[v8,4/6] x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 30h-3fh) Processors v4

Submitted by Christian König on July 10, 2017, 2:59 p.m.

Details

Message ID 1499698794-1718-5-git-send-email-deathsimple@vodafone.de
State New
Headers show
Series "Series without cover letter" ( rev: 1 ) in AMD X.Org drivers

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Commit Message

Christian König July 10, 2017, 2:59 p.m.
From: Christian König <christian.koenig@amd.com>

Most BIOS don't enable this because of compatibility reasons.

Manually enable a 64bit BAR of 64GB size so that we have
enough room for PCI devices.

v2: style cleanups, increase size, add resource name, set correct flags,
    print message that windows was added
v3: add defines for all the magic numbers, style cleanups
v4: add some comment that the BIOS should actually allow this using
    _PRS and _SRS.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
 arch/x86/pci/fixup.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 76 insertions(+)

Patch hide | download patch | download mbox

diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c
index 11e4074..0f4088b 100644
--- a/arch/x86/pci/fixup.c
+++ b/arch/x86/pci/fixup.c
@@ -618,3 +618,79 @@  static void quirk_apple_mbp_poweroff(struct pci_dev *pdev)
 		dev_info(dev, "can't work around MacBook Pro poweroff issue\n");
 }
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x8c10, quirk_apple_mbp_poweroff);
+
+#define AMD_141b_MMIO_BASE(x)	(0x80 + (x) * 0x8)
+#define AMD_141b_MMIO_BASE_RE_MASK		BIT(0)
+#define AMD_141b_MMIO_BASE_WE_MASK		BIT(1)
+#define AMD_141b_MMIO_BASE_MMIOBASE_MASK	GENMASK(31,8)
+
+#define AMD_141b_MMIO_LIMIT(x)	(0x84 + (x) * 0x8)
+#define AMD_141b_MMIO_LIMIT_MMIOLIMIT_MASK	GENMASK(31,8)
+
+#define AMD_141b_MMIO_HIGH(x)	(0x180 + (x) * 0x4)
+#define AMD_141b_MMIO_HIGH_MMIOBASE_MASK	GENMASK(7,0)
+#define AMD_141b_MMIO_HIGH_MMIOLIMIT_SHIFT	16
+#define AMD_141b_MMIO_HIGH_MMIOLIMIT_MASK	GENMASK(23,16)
+
+/*
+ * The PCI Firmware Spec, rev 3.2 notes that ACPI should optionally allow
+ * configuring host bridge windows using the _PRS and _SRS methods.
+ *
+ * But this is rarely implemented, so we manually enable a large 64bit BAR for
+ * PCIe device on AMD Family 15h (Models 30h-3fh) Processors here.
+ */
+static void pci_amd_enable_64bit_bar(struct pci_dev *dev)
+{
+	struct resource *res, *conflict;
+	u32 base, limit, high;
+	unsigned i;
+
+	for (i = 0; i < 8; ++i) {
+		pci_read_config_dword(dev, AMD_141b_MMIO_BASE(i), &base);
+		pci_read_config_dword(dev, AMD_141b_MMIO_HIGH(i), &high);
+
+		/* Is this slot free? */
+		if (!(base & (AMD_141b_MMIO_BASE_RE_MASK |
+			      AMD_141b_MMIO_BASE_WE_MASK)))
+			break;
+
+		base >>= 8;
+		base |= high << 24;
+
+		/* Abort if a slot already configures a 64bit BAR. */
+		if (base > 0x10000)
+			return;
+	}
+	if (i == 8)
+		return;
+
+	res = kzalloc(sizeof(*res), GFP_KERNEL);
+	if (!res)
+		return;
+
+	res->name = "PCI Bus 0000:00";
+	res->flags = IORESOURCE_PREFETCH | IORESOURCE_MEM |
+		IORESOURCE_MEM_64 | IORESOURCE_WINDOW;
+	res->start = 0x100000000ull;
+	res->end = 0xfd00000000ull - 1;
+
+	/* Just grab the free area behind system memory for this */
+	while ((conflict = request_resource_conflict(&iomem_resource, res)))
+		res->start = conflict->end + 1;
+
+	dev_info(&dev->dev, "adding root bus resource %pR\n", res);
+
+	base = ((res->start >> 8) & AMD_141b_MMIO_BASE_MMIOBASE_MASK) |
+		AMD_141b_MMIO_BASE_RE_MASK | AMD_141b_MMIO_BASE_WE_MASK;
+	limit = ((res->end + 1) >> 8) & AMD_141b_MMIO_LIMIT_MMIOLIMIT_MASK;
+	high = ((res->start >> 40) & AMD_141b_MMIO_HIGH_MMIOBASE_MASK) |
+		((((res->end + 1) >> 40) << AMD_141b_MMIO_HIGH_MMIOLIMIT_SHIFT)
+		 & AMD_141b_MMIO_HIGH_MMIOLIMIT_MASK);
+
+	pci_write_config_dword(dev, AMD_141b_MMIO_HIGH(i), high);
+	pci_write_config_dword(dev, AMD_141b_MMIO_LIMIT(i), limit);
+	pci_write_config_dword(dev, AMD_141b_MMIO_BASE(i), base);
+
+	pci_bus_add_resource(dev->bus, res, 0);
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_AMD, 0x141b, pci_amd_enable_64bit_bar);

