16MB boundary which covers most cases).
>>
>>  * Page fault behaviour (kbase has GROW_ON_GPF)
>>
>>  * Coherency management
> 
> +1 for all of these. This is piped through in userspace (for kbase), but
> the corresponding functionality isn't there yet in the Panfrost kernel.
> You're right there should at least be a flags field for future use.
> 
>> One issue that I haven't got to the bottom of is that I can trigger a
>> lockdep splat:
> 
> Oh, "fun"...
> 
>> This is with the below simple reproducer:
> 
> @Rob, ideas?
> 
>> Other than that in my testing (on a Firefly RK3288) I didn't experience
>> any problems pushing jobs from the ARM userspace blob through it.
> 
> Nice!
> 
> Besides what was mentioned above, any other functionality you'll need
> for that? (e.g. the infamous replay workaround...)

If you don't implement the replay workaround I'm very happy :)

The main missing part for the Arm user space is feature registers. That
and the lack of SAME_VA is horrible to emulate (keep allocating until it
happens to land in a free area of user space memory).

Arm user space also makes use of cached memory with explicit cache sync
operations. It of course works fine with uncached and ignoring the sync,
but again I'm not sure how much performance is being lost.

Steve
> Sorry - "Thread Local Storage" - e.g. registers spilled to memory from a
> shader program.

Gotcha, thank you. Register spilling isn't implemented yet, so I haven't
run into this. (Partially because the blob's RA is very good so it's
somewhat nontrivial to get it to spill... not that I've tried, the real
reason is that the RA I have implemented right now works and I don't
want to mess with it ;P)

> At the moment I don't have any permission to share details which aren't
> already public in the kbase driver. Hopefully that situation will
> change. I'm also very much not an expert on anything but the kernel
> driver (I tried to stay away from shader compilers and all that graphics
> knowledge...). The details of the job descriptors is only really
> publicly documented in terms of the "replay workaround" which is quite
> limited.

Alright, no worries! We'll see where the tide turns, indeed :)

> I think we all felt like that :) Still the Nexus 10 wasn't a bad tablet,
> and the Chromebook was an exciting first!

*looks around to 2 Kevins and 2 Veyrons sprawled about* At first,
indeeed.... ;)

> You should be able to express the dependencies using fences. At the time
> kbase was started there was no fence mechanism in the kernel. We
> invented horrible things like UMP[1] and KDS[2] for cross-driver sharing.

Ah-ha, I see; I didn't know if there was an explicit reason kbase didn't
use fencing, but if it didn't exist, that's reason enough.

> It all comes down to how small your job chains are - if you don't need
> to squeeze too many through the hardware you should be fine. But there's
> going to be some performance gain to be had implementing it.

For sure.

> [1] I forget what it actually stands for, but was an attempt to do
> something like dma_buf

Unified Memory Provider, iirc.

> If you don't implement the replay workaround I'm very happy :)

Pff.

> The main missing part for the Arm user space is feature registers. That
> and the lack of SAME_VA is horrible to emulate (keep allocating until it
> happens to land in a free area of user space memory).

Alright, both of those will probably be needed for us sooner or later,
so no harm in implementing those. Thank you!

> Arm user space also makes use of cached memory with explicit cache sync
> operations. It of course works fine with uncached and ignoring the sync,
> but again I'm not sure how much performance is being lost.

I would be interested as well, since even when I used kbase for stuff, I set
everything uncached/unsynced to keep myself sane, but that could be a
very real performance issue on some workloads.
On Fri, Apr 5, 2019 at 7:30 AM Steven Price <steven.price@arm.com> wrote:
>
> On 01/04/2019 08:47, Rob Herring wrote:
> > This adds the initial driver for panfrost which supports Arm Mali
> > Midgard and Bifrost family of GPUs. Currently, only the T860 and
> > T760 Midgard GPUs have been tested.

[...]

> > +     case 0xD3: return "TRANSTAB_BUS_FAULT_LEVEL3";
> > +     case 0xD4: return "TRANSTAB_BUS_FAULT_LEVEL4";
> > +     case 0xD8: return "ACCESS_FLAG";
> > +     }
> > +
> > +     if (panfrost_has_hw_feature(pfdev, HW_FEATURE_AARCH64_MMU)) {
>
> There's not a great deal of point in this conditional - you won't get
> the below exception codes from hardware which doesn't support it AARCH64
> page tables.

I wasn't sure if "UNKNOWN" types could happen or not.

>
> > +             switch (exception_code) {
> > +             case 0xC9 ... 0xCF: return "PERMISSION_FAULT";
> > +             case 0xD9 ... 0xDF: return "ACCESS_FLAG";
> > +             case 0xE0 ... 0xE7: return "ADDRESS_SIZE_FAULT";
> > +             case 0xE8 ... 0xEF: return "MEMORY_ATTRIBUTES_FAULT";
> > +             }
> > +     }
> > +
> > +     return "UNKNOWN";
> > +}

> > +static inline int panfrost_model_cmp(struct panfrost_device *pfdev, s32 id)
> > +{
> > +     s32 match_id = pfdev->features.id;
> > +
> > +     if (match_id & 0xf000)
> > +             match_id &= 0xf00f;
>
> I'm puzzled by this, and really not sure if it's going to work out
> ignoring the ARCH_MINOR/ARCH_REV fields. But for now there's no real
> Bifrost support.

That seemed to be enough for kbase to select features/issues.

> > +     switch (param->param) {
> > +     case DRM_PANFROST_PARAM_GPU_ID:
> > +             param->value = pfdev->features.id;
>
> This is unfortunate naming - this parameter is *not* the GPU_ID. It is
> the top half of the GPU_ID which kbase calls the PRODUCT_ID.

I can rename it.

> I'm also somewhat surprised that you don't need loads of other
> properties from the GPU - in particular knowing the number of shader
> cores is useful for allocating the right amount of memory for TLS (and
> can't be obtained purely from the GPU_ID).

We'll add them as userspace needs them.

> > +static int
> > +panfrost_lookup_bos(struct drm_device *dev,
> > +               struct drm_file *file_priv,
> > +               struct drm_panfrost_submit *args,
> > +               struct panfrost_job *job)
> > +{
> > +     u32 *handles;
> > +     int ret = 0;
> > +
> > +     job->bo_count = args->bo_handle_count;
> > +
> > +     if (!job->bo_count)
> > +             return 0;
> > +
> > +     job->bos = kvmalloc_array(job->bo_count,
> > +                               sizeof(struct drm_gem_object *),
> > +                               GFP_KERNEL | __GFP_ZERO);
> > +     if (!job->bos)
>
> If we return here then job->bo_count has been set, but job->bos is
> invalid - this means that panfrost_job_cleanup() will then dereference
> NULL. Although maybe this is better fixed in panfrost_job_cleanup().

Good catch. The fence arrays have the same problem. As does V3D which we copied.

> > +             return -ENOMEM;
> > +
> > +     job->implicit_fences = kvmalloc_array(job->bo_count,
> > +                               sizeof(struct dma_fence *),
> > +                               GFP_KERNEL | __GFP_ZERO);
> > +     if (!job->implicit_fences)
> > +             return -ENOMEM;

> > +static irqreturn_t panfrost_gpu_irq_handler(int irq, void *data)
> > +{
> > +     struct panfrost_device *pfdev = data;
> > +     u32 state = gpu_read(pfdev, GPU_INT_STAT);
> > +     u32 fault_status = gpu_read(pfdev, GPU_FAULT_STATUS);
> > +     u64 address;
> > +     bool done = false;
> > +
> > +     if (!state)
> > +             return IRQ_NONE;
> > +
> > +     if (state & GPU_IRQ_MASK_ERROR) {
> > +             address = (u64) gpu_read(pfdev, GPU_FAULT_ADDRESS_HI) << 32;
> > +             address |= gpu_read(pfdev, GPU_FAULT_ADDRESS_LO);
> > +
> > +             dev_warn(pfdev->dev, "GPU Fault 0x%08x (%s) at 0x%016llx\n",
> > +                      fault_status & 0xFF, panfrost_exception_name(pfdev, fault_status),
> > +                      address);
> > +
> > +             if (state & GPU_IRQ_MULTIPLE_FAULT)
> > +                     dev_warn(pfdev->dev, "There were multiple GPU faults - some have not been reported\n");
> > +
> > +             gpu_write(pfdev, GPU_INT_MASK, 0);
>
> Do you intend to mask off future GPU interrupts?

