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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * processor_idle - idle state submodule to the ACPI processor driver4 *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 support10 * Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>11 * - Added support for C3 on SMP12 */13#define pr_fmt(fmt) "ACPI: " fmt14 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 <linux/minmax.h>23#include <linux/perf_event.h>24#include <acpi/processor.h>25#include <linux/context_tracking.h>26 27/*28 * Include the apic definitions for x86 to have the APIC timer related defines29 * 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. Also31 * creating an empty asm-ia64/apic.h would just trade pest vs. cholera.32 */33#ifdef CONFIG_X8634#include <asm/apic.h>35#include <asm/cpu.h>36#endif37 38#define ACPI_IDLE_STATE_START (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX) ? 1 : 0)39 40static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER;41module_param(max_cstate, uint, 0400);42static bool nocst __read_mostly;43module_param(nocst, bool, 0400);44static bool bm_check_disable __read_mostly;45module_param(bm_check_disable, bool, 0400);46 47static unsigned int latency_factor __read_mostly = 2;48module_param(latency_factor, uint, 0644);49 50static DEFINE_PER_CPU(struct cpuidle_device *, acpi_cpuidle_device);51 52struct cpuidle_driver acpi_idle_driver = {53 .name = "acpi_idle",54 .owner = THIS_MODULE,55};56 57#ifdef CONFIG_ACPI_PROCESSOR_CSTATE58static59DEFINE_PER_CPU(struct acpi_processor_cx * [CPUIDLE_STATE_MAX], acpi_cstate);60 61static 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 */73static 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 87static 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 enable106 * interrupts after return.107 */108static void __cpuidle acpi_safe_halt(void)109{110 if (!tif_need_resched()) {111 raw_safe_halt();112 raw_local_irq_disable();113 }114}115 116#ifdef ARCH_APICTIMER_STOPS_ON_C3117 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 vendors121 * are affected too. We pick the most conservative approach: we assume122 * that the local APIC stops in both C2 and C3.123 */124static 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 lapic138 * unstable139 */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 147static void __lapic_timer_propagate_broadcast(void *arg)148{149 struct acpi_processor *pr = arg;150 151 if (pr->power.timer_broadcast_on_state < INT_MAX)152 tick_broadcast_enable();153 else154 tick_broadcast_disable();155}156 157static 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 */164static 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#else171 172static void lapic_timer_check_state(int state, struct acpi_processor *pr,173 struct acpi_processor_cx *cstate) { }174static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { }175 176static bool lapic_timer_needs_broadcast(struct acpi_processor *pr,177 struct acpi_processor_cx *cx)178{179 return false;180}181 182#endif183 184#if defined(CONFIG_X86)185static 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 all195 * 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#else207static void tsc_check_state(int state) { return; }208#endif209 210static 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_CPU221 /*222 * Check for P_LVL2_UP flag before entering C2 and above on223 * an SMP system.224 */225 if ((num_online_cpus() > 1) &&226 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))227 return -ENODEV;228#endif229 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 to240 * 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 to251 * 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 274static 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 291static 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 309static 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 by323 * the erratum), but this is known to disrupt certain ISA324 * devices thus we take the conservative approach.325 */326 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 be359 * 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. Enable372 * checking of bus mastering status (bm_check) so we can373 * use this in our C3 policy374 */375 cx->valid = 1;376 377 /*378 * On older chipsets, BM_RLD needs to be set379 * in order for Bus Master activity to wake the380 * system from C3. Newer chipsets handle DMA381 * during C3 automatically and BM_RLD is a NOP.382 * In either case, the proper way to383 * 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 388static void acpi_cst_latency_sort(struct acpi_processor_cx *states, size_t length)389{390 int i, j, k;391 392 for (i = 1; i < length; i++) {393 if (!states[i].valid)394 continue;395 396 for (j = i - 1, k = i; j >= 0; j--) {397 if (!states[j].valid)398 continue;399 400 if (states[j].latency > states[k].latency)401 swap(states[j].latency, states[k].latency);402 403 k = j;404 }405 }406}407 408static int acpi_processor_power_verify(struct acpi_processor *pr)409{410 unsigned int i;411 unsigned int working = 0;412 unsigned int last_latency = 0;413 unsigned int last_type = 0;414 bool buggy_latency = false;415 416 pr->power.timer_broadcast_on_state = INT_MAX;417 418 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {419 struct acpi_processor_cx *cx = &pr->power.states[i];420 421 switch (cx->type) {422 case ACPI_STATE_C1:423 cx->valid = 1;424 break;425 426 case ACPI_STATE_C2:427 if (!cx->address)428 break;429 cx->valid = 1;430 break;431 432 case ACPI_STATE_C3:433 acpi_processor_power_verify_c3(pr, cx);434 break;435 }436 if (!cx->valid)437 continue;438 if (cx->type >= last_type && cx->latency < last_latency)439 buggy_latency = true;440 last_latency = cx->latency;441 last_type = cx->type;442 443 lapic_timer_check_state(i, pr, cx);444 tsc_check_state(cx->type);445 working++;446 }447 448 if (buggy_latency) {449 pr_notice("FW issue: working around C-state latencies out of order\n");450 acpi_cst_latency_sort(&pr->power.states[1], max_cstate);451 }452 453 lapic_timer_propagate_broadcast(pr);454 455 return working;456}457 458static int acpi_processor_get_cstate_info(struct acpi_processor *pr)459{460 unsigned int i;461 int result;462 463 464 /* NOTE: the idle thread may not be running while calling465 * this function */466 467 /* Zero initialize all the C-states info. */468 memset(pr->power.states, 0, sizeof(pr->power.states));469 470 result = acpi_processor_get_power_info_cst(pr);471 if (result == -ENODEV)472 result = acpi_processor_get_power_info_fadt(pr);473 474 if (result)475 return result;476 477 acpi_processor_get_power_info_default(pr);478 479 pr->power.count = acpi_processor_power_verify(pr);480 481 /*482 * if one state of type C2 or C3 is available, mark this483 * CPU as being "idle manageable"484 */485 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) {486 if (pr->power.states[i].valid) {487 pr->power.count = i;488 pr->flags.power = 1;489 }490 }491 492 return 0;493}494 495/**496 * acpi_idle_bm_check - checks if bus master activity was detected497 */498static int acpi_idle_bm_check(void)499{500 u32 bm_status = 0;501 502 if (bm_check_disable)503 return 0;504 505 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);506 if (bm_status)507 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);508 /*509 * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect510 * the true state of bus mastering activity; forcing us to511 * manually check the BMIDEA bit of each IDE channel.512 */513 else if (errata.piix4.bmisx) {514 if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01)515 || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))516 bm_status = 1;517 }518 return bm_status;519}520 521static __cpuidle void io_idle(unsigned long addr)522{523 /* IO port based C-state */524 inb(addr);525 526#ifdef CONFIG_X86527 /* No delay is needed if we are in guest */528 if (boot_cpu_has(X86_FEATURE_HYPERVISOR))529 return;530 /*531 * Modern (>=Nehalem) Intel systems use ACPI via intel_idle,532 * not this code. Assume that any Intel systems using this533 * are ancient and may need the dummy wait. This also assumes534 * that the motivating chipset issue was Intel-only.535 */536 if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)537 return;538#endif539 /*540 * Dummy wait op - must do something useless after P_LVL2 read541 * because chipsets cannot guarantee that STPCLK# signal gets542 * asserted in time to freeze execution properly543 *544 * This workaround has been in place since the original ACPI545 * implementation was merged, circa 2002.546 *547 * If a profile is pointing to this instruction, please first548 * consider moving your system to a more modern idle549 * mechanism.550 */551 inl(acpi_gbl_FADT.xpm_timer_block.address);552}553 554/**555 * acpi_idle_do_entry - enter idle state using the appropriate method556 * @cx: cstate data557 *558 * Caller disables interrupt before call and enables interrupt after return.559 */560static void __cpuidle acpi_idle_do_entry(struct acpi_processor_cx *cx)561{562 perf_lopwr_cb(true);563 564 if (cx->entry_method == ACPI_CSTATE_FFH) {565 /* Call into architectural FFH based C-state */566 acpi_processor_ffh_cstate_enter(cx);567 } else if (cx->entry_method == ACPI_CSTATE_HALT) {568 acpi_safe_halt();569 } else {570 io_idle(cx->address);571 }572 573 perf_lopwr_cb(false);574}575 576/**577 * acpi_idle_play_dead - enters an ACPI state for long-term idle (i.e. off-lining)578 * @dev: the target CPU579 * @index: the index of suggested state580 */581static int acpi_idle_play_dead(struct cpuidle_device *dev, int index)582{583 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);584 585 ACPI_FLUSH_CPU_CACHE();586 587 while (1) {588 589 if (cx->entry_method == ACPI_CSTATE_HALT)590 raw_safe_halt();591 else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {592 io_idle(cx->address);593 } else594 return -ENODEV;595 }596 597 /* Never reached */598 return 0;599}600 601static __always_inline bool acpi_idle_fallback_to_c1(struct acpi_processor *pr)602{603 return IS_ENABLED(CONFIG_HOTPLUG_CPU) && !pr->flags.has_cst &&604 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED);605}606 607static int c3_cpu_count;608static DEFINE_RAW_SPINLOCK(c3_lock);609 610/**611 * acpi_idle_enter_bm - enters C3 with proper BM handling612 * @drv: cpuidle driver613 * @pr: Target processor614 * @cx: Target state context615 * @index: index of target state616 */617static int __cpuidle acpi_idle_enter_bm(struct cpuidle_driver *drv,618 struct acpi_processor *pr,619 struct acpi_processor_cx *cx,620 int index)621{622 static struct acpi_processor_cx safe_cx = {623 .entry_method = ACPI_CSTATE_HALT,624 };625 626 /*627 * disable bus master628 * bm_check implies we need ARB_DIS629 * bm_control implies whether we can do ARB_DIS630 *631 * That leaves a case where bm_check is set and bm_control is not set.632 * In that case we cannot do much, we enter C3 without doing anything.633 */634 bool dis_bm = pr->flags.bm_control;635 636 instrumentation_begin();637 638 /* If we can skip BM, demote to a safe state. */639 if (!cx->bm_sts_skip && acpi_idle_bm_check()) {640 dis_bm = false;641 index = drv->safe_state_index;642 if (index >= 0) {643 cx = this_cpu_read(acpi_cstate[index]);644 } else {645 cx = &safe_cx;646 index = -EBUSY;647 }648 }649 650 if (dis_bm) {651 raw_spin_lock(&c3_lock);652 c3_cpu_count++;653 /* Disable bus master arbitration when all CPUs are in C3 */654 if (c3_cpu_count == num_online_cpus())655 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1);656 raw_spin_unlock(&c3_lock);657 }658 659 ct_cpuidle_enter();660 661 acpi_idle_do_entry(cx);662 663 ct_cpuidle_exit();664 665 /* Re-enable bus master arbitration */666 if (dis_bm) {667 raw_spin_lock(&c3_lock);668 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0);669 c3_cpu_count--;670 raw_spin_unlock(&c3_lock);671 }672 673 instrumentation_end();674 675 return index;676}677 678static int __cpuidle acpi_idle_enter(struct cpuidle_device *dev,679 struct cpuidle_driver *drv, int index)680{681 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);682 struct acpi_processor *pr;683 