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/linux/pci-tph.h | 21 +++++++++++++++++++++ include/linux/pci.h | 7 +++++++ 2 files changed, 28 insertions(+) create mode 100644 include/linux/pci-tph.h (limited to 'include/linux') diff --git a/include/linux/pci-tph.h b/include/linux/pci-tph.h new file mode 100644 index 000000000000..58654a334ffb --- /dev/null +++ b/include/linux/pci-tph.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * TPH (TLP Processing Hints) + * + * Copyright (C) 2024 Advanced Micro Devices, Inc. + * Eric Van Tassell + * Wei Huang + */ +#ifndef LINUX_PCI_TPH_H +#define LINUX_PCI_TPH_H + +#ifdef CONFIG_PCIE_TPH +void pcie_disable_tph(struct pci_dev *pdev); +int pcie_enable_tph(struct pci_dev *pdev, int mode); +#else +static inline void pcie_disable_tph(struct pci_dev *pdev) { } +static inline int pcie_enable_tph(struct pci_dev *pdev, int mode) +{ return -EINVAL; } +#endif + +#endif /* LINUX_PCI_TPH_H */ diff --git a/include/linux/pci.h b/include/linux/pci.h index 573b4c4c2be6..8351d76b6e12 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -434,6 +434,7 @@ struct pci_dev { unsigned int ats_enabled:1; /* Address Translation Svc */ 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 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 */ @@ -534,6 +535,12 @@ struct pci_dev { /* These methods index pci_reset_fn_methods[] */ u8 reset_methods[PCI_NUM_RESET_METHODS]; /* In priority order */ + +#ifdef CONFIG_PCIE_TPH + u16 tph_cap; /* TPH capability offset */ + u8 tph_mode; /* TPH mode */ + u8 tph_req_type; /* TPH requester type */ +#endif }; static inline struct pci_dev *pci_physfn(struct pci_dev *dev) -- cgit v1.2.3