1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * processor_idle - idle state submodule to the ACPI processor driver 4 * 5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 7 * Copyright (C) 2004, 2005 Dominik Brodowski <linux@brodo.de> 8 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> 9 * - Added processor hotplug support 10 * Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> 11 * - Added support for C3 on SMP 12 */ 13 #define pr_fmt(fmt) "ACPI: " fmt 14 15 #include <linux/module.h> 16 #include <linux/acpi.h> 17 #include <linux/dmi.h> 18 #include <linux/sched.h> /* need_resched() */ 19 #include <linux/tick.h> 20 #include <linux/cpuidle.h> 21 #include <linux/cpu.h> 22 #include <acpi/processor.h> 23 24 /* 25 * Include the apic definitions for x86 to have the APIC timer related defines 26 * available also for UP (on SMP it gets magically included via linux/smp.h). 27 * asm/acpi.h is not an option, as it would require more include magic. Also 28 * creating an empty asm-ia64/apic.h would just trade pest vs. cholera. 29 */ 30 #ifdef CONFIG_X86 31 #include <asm/apic.h> 32 #endif 33 34 #define ACPI_PROCESSOR_CLASS "processor" 35 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 36 ACPI_MODULE_NAME("processor_idle"); 37 38 #define ACPI_IDLE_STATE_START (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX) ? 1 : 0) 39 40 static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER; 41 module_param(max_cstate, uint, 0000); 42 static unsigned int nocst __read_mostly; 43 module_param(nocst, uint, 0000); 44 static int bm_check_disable __read_mostly; 45 module_param(bm_check_disable, uint, 0000); 46 47 static unsigned int latency_factor __read_mostly = 2; 48 module_param(latency_factor, uint, 0644); 49 50 static DEFINE_PER_CPU(struct cpuidle_device *, acpi_cpuidle_device); 51 52 struct cpuidle_driver acpi_idle_driver = { 53 .name = "acpi_idle", 54 .owner = THIS_MODULE, 55 }; 56 57 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE 58 static 59 DEFINE_PER_CPU(struct acpi_processor_cx * [CPUIDLE_STATE_MAX], acpi_cstate); 60 61 static int disabled_by_idle_boot_param(void) 62 { 63 return boot_option_idle_override == IDLE_POLL || 64 boot_option_idle_override == IDLE_HALT; 65 } 66 67 /* 68 * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. 69 * For now disable this. Probably a bug somewhere else. 70 * 71 * To skip this limit, boot/load with a large max_cstate limit. 72 */ 73 static int set_max_cstate(const struct dmi_system_id *id) 74 { 75 if (max_cstate > ACPI_PROCESSOR_MAX_POWER) 76 return 0; 77 78 pr_notice("%s detected - limiting to C%ld max_cstate." 79 " Override with \"processor.max_cstate=%d\"\n", id->ident, 80 (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1); 81 82 max_cstate = (long)id->driver_data; 83 84 return 0; 85 } 86 87 static const struct dmi_system_id processor_power_dmi_table[] = { 88 { set_max_cstate, "Clevo 5600D", { 89 DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), 90 DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")}, 91 (void *)2}, 92 { set_max_cstate, "Pavilion zv5000", { 93 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 94 DMI_MATCH(DMI_PRODUCT_NAME,"Pavilion zv5000 (DS502A#ABA)")}, 95 (void *)1}, 96 { set_max_cstate, "Asus L8400B", { 97 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."), 98 DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")}, 99 (void *)1}, 100 {}, 101 }; 102 103 104 /* 105 * Callers should disable interrupts before the call and enable 106 * interrupts after return. 107 */ 108 static void __cpuidle acpi_safe_halt(void) 109 { 110 if (!tif_need_resched()) { 111 safe_halt(); 112 local_irq_disable(); 113 } 114 } 115 116 #ifdef ARCH_APICTIMER_STOPS_ON_C3 117 118 /* 119 * Some BIOS implementations switch to C3 in the published C2 state. 120 * This seems to be a common problem on AMD boxen, but other vendors 121 * are affected too. We pick the most conservative approach: we assume 122 * that the local APIC stops in both C2 and C3. 123 */ 124 static void lapic_timer_check_state(int state, struct acpi_processor *pr, 125 struct acpi_processor_cx *cx) 126 { 127 struct acpi_processor_power *pwr = &pr->power; 128 u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2; 129 130 if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT)) 131 return; 132 133 if (boot_cpu_has_bug(X86_BUG_AMD_APIC_C1E)) 134 type = ACPI_STATE_C1; 135 136 /* 137 * Check, if one of the previous states already marked the lapic 138 * unstable 139 */ 140 if (pwr->timer_broadcast_on_state < state) 141 return; 142 143 if (cx->type >= type) 144 pr->power.timer_broadcast_on_state = state; 145 } 146 147 static void __lapic_timer_propagate_broadcast(void *arg) 148 { 149 struct acpi_processor *pr = (struct acpi_processor *) arg; 150 151 if (pr->power.timer_broadcast_on_state < INT_MAX) 152 