Yes, maybe?

If we fault here, then we are going to reset the gpu on timeout which
then re-enables interrupts.


> > +static irqreturn_t panfrost_job_irq_handler(int irq, void *data)
> > +{
> > +     struct panfrost_device *pfdev = data;
> > +     u32 status = job_read(pfdev, JOB_INT_STAT);
> > +     int j;
> > +
> > +     dev_dbg(pfdev->dev, "jobslot irq status=%x\n", status);
> > +
> > +     if (!status)
> > +             return IRQ_NONE;
> > +
> > +     pm_runtime_mark_last_busy(pfdev->dev);
> > +
> > +     for (j = 0; status; j++) {
> > +             u32 mask = MK_JS_MASK(j);
> > +
> > +             if (!(status & mask))
> > +                     continue;
> > +
> > +             job_write(pfdev, JOB_INT_CLEAR, mask);
> > +
> > +             if (status & JOB_INT_MASK_ERR(j)) {
> > +                     job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_NOP);
> > +                     job_write(pfdev, JS_COMMAND(j), JS_COMMAND_HARD_STOP_0);
>
> Hard-stopping an already completed job isn't likely to do very much :)
> Also you are using the "_0" version which is only valid when "job chain
> disambiguation" is present.
>
> I suspect in this case you should also be signalling the fence? At the
> moment you rely on the GPU timeout recovering from the fault.

I'll defer to Tomeu who wrote this (IIRC).


> > +static void lock_region(struct panfrost_device *pfdev, u32 as_nr,
> > +                     u64 iova, size_t size)
> > +{
> > +     u8 region_width;
> > +     u64 region = iova & PAGE_MASK;
> > +     /*
> > +      * fls returns (given the ASSERT above):
>
> But where's the assert? :p
>
> > +      * 1 .. 32
> > +      *
> > +      * 10 + fls(num_pages)
> > +      * results in the range (11 .. 42)
> > +      */
> > +
> > +     size = round_up(size, PAGE_SIZE);
>
> I'm not sure it matters, but this will break if called on a (small, i.e.
> less than a page) region spanning two pages. "region" will be rounded
> down to the page (iova & PAGE_MASK), but size will only be rounded up to
> the nearest page. This can miss the start of the second page.

This is probably redundant. Everything the driver does with memory is
in units of pages. Maybe imported buffers could be unaligned. Not sure
and we'd probably break in other places if that was the case.


> > +             /* terminal fault, print info about the fault */
> > +             dev_err(pfdev->dev,
> > +                     "Unhandled Page fault in AS%d at VA 0x%016llX\n"
> > +                     "Reason: %s\n"
> > +                     "raw fault status: 0x%X\n"
> > +                     "decoded fault status: %s\n"
> > +                     "exception type 0x%X: %s\n"
> > +                     "access type 0x%X: %s\n"
> > +                     "source id 0x%X\n",
> > +                     i, addr,
> > +                     "TODO",
> > +                     fault_status,
> > +                     (fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
> > +                     exception_type, panfrost_exception_name(pfdev, exception_type),
> > +                     access_type, access_type_name(pfdev, fault_status),
> > +                     source_id);
> > +
> > +             mmu_write(pfdev, MMU_INT_CLEAR, mask);
>
> To fully handle the fault you will need to issue an MMU command (i.e.
> call mmu_hw_do_operation()) - obviously after doing something to fix the
> cause (e.g. mapping a page or switching the GPU to UNMAPPED mode to kill
> off the job). Otherwise you may see that the GPU hangs. Although in
> practice at this stage of the driver the generic timeout is probably the
> simplest way of handling an MMU fault.

Any fault currently is unexpected so all we really care about at this
point is getting a message.


> > +/**
> > + * struct drm_panfrost_create_bo - ioctl argument for creating Panfrost BOs.
> > + *
> > + * There are currently no values for the flags argument, but it may be
> > + * used in a future extension.
>
> You are probably going to want flags for at least:
>
>  * No execute/No read/No write (good for security, especially with
> buffer sharing between processes)
>
>  * Alignment (shader programs have quite strict alignment requirements,
> I believe kbase just ensures that the shader memory block doesn't cross
> a 16MB boundary which covers most cases).
>
>  * Page fault behaviour (kbase has GROW_ON_GPF)
>
>  * Coherency management

Yep, will add them as needed.

> One issue that I haven't got to the bottom of is that I can trigger a
> lockdep splat:
>
> -----8<------
> panfrost ffa30000.gpu: js fault, js=1, status=JOB_CONFIG_FAULT,
> head=0x0, tail=0x0
> root@debian:~/ddk_panfrost# panfrost ffa30000.gpu: gpu sched timeout,
> js=1, status=0x40, head=0x0, tail=0x0, sched_job=12a94ba6
>
> ======================================================
> WARNING: possible circular locking dependency detected
> 5.0.0+ #32 Not tainted
> ------------------------------------------------------
> kworker/1:0/608 is trying to acquire lock:
> 89b1e2d8 (&(&js->job_lock)->rlock){-.-.}, at:
> dma_fence_remove_callback+0x14/0x50
>
> but task is already holding lock:
> a887e4b2 (&(&sched->job_list_lock)->rlock){-.-.}, at:
> drm_sched_stop+0x24/0x10c
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #1 (&(&sched->job_list_lock)->rlock){-.-.}:
>        drm_sched_process_job+0x60/0x208
>        dma_fence_signal+0x1dc/0x1fc
>        panfrost_job_irq_handler+0x160/0x194
>        __handle_irq_event_percpu+0x80/0x388
>        handle_irq_event_percpu+0x24/0x78
>        handle_irq_event+0x38/0x5c
>        handle_fasteoi_irq+0xb4/0x128
>        generic_handle_irq+0x18/0x28
>        __handle_domain_irq+0xa0/0xb4
>        gic_handle_irq+0x4c/0x78
>        __irq_svc+0x70/0x98
>        arch_cpu_idle+0x20/0x3c
>        arch_cpu_idle+0x20/0x3c
>        do_idle+0x11c/0x22c
>        cpu_startup_entry+0x18/0x20
>        start_kernel+0x398/0x420
>
> -> #0 (&(&js->job_lock)->rlock){-.-.}:
>        _raw_spin_lock_irqsave+0x50/0x64
>        dma_fence_remove_callback+0x14/0x50
>        drm_sched_stop+0x5c/0x10c
>        panfrost_job_timedout+0xd0/0x180
>        drm_sched_job_timedout+0x34/0x5c
>        process_one_work+0x2ac/0x6a4
>        worker_thread+0x28c/0x3fc
>        kthread+0x13c/0x158
>        ret_from_fork+0x14/0x20
>          (null)
>
> other info that might help us debug this:
>
>  Possible unsafe locking scenario:
>
>        CPU0                    CPU1
>        ----                    ----
>   lock(&(&sched->job_list_lock)->rlock);
>                                lock(&(&js->job_lock)->rlock);
>                                lock(&(&sched->job_list_lock)->rlock);
>   lock(&(&js->job_lock)->rlock);
>
>  *** DEADLOCK ***
>
> 3 locks held by kworker/1:0/608:
>  #0: 9b350627 ((wq_completion)"events"){+.+.}, at:
> process_one_work+0x1f8/0x6a4
>  #1: a802aa2d ((work_completion)(&(&sched->work_tdr)->work)){+.+.}, at:
> process_one_work+0x1f8/0x6a4
>  #2: a887e4b2 (&(&sched->job_list_lock)->rlock){-.-.}, at:
> drm_sched_stop+0x24/0x10c
>
> stack backtrace:
> CPU: 1 PID: 608 Comm: kworker/1:0 Not tainted 5.0.0+ #32
> Hardware name: Rockchip (Device Tree)
> Workqueue: events drm_sched_job_timedout
> [<c0111088>] (unwind_backtrace) from [<c010c9a8>] (show_stack+0x10/0x14)
> [<c010c9a8>] (show_stack) from [<c0773df4>] (dump_stack+0x9c/0xd4)
> [<c0773df4>] (dump_stack) from [<c016d034>]
> (print_circular_bug.constprop.15+0x1fc/0x2cc)
> [<c016d034>] (print_circular_bug.constprop.15) from [<c016f6c0>]
> (__lock_acquire+0xe5c/0x167c)
> [<c016f6c0>] (__lock_acquire) from [<c0170828>] (lock_acquire+0xc4/0x210)
> [<c0170828>] (lock_acquire) from [<c07920e0>]
> (_raw_spin_lock_irqsave+0x50/0x64)
> [<c07920e0>] (_raw_spin_lock_irqsave) from [<c0516784>]
> (dma_fence_remove_callback+0x14/0x50)
> [<c0516784>] (dma_fence_remove_callback) from [<c04def38>]
> (drm_sched_stop+0x5c/0x10c)
> [<c04def38>] (drm_sched_stop) from [<c04ec80c>]
> (panfrost_job_timedout+0xd0/0x180)
> [<c04ec80c>] (panfrost_job_timedout) from [<c04df340>]
> (drm_sched_job_timedout+0x34/0x5c)
> [<c04df340>] (drm_sched_job_timedout) from [<c013ec70>]
> (process_one_work+0x2ac/0x6a4)
> [<c013ec70>] (process_one_work) from [<c013fe48>]
> (worker_thread+0x28c/0x3fc)
> [<c013fe48>] (worker_thread) from [<c01452a0>] (kthread+0x13c/0x158)
> [<c01452a0>] (kthread) from [<c01010b4>] (ret_from_fork+0x14/0x20)
> Exception stack(0xeebd7fb0 to 0xeebd7ff8)
> 7fa0:                                     00000000 00000000 00000000
> 00000000
> 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> 00000000
> 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> ----8<----
>
> This is with the below simple reproducer:
>
> ----8<----
> #include <sys/ioctl.h>
> #include <fcntl.h>
> #include <stdio.h>
>
> #include <libdrm/drm.h>
> #include "panfrost_drm.h"
>
> int main(int argc, char **argv)
> {
>         int fd;
>
>         if (argc == 2)
>                 fd = open(argv[1], O_RDWR);
>         else
>                 fd = open("/dev/dri/renderD128", O_RDWR);
>         if (fd == -1) {
>                 perror("Failed to open");
>                 return 0;
>         }
>
>         struct drm_panfrost_submit submit = {
>                 .jc = 0,
>         };
>         return ioctl(fd, DRM_IOCTL_PANFROST_SUBMIT, &submit);
> }
> ----8<----
>
> Any ideas? I'm not an expert on DRM, so I got somewhat lost!

