1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * TPH (TLP Processing Hints)
4 *
5 * Copyright (C) 2024 Advanced Micro Devices, Inc.
6 * Eric Van Tassell <Eric.VanTassell@amd.com>
7 * Wei Huang <wei.huang2@amd.com>
8 */
9#ifndef LINUX_PCI_TPH_H
10#define LINUX_PCI_TPH_H
11
12/*
13 * According to the ECN for PCI Firmware Spec, Steering Tag can be different
14 * depending on the memory type: Volatile Memory or Persistent Memory. When a
15 * caller query about a target's Steering Tag, it must provide the target's
16 * tph_mem_type. ECN link: https://members.pcisig.com/wg/PCI-SIG/document/15470.
17 */
18enum tph_mem_type {
19 TPH_MEM_TYPE_VM, /* volatile memory */
20 TPH_MEM_TYPE_PM /* persistent memory */
21};
22
23#ifdef CONFIG_PCIE_TPH
24int pcie_tph_set_st_entry(struct pci_dev *pdev,
25 unsigned int index, u16 tag);
26int pcie_tph_get_cpu_st(struct pci_dev *dev,
27 enum tph_mem_type mem_type,
28 unsigned int cpu_uid, u16 *tag);
29void pcie_disable_tph(struct pci_dev *pdev);
30int pcie_enable_tph(struct pci_dev *pdev, int mode);
31u16 pcie_tph_get_st_table_size(struct pci_dev *pdev);
32#else
33static inline int pcie_tph_set_st_entry(struct pci_dev *pdev,
34 unsigned int index, u16 tag)
35{ return -EINVAL; }
36static inline int pcie_tph_get_cpu_st(struct pci_dev *dev,
37 enum tph_mem_type mem_type,
38 unsigned int cpu_uid, u16 *tag)
39{ return -EINVAL; }
40static inline void pcie_disable_tph(struct pci_dev *pdev) { }
41static inline int pcie_enable_tph(struct pci_dev *pdev, int mode)
42{ return -EINVAL; }
43#endif
44
45#endif /* LINUX_PCI_TPH_H */
46