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/sort.h> 20 #include <linux/tick.h> 21 #include <linux/cpuidle.h> 22 #include <linux/cpu.h> 23 #include <linux/minmax.h> 24 #include <linux/perf_event.h> 25 #include <acpi/processor.h> 26 27 /* 28 * Include the apic definitions for x86 to have the APIC timer related defines 29 * available also for UP (on SMP it gets magically included via linux/smp.h). 30 * asm/acpi.h is not an option, as it would require more include magic. Also 31 * creating an empty asm-ia64/apic.h would just trade pest vs. cholera. 32 */ 33 #ifdef CONFIG_X86 34 #include <asm/apic.h> 35 #include <asm/cpu.h> 36 #endif 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, 0400); 42 static bool nocst __read_mostly; 43 module_param(nocst, bool, 0400); 44 static bool bm_check_disable __read_mostly; 45 module_param(bm_check_disable, bool, 0400); 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 bool lapic_timer_needs_broadcast(struct acpi_processor *pr, 165 struct acpi_processor_cx *cx) 166 { 167 return cx - pr->power.states >= pr->power.timer_broadcast_on_state; 168 } 169 170 #else 171 172 static void lapic_timer_check_state(int state, struct acpi_processor *pr, 173 struct acpi_processor_cx *cstate) { } 174 static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { } 175 176 static bool lapic_timer_needs_broadcast(struct acpi_processor *pr, 177 struct acpi_processor_cx *cx) 178 { 179 return false; 180 } 181 182 #endif 183 184 #if defined(CONFIG_X86) 185 static void tsc_check_state(int state) 186 { 187 switch (boot_cpu_data.x86_vendor) { 188 case X86_VENDOR_HYGON: 189 case X86_VENDOR_AMD: 190 case X86_VENDOR_INTEL: 191 case X86_VENDOR_CENTAUR: 192 case X86_VENDOR_ZHAOXIN: 193 /* 194 * AMD Fam10h TSC will tick in all 195 * C/P/S0/S1 states when this bit is set. 196 */ 197 if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) 198 return; 199 fallthrough; 200 default: 201 /* TSC could halt in idle, so notify users */ 202 if (state > ACPI_STATE_C1) 203 mark_tsc_unstable("TSC halts in idle"); 204 } 205 } 206 #else 207 static void tsc_check_state(int state) { return; } 208 #endif 209 210 static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) 211 { 212 213 if (!pr->pblk) 214 return -ENODEV; 215 216 /* if info is obtained from pblk/fadt, type equals state */ 217 pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; 218 pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; 219 220 #ifndef CONFIG_HOTPLUG_CPU 221 /* 222 * Check for P_LVL2_UP flag before entering C2 and above on 223 * an SMP system. 224 */ 225 if ((num_online_cpus() > 1) && 226 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) 227 return -ENODEV; 228 #endif 229 230 /* determine C2 and C3 address from pblk */ 231 pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; 232 pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; 233 234 /* determine latencies from FADT */ 235 pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.c2_latency; 236 pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.c3_latency; 237 238 /* 239 * FADT specified C2 latency must be less than or equal to 240 * 100 microseconds. 241 */ 242 if (acpi_gbl_FADT.c2_latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { 243 acpi_handle_debug(pr->handle, "C2 latency too large [%d]\n", 244 acpi_gbl_FADT.c2_latency); 245 /* invalidate C2 */ 246 pr->power.states[ACPI_STATE_C2].address = 0; 247 } 248 249 /* 250 * FADT supplied C3 latency must be less than or equal to 251 * 1000 microseconds. 252 */ 253 if (acpi_gbl_FADT.c3_latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { 254 acpi_handle_debug(pr->handle, "C3 latency too large [%d]\n", 255 acpi_gbl_FADT.c3_latency); 256 /* invalidate C3 */ 257 pr->power.states[ACPI_STATE_C3].address = 0; 258 } 259 260 acpi_handle_debug(pr->handle, "lvl2[0x%08x] lvl3[0x%08x]\n", 261 pr->power.states[ACPI_STATE_C2].address, 262 pr->power.states[ACPI_STATE_C3].address); 263 264 snprintf(pr->power.states[ACPI_STATE_C2].desc, 265 ACPI_CX_DESC_LEN, "ACPI P_LVL2 IOPORT 0x%x", 266 pr->power.states[ACPI_STATE_C2].address); 267 snprintf(pr->power.states[ACPI_STATE_C3].desc, 268 ACPI_CX_DESC_LEN, "ACPI P_LVL3 IOPORT 0x%x", 269 pr->power.states[ACPI_STATE_C3].address); 270 271 return 0; 272 } 273 274 static int acpi_processor_get_power_info_default(struct acpi_processor *pr) 275 { 276 if (!pr->power.states[ACPI_STATE_C1].valid) { 277 /* set the first C-State to C1 */ 278 /* all processors need to support C1 */ 279 pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; 280 pr->power.states[ACPI_STATE_C1].valid = 1; 281 pr->power.states[ACPI_STATE_C1].entry_method = ACPI_CSTATE_HALT; 282 283 snprintf(pr->power.states[ACPI_STATE_C1].desc, 284 ACPI_CX_DESC_LEN, "ACPI HLT"); 285 } 286 /* the C0 state only exists as a filler in our array */ 287 pr->power.states[ACPI_STATE_C0].valid = 1; 288 return 0; 289 } 290 291 static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) 292 { 293 int ret; 294 295 if (nocst) 296 return -ENODEV; 297 298 ret = acpi_processor_evaluate_cst(pr->handle, pr->id, &pr->power); 299 if (ret) 300 return ret; 301 302 if (!pr->power.count) 303 return -EFAULT; 304 305 pr->flags.has_cst = 1; 306 return 0; 307 } 308 309 static void acpi_processor_power_verify_c3(struct acpi_processor *pr, 310 struct acpi_processor_cx *cx) 311 { 312 static int bm_check_flag = -1; 313 static int bm_control_flag = -1; 314 315 316 if (!cx->address) 317 return; 318 319 /* 320 * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) 321 * DMA transfers are used by any ISA device to avoid livelock. 322 * Note that we could disable Type-F DMA (as recommended by 323 * the erratum), but this is known to disrupt certain ISA 324 * devices thus we take the conservative approach. 325 */ 326 else if (errata.piix4.fdma) { 327 acpi_handle_debug(pr->handle, 328 "C3 not supported on PIIX4 with Type-F DMA\n"); 329 return; 330 } 331 332 /* All the logic here assumes flags.bm_check is same across all CPUs */ 333 if (bm_check_flag == -1) { 334 /* Determine whether bm_check is needed based on CPU */ 335 acpi_processor_power_init_bm_check(&(pr->flags), pr->id); 336 bm_check_flag = pr->flags.bm_check; 337 bm_control_flag = pr->flags.bm_control; 338 } else { 339 pr->flags.bm_check = bm_check_flag; 340 pr->flags.bm_control = bm_control_flag; 341 } 342 343 if (pr->flags.bm_check) { 344 if (!pr->flags.bm_control) { 345 if (pr->flags.has_cst != 1) { 346 /* bus mastering control is necessary */ 347 acpi_handle_debug(pr->handle, 348 "C3 support requires BM control\n"); 349 return; 350 } else { 351 /* Here we enter C3 without bus mastering */ 352 acpi_handle_debug(pr->handle, 353 "C3 support without BM control\n"); 354 } 355 } 356 } else { 357 /* 358 * WBINVD should be set in fadt, for C3 state to be 359 * supported on when bm_check is not required. 360 */ 361 if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) { 362 acpi_handle_debug(pr->handle, 363 "Cache invalidation should work properly" 364 " for C3 to be enabled on SMP systems\n"); 365 return; 366 } 367 } 368 369 /* 370 * Otherwise we've met all of our C3 requirements. 371 * Normalize the C3 latency to expidite policy. Enable 372 * checking of bus mastering status (bm_check) so we can 373 * use this in our C3 policy 374 */ 375 cx->valid = 1; 376 377 /* 378 * On older chipsets, BM_RLD needs to be set 379 * in order for Bus Master activity to wake the 380 * system from C3. Newer chipsets handle DMA 381 * during C3 automatically and BM_RLD is a NOP. 382 * In either case, the proper way to 383 * handle BM_RLD is to set it and leave it set. 384 */ 385 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 1); 386 387 return; 388 } 389 390 static int acpi_cst_latency_cmp(const void *a, const void *b) 391 { 392 const struct acpi_processor_cx *x = a, *y = b; 393 394 if (!(x->valid && y->valid)) 395 return 0; 396 if (x->latency > y->latency) 397 return 1; 398 if (x->latency < y->latency) 399 return -1; 400 return 0; 401 } 402 static void acpi_cst_latency_swap(void *a, void *b, int n) 403 { 404 struct acpi_processor_cx *x = a, *y = b; 405 406 if (!(x->valid && y->valid)) 407 return; 408 swap(x->latency, y->latency); 409 } 410 411 static int acpi_processor_power_verify(struct acpi_processor *pr) 412 { 413 unsigned int i; 414 unsigned int working = 0; 415 unsigned int last_latency = 0; 416 unsigned int last_type = 0; 417 bool buggy_latency = false; 418 419 pr->power.timer_broadcast_on_state = INT_MAX; 420 421 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 422 struct acpi_processor_cx *cx = &pr->power.states[i]; 423 424 switch (cx->type) { 425 case ACPI_STATE_C1: 426 cx->valid = 1; 427 break; 428 429 case ACPI_STATE_C2: 430 if (!cx->address) 431 break; 432 cx->valid = 1; 433 break; 434 435 case ACPI_STATE_C3: 436 acpi_processor_power_verify_c3(pr, cx); 437 break; 438 } 439 if (!cx->valid) 440 continue; 441 if (cx->type >= last_type && cx->latency < last_latency) 442 buggy_latency = true; 443 last_latency = cx->latency; 444 last_type = cx->type; 445 446 lapic_timer_check_state(i, pr, cx); 447 tsc_check_state(cx->type); 448 working++; 449 } 450 451 if (buggy_latency) { 452 pr_notice("FW issue: working around C-state latencies out of order\n"); 453 sort(&pr->power.states[1], max_cstate, 454 sizeof(struct acpi_processor_cx), 455 acpi_cst_latency_cmp, 456 acpi_cst_latency_swap); 457 } 458 459 lapic_timer_propagate_broadcast(pr); 460 461 return (working); 462 } 463 464 static int acpi_processor_get_cstate_info(struct acpi_processor *pr) 465 { 466 unsigned int i; 467 int result; 468 469 470 /* NOTE: the idle thread may not be running while calling 471 * this function */ 472 473 /* Zero initialize all the C-states info. */ 474 memset(pr->power.states, 0, sizeof(pr->power.states)); 475 476 result = acpi_processor_get_power_info_cst(pr); 477 if (result == -ENODEV) 478 result = acpi_processor_get_power_info_fadt(pr); 479 480 if (result) 481 return result; 482 483 acpi_processor_get_power_info_default(pr); 484 485 pr->power.count = acpi_processor_power_verify(pr); 486 487 /* 488 * if one state of type C2 or C3 is available, mark this 489 * CPU as being "idle manageable" 490 */ 491 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { 492 if (pr->power.states[i].valid) { 493 pr->power.count = i; 494 pr->flags.power = 1; 495 } 496 } 497 498 return 0; 499 } 500 501 /** 502 * acpi_idle_bm_check - checks if bus master activity was detected 503 */ 504 static int acpi_idle_bm_check(void) 505 { 506 u32 bm_status = 0; 507 508 if (bm_check_disable) 509 return 0; 510 511 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); 512 if (bm_status) 513 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1); 514 /* 515 * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect 516 * the true state of bus mastering activity; forcing us to 517 * manually check the BMIDEA bit of each IDE channel. 518 */ 519 else if (errata.piix4.bmisx) { 520 if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) 521 || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) 522 bm_status = 1; 523 } 524 return bm_status; 525 } 526 527 static void wait_for_freeze(void) 528 { 529 #ifdef CONFIG_X86 530 /* No delay is needed if we are in guest */ 531 if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) 532 return; 533 #endif 534 /* Dummy wait op - must do something useless after P_LVL2 read 535 because chipsets cannot guarantee that STPCLK# signal 536 gets asserted in time to freeze execution properly. */ 537 inl(acpi_gbl_FADT.xpm_timer_block.address); 538 } 539 540 /** 541 * acpi_idle_do_entry - enter idle state using the appropriate method 542 * @cx: cstate data 543 * 544 * Caller disables interrupt before call and enables interrupt after return. 545 */ 546 static void __cpuidle acpi_idle_do_entry(struct acpi_processor_cx *cx) 547 { 548 perf_lopwr_cb(true); 549 550 if (cx->entry_method == ACPI_CSTATE_FFH) { 551 /* Call into architectural FFH based C-state */ 552 acpi_processor_ffh_cstate_enter(cx); 553 } else if (cx->entry_method == ACPI_CSTATE_HALT) { 554 acpi_safe_halt(); 555 } else { 556 /* IO port based C-state */ 557 inb(cx->address); 558 wait_for_freeze(); 559 } 560 561 perf_lopwr_cb(false); 562 } 563 564 /** 565 * acpi_idle_play_dead - enters an ACPI state for long-term idle (i.e. off-lining) 566 * @dev: the target CPU 567 * @index: the index of suggested state 568 */ 569 static int acpi_idle_play_dead(struct cpuidle_device *dev, int index) 570 { 571 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); 572 573 ACPI_FLUSH_CPU_CACHE(); 574 575 while (1) { 576 577 if (cx->entry_method == ACPI_CSTATE_HALT) 578 safe_halt(); 579 else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) { 580 inb(cx->address); 581 wait_for_freeze(); 582 } else 583 return -ENODEV; 584 585 #if defined(CONFIG_X86) && defined(CONFIG_HOTPLUG_CPU) 586 cond_wakeup_cpu0(); 587 #endif 588 } 589 590 /* Never reached */ 591 return 0; 592 } 593 594 static bool acpi_idle_fallback_to_c1(struct acpi_processor *pr) 595 { 596 return IS_ENABLED(CONFIG_HOTPLUG_CPU) && !pr->flags.has_cst && 597 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED); 598 } 599 600 static int c3_cpu_count; 601 static DEFINE_RAW_SPINLOCK(c3_lock); 602 603 /** 604 * acpi_idle_enter_bm - enters C3 with proper BM handling 605 * @drv: cpuidle driver 606 * @pr: Target processor 607 * @cx: Target state context 608 * @index: index of target state 609 */ 610 static int acpi_idle_enter_bm(struct cpuidle_driver *drv, 611 struct acpi_processor *pr, 612 struct acpi_processor_cx *cx, 613 int index) 614 { 615 static struct acpi_processor_cx safe_cx = { 616 .entry_method = ACPI_CSTATE_HALT, 617 }; 618 619 /* 620 * disable bus master 621 * bm_check implies we need ARB_DIS 622 * bm_control implies whether we can do ARB_DIS 623 * 624 * That leaves a case where bm_check is set and bm_control is not set. 625 * In that case we cannot do much, we enter C3 without doing anything. 