Tomeu?

Rob
On Mon, 8 Apr 2019 at 23:04, Rob Herring <robh@kernel.org> wrote:
>
> On Fri, Apr 5, 2019 at 7:30 AM Steven Price <steven.price@arm.com> wrote:
> >
> > On 01/04/2019 08:47, Rob Herring wrote:
> > > This adds the initial driver for panfrost which supports Arm Mali
> > > Midgard and Bifrost family of GPUs. Currently, only the T860 and
> > > T760 Midgard GPUs have been tested.
>
> [...]
> > > +
> > > +             if (status & JOB_INT_MASK_ERR(j)) {
> > > +                     job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_NOP);
> > > +                     job_write(pfdev, JS_COMMAND(j), JS_COMMAND_HARD_STOP_0);
> >
> > Hard-stopping an already completed job isn't likely to do very much :)
> > Also you are using the "_0" version which is only valid when "job chain
> > disambiguation" is present.

Yeah, guess that can be removed.

> > I suspect in this case you should also be signalling the fence? At the
> > moment you rely on the GPU timeout recovering from the fault.
>
> I'll defer to Tomeu who wrote this (IIRC).

Yes, that would be an improvement.

> > One issue that I haven't got to the bottom of is that I can trigger a
> > lockdep splat:
> >
> > -----8<------
> > panfrost ffa30000.gpu: js fault, js=1, status=JOB_CONFIG_FAULT,
> > head=0x0, tail=0x0
> > root@debian:~/ddk_panfrost# panfrost ffa30000.gpu: gpu sched timeout,
> > js=1, status=0x40, head=0x0, tail=0x0, sched_job=12a94ba6
> >
> > ======================================================
> > WARNING: possible circular locking dependency detected
> > 5.0.0+ #32 Not tainted
> > ------------------------------------------------------
> > kworker/1:0/608 is trying to acquire lock:
> > 89b1e2d8 (&(&js->job_lock)->rlock){-.-.}, at:
> > dma_fence_remove_callback+0x14/0x50
> >
> > but task is already holding lock:
> > a887e4b2 (&(&sched->job_list_lock)->rlock){-.-.}, at:
> > drm_sched_stop+0x24/0x10c
> >
> > which lock already depends on the new lock.
> >
> >
> > the existing dependency chain (in reverse order) is:
> >
> > -> #1 (&(&sched->job_list_lock)->rlock){-.-.}:
> >        drm_sched_process_job+0x60/0x208
> >        dma_fence_signal+0x1dc/0x1fc
> >        panfrost_job_irq_handler+0x160/0x194
> >        __handle_irq_event_percpu+0x80/0x388
> >        handle_irq_event_percpu+0x24/0x78
> >        handle_irq_event+0x38/0x5c
> >        handle_fasteoi_irq+0xb4/0x128
> >        generic_handle_irq+0x18/0x28
> >        __handle_domain_irq+0xa0/0xb4
> >        gic_handle_irq+0x4c/0x78
> >        __irq_svc+0x70/0x98
> >        arch_cpu_idle+0x20/0x3c
> >        arch_cpu_idle+0x20/0x3c
> >        do_idle+0x11c/0x22c
> >        cpu_startup_entry+0x18/0x20
> >        start_kernel+0x398/0x420
> >
> > -> #0 (&(&js->job_lock)->rlock){-.-.}:
> >        _raw_spin_lock_irqsave+0x50/0x64
> >        dma_fence_remove_callback+0x14/0x50
> >        drm_sched_stop+0x5c/0x10c
> >        panfrost_job_timedout+0xd0/0x180
> >        drm_sched_job_timedout+0x34/0x5c
> >        process_one_work+0x2ac/0x6a4
> >        worker_thread+0x28c/0x3fc
> >        kthread+0x13c/0x158
> >        ret_from_fork+0x14/0x20
> >          (null)
> >
> > other info that might help us debug this:
> >
> >  Possible unsafe locking scenario:
> >
> >        CPU0                    CPU1
> >        ----                    ----
> >   lock(&(&sched->job_list_lock)->rlock);
> >                                lock(&(&js->job_lock)->rlock);
> >                                lock(&(&sched->job_list_lock)->rlock);
> >   lock(&(&js->job_lock)->rlock);
> >
> >  *** DEADLOCK ***
> >
> > 3 locks held by kworker/1:0/608:
> >  #0: 9b350627 ((wq_completion)"events"){+.+.}, at:
> > process_one_work+0x1f8/0x6a4
> >  #1: a802aa2d ((work_completion)(&(&sched->work_tdr)->work)){+.+.}, at:
> > process_one_work+0x1f8/0x6a4
> >  #2: a887e4b2 (&(&sched->job_list_lock)->rlock){-.-.}, at:
> > drm_sched_stop+0x24/0x10c
> >
> > stack backtrace:
> > CPU: 1 PID: 608 Comm: kworker/1:0 Not tainted 5.0.0+ #32
> > Hardware name: Rockchip (Device Tree)
> > Workqueue: events drm_sched_job_timedout
> > [<c0111088>] (unwind_backtrace) from [<c010c9a8>] (show_stack+0x10/0x14)
> > [<c010c9a8>] (show_stack) from [<c0773df4>] (dump_stack+0x9c/0xd4)
> > [<c0773df4>] (dump_stack) from [<c016d034>]
> > (print_circular_bug.constprop.15+0x1fc/0x2cc)
> > [<c016d034>] (print_circular_bug.constprop.15) from [<c016f6c0>]
> > (__lock_acquire+0xe5c/0x167c)
> > [<c016f6c0>] (__lock_acquire) from [<c0170828>] (lock_acquire+0xc4/0x210)
> > [<c0170828>] (lock_acquire) from [<c07920e0>]
> > (_raw_spin_lock_irqsave+0x50/0x64)
> > [<c07920e0>] (_raw_spin_lock_irqsave) from [<c0516784>]
> > (dma_fence_remove_callback+0x14/0x50)
> > [<c0516784>] (dma_fence_remove_callback) from [<c04def38>]
> > (drm_sched_stop+0x5c/0x10c)
> > [<c04def38>] (drm_sched_stop) from [<c04ec80c>]
> > (panfrost_job_timedout+0xd0/0x180)
> > [<c04ec80c>] (panfrost_job_timedout) from [<c04df340>]
> > (drm_sched_job_timedout+0x34/0x5c)
> > [<c04df340>] (drm_sched_job_timedout) from [<c013ec70>]
> > (process_one_work+0x2ac/0x6a4)
> > [<c013ec70>] (process_one_work) from [<c013fe48>]
> > (worker_thread+0x28c/0x3fc)
> > [<c013fe48>] (worker_thread) from [<c01452a0>] (kthread+0x13c/0x158)
> > [<c01452a0>] (kthread) from [<c01010b4>] (ret_from_fork+0x14/0x20)
> > Exception stack(0xeebd7fb0 to 0xeebd7ff8)
> > 7fa0:                                     00000000 00000000 00000000
> > 00000000
> > 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> > 00000000
> > 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > ----8<----
> >
> > This is with the below simple reproducer:
> >
> > ----8<----
> > #include <sys/ioctl.h>
> > #include <fcntl.h>
> > #include <stdio.h>
> >
> > #include <libdrm/drm.h>
> > #include "panfrost_drm.h"
> >
> > int main(int argc, char **argv)
> > {
> >         int fd;
> >
> >         if (argc == 2)
> >                 fd = open(argv[1], O_RDWR);
> >         else
> >                 fd = open("/dev/dri/renderD128", O_RDWR);
> >         if (fd == -1) {
> >                 perror("Failed to open");
> >                 return 0;
> >         }
> >
> >         struct drm_panfrost_submit submit = {
> >                 .jc = 0,
> >         };
> >         return ioctl(fd, DRM_IOCTL_PANFROST_SUBMIT, &submit);
> > }
> > ----8<----
> >
> > Any ideas? I'm not an expert on DRM, so I got somewhat lost!
>
> Tomeu?

