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 */ 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 * 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 */ 91 enum 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 */ 110 struct 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; 122 123 int tee_dev_init(struct psp_device *psp); 124 void tee_dev_destroy(struct psp_device *psp); 125 126 #endif /* __TEE_DEV_H__ */ 127