LXR linux/drivers/crypto/ccp/tee-dev.h

   1/* SPDX-License-Identifier: MIT */
   2/*
   3 * Copyright (C) 2019,2021 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                 988
  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 */
  29enum 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 */
  41struct 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 */
  56struct 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
  64struct 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 */
  78enum tee_cmd_state {
  79        TEE_CMD_STATE_INIT,
  80        TEE_CMD_STATE_PROCESS,
  81        TEE_CMD_STATE_COMPLETED,
  82};
  83
  84/**
  85 * enum cmd_resp_state - TEE command's response status maintained by driver
  86 * @CMD_RESPONSE_INVALID:      initial state when no command is written to ring
  87 * @CMD_WAITING_FOR_RESPONSE:  driver waiting for response from TEE
  88 * @CMD_RESPONSE_TIMEDOUT:     failed to get response from TEE
  89 * @CMD_RESPONSE_COPIED:       driver has copied response from TEE
  90 */
  91enum cmd_resp_state {
  92        CMD_RESPONSE_INVALID,
  93        CMD_WAITING_FOR_RESPONSE,
  94        CMD_RESPONSE_TIMEDOUT,
  95        CMD_RESPONSE_COPIED,
  96};
  97
  98/**
  99 * struct tee_ring_cmd - Structure of the command buffer in TEE ring
 100 * @cmd_id:      refers to &enum tee_cmd_id. Command id for the ring buffer
 101 *               interface
 102 * @cmd_state:   refers to &enum tee_cmd_state
 103 * @status:      status of TEE command execution
 104 * @res0:        reserved region
 105 * @pdata:       private data (currently unused)
 106 * @res1:        reserved region
 107 * @buf:         TEE command specific buffer
 108 * @flag:        refers to &enum cmd_resp_state
 109 */
 110struct tee_ring_cmd {
 111        u32 cmd_id;
 112        u32 cmd_state;
 113        u32 status;
 114        u32 res0[1];
 115        u64 pdata;
 116        u32 res1[2];
 117        u8 buf[MAX_BUFFER_SIZE];
 118        u32 flag;
 119
 120        /* Total size: 1024 bytes */
 121} __packed;
 122
 123int tee_dev_init(struct psp_device *psp);
 124void tee_dev_destroy(struct psp_device *psp);
 125
 126#endif /* __TEE_DEV_H__ */
 127