684 pr = __this_cpu_read(processors);685 if (unlikely(!pr))686 return -EINVAL;687 688 if (cx->type != ACPI_STATE_C1) {689 if (cx->type == ACPI_STATE_C3 && pr->flags.bm_check)690 return acpi_idle_enter_bm(drv, pr, cx, index);691 692 /* C2 to C1 demotion. */693 if (acpi_idle_fallback_to_c1(pr) && num_online_cpus() > 1) {694 index = ACPI_IDLE_STATE_START;695 cx = per_cpu(acpi_cstate[index], dev->cpu);696 }697 }698 699 if (cx->type == ACPI_STATE_C3)700 ACPI_FLUSH_CPU_CACHE();701 702 acpi_idle_do_entry(cx);703 704 return index;705}706 707static int __cpuidle acpi_idle_enter_s2idle(struct cpuidle_device *dev,708 struct cpuidle_driver *drv, int index)709{710 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);711 712 if (cx->type == ACPI_STATE_C3) {713 struct acpi_processor *pr = __this_cpu_read(processors);714 715 if (unlikely(!pr))716 return 0;717 718 if (pr->flags.bm_check) {719 u8 bm_sts_skip = cx->bm_sts_skip;720 721 /* Don't check BM_STS, do an unconditional ARB_DIS for S2IDLE */722 cx->bm_sts_skip = 1;723 acpi_idle_enter_bm(drv, pr, cx, index);724 cx->bm_sts_skip = bm_sts_skip;725 726 return 0;727 } else {728 ACPI_FLUSH_CPU_CACHE();729 }730 }731 acpi_idle_do_entry(cx);732 733 return 0;734}735 736static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,737 struct cpuidle_device *dev)738{739 int i, count = ACPI_IDLE_STATE_START;740 struct acpi_processor_cx *cx;741 struct cpuidle_state *state;742 743 if (max_cstate == 0)744 max_cstate = 1;745 746 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {747 state = &acpi_idle_driver.states[count];748 cx = &pr->power.states[i];749 750 if (!cx->valid)751 continue;752 753 per_cpu(acpi_cstate[count], dev->cpu) = cx;754 755 if (lapic_timer_needs_broadcast(pr, cx))756 state->flags |= CPUIDLE_FLAG_TIMER_STOP;757 758 if (cx->type == ACPI_STATE_C3) {759 state->flags |= CPUIDLE_FLAG_TLB_FLUSHED;760 if (pr->flags.bm_check)761 state->flags |= CPUIDLE_FLAG_RCU_IDLE;762 }763 764 count++;765 if (count == CPUIDLE_STATE_MAX)766 break;767 }768 769 if (!count)770 return -EINVAL;771 772 return 0;773}774 775static int acpi_processor_setup_cstates(struct acpi_processor *pr)776{777 int i, count;778 struct acpi_processor_cx *cx;779 struct cpuidle_state *state;780 struct cpuidle_driver *drv = &acpi_idle_driver;781 782 if (max_cstate == 0)783 max_cstate = 1;784 785 if (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX)) {786 cpuidle_poll_state_init(drv);787 count = 1;788 } else {789 count = 0;790 }791 792 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {793 cx = &pr->power.states[i];794 795 if (!cx->valid)796 continue;797 798 state = &drv->states[count];799 snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);800 strscpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);801 state->exit_latency = cx->latency;802 state->target_residency = cx->latency * latency_factor;803 state->enter = acpi_idle_enter;804 805 state->flags = 0;806 if (cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2 ||807 cx->type == ACPI_STATE_C3) {808 state->enter_dead = acpi_idle_play_dead;809 if (cx->type != ACPI_STATE_C3)810 drv->safe_state_index = count;811 }812 /*813 * Halt-induced C1 is not good for ->enter_s2idle, because it814 * re-enables interrupts on exit. Moreover, C1 is generally not815 * particularly interesting from the suspend-to-idle angle, so816 * avoid C1 and the situations in which we may need to fall back817 * to it altogether.818 */819 if (cx->type != ACPI_STATE_C1 && !acpi_idle_fallback_to_c1(pr))820 state->enter_s2idle = acpi_idle_enter_s2idle;821 822 count++;823 if (count == CPUIDLE_STATE_MAX)824 break;825 }826 827 drv->state_count = count;828 829 if (!count)830 return -EINVAL;831 832 return 0;833}834 835static inline void acpi_processor_cstate_first_run_checks(void)836{837 static int first_run;838 839 if (first_run)840 return;841 dmi_check_system(processor_power_dmi_table);842 max_cstate = acpi_processor_cstate_check(max_cstate);843 if (max_cstate < ACPI_C_STATES_MAX)844 pr_notice("processor limited to max C-state %d\n", max_cstate);845 