1 /*
2 * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #ifndef RUNTIME_SVC_H
8 #define RUNTIME_SVC_H
9
10 #include <common/bl_common.h> /* to include exception types */
11 #include <lib/cassert.h>
12 #include <lib/utils_def.h>
13 #include <smccc_helpers.h> /* to include SMCCC definitions */
14
15 /*******************************************************************************
16 * Structure definition, typedefs & constants for the runtime service framework
17 ******************************************************************************/
18
19 /*
20 * Constants to allow the assembler access a runtime service
21 * descriptor
22 */
23 #ifdef __aarch64__
24 #define RT_SVC_SIZE_LOG2 U(5)
25 #define RT_SVC_DESC_INIT U(16)
26 #define RT_SVC_DESC_HANDLE U(24)
27 #else
28 #define RT_SVC_SIZE_LOG2 U(4)
29 #define RT_SVC_DESC_INIT U(8)
30 #define RT_SVC_DESC_HANDLE U(12)
31 #endif /* __aarch64__ */
32 #define SIZEOF_RT_SVC_DESC (U(1) << RT_SVC_SIZE_LOG2)
33
34
35 /*
36 * In SMCCC 1.X, the function identifier has 6 bits for the owning entity number
37 * and a single bit for the type of smc call. When taken together, those values
38 * limit the maximum number of runtime services to 128.
39 */
40 #define MAX_RT_SVCS U(128)
41
42 #ifndef __ASSEMBLER__
43
44 /* Prototype for runtime service initializing function */
45 typedef int32_t (*rt_svc_init_t)(void);
46
47 /*
48 * Prototype for runtime service SMC handler function. x0 (SMC Function ID) to
49 * x4 are as passed by the caller. Rest of the arguments to SMC and the context
50 * can be accessed using the handle pointer. The cookie parameter is reserved
51 * for future use
52 */
53 typedef uintptr_t (*rt_svc_handle_t)(uint32_t smc_fid,
54 u_register_t x1,
55 u_register_t x2,
56 u_register_t x3,
57 u_register_t x4,
58 void *cookie,
59 void *handle,
60 u_register_t flags);
61 typedef struct rt_svc_desc {
62 uint8_t start_oen;
63 uint8_t end_oen;
64 uint8_t call_type;
65 const char *name;
66 rt_svc_init_t init;
67 rt_svc_handle_t handle;
68 } rt_svc_desc_t;
69
70 /*
71 * Convenience macros to declare a service descriptor
72 */
73 #define DECLARE_RT_SVC(_name, _start, _end, _type, _setup, _smch) \
74 static const rt_svc_desc_t __svc_desc_ ## _name \
75 __section("rt_svc_descs") __used = { \
76 .start_oen = (_start), \
77 .end_oen = (_end), \
78 .call_type = (_type), \
79 .name = #_name, \
80 .init = (_setup), \
81 .handle = (_smch) \
82 }
83
84 /*
85 * Compile time assertions related to the 'rt_svc_desc' structure to:
86 * 1. ensure that the assembler and the compiler view of the size
87 * of the structure are the same.
88 * 2. ensure that the assembler and the compiler see the initialisation
89 * routine at the same offset.
90 * 3. ensure that the assembler and the compiler see the handler
91 * routine at the same offset.
92 */
93 CASSERT((sizeof(rt_svc_desc_t) == SIZEOF_RT_SVC_DESC), \
94 assert_sizeof_rt_svc_desc_mismatch);
95 CASSERT(RT_SVC_DESC_INIT == __builtin_offsetof(rt_svc_desc_t, init), \
96 assert_rt_svc_desc_init_offset_mismatch);
97 CASSERT(RT_SVC_DESC_HANDLE == __builtin_offsetof(rt_svc_desc_t, handle), \
98 assert_rt_svc_desc_handle_offset_mismatch);
99
100
101 /*
102 * This function combines the call type and the owning entity number
103 * corresponding to a runtime service to generate a unique owning entity number.
104 * This unique oen is used to access an entry in the 'rt_svc_descs_indices'
105 * array. The entry contains the index of the service descriptor in the
106 * 'rt_svc_descs' array.
107 */
get_unique_oen(uint32_t oen,uint32_t call_type)108 static inline uint32_t get_unique_oen(uint32_t oen, uint32_t call_type)
109 {
110 return ((call_type & FUNCID_TYPE_MASK) << FUNCID_OEN_WIDTH) |
111 (oen & FUNCID_OEN_MASK);
112 }
113
114 /*
115 * This function generates the unique owning entity number from the SMC Function
116 * ID. This unique oen is used to access an entry in the 'rt_svc_descs_indices'
117 * array to invoke the corresponding runtime service handler during SMC
118 * handling.
119 */
get_unique_oen_from_smc_fid(uint32_t fid)120 static inline uint32_t get_unique_oen_from_smc_fid(uint32_t fid)
121 {
122 return get_unique_oen(GET_SMC_OEN(fid), GET_SMC_TYPE(fid));
123 }
124
125 /*******************************************************************************
126 * Function & variable prototypes
127 ******************************************************************************/
128 void runtime_svc_init(void);
129 uintptr_t handle_runtime_svc(uint32_t smc_fid, void *cookie, void *handle,
130 unsigned int flags);
131 IMPORT_SYM(uintptr_t, __RT_SVC_DESCS_START__, RT_SVC_DESCS_START);
132 IMPORT_SYM(uintptr_t, __RT_SVC_DESCS_END__, RT_SVC_DESCS_END);
133 void init_crash_reporting(void);
134
135 extern uint8_t rt_svc_descs_indices[MAX_RT_SVCS];
136
137 #endif /*__ASSEMBLER__*/
138 #endif /* RUNTIME_SVC_H */
139