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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 | // SPDX-License-Identifier: GPL-2.0-only /* * kernel/power/suspend.c - Suspend to RAM and standby functionality. * * Copyright (c) 2003 Patrick Mochel * Copyright (c) 2003 Open Source Development Lab * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. */ #define pr_fmt(fmt) "PM: " fmt #include <linux/string.h> #include <linux/delay.h> #include <linux/errno.h> #include <linux/init.h> #include <linux/console.h> #include <linux/cpu.h> #include <linux/cpuidle.h> #include <linux/gfp.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/list.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/export.h> #include <linux/suspend.h> #include <linux/syscore_ops.h> #include <linux/swait.h> #include <linux/ftrace.h> #include <trace/events/power.h> #include <linux/compiler.h> #include <linux/moduleparam.h> #include "power.h" const char * const pm_labels[] = { [PM_SUSPEND_TO_IDLE] = "freeze", [PM_SUSPEND_STANDBY] = "standby", [PM_SUSPEND_MEM] = "mem", }; const char *pm_states[PM_SUSPEND_MAX]; static const char * const mem_sleep_labels[] = { [PM_SUSPEND_TO_IDLE] = "s2idle", [PM_SUSPEND_STANDBY] = "shallow", [PM_SUSPEND_MEM] = "deep", }; const char *mem_sleep_states[PM_SUSPEND_MAX]; suspend_state_t mem_sleep_current = PM_SUSPEND_TO_IDLE; suspend_state_t mem_sleep_default = PM_SUSPEND_MAX; suspend_state_t pm_suspend_target_state; EXPORT_SYMBOL_GPL(pm_suspend_target_state); unsigned int pm_suspend_global_flags; EXPORT_SYMBOL_GPL(pm_suspend_global_flags); static const struct platform_suspend_ops *suspend_ops; static const struct platform_s2idle_ops *s2idle_ops; static DECLARE_SWAIT_QUEUE_HEAD(s2idle_wait_head); enum s2idle_states __read_mostly s2idle_state; static DEFINE_RAW_SPINLOCK(s2idle_lock); /** * pm_suspend_default_s2idle - Check if suspend-to-idle is the default suspend. * * Return 'true' if suspend-to-idle has been selected as the default system * suspend method. */ bool pm_suspend_default_s2idle(void) { return mem_sleep_current == PM_SUSPEND_TO_IDLE; } EXPORT_SYMBOL_GPL(pm_suspend_default_s2idle); void s2idle_set_ops(const struct platform_s2idle_ops *ops) { unsigned int sleep_flags; sleep_flags = lock_system_sleep(); s2idle_ops = ops; unlock_system_sleep(sleep_flags); } static void s2idle_begin(void) { s2idle_state = S2IDLE_STATE_NONE; } static void s2idle_enter(void) { trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, true); raw_spin_lock_irq(&s2idle_lock); if (pm_wakeup_pending()) goto out; s2idle_state = S2IDLE_STATE_ENTER; raw_spin_unlock_irq(&s2idle_lock); cpus_read_lock(); /* Push all the CPUs into the idle loop. */ wake_up_all_idle_cpus(); /* Make the current CPU wait so it can enter the idle loop too. */ swait_event_exclusive(s2idle_wait_head, s2idle_state == S2IDLE_STATE_WAKE); /* * Kick all CPUs to ensure that they resume their timers and restore * consistent system state. */ wake_up_all_idle_cpus(); cpus_read_unlock(); raw_spin_lock_irq(&s2idle_lock); out: s2idle_state = S2IDLE_STATE_NONE; raw_spin_unlock_irq(&s2idle_lock); trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, false); } static void s2idle_loop(void) { pm_pr_dbg("suspend-to-idle\n"); /* * Suspend-to-idle equals: * frozen processes + suspended devices + idle processors. * Thus s2idle_enter() should be called right after all devices have * been suspended. * * Wakeups during the noirq suspend of devices may be spurious, so try * to avoid them upfront. */ for (;;) { if (s2idle_ops && s2idle_ops->wake) { if (s2idle_ops->wake()) break; } else if (pm_wakeup_pending()) { break; } if (s2idle_ops && s2idle_ops->check) s2idle_ops->check(); s2idle_enter(); } pm_pr_dbg("resume from suspend-to-idle\n"); } void s2idle_wake(void) { unsigned long flags; raw_spin_lock_irqsave(&s2idle_lock, flags); if (s2idle_state > S2IDLE_STATE_NONE) { s2idle_state = S2IDLE_STATE_WAKE; swake_up_one(&s2idle_wait_head); } raw_spin_unlock_irqrestore(&s2idle_lock, flags); } EXPORT_SYMBOL_GPL(s2idle_wake); static bool valid_state(suspend_state_t state) { /* * The PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states require low-level * support and need to be valid to the low-level implementation. * * No ->valid() or ->enter() callback implies that none are valid. */ return suspend_ops && suspend_ops->valid && suspend_ops->valid(state) && suspend_ops->enter; } void __init pm_states_init(void) { /* "mem" and "freeze" are always present in /sys/power/state. */ pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM]; pm_states[PM_SUSPEND_TO_IDLE] = pm_labels[PM_SUSPEND_TO_IDLE]; /* * Suspend-to-idle should be supported even without any suspend_ops, * initialize mem_sleep_states[] accordingly here. */ mem_sleep_states[PM_SUSPEND_TO_IDLE] = mem_sleep_labels[PM_SUSPEND_TO_IDLE]; } static int __init mem_sleep_default_setup(char *str) { suspend_state_t state; for (state = PM_SUSPEND_TO_IDLE; state <= PM_SUSPEND_MEM; state++) if (mem_sleep_labels[state] && !strcmp(str, mem_sleep_labels[state])) { mem_sleep_default = state; mem_sleep_current = state; break; } return 1; } __setup("mem_sleep_default=", mem_sleep_default_setup); /** * suspend_set_ops - Set the global suspend method table. * @ops: Suspend operations to use. */ void suspend_set_ops(const struct platform_suspend_ops *ops) { unsigned int sleep_flags; sleep_flags = lock_system_sleep(); suspend_ops = ops; if (valid_state(PM_SUSPEND_STANDBY)) { mem_sleep_states[PM_SUSPEND_STANDBY] = mem_sleep_labels[PM_SUSPEND_STANDBY]; pm_states[PM_SUSPEND_STANDBY] = pm_labels[PM_SUSPEND_STANDBY]; if (mem_sleep_default == PM_SUSPEND_STANDBY) mem_sleep_current = PM_SUSPEND_STANDBY; } if (valid_state(PM_SUSPEND_MEM)) { mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM]; if (mem_sleep_default >= PM_SUSPEND_MEM) mem_sleep_current = PM_SUSPEND_MEM; } unlock_system_sleep(sleep_flags); } EXPORT_SYMBOL_GPL(suspend_set_ops); /** * suspend_valid_only_mem - Generic memory-only valid callback. * @state: Target system sleep state. * * Platform drivers that implement mem suspend only and only need to check for * that in their .valid() callback can use this instead of rolling their own * .valid() callback. */ int suspend_valid_only_mem(suspend_state_t state) { return state == PM_SUSPEND_MEM; } EXPORT_SYMBOL_GPL(suspend_valid_only_mem); static bool sleep_state_supported(suspend_state_t state) { return state == PM_SUSPEND_TO_IDLE || (valid_state(state) && !cxl_mem_active()); } static int platform_suspend_prepare(suspend_state_t state) { return state != PM_SUSPEND_TO_IDLE && suspend_ops->prepare ? suspend_ops->prepare() : 0; } static int platform_suspend_prepare_late(suspend_state_t state) { return state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->prepare ? s2idle_ops->prepare() : 0; } static int platform_suspend_prepare_noirq(suspend_state_t state) { if (state == PM_SUSPEND_TO_IDLE) return s2idle_ops && s2idle_ops->prepare_late ? s2idle_ops->prepare_late() : 0; return suspend_ops->prepare_late ? suspend_ops->prepare_late() : 0; } static void platform_resume_noirq(suspend_state_t state) { if (state == PM_SUSPEND_TO_IDLE) { if (s2idle_ops && s2idle_ops->restore_early) s2idle_ops->restore_early(); } else if (suspend_ops->wake) { suspend_ops->wake(); } } static void platform_resume_early(suspend_state_t state) { if (state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->restore) s2idle_ops->restore(); } static void platform_resume_finish(suspend_state_t state) { if (state != PM_SUSPEND_TO_IDLE && suspend_ops->finish) suspend_ops->finish(); } static int platform_suspend_begin(suspend_state_t state) { if (state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->begin) return