Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2024 The Hafnium Authors. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style |
| 5 | * license that can be found in the LICENSE file or at |
| 6 | * https://opensource.org/licenses/BSD-3-Clause. |
| 7 | */ |
| 8 | |
| 9 | #include "hf/arch/gicv3.h" |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 10 | |
| 11 | #include "hf/api.h" |
| 12 | #include "hf/check.h" |
Karl Meakin | 902af08 | 2024-11-28 14:58:38 +0000 | [diff] [blame] | 13 | #include "hf/ffa.h" |
| 14 | #include "hf/ffa/interrupts.h" |
Karl Meakin | 936ec1e | 2025-01-31 13:17:11 +0000 | [diff] [blame^] | 15 | #include "hf/ffa/vm.h" |
| 16 | #include "hf/ffa_internal.h" |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 17 | #include "hf/plat/interrupts.h" |
| 18 | #include "hf/vm.h" |
| 19 | |
| 20 | void plat_ffa_vcpu_allow_interrupts(struct vcpu *current); |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 21 | |
Karl Meakin | 117c808 | 2024-12-04 16:03:28 +0000 | [diff] [blame] | 22 | bool ffa_cpu_cycles_run_forward(ffa_id_t vm_id, ffa_vcpu_index_t vcpu_idx, |
| 23 | struct ffa_value *ret) |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 24 | { |
| 25 | (void)vm_id; |
| 26 | (void)vcpu_idx; |
| 27 | (void)ret; |
| 28 | |
| 29 | return false; |
| 30 | } |
| 31 | |
| 32 | /** |
| 33 | * Check if current VM can resume target VM using FFA_RUN ABI. |
| 34 | */ |
Karl Meakin | 117c808 | 2024-12-04 16:03:28 +0000 | [diff] [blame] | 35 | bool ffa_cpu_cycles_run_checks(struct vcpu_locked current_locked, |
| 36 | ffa_id_t target_vm_id, ffa_vcpu_index_t vcpu_idx, |
| 37 | struct ffa_value *run_ret, struct vcpu **next) |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 38 | { |
| 39 | /* |
| 40 | * Under the Partition runtime model specified in FF-A v1.1-Beta0 spec, |
| 41 | * SP can invoke FFA_RUN to resume target SP. |
| 42 | */ |
| 43 | struct vcpu *target_vcpu; |
| 44 | struct vcpu *current = current_locked.vcpu; |
| 45 | bool ret = true; |
| 46 | struct vm *vm; |
| 47 | struct vcpu_locked target_locked; |
| 48 | struct two_vcpu_locked vcpus_locked; |
| 49 | |
| 50 | vm = vm_find(target_vm_id); |
| 51 | if (vm == NULL) { |
| 52 | return false; |
| 53 | } |
| 54 | |
| 55 | if (vm_is_mp(vm) && vm_is_mp(current->vm) && |
| 56 | vcpu_idx != cpu_index(current->cpu)) { |
| 57 | dlog_verbose("vcpu_idx (%d) != pcpu index (%zu)\n", vcpu_idx, |
| 58 | cpu_index(current->cpu)); |
| 59 | return false; |
| 60 | } |
| 61 | |
| 62 | target_vcpu = api_ffa_get_vm_vcpu(vm, current); |
| 63 | |
| 64 | vcpu_unlock(¤t_locked); |
| 65 | |
| 66 | /* Lock both vCPUs at once to avoid deadlock. */ |
| 67 | vcpus_locked = vcpu_lock_both(current, target_vcpu); |
| 68 | current_locked = vcpus_locked.vcpu1; |
| 69 | target_locked = vcpus_locked.vcpu2; |
| 70 | |
| 71 | /* Only the primary VM can turn ON a vCPU that is currently OFF. */ |
| 72 | if (!vm_is_primary(current->vm) && |
| 73 | target_vcpu->state == VCPU_STATE_OFF) { |
| 74 | run_ret->arg2 = FFA_DENIED; |
| 75 | ret = false; |
| 76 | goto out; |
| 77 | } |
| 78 | |
| 79 | /* |
| 80 | * An SPx can resume another SPy only when SPy is in PREEMPTED or |
| 81 | * BLOCKED state. |
| 82 | */ |
| 83 | if (vm_id_is_current_world(current->vm->id) && |
| 84 | vm_id_is_current_world(target_vm_id)) { |
| 85 | /* Target SP must be in preempted or blocked state. */ |
| 86 | if (target_vcpu->state != VCPU_STATE_PREEMPTED && |
| 87 | target_vcpu->state != VCPU_STATE_BLOCKED) { |
| 88 | run_ret->arg2 = FFA_DENIED; |
| 89 | ret = false; |
| 90 | goto out; |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | /* A SP cannot invoke FFA_RUN to resume a normal world VM. */ |
| 95 | if (!vm_id_is_current_world(target_vm_id)) { |
| 96 | run_ret->arg2 = FFA_DENIED; |
| 97 | ret = false; |
| 98 | goto out; |
| 99 | } |
| 100 | |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 101 | if (vm_id_is_current_world(current->vm->id)) { |
| 102 | /* |
| 103 | * Refer FF-A v1.1 EAC0 spec section 8.3.2.2.1 |
| 104 | * Signaling an Other S-Int in blocked state |
| 105 | */ |
| 106 | if (current->preempted_vcpu != NULL) { |
| 107 | /* |
| 108 | * After the target SP execution context has handled |
| 109 | * the interrupt, it uses the FFA_RUN ABI to resume |
