1 /* 2 * Copyright (c) 2013-2014, 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 32 /******************************************************************************* 33 * This is the Secure Payload Dispatcher (SPD). The dispatcher is meant to be a 34 * plug-in component to the Secure Monitor, registered as a runtime service. The 35 * SPD is expected to be a functional extension of the Secure Payload (SP) that 36 * executes in Secure EL1. The Secure Monitor will delegate all SMCs targeting 37 * the Trusted OS/Applications range to the dispatcher. The SPD will either 38 * handle the request locally or delegate it to the Secure Payload. It is also 39 * responsible for initialising and maintaining communication with the SP. 40 ******************************************************************************/ 41 #include <stdio.h> 42 #include <string.h> 43 #include <assert.h> 44 #include <arch_helpers.h> 45 #include <console.h> 46 #include <platform.h> 47 #include <context_mgmt.h> 48 #include <runtime_svc.h> 49 #include <bl31.h> 50 #include <tsp.h> 51 #include <psci.h> 52 #include <tspd_private.h> 53 #include <debug.h> 54 #include <uuid.h> 55 56 /******************************************************************************* 57 * Single structure to hold information about the various entry points into the 58 * Secure Payload. It is initialised once on the primary core after a cold boot. 59 ******************************************************************************/ 60 entry_info *tsp_entry_info; 61 62 /******************************************************************************* 63 * Array to keep track of per-cpu Secure Payload state 64 ******************************************************************************/ 65 tsp_context tspd_sp_context[TSPD_CORE_COUNT]; 66 67 68 /* TSP UID */ 69 DEFINE_SVC_UUID(tsp_uuid, 70 0x5b3056a0, 0x3291, 0x427b, 0x98, 0x11, 71 0x71, 0x68, 0xca, 0x50, 0xf3, 0xfa); 72 73 int32_t tspd_init(meminfo *bl32_meminfo); 74 75 76 /******************************************************************************* 77 * Secure Payload Dispatcher setup. The SPD finds out the SP entrypoint and type 78 * (aarch32/aarch64) if not already known and initialises the context for entry 79 * into the SP for its initialisation. 80 ******************************************************************************/ 81 int32_t tspd_setup(void) 82 { 83 el_change_info *image_info; 84 int32_t rc; 85 uint64_t mpidr = read_mpidr(); 86 uint32_t linear_id; 87 88 linear_id = platform_get_core_pos(mpidr); 89 90 /* 91 * Get information about the Secure Payload (BL32) image. Its 92 * absence is a critical failure. TODO: Add support to 93 * conditionally include the SPD service 94 */ 95 image_info = bl31_get_next_image_info(SECURE); 96 assert(image_info); 97 98 /* 99 * If there's no valid entry point for SP, we return a non-zero value 100 * signalling failure initializing the service. We bail out without 101 * registering any handlers 102 */ 103 if (!image_info->entrypoint) 104 return 1; 105 106 /* 107 * We could inspect the SP image and determine it's execution 108 * state i.e whether AArch32 or AArch64. Assuming it's AArch64 109 * for the time being. 110 */ 111 rc = tspd_init_secure_context(image_info->entrypoint, 112 TSP_AARCH64, 113 mpidr, 114 &tspd_sp_context[linear_id]); 115 assert(rc == 0); 116 117 /* 118 * All TSPD initialization done. Now register our init function with 119 * BL31 for deferred invocation 120 */ 121 bl31_register_bl32_init(&tspd_init); 122 123 return rc; 124 } 125 126 /******************************************************************************* 127 * This function passes control to the Secure Payload image (BL32) for the first 128 * time on the primary cpu after a cold boot. It assumes that a valid secure 129 * context has already been created by tspd_setup() which can be directly used. 130 * It also assumes that a valid non-secure context has been initialised by PSCI 131 * so it does not need to save and restore any non-secure state. This function 132 * performs a synchronous entry into the Secure payload. The SP passes control 133 * back to this routine through a SMC. It also passes the extents of memory made 134 * available to BL32 by BL31. 