From f69767a1ada3ac74be2e1ac0795a05e1d1384eff Mon Sep 17 00:00:00 2001 From: Wei Huang Date: Wed, 2 Oct 2024 11:59:50 -0500 Subject: PCI: Add TLP Processing Hints (TPH) support Add support for PCIe TLP Processing Hints (TPH) support (see PCIe r6.2, sec 6.17). Add TPH register definitions in pci_regs.h, including the TPH Requester capability register, TPH Requester control register, TPH Completer capability, and the ST fields of MSI-X entry. Introduce pcie_enable_tph() and pcie_disable_tph(), enabling drivers to toggle TPH support and configure specific ST mode as needed. Also add a new kernel parameter, "pci=notph", allowing users to disable TPH support across the entire system. Link: https://lore.kernel.org/r/20241002165954.128085-2-wei.huang2@amd.com Co-developed-by: Jing Liu Co-developed-by: Paul Luse Co-developed-by: Eric Van Tassell Signed-off-by: Jing Liu Signed-off-by: Paul Luse Signed-off-by: Eric Van Tassell Signed-off-by: Wei Huang Signed-off-by: Bjorn Helgaas Reviewed-by: Ajit Khaparde Reviewed-by: Somnath Kotur Reviewed-by: Andy Gospodarek Reviewed-by: Jonathan Cameron Reviewed-by: Lukas Wunner --- include/uapi/linux/pci_regs.h | 37 +++++++++++++++++++++++++++++-------- 1 file changed, 29 insertions(+), 8 deletions(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h index 12323b3334a9..155dea741615 100644 --- a/include/uapi/linux/pci_regs.h +++ b/include/uapi/linux/pci_regs.h @@ -340,7 +340,8 @@ #define PCI_MSIX_ENTRY_UPPER_ADDR 0x4 /* Message Upper Address */ #define PCI_MSIX_ENTRY_DATA 0x8 /* Message Data */ #define PCI_MSIX_ENTRY_VECTOR_CTRL 0xc /* Vector Control */ -#define PCI_MSIX_ENTRY_CTRL_MASKBIT 0x00000001 +#define PCI_MSIX_ENTRY_CTRL_MASKBIT 0x00000001 /* Mask Bit */ +#define PCI_MSIX_ENTRY_CTRL_ST 0xffff0000 /* Steering Tag */ /* CompactPCI Hotswap Register */ @@ -659,6 +660,7 @@ #define PCI_EXP_DEVCAP2_ATOMIC_COMP64 0x00000100 /* 64b AtomicOp completion */ #define PCI_EXP_DEVCAP2_ATOMIC_COMP128 0x00000200 /* 128b AtomicOp completion */ #define PCI_EXP_DEVCAP2_LTR 0x00000800 /* Latency tolerance reporting */ +#define PCI_EXP_DEVCAP2_TPH_COMP_MASK 0x00003000 /* TPH completer support */ #define PCI_EXP_DEVCAP2_OBFF_MASK 0x000c0000 /* OBFF support mechanism */ #define PCI_EXP_DEVCAP2_OBFF_MSG 0x00040000 /* New message signaling */ #define PCI_EXP_DEVCAP2_OBFF_WAKE 0x00080000 /* Re-use WAKE# for OBFF */ @@ -1023,15 +1025,34 @@ #define PCI_DPA_CAP_SUBSTATE_MASK 0x1F /* # substates - 1 */ #define PCI_DPA_BASE_SIZEOF 16 /* size with 0 substates */ +/* TPH Completer Support */ +#define PCI_EXP_DEVCAP2_TPH_COMP_NONE 0x0 /* None */ +#define PCI_EXP_DEVCAP2_TPH_COMP_TPH_ONLY 0x1 /* TPH only */ +#define PCI_EXP_DEVCAP2_TPH_COMP_EXT_TPH 0x3 /* TPH and Extended TPH */ + /* TPH Requester */ #define PCI_TPH_CAP 4 /* capability register */ -#define PCI_TPH_CAP_LOC_MASK 0x600 /* location mask */ -#define PCI_TPH_LOC_NONE 0x000 /* no location */ -#define PCI_TPH_LOC_CAP 0x200 /* in capability */ -#define PCI_TPH_LOC_MSIX 0x400 /* in MSI-X */ -#define PCI_TPH_CAP_ST_MASK 0x07FF0000 /* ST table mask */ -#define PCI_TPH_CAP_ST_SHIFT 16 /* ST table shift */ -#define PCI_TPH_BASE_SIZEOF 0xc /* size with no ST table */ +#define PCI_TPH_CAP_ST_NS 0x00000001 /* No ST Mode Supported */ +#define PCI_TPH_CAP_ST_IV 0x00000002 /* Interrupt Vector Mode Supported */ +#define PCI_TPH_CAP_ST_DS 0x00000004 /* Device Specific Mode Supported */ +#define PCI_TPH_CAP_EXT_TPH 0x00000100 /* Ext TPH Requester Supported */ +#define PCI_TPH_CAP_LOC_MASK 0x00000600 /* ST Table Location */ +#define PCI_TPH_LOC_NONE 0x00000000 /* Not present */ +#define PCI_TPH_LOC_CAP 0x00000200 /* In capability */ +#define PCI_TPH_LOC_MSIX 0x00000400 /* In MSI-X */ +#define PCI_TPH_CAP_ST_MASK 0x07FF0000 /* ST Table Size */ +#define PCI_TPH_CAP_ST_SHIFT 16 /* ST Table Size shift */ +#define PCI_TPH_BASE_SIZEOF 0xc /* Size with no ST table */ + +#define PCI_TPH_CTRL 8 /* control register */ +#define PCI_TPH_CTRL_MODE_SEL_MASK 0x00000007 /* ST Mode Select */ +#define PCI_TPH_ST_NS_MODE 0x0 /* No ST Mode */ +#define PCI_TPH_ST_IV_MODE 0x1 /* Interrupt Vector Mode */ +#define PCI_TPH_ST_DS_MODE 0x2 /* Device Specific Mode */ +#define PCI_TPH_CTRL_REQ_EN_MASK 0x00000300 /* TPH Requester Enable */ +#define PCI_TPH_REQ_DISABLE 0x0 /* No TPH requests allowed */ +#define PCI_TPH_REQ_TPH_ONLY 0x1 /* TPH only requests allowed */ +#define PCI_TPH_REQ_EXT_TPH 0x3 /* Extended TPH requests allowed */ /* Downstream Port Containment */ #define PCI_EXP_DPC_CAP 0x04 /* DPC Capability */ -- cgit v1.2.3