tick_broadcast_enable(); 153 else 154 tick_broadcast_disable(); 155 } 156 157 static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) 158 { 159 smp_call_function_single(pr->id, __lapic_timer_propagate_broadcast, 160 (void *)pr, 1); 161 } 162 163 /* Power(C) State timer broadcast control */ 164 static void lapic_timer_state_broadcast(struct acpi_processor *pr, 165 struct acpi_processor_cx *cx, 166 int broadcast) 167 { 168 int state = cx - pr->power.states; 169 170 if (state >= pr->power.timer_broadcast_on_state) { 171 if (broadcast) 172 tick_broadcast_enter(); 173 else 174 tick_broadcast_exit(); 175 } 176 } 177 178 #else 179 180 static void lapic_timer_check_state(int state, struct acpi_processor *pr, 181 struct acpi_processor_cx *cstate) { } 182 static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { } 183 static void lapic_timer_state_broadcast(struct acpi_processor *pr, 184 struct acpi_processor_cx *cx, 185 int broadcast) 186 { 187 } 188 189 #endif 190 191 #if defined(CONFIG_X86) 192 static void tsc_check_state(int state) 193 { 194 switch (boot_cpu_data.x86_vendor) { 195 case X86_VENDOR_HYGON: 196 case X86_VENDOR_AMD: 197 case X86_VENDOR_INTEL: 198 case X86_VENDOR_CENTAUR: 199 case X86_VENDOR_ZHAOXIN: 200 /* 201 * AMD Fam10h TSC will tick in all 202 * C/P/S0/S1 states when this bit is set. 203 */ 204 if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) 205 return; 206 207 /*FALL THROUGH*/ 208 default: 209 /* TSC could halt in idle, so notify users */ 210 if (state > ACPI_STATE_C1) 211 mark_tsc_unstable("TSC halts in idle"); 212 } 213 } 214 #else 215 static void tsc_check_state(int state) { return; } 216 #endif 217 218 static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) 219 { 220 221 if (!pr->pblk) 222 return -ENODEV; 223 224 /* if info is obtained from pblk/fadt, type equals state */ 225 pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; 226 pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; 227 228 #ifndef CONFIG_HOTPLUG_CPU 229 /* 230 * Check for P_LVL2_UP flag before entering C2 and above on 231 * an SMP system. 232 */ 233 if ((num_online_cpus() > 1) && 234 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) 235 return -ENODEV; 236 #endif 237 238 /* determine C2 and C3 address from pblk */ 239 pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; 240 pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; 241 242 /* determine latencies from FADT */ 243 pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.c2_latency; 244 pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.c3_latency; 245 246 /* 247 * FADT specified C2 latency must be less than or equal to 248 * 100 microseconds. 249 */ 250 if (acpi_gbl_FADT.c2_latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { 251 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 252 "C2 latency too large [%d]\n", acpi_gbl_FADT.c2_latency)); 253 /* invalidate C2 */ 254 pr->power.states[ACPI_STATE_C2].address = 0; 255 } 256 257 /* 258 * FADT supplied C3 latency must be less than or equal to 259 * 1000 microseconds. 260 */ 261 if (acpi_gbl_FADT.c3_latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { 262 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 263 "C3 latency too large [%d]\n", acpi_gbl_FADT.c3_latency)); 264 /* invalidate C3 */ 265 pr->power.states[ACPI_STATE_C3].address = 0; 266 } 267 268 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 269 "lvl2[0x%08x] lvl3[0x%08x]\n", 270 pr->power.states[ACPI_STATE_C2].address, 271 pr->power.states[ACPI_STATE_C3].address)); 272 273 snprintf(pr->power.states[ACPI_STATE_C2].desc, 274 ACPI_CX_DESC_LEN, "ACPI P_LVL2 IOPORT 0x%x", 275 pr->power.states[ACPI_STATE_C2].address); 276 snprintf(pr->power.states[ACPI_STATE_C3].desc, 277 ACPI_CX_DESC_LEN, "ACPI P_LVL3 IOPORT 0x%x", 278 pr->power.states[ACPI_STATE_C3].address); 279 280 return 0; 281 } 282 283 static int acpi_processor_get_power_info_default(struct acpi_processor *pr) 284 { 285 if (!pr->power.states[ACPI_STATE_C1].valid) { 286 /* set the first C-State to C1 */ 287 /* all processors need to support C1 */ 288 pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; 289 pr->power.states[ACPI_STATE_C1].valid = 1; 290 pr->power.states[ACPI_STATE_C1].entry_method = ACPI_CSTATE_HALT; 291 292 snprintf(pr->power.states[ACPI_STATE_C1].desc, 293 ACPI_CX_DESC_LEN, "ACPI HLT"); 294 } 295 /* the C0 state only exists as a filler in our array */ 296 pr->power.states[ACPI_STATE_C0].valid = 1; 297 return 0; 298 } 299 300 static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) 301 { 302 int ret; 303 304 if (nocst) 305 return -ENODEV; 306 307 ret = acpi_processor_evaluate_cst(pr->handle, pr->id, &pr->power); 308 if (ret) 309 return ret; 310 311 /* 312 * It is expected that there will be at least 2 states, C1 and 313 * something else (C2 or C3), so fail if that is not the case. 314 */ 315 if (pr->power.count < 2) 316 return -EFAULT; 317 318 pr->flags.has_cst = 1; 319 return 0; 320 } 321 322 static void acpi_processor_power_verify_c3(struct acpi_processor *pr, 323 struct acpi_processor_cx *cx) 324 { 325 static int bm_check_flag = -1; 326 static int bm_control_flag = -1; 327 328 329 if (!cx->address) 330 return; 331 332 /* 333 * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) 334 * DMA transfers are used by any ISA device to avoid livelock. 