include/acpi/pcc.h

   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 *
  44 pcc_mbox_request_channel(struct mbox_client *cl, int subspace_id)
  45 {
  46         return ERR_PTR(-ENODEV);
  47 }
  48 static inline void pcc_mbox_free_channel(struct pcc_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 */