626 */ 627 bool dis_bm = pr->flags.bm_control; 628 629 /* If we can skip BM, demote to a safe state. */ 630 if (!cx->bm_sts_skip && acpi_idle_bm_check()) { 631 dis_bm = false; 632 index = drv->safe_state_index; 633 if (index >= 0) { 634 cx = this_cpu_read(acpi_cstate[index]); 635 } else { 636 cx = &safe_cx; 637 index = -EBUSY; 638 } 639 } 640 641 if (dis_bm) { 642 raw_spin_lock(&c3_lock); 643 c3_cpu_count++; 644 /* Disable bus master arbitration when all CPUs are in C3 */ 645 if (c3_cpu_count == num_online_cpus()) 646 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1); 647 raw_spin_unlock(&c3_lock); 648 } 649 650 rcu_idle_enter(); 651 652 acpi_idle_do_entry(cx); 653 654 rcu_idle_exit(); 655 656 /* Re-enable bus master arbitration */ 657 if (dis_bm) { 658 raw_spin_lock(&c3_lock); 659 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); 660 c3_cpu_count--; 661 raw_spin_unlock(&c3_lock); 662 } 663 664 return index; 665 } 666 667 static int acpi_idle_enter(struct cpuidle_device *dev, 668 struct cpuidle_driver *drv, int index) 669 { 670 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); 671 struct acpi_processor *pr; 672 673 pr = __this_cpu_read(processors); 674 if (unlikely(!pr)) 675 return -EINVAL; 676 677 if (cx->type != ACPI_STATE_C1) { 678 if (cx->type == ACPI_STATE_C3 && pr->flags.bm_check) 679 return acpi_idle_enter_bm(drv, pr, cx, index); 680 681 /* C2 to C1 demotion. */ 682 if (acpi_idle_fallback_to_c1(pr) && num_online_cpus() > 1) { 683 index = ACPI_IDLE_STATE_START; 684 cx = per_cpu(acpi_cstate[index], dev->cpu); 685 } 686 } 687 688 if (cx->type == ACPI_STATE_C3) 689 ACPI_FLUSH_CPU_CACHE(); 690 691 acpi_idle_do_entry(cx); 692 693 return index; 694 } 695 696 static int acpi_idle_enter_s2idle(struct cpuidle_device *dev, 697 struct cpuidle_driver *drv, int index) 698 { 699 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); 700 701 if (cx->type == ACPI_STATE_C3) { 702 struct acpi_processor *pr = __this_cpu_read(processors); 703 704 if (unlikely(!pr)) 705 return 0; 706 707 if (pr->flags.bm_check) { 708 u8 bm_sts_skip = cx->bm_sts_skip; 709 710 /* Don't check BM_STS, do an unconditional ARB_DIS for S2IDLE */ 711 cx->bm_sts_skip = 1; 712 acpi_idle_enter_bm(drv, pr, cx, index); 713 cx->bm_sts_skip = bm_sts_skip; 714 715 return 0; 716 } else { 717 ACPI_FLUSH_CPU_CACHE(); 718 } 719 } 720 acpi_idle_do_entry(cx); 721 722 return 0; 723 } 724 725 static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr, 726 struct cpuidle_device *dev) 727 { 728 int i, count = ACPI_IDLE_STATE_START; 729 struct acpi_processor_cx *cx; 730 struct cpuidle_state *state; 731 732 if (max_cstate == 0) 733 max_cstate = 1; 734 735 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 736 state = &acpi_idle_driver.states[count]; 737 cx = &pr->power.states[i]; 738 739 if (!cx->valid) 740 continue; 741 742 per_cpu(acpi_cstate[count], dev->cpu) = cx; 743 744 if (lapic_timer_needs_broadcast(pr, cx)) 745 state->flags |= CPUIDLE_FLAG_TIMER_STOP; 746 747 if (cx->type == ACPI_STATE_C3) { 748 state->flags |= CPUIDLE_FLAG_TLB_FLUSHED; 749 if (pr->flags.bm_check) 750 state->flags |= CPUIDLE_FLAG_RCU_IDLE; 751 } 752 753 count++; 754 if (count == CPUIDLE_STATE_MAX) 755 break; 756 } 757 758 if (!count) 759 return -EINVAL; 760 761 return 0; 762 } 763 764 static int acpi_processor_setup_cstates(struct acpi_processor *pr) 765 { 766 int i, count; 767 struct acpi_processor_cx *cx; 768 struct cpuidle_state *state; 769 struct cpuidle_driver *drv = &acpi_idle_driver; 770 771 if (max_cstate == 0) 772 max_cstate = 1; 773 774 if (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX)) { 775 cpuidle_poll_state_init(drv); 776 count = 1; 777 } else { 778 count = 0; 779 } 780 781 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { 782 cx = &pr->power.states[i]; 783 784 if (!cx->valid) 785 continue; 786 787 state = &drv->states[count]; 788 snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i); 789 strlcpy(state->desc, cx->desc, CPUIDLE_DESC_LEN); 