335 * Note that we could disable Type-F DMA (as recommended by 336 * the erratum), but this is known to disrupt certain ISA 337 * devices thus we take the conservative approach. 338 */ 339 else if (errata.piix4.fdma) { 340 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 341 "C3 not supported on PIIX4 with Type-F DMA\n")); 342 return; 343 } 344 345 /* All the logic here assumes flags.bm_check is same across all CPUs */ 346 if (bm_check_flag == -1) { 347 /* Determine whether bm_check is needed based on CPU */ 348 acpi_processor_power_init_bm_check(&(pr->flags), pr->id); 349 bm_check_flag = pr->flags.bm_check; 350 bm_control_flag = pr->flags.bm_control; 351 } else { 352 pr->flags.bm_check = bm_check_flag; 353 pr->flags.bm_control = bm_control_flag; 354 } 355 356 if (pr->flags.bm_check) { 357 if (!pr->flags.bm_control) { 358 if (pr->flags.has_cst != 1) { 359 /* bus mastering control is necessary */ 360 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 361 "C3 support requires BM control\n")); 362 return; 363 } else { 364 /* Here we enter C3 without bus mastering */ 365 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 366 "C3 support without BM control\n")); 367 } 368 } 369 } else { 370 /* 371 * WBINVD should be set in fadt, for C3 state to be 372 * supported on when bm_check is not required. 373 */ 374 if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) { 375 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 376 "Cache invalidation should work properly" 377 " for C3 to be enabled on SMP systems\n")); 378 return; 379 } 380 } 381 382 /* 383 * Otherwise we've met all of our C3 requirements. 384 * Normalize the C3 latency to expidite policy. Enable 385 * checking of bus mastering status (bm_check) so we can 386 * use this in our C3 policy 387 */ 388 cx->valid = 1; 389 390 /* 391 * On older chipsets, BM_RLD needs to be set 392 * in order for Bus Master activity to wake the 393 * system from C3. Newer chipsets handle DMA 394 * during C3 automatically and BM_RLD is a NOP. 395 * In either case, the proper way to 396 * handle BM_RLD is to set it and leave it set. 397 */ 398 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 1); 399 400 return; 401 } 402 403 static int acpi_processor_power_verify(struct acpi_processor *pr) 404 { 405 unsigned int i; 406 unsigned int working = 0; 407 408 pr->power.timer_broadcast_on_state = INT_MAX; 409 410 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 411 struct acpi_processor_cx *cx = &pr->power.states[i]; 412 413 switch (cx->type) { 414 case ACPI_STATE_C1: 415 cx->valid = 1; 416 break; 417 418 case ACPI_STATE_C2: 419 if (!cx->address) 420 break; 421 cx->valid = 1; 422 break; 423 424 case ACPI_STATE_C3: 425 acpi_processor_power_verify_c3(pr, cx); 426 break; 427 } 428 if (!cx->valid) 429 continue; 430 431 lapic_timer_check_state(i, pr, cx); 432 tsc_check_state(cx->type); 433 working++; 434 } 435 436 lapic_timer_propagate_broadcast(pr); 437 438 return (working); 439 } 440 441 static int acpi_processor_get_cstate_info(struct acpi_processor *pr) 442 { 443 unsigned int i; 444 int result; 445 446 447 /* NOTE: the idle thread may not be running while calling 448 * this function */ 449 450 /* Zero initialize all the C-states info. */ 451 memset(pr->power.states, 0, sizeof(pr->power.states)); 452 453 result = acpi_processor_get_power_info_cst(pr); 454 if (result == -ENODEV) 455 result = acpi_processor_get_power_info_fadt(pr); 456 457 if (result) 458 return result; 459 460 acpi_processor_get_power_info_default(pr); 461 462 pr->power.count = acpi_processor_power_verify(pr); 463 464 /* 465 * if one state of type C2 or C3 is available, mark this 466 * CPU as being "idle manageable" 467 */ 468 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { 469 if (pr->power.states[i].valid) { 470 pr->power.count = i; 471 if (pr->power.states[i].type >= ACPI_STATE_C2) 472 pr->flags.power = 1; 473 } 474 } 475 476 return 0; 477 } 478 479 /** 480 * acpi_idle_bm_check - checks if bus master activity was detected 481 */ 482 static int acpi_idle_bm_check(void) 483 { 484 u32 bm_status = 0; 485 486 if (bm_check_disable) 487 return 0; 488 489 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); 490 if (bm_status) 491 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1); 492 /* 493 * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect 494 * the true state of bus mastering activity; forcing us to 495 * manually check the BMIDEA bit of each IDE channel. 