[i-g-t] tests: Add variable refresh rate tests

Submitted by Kazlauskas, Nicholas on Jan. 9, 2019, 7:49 p.m.

Details

Message ID 20190109194932.16679-1-nicholas.kazlauskas@amd.com
State New
Series "tests: Add variable refresh rate tests"
Headers show

Commit Message

Kazlauskas, Nicholas Jan. 9, 2019, 7:49 p.m.
There are 3 tests for basic variable refresh rate functionality.

The tests measure flipping at the midpoint between the current mode's
refresh rate and the minimum supported variable refresh rate.

It tests that VRR is enabled and that the difference between flip
timestamps converges to the requested rate. It also tests this under
both S3 and DPMS.

Potential ideas for future tests:
- Test behavior inside VRR range with a stepping test
- Test behavior outside of VRR range
- Multi-monitor (limited by no async pageflips in DRM atomic API)

Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Leo Li <sunpeng.li@amd.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
---
 lib/igt_kms.c          |   3 +
 lib/igt_kms.h          |   2 +
 tests/Makefile.sources |   1 +
 tests/kms_vrr.c        | 417 +++++++++++++++++++++++++++++++++++++++++
 tests/meson.build      |   1 +
 5 files changed, 424 insertions(+)
 create mode 100644 tests/kms_vrr.c

Patch hide | download patch | download mbox

diff --git a/lib/igt_kms.c b/lib/igt_kms.c
index 684a599c..2edf19ec 100644
--- a/lib/igt_kms.c
+++ b/lib/igt_kms.c
@@ -189,6 +189,7 @@  const char * const igt_crtc_prop_names[IGT_NUM_CRTC_PROPS] = {
 	[IGT_CRTC_MODE_ID] = "MODE_ID",
 	[IGT_CRTC_ACTIVE] = "ACTIVE",
 	[IGT_CRTC_OUT_FENCE_PTR] = "OUT_FENCE_PTR",
+	[IGT_CRTC_VRR_ENABLED] = "VRR_ENABLED",
 };
 
 const char * const igt_connector_prop_names[IGT_NUM_CONNECTOR_PROPS] = {
@@ -197,6 +198,7 @@  const char * const igt_connector_prop_names[IGT_NUM_CONNECTOR_PROPS] = {
 	[IGT_CONNECTOR_DPMS] = "DPMS",
 	[IGT_CONNECTOR_BROADCAST_RGB] = "Broadcast RGB",
 	[IGT_CONNECTOR_CONTENT_PROTECTION] = "Content Protection",
+	[IGT_CONNECTOR_VRR_CAPABLE] = "vrr_capable",
 };
 
 /*
@@ -1786,6 +1788,7 @@  static void igt_pipe_reset(igt_pipe_t *pipe)
 {
 	igt_pipe_obj_set_prop_value(pipe, IGT_CRTC_MODE_ID, 0);
 	igt_pipe_obj_set_prop_value(pipe, IGT_CRTC_ACTIVE, 0);
+	igt_pipe_obj_set_prop_value(pipe, IGT_CRTC_VRR_ENABLED, 0);
 	igt_pipe_obj_clear_prop_changed(pipe, IGT_CRTC_OUT_FENCE_PTR);
 
 	pipe->out_fence_fd = -1;
diff --git a/lib/igt_kms.h b/lib/igt_kms.h
index 4a7c3c97..679d4e84 100644
--- a/lib/igt_kms.h
+++ b/lib/igt_kms.h
@@ -104,6 +104,7 @@  enum igt_atomic_crtc_properties {
        IGT_CRTC_MODE_ID,
        IGT_CRTC_ACTIVE,
        IGT_CRTC_OUT_FENCE_PTR,
+       IGT_CRTC_VRR_ENABLED,
        IGT_NUM_CRTC_PROPS
 };
 
