1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * PCC (Platform Communications Channel) methods
4 */
5
6#ifndef _PCC_H
7#define _PCC_H
8
9#include <linux/mailbox_controller.h>
10#include <linux/mailbox_client.h>
11
12struct pcc_mbox_chan {
13 struct mbox_chan *mchan;
14 u64 shmem_base_addr;
15 u64 shmem_size;
16 u32 latency;
17 u32 max_access_rate;
18 u16 min_turnaround_time;
19};
20
21/* Generic Communications Channel Shared Memory Region */
22#define PCC_SIGNATURE 0x50434300
23/* Generic Communications Channel Command Field */
24#define PCC_CMD_GENERATE_DB_INTR BIT(15)
25/* Generic Communications Channel Status Field */
26#define PCC_STATUS_CMD_COMPLETE BIT(0)
27#define PCC_STATUS_SCI_DOORBELL BIT(1)
28#define PCC_STATUS_ERROR BIT(2)
29#define PCC_STATUS_PLATFORM_NOTIFY BIT(3)
30/* Initiator Responder Communications Channel Flags */
31#define PCC_CMD_COMPLETION_NOTIFY BIT(0)
32
33#define MAX_PCC_SUBSPACES 256
34
35#ifdef CONFIG_PCC
36extern struct pcc_mbox_chan *
37pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id);
38extern void pcc_mbox_free_channel(struct pcc_mbox_chan *chan);
39#else
40static inline struct pcc_mbox_chan *
41pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id)
42{
43 return ERR_PTR(-ENODEV);
44}
45static inline void pcc_mbox_free_channel(struct pcc_mbox_chan *chan) { }
46#endif
47
48#endif /* _PCC_H */
49

source code of linux/include/acpi/pcc.h