496 */ 497 else if (errata.piix4.bmisx) { 498 if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) 499 || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) 500 bm_status = 1; 501 } 502 return bm_status; 503 } 504 505 static void wait_for_freeze(void) 506 { 507 #ifdef CONFIG_X86 508 /* No delay is needed if we are in guest */ 509 if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) 510 return; 511 #endif 512 /* Dummy wait op - must do something useless after P_LVL2 read 513 because chipsets cannot guarantee that STPCLK# signal 514 gets asserted in time to freeze execution properly. */ 515 inl(acpi_gbl_FADT.xpm_timer_block.address); 516 } 517 518 /** 519 * acpi_idle_do_entry - enter idle state using the appropriate method 520 * @cx: cstate data 521 * 522 * Caller disables interrupt before call and enables interrupt after return. 523 */ 524 static void __cpuidle acpi_idle_do_entry(struct acpi_processor_cx *cx) 525 { 526 if (cx->entry_method == ACPI_CSTATE_FFH) { 527 /* Call into architectural FFH based C-state */ 528 acpi_processor_ffh_cstate_enter(cx); 529 } else if (cx->entry_method == ACPI_CSTATE_HALT) { 530 acpi_safe_halt(); 531 } else { 532 /* IO port based C-state */ 533 inb(cx->address); 534 wait_for_freeze(); 535 } 536 } 537 538 /** 539 * acpi_idle_play_dead - enters an ACPI state for long-term idle (i.e. off-lining) 540 * @dev: the target CPU 541 * @index: the index of suggested state 542 */ 543 static int acpi_idle_play_dead(struct cpuidle_device *dev, int index) 544 { 545 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); 546 547 ACPI_FLUSH_CPU_CACHE(); 548 549 while (1) { 550 551 if (cx->entry_method == ACPI_CSTATE_HALT) 552 safe_halt(); 553 else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) { 554 inb(cx->address); 555 wait_for_freeze(); 556 } else 557 return -ENODEV; 558 } 559 560 /* Never reached */ 561 return 0; 562 } 563 564 static bool acpi_idle_fallback_to_c1(struct acpi_processor *pr) 565 { 566 return IS_ENABLED(CONFIG_HOTPLUG_CPU) && !pr->flags.has_cst && 567 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED); 568 } 569 570 static int c3_cpu_count; 571 static DEFINE_RAW_SPINLOCK(c3_lock); 572 573 /** 574 * acpi_idle_enter_bm - enters C3 with proper BM handling 575 * @pr: Target processor 576 * @cx: Target state context 577 * @timer_bc: Whether or not to change timer mode to broadcast 578 */ 579 static void acpi_idle_enter_bm(struct acpi_processor *pr, 580 struct acpi_processor_cx *cx, bool timer_bc) 581 { 582 acpi_unlazy_tlb(smp_processor_id()); 583 584 /* 585 * Must be done before busmaster disable as we might need to 586 * access HPET ! 587 */ 588 if (timer_bc) 589 lapic_timer_state_broadcast(pr, cx, 1); 590 591 /* 592 * disable bus master 593 * bm_check implies we need ARB_DIS 594 * bm_control implies whether we can do ARB_DIS 595 * 596 * That leaves a case where bm_check is set and bm_control is 597 * not set. In that case we cannot do much, we enter C3 598 * without doing anything. 599 */ 600 if (pr->flags.bm_control) { 601 raw_spin_lock(&c3_lock); 602 c3_cpu_count++; 603 /* Disable bus master arbitration when all CPUs are in C3 */ 604 if (c3_cpu_count == num_online_cpus()) 605 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1); 606 raw_spin_unlock(&c3_lock); 607 } 608 609 acpi_idle_do_entry(cx); 610 611 /* Re-enable bus master arbitration */ 612 if (pr->flags.bm_control) { 613 raw_spin_lock(&c3_lock); 614 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); 615 c3_cpu_count--; 616 raw_spin_unlock(&c3_lock); 617 } 618 619 if (timer_bc) 620 lapic_timer_state_broadcast(pr, cx, 0); 621 } 622 623 static int acpi_idle_enter(struct cpuidle_device *dev, 624 struct cpuidle_driver *drv, int index) 625 { 626 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); 627 struct acpi_processor *pr; 628 629 pr = __this_cpu_read(processors); 630 if (unlikely(!pr)) 631 return -EINVAL; 632 633 if (cx->type != ACPI_STATE_C1) { 634 if (acpi_idle_fallback_to_c1(pr) && num_online_cpus() > 1) { 635 index = ACPI_IDLE_STATE_START; 636 cx = per_cpu(acpi_cstate[index], dev->cpu); 637 } else if (cx->type == ACPI_STATE_C3 && pr->flags.bm_check) { 638 if (cx->bm_sts_skip || !acpi_idle_bm_check()) { 639 acpi_idle_enter_bm(pr, cx, true); 640 return index; 641 } else if (drv->safe_state_index >= 0) { 642 index = drv->safe_state_index; 643 cx = per_cpu(acpi_cstate[index], dev->cpu); 644 } else { 645 acpi_safe_halt(); 646 return -EBUSY; 647 } 648 } 649 } 650 651 lapic_timer_state_broadcast(pr, cx, 1); 652 653 if (cx->type == ACPI_STATE_C3) 654 ACPI_FLUSH_CPU_CACHE(); 655 656 acpi_idle_do_entry(cx); 657 658 lapic_timer_state_broadcast(pr, cx, 0); 659 660 return index; 661 } 662 663 static void acpi_idle_enter_s2idle(struct