@@ -121,6 +122,7 @@  enum igt_atomic_connector_properties {
        IGT_CONNECTOR_DPMS,
        IGT_CONNECTOR_BROADCAST_RGB,
        IGT_CONNECTOR_CONTENT_PROTECTION,
+       IGT_CONNECTOR_VRR_CAPABLE,
        IGT_NUM_CONNECTOR_PROPS
 };
 
diff --git a/tests/Makefile.sources b/tests/Makefile.sources
index baac7ae0..239bed59 100644
--- a/tests/Makefile.sources
+++ b/tests/Makefile.sources
@@ -88,6 +88,7 @@  TESTS_progs = \
 	kms_tv_load_detect \
 	kms_universal_plane \
 	kms_vblank \
+	kms_vrr \
 	kms_sequence \
 	meta_test \
 	perf \
diff --git a/tests/kms_vrr.c b/tests/kms_vrr.c
new file mode 100644
index 00000000..c6b88e53
--- /dev/null
+++ b/tests/kms_vrr.c
@@ -0,0 +1,417 @@ 
+/*
+ * Copyright 2018 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "igt.h"
+#include "sw_sync.h"
+#include <fcntl.h>
+#include <signal.h>
+
+#define NSECS_PER_SEC (1000000000ull)
+
+/*
+ * Each test measurement step runs for ~5 seconds.
+ * This gives a decent sample size + enough time for any adaptation to occur if necessary.
+ */
+#define TEST_DURATION_NS (5000000000ull)
+
+enum {
+	TEST_NONE = 0,
+	TEST_DPMS = 1 << 0,
+	TEST_SUSPEND = 1 << 1,
+};
+
+typedef struct range {
+	unsigned int min;
+	unsigned int max;
+} range_t;
+
+typedef struct data {
+	igt_display_t display;
+	int drm_fd;
+	igt_fb_t fb0;
+	igt_fb_t fb1;
+} data_t;
+
+typedef void (*test_t)(data_t*, enum pipe, igt_output_t*, uint32_t);
+
+/* Converts a timespec structure to nanoseconds. */
+static uint64_t timespec_to_ns(struct timespec *ts)
+{
+	return ts->tv_sec * NSECS_PER_SEC + ts->tv_nsec;
+}
+
+/*
+ * Gets a vblank event from DRM and returns its timestamp in nanoseconds.
+ * This blocks until the event is received.
+ */
+static uint64_t get_vblank_event_ns(data_t *data)
+{
+	struct drm_event_vblank ev;
+
+	igt_set_timeout(1, "Waiting for vblank event\n");
+	igt_assert_eq(read(data->drm_fd, &ev, sizeof(ev)), sizeof(ev));
+	igt_reset_timeout();
+
+	return ev.tv_sec * NSECS_PER_SEC + ev.tv_usec * 1000ull;
+}
+
+/*
+ * Returns the current CLOCK_MONOTONIC time in nanoseconds.
+ * The regular IGT helpers can't be used since they default to
+ * CLOCK_MONOTONIC_RAW - which isn't what the kernel uses for its timestamps.
+ */
+static uint64_t get_time_ns(void)
+{
+	struct timespec ts;
+	memset(&ts, 0, sizeof(ts));
+	errno = 0;
+
+	if (!clock_gettime(CLOCK_MONOTONIC, &ts))
+		return timespec_to_ns(&ts);
+
+	igt_warn("Could not read monotonic time: %s\n", strerror(errno));
+	igt_fail(-errno);
+
+	return 0;
+}
+
+/* Returns the rate duration in nanoseconds for the given refresh rate. */
+static uint64_t rate_from_refresh(uint64_t refresh)
+{
+	return NSECS_PER_SEC / refresh;
+}
+
+/* Returns the min and max vrr range from the connector debugfs. */
+static range_t get_vrr_range(data_t *data, igt_output_t *output)
+{
+	char buf[256];
+	char *start_loc;
+	int fd, res;
+	range_t range;
+
+	fd = igt_debugfs_connector_dir(data->drm_fd, output->name, O_RDONLY);
+	igt_assert(fd >= 0);
+