Ran out of time today, but will be able to look at it tomorrow.

Thanks!

Tomeu
On Tue, Apr 9, 2019 at 10:56 AM Tomeu Vizoso <tomeu.vizoso@collabora.com> wrote:
>
> On Mon, 8 Apr 2019 at 23:04, Rob Herring <robh@kernel.org> wrote:
> >
> > On Fri, Apr 5, 2019 at 7:30 AM Steven Price <steven.price@arm.com> wrote:
> > >
> > > On 01/04/2019 08:47, Rob Herring wrote:
> > > > This adds the initial driver for panfrost which supports Arm Mali
> > > > Midgard and Bifrost family of GPUs. Currently, only the T860 and
> > > > T760 Midgard GPUs have been tested.
> >
> > [...]
> > > > +
> > > > +             if (status & JOB_INT_MASK_ERR(j)) {
> > > > +                     job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_NOP);
> > > > +                     job_write(pfdev, JS_COMMAND(j), JS_COMMAND_HARD_STOP_0);
> > >
> > > Hard-stopping an already completed job isn't likely to do very much :)
> > > Also you are using the "_0" version which is only valid when "job chain
> > > disambiguation" is present.
>
> Yeah, guess that can be removed.

Steven, TBC, are you suggesting removing both lines or leaving
JS_COMMAND_NOP? I don't think we can ever have a pending job at this
point as there's no queuing. So the NOP probably isn't needed, but
doesn't hurt to have it either.

> > > I suspect in this case you should also be signalling the fence? At the
> > > moment you rely on the GPU timeout recovering from the fault.
> >
> > I'll defer to Tomeu who wrote this (IIRC).
>
> Yes, that would be an improvement.

Actually, I think that would break recovery because the job timeout
will bail out if the done fence is signaled already. Perhaps we want
to timeout immediately if that is possible with the scheduler.

Rob
On 08/04/2019 22:04, Rob Herring wrote:
> On Fri, Apr 5, 2019 at 7:30 AM Steven Price <steven.price@arm.com> wrote:
>>
>> On 01/04/2019 08:47, Rob Herring wrote:
>>> This adds the initial driver for panfrost which supports Arm Mali
>>> Midgard and Bifrost family of GPUs. Currently, only the T860 and
>>> T760 Midgard GPUs have been tested.
> 
> [...]
> 
>>> +     case 0xD3: return "TRANSTAB_BUS_FAULT_LEVEL3";
>>> +     case 0xD4: return "TRANSTAB_BUS_FAULT_LEVEL4";
>>> +     case 0xD8: return "ACCESS_FLAG";
>>> +     }
>>> +
>>> +     if (panfrost_has_hw_feature(pfdev, HW_FEATURE_AARCH64_MMU)) {
>>
>> There's not a great deal of point in this conditional - you won't get
>> the below exception codes from hardware which doesn't support it AARCH64
>> page tables.
> 
> I wasn't sure if "UNKNOWN" types could happen or not.
> 
>>
>>> +             switch (exception_code) {
>>> +             case 0xC9 ... 0xCF: return "PERMISSION_FAULT";
>>> +             case 0xD9 ... 0xDF: return "ACCESS_FLAG";
>>> +             case 0xE0 ... 0xE7: return "ADDRESS_SIZE_FAULT";
>>> +             case 0xE8 ... 0xEF: return "MEMORY_ATTRIBUTES_FAULT";
>>> +             }
>>> +     }
>>> +
>>> +     return "UNKNOWN";
>>> +}
> 
>>> +static inline int panfrost_model_cmp(struct panfrost_device *pfdev, s32 id)
>>> +{
>>> +     s32 match_id = pfdev->features.id;
>>> +
>>> +     if (match_id & 0xf000)
>>> +             match_id &= 0xf00f;
>>
>> I'm puzzled by this, and really not sure if it's going to work out
>> ignoring the ARCH_MINOR/ARCH_REV fields. But for now there's no real
>> Bifrost support.
> 
> That seemed to be enough for kbase to select features/issues.

I can't deny that it seems to work for now, and indeed looking more
closely at kbase that does seem to be the effect of the current code.

>>> +     switch (param->param) {
>>> +     case DRM_PANFROST_PARAM_GPU_ID:
>>> +             param->value = pfdev->features.id;
>>
>> This is unfortunate naming - this parameter is *not* the GPU_ID. It is
>> the top half of the GPU_ID which kbase calls the PRODUCT_ID.
> 
> I can rename it.

It would help prevent confusion, thanks!

>> I'm also somewhat surprised that you don't need loads of other
>> properties from the GPU - in particular knowing the number of shader
>> cores is useful for allocating the right amount of memory for TLS (and
>> can't be obtained purely from the GPU_ID).
> 
> We'll add them as userspace needs them.