| 110 | * the request due to which it had entered the blocked |
| 111 | * state earlier. |
| 112 | * Deny the state transition if the SP didnt perform the |
| 113 | * deactivation of the secure virtual interrupt. |
| 114 | */ |
| 115 | if (!vcpu_is_interrupt_queue_empty(current_locked)) { |
| 116 | run_ret->arg2 = FFA_DENIED; |
| 117 | ret = false; |
| 118 | goto out; |
| 119 | } |
| 120 | |
| 121 | /* |
| 122 | * Refer Figure 8.13 Scenario 1: Implementation choice: |
| 123 | * SPMC left all intermediate SP execution contexts in |
| 124 | * blocked state. Hence, SPMC now bypasses the |
| 125 | * intermediate these execution contexts and resumes the |
| 126 | * SP execution context that was originally preempted. |
| 127 | */ |
| 128 | *next = current->preempted_vcpu; |
| 129 | if (target_vcpu != current->preempted_vcpu) { |
| 130 | dlog_verbose("Skipping intermediate vCPUs\n"); |
| 131 | } |
| 132 | /* |
| 133 | * This flag should not have been set by SPMC when it |
| 134 | * signaled the virtual interrupt to the SP while SP was |
| 135 | * in WAITING or BLOCKED states. Refer the embedded |
| 136 | * comment in vcpu.h file for further description. |
| 137 | */ |
| 138 | assert(!current->requires_deactivate_call); |
| 139 | |
| 140 | /* |
| 141 | * Clear fields corresponding to secure interrupt |
| 142 | * handling. |
| 143 | */ |
| 144 | vcpu_secure_interrupt_complete(current_locked); |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | /* Check if a vCPU of SP is being resumed. */ |
| 149 | if (vm_id_is_current_world(target_vm_id)) { |
| 150 | /* |
| 151 | * A call chain cannot span CPUs. The target vCPU can only be |
| 152 | * resumed by FFA_RUN on present CPU. |
| 153 | */ |
| 154 | if ((target_vcpu->call_chain.prev_node != NULL || |
| 155 | target_vcpu->call_chain.next_node != NULL) && |
| 156 | (target_vcpu->cpu != current->cpu)) { |
| 157 | run_ret->arg2 = FFA_DENIED; |
| 158 | ret = false; |
| 159 | goto out; |
| 160 | } |
| 161 | |
| 162 | if (!vcpu_is_interrupt_queue_empty(target_locked)) { |
| 163 | /* |
| 164 | * Consider the following scenarios: a secure interrupt |
| 165 | * triggered in normal world and is targeted to an SP. |
| 166 | * Scenario A): The target SP's vCPU was preempted by a |
| 167 | * non secure interrupt. |
| 168 | * Scenario B): The target SP's vCPU was in blocked |
| 169 | * state after it yielded CPU cycles to |
| 170 | * normal world using FFA_YIELD. |
| 171 | * In both the scenarios, SPMC would have injected a |
| 172 | * virtual interrupt and set the appropriate flags after |
| 173 | * de-activating the secure physical interrupt. SPMC did |
| 174 | * not resume the target vCPU at that moment. |
| 175 | */ |
| 176 | assert(target_vcpu->state == VCPU_STATE_PREEMPTED || |
| 177 | target_vcpu->state == VCPU_STATE_BLOCKED); |
| 178 | assert(vcpu_interrupt_count_get(target_locked) > 0); |
| 179 | |
| 180 | /* |
| 181 | * This check is to ensure the target SP vCPU could |
| 182 | * only be a part of NWd scheduled call chain. FF-A v1.1 |
| 183 | * spec prohibits an SPMC scheduled call chain to be |
| 184 | * preempted by a non secure interrupt. |
| 185 | */ |
| 186 | CHECK(target_vcpu->scheduling_mode == NWD_MODE); |
| 187 | } |
| 188 | } |
| 189 | |
| 190 | out: |
| 191 | vcpu_unlock(&target_locked); |
| 192 | return ret; |
| 193 | } |
| 194 | |
| 195 | /** |
| 196 | * SPMC scheduled call chain is completely unwound. |
| 197 | */ |
| 198 | static void plat_ffa_exit_spmc_schedule_mode(struct vcpu_locked current_locked) |
| 199 | { |
| 200 | struct vcpu *current; |
| 201 | |
| 202 | current = current_locked.vcpu; |
| 203 | assert(current->call_chain.next_node == NULL); |
| 204 | CHECK(current->scheduling_mode == SPMC_MODE); |
| 205 | |
| 206 | current->scheduling_mode = NONE; |
| 207 | current->rt_model = RTM_NONE; |
| 208 | } |
| 209 | |
| 210 | /** |
| 211 | * A SP in running state could have been pre-empted by a secure interrupt. SPM |
| 212 | * would switch the execution to the vCPU of target SP responsible for interupt |
| 213 | * handling. Upon completion of interrupt handling, vCPU performs interrupt |
| 214 | * signal completion through FFA_MSG_WAIT ABI (provided it was in waiting state |
| 215 | * when interrupt was signaled). |