790 state->exit_latency = cx->latency; 791 state->target_residency = cx->latency * latency_factor; 792 state->enter = acpi_idle_enter; 793 794 state->flags = 0; 795 if (cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2 || 796 cx->type == ACPI_STATE_C3) { 797 state->enter_dead = acpi_idle_play_dead; 798 if (cx->type != ACPI_STATE_C3) 799 drv->safe_state_index = count; 800 } 801 /* 802 * Halt-induced C1 is not good for ->enter_s2idle, because it 803 * re-enables interrupts on exit. Moreover, C1 is generally not 804 * particularly interesting from the suspend-to-idle angle, so 805 * avoid C1 and the situations in which we may need to fall back 806 * to it altogether. 807 */ 808 if (cx->type != ACPI_STATE_C1 && !acpi_idle_fallback_to_c1(pr)) 809 state->enter_s2idle = acpi_idle_enter_s2idle; 810 811 count++; 812 if (count == CPUIDLE_STATE_MAX) 813 break; 814 } 815 816 drv->state_count = count; 817 818 if (!count) 819 return -EINVAL; 820 821 return 0; 822 } 823 824 static inline void acpi_processor_cstate_first_run_checks(void) 825 { 826 static int first_run; 827 828 if (first_run) 829 return; 830 dmi_check_system(processor_power_dmi_table); 831 max_cstate = acpi_processor_cstate_check(max_cstate); 832 if (max_cstate < ACPI_C_STATES_MAX) 833 pr_notice("processor limited to max C-state %d\n", max_cstate); 834 835 first_run++; 836 837 if (nocst) 838 return; 839 840 acpi_processor_claim_cst_control(); 841 } 842 #else 843 844 static inline int disabled_by_idle_boot_param(void) { return 0; } 845 static inline void acpi_processor_cstate_first_run_checks(void) { } 846 static int acpi_processor_get_cstate_info(struct acpi_processor *pr) 847 { 848 return -ENODEV; 849 } 850 851 static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr, 852 struct cpuidle_device *dev) 853 { 854 return -EINVAL; 855 } 856 857 static int acpi_processor_setup_cstates(struct acpi_processor *pr) 858 { 859 return -EINVAL; 860 } 861 862 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */ 863 864 struct acpi_lpi_states_array { 865 unsigned int size; 866 unsigned int composite_states_size; 867 struct acpi_lpi_state *entries; 868 struct acpi_lpi_state *composite_states[ACPI_PROCESSOR_MAX_POWER]; 869 }; 870 871 static int obj_get_integer(union acpi_object *obj, u32 *value) 872 { 873 if (obj->type != ACPI_TYPE_INTEGER) 874 return -EINVAL; 875 876 *value = obj->integer.value; 877 return 0; 878 } 879 880 static int acpi_processor_evaluate_lpi(acpi_handle handle, 881 struct acpi_lpi_states_array *info) 882 { 883 acpi_status status; 884 int ret = 0; 885 int pkg_count, state_idx = 1, loop; 886 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 887 union acpi_object *lpi_data; 888 struct acpi_lpi_state *lpi_state; 889 890 status = acpi_evaluate_object(handle, "_LPI", NULL, &buffer); 891 if (ACPI_FAILURE(status)) { 892 acpi_handle_debug(handle, "No _LPI, giving up\n"); 893 return -ENODEV; 894 } 895 896 lpi_data = buffer.pointer; 897 898 /* There must be at least 4 elements = 3 elements + 1 package */ 899 if (!lpi_data || lpi_data->type != ACPI_TYPE_PACKAGE || 900 lpi_data->package.count < 4) { 901 pr_debug("not enough elements in _LPI\n"); 902 ret = -ENODATA; 903 goto end; 904 } 905 906 pkg_count = lpi_data->package.elements[2].integer.value; 907 908 /* Validate number of power states. */ 909 if (pkg_count < 1 || pkg_count != lpi_data->package.count - 3) { 910 pr_debug("count given by _LPI is not valid\n"); 911 ret = -ENODATA; 912 goto end; 913 } 914 915 lpi_state = kcalloc(pkg_count, sizeof(*lpi_state), GFP_KERNEL); 916 if (!lpi_state) { 917 ret = -ENOMEM; 918 goto end; 919 } 920 921 info->size = pkg_count; 922 info->entries = lpi_state; 923 924 /* LPI States start at index 3 */ 925 for (loop = 3; state_idx <= pkg_count; loop++, state_idx++, lpi_state++) { 926 union acpi_object *element, *pkg_elem, *obj; 927 928 element = &lpi_data->package.elements[loop]; 929 if (element->type != ACPI_TYPE_PACKAGE || element->package.count < 7) 930 continue; 931 932 pkg_elem = element->package.elements; 933 934 obj = pkg_elem + 6; 935 if (obj->type == ACPI_TYPE_BUFFER) { 936 struct acpi_power_register *reg; 937 938 reg = (struct acpi_power_register *)obj->buffer.pointer; 939 if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && 940 reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) 941 continue; 942 943 lpi_state->address = reg->address; 944 lpi_state->entry_method = 945 reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE ? 