+	res = igt_debugfs_simple_read(fd, "vrr_range", buf, sizeof(buf));
+	igt_require(res > 0);
+
+	close(fd);
+
+	igt_assert(start_loc = strstr(buf, "Min: "));
+	igt_assert_eq(sscanf(start_loc, "Min: %u", &range.min), 1);
+
+	igt_assert(start_loc = strstr(buf, "Max: "));
+	igt_assert_eq(sscanf(start_loc, "Max: %u", &range.max), 1);
+
+	return range;
+}
+
+/* Returns a suitable vrr test frequency. */
+static uint32_t get_test_rate_ns(data_t *data, igt_output_t *output)
+{
+	drmModeModeInfo *mode = igt_output_get_mode(output);
+	range_t range;
+	uint32_t vtest;
+
+	/*
+	 * The frequency with the fastest convergence speed should be
+	 * the midpoint between the current mode vfreq and the min
+	 * supported vfreq.
+	 */
+	range = get_vrr_range(data, output);
+	igt_require(mode->vrefresh > range.min);
+
+	vtest = (mode->vrefresh - range.min) / 2 + range.min;
+	igt_require(vtest < mode->vrefresh);
+
+	return rate_from_refresh(vtest);
+}
+
+/* Returns true if an output supports VRR. */
+static bool has_vrr(igt_output_t *output)
+{
+	return igt_output_has_prop(output, IGT_CONNECTOR_VRR_CAPABLE) &&
+	       igt_output_get_prop(output, IGT_CONNECTOR_VRR_CAPABLE);
+}
+
+/* Toggles variable refresh rate on the pipe. */
+static void set_vrr_on_pipe(data_t *data, enum pipe pipe, bool enabled)
+{
+	igt_pipe_set_prop_value(&data->display, pipe, IGT_CRTC_VRR_ENABLED,
+				enabled);
+	igt_display_commit_atomic(&data->display, 0, NULL);
+}
+
+/* Prepare the display for testing on the given pipe. */
+static void prepare_test(data_t *data, igt_output_t *output, enum pipe pipe)
+{
+	drmModeModeInfo mode = *igt_output_get_mode(output);
+	igt_plane_t *primary;
+	cairo_t *cr;
+
+	/* Reset output */
+	igt_display_reset(&data->display);
+	igt_output_set_pipe(output, pipe);
+
+	/* Prepare resources */
+	igt_remove_fb(data->drm_fd, &data->fb1);
+	igt_remove_fb(data->drm_fd, &data->fb0);
+
+	igt_create_color_fb(data->drm_fd, mode.hdisplay, mode.vdisplay,
+			    DRM_FORMAT_XRGB8888, LOCAL_DRM_FORMAT_MOD_NONE,
+			    0.50, 0.50, 0.50, &data->fb0);
+
+	igt_create_color_fb(data->drm_fd, mode.hdisplay, mode.vdisplay,
+			    DRM_FORMAT_XRGB8888, LOCAL_DRM_FORMAT_MOD_NONE,
+			    0.50, 0.50, 0.50, &data->fb1);
+
+	cr = igt_get_cairo_ctx(data->drm_fd, &data->fb0);
+
+	igt_paint_color(cr, 0, 0, mode.hdisplay / 10, mode.vdisplay / 10,
+			1.00, 0.00, 0.00);
+
+	/* Take care of any required modesetting before the test begins. */
+	primary = igt_output_get_plane_type(output, DRM_PLANE_TYPE_PRIMARY);
+	igt_plane_set_fb(primary, &data->fb0);
+
+	igt_display_commit_atomic(&data->display,
+				  DRM_MODE_ATOMIC_ALLOW_MODESET, NULL);
+}
+
+/* Waits for the vblank interval. Returns the vblank timestamp in ns. */
+static uint64_t
+wait_for_vblank(data_t *data, enum pipe pipe)
+{
+	drmVBlank vbl = { 0 };
+
+	vbl.request.type = kmstest_get_vbl_flag(pipe);
+	vbl.request.type |= DRM_VBLANK_RELATIVE | DRM_VBLANK_EVENT;
+	vbl.request.sequence = 1;
+	drmWaitVBlank(data->drm_fd, &vbl);
+
+	return get_vblank_event_ns(data);
