xref: /linux/include/acpi/pcc.h (revision 2c22dc1ee3a1d1c50bee5f0f71ebffa86c33e172)
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 
12 struct pcc_mbox_chan {
13 	struct mbox_chan *mchan;
14 	u64 shmem_base_addr;
15 	void __iomem *shmem;
16 	u64 shmem_size;
17 	u32 latency;
18 	u32 max_access_rate;
19 	u16 min_turnaround_time;
20 };
21 
22 /* Generic Communications Channel Shared Memory Region */
23 #define PCC_SIGNATURE			0x50434300
24 /* Generic Communications Channel Command Field */
25 #define PCC_CMD_GENERATE_DB_INTR	BIT(15)
26 /* Generic Communications Channel Status Field */
27 #define PCC_STATUS_CMD_COMPLETE		BIT(0)
28 #define PCC_STATUS_SCI_DOORBELL		BIT(1)
29 #define PCC_STATUS_ERROR		BIT(2)
30 #define PCC_STATUS_PLATFORM_NOTIFY	BIT(3)
31 /* Initiator Responder Communications Channel Flags */
32 #define PCC_CMD_COMPLETION_NOTIFY	BIT(0)
33 
34 #define MAX_PCC_SUBSPACES	256
35 #define PCC_ACK_FLAG_MASK	0x1
36 
37 #ifdef CONFIG_PCC
38 extern struct pcc_mbox_chan *
39 pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id);
40 extern void pcc_mbox_free_channel(struct pcc_mbox_chan *chan);
41 extern int pcc_mbox_ioremap(struct mbox_chan *chan);
42 #else
43 static inline struct pcc_mbox_chan *
pcc_mbox_request_channel(struct mbox_client * cl,int subspace_id)44 pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id)
45 {
46 	return ERR_PTR(-ENODEV);
47 }
pcc_mbox_free_channel(struct pcc_mbox_chan * chan)48 static inline void pcc_mbox_free_channel(struct pcc_mbox_chan *chan) { }
pcc_mbox_ioremap(struct mbox_chan * chan)49 static inline int pcc_mbox_ioremap(struct mbox_chan *chan)
50 {
51 	return 0;
52 };
53 #endif
54 
55 #endif /* _PCC_H */
56