846 first_run++;847 848 if (nocst)849 return;850 851 acpi_processor_claim_cst_control();852}853#else854 855static inline int disabled_by_idle_boot_param(void) { return 0; }856static inline void acpi_processor_cstate_first_run_checks(void) { }857static int acpi_processor_get_cstate_info(struct acpi_processor *pr)858{859 return -ENODEV;860}861 862static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,863 struct cpuidle_device *dev)864{865 return -EINVAL;866}867 868static int acpi_processor_setup_cstates(struct acpi_processor *pr)869{870 return -EINVAL;871}872 873#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */874 875struct acpi_lpi_states_array {876 unsigned int size;877 unsigned int composite_states_size;878 struct acpi_lpi_state *entries;879 struct acpi_lpi_state *composite_states[ACPI_PROCESSOR_MAX_POWER];880};881 882static int obj_get_integer(union acpi_object *obj, u32 *value)883{884 if (obj->type != ACPI_TYPE_INTEGER)885 return -EINVAL;886 887 *value = obj->integer.value;888 return 0;889}890 891static int acpi_processor_evaluate_lpi(acpi_handle handle,892 struct acpi_lpi_states_array *info)893{894 acpi_status status;895 int ret = 0;896 int pkg_count, state_idx = 1, loop;897 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };898 union acpi_object *lpi_data;899 struct acpi_lpi_state *lpi_state;900 901 status = acpi_evaluate_object(handle, "_LPI", NULL, &buffer);902 if (ACPI_FAILURE(status)) {903 acpi_handle_debug(handle, "No _LPI, giving up\n");904 return -ENODEV;905 }906 907 lpi_data = buffer.pointer;908 909 /* There must be at least 4 elements = 3 elements + 1 package */910 if (!lpi_data || lpi_data->type != ACPI_TYPE_PACKAGE ||911 lpi_data->package.count < 4) {912 pr_debug("not enough elements in _LPI\n");913 ret = -ENODATA;914 goto end;915 }916 917 pkg_count = lpi_data->package.elements[2].integer.value;918 919 /* Validate number of power states. */920 if (pkg_count < 1 || pkg_count != lpi_data->package.count - 3) {921 pr_debug("count given by _LPI is not valid\n");922 ret = -ENODATA;923 goto end;924 }925 926 lpi_state = kcalloc(pkg_count, sizeof(*lpi_state), GFP_KERNEL);927 if (!lpi_state) {928 ret = -ENOMEM;929 goto end;930 }931 932 info->size = pkg_count;933 info->entries = lpi_state;934 935 /* LPI States start at index 3 */936 for (loop = 3; state_idx <= pkg_count; loop++, state_idx++, lpi_state++) {937 union acpi_object *element, *pkg_elem, *obj;938 939 element = &lpi_data->package.elements[loop];940 if (element->type != ACPI_TYPE_PACKAGE || element->package.count < 7)941 continue;942 943 pkg_elem = element->package.elements;944 945 obj = pkg_elem + 6;946 if (obj->type == ACPI_TYPE_BUFFER) {947 struct acpi_power_register *reg;948 949 reg = (struct acpi_power_register *)obj->buffer.pointer;950 if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO &&951 reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)952 continue;953 954 lpi_state->address = reg->address;955 lpi_state->entry_method =956 reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE ?957 ACPI_CSTATE_FFH : ACPI_CSTATE_SYSTEMIO;958 } else if (obj->type == ACPI_TYPE_INTEGER) {959 lpi_state->entry_method = ACPI_CSTATE_INTEGER;960 lpi_state->address = obj->integer.value;961 } else {962 continue;963 }964 965 /* elements[7,8] skipped for now i.e. Residency/Usage counter*/966 967 obj = pkg_elem + 9;968 if (obj->type == ACPI_TYPE_STRING)969 strscpy(lpi_state->desc, obj->string.pointer,970 ACPI_CX_DESC_LEN);971 972 lpi_state->index = state_idx;973 if (obj_get_integer(pkg_elem + 0, &lpi_state->min_residency)) {974 pr_debug("No min. residency found, assuming 10 us\n");975 lpi_state->min_residency = 10;976 }977 978 if (obj_get_integer(pkg_elem + 1, &lpi_state->wake_latency)) {979 pr_debug("No wakeup residency found, assuming 10 us\n");980 lpi_state->wake_latency = 10;981 }982 983 if (obj_get_integer(pkg_elem + 2, &lpi_state->flags))984 lpi_state->flags = 0;985 986 if (obj_get_integer(pkg_elem + 3, &lpi_state->arch_flags))987 lpi_state->arch_flags = 0;988 989 if (obj_get_integer(pkg_elem + 4, &lpi_state->res_cnt_freq))990 lpi_state->res_cnt_freq = 1;991 992 if (obj_get_integer(pkg_elem + 5, &lpi_state->enable_parent_state))993 lpi_state->enable_parent_state = 0;994 }995 996 acpi_handle_debug(handle, "Found %d power states\n", state_idx);997end:998 kfree(buffer.pointer);999 return ret;1000}1001 1002/*1003 * flat_state_cnt - the number of composite LPI states after the process of flattening1004 */1005static int flat_state_cnt;1006 1007/**1008 * combine_lpi_states - combine local and parent LPI states to form a composite LPI state1009 *1010 * @local: local LPI state1011 * @parent: parent LPI state1012 * @result: composite LPI state1013 */1014static bool combine_lpi_states(struct acpi_lpi_state *local,1015 struct acpi_lpi_state *parent,1016 struct acpi_lpi_state *result)1017{1018 if (parent->entry_method == ACPI_CSTATE_INTEGER) {1019 if (!parent->address) /* 0 means autopromotable */1020 return false;1021 result->address = local->address + parent->address;1022 } else {1023 result->address = parent->address;1024 }1025 1026 result->min_residency = max(local->min_residency, parent->min_residency);1027 result->wake_latency = local->wake_latency + parent->wake_latency;1028 result->enable_parent_state = parent->enable_parent_state;1029 result->entry_method = local->entry_method;1030 1031 result->flags = parent->flags;1032 result->arch_flags = parent->arch_flags;1033 result->index = parent->index;1034 1035 strscpy(result->desc, local->desc, ACPI_CX_DESC_LEN);1036 strlcat(result->desc, "+", ACPI_CX_DESC_LEN);1037 strlcat(result->desc, parent->desc, ACPI_CX_DESC_LEN);1038 return true;1039}1040 1041#define ACPI_LPI_STATE_FLAGS_ENABLED BIT(0)1042 1043static void stash_composite_state(struct acpi_lpi_states_array *curr_level,1044 struct acpi_lpi_state *t)1045{1046 curr_level->composite_states[curr_level->composite_states_size++] = t;1047}1048 1049static int flatten_lpi_states(struct acpi_processor *pr,1050 struct acpi_lpi_states_array *curr_level,1051 struct acpi_lpi_states_array *prev_level)1052{1053 int i, j, state_count = curr_level->size;1054 struct acpi_lpi_state *p, *t = curr_level->entries;1055 1056 curr_level->composite_states_size = 0;1057 for (j = 0; j < state_count; j++, t++) {1058 struct acpi_lpi_state *flpi;1059 1060 if (!(t->flags & ACPI_LPI_STATE_FLAGS_ENABLED))1061 continue;1062 1063 if (flat_state_cnt >= ACPI_PROCESSOR_MAX_POWER) {1064 pr_warn("Limiting number of LPI states to max (%d)\n",1065 ACPI_PROCESSOR_MAX_POWER);1066 pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");1067 break;1068 }1069 1070 flpi = &pr->power.lpi_states[flat_state_cnt];1071 1072 if (!prev_level) { /* leaf/processor node */1073 memcpy(flpi, t, sizeof(*t));1074 stash_composite_state(curr_level, flpi);1075 flat_state_cnt++;1076 continue;1077 }1078 1079 for (i = 0; i < prev_level->composite_states_size; i++) {1080 p = prev_level->composite_states[i];1081 if (t->index <= p->enable_parent_state &&1082 combine_lpi_states(p, t, flpi)) {1083 stash_composite_state(curr_level, flpi);1084 flat_state_cnt++;1085 flpi++;1086 }1087 }1088 }1089 1090 kfree(curr_level->entries);1091 return 0;1092}1093 1094int __weak acpi_processor_ffh_lpi_probe(unsigned int cpu)1095{1096 return -EOPNOTSUPP;1097}1098 1099static int acpi_processor_get_lpi_info(struct acpi_processor *pr)1100{1101 int ret, i;1102 acpi_status status;1103 acpi_handle handle = pr->handle, pr_ahandle;1104 struct acpi_device *d = NULL;1105 struct acpi_lpi_states_array info[2], *tmp, *prev, *curr;1106 1107 /* make sure our architecture has support */1108 ret = acpi_processor_ffh_lpi_probe(pr->id);1109 if (ret == -EOPNOTSUPP)1110 return ret;1111 1112 if (!osc_pc_lpi_support_confirmed)1113 return -EOPNOTSUPP;1114 1115 if (!acpi_has_method(handle, "_LPI"))1116 return -EINVAL;1117 1118 flat_state_cnt = 0;1119 prev = &info[0];1120 curr = &info[1];1121 handle = pr->handle;1122 ret = acpi_processor_evaluate_lpi(handle, prev);1123 if (ret)1124 return ret;1125 flatten_lpi_states(pr, prev, NULL);1126 1127 status = acpi_get_parent(handle, &pr_ahandle);1128 