xref: /openbmc/linux/drivers/tee/optee/optee_ffa.h (revision b7b3c35e)
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * Copyright (c) 2019-2021, Linaro Limited
4  */
5 
6 /*
7  * This file is exported by OP-TEE and is kept in sync between secure world
8  * and normal world drivers. We're using ARM FF-A 1.0 specification.
9  */
10 
11 #ifndef __OPTEE_FFA_H
12 #define __OPTEE_FFA_H
13 
14 #include <linux/arm_ffa.h>
15 
16 /*
17  * Normal world sends requests with FFA_MSG_SEND_DIRECT_REQ and
18  * responses are returned with FFA_MSG_SEND_DIRECT_RESP for normal
19  * messages.
20  *
21  * All requests with FFA_MSG_SEND_DIRECT_REQ and FFA_MSG_SEND_DIRECT_RESP
22  * are using the AArch32 SMC calling convention with register usage as
23  * defined in FF-A specification:
24  * w0:    Function ID (0x8400006F or 0x84000070)
25  * w1:    Source/Destination IDs
26  * w2:    Reserved (MBZ)
27  * w3-w7: Implementation defined, free to be used below
28  */
29 
30 #define OPTEE_FFA_VERSION_MAJOR	1
31 #define OPTEE_FFA_VERSION_MINOR	0
32 
33 #define OPTEE_FFA_BLOCKING_CALL(id)	(id)
34 #define OPTEE_FFA_YIELDING_CALL_BIT	31
35 #define OPTEE_FFA_YIELDING_CALL(id)	((id) | BIT(OPTEE_FFA_YIELDING_CALL_BIT))
36 
37 /*
38  * Returns the API version implemented, currently follows the FF-A version.
39  * Call register usage:
40  * w3:    Service ID, OPTEE_FFA_GET_API_VERSION
41  * w4-w7: Not used (MBZ)
42  *
43  * Return register usage:
44  * w3:    OPTEE_FFA_VERSION_MAJOR
45  * w4:    OPTEE_FFA_VERSION_MINOR
46  * w5-w7: Not used (MBZ)
47  */
48 #define OPTEE_FFA_GET_API_VERSION	OPTEE_FFA_BLOCKING_CALL(0)
49 
50 /*
51  * Returns the revision of OP-TEE.
52  *
53  * Used by non-secure world to figure out which version of the Trusted OS
54  * is installed. Note that the returned revision is the revision of the
55  * Trusted OS, not of the API.
56  *
57  * Call register usage:
58  * w3:    Service ID, OPTEE_FFA_GET_OS_VERSION
59  * w4-w7: Unused (MBZ)
60  *
61  * Return register usage:
62  * w3:    CFG_OPTEE_REVISION_MAJOR
63  * w4:    CFG_OPTEE_REVISION_MINOR
64  * w5:    TEE_IMPL_GIT_SHA1 (or zero if not supported)
65  */
66 #define OPTEE_FFA_GET_OS_VERSION	OPTEE_FFA_BLOCKING_CALL(1)
67 
68 /*
69  * Exchange capabilities between normal world and secure world.
70  *
71  * Currently there are no defined capabilities. When features are added new
72  * capabilities may be added.
73  *
74  * Call register usage:
75  * w3:    Service ID, OPTEE_FFA_EXCHANGE_CAPABILITIES
76  * w4-w7: Note used (MBZ)
77  *
78  * Return register usage:
79  * w3:    Error code, 0 on success
80  * w4:    Bit[7:0]:  Number of parameters needed for RPC to be supplied
81  *                   as the second MSG arg struct for
82  *                   OPTEE_FFA_YIELDING_CALL_WITH_ARG.
83  *        Bit[31:8]: Reserved (MBZ)
84  * w5-w7: Note used (MBZ)
85  */
86 #define OPTEE_FFA_EXCHANGE_CAPABILITIES OPTEE_FFA_BLOCKING_CALL(2)
87 
88 /*
89  * Unregister shared memory
90  *
91  * Call register usage:
92  * w3:    Service ID, OPTEE_FFA_YIELDING_CALL_UNREGISTER_SHM
93  * w4:    Shared memory handle, lower bits
94  * w5:    Shared memory handle, higher bits
95  * w6-w7: Not used (MBZ)
96  *
97  * Return register usage:
98  * w3:    Error code, 0 on success
99  * w4-w7: Note used (MBZ)
100  */
101 #define OPTEE_FFA_UNREGISTER_SHM	OPTEE_FFA_BLOCKING_CALL(3)
102 
103 /*
104  * Call with struct optee_msg_arg as argument in the supplied shared memory
105  * with a zero internal offset and normal cached memory attributes.
106  * Register usage:
107  * w3:    Service ID, OPTEE_FFA_YIELDING_CALL_WITH_ARG
108  * w4:    Lower 32 bits of a 64-bit Shared memory handle
109  * w5:    Upper 32 bits of a 64-bit Shared memory handle
110  * w6:    Offset into shared memory pointing to a struct optee_msg_arg
111  *	  right after the parameters of this struct (at offset
112  *	  OPTEE_MSG_GET_ARG_SIZE(num_params) follows a struct optee_msg_arg
113  *	  for RPC, this struct has reserved space for the number of RPC
114  *	  parameters as returned by OPTEE_FFA_EXCHANGE_CAPABILITIES.
115  * w7:    Not used (MBZ)
116  * Resume from RPC. Register usage:
117  * w3:    Service ID, OPTEE_FFA_YIELDING_CALL_RESUME
118  * w4-w6: Not used (MBZ)
119  * w7:    Resume info
120  *
121  * Normal return (yielding call is completed). Register usage:
122  * w3:    Error code, 0 on success
123  * w4:    OPTEE_FFA_YIELDING_CALL_RETURN_DONE
124  * w5-w7: Not used (MBZ)
125  *
126  * RPC interrupt return (RPC from secure world). Register usage:
127  * w3:    Error code == 0
128  * w4:    Any defined RPC code but OPTEE_FFA_YIELDING_CALL_RETURN_DONE
129  * w5-w6: Not used (MBZ)
130  * w7:    Resume info
131  *
132  * Possible error codes in register w3:
133  * 0:                       Success
134  * FFA_DENIED:              w4 isn't one of OPTEE_FFA_YIELDING_CALL_START
135  *                          OPTEE_FFA_YIELDING_CALL_RESUME
136  *
137  * Possible error codes for OPTEE_FFA_YIELDING_CALL_START,
138  * FFA_BUSY:               Number of OP-TEE OS threads exceeded,
139  *                         try again later
140  * FFA_DENIED:             RPC shared memory object not found
141  * FFA_INVALID_PARAMETER:  Bad shared memory handle or offset into the memory
142  *
143  * Possible error codes for OPTEE_FFA_YIELDING_CALL_RESUME
144  * FFA_INVALID_PARAMETER:  Bad resume info
145  */
146 #define OPTEE_FFA_YIELDING_CALL_WITH_ARG	OPTEE_FFA_YIELDING_CALL(0)
147 #define OPTEE_FFA_YIELDING_CALL_RESUME		OPTEE_FFA_YIELDING_CALL(1)
148 
149 #define OPTEE_FFA_YIELDING_CALL_RETURN_DONE		0
150 #define OPTEE_FFA_YIELDING_CALL_RETURN_RPC_CMD		1
151 #define OPTEE_FFA_YIELDING_CALL_RETURN_INTERRUPT	2
152 
153 #endif /*__OPTEE_FFA_H*/
154