1/* 2 * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7#include <arch.h> 8#include <asm_macros.S> 9#include <tsp.h> 10#include <xlat_tables_defs.h> 11#include "../tsp_private.h" 12 13 14 .globl tsp_entrypoint 15 .globl tsp_vector_table 16 17 18 19 /* --------------------------------------------- 20 * Populate the params in x0-x7 from the pointer 21 * to the smc args structure in x0. 22 * --------------------------------------------- 23 */ 24 .macro restore_args_call_smc 25 ldp x6, x7, [x0, #TSP_ARG6] 26 ldp x4, x5, [x0, #TSP_ARG4] 27 ldp x2, x3, [x0, #TSP_ARG2] 28 ldp x0, x1, [x0, #TSP_ARG0] 29 smc #0 30 .endm 31 32 .macro save_eret_context reg1 reg2 33 mrs \reg1, elr_el1 34 mrs \reg2, spsr_el1 35 stp \reg1, \reg2, [sp, #-0x10]! 36 stp x30, x18, [sp, #-0x10]! 37 .endm 38 39 .macro restore_eret_context reg1 reg2 40 ldp x30, x18, [sp], #0x10 41 ldp \reg1, \reg2, [sp], #0x10 42 msr elr_el1, \reg1 43 msr spsr_el1, \reg2 44 .endm 45 46func tsp_entrypoint _align=3 47 48 /* --------------------------------------------- 49 * Set the exception vector to something sane. 50 * --------------------------------------------- 51 */ 52 adr x0, tsp_exceptions 53 msr vbar_el1, x0 54 isb 55 56 /* --------------------------------------------- 57 * Enable the SError interrupt now that the 58 * exception vectors have been setup. 59 * --------------------------------------------- 60 */ 61 msr daifclr, #DAIF_ABT_BIT 62 63 /* --------------------------------------------- 64 * Enable the instruction cache, stack pointer 65 * and data access alignment checks 66 * --------------------------------------------- 67 */ 68 mov x1, #(SCTLR_I_BIT | SCTLR_A_BIT | SCTLR_SA_BIT) 69 mrs x0, sctlr_el1 70 orr x0, x0, x1 71 msr sctlr_el1, x0 72 isb 73 74 /* --------------------------------------------- 75 * Invalidate the RW memory used by the BL32 76 * image. This includes the data and NOBITS 77 * sections. This is done to safeguard against 78 * possible corruption of this memory by dirty 79 * cache lines in a system cache as a result of 80 * use by an earlier boot loader stage. 81 * --------------------------------------------- 82 */ 83 adr x0, __RW_START__ 84 adr x1, __RW_END__ 85 sub x1, x1, x0 86 bl inv_dcache_range 87 88 /* --------------------------------------------- 89 * Zero out NOBITS sections. There are 2 of them: 90 * - the .bss section; 91 * - the coherent memory section. 92 * --------------------------------------------- 93 */ 94 ldr x0, =__BSS_START__ 95 ldr x1, =__BSS_SIZE__ 96 bl zeromem 97 98#if USE_COHERENT_MEM 99 ldr x0, =__COHERENT_RAM_START__ 100 ldr x1, =__COHERENT_RAM_UNALIGNED_SIZE__ 101 bl zeromem 102#endif 103 104 /* -------------------------------------------- 105 * Allocate a stack whose memory will be marked 106 * as Normal-IS-WBWA when the MMU is enabled. 107 * There is no risk of reading stale stack 108 * memory after enabling the MMU as only the 109 * primary cpu is running at the moment. 110 * -------------------------------------------- 111 */ 112 bl plat_set_my_stack 113 114 /* --------------------------------------------- 115 * Initialize the stack protector canary before 116 * any C code is called. 117 * --------------------------------------------- 118 */ 119#if STACK_PROTECTOR_ENABLED 120 bl update_stack_protector_canary 121#endif 122 123 /* --------------------------------------------- 124 * Perform early platform setup & platform 125 * specific early arch. setup e.g. mmu setup 126 * --------------------------------------------- 127 */ 128 bl tsp_early_platform_setup 129 bl tsp_plat_arch_setup 130 131 /* --------------------------------------------- 132 * Jump to main function. 133 * --------------------------------------------- 134 */ 135 bl tsp_main 136 137 /* --------------------------------------------- 138 * Tell TSPD that we are done initialising 139 * --------------------------------------------- 140 */ 141 mov x1, x0 142 mov x0, #TSP_ENTRY_DONE 143 smc #0 144 145tsp_entrypoint_panic: 146 b tsp_entrypoint_panic 147endfunc tsp_entrypoint 148 149 150 /* ------------------------------------------- 151 * Table of entrypoint vectors provided to the 152 * TSPD for the various entrypoints 153 * ------------------------------------------- 154 */ 155func tsp_vector_table 156 b tsp_yield_smc_entry 157 b tsp_fast_smc_entry 158 b tsp_cpu_on_entry 159 b tsp_cpu_off_entry 160 b tsp_cpu_resume_entry 161 b tsp_cpu_suspend_entry 162 b tsp_sel1_intr_entry 163 b tsp_system_off_entry 164 b tsp_system_reset_entry 165 b tsp_abort_yield_smc_entry 166endfunc tsp_vector_table 167 168 /*--------------------------------------------- 169 * This entrypoint is used by the TSPD when this 170 * cpu is to be turned off through a CPU_OFF 171 * psci call to ask the TSP to perform any 172 * bookeeping necessary. In the current 173 * implementation, the TSPD expects the TSP to 174 * re-initialise its state so nothing is done 175 * here except for acknowledging the request. 