| 216 | * |
| 217 | * SPM then resumes the original SP that was initially pre-empted. |
| 218 | */ |
| 219 | static struct ffa_value plat_ffa_preempted_vcpu_resume( |
| 220 | struct vcpu_locked current_locked, struct vcpu **next) |
| 221 | { |
| 222 | struct ffa_value ffa_ret = (struct ffa_value){.func = FFA_MSG_WAIT_32}; |
| 223 | struct vcpu *target_vcpu; |
| 224 | struct vcpu *current = current_locked.vcpu; |
| 225 | struct vcpu_locked target_locked; |
| 226 | struct two_vcpu_locked vcpus_locked; |
| 227 | |
| 228 | CHECK(current->preempted_vcpu != NULL); |
| 229 | CHECK(current->preempted_vcpu->state == VCPU_STATE_PREEMPTED); |
| 230 | |
| 231 | target_vcpu = current->preempted_vcpu; |
| 232 | vcpu_unlock(¤t_locked); |
| 233 | |
| 234 | /* Lock both vCPUs at once to avoid deadlock. */ |
| 235 | vcpus_locked = vcpu_lock_both(current, target_vcpu); |
| 236 | current_locked = vcpus_locked.vcpu1; |
| 237 | target_locked = vcpus_locked.vcpu2; |
| 238 | |
| 239 | /* Reset the fields tracking secure interrupt processing. */ |
| 240 | vcpu_secure_interrupt_complete(current_locked); |
| 241 | |
| 242 | /* SPMC scheduled call chain is completely unwound. */ |
| 243 | plat_ffa_exit_spmc_schedule_mode(current_locked); |
| 244 | assert(current->call_chain.prev_node == NULL); |
| 245 | |
| 246 | current->state = VCPU_STATE_WAITING; |
| 247 | |
| 248 | vcpu_set_running(target_locked, NULL); |
| 249 | |
| 250 | vcpu_unlock(&target_locked); |
| 251 | |
| 252 | /* Restore interrupt priority mask. */ |
| 253 | plat_ffa_vcpu_allow_interrupts(current); |
| 254 | |
| 255 | /* The pre-empted vCPU should be run. */ |
| 256 | *next = target_vcpu; |
| 257 | |
| 258 | return ffa_ret; |
| 259 | } |
| 260 | |
| 261 | static struct ffa_value ffa_msg_wait_complete(struct vcpu_locked current_locked, |
| 262 | struct vcpu **next) |
| 263 | { |
| 264 | struct vcpu *current = current_locked.vcpu; |
| 265 | |
| 266 | current->scheduling_mode = NONE; |
| 267 | current->rt_model = RTM_NONE; |
| 268 | |
| 269 | /* Relinquish control back to the NWd. */ |
| 270 | *next = api_switch_to_other_world( |
| 271 | current_locked, (struct ffa_value){.func = FFA_MSG_WAIT_32}, |
| 272 | VCPU_STATE_WAITING); |
| 273 | |
| 274 | return api_ffa_interrupt_return(0); |
| 275 | } |
| 276 | |
| 277 | /** |
| 278 | * Deals with the common case of intercepting an FFA_MSG_WAIT call. |
| 279 | */ |
| 280 | static bool plat_ffa_msg_wait_intercept(struct vcpu_locked current_locked, |
| 281 | struct vcpu **next, |
| 282 | struct ffa_value *ffa_ret) |
| 283 | { |
| 284 | struct two_vcpu_locked both_vcpu_locks; |
| 285 | struct vcpu *current = current_locked.vcpu; |
| 286 | bool ret = false; |
| 287 | |
| 288 | assert(next != NULL); |
| 289 | assert(*next != NULL); |
| 290 | |
| 291 | vcpu_unlock(¤t_locked); |
| 292 | |
| 293 | both_vcpu_locks = vcpu_lock_both(current, *next); |
| 294 | |
| 295 | /* |
| 296 | * Check if there are any pending secure virtual interrupts to |
| 297 | * be handled. The `next` should have a pointer to the current |
| 298 | * vCPU. Intercept call will set `ret` to FFA_INTERRUPT and the |
| 299 | * respective interrupt id. |
| 300 | */ |
Karl Meakin | 117c808 | 2024-12-04 16:03:28 +0000 | [diff] [blame] | 301 | if (ffa_interrupts_intercept_call(both_vcpu_locks.vcpu1, |
| 302 | both_vcpu_locks.vcpu2, ffa_ret)) { |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 303 | *next = NULL; |
| 304 | ret = true; |
| 305 | } |
| 306 | |
| 307 | vcpu_unlock(&both_vcpu_locks.vcpu2); |
| 308 | |
| 309 | return ret; |
| 310 | } |
| 311 | |
Karl Meakin | 936ec1e | 2025-01-31 13:17:11 +0000 | [diff] [blame^] | 312 | static bool sp_boot_next(struct vcpu_locked current_locked, struct vcpu **next) |
| 313 | { |
| 314 | struct vcpu *vcpu_next = NULL; |
| 315 | struct vcpu *current = current_locked.vcpu; |
| 316 | struct vm *next_vm; |
| 317 | size_t cpu_indx = cpu_index(current->cpu); |
| 318 | |
| 319 | if (current->cpu->last_sp_initialized) { |
| 320 | return false; |
| 321 | } |
| 322 | |
| 323 | if (!atomic_load_explicit(¤t->vm->aborting, |
| 324 | memory_order_relaxed)) { |
| 325 | /* vCPU has just returned from successful initialization. */ |
| 326 | dlog_verbose( |
| 327 | "Initialized execution context of VM: %#x on CPU: %zu, " |