cpuidle_device *dev, 664 struct cpuidle_driver *drv, int index) 665 { 666 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); 667 668 if (cx->type == ACPI_STATE_C3) { 669 struct acpi_processor *pr = __this_cpu_read(processors); 670 671 if (unlikely(!pr)) 672 return; 673 674 if (pr->flags.bm_check) { 675 acpi_idle_enter_bm(pr, cx, false); 676 return; 677 } else { 678 ACPI_FLUSH_CPU_CACHE(); 679 } 680 } 681 acpi_idle_do_entry(cx); 682 } 683 684 static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr, 685 struct cpuidle_device *dev) 686 { 687 int i, count = ACPI_IDLE_STATE_START; 688 struct acpi_processor_cx *cx; 689 690 if (max_cstate == 0) 691 max_cstate = 1; 692 693 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 694 cx = &pr->power.states[i]; 695 696 if (!cx->valid) 697 continue; 698 699 per_cpu(acpi_cstate[count], dev->cpu) = cx; 700 701 count++; 702 if (count == CPUIDLE_STATE_MAX) 703 break; 704 } 705 706 if (!count) 707 return -EINVAL; 708 709 return 0; 710 } 711 712 static int acpi_processor_setup_cstates(struct acpi_processor *pr) 713 { 714 int i, count; 715 struct acpi_processor_cx *cx; 716 struct cpuidle_state *state; 717 struct cpuidle_driver *drv = &acpi_idle_driver; 718 719 if (max_cstate == 0) 720 max_cstate = 1; 721 722 if (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX)) { 723 cpuidle_poll_state_init(drv); 724 count = 1; 725 } else { 726 count = 0; 727 } 728 729 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 730 cx = &pr->power.states[i]; 731 732 if (!cx->valid) 733 continue; 734 735 state = &drv->states[count]; 736 snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i); 737 strlcpy(state->desc, cx->desc, CPUIDLE_DESC_LEN); 738 state->exit_latency = cx->latency; 739 state->target_residency = cx->latency * latency_factor; 740 state->enter = acpi_idle_enter; 741 742 state->flags = 0; 743 if (cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2) { 744 state->enter_dead = acpi_idle_play_dead; 745 drv->safe_state_index = count; 746 } 747 /* 748 * Halt-induced C1 is not good for ->enter_s2idle, because it 749 * re-enables interrupts on exit. Moreover, C1 is generally not 750 * particularly interesting from the suspend-to-idle angle, so 751 * avoid C1 and the situations in which we may need to fall back 752 * to it altogether. 753 */ 754 if (cx->type != ACPI_STATE_C1 && !acpi_idle_fallback_to_c1(pr)) 755 state->enter_s2idle = acpi_idle_enter_s2idle; 756 757 count++; 758 if (count == CPUIDLE_STATE_MAX) 759 break; 760 } 761 762 drv->state_count = count; 763 764 if (!count) 765 return -EINVAL; 766 767 return 0; 768 } 769 770 static inline void acpi_processor_cstate_first_run_checks(void) 771 { 772 static int first_run; 773 774 if (first_run) 775 return; 776 dmi_check_system(processor_power_dmi_table); 777 max_cstate = acpi_processor_cstate_check(max_cstate); 778 if (max_cstate < ACPI_C_STATES_MAX) 779 pr_notice("ACPI: processor limited to max C-state %d\n", 780 max_cstate); 781 first_run++; 782 783 if (nocst) 784 return; 785 786 acpi_processor_claim_cst_control(); 787 } 788 #else 789 790 static inline int disabled_by_idle_boot_param(void) { return 0; } 791 static inline void acpi_processor_cstate_first_run_checks(void) { } 792 static int acpi_processor_get_cstate_info(struct acpi_processor *pr) 793 { 794 return -ENODEV; 795 } 796 797 static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr, 798 struct cpuidle_device *dev) 799 { 800 return -EINVAL; 801 } 802 803 static int acpi_processor_setup_cstates(struct acpi_processor *pr) 804 { 805 return -EINVAL; 806 } 807 808 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */ 809 810 struct acpi_lpi_states_array { 811 unsigned int size; 812 unsigned int composite_states_size; 813 struct acpi_lpi_state *entries; 814 struct acpi_lpi_state *composite_states[ACPI_PROCESSOR_MAX_POWER]; 815 }; 816 817 static int obj_get_integer(union acpi_object *obj, u32 *value) 818 { 819 if (obj->type != ACPI_TYPE_INTEGER) 820 return -EINVAL; 821 822 *value = obj->integer.value; 823 return 0; 824 } 825 826 static int acpi_processor_evaluate_lpi(acpi_handle handle, 827 struct acpi_lpi_states_array *info) 828 { 829 acpi_status status; 830 int ret = 0; 831 int pkg_count, state_idx = 1, loop; 832 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 833 union acpi_object *lpi_data; 834 struct acpi_lpi_state *lpi_state; 835 836 status = acpi_evaluate_object(handle, "_LPI", NULL, &buffer); 837 if (ACPI_FAILURE(status)) { 838 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _LPI, giving up\n")); 839 return -ENODEV; 840 } 841 842 lpi_data = buffer.pointer; 843 844 /* There must be at least 4 elements = 3 elements + 1 package */ 845 if (!lpi_data || lpi_data->type != ACPI_TYPE_PACKAGE || 846 lpi_data->package.count < 4) { 847 pr_debug("not enough elements in _LPI\n"); 848 ret = -ENODATA; 849 goto