1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * AMD Node helper functions and common defines
4 *
5 * Copyright (c) 2024, Advanced Micro Devices, Inc.
6 * All Rights Reserved.
7 *
8 * Author: Yazen Ghannam <Yazen.Ghannam@amd.com>
9 *
10 * Note:
11 * Items in this file may only be used in a single place.
12 * However, it's prudent to keep all AMD Node functionality
13 * in a unified place rather than spreading throughout the
14 * kernel.
15 */
16
17#ifndef _ASM_X86_AMD_NODE_H_
18#define _ASM_X86_AMD_NODE_H_
19
20#include <linux/pci.h>
21
22#define MAX_AMD_NUM_NODES 8
23#define AMD_NODE0_PCI_SLOT 0x18
24
25struct pci_dev *amd_node_get_func(u16 node, u8 func);
26struct pci_dev *amd_node_get_root(u16 node);
27
28static inline u16 amd_num_nodes(void)
29{
30 return topology_amd_nodes_per_pkg() * topology_max_packages();
31}
32
33#ifdef CONFIG_AMD_NODE
34int __must_check amd_smn_read(u16 node, u32 address, u32 *value);
35int __must_check amd_smn_write(u16 node, u32 address, u32 value);
36
37/* Should only be used by the HSMP driver. */
38int __must_check amd_smn_hsmp_rdwr(u16 node, u32 address, u32 *value, bool write);
39#else
40static inline int __must_check amd_smn_read(u16 node, u32 address, u32 *value) { return -ENODEV; }
41static inline int __must_check amd_smn_write(u16 node, u32 address, u32 value) { return -ENODEV; }
42
43static inline int __must_check amd_smn_hsmp_rdwr(u16 node, u32 address, u32 *value, bool write)
44{
45 return -ENODEV;
46}
47#endif /* CONFIG_AMD_NODE */
48
49/* helper for use with read_poll_timeout */
50static inline int smn_read_register(u32 reg)
51{
52 int data, rc;
53
54 rc = amd_smn_read(node: 0, address: reg, value: &data);
55 if (rc)
56 return rc;
57
58 return data;
59}
60#endif /*_ASM_X86_AMD_NODE_H_*/
61

source code of linux/arch/x86/include/asm/amd/node.h