| 328 | "boot_order: %u\n", |
| 329 | current->vm->id, cpu_index(current->cpu), |
| 330 | current->vm->boot_order); |
| 331 | } |
| 332 | |
| 333 | if (cpu_index(current_locked.vcpu->cpu) == PRIMARY_CPU_IDX) { |
| 334 | next_vm = vm_get_next_boot(current->vm); |
| 335 | } else { |
| 336 | /* SP boot chain on secondary CPU. */ |
| 337 | next_vm = vm_get_next_boot_secondary_core(current->vm); |
| 338 | } |
| 339 | |
| 340 | current->state = VCPU_STATE_WAITING; |
| 341 | current->rt_model = RTM_NONE; |
| 342 | current->scheduling_mode = NONE; |
| 343 | |
| 344 | /* |
| 345 | * Pick next SP's vCPU to be booted. Once all SPs have booted |
| 346 | * (next_vm is NULL), then return execution to NWd. |
| 347 | */ |
| 348 | if (next_vm == NULL) { |
| 349 | current->cpu->last_sp_initialized = true; |
| 350 | goto out; |
| 351 | } |
| 352 | |
| 353 | vcpu_next = vm_get_vcpu(next_vm, cpu_indx); |
| 354 | |
| 355 | /* |
| 356 | * An SP's execution context needs to be bootstrapped if: |
| 357 | * - It has never been initialized before. |
| 358 | * - Or it was turned off when the CPU, on which it was pinned, was |
| 359 | * powered down. |
| 360 | */ |
| 361 | if (vcpu_next->rt_model == RTM_SP_INIT || |
| 362 | vcpu_next->state == VCPU_STATE_OFF) { |
| 363 | vcpu_next->rt_model = RTM_SP_INIT; |
| 364 | arch_regs_reset(vcpu_next); |
| 365 | vcpu_next->cpu = current->cpu; |
| 366 | vcpu_next->state = VCPU_STATE_RUNNING; |
| 367 | vcpu_next->regs_available = false; |
| 368 | vcpu_set_phys_core_idx(vcpu_next); |
| 369 | arch_regs_set_pc_arg(&vcpu_next->regs, |
| 370 | vcpu_next->vm->secondary_ep, 0ULL); |
| 371 | |
| 372 | if (cpu_index(current_locked.vcpu->cpu) == PRIMARY_CPU_IDX) { |
| 373 | /* |
| 374 | * Boot information is passed by the SPMC to the SP's |
| 375 | * execution context only on the primary CPU. |
| 376 | */ |
| 377 | vcpu_set_boot_info_gp_reg(vcpu_next); |
| 378 | } |
| 379 | |
| 380 | *next = vcpu_next; |
| 381 | |
| 382 | return true; |
| 383 | } |
| 384 | out: |
| 385 | dlog_notice("Finished bootstrapping all SPs on CPU%lx\n", cpu_indx); |
| 386 | return false; |
| 387 | } |
| 388 | |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 389 | /** |
| 390 | * The invocation of FFA_MSG_WAIT at secure virtual FF-A instance is compliant |
| 391 | * with FF-A v1.1 EAC0 specification. It only performs the state transition |
| 392 | * from RUNNING to WAITING for the following Partition runtime models: |
| 393 | * RTM_FFA_RUN, RTM_SEC_INTERRUPT, RTM_SP_INIT. |
| 394 | */ |
Karl Meakin | 117c808 | 2024-12-04 16:03:28 +0000 | [diff] [blame] | 395 | struct ffa_value ffa_cpu_cycles_msg_wait_prepare( |
| 396 | struct vcpu_locked current_locked, struct vcpu **next) |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 397 | { |
| 398 | struct ffa_value ret = api_ffa_interrupt_return(0); |
| 399 | struct vcpu *current = current_locked.vcpu; |
| 400 | |
| 401 | switch (current->rt_model) { |
| 402 | case RTM_SP_INIT: |
| 403 | if (!sp_boot_next(current_locked, next)) { |
| 404 | ret = ffa_msg_wait_complete(current_locked, next); |
| 405 | |
| 406 | if (plat_ffa_msg_wait_intercept(current_locked, next, |
| 407 | &ret)) { |
| 408 | } |
| 409 | } |
| 410 | break; |
| 411 | case RTM_SEC_INTERRUPT: |
| 412 | /* |
| 413 | * Either resume the preempted SP or complete the FFA_MSG_WAIT. |
| 414 | */ |
| 415 | assert(current->preempted_vcpu != NULL); |
| 416 | plat_ffa_preempted_vcpu_resume(current_locked, next); |
| 417 | |
| 418 | if (plat_ffa_msg_wait_intercept(current_locked, next, &ret)) { |
| 419 | break; |
| 420 | } |
| 421 | |
| 422 | /* |
| 423 | * If CPU cycles were allocated through FFA_RUN interface, |
| 424 | * allow the interrupts(if they were masked earlier) before |
| 425 | * returning control to NWd. |
| 426 | */ |
| 427 | plat_ffa_vcpu_allow_interrupts(current); |
| 428 | break; |
| 429 | case RTM_FFA_RUN: |
| 430 | ret = ffa_msg_wait_complete(current_locked, next); |
| 431 | |
| 432 | if (plat_ffa_msg_wait_intercept(current_locked, next, &ret)) { |
| 433 | break; |
| 434 | } |
| 435 | |
| 436 | /* |
| 437 | * If CPU cycles were allocated through FFA_RUN interface, |
| 438 | * allow the interrupts(if they were masked earlier) before |
| 439 | * returning control to NWd. |
| 440 | */ |