end; 850 } 851 852 pkg_count = lpi_data->package.elements[2].integer.value; 853 854 /* Validate number of power states. */ 855 if (pkg_count < 1 || pkg_count != lpi_data->package.count - 3) { 856 pr_debug("count given by _LPI is not valid\n"); 857 ret = -ENODATA; 858 goto end; 859 } 860 861 lpi_state = kcalloc(pkg_count, sizeof(*lpi_state), GFP_KERNEL); 862 if (!lpi_state) { 863 ret = -ENOMEM; 864 goto end; 865 } 866 867 info->size = pkg_count; 868 info->entries = lpi_state; 869 870 /* LPI States start at index 3 */ 871 for (loop = 3; state_idx <= pkg_count; loop++, state_idx++, lpi_state++) { 872 union acpi_object *element, *pkg_elem, *obj; 873 874 element = &lpi_data->package.elements[loop]; 875 if (element->type != ACPI_TYPE_PACKAGE || element->package.count < 7) 876 continue; 877 878 pkg_elem = element->package.elements; 879 880 obj = pkg_elem + 6; 881 if (obj->type == ACPI_TYPE_BUFFER) { 882 struct acpi_power_register *reg; 883 884 reg = (struct acpi_power_register *)obj->buffer.pointer; 885 if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && 886 reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) 887 continue; 888 889 lpi_state->address = reg->address; 890 lpi_state->entry_method = 891 reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE ? 892 ACPI_CSTATE_FFH : ACPI_CSTATE_SYSTEMIO; 893 } else if (obj->type == ACPI_TYPE_INTEGER) { 894 lpi_state->entry_method = ACPI_CSTATE_INTEGER; 895 lpi_state->address = obj->integer.value; 896 } else { 897 continue; 898 } 899 900 /* elements[7,8] skipped for now i.e. Residency/Usage counter*/ 901 902 obj = pkg_elem + 9; 903 if (obj->type == ACPI_TYPE_STRING) 904 strlcpy(lpi_state->desc, obj->string.pointer, 905 ACPI_CX_DESC_LEN); 906 907 lpi_state->index = state_idx; 908 if (obj_get_integer(pkg_elem + 0, &lpi_state->min_residency)) { 909 pr_debug("No min. residency found, assuming 10 us\n"); 910 lpi_state->min_residency = 10; 911 } 912 913 if (obj_get_integer(pkg_elem + 1, &lpi_state->wake_latency)) { 914 pr_debug("No wakeup residency found, assuming 10 us\n"); 915 lpi_state->wake_latency = 10; 916 } 917 918 if (obj_get_integer(pkg_elem + 2, &lpi_state->flags)) 919 lpi_state->flags = 0; 920 921 if (obj_get_integer(pkg_elem + 3, &lpi_state->arch_flags)) 922 lpi_state->arch_flags = 0; 923 924 if (obj_get_integer(pkg_elem + 4, &lpi_state->res_cnt_freq)) 925 lpi_state->res_cnt_freq = 1; 926 927 if (obj_get_integer(pkg_elem + 5, &lpi_state->enable_parent_state)) 928 lpi_state->enable_parent_state = 0; 929 } 930 931 acpi_handle_debug(handle, "Found %d power states\n", state_idx); 932 end: 933 kfree(buffer.pointer); 934 return ret; 935 } 936 937 /* 938 * flat_state_cnt - the number of composite LPI states after the process of flattening 939 */ 940 static int flat_state_cnt; 941 942 /** 943 * combine_lpi_states - combine local and parent LPI states to form a composite LPI state 944 * 945 * @local: local LPI state 946 * @parent: parent LPI state 947 * @result: composite LPI state 948 */ 949 static bool combine_lpi_states(struct acpi_lpi_state *local, 950 struct acpi_lpi_state *parent, 951 struct acpi_lpi_state *result) 952 { 953 if (parent->entry_method == ACPI_CSTATE_INTEGER) { 954 if (!parent->address) /* 0 means autopromotable */ 955 return false; 956 result->address = local->address + parent->address; 957 } else { 958 result->address = parent->address; 959 } 960 961 result->min_residency = max(local->min_residency, parent->min_residency); 962 result->wake_latency = local->wake_latency + parent->wake_latency; 963 result->enable_parent_state = parent->enable_parent_state; 964 result->entry_method = local->entry_method; 965 966 result->flags = parent->flags; 967 result->arch_flags = parent->arch_flags; 968 result->index = parent->index; 969 970 strlcpy(result->desc, local->desc, ACPI_CX_DESC_LEN); 971 strlcat(result->desc, "+", ACPI_CX_DESC_LEN); 972 strlcat(result->desc, parent->desc, ACPI_CX_DESC_LEN); 973 return true; 974 } 975 976 #define ACPI_LPI_STATE_FLAGS_ENABLED BIT(0) 977 978 static void stash_composite_state(struct acpi_lpi_states_array *curr_level, 979 struct acpi_lpi_state *t) 980 { 981 curr_level->composite_states[curr_level->composite_states_size++] = t; 982 } 983 984 static int flatten_lpi_states(struct acpi_processor *pr, 985 struct acpi_lpi_states_array *curr_level, 986 struct acpi_lpi_states_array *prev_level) 987 { 988 int i, j, state_count = curr_level->size; 989 struct acpi_lpi_state *p, *t = curr_level->entries; 990 991 curr_level->composite_states_size = 0; 992 for (j = 0; j < state_count; j++, t++) { 993 struct acpi_lpi_state *flpi; 994 995 if (!