while (ACPI_SUCCESS(status)) {1129 d = acpi_fetch_acpi_dev(pr_ahandle);1130 if (!d)1131 break;1132 1133 handle = pr_ahandle;1134 1135 if (strcmp(acpi_device_hid(d), ACPI_PROCESSOR_CONTAINER_HID))1136 break;1137 1138 /* can be optional ? */1139 if (!acpi_has_method(handle, "_LPI"))1140 break;1141 1142 ret = acpi_processor_evaluate_lpi(handle, curr);1143 if (ret)1144 break;1145 1146 /* flatten all the LPI states in this level of hierarchy */1147 flatten_lpi_states(pr, curr, prev);1148 1149 tmp = prev, prev = curr, curr = tmp;1150 1151 status = acpi_get_parent(handle, &pr_ahandle);1152 }1153 1154 pr->power.count = flat_state_cnt;1155 /* reset the index after flattening */1156 for (i = 0; i < pr->power.count; i++)1157 pr->power.lpi_states[i].index = i;1158 1159 /* Tell driver that _LPI is supported. */1160 pr->flags.has_lpi = 1;1161 pr->flags.power = 1;1162 1163 return 0;1164}1165 1166int __weak acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi)1167{1168 return -ENODEV;1169}1170 1171/**1172 * acpi_idle_lpi_enter - enters an ACPI any LPI state1173 * @dev: the target CPU1174 * @drv: cpuidle driver containing cpuidle state info1175 * @index: index of target state1176 *1177 * Return: 0 for success or negative value for error1178 */1179static int acpi_idle_lpi_enter(struct cpuidle_device *dev,1180 struct cpuidle_driver *drv, int index)1181{1182 struct acpi_processor *pr;1183 struct acpi_lpi_state *lpi;1184 1185 pr = __this_cpu_read(processors);1186 1187 if (unlikely(!pr))1188 return -EINVAL;1189 1190 lpi = &pr->power.lpi_states[index];1191 if (lpi->entry_method == ACPI_CSTATE_FFH)1192 return acpi_processor_ffh_lpi_enter(lpi);1193 1194 return -EINVAL;1195}1196 1197static int acpi_processor_setup_lpi_states(struct acpi_processor *pr)1198{1199 int i;1200 struct acpi_lpi_state *lpi;1201 struct cpuidle_state *state;1202 struct cpuidle_driver *drv = &acpi_idle_driver;1203 1204 if (!pr->flags.has_lpi)1205 return -EOPNOTSUPP;1206 1207 for (i = 0; i < pr->power.count && i < CPUIDLE_STATE_MAX; i++) {1208 lpi = &pr->power.lpi_states[i];1209 1210 state = &drv->states[i];1211 snprintf(state->name, CPUIDLE_NAME_LEN, "LPI-%d", i);1212 strscpy(state->desc, lpi->desc, CPUIDLE_DESC_LEN);1213 state->exit_latency = lpi->wake_latency;1214 state->target_residency = lpi->min_residency;1215 state->flags |= arch_get_idle_state_flags(lpi->arch_flags);1216 if (i != 0 && lpi->entry_method == ACPI_CSTATE_FFH)1217 state->flags |= CPUIDLE_FLAG_RCU_IDLE;1218 state->enter = acpi_idle_lpi_enter;1219 drv->safe_state_index = i;1220 }1221 1222 drv->state_count = i;1223 1224 return 0;1225}1226 1227/**1228 * acpi_processor_setup_cpuidle_states- prepares and configures cpuidle1229 * global state data i.e. idle routines1230 *1231 * @pr: the ACPI processor1232 */1233static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)1234{1235 int i;1236 struct cpuidle_driver *drv = &acpi_idle_driver;1237 1238 if (!pr->flags.power_setup_done || !pr->flags.power)1239 return -EINVAL;1240 1241 drv->safe_state_index = -1;1242 for (i = ACPI_IDLE_STATE_START; i < CPUIDLE_STATE_MAX; i++) {1243 drv->states[i].name[0] = '\0';1244 drv->states[i].desc[0] = '\0';1245 }1246 1247 if (pr->flags.has_lpi)1248 return acpi_processor_setup_lpi_states(pr);1249 1250 return acpi_processor_setup_cstates(pr);1251}1252 1253/**1254 * acpi_processor_setup_cpuidle_dev - prepares and configures CPUIDLE1255 * device i.e. per-cpu data1256 *1257 * @pr: the ACPI processor1258 * @dev : the cpuidle device1259 */1260static int acpi_processor_setup_cpuidle_dev(struct acpi_processor *pr,1261 struct cpuidle_device *dev)1262{1263 if (!pr->flags.power_setup_done || !pr->flags.power || !dev)1264 return -EINVAL;1265 1266 dev->cpu = pr->id;1267 if (pr->flags.has_lpi)1268 return acpi_processor_ffh_lpi_probe(pr->id);1269 1270 return acpi_processor_setup_cpuidle_cx(pr, dev);1271}1272 1273static int acpi_processor_get_power_info(struct acpi_processor *pr)1274{1275 int ret;1276 1277 ret = acpi_processor_get_lpi_info(pr);1278 if (ret)1279 ret = acpi_processor_get_cstate_info(pr);1280 