| 441 | plat_ffa_vcpu_allow_interrupts(current); |
| 442 | |
| 443 | break; |
| 444 | default: |
| 445 | panic("%s: unexpected runtime model %x for [%x %x]", |
| 446 | current->rt_model, current->vm->id, |
| 447 | cpu_index(current->cpu)); |
| 448 | } |
| 449 | |
| 450 | vcpu_unlock(¤t_locked); |
| 451 | |
| 452 | return ret; |
| 453 | } |
| 454 | |
| 455 | /** |
| 456 | * Enforce action of an SP in response to non-secure or other-secure interrupt |
| 457 | * by changing the priority mask. Effectively, physical interrupts shall not |
| 458 | * trigger which has the same effect as queueing interrupts. |
| 459 | */ |
| 460 | static void plat_ffa_vcpu_queue_interrupts( |
| 461 | struct vcpu_locked receiver_vcpu_locked) |
| 462 | { |
| 463 | struct vcpu *receiver_vcpu = receiver_vcpu_locked.vcpu; |
| 464 | uint8_t current_priority; |
| 465 | |
| 466 | /* Save current value of priority mask. */ |
| 467 | current_priority = plat_interrupts_get_priority_mask(); |
| 468 | receiver_vcpu->prev_interrupt_priority = current_priority; |
| 469 | |
| 470 | if (receiver_vcpu->vm->other_s_interrupts_action == |
| 471 | OTHER_S_INT_ACTION_QUEUED || |
| 472 | receiver_vcpu->scheduling_mode == SPMC_MODE) { |
| 473 | /* |
| 474 | * If secure interrupts not masked yet, mask them now. We could |
| 475 | * enter SPMC scheduled mode when an EL3 SPMD Logical partition |
| 476 | * sends a direct request, and we are making the IMPDEF choice |
| 477 | * to mask interrupts when such a situation occurs. This keeps |
| 478 | * design simple. |
| 479 | */ |
| 480 | if (current_priority > SWD_MASK_ALL_INT) { |
| 481 | plat_interrupts_set_priority_mask(SWD_MASK_ALL_INT); |
| 482 | } |
| 483 | } else if (receiver_vcpu->vm->ns_interrupts_action == |
| 484 | NS_ACTION_QUEUED) { |
| 485 | /* If non secure interrupts not masked yet, mask them now. */ |
| 486 | if (current_priority > SWD_MASK_NS_INT) { |
| 487 | plat_interrupts_set_priority_mask(SWD_MASK_NS_INT); |
| 488 | } |
| 489 | } |
| 490 | } |
| 491 | |
| 492 | /* |
| 493 | * Initialize the scheduling mode and/or Partition Runtime model of the target |
| 494 | * SP upon being resumed by an FFA_RUN ABI. |
| 495 | */ |
Karl Meakin | 117c808 | 2024-12-04 16:03:28 +0000 | [diff] [blame] | 496 | void ffa_cpu_cycles_init_schedule_mode_ffa_runeld_prepare( |
| 497 | struct vcpu_locked current_locked, struct vcpu_locked target_locked) |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 498 | { |
| 499 | struct vcpu *vcpu = target_locked.vcpu; |
| 500 | struct vcpu *current = current_locked.vcpu; |
| 501 | |
| 502 | /* |
| 503 | * Scenario 1 in Table 8.4; Therefore SPMC could be resuming a vCPU |
| 504 | * that was part of NWd scheduled mode. |
| 505 | */ |
| 506 | CHECK(vcpu->scheduling_mode != SPMC_MODE); |
| 507 | |
| 508 | /* Section 8.2.3 bullet 4.2 of spec FF-A v1.1 EAC0. */ |
| 509 | if (vcpu->state == VCPU_STATE_WAITING) { |
| 510 | assert(vcpu->rt_model == RTM_SP_INIT || |
| 511 | vcpu->rt_model == RTM_NONE); |
| 512 | vcpu->rt_model = RTM_FFA_RUN; |
| 513 | |
| 514 | if (!vm_id_is_current_world(current->vm->id) || |
| 515 | (current->scheduling_mode == NWD_MODE)) { |
| 516 | vcpu->scheduling_mode = NWD_MODE; |
| 517 | } |
| 518 | } else { |
| 519 | /* SP vCPU would have been pre-empted earlier or blocked. */ |
| 520 | CHECK(vcpu->state == VCPU_STATE_PREEMPTED || |
| 521 | vcpu->state == VCPU_STATE_BLOCKED); |
| 522 | } |
| 523 | |
| 524 | plat_ffa_vcpu_queue_interrupts(target_locked); |
| 525 | } |
| 526 | |
| 527 | /* |
| 528 | * Prepare to yield execution back to the VM/SP that allocated CPU cycles and |
| 529 | * move to BLOCKED state. If the CPU cycles were allocated to the current |
| 530 | * execution context by the SPMC to handle secure virtual interrupt, then |
| 531 | * FFA_YIELD invocation is essentially a no-op. |
| 532 | */ |
Karl Meakin | 117c808 | 2024-12-04 16:03:28 +0000 | [diff] [blame] | 533 | struct ffa_value ffa_cpu_cycles_yield_prepare(struct vcpu_locked current_locked, |
| 534 | struct vcpu **next, |
| 535 | uint32_t timeout_low, |
| 536 | uint32_t timeout_high) |
Karl Meakin | 5a365d3 | 2024-11-08 23:55:03 +0000 | [diff] [blame] | 537 | { |
| 538 | struct ffa_value ret_args = (struct ffa_value){.func = FFA_SUCCESS_32}; |