(t->flags & ACPI_LPI_STATE_FLAGS_ENABLED)) 996 continue; 997 998 if (flat_state_cnt >= ACPI_PROCESSOR_MAX_POWER) { 999 pr_warn("Limiting number of LPI states to max (%d)\n", 1000 ACPI_PROCESSOR_MAX_POWER); 1001 pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); 1002 break; 1003 } 1004 1005 flpi = &pr->power.lpi_states[flat_state_cnt]; 1006 1007 if (!prev_level) { /* leaf/processor node */ 1008 memcpy(flpi, t, sizeof(*t)); 1009 stash_composite_state(curr_level, flpi); 1010 flat_state_cnt++; 1011 continue; 1012 } 1013 1014 for (i = 0; i < prev_level->composite_states_size; i++) { 1015 p = prev_level->composite_states[i]; 1016 if (t->index <= p->enable_parent_state && 1017 combine_lpi_states(p, t, flpi)) { 1018 stash_composite_state(curr_level, flpi); 1019 flat_state_cnt++; 1020 flpi++; 1021 } 1022 } 1023 } 1024 1025 kfree(curr_level->entries); 1026 return 0; 1027 } 1028 1029 static int acpi_processor_get_lpi_info(struct acpi_processor *pr) 1030 { 1031 int ret, i; 1032 acpi_status status; 1033 acpi_handle handle = pr->handle, pr_ahandle; 1034 struct acpi_device *d = NULL; 1035 struct acpi_lpi_states_array info[2], *tmp, *prev, *curr; 1036 1037 if (!osc_pc_lpi_support_confirmed) 1038 return -EOPNOTSUPP; 1039 1040 if (!acpi_has_method(handle, "_LPI")) 1041 return -EINVAL; 1042 1043 flat_state_cnt = 0; 1044 prev = &info[0]; 1045 curr = &info[1]; 1046 handle = pr->handle; 1047 ret = acpi_processor_evaluate_lpi(handle, prev); 1048 if (ret) 1049 return ret; 1050 flatten_lpi_states(pr, prev, NULL); 1051 1052 status = acpi_get_parent(handle, &pr_ahandle); 1053 while (ACPI_SUCCESS(status)) { 1054 acpi_bus_get_device(pr_ahandle, &d); 1055 handle = pr_ahandle; 1056 1057 if (strcmp(acpi_device_hid(d), ACPI_PROCESSOR_CONTAINER_HID)) 1058 break; 1059 1060 /* can be optional ? */ 1061 if (!acpi_has_method(handle, "_LPI")) 1062 break; 1063 1064 ret = acpi_processor_evaluate_lpi(handle, curr); 1065 if (ret) 1066 break; 1067 1068 /* flatten all the LPI states in this level of hierarchy */ 1069 flatten_lpi_states(pr, curr, prev); 1070 1071 tmp = prev, prev = curr, curr = tmp; 1072 1073 status = acpi_get_parent(handle, &pr_ahandle); 1074 } 1075 1076 pr->power.count = flat_state_cnt; 1077 /* reset the index after flattening */ 1078 for (i = 0; i < pr->power.count; i++) 1079 pr->power.lpi_states[i].index = i; 1080 1081 /* Tell driver that _LPI is supported. */ 1082 pr->flags.has_lpi = 1; 1083 pr->flags.power = 1; 1084 1085 return 0; 1086 } 1087 1088 int __weak acpi_processor_ffh_lpi_probe(unsigned int cpu) 1089 { 1090 return -ENODEV; 1091 } 1092 1093 int __weak acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) 1094 { 1095 return -ENODEV; 1096 } 1097 1098 /** 1099 * acpi_idle_lpi_enter - enters an ACPI any LPI state 1100 * @dev: the target CPU 1101 * @drv: cpuidle driver containing cpuidle state info 1102 * @index: index of target state 1103 * 1104 * Return: 0 for success or negative value for error 1105 */ 1106 static int acpi_idle_lpi_enter(struct cpuidle_device *dev, 1107 struct cpuidle_driver *drv, int index) 1108 { 1109 struct acpi_processor *pr; 1110 struct acpi_lpi_state *lpi; 1111 1112 pr = __this_cpu_read(processors); 1113 1114 if (unlikely(!pr)) 1115 return -EINVAL; 1116 1117 lpi = &pr->power.lpi_states[index]; 1118 if (lpi->entry_method == ACPI_CSTATE_FFH) 1119 return acpi_processor_ffh_lpi_enter(lpi); 1120 1121 return -EINVAL; 1122 } 1123 1124 static int acpi_processor_setup_lpi_states(struct acpi_processor *pr) 1125 { 1126 int i; 1127 struct acpi_lpi_state *lpi; 1128 struct cpuidle_state *state; 1129 struct cpuidle_driver *drv = &acpi_idle_driver; 1130 1131 if (!pr->flags.has_lpi) 1132 return -EOPNOTSUPP; 1133 1134 for (i = 0; i < pr->power.count && i < CPUIDLE_STATE_MAX; i++) { 1135 lpi = &pr->power.lpi_states[i]; 1136 1137 state = &drv->states[i]; 1138 snprintf(state->name, CPUIDLE_NAME_LEN, "LPI-%d", i); 1139 strlcpy(state->desc, lpi->desc, CPUIDLE_DESC_LEN); 1140 state->exit_latency = lpi->wake_latency; 1141 state->target_residency = lpi->min_residency; 1142 if (lpi->arch_flags) 1143 state->flags |= CPUIDLE_FLAG_TIMER_STOP; 1144 state->enter = acpi_idle_lpi_enter; 1145 drv->safe_state_index = i; 1146 } 1147 1148 drv->state_count = i; 1149 1150 return 0; 1151 } 1152 1153 /** 1154 * acpi_processor_setup_cpuidle_states- prepares and configures cpuidle 1155 * global state data i.e. idle routines 1156 * 1157 * @pr: the ACPI processor 1158 */ 1159 static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr) 1160 { 1161 int i; 1162 struct cpuidle_driver *drv = &acpi_idle_driver; 1163 1164 if (!pr->flags.power_setup_done || !pr->flags.power) 1165 return -EINVAL; 1166 1167 drv->safe_state_index = -1; 1168 for (i = ACPI_IDLE_STATE_START; i < CPUIDLE_STATE_MAX; i++) { 1169 drv->states[i].name[0] = '\0'; 1170 drv->states[i].desc[0] = '\0'; 1171 } 1172 1173 if (pr->flags.has_lpi) 1174 return acpi_processor_setup_lpi_states(pr); 1175 1176 return acpi_processor_setup_cstates(pr); 1177 } 1178 1179 /** 1180 * acpi_processor_setup_cpuidle_dev - prepares and configures CPUIDLE 1181 * device i.e. per-cpu