176 * --------------------------------------------- 177 */ 178func tsp_cpu_off_entry 179 bl tsp_cpu_off_main 180 restore_args_call_smc 181endfunc tsp_cpu_off_entry 182 183 /*--------------------------------------------- 184 * This entrypoint is used by the TSPD when the 185 * system is about to be switched off (through 186 * a SYSTEM_OFF psci call) to ask the TSP to 187 * perform any necessary bookkeeping. 188 * --------------------------------------------- 189 */ 190func tsp_system_off_entry 191 bl tsp_system_off_main 192 restore_args_call_smc 193endfunc tsp_system_off_entry 194 195 /*--------------------------------------------- 196 * This entrypoint is used by the TSPD when the 197 * system is about to be reset (through a 198 * SYSTEM_RESET psci call) to ask the TSP to 199 * perform any necessary bookkeeping. 200 * --------------------------------------------- 201 */ 202func tsp_system_reset_entry 203 bl tsp_system_reset_main 204 restore_args_call_smc 205endfunc tsp_system_reset_entry 206 207 /*--------------------------------------------- 208 * This entrypoint is used by the TSPD when this 209 * cpu is turned on using a CPU_ON psci call to 210 * ask the TSP to initialise itself i.e. setup 211 * the mmu, stacks etc. Minimal architectural 212 * state will be initialised by the TSPD when 213 * this function is entered i.e. Caches and MMU 214 * will be turned off, the execution state 215 * will be aarch64 and exceptions masked. 216 * --------------------------------------------- 217 */ 218func tsp_cpu_on_entry 219 /* --------------------------------------------- 220 * Set the exception vector to something sane. 221 * --------------------------------------------- 222 */ 223 adr x0, tsp_exceptions 224 msr vbar_el1, x0 225 isb 226 227 /* Enable the SError interrupt */ 228 msr daifclr, #DAIF_ABT_BIT 229 230 /* --------------------------------------------- 231 * Enable the instruction cache, stack pointer 232 * and data access alignment checks 233 * --------------------------------------------- 234 */ 235 mov x1, #(SCTLR_I_BIT | SCTLR_A_BIT | SCTLR_SA_BIT) 236 mrs x0, sctlr_el1 237 orr x0, x0, x1 238 msr sctlr_el1, x0 239 isb 240 241 /* -------------------------------------------- 242 * Give ourselves a stack whose memory will be 243 * marked as Normal-IS-WBWA when the MMU is 244 * enabled. 245 * -------------------------------------------- 246 */ 247 bl plat_set_my_stack 248 249 /* -------------------------------------------- 250 * Enable MMU and D-caches together. 251 * -------------------------------------------- 252 */ 253 mov x0, #0 254 bl bl32_plat_enable_mmu 255 256 /* --------------------------------------------- 257 * Enter C runtime to perform any remaining 258 * book keeping 259 * --------------------------------------------- 260 */ 261 bl tsp_cpu_on_main 262 restore_args_call_smc 263 264 /* Should never reach here */ 265tsp_cpu_on_entry_panic: 266 b tsp_cpu_on_entry_panic 267endfunc tsp_cpu_on_entry 268 269 /*--------------------------------------------- 270 * This entrypoint is used by the TSPD when this 271 * cpu is to be suspended through a CPU_SUSPEND 272 * psci call to ask the TSP to perform any 273 * bookeeping necessary. In the current 274 * implementation, the TSPD saves and restores 275 * the EL1 state. 276 * --------------------------------------------- 277 */ 278func tsp_cpu_suspend_entry 279 bl tsp_cpu_suspend_main 280 restore_args_call_smc 281endfunc tsp_cpu_suspend_entry 282 283 /*------------------------------------------------- 284 * This entrypoint is used by the TSPD to pass 285 * control for `synchronously` handling a S-EL1 286 * Interrupt which was triggered while executing 287 * in normal world. 'x0' contains a magic number 288 * which indicates this. TSPD expects control to 289 * be handed back at the end of interrupt 290 * processing. This is done through an SMC. 291 * The handover agreement is: 292 * 293 * 1. PSTATE.DAIF are set upon entry. 'x1' has 294 * the ELR_EL3 from the non-secure state. 