| 539 | struct vcpu *current = current_locked.vcpu; |
| 540 | struct ffa_value ret = { |
| 541 | .func = FFA_YIELD_32, |
| 542 | .arg1 = ffa_vm_vcpu(current->vm->id, vcpu_index(current)), |
| 543 | .arg2 = timeout_low, |
| 544 | .arg3 = timeout_high, |
| 545 | }; |
| 546 | |
| 547 | switch (current->rt_model) { |
| 548 | case RTM_FFA_DIR_REQ: |
| 549 | assert(current->direct_request_origin.vm_id != |
| 550 | HF_INVALID_VM_ID); |
| 551 | if (current->call_chain.prev_node == NULL) { |
| 552 | /* |
| 553 | * Relinquish cycles to the NWd VM that sent direct |
| 554 | * request message to the current SP. |
| 555 | */ |
| 556 | *next = api_switch_to_other_world(current_locked, ret, |
| 557 | VCPU_STATE_BLOCKED); |
| 558 | } else { |
| 559 | /* |
| 560 | * Relinquish cycles to the SP that sent direct request |
| 561 | * message to the current SP. |
| 562 | */ |
| 563 | *next = api_switch_to_vm( |
| 564 | current_locked, ret, VCPU_STATE_BLOCKED, |
| 565 | current->direct_request_origin.vm_id); |
| 566 | } |
| 567 | break; |
| 568 | case RTM_SEC_INTERRUPT: { |
| 569 | /* |
| 570 | * SPMC does not implement a scheduler needed to resume the |
| 571 | * current vCPU upon timeout expiration. Hence, SPMC makes the |
| 572 | * implementation defined choice to treat FFA_YIELD invocation |
| 573 | * as a no-op if the SP execution context is in the secure |
| 574 | * interrupt runtime model. This does not violate FF-A spec as |
| 575 | * the spec does not mandate timeout to be honored. Moreover, |
| 576 | * timeout specified by an endpoint is just a hint to the |
| 577 | * partition manager which allocated CPU cycles. |
| 578 | * Resume the current vCPU. |
| 579 | */ |
| 580 | *next = NULL; |
| 581 | break; |
| 582 | } |
| 583 | default: |
| 584 | CHECK(current->rt_model == RTM_FFA_RUN); |
| 585 | *next = api_switch_to_primary(current_locked, ret, |
| 586 | VCPU_STATE_BLOCKED); |
| 587 | break; |
| 588 | } |
| 589 | |
| 590 | /* |
| 591 | * Before yielding CPU cycles, allow the interrupts(if they were |
| 592 | * masked earlier). |
| 593 | */ |
| 594 | if (*next != NULL) { |
| 595 | plat_ffa_vcpu_allow_interrupts(current); |
| 596 | } |
| 597 | |
| 598 | return ret_args; |
| 599 | } |
Karl Meakin | 936ec1e | 2025-01-31 13:17:11 +0000 | [diff] [blame^] | 600 | |
| 601 | static bool is_predecessor_in_call_chain(struct vcpu_locked current_locked, |
| 602 | struct vcpu_locked target_locked) |
| 603 | { |
| 604 | struct vcpu *prev_node; |
| 605 | struct vcpu *current = current_locked.vcpu; |
| 606 | struct vcpu *target = target_locked.vcpu; |
| 607 | |
| 608 | assert(current != NULL); |
| 609 | assert(target != NULL); |
| 610 | |
| 611 | prev_node = current->call_chain.prev_node; |
| 612 | |
| 613 | while (prev_node != NULL) { |
| 614 | if (prev_node == target) { |
| 615 | return true; |
| 616 | } |
| 617 | |
| 618 | /* The target vCPU is not it's immediate predecessor. */ |
| 619 | prev_node = prev_node->call_chain.prev_node; |
| 620 | } |
| 621 | |
| 622 | /* Search terminated. Reached start of call chain. */ |
| 623 | return false; |
| 624 | } |
| 625 | |
| 626 | /** |
| 627 | * Validates the Runtime model for FFA_RUN. Refer to section 7.2 of the FF-A |
| 628 | * v1.1 EAC0 spec. |
| 629 | */ |
| 630 | static bool plat_ffa_check_rtm_ffa_run(struct vcpu_locked current_locked, |
| 631 | struct vcpu_locked locked_vcpu, |
| 632 | uint32_t func, |
| 633 | enum vcpu_state *next_state) |
| 634 | { |
| 635 | switch (func) { |
| 636 | case FFA_MSG_SEND_DIRECT_REQ_64: |
| 637 | case FFA_MSG_SEND_DIRECT_REQ_32: |
| 638 | case FFA_MSG_SEND_DIRECT_REQ2_64: |
| 639 | /* Fall through. */ |
| 640 | case FFA_RUN_32: { |
| 641 | /* Rules 1,2 section 7.2 EAC0 spec. */ |
| 642 | if (is_predecessor_in_call_chain(current_locked, locked_vcpu)) { |
| 643 | return false; |
| 644 | } |
| 645 | *next_state = VCPU_STATE_BLOCKED; |
| 646 | return true; |
| 647 | } |
| 648 | case FFA_MSG_WAIT_32: |
| 649 | /* Rule 4 section 7.2 EAC0 spec. Fall through. */ |
| 650 | *next_state = VCPU_STATE_WAITING; |
| 651 | return true; |
| 652 | case FFA_YIELD_32: |
| 653 | /* Rule 5 section 7.2 EAC0 spec. */ |
| 654 | *next_state = VCPU_STATE_BLOCKED; |
| 655 | return true; |
| 656 | case FFA_MSG_SEND_DIRECT_RESP_64: |
| 657 | case FFA_MSG_SEND_DIRECT_RESP_32: |