s2idle_ops->begin(); else if (suspend_ops && suspend_ops->begin) return suspend_ops->begin(state); else return 0; } static void platform_resume_end(suspend_state_t state) { if (state == PM_SUSPEND_TO_IDLE && s2idle_ops && s2idle_ops->end) s2idle_ops->end(); else if (suspend_ops && suspend_ops->end) suspend_ops->end(); } static void platform_recover(suspend_state_t state) { if (state != PM_SUSPEND_TO_IDLE && suspend_ops->recover) suspend_ops->recover(); } static bool platform_suspend_again(suspend_state_t state) { return state != PM_SUSPEND_TO_IDLE && suspend_ops->suspend_again ? suspend_ops->suspend_again() : false; } #ifdef CONFIG_PM_DEBUG static unsigned int pm_test_delay = 5; module_param(pm_test_delay, uint, 0644); MODULE_PARM_DESC(pm_test_delay, "Number of seconds to wait before resuming from suspend test"); #endif static int suspend_test(int level) { #ifdef CONFIG_PM_DEBUG if (pm_test_level == level) { pr_info("suspend debug: Waiting for %d second(s).\n", pm_test_delay); mdelay(pm_test_delay * 1000); return 1; } #endif /* !CONFIG_PM_DEBUG */ return 0; } /** * suspend_prepare - Prepare for entering system sleep state. * @state: Target system sleep state. * * Common code run for every system sleep state that can be entered (except for * hibernation). Run suspend notifiers, allocate the "suspend" console and * freeze processes. */ static int suspend_prepare(suspend_state_t state) { int error; if (!sleep_state_supported(state)) return -EPERM; pm_prepare_console(); error = pm_notifier_call_chain_robust(PM_SUSPEND_PREPARE, PM_POST_SUSPEND); if (error) goto Restore; trace_suspend_resume(TPS("freeze_processes"), 0, true); error = suspend_freeze_processes(); trace_suspend_resume(TPS("freeze_processes"), 0, false); if (!error) return 0; suspend_stats.failed_freeze++; dpm_save_failed_step(SUSPEND_FREEZE); pm_notifier_call_chain(PM_POST_SUSPEND); Restore: pm_restore_console(); return error; } /* default implementation */ void __weak arch_suspend_disable_irqs(void) { local_irq_disable(); } /* default implementation */ void __weak arch_suspend_enable_irqs(void) { local_irq_enable(); } /** * suspend_enter - Make the system enter the given sleep state. * @state: System sleep state to enter. * @wakeup: Returns information that the sleep state should not be re-entered. * * This function should be called after devices have been suspended. */ static int suspend_enter(suspend_state_t state, bool *wakeup) { int error; error = platform_suspend_prepare(state); if (error) goto Platform_finish; error = dpm_suspend_late(PMSG_SUSPEND); if (error) { pr_err("late suspend of devices failed\n"); goto Platform_finish; } error = platform_suspend_prepare_late(state); if (error) goto Devices_early_resume; error = dpm_suspend_noirq(PMSG_SUSPEND); if (error) { pr_err("noirq suspend of devices failed\n"); goto Platform_early_resume; } error = platform_suspend_prepare_noirq(state); if (error) goto Platform_wake; if (suspend_test(TEST_PLATFORM)) goto Platform_wake; if (state == PM_SUSPEND_TO_IDLE) { s2idle_loop(); goto Platform_wake; } error = pm_sleep_disable_secondary_cpus(); if (error || suspend_test(TEST_CPUS)) goto Enable_cpus; arch_suspend_disable_irqs(); BUG_ON(!irqs_disabled()); system_state = SYSTEM_SUSPEND; error = syscore_suspend(); if (!error) { *wakeup = pm_wakeup_pending(); if (!