intel_pmc_ipc.h

 1/* SPDX-License-Identifier: GPL-2.0 */
 2/*
 3 * Intel Core SoC Power Management Controller Header File
 4 *
 5 * Copyright (c) 2025, Intel Corporation.
 6 * All Rights Reserved.
 7 *
 8 */
 9#ifndef INTEL_PMC_IPC_H
10#define INTEL_PMC_IPC_H
11#include <linux/acpi.h>
12#include <linux/cleanup.h>
13
14#define IPC_SOC_REGISTER_ACCESS			0xAA
15#define IPC_SOC_SUB_CMD_READ			0x00
16#define IPC_SOC_SUB_CMD_WRITE			0x01
17#define PMC_IPCS_PARAM_COUNT			7
18#define VALID_IPC_RESPONSE			5
19
20struct pmc_ipc_cmd {
21	u32 cmd;
22	u32 sub_cmd;
23	u32 size;
24	u32 wbuf[4];
25};
26
27struct pmc_ipc_rbuf {
28	u32 buf[4];
29};
30
31/**
32 * intel_pmc_ipc() - PMC IPC Mailbox accessor
33 * @ipc_cmd:  Prepared input command to send
34 * @rbuf:     Allocated array for returned IPC data
35 *
36 * Return: 0 on success. Non-zero on mailbox error
37 */
38static inline int intel_pmc_ipc(struct pmc_ipc_cmd *ipc_cmd, struct pmc_ipc_rbuf *rbuf)
39{
40#ifdef CONFIG_ACPI
41	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
42	union acpi_object params[PMC_IPCS_PARAM_COUNT] = {
43		{.type = ACPI_TYPE_INTEGER,},
44		{.type = ACPI_TYPE_INTEGER,},
45		{.type = ACPI_TYPE_INTEGER,},
46		{.type = ACPI_TYPE_INTEGER,},
47		{.type = ACPI_TYPE_INTEGER,},
48		{.type = ACPI_TYPE_INTEGER,},
49		{.type = ACPI_TYPE_INTEGER,},
50	};
51	struct acpi_object_list arg_list = { PMC_IPCS_PARAM_COUNT, params };
52	int status;
53
54	if (!ipc_cmd || !rbuf)
55		return -EINVAL;
56
57	/*
58	 * 0: IPC Command
59	 * 1: IPC Sub Command
60	 * 2: Size
61	 * 3-6: Write Buffer for offset
62	 */
63	params[0].integer.value = ipc_cmd->cmd;
64	params[1].integer.value = ipc_cmd->sub_cmd;
65	params[2].integer.value = ipc_cmd->size;
66	params[3].integer.value = ipc_cmd->wbuf[0];
67	params[4].integer.value = ipc_cmd->wbuf[1];
68	params[5].integer.value = ipc_cmd->wbuf[2];
69	params[6].integer.value = ipc_cmd->wbuf[3];
70
71	status = acpi_evaluate_object(NULL, "\\IPCS", &arg_list, &buffer);
72	if (ACPI_FAILURE(status))
73		return -ENODEV;
74
75	union acpi_object *obj __free(kfree) = buffer.pointer;
76
77	if (obj && obj->type == ACPI_TYPE_PACKAGE &&
78	    obj->package.count == VALID_IPC_RESPONSE) {
79		const union acpi_object *objs = obj->package.elements;
80
81		if ((u8)objs[0].integer.value != 0)
82			return -EINVAL;
83
84		rbuf->buf[0] = objs[1].integer.value;
85		rbuf->buf[1] = objs[2].integer.value;
86		rbuf->buf[2] = objs[3].integer.value;
87		rbuf->buf[3] = objs[4].integer.value;
88	} else {
89		return -EINVAL;
90	}
91
92	return 0;
93#else
94	return -ENODEV;
95#endif /* CONFIG_ACPI */
96}
97
98#endif /* INTEL_PMC_IPC_H */