946 ACPI_CSTATE_FFH : ACPI_CSTATE_SYSTEMIO; 947 } else if (obj->type == ACPI_TYPE_INTEGER) { 948 lpi_state->entry_method = ACPI_CSTATE_INTEGER; 949 lpi_state->address = obj->integer.value; 950 } else { 951 continue; 952 } 953 954 /* elements[7,8] skipped for now i.e. Residency/Usage counter*/ 955 956 obj = pkg_elem + 9; 957 if (obj->type == ACPI_TYPE_STRING) 958 strlcpy(lpi_state->desc, obj->string.pointer, 959 ACPI_CX_DESC_LEN); 960 961 lpi_state->index = state_idx; 962 if (obj_get_integer(pkg_elem + 0, &lpi_state->min_residency)) { 963 pr_debug("No min. residency found, assuming 10 us\n"); 964 lpi_state->min_residency = 10; 965 } 966 967 if (obj_get_integer(pkg_elem + 1, &lpi_state->wake_latency)) { 968 pr_debug("No wakeup residency found, assuming 10 us\n"); 969 lpi_state->wake_latency = 10; 970 } 971 972 if (obj_get_integer(pkg_elem + 2, &lpi_state->flags)) 973 lpi_state->flags = 0; 974 975 if (obj_get_integer(pkg_elem + 3, &lpi_state->arch_flags)) 976 lpi_state->arch_flags = 0; 977 978 if (obj_get_integer(pkg_elem + 4, &lpi_state->res_cnt_freq)) 979 lpi_state->res_cnt_freq = 1; 980 981 if (obj_get_integer(pkg_elem + 5, &lpi_state->enable_parent_state)) 982 lpi_state->enable_parent_state = 0; 983 } 984 985 acpi_handle_debug(handle, "Found %d power states\n", state_idx); 986 end: 987 kfree(buffer.pointer); 988 return ret; 989 } 990 991 /* 992 * flat_state_cnt - the number of composite LPI states after the process of flattening 993 */ 994 static int flat_state_cnt; 995 996 /** 997 * combine_lpi_states - combine local and parent LPI states to form a composite LPI state 998 * 999 * @local: local LPI state 1000 * @parent: parent LPI state 1001 * @result: composite LPI state 1002 */ 1003 static bool combine_lpi_states(struct acpi_lpi_state *local, 1004 struct acpi_lpi_state *parent, 1005 struct acpi_lpi_state *result) 1006 { 1007 if (parent->entry_method == ACPI_CSTATE_INTEGER) { 1008 if (!parent->address) /* 0 means autopromotable */ 1009 return false; 1010 result->address = local->address + parent->address; 1011 } else { 1012 result->address = parent->address; 1013 } 1014 1015 result->min_residency = max(local->min_residency, parent->min_residency); 1016 result->wake_latency = local->wake_latency + parent->wake_latency; 1017 result->enable_parent_state = parent->enable_parent_state; 1018 result->entry_method = local->entry_method; 1019 1020 result->flags = parent->flags; 1021 result->arch_flags = parent->arch_flags; 1022 result->index = parent->index; 1023 1024 strlcpy(result->desc, local->desc, ACPI_CX_DESC_LEN); 1025 strlcat(result->desc, "+", ACPI_CX_DESC_LEN); 1026 strlcat(result->desc, parent->desc, ACPI_CX_DESC_LEN); 1027 return true; 1028 } 1029 1030 #define ACPI_LPI_STATE_FLAGS_ENABLED BIT(0) 1031 1032 static void stash_composite_state(struct acpi_lpi_states_array *curr_level, 1033 struct acpi_lpi_state *t) 1034 { 1035 curr_level->composite_states[curr_level->composite_states_size++] = t; 1036 } 1037 1038 static int flatten_lpi_states(struct acpi_processor *pr, 1039 struct acpi_lpi_states_array *curr_level, 1040 struct acpi_lpi_states_array *prev_level) 1041 { 1042 int i, j, state_count = curr_level->size; 1043 struct acpi_lpi_state *p, *t = curr_level->entries; 1044 1045 curr_level->composite_states_size = 0; 1046 for (j = 0; j < state_count; j++, t++) { 1047 struct acpi_lpi_state *flpi; 1048 1049 if (!(t->flags & ACPI_LPI_STATE_FLAGS_ENABLED)) 1050 continue; 1051 1052 if (flat_state_cnt >= ACPI_PROCESSOR_MAX_POWER) { 1053 pr_warn("Limiting number of LPI states to max (%d)\n", 1054 ACPI_PROCESSOR_MAX_POWER); 1055 pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); 1056 break; 1057 } 1058 1059 flpi = &pr->power.lpi_states[flat_state_cnt]; 1060 1061 if (!prev_level) { /* leaf/processor node */ 1062 memcpy(flpi, t, sizeof(*t)); 1063 stash_composite_state(curr_level, flpi); 1064 flat_state_cnt++; 1065 continue; 1066 } 1067 1068 for (i = 0; i < prev_level->composite_states_size; i++) { 1069 p = prev_level->composite_states[i]; 1070 if (t->index <= p->enable_parent_state && 1071 combine_lpi_states(p, t, flpi)) { 1072 stash_composite_state(curr_level, flpi); 1073 flat_state_cnt++; 1074 flpi++; 1075 } 1076 } 1077 } 1078 1079 kfree(curr_level->entries); 1080 return 0; 1081 } 1082 1083 int __weak acpi_processor_ffh_lpi_probe(unsigned int cpu) 1084 { 1085 return -EOPNOTSUPP; 1086 } 1087 1088 static int acpi_processor_get_lpi_info(struct acpi_processor *pr) 1089 { 1090 int ret, i; 1091 acpi_status status; 