1 /* 2 * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are met: 6 * 7 * Redistributions of source code must retain the above copyright notice, this 8 * list of conditions and the following disclaimer. 9 * 10 * Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 14 * Neither the name of ARM nor the names of its contributors may be used 15 * to endorse or promote products derived from this software without specific 16 * prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28 * POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <assert.h> 32 #include <debug.h> 33 #include <errno.h> 34 #include <runtime_svc.h> 35 #include <string.h> 36 37 /******************************************************************************* 38 * The 'rt_svc_descs' array holds the runtime service descriptors exported by 39 * services by placing them in the 'rt_svc_descs' linker section. 40 * The 'rt_svc_descs_indices' array holds the index of a descriptor in the 41 * 'rt_svc_descs' array. When an SMC arrives, the OEN[29:24] bits and the call 42 * type[31] bit in the function id are combined to get an index into the 43 * 'rt_svc_descs_indices' array. This gives the index of the descriptor in the 44 * 'rt_svc_descs' array which contains the SMC handler. 45 ******************************************************************************/ 46 #define RT_SVC_DESCS_START ((uintptr_t) (&__RT_SVC_DESCS_START__)) 47 #define RT_SVC_DESCS_END ((uintptr_t) (&__RT_SVC_DESCS_END__)) 48 uint8_t rt_svc_descs_indices[MAX_RT_SVCS]; 49 static rt_svc_desc_t *rt_svc_descs; 50 51 #define RT_SVC_DECS_NUM ((RT_SVC_DESCS_END - RT_SVC_DESCS_START)\ 52 / sizeof(rt_svc_desc_t)) 53 54 /******************************************************************************* 55 * Simple routine to sanity check a runtime service descriptor before using it 56 ******************************************************************************/ 57 static int32_t validate_rt_svc_desc(const rt_svc_desc_t *desc) 58 { 59 if (desc == NULL) 60 return -EINVAL; 61 62 if (desc->start_oen > desc->end_oen) 63 return -EINVAL; 64 65 if (desc->end_oen >= OEN_LIMIT) 66 return -EINVAL; 67 68 if (desc->call_type != SMC_TYPE_FAST && desc->call_type != SMC_TYPE_STD) 69 return -EINVAL; 70 71 /* A runtime service having no init or handle function doesn't make sense */ 72 if (desc->init == NULL && desc->handle == NULL) 73 return -EINVAL; 74 75 return 0; 76 } 77 78 /******************************************************************************* 79 * This function calls the initialisation routine in the descriptor exported by 80 * a runtime service. Once a descriptor has been validated, its start & end 81 * owning entity numbers and the call type are combined to form a unique oen. 82 * The unique oen is used as an index into the 'rt_svc_descs_indices' array. 83 * The index of the runtime service descriptor is stored at this index. 84 ******************************************************************************/ 85 void runtime_svc_init(void) 86 { 87 int rc = 0, index, start_idx, end_idx; 88 89 /* Assert the number of descriptors detected are less than maximum indices */ 90 assert((RT_SVC_DECS_NUM >= 0) && (RT_SVC_DECS_NUM < MAX_RT_SVCS)); 91 92 /* If no runtime services are implemented then simply bail out */ 93 if (RT_SVC_DECS_NUM == 0) 94 return; 95 96 /* Initialise internal variables to invalid state */ 97 memset(rt_svc_descs_indices, -1, sizeof(rt_svc_descs_indices)); 98 99 rt_svc_descs = (rt_svc_desc_t *) RT_SVC_DESCS_START; 100 for (index = 0; index < RT_SVC_DECS_NUM; index++) { 101 rt_svc_desc_t *service = &rt_svc_descs[index]; 102 103 /* 104 * An invalid descriptor is an error condition since it is 105 * difficult to predict the system behaviour in the absence 106 * of this service. 107 */ 108 rc = validate_rt_svc_desc(service); 109 if (rc) { 110 ERROR("Invalid runtime service descriptor %p\n", 111 (void *) service); 112 panic(); 113 } 114 115 /* 116 * The runtime service may have separate rt_svc_desc_t 117 * for its fast smc and standard smc. Since the service itself 118 * need to be initialized only once, only one of them will have 119 * an initialisation routine defined. Call the initialisation 120 * routine for this runtime service, if it is defined. 121 */ 122 if (service->init) { 123 rc = service->init(); 124 if (rc) { 125 ERROR("Error initializing runtime service %s\n", 126 service->name); 127 continue; 128 } 129 } 130 131 /* 132 * Fill the indices corresponding to the start and end 133 * owning entity numbers with the index of the 134 * descriptor which will handle the SMCs for this owning 135 * entity range. 136 */ 137 start_idx = get_unique_oen(rt_svc_descs[index].start_oen, 138 service->call_type); 139 assert(start_idx < MAX_RT_SVCS); 140 end_idx = get_unique_oen(rt_svc_descs[index].end_oen, 141 service->call_type); 142 assert(end_idx < MAX_RT_SVCS); 143 for (; start_idx <= end_idx; start_idx++) 144 rt_svc_descs_indices[start_idx] = index; 145 } 146 } 147