Comments

Hi Christian,

[auto build test WARNING on pci/next]
[also build test WARNING on next-20170710]
[cannot apply to v4.12]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Christian-K-nig/PCI-add-a-define-for-the-PCI-resource-type-mask-v2/20170711-104904
base:   https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git next
config: i386-allmodconfig (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All warnings (new ones prefixed by >>):

   arch/x86/pci/fixup.c: In function 'pci_amd_enable_64bit_bar':
>> arch/x86/pci/fixup.c:674:15: warning: large integer implicitly truncated to unsigned type [-Woverflow]
     res->start = 0x100000000ull;
                  ^~~~~~~~~~~~~~
   arch/x86/pci/fixup.c:675:13: warning: large integer implicitly truncated to unsigned type [-Woverflow]
     res->end = 0xfd00000000ull - 1;
                ^~~~~~~~~~~~~~~
>> arch/x86/pci/fixup.c:686:22: warning: right shift count >= width of type [-Wshift-count-overflow]
     high = ((res->start >> 40) & AMD_141b_MMIO_HIGH_MMIOBASE_MASK) |
                         ^~
   arch/x86/pci/fixup.c:687:21: warning: right shift count >= width of type [-Wshift-count-overflow]
      ((((res->end + 1) >> 40) << AMD_141b_MMIO_HIGH_MMIOLIMIT_SHIFT)
                        ^~

vim +674 arch/x86/pci/fixup.c

   634	
   635	/*
   636	 * The PCI Firmware Spec, rev 3.2 notes that ACPI should optionally allow
   637	 * configuring host bridge windows using the _PRS and _SRS methods.
   638	 *
   639	 * But this is rarely implemented, so we manually enable a large 64bit BAR for
   640	 * PCIe device on AMD Family 15h (Models 30h-3fh) Processors here.
   641	 */
   642	static void pci_amd_enable_64bit_bar(struct pci_dev *dev)
   643	{
   644		struct resource *res, *conflict;
   645		u32 base, limit, high;
   646		unsigned i;
   647	
   648		for (i = 0; i < 8; ++i) {
   649			pci_read_config_dword(dev, AMD_141b_MMIO_BASE(i), &base);
   650			pci_read_config_dword(dev, AMD_141b_MMIO_HIGH(i), &high);
   651	
   652			/* Is this slot free? */
   653			if (!(base & (AMD_141b_MMIO_BASE_RE_MASK |
   654				      AMD_141b_MMIO_BASE_WE_MASK)))
   655				break;
   656	
   657			base >>= 8;
   658			base |= high << 24;
   659	
   660			/* Abort if a slot already configures a 64bit BAR. */
   661			if (base > 0x10000)
   662				return;
   663		}
   664		if (i == 8)
   665			return;
   666	
   667		res = kzalloc(sizeof(*res), GFP_KERNEL);
   668		if (!res)
   669			return;
   670	
   671		res->name = "PCI Bus 0000:00";
   672		res->flags = IORESOURCE_PREFETCH | IORESOURCE_MEM |
   673			IORESOURCE_MEM_64 | IORESOURCE_WINDOW;
 > 674		res->start = 0x100000000ull;
   675		res->end = 0xfd00000000ull - 1;
   676	
   677		/* Just grab the free area behind system memory for this */
   678		while ((conflict = request_resource_conflict(&iomem_resource, res)))
   679			res->start = conflict->end + 1;
   680	
   681		dev_info(&dev->dev, "adding root bus resource %pR\n", res);
   682	
   683		base = ((res->start >> 8) & AMD_141b_MMIO_BASE_MMIOBASE_MASK) |
   684			AMD_141b_MMIO_BASE_RE_MASK | AMD_141b_MMIO_BASE_WE_MASK;
   685		limit = ((res->end + 1) >> 8) & AMD_141b_MMIO_LIMIT_MMIOLIMIT_MASK;
 > 686		high = ((res->start >> 40) & AMD_141b_MMIO_HIGH_MMIOBASE_MASK) |

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
On Tue, Jul 11, 2017 at 3:07 PM, kbuild test robot <lkp@intel.com> wrote:

>         make ARCH=i386

Yeah, either this code shouldn't have been built on 32-bit arch at
all, or be portable.

>    arch/x86/pci/fixup.c: In function 'pci_amd_enable_64bit_bar':
>>> arch/x86/pci/fixup.c:674:15: warning: large integer implicitly truncated to unsigned type [-Woverflow]
>      res->start = 0x100000000ull;
>                   ^~~~~~~~~~~~~~
>    arch/x86/pci/fixup.c:675:13: warning: large integer implicitly truncated to unsigned type [-Woverflow]
>      res->end = 0xfd00000000ull - 1;
>                 ^~~~~~~~~~~~~~~
>>> arch/x86/pci/fixup.c:686:22: warning: right shift count >= width of type [-Wshift-count-overflow]

I suppose explicit casting will help.

>      high = ((res->start >> 40) & AMD_141b_MMIO_HIGH_MMIOBASE_MASK) |
>                          ^~
>    arch/x86/pci/fixup.c:687:21: warning: right shift count >= width of type [-Wshift-count-overflow]
>       ((((res->end + 1) >> 40) << AMD_141b_MMIO_HIGH_MMIOLIMIT_SHIFT)
>                         ^~

These can be done via upper_32_bits() + shift.