(suspend_test(TEST_CORE) || *wakeup)) { trace_suspend_resume(TPS("machine_suspend"), state, true); error = suspend_ops->enter(state); trace_suspend_resume(TPS("machine_suspend"), state, false); } else if (*wakeup) { error = -EBUSY; } syscore_resume(); } system_state = SYSTEM_RUNNING; arch_suspend_enable_irqs(); BUG_ON(irqs_disabled()); Enable_cpus: pm_sleep_enable_secondary_cpus(); Platform_wake: platform_resume_noirq(state); dpm_resume_noirq(PMSG_RESUME); Platform_early_resume: platform_resume_early(state); Devices_early_resume: dpm_resume_early(PMSG_RESUME); Platform_finish: platform_resume_finish(state); return error; } /** * suspend_devices_and_enter - Suspend devices and enter system sleep state. * @state: System sleep state to enter. */ int suspend_devices_and_enter(suspend_state_t state) { int error; bool wakeup = false; if (!sleep_state_supported(state)) return -ENOSYS; pm_suspend_target_state = state; if (state == PM_SUSPEND_TO_IDLE) pm_set_suspend_no_platform(); error = platform_suspend_begin(state); if (error) goto Close; suspend_console(); suspend_test_start(); error = dpm_suspend_start(PMSG_SUSPEND); if (error) { pr_err("Some devices failed to suspend, or early wake event detected\n"); goto Recover_platform; } suspend_test_finish("suspend devices"); if (suspend_test(TEST_DEVICES)) goto Recover_platform; do { error = suspend_enter(state, &wakeup); } while (!error && !wakeup && platform_suspend_again(state)); Resume_devices: suspend_test_start(); dpm_resume_end(PMSG_RESUME); suspend_test_finish("resume devices"); trace_suspend_resume(TPS("resume_console"), state, true); resume_console(); trace_suspend_resume(TPS("resume_console"), state, false); Close: platform_resume_end(state); pm_suspend_target_state = PM_SUSPEND_ON; return error; Recover_platform: platform_recover(state); goto Resume_devices; } /** * suspend_finish - Clean up before finishing the suspend sequence. * * Call platform code to clean up, restart processes, and free the console that * we've allocated. This routine is not called for hibernation. */ static void suspend_finish(void) { suspend_thaw_processes(); pm_notifier_call_chain(PM_POST_SUSPEND); pm_restore_console(); } /** * enter_state - Do common work needed to enter system sleep state. * @state: System sleep state to enter. * * Make sure that no one else is trying to put the system into a sleep state. * Fail if that's not the case. Otherwise, prepare for system suspend, make the * system enter the given sleep state and clean up after wakeup. */ static int enter_state(suspend_state_t state) { int error; trace_suspend_resume(TPS("suspend_enter"), state, true); if (state == PM_SUSPEND_TO_IDLE) { #ifdef CONFIG_PM_DEBUG if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) { pr_warn("Unsupported test mode for suspend to idle, please choose none/freezer/devices/platform.\n"); return -EAGAIN; } #endif } else if (!valid_state(state)) { return -EINVAL; } if (!mutex_trylock(&system_transition_mutex)) return -EBUSY; if (state == PM_SUSPEND_TO_IDLE) s2idle_begin(); if (sync_on_suspend_enabled) { trace_suspend_resume(TPS("sync_filesystems"), 0, true); ksys_sync_helper(); trace_suspend_resume(TPS("sync_filesystems"), 0, false); } pm_pr_dbg("Preparing system for sleep (%s)\n", mem_sleep_labels[state]); pm_suspend_clear_flags(); error = suspend_prepare(state); if (error) goto Unlock; if (suspend_test(TEST_FREEZER)) goto Finish; trace_suspend_resume(TPS("suspend_enter"), state, false); pm_pr_dbg("Suspending system (%s)\n", mem_sleep_labels[state]); pm_restrict_gfp_mask(); error = suspend_devices_and_enter(state); pm_restore_gfp_mask(); Finish: events_check_enabled = false; pm_pr_dbg("Finishing wakeup.\n"); suspend_finish(); Unlock: mutex_unlock(&system_transition_mutex); return error; } /** * pm_suspend - Externally visible function for suspending the system. * @state: System sleep state to enter. * * Check if the value of @state represents one of the supported states, * execute enter_state() and update system suspend statistics. */ int pm_suspend(suspend_state_t state) { int error; if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX) return -EINVAL; pr_info("suspend entry (%s)\n", mem_sleep_labels[state]); error = enter_state(state); if (error) { suspend_stats.fail++; dpm_save_failed_errno(error); } else { suspend_stats.success++; } pr_info("suspend exit\n"); return error; } EXPORT_SYMBOL(pm_suspend); |