Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'pci-v4.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI fixes from Bjorn Helgaas:
"Fix AMD boot regression due to 64-bit window conflicting with system
memory (Christian König)"
* tag 'pci-v4.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
x86/PCI: Move and shrink AMD 64-bit window to avoid conflict
x86/PCI: Add "pci=big_root_window" option for AMD 64-bit windows
+30
-11
+6
Documentation/admin-guide/kernel-parameters.txt
+6
Documentation/admin-guide/kernel-parameters.txt
···
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3097
pcie_scan_all Scan all possible PCIe devices. Otherwise we
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only look for one device below a PCIe downstream
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port.
3100
+
big_root_window Try to add a big 64bit memory window to the PCIe
3101
+
root complex on AMD CPUs. Some GFX hardware
3102
+
can resize a BAR to allow access to all VRAM.
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+
Adding the window is slightly risky (it may
3104
+
conflict with unreported devices), so this
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+
taints the kernel.
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pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power
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Management.
+1
arch/x86/include/asm/pci_x86.h
+1
arch/x86/include/asm/pci_x86.h
+5
arch/x86/pci/common.c
+5
arch/x86/pci/common.c
···
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594
} else if (!strcmp(str, "nocrs")) {
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pci_probe |= PCI_ROOT_NO_CRS;
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return NULL;
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+
#ifdef CONFIG_PHYS_ADDR_T_64BIT
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+
} else if (!strcmp(str, "big_root_window")) {
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+
pci_probe |= PCI_BIG_ROOT_WINDOW;
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+
return NULL;
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+
#endif
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} else if (!strcmp(str, "earlydump")) {
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pci_early_dump_regs = 1;
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return NULL;
+18
-11
arch/x86/pci/fixup.c
+18
-11
arch/x86/pci/fixup.c
···
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662
*/
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663
static void pci_amd_enable_64bit_bar(struct pci_dev *dev)
664
664
{
665
-
unsigned i;
666
665
u32 base, limit, high;
667
-
struct resource *res, *conflict;
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struct pci_dev *other;
667
+
struct resource *res;
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+
unsigned i;
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+
int r;
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+
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+
if (!(pci_probe & PCI_BIG_ROOT_WINDOW))
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+
return;
669
673
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/* Check that we are the only device of that type */
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other = pci_get_device(dev->vendor, dev->device, NULL);
···
703
699
if (!res)
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return;
705
701
702
+
/*
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+
* Allocate a 256GB window directly below the 0xfd00000000 hardware
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+
* limit (see AMD Family 15h Models 30h-3Fh BKDG, sec 2.4.6).
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+
*/
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res->name = "PCI Bus 0000:00";
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res->flags = IORESOURCE_PREFETCH | IORESOURCE_MEM |
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IORESOURCE_MEM_64 | IORESOURCE_WINDOW;
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-
res->start = 0x100000000ull;
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+
res->start = 0xbd00000000ull;
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res->end = 0xfd00000000ull - 1;
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-
/* Just grab the free area behind system memory for this */
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-
while ((conflict = request_resource_conflict(&iomem_resource, res))) {
714
-
if (conflict->end >= res->end) {
715
-
kfree(res);
716
-
return;
717
-
}
718
-
res->start = conflict->end + 1;
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+
r = request_resource(&iomem_resource, res);
713
+
if (r) {
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+
kfree(res);
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+
return;
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}
720
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721
-
dev_info(&dev->dev, "adding root bus resource %pR\n", res);
718
+
dev_info(&dev->dev, "adding root bus resource %pR (tainting kernel)\n",
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+
res);
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+
add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
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723
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base = ((res->start >> 8) & AMD_141b_MMIO_BASE_MMIOBASE_MASK) |
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AMD_141b_MMIO_BASE_RE_MASK | AMD_141b_MMIO_BASE_WE_MASK;