1092 acpi_handle handle = pr->handle, pr_ahandle; 1093 struct acpi_device *d = NULL; 1094 struct acpi_lpi_states_array info[2], *tmp, *prev, *curr; 1095 1096 /* make sure our architecture has support */ 1097 ret = acpi_processor_ffh_lpi_probe(pr->id); 1098 if (ret == -EOPNOTSUPP) 1099 return ret; 1100 1101 if (!osc_pc_lpi_support_confirmed) 1102 return -EOPNOTSUPP; 1103 1104 if (!acpi_has_method(handle, "_LPI")) 1105 return -EINVAL; 1106 1107 flat_state_cnt = 0; 1108 prev = &info[0]; 1109 curr = &info[1]; 1110 handle = pr->handle; 1111 ret = acpi_processor_evaluate_lpi(handle, prev); 1112 if (ret) 1113 return ret; 1114 flatten_lpi_states(pr, prev, NULL); 1115 1116 status = acpi_get_parent(handle, &pr_ahandle); 1117 while (ACPI_SUCCESS(status)) { 1118 d = acpi_fetch_acpi_dev(pr_ahandle); 1119 handle = pr_ahandle; 1120 1121 if (strcmp(acpi_device_hid(d), ACPI_PROCESSOR_CONTAINER_HID)) 1122 break; 1123 1124 /* can be optional ? */ 1125 if (!acpi_has_method(handle, "_LPI")) 1126 break; 1127 1128 ret = acpi_processor_evaluate_lpi(handle, curr); 1129 if (ret) 1130 break; 1131 1132 /* flatten all the LPI states in this level of hierarchy */ 1133 flatten_lpi_states(pr, curr, prev); 1134 1135 tmp = prev, prev = curr, curr = tmp; 1136 1137 status = acpi_get_parent(handle, &pr_ahandle); 1138 } 1139 1140 pr->power.count = flat_state_cnt; 1141 /* reset the index after flattening */ 1142 for (i = 0; i < pr->power.count; i++) 1143 pr->power.lpi_states[i].index = i; 1144 1145 /* Tell driver that _LPI is supported. */ 1146 pr->flags.has_lpi = 1; 1147 pr->flags.power = 1; 1148 1149 return 0; 1150 } 1151 1152 int __weak acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) 1153 { 1154 return -ENODEV; 1155 } 1156 1157 /** 1158 * acpi_idle_lpi_enter - enters an ACPI any LPI state 1159 * @dev: the target CPU 1160 * @drv: cpuidle driver containing cpuidle state info 1161 * @index: index of target state 1162 * 1163 * Return: 0 for success or negative value for error 1164 */ 1165 static int acpi_idle_lpi_enter(struct cpuidle_device *dev, 1166 struct cpuidle_driver *drv, int index) 1167 { 1168 struct acpi_processor *pr; 1169 struct acpi_lpi_state *lpi; 1170 1171 pr = __this_cpu_read(processors); 1172 1173 if (unlikely(!pr)) 1174 return -EINVAL; 1175 1176 lpi = &pr->power.lpi_states[index]; 1177 if (lpi->entry_method == ACPI_CSTATE_FFH) 1178 return acpi_processor_ffh_lpi_enter(lpi); 1179 1180 return -EINVAL; 1181 } 1182 1183 static int acpi_processor_setup_lpi_states(struct acpi_processor *pr) 1184 { 1185 int i; 1186 struct acpi_lpi_state *lpi; 1187 struct cpuidle_state *state; 1188 struct cpuidle_driver *drv = &acpi_idle_driver; 1189 1190 if (!pr->flags.has_lpi) 1191 return -EOPNOTSUPP; 1192 1193 for (i = 0; i < pr->power.count && i < CPUIDLE_STATE_MAX; i++) { 1194 lpi = &pr->power.lpi_states[i]; 1195 1196 state = &drv->states[i]; 1197 snprintf(state->name, CPUIDLE_NAME_LEN, "LPI-%d", i); 1198 strlcpy(state->desc, lpi->desc, CPUIDLE_DESC_LEN); 1199 state->exit_latency = lpi->wake_latency; 1200 state->target_residency = lpi->min_residency; 1201 if (lpi->arch_flags) 1202 state->flags |= CPUIDLE_FLAG_TIMER_STOP; 1203 state->enter = acpi_idle_lpi_enter; 1204 drv->safe_state_index = i; 1205 } 1206 1207 drv->state_count = i; 1208 1209 return 0; 1210 } 1211 1212 /** 1213 * acpi_processor_setup_cpuidle_states- prepares and configures cpuidle 1214 * global state data i.e. idle routines 1215 * 1216 * @pr: the ACPI processor 1217 */ 1218 static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr) 1219 { 1220 int i; 1221 struct cpuidle_driver *drv = &acpi_idle_driver; 1222 1223 if (!pr->flags.power_setup_done || !pr->flags.power) 1224 return -EINVAL; 1225 1226 drv->safe_state_index = -1; 1227 for (i = ACPI_IDLE_STATE_START; i < CPUIDLE_STATE_MAX; i++) { 1228 drv->states[i].name[0] = '\0'; 1229 drv->states[i].desc[0] = '\0'; 1230 } 1231 1232 if (pr->flags.has_lpi) 1233 return acpi_processor_setup_lpi_states(pr); 1234 1235 return acpi_processor_setup_cstates(pr); 1236 } 1237 1238 /** 1239 * acpi_processor_setup_cpuidle_dev - prepares and configures CPUIDLE 1240 * device i.e. per-cpu data 1241 * 1242 * @pr: the ACPI processor 1243 * @dev : the cpuidle device 1244 */ 1245 static int acpi_processor_setup_cpuidle_dev(struct acpi_processor *pr, 1246 struct cpuidle_device *dev) 1247 { 1248 if (!pr->flags.power_setup_done || !pr->flags.power || !dev) 1249 return -EINVAL; 1250 1251 dev->cpu = pr->id; 1252 if (pr->flags.has_lpi) 1253 return