295 * 2. TSP has to preserve the callee saved 296 * general purpose registers, SP_EL1/EL0 and 297 * LR. 298 * 3. TSP has to preserve the system and vfp 299 * registers (if applicable). 300 * 4. TSP can use 'x0-x18' to enable its C 301 * runtime. 302 * 5. TSP returns to TSPD using an SMC with 303 * 'x0' = TSP_HANDLED_S_EL1_INTR 304 * ------------------------------------------------ 305 */ 306func tsp_sel1_intr_entry 307#if DEBUG 308 mov_imm x2, TSP_HANDLE_SEL1_INTR_AND_RETURN 309 cmp x0, x2 310 b.ne tsp_sel1_int_entry_panic 311#endif 312 /*------------------------------------------------- 313 * Save any previous context needed to perform 314 * an exception return from S-EL1 e.g. context 315 * from a previous Non secure Interrupt. 316 * Update statistics and handle the S-EL1 317 * interrupt before returning to the TSPD. 318 * IRQ/FIQs are not enabled since that will 319 * complicate the implementation. Execution 320 * will be transferred back to the normal world 321 * in any case. The handler can return 0 322 * if the interrupt was handled or TSP_PREEMPTED 323 * if the expected interrupt was preempted 324 * by an interrupt that should be handled in EL3 325 * e.g. Group 0 interrupt in GICv3. In both 326 * the cases switch to EL3 using SMC with id 327 * TSP_HANDLED_S_EL1_INTR. Any other return value 328 * from the handler will result in panic. 329 * ------------------------------------------------ 330 */ 331 save_eret_context x2 x3 332 bl tsp_update_sync_sel1_intr_stats 333 bl tsp_common_int_handler 334 /* Check if the S-EL1 interrupt has been handled */ 335 cbnz x0, tsp_sel1_intr_check_preemption 336 b tsp_sel1_intr_return 337tsp_sel1_intr_check_preemption: 338 /* Check if the S-EL1 interrupt has been preempted */ 339 mov_imm x1, TSP_PREEMPTED 340 cmp x0, x1 341 b.ne tsp_sel1_int_entry_panic 342tsp_sel1_intr_return: 343 mov_imm x0, TSP_HANDLED_S_EL1_INTR 344 restore_eret_context x2 x3 345 smc #0 346 347 /* Should never reach here */ 348tsp_sel1_int_entry_panic: 349 no_ret plat_panic_handler 350endfunc tsp_sel1_intr_entry 351 352 /*--------------------------------------------- 353 * This entrypoint is used by the TSPD when this 354 * cpu resumes execution after an earlier 355 * CPU_SUSPEND psci call to ask the TSP to 356 * restore its saved context. In the current 357 * implementation, the TSPD saves and restores 358 * EL1 state so nothing is done here apart from 359 * acknowledging the request. 360 * --------------------------------------------- 361 */ 362func tsp_cpu_resume_entry 363 bl tsp_cpu_resume_main 364 restore_args_call_smc 365 366 /* Should never reach here */ 367 no_ret plat_panic_handler 368endfunc tsp_cpu_resume_entry 369 370 /*--------------------------------------------- 371 * This entrypoint is used by the TSPD to ask 372 * the TSP to service a fast smc request. 373 * --------------------------------------------- 374 */ 375func tsp_fast_smc_entry 376 bl tsp_smc_handler 377 restore_args_call_smc 378 379 /* Should never reach here */ 380 no_ret plat_panic_handler 381endfunc tsp_fast_smc_entry 382 383 /*--------------------------------------------- 384 * This entrypoint is used by the TSPD to ask 385 * the TSP to service a Yielding SMC request. 386 * We will enable preemption during execution 387 * of tsp_smc_handler. 388 * --------------------------------------------- 389 */ 390func tsp_yield_smc_entry 391 msr daifclr, #DAIF_FIQ_BIT | DAIF_IRQ_BIT 392 bl tsp_smc_handler 393 msr daifset, #DAIF_FIQ_BIT | DAIF_IRQ_BIT 394 restore_args_call_smc 395 396 /* Should never reach here */ 397 no_ret plat_panic_handler 398endfunc tsp_yield_smc_entry 399 400 /*--------------------------------------------------------------------- 401 * This entrypoint is used by the TSPD to abort a pre-empted Yielding 402 * SMC. It could be on behalf of non-secure world or because a CPU 403 * suspend/CPU off request needs to abort the preempted SMC. 404 * -------------------------------------------------------------------- 405 */ 406func tsp_abort_yield_smc_entry 407 408 /* 409 * Exceptions masking is already done by the TSPD when entering this 410 * hook so there is no need to do it here. 411 */ 412 413 /* Reset the stack used by the pre-empted SMC */ 414 bl plat_set_my_stack 415 416 /* 417 * Allow some cleanup such as releasing locks. 418 */ 419 bl tsp_abort_smc_handler 420 421 restore_args_call_smc 422 423 /* Should never reach here */ 424 bl plat_panic_handler 425endfunc tsp_abort_yield_smc_entry 426