1281 return ret;1282}1283 1284int acpi_processor_hotplug(struct acpi_processor *pr)1285{1286 int ret = 0;1287 struct cpuidle_device *dev;1288 1289 if (disabled_by_idle_boot_param())1290 return 0;1291 1292 if (!pr->flags.power_setup_done)1293 return -ENODEV;1294 1295 dev = per_cpu(acpi_cpuidle_device, pr->id);1296 cpuidle_pause_and_lock();1297 cpuidle_disable_device(dev);1298 ret = acpi_processor_get_power_info(pr);1299 if (!ret && pr->flags.power) {1300 acpi_processor_setup_cpuidle_dev(pr, dev);1301 ret = cpuidle_enable_device(dev);1302 }1303 cpuidle_resume_and_unlock();1304 1305 return ret;1306}1307 1308int acpi_processor_power_state_has_changed(struct acpi_processor *pr)1309{1310 int cpu;1311 struct acpi_processor *_pr;1312 struct cpuidle_device *dev;1313 1314 if (disabled_by_idle_boot_param())1315 return 0;1316 1317 if (!pr->flags.power_setup_done)1318 return -ENODEV;1319 1320 /*1321 * FIXME: Design the ACPI notification to make it once per1322 * system instead of once per-cpu. This condition is a hack1323 * to make the code that updates C-States be called once.1324 */1325 1326 if (pr->id == 0 && cpuidle_get_driver() == &acpi_idle_driver) {1327 1328 /* Protect against cpu-hotplug */1329 cpus_read_lock();1330 cpuidle_pause_and_lock();1331 1332 /* Disable all cpuidle devices */1333 for_each_online_cpu(cpu) {1334 _pr = per_cpu(processors, cpu);1335 if (!_pr || !_pr->flags.power_setup_done)1336 continue;1337 dev = per_cpu(acpi_cpuidle_device, cpu);1338 cpuidle_disable_device(dev);1339 }1340 1341 /* Populate Updated C-state information */1342 acpi_processor_get_power_info(pr);1343 acpi_processor_setup_cpuidle_states(pr);1344 1345 /* Enable all cpuidle devices */1346 for_each_online_cpu(cpu) {1347 _pr = per_cpu(processors, cpu);1348 if (!_pr || !_pr->flags.power_setup_done)1349 continue;1350 acpi_processor_get_power_info(_pr);1351 if (_pr->flags.power) {1352 dev = per_cpu(acpi_cpuidle_device, cpu);1353 acpi_processor_setup_cpuidle_dev(_pr, dev);1354 cpuidle_enable_device(dev);1355 }1356 }1357 cpuidle_resume_and_unlock();1358 cpus_read_unlock();1359 }1360 1361 return 0;1362}1363 1364static int acpi_processor_registered;1365 1366int acpi_processor_power_init(struct acpi_processor *pr)1367{1368 int retval;1369 struct cpuidle_device *dev;1370 1371 if (disabled_by_idle_boot_param())1372 return 0;1373 1374 acpi_processor_cstate_first_run_checks();1375 1376 if (!acpi_processor_get_power_info(pr))1377 pr->flags.power_setup_done = 1;1378 1379 /*1380 * Install the idle handler if processor power management is supported.1381 * Note that we use previously set idle handler will be used on1382 * platforms that only support C1.1383 */1384 if (pr->flags.power) {1385 /* Register acpi_idle_driver if not already registered */1386 if (!acpi_processor_registered) {1387 acpi_processor_setup_cpuidle_states(pr);1388 retval = cpuidle_register_driver(&acpi_idle_driver);1389 if (retval)1390 return retval;1391 pr_debug("%s registered with cpuidle\n",1392 acpi_idle_driver.name);1393 }1394 1395 dev = kzalloc(sizeof(*dev), GFP_KERNEL);1396 if (!dev)1397 return -ENOMEM;1398 per_cpu(acpi_cpuidle_device, pr->id) = dev;1399 1400 acpi_processor_setup_cpuidle_dev(pr, dev);1401 1402 /* Register per-cpu cpuidle_device. Cpuidle driver1403 * must already be registered before registering device1404 */1405 retval = cpuidle_register_device(dev);1406 if (retval) {1407 if (acpi_processor_registered == 0)1408 cpuidle_unregister_driver(&acpi_idle_driver);1409 return retval;1410 }1411 acpi_processor_registered++;1412 }1413 return 0;1414}1415 1416int acpi_processor_power_exit(struct acpi_processor *pr)1417{1418 struct cpuidle_device *dev = per_cpu(acpi_cpuidle_device, pr->id);1419 1420 if (disabled_by_idle_boot_param())1421 return 0;1422 1423 if (pr->flags.power) {1424 cpuidle_unregister_device(dev);1425 acpi_processor_registered--;1426 if (acpi_processor_registered == 0)1427 cpuidle_unregister_driver(&acpi_idle_driver);1428 1429 kfree(dev);1430 }1431 1432 pr->flags.power_setup_done = 0;1433 return 0;1434}1435