Fair enough. I'm not sure how much you want to provide "forward
compatibility" by providing them early - the basic definitions are
already in kbase. I found it a bit surprising that some feature
registers are printed on probe, but not available to be queried.

>>> +static int
>>> +panfrost_lookup_bos(struct drm_device *dev,
>>> +               struct drm_file *file_priv,
>>> +               struct drm_panfrost_submit *args,
>>> +               struct panfrost_job *job)
>>> +{
>>> +     u32 *handles;
>>> +     int ret = 0;
>>> +
>>> +     job->bo_count = args->bo_handle_count;
>>> +
>>> +     if (!job->bo_count)
>>> +             return 0;
>>> +
>>> +     job->bos = kvmalloc_array(job->bo_count,
>>> +                               sizeof(struct drm_gem_object *),
>>> +                               GFP_KERNEL | __GFP_ZERO);
>>> +     if (!job->bos)
>>
>> If we return here then job->bo_count has been set, but job->bos is
>> invalid - this means that panfrost_job_cleanup() will then dereference
>> NULL. Although maybe this is better fixed in panfrost_job_cleanup().
> 
> Good catch. The fence arrays have the same problem. As does V3D which we copied.
> 
>>> +             return -ENOMEM;
>>> +
>>> +     job->implicit_fences = kvmalloc_array(job->bo_count,
>>> +                               sizeof(struct dma_fence *),
>>> +                               GFP_KERNEL | __GFP_ZERO);
>>> +     if (!job->implicit_fences)
>>> +             return -ENOMEM;
> 
>>> +static irqreturn_t panfrost_gpu_irq_handler(int irq, void *data)
>>> +{
>>> +     struct panfrost_device *pfdev = data;
>>> +     u32 state = gpu_read(pfdev, GPU_INT_STAT);
>>> +     u32 fault_status = gpu_read(pfdev, GPU_FAULT_STATUS);
>>> +     u64 address;
>>> +     bool done = false;
>>> +
>>> +     if (!state)
>>> +             return IRQ_NONE;
>>> +
>>> +     if (state & GPU_IRQ_MASK_ERROR) {
>>> +             address = (u64) gpu_read(pfdev, GPU_FAULT_ADDRESS_HI) << 32;
>>> +             address |= gpu_read(pfdev, GPU_FAULT_ADDRESS_LO);
>>> +
>>> +             dev_warn(pfdev->dev, "GPU Fault 0x%08x (%s) at 0x%016llx\n",
>>> +                      fault_status & 0xFF, panfrost_exception_name(pfdev, fault_status),
>>> +                      address);
>>> +
>>> +             if (state & GPU_IRQ_MULTIPLE_FAULT)
>>> +                     dev_warn(pfdev->dev, "There were multiple GPU faults - some have not been reported\n");
>>> +
>>> +             gpu_write(pfdev, GPU_INT_MASK, 0);
>>
>> Do you intend to mask off future GPU interrupts?
> 
> Yes, maybe?
> 
> If we fault here, then we are going to reset the gpu on timeout which
> then re-enables interrupts.

Well fair enough. But there's no actual need to force a GPU reset.
Really there's nothing you can do other than report a GPU fault. kbase
simply reports it and otherwise ignores it (no GPU reset).

Also will you actually trigger the GPU timeout? This won't mask of the
JOB completion IRQ, so jobs can still complete.

When you integrate other GPU irq sources (counters/power management)
then you almost certainly don't want to mask those off just because of a
GPU fault.

>>> +static irqreturn_t panfrost_job_irq_handler(int irq, void *data)
>>> +{
>>> +     struct panfrost_device *pfdev = data;
>>> +     u32 status = job_read(pfdev, JOB_INT_STAT);
>>> +     int j;
>>> +
>>> +     dev_dbg(pfdev->dev, "jobslot irq status=%x\n", status);
>>> +
>>> +     if (!status)
>>> +             return IRQ_NONE;
>>> +
>>> +     pm_runtime_mark_last_busy(pfdev->dev);
>>> +
>>> +     for (j = 0; status; j++) {
>>> +             u32 mask = MK_JS_MASK(j);
>>> +
>>> +             if (!(status & mask))
>>> +                     continue;
>>> +
>>> +             job_write(pfdev, JOB_INT_CLEAR, mask);
>>> +
>>> +             if (status & JOB_INT_MASK_ERR(j)) {
>>> +                     job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_NOP);
>>> +                     job_write(pfdev, JS_COMMAND(j), JS_COMMAND_HARD_STOP_0);
>>
>> Hard-stopping an already completed job isn't likely to do very much :)
>> Also you are using the "_0" version which is only valid when "job chain
>> disambiguation" is present.
>>
>> I suspect in this case you should also be signalling the fence? At the
>> moment you rely on the GPU timeout recovering from the fault.
> 
> I'll defer to Tomeu who wrote this (IIRC).
> 
> 
>>> +static void lock_region(struct panfrost_device *pfdev, u32 as_nr,
>>> +                     u64 iova, size_t size)
>>> +{
>>> +     u8 region_width;
>>> +     u64 region = iova & PAGE_MASK;
>>> +     /*
>>> +      * fls returns (given the ASSERT above):
>>
>> But where's the assert? :p
>>
>>> +      * 1 .. 32
>>> +      *
>>> +      * 10 + fls(num_pages)
>>> +      * results in the range (11 .. 42)
>>> +      */
>>> +
>>> +     size = round_up(size, PAGE_SIZE);
>>
>> I'm not sure it matters, but this will break if called on a (small, i.e.
>> less than a page) region spanning two pages. "region" will be rounded
>> down to the page (iova & PAGE_MASK), but size will only be rounded up to
>> the nearest page. This can miss the start of the second page.
> 
> This is probably redundant. Everything the driver does with memory is
> in units of pages. Maybe imported buffers could be unaligned. Not sure
> and we'd probably break in other places if that was the case.

Yes I don't think this case will occur at the moment. I just noticed it
because the interface was changed from kbase (kbase passes in a page
offset, this version uses a byte offset).

>>> +             /* terminal fault, print info about the fault */
>>> +             dev_err(pfdev->dev,
>>> +                     "Unhandled Page fault in AS%d at VA 0x%016llX\n"
>>> +                     "Reason: %s\n"
>>> +                     "raw fault status: 0x%X\n"
>>> +                     "decoded fault status: %s\n"
>>> +                     "exception type 0x%X: %s\n"
>>> +                     "access type 0x%X: %s\n"
>>> +                     "source id 0x%X\n",
>>> +                     i, addr,
>>> +                     "TODO",
>>> +                     fault_status,
>>> +                     (fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
>>> +                     exception_type, panfrost_exception_name(pfdev, exception_type),
>>> +                     access_type, access_type_name(pfdev, fault_status),
>>> +                     source_id);
>>> +
>>> +             mmu_write(pfdev, MMU_INT_CLEAR, mask);
>>
>> To fully handle the fault you will need to issue an MMU command (i.e.
>> call mmu_hw_do_operation()) - obviously after doing something to fix the
>> cause (e.g. mapping a page or switching the GPU to UNMAPPED mode to kill
>> off the job). Otherwise you may see that the GPU hangs. Although in
>> practice at this stage of the driver the generic timeout is probably the
>> simplest way of handling an MMU fault.
> 
> Any fault currently is unexpected so all we really care about at this
> point is getting a message.

No problem. It will become relevant when you schedule work from multiple
applications at the same time.

[...]
>>
>> This is with the below simple reproducer:
>>
>> ----8<----
>> #include <sys/ioctl.h>
>> #include <fcntl.h>
>> #include <stdio.h>
>>
>> #include <libdrm/drm.h>
>> #include "panfrost_drm.h"
>>
>> int main(int argc, char **argv)
>> {
>>         int fd;
>>
>>         if (argc == 2)
>>                 fd = open(argv[1], O_RDWR);
>>         else
>>                 fd = open("/dev/dri/renderD128", O_RDWR);
>>         if (fd == -1) {
>>                 perror("Failed to open");
>>                 return 0;
>>         }
>>
>>         struct drm_panfrost_submit submit = {
>>                 .jc = 0,
>>         };
>>         return ioctl(fd, DRM_IOCTL_PANFROST_SUBMIT, &submit);
>> }
>> ----8<----
>>
>> Any ideas? I'm not an expert on DRM, so I got somewhat lost!