acpi_processor_ffh_lpi_probe(pr->id); 1254 1255 return acpi_processor_setup_cpuidle_cx(pr, dev); 1256 } 1257 1258 static int acpi_processor_get_power_info(struct acpi_processor *pr) 1259 { 1260 int ret; 1261 1262 ret = acpi_processor_get_lpi_info(pr); 1263 if (ret) 1264 ret = acpi_processor_get_cstate_info(pr); 1265 1266 return ret; 1267 } 1268 1269 int acpi_processor_hotplug(struct acpi_processor *pr) 1270 { 1271 int ret = 0; 1272 struct cpuidle_device *dev; 1273 1274 if (disabled_by_idle_boot_param()) 1275 return 0; 1276 1277 if (!pr->flags.power_setup_done) 1278 return -ENODEV; 1279 1280 dev = per_cpu(acpi_cpuidle_device, pr->id); 1281 cpuidle_pause_and_lock(); 1282 cpuidle_disable_device(dev); 1283 ret = acpi_processor_get_power_info(pr); 1284 if (!ret && pr->flags.power) { 1285 acpi_processor_setup_cpuidle_dev(pr, dev); 1286 ret = cpuidle_enable_device(dev); 1287 } 1288 cpuidle_resume_and_unlock(); 1289 1290 return ret; 1291 } 1292 1293 int acpi_processor_power_state_has_changed(struct acpi_processor *pr) 1294 { 1295 int cpu; 1296 struct acpi_processor *_pr; 1297 struct cpuidle_device *dev; 1298 1299 if (disabled_by_idle_boot_param()) 1300 return 0; 1301 1302 if (!pr->flags.power_setup_done) 1303 return -ENODEV; 1304 1305 /* 1306 * FIXME: Design the ACPI notification to make it once per 1307 * system instead of once per-cpu. This condition is a hack 1308 * to make the code that updates C-States be called once. 1309 */ 1310 1311 if (pr->id == 0 && cpuidle_get_driver() == &acpi_idle_driver) { 1312 1313 /* Protect against cpu-hotplug */ 1314 cpus_read_lock(); 1315 cpuidle_pause_and_lock(); 1316 1317 /* Disable all cpuidle devices */ 1318 for_each_online_cpu(cpu) { 1319 _pr = per_cpu(processors, cpu); 1320 if (!_pr || !_pr->flags.power_setup_done) 1321 continue; 1322 dev = per_cpu(acpi_cpuidle_device, cpu); 1323 cpuidle_disable_device(dev); 1324 } 1325 1326 /* Populate Updated C-state information */ 1327 acpi_processor_get_power_info(pr); 1328 acpi_processor_setup_cpuidle_states(pr); 1329 1330 /* Enable all cpuidle devices */ 1331 for_each_online_cpu(cpu) { 1332 _pr = per_cpu(processors, cpu); 1333 if (!_pr || !_pr->flags.power_setup_done) 1334 continue; 1335 acpi_processor_get_power_info(_pr); 1336 if (_pr->flags.power) { 1337 dev = per_cpu(acpi_cpuidle_device, cpu); 1338 acpi_processor_setup_cpuidle_dev(_pr, dev); 1339 cpuidle_enable_device(dev); 1340 } 1341 } 1342 cpuidle_resume_and_unlock(); 1343 cpus_read_unlock(); 1344 } 1345 1346 return 0; 1347 } 1348 1349 static int acpi_processor_registered; 1350 1351 int acpi_processor_power_init(struct acpi_processor *pr) 1352 { 1353 int retval; 1354 struct cpuidle_device *dev; 1355 1356 if (disabled_by_idle_boot_param()) 1357 return 0; 1358 1359 acpi_processor_cstate_first_run_checks(); 1360 1361 if (!acpi_processor_get_power_info(pr)) 1362 pr->flags.power_setup_done = 1; 1363 1364 /* 1365 * Install the idle handler if processor power management is supported. 1366 * Note that we use previously set idle handler will be used on 1367 * platforms that only support C1. 1368 */ 1369 if (pr->flags.power) { 1370 /* Register acpi_idle_driver if not already registered */ 1371 if (!acpi_processor_registered) { 1372 acpi_processor_setup_cpuidle_states(pr); 1373 retval = cpuidle_register_driver(&acpi_idle_driver); 1374 if (retval) 1375 return retval; 1376 pr_debug("%s registered with cpuidle\n", 1377 acpi_idle_driver.name); 1378 } 1379 1380 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 1381 if (!dev) 1382 return -ENOMEM; 1383 per_cpu(acpi_cpuidle_device, pr->id) = dev; 1384 1385 acpi_processor_setup_cpuidle_dev(pr, dev); 1386 1387 /* Register per-cpu cpuidle_device. Cpuidle driver 1388 * must already be registered before registering device 1389 */ 1390 retval = cpuidle_register_device(dev); 1391 if (retval) { 1392 if (acpi_processor_registered == 0) 1393 cpuidle_unregister_driver(&acpi_idle_driver); 1394 return retval; 1395 } 1396 acpi_processor_registered++; 1397 } 1398 return 0; 1399 } 1400 1401 int acpi_processor_power_exit(struct acpi_processor *pr) 1402 { 1403 struct cpuidle_device *dev = per_cpu(acpi_cpuidle_device, pr->id); 1404 1405 if (disabled_by_idle_boot_param()) 1406 return 0; 1407 1408 if (pr->flags.power) { 1409 cpuidle_unregister_device(dev); 1410 acpi_processor_registered--; 1411 if (acpi_processor_registered == 0) 1412 cpuidle_unregister_driver(&acpi_idle_driver); 1413 } 1414 1415 pr->flags.power_setup_done = 0; 1416 return 0; 1417 } 1418