+}
+
+/* Performs an asynchronous non-blocking page-flip on a pipe. */
+static int
+do_flip(data_t *data, enum pipe pipe_id, igt_fb_t *fb)
+{
+	igt_pipe_t *pipe = &data->display.pipes[pipe_id];
+	int ret;
+
+	igt_set_timeout(1, "Scheduling page flip\n");
+
+	/*
+	 * Only the legacy flip ioctl supports async flips.
+	 * It's also non-blocking, but returns -EBUSY if flipping too fast.
+	 * 2x monitor tests will need async flips in the atomic API.
+	 */
+	do {
+		ret = drmModePageFlip(data->drm_fd, pipe->crtc_id,
+				      fb->fb_id,
+				      DRM_MODE_PAGE_FLIP_EVENT |
+				      DRM_MODE_PAGE_FLIP_ASYNC,
+				      data);
+	} while (ret == -EBUSY);
+
+	igt_assert_eq(ret, 0);
+	igt_reset_timeout();
+
+	return 0;
+}
+
+/*
+ * Flips at the given rate and measures against the expected value.
+ * Returns the pass rate as a percentage from 0 - 100.
+ *
+ * The VRR API is quite flexible in terms of definition - the driver
+ * can arbitrarily restrict the bounds further than the absolute
+ * min and max range. But VRR is really about extending the flip
+ * to prevent stuttering or to match a source content rate.
+ *
+ * The only way to "present" at a fixed rate like userspace in a vendor
+ * neutral manner is to do it with async flips. This avoids the need
+ * to wait for next vblank and it should eventually converge at the
+ * desired rate.
+ */
+static uint32_t
+flip_and_measure(data_t *data, igt_output_t *output, enum pipe pipe,
+		 uint64_t rate_ns, uint64_t duration_ns)
+{
+	uint64_t start_ns, last_vblank_ns;
+	uint32_t total_flip = 0, total_pass = 0;
+	bool front = false;
+
+	/* Align with the vblank region to speed up convergence. */
+	last_vblank_ns = wait_for_vblank(data, pipe);
+	start_ns = get_time_ns();
+
+	for (;;) {
+		uint64_t now_ns, vblank_ns, wait_ns, target_ns;
+		int64_t diff_ns;
+
+		front = !front;
+		do_flip(data, pipe, front ? &data->fb1 : &data->fb0);
+
+		vblank_ns = get_vblank_event_ns(data);
+		diff_ns = rate_ns - (vblank_ns - last_vblank_ns);
+		last_vblank_ns = vblank_ns;
+
+		total_flip += 1;
+
+		/*
+		 * Check if the difference between the two flip timestamps
+		 * was within the required threshold from the expected rate.
+		 *
+		 * A ~50us threshold is arbitrary, but it's roughly the
+		 * difference between 144Hz and 143Hz which should give this
+		 * enough accuracy for most use cases.
+		 */
+		if (llabs(diff_ns) < 50000ll)
+			total_pass += 1;
+
+		now_ns = get_time_ns();
+		if (now_ns - start_ns > duration_ns)
+			break;
+
+		/*
+		 * Burn CPU until next timestamp, sleeping isn't accurate enough.
+		 * It's worth noting that the target timestamp is based on absolute
+		 * timestamp rather than a delta to avoid accumulation errors.
+		 */
+		diff_ns = now_ns - start_ns;
+		wait_ns = ((diff_ns + rate_ns - 1) / rate_ns) * rate_ns;
+		target_ns = start_ns + wait_ns - 10;
+
+		while (get_time_ns() < target_ns);
+	}
+
+	igt_info("Completed %u flips, %u were in threshold for %luns.\n",