data 1182 * 1183 * @pr: the ACPI processor 1184 * @dev : the cpuidle device 1185 */ 1186 static int acpi_processor_setup_cpuidle_dev(struct acpi_processor *pr, 1187 struct cpuidle_device *dev) 1188 { 1189 if (!pr->flags.power_setup_done || !pr->flags.power || !dev) 1190 return -EINVAL; 1191 1192 dev->cpu = pr->id; 1193 if (pr->flags.has_lpi) 1194 return acpi_processor_ffh_lpi_probe(pr->id); 1195 1196 return acpi_processor_setup_cpuidle_cx(pr, dev); 1197 } 1198 1199 static int acpi_processor_get_power_info(struct acpi_processor *pr) 1200 { 1201 int ret; 1202 1203 ret = acpi_processor_get_lpi_info(pr); 1204 if (ret) 1205 ret = acpi_processor_get_cstate_info(pr); 1206 1207 return ret; 1208 } 1209 1210 int acpi_processor_hotplug(struct acpi_processor *pr) 1211 { 1212 int ret = 0; 1213 struct cpuidle_device *dev; 1214 1215 if (disabled_by_idle_boot_param()) 1216 return 0; 1217 1218 if (!pr->flags.power_setup_done) 1219 return -ENODEV; 1220 1221 dev = per_cpu(acpi_cpuidle_device, pr->id); 1222 cpuidle_pause_and_lock(); 1223 cpuidle_disable_device(dev); 1224 ret = acpi_processor_get_power_info(pr); 1225 if (!ret && pr->flags.power) { 1226 acpi_processor_setup_cpuidle_dev(pr, dev); 1227 ret = cpuidle_enable_device(dev); 1228 } 1229 cpuidle_resume_and_unlock(); 1230 1231 return ret; 1232 } 1233 1234 int acpi_processor_power_state_has_changed(struct acpi_processor *pr) 1235 { 1236 int cpu; 1237 struct acpi_processor *_pr; 1238 struct cpuidle_device *dev; 1239 1240 if (disabled_by_idle_boot_param()) 1241 return 0; 1242 1243 if (!pr->flags.power_setup_done) 1244 return -ENODEV; 1245 1246 /* 1247 * FIXME: Design the ACPI notification to make it once per 1248 * system instead of once per-cpu. This condition is a hack 1249 * to make the code that updates C-States be called once. 1250 */ 1251 1252 if (pr->id == 0 && cpuidle_get_driver() == &acpi_idle_driver) { 1253 1254 /* Protect against cpu-hotplug */ 1255 get_online_cpus(); 1256 cpuidle_pause_and_lock(); 1257 1258 /* Disable all cpuidle devices */ 1259 for_each_online_cpu(cpu) { 1260 _pr = per_cpu(processors, cpu); 1261 if (!_pr || !_pr->flags.power_setup_done) 1262 continue; 1263 dev = per_cpu(acpi_cpuidle_device, cpu); 1264 cpuidle_disable_device(dev); 1265 } 1266 1267 /* Populate Updated C-state information */ 1268 acpi_processor_get_power_info(pr); 1269 acpi_processor_setup_cpuidle_states(pr); 1270 1271 /* Enable all cpuidle devices */ 1272 for_each_online_cpu(cpu) { 1273 _pr = per_cpu(processors, cpu); 1274 if (!_pr || !_pr->flags.power_setup_done) 1275 continue; 1276 acpi_processor_get_power_info(_pr); 1277 if (_pr->flags.power) { 1278 dev = per_cpu(acpi_cpuidle_device, cpu); 1279 acpi_processor_setup_cpuidle_dev(_pr, dev); 1280 cpuidle_enable_device(dev); 1281 } 1282 } 1283 cpuidle_resume_and_unlock(); 1284 put_online_cpus(); 1285 } 1286 1287 return 0; 1288 } 1289 1290 static int acpi_processor_registered; 1291 1292 int acpi_processor_power_init(struct acpi_processor *pr) 1293 { 1294 int retval; 1295 struct cpuidle_device *dev; 1296 1297 if (disabled_by_idle_boot_param()) 1298 return 0; 1299 1300 acpi_processor_cstate_first_run_checks(); 1301 1302 if (!acpi_processor_get_power_info(pr)) 1303 pr->flags.power_setup_done = 1; 1304 1305 /* 1306 * Install the idle handler if processor power management is supported. 1307 * Note that we use previously set idle handler will be used on 1308 * platforms that only support C1. 1309 */ 1310 if (pr->flags.power) { 1311 /* Register acpi_idle_driver if not already registered */ 1312 if (!acpi_processor_registered) { 1313 acpi_processor_setup_cpuidle_states(pr); 1314 retval = cpuidle_register_driver(&acpi_idle_driver); 1315 if (retval) 1316 return retval; 1317 pr_debug("%s registered with cpuidle\n", 1318 acpi_idle_driver.name); 1319 } 1320 1321 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 1322 if (!dev) 1323 return -ENOMEM; 1324 per_cpu(acpi_cpuidle_device, pr->id) = dev; 1325 1326 acpi_processor_setup_cpuidle_dev(pr, dev); 1327 1328 /* Register per-cpu cpuidle_device. Cpuidle driver 1329 * must already be registered before registering device 1330 */ 1331 retval = cpuidle_register_device(dev); 1332 if (retval) { 1333 if (acpi_processor_registered == 0) 1334 cpuidle_unregister_driver(&acpi_idle_driver); 1335 return retval; 1336 } 1337 acpi_processor_registered++; 1338 } 1339 return 0; 1340 } 1341 1342 int acpi_processor_power_exit(struct acpi_processor *pr) 1343 { 1344 struct cpuidle_device *dev = per_cpu(acpi_cpuidle_device, pr->id); 1345 1346 if (disabled_by_idle_boot_param()) 1347 return 0; 1348 1349 if (pr->flags.power) { 1350 cpuidle_unregister_device(dev); 1351 acpi_processor_registered--; 1352 if (acpi_processor_registered == 0) 1353 cpuidle_unregister_driver(&acpi_idle_driver); 1354 } 1355 1356 pr->flags.power_setup_done = 0; 1357 return 0; 1358 } 1359