diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 1f5c7898a246..ac47d6bc9946 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -3969,6 +3969,55 @@ static int pci_quirk_intel_pch_acs(struct pci_dev *dev, u16 acs_flags) return acs_flags & ~flags ? 0 : 1; } +/* + * Sunrise Point PCH root ports implement ACS, but unfortunately as shown in + * the datasheet (Intel 100 Series Chipset Family PCH Datasheet, Vol. 2, + * 12.1.46, 12.1.47)[1] this chipset uses dwords for the ACS capability and + * control registers whereas the PCIe spec packs them into words (Rev 3.0, + * 7.16 ACS Extended Capability). The bit definitions are correct, but the + * control register is at offset 8 instead of 6 and we should probably use + * dword accesses to them. This applies to the following PCI Device IDs, as + * found in volume 1 of the datasheet[2]: + * + * 0xa110-0xa11f Sunrise Point-H PCI Express Root Port #{0-16} + * 0xa167-0xa16a Sunrise Point-H PCI Express Root Port #{17-20} + * + * N.B. This doesn't fix what lspci shows. + * + * [1] http://www.intel.com/content/www/us/en/chipsets/100-series-chipset-datasheet-vol-2.html + * [2] http://www.intel.com/content/www/us/en/chipsets/100-series-chipset-datasheet-vol-1.html + */ +static bool pci_quirk_intel_spt_pch_acs_match(struct pci_dev *dev) +{ + return pci_is_pcie(dev) && + pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT && + ((dev->device & ~0xf) == 0xa110 || + (dev->device >= 0xa167 && dev->device <= 0xa16a)); +} + +#define INTEL_SPT_ACS_CTRL (PCI_ACS_CAP + 4) + +static int pci_quirk_intel_spt_pch_acs(struct pci_dev *dev, u16 acs_flags) +{ + int pos; + u32 cap, ctrl; + + if (!pci_quirk_intel_spt_pch_acs_match(dev)) + return -ENOTTY; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS); + if (!pos) + return -ENOTTY; + + /* see pci_acs_flags_enabled() */ + pci_read_config_dword(dev, pos + PCI_ACS_CAP, &cap); + acs_flags &= (cap | PCI_ACS_EC); + + pci_read_config_dword(dev, pos + INTEL_SPT_ACS_CTRL, &ctrl); + + return acs_flags & ~ctrl ? 0 : 1; +} + static int pci_quirk_mf_endpoint_acs(struct pci_dev *dev, u16 acs_flags) { /* @@ -4057,6 +4106,7 @@ static const struct pci_dev_acs_enabled { { PCI_VENDOR_ID_INTEL, 0x15b8, pci_quirk_mf_endpoint_acs }, /* Intel PCH root ports */ { PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_quirk_intel_pch_acs }, + { PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_quirk_intel_spt_pch_acs }, { 0x19a2, 0x710, pci_quirk_mf_endpoint_acs }, /* Emulex BE3-R */ { 0x10df, 0x720, pci_quirk_mf_endpoint_acs }, /* Emulex Skyhawk-R */ /* Cavium ThunderX */ @@ -4192,12 +4242,40 @@ static int pci_quirk_enable_intel_pch_acs(struct pci_dev *dev) return 0; } +static int pci_quirk_enable_intel_spt_pch_acs(struct pci_dev *dev) +{ + int pos; + u32 cap, ctrl; + + if (!pci_quirk_intel_spt_pch_acs_match(dev)) + return -ENOTTY; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS); + if (!pos) + return -ENOTTY; + + pci_read_config_dword(dev, pos + PCI_ACS_CAP, &cap); + pci_read_config_dword(dev, pos + INTEL_SPT_ACS_CTRL, &ctrl); + + ctrl |= (cap & PCI_ACS_SV); + ctrl |= (cap & PCI_ACS_RR); + ctrl |= (cap & PCI_ACS_CR); + ctrl |= (cap & PCI_ACS_UF); + + pci_write_config_dword(dev, pos + INTEL_SPT_ACS_CTRL, ctrl); + + dev_info(&dev->dev, "Intel SPT PCH root port ACS workaround enabled\n"); + + return 0; +} + static const struct pci_dev_enable_acs { u16 vendor; u16 device; int (*enable_acs)(struct pci_dev *dev); } pci_dev_enable_acs[] = { { PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_quirk_enable_intel_pch_acs }, + { PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_quirk_enable_intel_spt_pch_acs }, { 0 } };