drivers/crypto/ccp/tee-dev.h

   1 /* SPDX-License-Identifier: MIT */
   2 /*
   3  * Copyright 2019 Advanced Micro Devices, Inc.
   4  *
   5  * Author: Rijo Thomas <Rijo-john.Thomas@amd.com>
   6  * Author: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
   7  *
   8  */
   9
  10 /* This file describes the TEE communication interface between host and AMD
  11  * Secure Processor
  12  */
  13
  14 #ifndef __TEE_DEV_H__
  15 #define __TEE_DEV_H__
  16
  17 #include <linux/device.h>
  18 #include <linux/mutex.h>
  19
  20 #define TEE_DEFAULT_TIMEOUT             10
  21 #define MAX_BUFFER_SIZE                 992
  22
  23 /**
  24  * enum tee_ring_cmd_id - TEE interface commands for ring buffer configuration
  25  * @TEE_RING_INIT_CMD:          Initialize ring buffer
  26  * @TEE_RING_DESTROY_CMD:       Destroy ring buffer
  27  * @TEE_RING_MAX_CMD:           Maximum command id
  28  */
  29 enum tee_ring_cmd_id {
  30         TEE_RING_INIT_CMD               = 0x00010000,
  31         TEE_RING_DESTROY_CMD            = 0x00020000,
  32         TEE_RING_MAX_CMD                = 0x000F0000,
  33 };
  34
  35 /**
  36  * struct tee_init_ring_cmd - Command to init TEE ring buffer
  37  * @low_addr:  bits [31:0] of the physical address of ring buffer
  38  * @hi_addr:   bits [63:32] of the physical address of ring buffer
  39  * @size:      size of ring buffer in bytes
  40  */
  41 struct tee_init_ring_cmd {
  42         u32 low_addr;
  43         u32 hi_addr;
  44         u32 size;
  45 };
  46
  47 #define MAX_RING_BUFFER_ENTRIES         32
  48
  49 /**
  50  * struct ring_buf_manager - Helper structure to manage ring buffer.
  51  * @ring_start:  starting address of ring buffer
  52  * @ring_size:   size of ring buffer in bytes
  53  * @ring_pa:     physical address of ring buffer
  54  * @wptr:        index to the last written entry in ring buffer
  55  */
  56 struct ring_buf_manager {
  57         struct mutex mutex;     /* synchronizes access to ring buffer */
  58         void *ring_start;
  59         u32 ring_size;
  60         phys_addr_t ring_pa;
  61         u32 wptr;
  62 };
  63
  64 struct psp_tee_device {
  65         struct device *dev;
  66         struct psp_device *psp;
  67         void __iomem *io_regs;
  68         struct tee_vdata *vdata;
  69         struct ring_buf_manager rb_mgr;
  70 };
  71
  72 /**
  73  * enum tee_cmd_state - TEE command states for the ring buffer interface
  74  * @TEE_CMD_STATE_INIT:      initial state of command when sent from host
  75  * @TEE_CMD_STATE_PROCESS:   command being processed by TEE environment
  76  * @TEE_CMD_STATE_COMPLETED: command processing completed
  77  */
  78 enum tee_cmd_state {
  79         TEE_CMD_STATE_INIT,
  80         TEE_CMD_STATE_PROCESS,
  81         TEE_CMD_STATE_COMPLETED,
  82 };
  83
  84 /**
  85  * struct tee_ring_cmd - Structure of the command buffer in TEE ring
  86  * @cmd_id:      refers to &enum tee_cmd_id. Command id for the ring buffer
  87  *               interface
  88  * @cmd_state:   refers to &enum tee_cmd_state
  89  * @status:      status of TEE command execution
  90  * @res0:        reserved region
  91  * @pdata:       private data (currently unused)
  92  * @res1:        reserved region
  93  * @buf:         TEE command specific buffer
  94  */
  95 struct tee_ring_cmd {
  96         u32 cmd_id;
  97         u32 cmd_state;
  98         u32 status;
  99         u32 res0[1];
 100         u64 pdata;
 101         u32 res1[2];
 102         u8 buf[MAX_BUFFER_SIZE];
 103
 104         /* Total size: 1024 bytes */
 105 } __packed;
 106
 107 int tee_dev_init(struct psp_device *psp);
 108 void tee_dev_destroy(struct psp_device *psp);
 109
 110 #endif /* __TEE_DEV_H__ */