Interestingly this actually looks similar to this bug for amdgpu:

https://bugs.freedesktop.org/show_bug.cgi?id=109692

There's a patch on there changing the drm scheduler which might be
relevant. I haven't had chance to try it out.

Steve
On 09/04/2019 17:15, Rob Herring wrote:
> On Tue, Apr 9, 2019 at 10:56 AM Tomeu Vizoso <tomeu.vizoso@collabora.com> wrote:
>>
>> On Mon, 8 Apr 2019 at 23:04, Rob Herring <robh@kernel.org> wrote:
>>>
>>> On Fri, Apr 5, 2019 at 7:30 AM Steven Price <steven.price@arm.com> wrote:
>>>>
>>>> On 01/04/2019 08:47, Rob Herring wrote:
>>>>> This adds the initial driver for panfrost which supports Arm Mali
>>>>> Midgard and Bifrost family of GPUs. Currently, only the T860 and
>>>>> T760 Midgard GPUs have been tested.
>>>
>>> [...]
>>>>> +
>>>>> +             if (status & JOB_INT_MASK_ERR(j)) {
>>>>> +                     job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_NOP);
>>>>> +                     job_write(pfdev, JS_COMMAND(j), JS_COMMAND_HARD_STOP_0);
>>>>
>>>> Hard-stopping an already completed job isn't likely to do very much :)
>>>> Also you are using the "_0" version which is only valid when "job chain
>>>> disambiguation" is present.
>>
>> Yeah, guess that can be removed.
> 
> Steven, TBC, are you suggesting removing both lines or leaving
> JS_COMMAND_NOP? I don't think we can ever have a pending job at this
> point as there's no queuing. So the NOP probably isn't needed, but
> doesn't hurt to have it either.

Both lines are redundant and can be removed. But equally neither will
cause any problems.

Writing NOP into the next register is basically only needed if you know
there's a job there which you no longer want to execute.

kbase does this in certain situations. The main one is on a GPU without
command chain disambiguation if you want to kill a particular job
there's a potential race. For example:

 * Submit job A, followed by job B to slot 0. Job A is currently
executing, job B is waiting in the _NEXT registers.

 * Kernel decides it wants to kill job A (it's taking too long, or the
application has quit).

 * Simply executing a JS_COMMAND_HARD_STOP is racy. If job A finishes
just before doing the register write, then it's actually job B that gets
killed (and it's not always safe to just re-execute a killed job).

 * Instead write NOP to JS_COMMAND_NEXT, then check (again) whether the
job currently running is the one you want. When you then HARD_STOP you
either hit the correct job, or 'miss' and do nothing.

Job chain disambiguation solves this problem by allowing the kernel to
tag each job with a flag, the hard-stop can then be targetted at the job
with the correct flag. Writing NOP into JS_COMMAND_NEXT is also useful
if in the above situation you want to kill job B. In that case you can't
hard-stop it (it hasn't start), so you simply want to remove it from the
_NEXT registers.

>>>> I suspect in this case you should also be signalling the fence? At the
>>>> moment you rely on the GPU timeout recovering from the fault.
>>>
>>> I'll defer to Tomeu who wrote this (IIRC).
>>
>> Yes, that would be an improvement.
> 
> Actually, I think that would break recovery because the job timeout
> will bail out if the done fence is signaled already. Perhaps we want
> to timeout immediately if that is possible with the scheduler.

Ideally you would signal the fence with an error code (which is
presumably what recovery does). There's no actual need to trigger a
timeout. I'm not sure quite how the DRM infrastructure handles this though.