| 658 | case FFA_MSG_SEND_DIRECT_RESP2_64: |
| 659 | /* Rule 3 section 7.2 EAC0 spec. Fall through. */ |
| 660 | default: |
| 661 | /* Deny state transitions by default. */ |
| 662 | return false; |
| 663 | } |
| 664 | } |
| 665 | |
| 666 | /** |
| 667 | * Validates the Runtime model for FFA_MSG_SEND_DIRECT_REQ and |
| 668 | * FFA_MSG_SEND_DIRECT_REQ2. Refer to section 8.3 of the FF-A |
| 669 | * v1.2 spec. |
| 670 | */ |
| 671 | static bool plat_ffa_check_rtm_ffa_dir_req(struct vcpu_locked current_locked, |
| 672 | struct vcpu_locked locked_vcpu, |
| 673 | ffa_id_t receiver_vm_id, |
| 674 | uint32_t func, |
| 675 | enum vcpu_state *next_state) |
| 676 | { |
| 677 | switch (func) { |
| 678 | case FFA_MSG_SEND_DIRECT_REQ_64: |
| 679 | case FFA_MSG_SEND_DIRECT_REQ_32: |
| 680 | case FFA_MSG_SEND_DIRECT_REQ2_64: |
| 681 | /* Fall through. */ |
| 682 | case FFA_RUN_32: { |
| 683 | /* Rules 1,2. */ |
| 684 | if (is_predecessor_in_call_chain(current_locked, locked_vcpu)) { |
| 685 | return false; |
| 686 | } |
| 687 | |
| 688 | *next_state = VCPU_STATE_BLOCKED; |
| 689 | return true; |
| 690 | } |
| 691 | case FFA_MSG_SEND_DIRECT_RESP_64: |
| 692 | case FFA_MSG_SEND_DIRECT_RESP_32: { |
| 693 | case FFA_MSG_SEND_DIRECT_RESP2_64: |
| 694 | /* Rule 3. */ |
| 695 | if (current_locked.vcpu->direct_request_origin.vm_id == |
| 696 | receiver_vm_id) { |
| 697 | *next_state = VCPU_STATE_WAITING; |
| 698 | return true; |
| 699 | } |
| 700 | |
| 701 | return false; |
| 702 | } |
| 703 | case FFA_YIELD_32: |
| 704 | /* Rule 3, section 8.3 of FF-A v1.2 spec. */ |
| 705 | *next_state = VCPU_STATE_BLOCKED; |
| 706 | return true; |
| 707 | case FFA_MSG_WAIT_32: |
| 708 | /* Rule 4. Fall through. */ |
| 709 | default: |
| 710 | /* Deny state transitions by default. */ |
| 711 | return false; |
| 712 | } |
| 713 | } |
| 714 | |
| 715 | /** |
| 716 | * Validates the Runtime model for Secure interrupt handling. Refer to section |
| 717 | * 8.4 of the FF-A v1.2 ALP0 spec. |
| 718 | */ |
| 719 | static bool plat_ffa_check_rtm_sec_interrupt(struct vcpu_locked current_locked, |
| 720 | struct vcpu_locked locked_vcpu, |
| 721 | uint32_t func, |
| 722 | enum vcpu_state *next_state) |
| 723 | { |
| 724 | struct vcpu *current = current_locked.vcpu; |
| 725 | struct vcpu *vcpu = locked_vcpu.vcpu; |
| 726 | |
| 727 | CHECK(current->scheduling_mode == SPMC_MODE); |
| 728 | |
| 729 | switch (func) { |
| 730 | case FFA_MSG_SEND_DIRECT_REQ_64: |
| 731 | case FFA_MSG_SEND_DIRECT_REQ_32: |
| 732 | case FFA_MSG_SEND_DIRECT_REQ2_64: |
| 733 | /* Rule 3. */ |
| 734 | *next_state = VCPU_STATE_BLOCKED; |
| 735 | return true; |
| 736 | case FFA_RUN_32: { |
| 737 | /* Rule 6. */ |
| 738 | if (vcpu->state == VCPU_STATE_PREEMPTED) { |
| 739 | *next_state = VCPU_STATE_BLOCKED; |
| 740 | return true; |
| 741 | } |
| 742 | |
| 743 | return false; |
| 744 | } |
| 745 | case FFA_MSG_WAIT_32: |
| 746 | /* Rule 2. */ |
| 747 | *next_state = VCPU_STATE_WAITING; |
| 748 | return true; |
| 749 | case FFA_YIELD_32: |
| 750 | /* Rule 3, section 8.4 of FF-A v1.2 spec. */ |
| 751 | *next_state = VCPU_STATE_BLOCKED; |
| 752 | return true; |
| 753 | case FFA_MSG_SEND_DIRECT_RESP_64: |
| 754 | case FFA_MSG_SEND_DIRECT_RESP_32: |
| 755 | case FFA_MSG_SEND_DIRECT_RESP2_64: |
| 756 | /* Rule 5. Fall through. */ |
| 757 | default: |
| 758 | /* Deny state transitions by default. */ |
| 759 | return false; |
| 760 | } |
| 761 | } |
| 762 | |
| 763 | /** |
| 764 | * Validates the Runtime model for SP initialization. Refer to section |
| 765 | * 8.3 of the FF-A v1.2 ALP0 spec. |
| 766 | */ |
| 767 | static bool plat_ffa_check_rtm_sp_init(struct vcpu_locked locked_vcpu, |
| 768 | uint32_t func, |
| 769 | enum vcpu_state *next_state) |
| 770 | { |
| 771 | switch (func) { |
| 772 | case FFA_MSG_SEND_DIRECT_REQ_64: |
| 773 | case FFA_MSG_SEND_DIRECT_REQ_32: |
| 774 | case FFA_MSG_SEND_DIRECT_REQ2_64: { |
| 775 | struct vcpu *vcpu = locked_vcpu.vcpu; |
| 776 | |
| 777 | assert(vcpu != NULL); |
| 778 | /* Rule 1. */ |
| 779 | if (vcpu->rt_model != RTM_SP_INIT) { |
| 780 | *next_state = VCPU_STATE_BLOCKED; |
| 781 | return true; |
| 782 | } |
| 783 | |
| 784 | return false; |
| 785 | } |
| 786 | case FFA_MSG_WAIT_32: |
| 787 | /* Rule 2. Fall through. */ |
