diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/pci/quirks.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index f681fb08f5e4..ed2ed867c34c 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -3423,6 +3423,61 @@ static int pci_quirk_amd_sb_acs(struct pci_dev *dev, u16 acs_flags) #endif } +/* + * Many Intel PCH root ports do provide ACS-like features to disable peer + * transactions and validate bus numbers in requests, but do not provide an + * actual PCIe ACS capability. This is the list of device IDs known to fall + * into that category as provided by Intel in Red Hat bugzilla 1037684. + */ +static const u16 pci_quirk_intel_pch_acs_ids[] = { + /* Ibexpeak PCH */ + 0x3b42, 0x3b43, 0x3b44, 0x3b45, 0x3b46, 0x3b47, 0x3b48, 0x3b49, + 0x3b4a, 0x3b4b, 0x3b4c, 0x3b4d, 0x3b4e, 0x3b4f, 0x3b50, 0x3b51, + /* Cougarpoint PCH */ + 0x1c10, 0x1c11, 0x1c12, 0x1c13, 0x1c14, 0x1c15, 0x1c16, 0x1c17, + 0x1c18, 0x1c19, 0x1c1a, 0x1c1b, 0x1c1c, 0x1c1d, 0x1c1e, 0x1c1f, + /* Pantherpoint PCH */ + 0x1e10, 0x1e11, 0x1e12, 0x1e13, 0x1e14, 0x1e15, 0x1e16, 0x1e17, + 0x1e18, 0x1e19, 0x1e1a, 0x1e1b, 0x1e1c, 0x1e1d, 0x1e1e, 0x1e1f, + /* Lynxpoint-H PCH */ + 0x8c10, 0x8c11, 0x8c12, 0x8c13, 0x8c14, 0x8c15, 0x8c16, 0x8c17, + 0x8c18, 0x8c19, 0x8c1a, 0x8c1b, 0x8c1c, 0x8c1d, 0x8c1e, 0x8c1f, + /* Lynxpoint-LP PCH */ + 0x9c10, 0x9c11, 0x9c12, 0x9c13, 0x9c14, 0x9c15, 0x9c16, 0x9c17, + 0x9c18, 0x9c19, 0x9c1a, 0x9c1b, + /* Wildcat PCH */ + 0x9c90, 0x9c91, 0x9c92, 0x9c93, 0x9c94, 0x9c95, 0x9c96, 0x9c97, + 0x9c98, 0x9c99, 0x9c9a, 0x9c9b, +}; + +static bool pci_quirk_intel_pch_acs_match(struct pci_dev *dev) +{ + int i; + + /* Filter out a few obvious non-matches first */ + if (!pci_is_pcie(dev) || pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) + return false; + + for (i = 0; i < ARRAY_SIZE(pci_quirk_intel_pch_acs_ids); i++) + if (pci_quirk_intel_pch_acs_ids[i] == dev->device) + return true; + + return false; +} + +#define INTEL_PCH_ACS_FLAGS (PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF | PCI_ACS_SV) + +static int pci_quirk_intel_pch_acs(struct pci_dev *dev, u16 acs_flags) +{ + u16 flags = dev->dev_flags & PCI_DEV_FLAGS_ACS_ENABLED_QUIRK ? + INTEL_PCH_ACS_FLAGS : 0; + + if (!pci_quirk_intel_pch_acs_match(dev)) + return -ENOTTY; + + return acs_flags & ~flags ? 0 : 1; +} + static const struct pci_dev_acs_enabled { u16 vendor; u16 device; @@ -3434,6 +3489,7 @@ static const struct pci_dev_acs_enabled { { PCI_VENDOR_ID_ATI, 0x439d, pci_quirk_amd_sb_acs }, { PCI_VENDOR_ID_ATI, 0x4384, pci_quirk_amd_sb_acs }, { PCI_VENDOR_ID_ATI, 0x4399, pci_quirk_amd_sb_acs }, + { PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_quirk_intel_pch_acs }, { 0 } }; @@ -3462,11 +3518,115 @@ int pci_dev_specific_acs_enabled(struct pci_dev *dev, u16 acs_flags) return -ENOTTY; } +/* Config space offset of Root Complex Base Address register */ +#define INTEL_LPC_RCBA_REG 0xf0 +/* 31:14 RCBA address */ +#define INTEL_LPC_RCBA_MASK 0xffffc000 +/* RCBA Enable */ +#define INTEL_LPC_RCBA_ENABLE (1 << 0) + +/* Backbone Scratch Pad Register */ +#define INTEL_BSPR_REG 0x1104 +/* Backbone Peer Non-Posted Disable */ +#define INTEL_BSPR_REG_BPNPD (1 << 8) +/* Backbone Peer Posted Disable */ +#define INTEL_BSPR_REG_BPPD (1 << 9) + +/* Upstream Peer Decode Configuration Register */ +#define INTEL_UPDCR_REG 0x1114 +/* 5:0 Peer Decode Enable bits */ +#define INTEL_UPDCR_REG_MASK 0x3f + +static int pci_quirk_enable_intel_lpc_acs(struct pci_dev *dev) +{ + u32 rcba, bspr, updcr; + void __iomem *rcba_mem; + + /* + * Read the RCBA register from the LPC (D31:F0). PCH root ports + * are D28:F* and therefore get probed before LPC, thus we can't + * use pci_get_slot/pci_read_config_dword here. + */ + pci_bus_read_config_dword(dev->bus, PCI_DEVFN(31, 0), + INTEL_LPC_RCBA_REG, &rcba); + if (!(rcba & INTEL_LPC_RCBA_ENABLE)) + return -EINVAL; + + rcba_mem = ioremap_nocache(rcba & INTEL_LPC_RCBA_MASK, + PAGE_ALIGN(INTEL_UPDCR_REG)); + if (!rcba_mem) + return -ENOMEM; + + /* + * The BSPR can disallow peer cycles, but it's set by soft strap and + * therefore read-only. If both posted and non-posted peer cycles are + * disallowed, we're ok. If either are allowed, then we need to use + * the UPDCR to disable peer decodes for each port. This provides the + * PCIe ACS equivalent of PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_UF + */ + bspr = readl(rcba_mem + INTEL_BSPR_REG); + bspr &= INTEL_BSPR_REG_BPNPD | INTEL_BSPR_REG_BPPD; + if (bspr != (INTEL_BSPR_REG_BPNPD | INTEL_BSPR_REG_BPPD)) { + updcr = readl(rcba_mem + INTEL_UPDCR_REG); + if (updcr & INTEL_UPDCR_REG_MASK) { + dev_info(&dev->dev, "Disabling UPDCR peer decodes\n"); + updcr &= ~INTEL_UPDCR_REG_MASK; + writel(updcr, rcba_mem + INTEL_UPDCR_REG); + } + } + + iounmap(rcba_mem); + return 0; +} + +/* Miscellaneous Port Configuration register */ +#define INTEL_MPC_REG 0xd8 +/* MPC: Invalid Receive Bus Number Check Enable */ +#define INTEL_MPC_REG_IRBNCE (1 << 26) + +static void pci_quirk_enable_intel_rp_mpc_acs(struct pci_dev *dev) +{ + u32 mpc; + + /* + * When enabled, the IRBNCE bit of the MPC register enables the + * equivalent of PCI ACS Source Validation (PCI_ACS_SV), which + * ensures that requester IDs fall within the bus number range + * of the bridge. Enable if not already. + */ + pci_read_config_dword(dev, INTEL_MPC_REG, &mpc); + if (!(mpc & INTEL_MPC_REG_IRBNCE)) { + dev_info(&dev->dev, "Enabling MPC IRBNCE\n"); + mpc |= INTEL_MPC_REG_IRBNCE; + pci_write_config_word(dev, INTEL_MPC_REG, mpc); + } +} + +static int pci_quirk_enable_intel_pch_acs(struct pci_dev *dev) +{ + if (!pci_quirk_intel_pch_acs_match(dev)) + return -ENOTTY; + + if (pci_quirk_enable_intel_lpc_acs(dev)) { + dev_warn(&dev->dev, "Failed to enable Intel PCH ACS quirk\n"); + return 0; + } + + pci_quirk_enable_intel_rp_mpc_acs(dev); + + dev->dev_flags |= PCI_DEV_FLAGS_ACS_ENABLED_QUIRK; + + dev_info(&dev->dev, "Intel 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 }, { 0 } }; |