Steve
On Wed, 10 Apr 2019 at 12:20, Steven Price <steven.price@arm.com> wrote:
>
> On 08/04/2019 22:04, Rob Herring wrote:
> > On Fri, Apr 5, 2019 at 7:30 AM Steven Price <steven.price@arm.com> wrote:
> >>
> >> On 01/04/2019 08:47, Rob Herring wrote:
> >>> This adds the initial driver for panfrost which supports Arm Mali
> >>> Midgard and Bifrost family of GPUs. Currently, only the T860 and
> >>> T760 Midgard GPUs have been tested.
> >
> > [...]
> >
> >>> +     case 0xD3: return "TRANSTAB_BUS_FAULT_LEVEL3";
> >>> +     case 0xD4: return "TRANSTAB_BUS_FAULT_LEVEL4";
> >>> +     case 0xD8: return "ACCESS_FLAG";
> >>> +     }
> >>> +
> >>> +     if (panfrost_has_hw_feature(pfdev, HW_FEATURE_AARCH64_MMU)) {
> >>
> >> There's not a great deal of point in this conditional - you won't get
> >> the below exception codes from hardware which doesn't support it AARCH64
> >> page tables.
> >
> > I wasn't sure if "UNKNOWN" types could happen or not.
> >
> >>
> >>> +             switch (exception_code) {
> >>> +             case 0xC9 ... 0xCF: return "PERMISSION_FAULT";
> >>> +             case 0xD9 ... 0xDF: return "ACCESS_FLAG";
> >>> +             case 0xE0 ... 0xE7: return "ADDRESS_SIZE_FAULT";
> >>> +             case 0xE8 ... 0xEF: return "MEMORY_ATTRIBUTES_FAULT";
> >>> +             }
> >>> +     }
> >>> +
> >>> +     return "UNKNOWN";
> >>> +}
> >
> >>> +static inline int panfrost_model_cmp(struct panfrost_device *pfdev, s32 id)
> >>> +{
> >>> +     s32 match_id = pfdev->features.id;
> >>> +
> >>> +     if (match_id & 0xf000)
> >>> +             match_id &= 0xf00f;
> >>
> >> I'm puzzled by this, and really not sure if it's going to work out
> >> ignoring the ARCH_MINOR/ARCH_REV fields. But for now there's no real
> >> Bifrost support.
> >
> > That seemed to be enough for kbase to select features/issues.
>
> I can't deny that it seems to work for now, and indeed looking more
> closely at kbase that does seem to be the effect of the current code.
>
> >>> +     switch (param->param) {
> >>> +     case DRM_PANFROST_PARAM_GPU_ID:
> >>> +             param->value = pfdev->features.id;
> >>
> >> This is unfortunate naming - this parameter is *not* the GPU_ID. It is
> >> the top half of the GPU_ID which kbase calls the PRODUCT_ID.
> >
> > I can rename it.
>
> It would help prevent confusion, thanks!
>
> >> I'm also somewhat surprised that you don't need loads of other
> >> properties from the GPU - in particular knowing the number of shader
> >> cores is useful for allocating the right amount of memory for TLS (and
> >> can't be obtained purely from the GPU_ID).
> >
> > We'll add them as userspace needs them.
>
> Fair enough. I'm not sure how much you want to provide "forward
> compatibility" by providing them early - the basic definitions are
> already in kbase. I found it a bit surprising that some feature
> registers are printed on probe, but not available to be queried.
>
> >>> +static int
> >>> +panfrost_lookup_bos(struct drm_device *dev,
> >>> +               struct drm_file *file_priv,
> >>> +               struct drm_panfrost_submit *args,
> >>> +               struct panfrost_job *job)
> >>> +{
> >>> +     u32 *handles;
> >>> +     int ret = 0;
> >>> +
> >>> +     job->bo_count = args->bo_handle_count;
> >>> +
> >>> +     if (!job->bo_count)
> >>> +             return 0;
> >>> +
> >>> +     job->bos = kvmalloc_array(job->bo_count,
> >>> +                               sizeof(struct drm_gem_object *),
> >>> +                               GFP_KERNEL | __GFP_ZERO);
> >>> +     if (!job->bos)
> >>
> >> If we return here then job->bo_count has been set, but job->bos is
> >> invalid - this means that panfrost_job_cleanup() will then dereference
> >> NULL. Although maybe this is better fixed in panfrost_job_cleanup().
> >
> > Good catch. The fence arrays have the same problem. As does V3D which we copied.
> >
> >>> +             return -ENOMEM;
> >>> +
> >>> +     job->implicit_fences = kvmalloc_array(job->bo_count,
> >>> +                               sizeof(struct dma_fence *),
> >>> +                               GFP_KERNEL | __GFP_ZERO);
> >>> +     if (!job->implicit_fences)
> >>> +             return -ENOMEM;
> >
> >>> +static irqreturn_t panfrost_gpu_irq_handler(int irq, void *data)
> >>> +{
> >>> +     struct panfrost_device *pfdev = data;
> >>> +     u32 state = gpu_read(pfdev, GPU_INT_STAT);
> >>> +     u32 fault_status = gpu_read(pfdev, GPU_FAULT_STATUS);
> >>> +     u64 address;
> >>> +     bool done = false;
> >>> +
> >>> +     if (!state)
> >>> +             return IRQ_NONE;
> >>> +
> >>> +     if (state & GPU_IRQ_MASK_ERROR) {
> >>> +             address = (u64) gpu_read(pfdev, GPU_FAULT_ADDRESS_HI) << 32;
> >>> +             address |= gpu_read(pfdev, GPU_FAULT_ADDRESS_LO);
> >>> +
> >>> +             dev_warn(pfdev->dev, "GPU Fault 0x%08x (%s) at 0x%016llx\n",
> >>> +                      fault_status & 0xFF, panfrost_exception_name(pfdev, fault_status),
> >>> +                      address);
> >>> +
> >>> +             if (state & GPU_IRQ_MULTIPLE_FAULT)
> >>> +                     dev_warn(pfdev->dev, "There were multiple GPU faults - some have not been reported\n");
> >>> +
> >>> +             gpu_write(pfdev, GPU_INT_MASK, 0);
> >>
> >> Do you intend to mask off future GPU interrupts?
> >
> > Yes, maybe?
> >
> > If we fault here, then we are going to reset the gpu on timeout which
> > then re-enables interrupts.
>
> Well fair enough. But there's no actual need to force a GPU reset.
> Really there's nothing you can do other than report a GPU fault. kbase
> simply reports it and otherwise ignores it (no GPU reset).
>
> Also will you actually trigger the GPU timeout? This won't mask of the
> JOB completion IRQ, so jobs can still complete.
>
> When you integrate other GPU irq sources (counters/power management)
> then you almost certainly don't want to mask those off just because of a
> GPU fault.
>
> >>> +static irqreturn_t panfrost_job_irq_handler(int irq, void *data)
> >>> +{
> >>> +     struct panfrost_device *pfdev = data;
> >>> +     u32 status = job_read(pfdev, JOB_INT_STAT);
> >>> +     int j;
> >>> +
> >>> +     dev_dbg(pfdev->dev, "jobslot irq status=%x\n", status);
> >>> +
> >>> +     if (!status)
> >>> +             return IRQ_NONE;
> >>> +
> >>> +     pm_runtime_mark_last_busy(pfdev->dev);
> >>> +
> >>> +     for (j = 0; status; j++) {
> >>> +             u32 mask = MK_JS_MASK(j);
> >>> +
> >>> +             if (!(status & mask))
> >>> +                     continue;
> >>> +
> >>> +             job_write(pfdev, JOB_INT_CLEAR, mask);
> >>> +
> >>> +             if (status & JOB_INT_MASK_ERR(j)) {
> >>> +                     job_write(pfdev, JS_COMMAND_NEXT(j), JS_COMMAND_NOP);
> >>> +                     job_write(pfdev, JS_COMMAND(j), JS_COMMAND_HARD_STOP_0);
> >>
> >> Hard-stopping an already completed job isn't likely to do very much :)
> >> Also you are using the "_0" version which is only valid when "job chain
> >> disambiguation" is present.
> >>
> >> I suspect in this case you should also be signalling the fence? At the
> >> moment you rely on the GPU timeout recovering from the fault.
> >
> > I'll defer to Tomeu who wrote this (IIRC).
> >
> >
> >>> +static void lock_region(struct panfrost_device *pfdev, u32 as_nr,
> >>> +                     u64 iova, size_t size)
> >>> +{
> >>> +     u8 region_width;
> >>> +     u64 region = iova & PAGE_MASK;
> >>> +     /*
> >>> +      * fls returns (given the ASSERT above):
> >>
> >> But where's the assert? :p
> >>
> >>> +      * 1 .. 32
> >>> +      *
> >>> +      * 10 + fls(num_pages)
> >>> +      * results in the range (11 .. 42)
> >>> +      */
> >>> +
> >>> +     size = round_up(size, PAGE_SIZE);
> >>
> >> I'm not sure it matters, but this will break if called on a (small, i.e.
> >> less than a page) region spanning two pages. "region" will be rounded
> >> down to the page (iova & PAGE_MASK), but size will only be rounded up to
> >> the nearest page. This can miss the start of the second page.
> >
> > This is probably redundant. Everything the driver does with memory is
> > in units of pages. Maybe imported buffers could be unaligned. Not sure
> > and we'd probably break in other places if that was the case.
>
> Yes I don't think this case will occur at the moment. I just noticed it
> because the interface was changed from kbase (kbase passes in a page
> offset, this version uses a byte offset).
>
> >>> +             /* terminal fault, print info about the fault */
> >>> +             dev_err(pfdev->dev,
> >>> +                     "Unhandled Page fault in AS%d at VA 0x%016llX\n"
> >>> +                     "Reason: %s\n"
> >>> +                     "raw fault status: 0x%X\n"
> >>> +                     "decoded fault status: %s\n"
> >>> +                     "exception type 0x%X: %s\n"
> >>> +                     "access type 0x%X: %s\n"
> >>> +                     "source id 0x%X\n",
> >>> +                     i, addr,
> >>> +                     "TODO",
> >>> +                     fault_status,
> >>> +                     (fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
> >>> +                     exception_type, panfrost_exception_name(pfdev, exception_type),
> >>> +                     access_type, access_type_name(pfdev, fault_status),
> >>> +                     source_id);
> >>> +
> >>> +             mmu_write(pfdev, MMU_INT_CLEAR, mask);
> >>
> >> To fully handle the fault you will need to issue an MMU command (i.e.
> >> call mmu_hw_do_operation()) - obviously after doing something to fix the
> >> cause (e.g. mapping a page or switching the GPU to UNMAPPED mode to kill
> >> off the job). Otherwise you may see that the GPU hangs. Although in
> >> practice at this stage of the driver the generic timeout is probably the
> >> simplest way of handling an MMU fault.
> >
> > Any fault currently is unexpected so all we really care about at this
> > point is getting a message.
>
> No problem. It will become relevant when you schedule work from multiple
> applications at the same time.
>
> [...]
> >>
> >> This is with the below simple reproducer:
> >>
> >> ----8<----
> >> #include <sys/ioctl.h>
> >> #include <fcntl.h>
> >> #include <stdio.h>
> >>
> >> #include <libdrm/drm.h>
> >> #include "panfrost_drm.h"
> >>
> >> int main(int argc, char **argv)
> >> {
> >>         int fd;
> >>
> >>         if (argc == 2)
> >>                 fd = open(argv[1], O_RDWR);
> >>         else
> >>                 fd = open("/dev/dri/renderD128", O_RDWR);
> >>         if (fd == -1) {
> >>                 perror("Failed to open");
> >>                 return 0;
> >>         }
> >>
> >>         struct drm_panfrost_submit submit = {
> >>                 .jc = 0,
> >>         };
> >>         return ioctl(fd, DRM_IOCTL_PANFROST_SUBMIT, &submit);
> >> }
> >> ----8<----
> >>
> >> Any ideas? I'm not an expert on DRM, so I got somewhat lost!
>
> Interestingly this actually looks similar to this bug for amdgpu:
>
> https://bugs.freedesktop.org/show_bug.cgi?id=109692
>
> There's a patch on there changing the drm scheduler which might be
> relevant. I haven't had chance to try it out.

