xref: /openbmc/linux/include/linux/psp-tee.h (revision bade7e1f)
1 /* SPDX-License-Identifier: MIT */
2 /*
3  * AMD Trusted Execution Environment (TEE) interface
4  *
5  * Author: Rijo Thomas <Rijo-john.Thomas@amd.com>
6  *
7  * Copyright 2019 Advanced Micro Devices, Inc.
8  *
9  */
10 
11 #ifndef __PSP_TEE_H_
12 #define __PSP_TEE_H_
13 
14 #include <linux/types.h>
15 #include <linux/errno.h>
16 
17 /* This file defines the Trusted Execution Environment (TEE) interface commands
18  * and the API exported by AMD Secure Processor driver to communicate with
19  * AMD-TEE Trusted OS.
20  */
21 
22 /**
23  * enum tee_cmd_id - TEE Interface Command IDs
24  * @TEE_CMD_ID_LOAD_TA:          Load Trusted Application (TA) binary into
25  *                               TEE environment
26  * @TEE_CMD_ID_UNLOAD_TA:        Unload TA binary from TEE environment
27  * @TEE_CMD_ID_OPEN_SESSION:     Open session with loaded TA
28  * @TEE_CMD_ID_CLOSE_SESSION:    Close session with loaded TA
29  * @TEE_CMD_ID_INVOKE_CMD:       Invoke a command with loaded TA
30  * @TEE_CMD_ID_MAP_SHARED_MEM:   Map shared memory
31  * @TEE_CMD_ID_UNMAP_SHARED_MEM: Unmap shared memory
32  */
33 enum tee_cmd_id {
34 	TEE_CMD_ID_LOAD_TA = 1,
35 	TEE_CMD_ID_UNLOAD_TA,
36 	TEE_CMD_ID_OPEN_SESSION,
37 	TEE_CMD_ID_CLOSE_SESSION,
38 	TEE_CMD_ID_INVOKE_CMD,
39 	TEE_CMD_ID_MAP_SHARED_MEM,
40 	TEE_CMD_ID_UNMAP_SHARED_MEM,
41 };
42 
43 #ifdef CONFIG_CRYPTO_DEV_SP_PSP
44 /**
45  * psp_tee_process_cmd() - Process command in Trusted Execution Environment
46  * @cmd_id:     TEE command ID (&enum tee_cmd_id)
47  * @buf:        Command buffer for TEE processing. On success, is updated
48  *              with the response
49  * @len:        Length of command buffer in bytes
50  * @status:     On success, holds the TEE command execution status
51  *
52  * This function submits a command to the Trusted OS for processing in the
53  * TEE environment and waits for a response or until the command times out.
54  *
55  * Returns:
56  * 0 if TEE successfully processed the command
57  * -%ENODEV    if PSP device not available
58  * -%EINVAL    if invalid input
59  * -%ETIMEDOUT if TEE command timed out
60  * -%EBUSY     if PSP device is not responsive
61  */
62 int psp_tee_process_cmd(enum tee_cmd_id cmd_id, void *buf, size_t len,
63 			u32 *status);
64 
65 /**
66  * psp_check_tee_status() - Checks whether there is a TEE which a driver can
67  * talk to.
68  *
69  * This function can be used by AMD-TEE driver to query if there is TEE with
70  * which it can communicate.
71  *
72  * Returns:
73  * 0          if the device has TEE
74  * -%ENODEV   if there is no TEE available
75  */
76 int psp_check_tee_status(void);
77 
78 #else /* !CONFIG_CRYPTO_DEV_SP_PSP */
79 
psp_tee_process_cmd(enum tee_cmd_id cmd_id,void * buf,size_t len,u32 * status)80 static inline int psp_tee_process_cmd(enum tee_cmd_id cmd_id, void *buf,
81 				      size_t len, u32 *status)
82 {
83 	return -ENODEV;
84 }
85 
psp_check_tee_status(void)86 static inline int psp_check_tee_status(void)
87 {
88 	return -ENODEV;
89 }
90 #endif /* CONFIG_CRYPTO_DEV_SP_PSP */
91 #endif /* __PSP_TEE_H_ */
92