From: Dan Williams Date: Fri, 31 Oct 2025 21:28:57 +0000 (-0700) Subject: PCI: Add PCIe Device 3 Extended Capability enumeration X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c0c1262fbfbafe943dbccd5f97b500b72dbd2205;p=thirdparty%2Fkernel%2Flinux.git PCI: Add PCIe Device 3 Extended Capability enumeration PCIe r7.0 Section 7.7.9 Device 3 Extended Capability Structure, defines the canonical location for determining the Flit Mode of a device. This status is a dependency for PCIe IDE enabling. Add a new fm_enabled flag to 'struct pci_dev'. Cc: Lukas Wunner Cc: Ilpo Järvinen Cc: Bjorn Helgaas Cc: Samuel Ortiz Cc: Alexey Kardashevskiy Cc: Xu Yilun Acked-by: Bjorn Helgaas Reviewed-by: Jonathan Cameron Link: https://patch.msgid.link/20251031212902.2256310-6-dan.j.williams@intel.com Signed-off-by: Dan Williams --- diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index d1467348c1699..3b54f1720be57 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2283,6 +2283,17 @@ int pci_configure_extended_tags(struct pci_dev *dev, void *ign) return 0; } +static void pci_dev3_init(struct pci_dev *pdev) +{ + u16 cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_DEV3); + u32 val = 0; + + if (!cap) + return; + pci_read_config_dword(pdev, cap + PCI_DEV3_STA, &val); + pdev->fm_enabled = !!(val & PCI_DEV3_STA_SEGMENT); +} + /** * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable * @dev: PCI device to query @@ -2667,6 +2678,7 @@ static void pci_init_capabilities(struct pci_dev *dev) pci_doe_init(dev); /* Data Object Exchange */ pci_tph_init(dev); /* TLP Processing Hints */ pci_rebar_init(dev); /* Resizable BAR */ + pci_dev3_init(dev); /* Device 3 capabilities */ pci_ide_init(dev); /* Link Integrity and Data Encryption */ pcie_report_downtraining(dev); diff --git a/include/linux/pci.h b/include/linux/pci.h index 2f9c0cb6a50a0..ea94799c81b0d 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -450,6 +450,7 @@ struct pci_dev { unsigned int pasid_enabled:1; /* Process Address Space ID */ unsigned int pri_enabled:1; /* Page Request Interface */ unsigned int tph_enabled:1; /* TLP Processing Hints */ + unsigned int fm_enabled:1; /* Flit Mode (segment captured) */ unsigned int is_managed:1; /* Managed via devres */ unsigned int is_msi_managed:1; /* MSI release via devres installed */ unsigned int needs_freset:1; /* Requires fundamental reset */ diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h index f2759c1097bce..3add74ae25948 100644 --- a/include/uapi/linux/pci_regs.h +++ b/include/uapi/linux/pci_regs.h @@ -755,6 +755,7 @@ #define PCI_EXT_CAP_ID_NPEM 0x29 /* Native PCIe Enclosure Management */ #define PCI_EXT_CAP_ID_PL_32GT 0x2A /* Physical Layer 32.0 GT/s */ #define PCI_EXT_CAP_ID_DOE 0x2E /* Data Object Exchange */ +#define PCI_EXT_CAP_ID_DEV3 0x2F /* Device 3 Capability/Control/Status */ #define PCI_EXT_CAP_ID_IDE 0x30 /* Integrity and Data Encryption */ #define PCI_EXT_CAP_ID_PL_64GT 0x31 /* Physical Layer 64.0 GT/s */ #define PCI_EXT_CAP_ID_MAX PCI_EXT_CAP_ID_PL_64GT @@ -1246,6 +1247,12 @@ /* Deprecated old name, replaced with PCI_DOE_DATA_OBJECT_DISC_RSP_3_TYPE */ #define PCI_DOE_DATA_OBJECT_DISC_RSP_3_PROTOCOL PCI_DOE_DATA_OBJECT_DISC_RSP_3_TYPE +/* Device 3 Extended Capability */ +#define PCI_DEV3_CAP 0x04 /* Device 3 Capabilities Register */ +#define PCI_DEV3_CTL 0x08 /* Device 3 Control Register */ +#define PCI_DEV3_STA 0x0c /* Device 3 Status Register */ +#define PCI_DEV3_STA_SEGMENT 0x8 /* Segment Captured (end-to-end flit-mode detected) */ + /* Compute Express Link (CXL r3.1, sec 8.1.5) */ #define PCI_DVSEC_CXL_PORT 3 #define PCI_DVSEC_CXL_PORT_CTL 0x0c