Seems indeed to be the case, and I guess all drivers using gpu-sched
have the same problem.

There's ongoing discussions on the fix for it, so I will leave it be for now.

Thanks for the pointer!

Tomeu
On Fri, Apr 05, 2019 at 05:42:33PM +0100, Steven Price wrote:
> On 05/04/2019 17:16, Alyssa Rosenzweig wrote:
> > acronym once ever and have it as a "??"), I'm not sure how to respond to
> > that... We don't know how to allocate memory for the GPU-internal data
> > structures (the tiler heap, for instance, but also a few others I've
> > just named "misc_0" and "scratchpad" -- guessing one of those is for
> > "TLS"). With kbase, I took the worst-case strategy of allocating
> > gigantic chunks on startup with tiny commit counts and GROW_ON_GPF set.
> > With the new driver, well, our memory consumption is scary since
> > implementing GROW_ON_GPF in an upstream-friendly way is a bit more work
> > and isn't expected to hit the 5.2 window.
> 
> Yes GROW_ON_GPF is pretty much required for the tiler heap - it's not
> (reasonably) possible to determine how big it should be. The Arm user
> space driver does the same approach (tiny commit count, but allow it to
> grow).

Jumping in here with a drive through comment ...

Growing gem bo and dma-buf is going to be endless amounts of fun, since we
hard-coded that their size is invariant.

I think the only reasonable way to implement this is if you allocate a
really huge bo, map it, but only put the pages in on faulting. Or when
really evil userspace tries to export it. Actually changing the underlying
buffer size is not going to work I think.

Note: I didn't read kbase, so might be totally wrong in how GROW_ON_GPF
works.
-Daniel
On 15/04/2019 10:18, Daniel Vetter wrote:
> On Fri, Apr 05, 2019 at 05:42:33PM +0100, Steven Price wrote:
>> On 05/04/2019 17:16, Alyssa Rosenzweig wrote:
>>> acronym once ever and have it as a "??"), I'm not sure how to respond to
>>> that... We don't know how to allocate memory for the GPU-internal data
>>> structures (the tiler heap, for instance, but also a few others I've
>>> just named "misc_0" and "scratchpad" -- guessing one of those is for
>>> "TLS"). With kbase, I took the worst-case strategy of allocating
>>> gigantic chunks on startup with tiny commit counts and GROW_ON_GPF set.
>>> With the new driver, well, our memory consumption is scary since
>>> implementing GROW_ON_GPF in an upstream-friendly way is a bit more work
>>> and isn't expected to hit the 5.2 window.
>>
>> Yes GROW_ON_GPF is pretty much required for the tiler heap - it's not
>> (reasonably) possible to determine how big it should be. The Arm user
>> space driver does the same approach (tiny commit count, but allow it to
>> grow).
> 
> Jumping in here with a drive through comment ...
> 
> Growing gem bo and dma-buf is going to be endless amounts of fun, since we
> hard-coded that their size is invariant.
> 
> I think the only reasonable way to implement this is if you allocate a
> really huge bo, map it, but only put the pages in on faulting. Or when
> really evil userspace tries to export it. Actually changing the underlying
> buffer size is not going to work I think.

Yes the idea is that you allocate a large amount of virtual address
space, but only put a few physical pages in. If the GPU needs more you
fault them in as necessary. The "buffer size" (i.e. virtual address
region) never changes size.

> Note: I didn't read kbase, so might be totally wrong in how GROW_ON_GPF
> works.

For kbase we simply don't support exporting this type of memory, and are
fairly restrictive about mapping it into user space (user space
shouldn't normally need to read it).

Since Panfrost is using GEM BO it will have to deal with malicious user
space. But it would be sufficient to simply fully back the region in
that case.

Recent version of kbase also support what is termed JIT (Just In Time
memory allocation). Basically this involves the kernel driver
allocating/freeing memory regions just before the job is loaded onto the
GPU. These regions might also be GROW_ON_GPF. The intention is that when
there isn't memory pressure these regions can be kept between jobs, but
under memory pressure they can be discarded and recreated if they turn
out to be needed again.

Given the differences between the Panfrost and the proprietary user
space I'm not sure exactly what form this will need to be for Panfrost,
but Vulkan makes memory management "more interesting"! Allocating
upfront for the worst case can become prohibitively expensive.

Steve
On Mon, Apr 15, 2019 at 10:30:14AM +0100, Steven Price wrote:
> On 15/04/2019 10:18, Daniel Vetter wrote:
> > On Fri, Apr 05, 2019 at 05:42:33PM +0100, Steven Price wrote:
> >> On 05/04/2019 17:16, Alyssa Rosenzweig wrote:
> >>> acronym once ever and have it as a "??"), I'm not sure how to respond to
> >>> that... We don't know how to allocate memory for the GPU-internal data
> >>> structures (the tiler heap, for instance, but also a few others I've
> >>> just named "misc_0" and "scratchpad" -- guessing one of those is for
> >>> "TLS"). With kbase, I took the worst-case strategy of allocating
> >>> gigantic chunks on startup with tiny commit counts and GROW_ON_GPF set.
> >>> With the new driver, well, our memory consumption is scary since
> >>> implementing GROW_ON_GPF in an upstream-friendly way is a bit more work
> >>> and isn't expected to hit the 5.2 window.
> >>
> >> Yes GROW_ON_GPF is pretty much required for the tiler heap - it's not
> >> (reasonably) possible to determine how big it should be. The Arm user
> >> space driver does the same approach (tiny commit count, but allow it to
> >> grow).
> > 
> > Jumping in here with a drive through comment ...
> > 
> > Growing gem bo and dma-buf is going to be endless amounts of fun, since we
> > hard-coded that their size is invariant.
> > 
> > I think the only reasonable way to implement this is if you allocate a
> > really huge bo, map it, but only put the pages in on faulting. Or when
> > really evil userspace tries to export it. Actually changing the underlying
> > buffer size is not going to work I think.
> 
> Yes the idea is that you allocate a large amount of virtual address
> space, but only put a few physical pages in. If the GPU needs more you
> fault them in as necessary. The "buffer size" (i.e. virtual address
> region) never changes size.
> 
> > Note: I didn't read kbase, so might be totally wrong in how GROW_ON_GPF
> > works.
> 
> For kbase we simply don't support exporting this type of memory, and are
> fairly restrictive about mapping it into user space (user space
> shouldn't normally need to read it).

You can still disallow sharing with any other driver (in the dma-buf
attach callback), and then enforce whatever mapping restrictions you want
on the panfrost.ko ioctl interface. That should be roughly equivalent to
the restrictions kbase imposes.
> 
> Since Panfrost is using GEM BO it will have to deal with malicious user
> space. But it would be sufficient to simply fully back the region in
> that case.
> 
> Recent version of kbase also support what is termed JIT (Just In Time
> memory allocation). Basically this involves the kernel driver
> allocating/freeing memory regions just before the job is loaded onto the
> GPU. These regions might also be GROW_ON_GPF. The intention is that when
> there isn't memory pressure these regions can be kept between jobs, but
> under memory pressure they can be discarded and recreated if they turn
> out to be needed again.
> 
> Given the differences between the Panfrost and the proprietary user
> space I'm not sure exactly what form this will need to be for Panfrost,
> but Vulkan makes memory management "more interesting"! Allocating
> upfront for the worst case can become prohibitively expensive.

The usual way to do that is with a WONTNEED/WILLNEED madvise ioctl on the
gem bo. I guess that could also be set at create time to essentially only
require the bo to exist during an execbuf call. Should fit pretty well
into what other drivers are doing with gem shmem already I think.

ofc needs a shrinker to be able to reap these bo.
-Daniel