Adds support for discovering Intel extended capability features from Vendor Specific Extended Capability (VSEC) registers in PCIe config space. Signed-off-by: David E. Box <david.e.box@xxxxxxxxxxxxxxx> --- V1: - Modified version of [1] applied to auxiliary bus driver. - Use bool instead of int to track whether any device has been added. [1] https://lore.kernel.org/all/20210922213007.2738388-4-david.e.box@xxxxxxxxxxxxxxx/ drivers/platform/x86/intel/extended_caps.c | 49 ++++++++++++++++++++++ 1 file changed, 49 insertions(+) diff --git a/drivers/platform/x86/intel/extended_caps.c b/drivers/platform/x86/intel/extended_caps.c index 03acea20b675..eca47d693b14 100644 --- a/drivers/platform/x86/intel/extended_caps.c +++ b/drivers/platform/x86/intel/extended_caps.c @@ -294,6 +294,54 @@ static bool extended_caps_walk_dvsec(struct pci_dev *pdev, unsigned long quirks) return have_devices; } +static bool extended_caps_walk_vsec(struct pci_dev *pdev, unsigned long quirks) +{ + bool have_devices = false; + int pos = 0; + + do { + struct extended_caps_header header; + u32 table, hdr; + int ret; + + pos = pci_find_next_ext_capability(pdev, pos, PCI_EXT_CAP_ID_VNDR); + if (!pos) + break; + + pci_read_config_dword(pdev, pos + PCI_VNDR_HEADER, &hdr); + + /* Support only revision 1 */ + header.rev = PCI_VNDR_HEADER_REV(hdr); + if (header.rev != 1) { + dev_warn(&pdev->dev, "Unsupported VSEC revision %d\n", + header.rev); + continue; + } + + header.id = PCI_VNDR_HEADER_ID(hdr); + header.length = PCI_VNDR_HEADER_LEN(hdr); + + /* entry, size, and table offset are the same as DVSEC */ + pci_read_config_byte(pdev, pos + INTEL_DVSEC_ENTRIES, + &header.num_entries); + pci_read_config_byte(pdev, pos + INTEL_DVSEC_SIZE, + &header.entry_size); + pci_read_config_dword(pdev, pos + INTEL_DVSEC_TABLE, + &table); + + header.tbir = INTEL_DVSEC_TABLE_BAR(table); + header.offset = INTEL_DVSEC_TABLE_OFFSET(table); + + ret = extended_caps_add_dev(pdev, &header, quirks); + if (ret) + continue; + + have_devices = true; + } while (true); + + return have_devices; +} + static int extended_caps_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) { struct extended_caps_platform_info *info; @@ -310,6 +358,7 @@ static int extended_caps_pci_probe(struct pci_dev *pdev, const struct pci_device quirks = info->quirks; have_devices |= extended_caps_walk_dvsec(pdev, quirks); + have_devices |= extended_caps_walk_vsec(pdev, quirks); if (info && (info->quirks & EXT_CAPS_QUIRK_NO_DVSEC)) have_devices |= extended_caps_walk_header(pdev, quirks, info->capabilities); -- 2.25.1