| 788 | case FFA_ERROR_32: |
| 789 | /* Rule 3. */ |
| 790 | *next_state = VCPU_STATE_WAITING; |
| 791 | return true; |
| 792 | case FFA_YIELD_32: |
| 793 | /* Rule 4. Fall through. */ |
| 794 | case FFA_RUN_32: |
| 795 | /* Rule 6. Fall through. */ |
| 796 | case FFA_MSG_SEND_DIRECT_RESP_64: |
| 797 | case FFA_MSG_SEND_DIRECT_RESP_32: |
| 798 | case FFA_MSG_SEND_DIRECT_RESP2_64: |
| 799 | /* Rule 5. Fall through. */ |
| 800 | default: |
| 801 | /* Deny state transitions by default. */ |
| 802 | return false; |
| 803 | } |
| 804 | } |
| 805 | |
| 806 | /** |
| 807 | * Check if the runtime model (state machine) of the current SP supports the |
| 808 | * given FF-A ABI invocation. If yes, next_state represents the state to which |
| 809 | * the current vcpu would transition upon the FF-A ABI invocation as determined |
| 810 | * by the Partition runtime model. |
| 811 | */ |
| 812 | bool ffa_cpu_cycles_check_runtime_state_transition( |
| 813 | struct vcpu_locked current_locked, ffa_id_t vm_id, |
| 814 | ffa_id_t receiver_vm_id, struct vcpu_locked locked_vcpu, uint32_t func, |
| 815 | enum vcpu_state *next_state) |
| 816 | { |
| 817 | bool allowed = false; |
| 818 | struct vcpu *current = current_locked.vcpu; |
| 819 | |
| 820 | assert(current != NULL); |
| 821 | |
| 822 | /* Perform state transition checks only for Secure Partitions. */ |
| 823 | if (!vm_id_is_current_world(vm_id)) { |
| 824 | return true; |
| 825 | } |
| 826 | |
| 827 | switch (current->rt_model) { |
| 828 | case RTM_FFA_RUN: |
| 829 | allowed = plat_ffa_check_rtm_ffa_run( |
| 830 | current_locked, locked_vcpu, func, next_state); |
| 831 | break; |
| 832 | case RTM_FFA_DIR_REQ: |
| 833 | allowed = plat_ffa_check_rtm_ffa_dir_req( |
| 834 | current_locked, locked_vcpu, receiver_vm_id, func, |
| 835 | next_state); |
| 836 | break; |
| 837 | case RTM_SEC_INTERRUPT: |
| 838 | allowed = plat_ffa_check_rtm_sec_interrupt( |
| 839 | current_locked, locked_vcpu, func, next_state); |
| 840 | break; |
| 841 | case RTM_SP_INIT: |
| 842 | allowed = plat_ffa_check_rtm_sp_init(locked_vcpu, func, |
| 843 | next_state); |
| 844 | break; |
| 845 | default: |
| 846 | dlog_error( |
| 847 | "Illegal Runtime Model specified by SP%x on CPU%zx\n", |
| 848 | current->vm->id, cpu_index(current->cpu)); |
| 849 | allowed = false; |
| 850 | break; |
| 851 | } |
| 852 | |
| 853 | if (!allowed) { |
| 854 | dlog_verbose("State transition denied\n"); |
| 855 | } |
| 856 | |
| 857 | return allowed; |
| 858 | } |
| 859 | |
| 860 | /* |
| 861 | * Handle FFA_ERROR_32 call according to the given error code. |
| 862 | * |
| 863 | * Error codes other than FFA_ABORTED, and cases of FFA_ABORTED not |
| 864 | * in RTM_SP_INIT runtime model, not implemented. Refer to section 8.5 |
| 865 | * of FF-A 1.2 spec. |
| 866 | */ |
| 867 | struct ffa_value plat_ffa_error_32(struct vcpu *current, struct vcpu **next, |
| 868 | enum ffa_error error_code) |
| 869 | { |
| 870 | struct vcpu_locked current_locked; |
| 871 | struct vm_locked vm_locked; |
| 872 | enum partition_runtime_model rt_model; |
| 873 | struct ffa_value ret = api_ffa_interrupt_return(0); |
| 874 | |
| 875 | vm_locked = vm_lock(current->vm); |
| 876 | current_locked = vcpu_lock(current); |
| 877 | rt_model = current_locked.vcpu->rt_model; |
| 878 | |
| 879 | if (error_code == FFA_ABORTED && rt_model == RTM_SP_INIT) { |
| 880 | dlog_error("Aborting SP %#x from vCPU %u\n", current->vm->id, |
| 881 | vcpu_index(current)); |
| 882 | |
| 883 | atomic_store_explicit(¤t->vm->aborting, true, |
| 884 | memory_order_relaxed); |
| 885 | |
| 886 | ffa_vm_free_resources(vm_locked); |
| 887 | |
| 888 | if (sp_boot_next(current_locked, next)) { |
| 889 | goto out; |
| 890 | } |
| 891 | |
| 892 | /* |
| 893 | * Relinquish control back to the NWd. Return |
| 894 | * FFA_MSG_WAIT_32 to indicate to SPMD that SPMC |
| 895 | * has successfully finished initialization. |
| 896 | */ |
| 897 | *next = api_switch_to_other_world( |
| 898 | current_locked, |
| 899 | (struct ffa_value){.func = FFA_MSG_WAIT_32}, |
| 900 | VCPU_STATE_ABORTED); |
| 901 | |
| 902 | goto out; |
| 903 | } |
| 904 | ret = ffa_error(FFA_NOT_SUPPORTED); |
| 905 | out: |
| 906 | vcpu_unlock(¤t_locked); |
| 907 | vm_unlock(&vm_locked); |
| 908 | return ret; |
| 909 | } |