+		 total_flip, total_pass, rate_ns);
+
+	return total_flip ? ((total_pass * 100) / total_flip) : 0;
+}
+
+/* Basic VRR flip functionality test - enable, measure, disable, measure */
+static void
+test_basic(data_t *data, enum pipe pipe, igt_output_t *output, uint32_t flags)
+{
+	uint64_t rate;
+	uint32_t result;
+
+	rate = get_test_rate_ns(data, output);
+
+	prepare_test(data, output, pipe);
+
+	set_vrr_on_pipe(data, pipe, 1);
+
+	/*
+	 * Do a short run with VRR, but don't check the result.
+	 * This is to make sure we were actually in the middle of
+	 * active flipping before doing the DPMS/suspend steps.
+	 */
+	flip_and_measure(data, output, pipe, rate, 250000000ull);
+
+	if (flags & TEST_DPMS) {
+		kmstest_set_connector_dpms(output->display->drm_fd,
+					   output->config.connector,
+					   DRM_MODE_DPMS_OFF);
+		kmstest_set_connector_dpms(output->display->drm_fd,
+					   output->config.connector,
+					   DRM_MODE_DPMS_ON);
+	}
+
+	if (flags & TEST_SUSPEND)
+		igt_system_suspend_autoresume(SUSPEND_STATE_MEM,
+					      SUSPEND_TEST_NONE);
+
+	result = flip_and_measure(data, output, pipe, rate, TEST_DURATION_NS);
+
+	set_vrr_on_pipe(data, pipe, 0);
+
+	/* This check is delayed until after VRR is disabled so it isn't
+	 * left enabled if the test fails. */
+	igt_assert_f(result > 75,
+		     "Target VRR on threshold not reached, result was %u%%\n",
+		     result);
+
+	result = flip_and_measure(data, output, pipe, rate, TEST_DURATION_NS);
+
+	igt_assert_f(result < 10,
+		     "Target VRR off threshold exceeded, result was %u%%\n",
+		     result);
+}
+
+/* Runs tests on outputs that are VRR capable. */
+static void
+run_vrr_test(data_t *data, test_t test, uint32_t flags)
+{
+	igt_output_t *output;
+	bool found = false;
+
+	for_each_connected_output(&data->display, output) {
+		enum pipe pipe;
+
+		if (!has_vrr(output))
+			continue;
+
+		for_each_pipe(&data->display, pipe)
+			if (igt_pipe_connector_valid(pipe, output)) {
+				test(data, pipe, output, flags);
+				found = true;
+				break;
+			}
+	}
+
+	if (!found)
+		igt_skip("No vrr capable outputs found.\n");
+}
+
+igt_main
+{
+	data_t data = { 0 };
+
+	igt_skip_on_simulation();
+
+	igt_fixture {
+		data.drm_fd = drm_open_driver_master(DRIVER_ANY);
+
+		kmstest_set_vt_graphics_mode();
+
+		igt_display_require(&data.display, data.drm_fd);
+		igt_require(data.display.is_atomic);
+		igt_display_require_output(&data.display);
+	}
+
+	igt_subtest("flip-basic")
+		run_vrr_test(&data, test_basic, 0);
+
+	igt_subtest("flip-dpms")
+		run_vrr_test(&data, test_basic, TEST_DPMS);
+
+	igt_subtest("flip-suspend")
+		run_vrr_test(&data, test_basic, TEST_SUSPEND);
+
+	igt_fixture {
+		igt_display_fini(&data.display);
+	}
+}
diff --git a/tests/meson.build b/tests/meson.build
index b8a6e61b..e887f131 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -59,6 +59,7 @@  test_progs = [
 	'kms_tv_load_detect',
 	'kms_universal_plane',
 	'kms_vblank',
+	'kms_vrr',
 	'meta_test',
 	'perf',
 	'pm_backlight',