135 ******************************************************************************/ 136 int32_t tspd_init(meminfo *bl32_meminfo) 137 { 138 uint64_t mpidr = read_mpidr(); 139 uint32_t linear_id = platform_get_core_pos(mpidr); 140 uint64_t rc; 141 tsp_context *tsp_ctx = &tspd_sp_context[linear_id]; 142 143 /* 144 * Arrange for passing a pointer to the meminfo structure 145 * describing the memory extents available to the secure 146 * payload. 147 * TODO: We are passing a pointer to BL31 internal memory 148 * whereas this structure should be copied to a communication 149 * buffer between the SP and SPD. 150 */ 151 write_ctx_reg(get_gpregs_ctx(&tsp_ctx->cpu_ctx), 152 CTX_GPREG_X0, 153 (uint64_t) bl32_meminfo); 154 155 /* 156 * Arrange for an entry into the test secure payload. We expect an array 157 * of vectors in return 158 */ 159 rc = tspd_synchronous_sp_entry(tsp_ctx); 160 assert(rc != 0); 161 if (rc) { 162 tsp_ctx->state = TSP_STATE_ON; 163 164 /* 165 * TSP has been successfully initialized. Register power 166 * managemnt hooks with PSCI 167 */ 168 psci_register_spd_pm_hook(&tspd_pm); 169 } 170 171 return rc; 172 } 173 174 175 /******************************************************************************* 176 * This function is responsible for handling all SMCs in the Trusted OS/App 177 * range from the non-secure state as defined in the SMC Calling Convention 178 * Document. It is also responsible for communicating with the Secure payload 179 * to delegate work and return results back to the non-secure state. Lastly it 180 * will also return any information that the secure payload needs to do the 181 * work assigned to it. 182 ******************************************************************************/ 183 uint64_t tspd_smc_handler(uint32_t smc_fid, 184 uint64_t x1, 185 uint64_t x2, 186 uint64_t x3, 187 uint64_t x4, 188 void *cookie, 189 void *handle, 190 uint64_t flags) 191 { 192 cpu_context *ns_cpu_context; 193 gp_regs *ns_gp_regs; 194 unsigned long mpidr = read_mpidr(); 195 uint32_t linear_id = platform_get_core_pos(mpidr), ns; 196 tsp_context *tsp_ctx = &tspd_sp_context[linear_id]; 197 198 /* Determine which security state this SMC originated from */ 199 ns = is_caller_non_secure(flags); 200 201 switch (smc_fid) { 202 203 /* 204 * This function ID is used only by the SP to indicate it has 205 * finished initialising itself after a cold boot 206 */ 207 case TSP_ENTRY_DONE: 208 if (ns) 209 SMC_RET1(handle, SMC_UNK); 210 211 /* 212 * Stash the SP entry points information. This is done 213 * only once on the primary cpu 214 */ 215 assert(tsp_entry_info == NULL); 216 tsp_entry_info = (entry_info *) x1; 217 218 /* 219 * SP reports completion. The SPD must have initiated 220 * the original request through a synchronous entry 221 * into the SP. Jump back to the original C runtime 222 * context. 223 */ 224 tspd_synchronous_sp_exit(tsp_ctx, x1); 225 226 /* Should never reach here */ 227 assert(0); 228 229 /* 230 * These function IDs is used only by the SP to indicate it has 231 * finished: 232 * 1. turning itself on in response to an earlier psci 233 * cpu_on request 234 * 2. resuming itself after an earlier psci cpu_suspend 235 * request. 236 */ 237 case TSP_ON_DONE: 238 case TSP_RESUME_DONE: 239 240 /* 241 * These function IDs is used only by the SP to indicate it has 242 * finished: 243 * 1. suspending itself after an earlier psci cpu_suspend 244 * request. 245 * 2. turning itself off in response to an earlier psci 246 * cpu_off request. 247 */ 248 case TSP_OFF_DONE: 249 case TSP_SUSPEND_DONE: 250 if (ns) 251 SMC_RET1(handle, SMC_UNK); 252 253 /* 254 * SP reports completion. The SPD must have initiated the 255 * original request through a synchronous entry into the SP. 256 * Jump back to the original C runtime context, and pass x1 as 257 * return value to the caller 258 */ 259 tspd_synchronous_sp_exit(tsp_ctx, x1); 260 261 /* Should never reach here */ 262 assert(0); 263 264 /* 265 * Request from non-secure client to perform an 266 * arithmetic operation or response from secure 267 * payload to an earlier request. 268 */ 269 case TSP_FID_ADD: 270 case TSP_FID_SUB: 271 case TSP_FID_MUL: 272 case TSP_FID_DIV: 273 if (ns) { 274 /* 275 * This is a fresh request from the non-secure client. 276 * The parameters are in x1 and x2. Figure out which 277 * registers need to be preserved, save the non-secure 278 * state and send the request to the secure payload. 279 */ 280 assert(handle == cm_get_context(mpidr, NON_SECURE)); 281 cm_el1_sysregs_context_save(NON_SECURE); 282 283 /* Save x1 and x2 for use by TSP_GET_ARGS call below */ 284 SMC_SET_GP(handle, CTX_GPREG_X1, x1); 285 SMC_SET_GP(handle, CTX_GPREG_X2, x2); 286 287 /* 288 * We are done stashing the non-secure context. Ask the 289 * secure payload to do the work now. 290 */ 291 292 /* 293 * Verify if there is a valid context to use, copy the 294 * operation type and parameters to the secure context 295 * and jump to the fast smc entry point in the secure 296 * payload. Entry into S-EL1 will take place upon exit 297 * from this function. 298 */ 299 assert(&tsp_ctx->cpu_ctx == cm_get_context(mpidr, SECURE)); 300 set_aapcs_args7(&tsp_ctx->cpu_ctx, smc_fid, x1, x2, 0, 0, 301 0, 0, 0); 302 cm_set_el3_elr(SECURE, (uint64_t) tsp_entry_info->fast_smc_entry); 303 cm_el1_sysregs_context_restore(SECURE); 304 cm_set_next_eret_context(SECURE); 305 306 return smc_fid; 307 } else { 308 /* 309 * This is the result from the secure client of an 310 * earlier request. The results are in x1-x2. Copy it 311 * into the non-secure context, save the secure state 312 * and return to the non-secure state. 313 */ 314 assert(handle == cm_get_context(mpidr, SECURE)); 315 cm_el1_sysregs_context_save(SECURE); 316 317 /* Get a reference to the non-secure context */ 318 ns_cpu_context = cm_get_context(mpidr, NON_SECURE); 319 assert(ns_cpu_context); 320 ns_gp_regs = get_gpregs_ctx(ns_cpu_context); 321 322 /* Restore non-secure state */ 323 cm_el1_sysregs_context_restore(NON_SECURE); 324 cm_set_next_eret_context(NON_SECURE); 325 326 SMC_RET2(ns_gp_regs, x1, x2); 327 } 328 329 break; 330 331 /* 332 * This is a request from the secure payload for more arguments 333 * for an ongoing arithmetic operation requested by the 334 * non-secure world. Simply return the arguments from the non- 335 * secure client in the original call. 336 */ 337 case TSP_GET_ARGS: 338 if (ns) 339 SMC_RET1(handle, SMC_UNK); 340 341 /* Get a reference to the non-secure context */ 342 ns_cpu_context = cm_get_context(mpidr, NON_SECURE); 343 assert(ns_cpu_context); 344 ns_gp_regs = get_gpregs_ctx(ns_cpu_context); 345 346 SMC_RET2(handle, read_ctx_reg(ns_gp_regs, CTX_GPREG_X1), 347 read_ctx_reg(ns_gp_regs, CTX_GPREG_X2)); 348 349 case TOS_CALL_COUNT: 350 /* 351 * Return the number of service function IDs implemented to 352 * provide service to non-secure 353 */ 354 SMC_RET1(handle, TSP_NUM_FID); 355 356 case TOS_UID: 357 /* Return TSP UID to the caller */ 358 SMC_UUID_RET(handle, tsp_uuid); 359 360 case TOS_CALL_VERSION: 361 /* Return the version of current implementation */ 362 SMC_RET2(handle, TSP_VERSION_MAJOR, TSP_VERSION_MINOR); 363 364 default: 365 break; 366 } 367 368 SMC_RET1(handle, SMC_UNK); 369 } 370 371 /* Define a SPD runtime service descriptor */ 372 DECLARE_RT_SVC( 373 spd, 374 375 OEN_TOS_START, 376 OEN_TOS_END, 377 SMC_TYPE_FAST, 378 tspd_setup, 379 tspd_smc_handler 380 ); 381