1 // SPDX-License-Identifier: GPL-2.0-only
3 * intel_idle.c - native hardware idle loop for modern Intel processors
5 * Copyright (c) 2013 - 2020, Intel Corporation.
6 * Len Brown <len.brown@intel.com>
7 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
11 * intel_idle is a cpuidle driver that loads on all Intel CPUs with MWAIT
12 * in lieu of the legacy ACPI processor_idle driver. The intent is to
13 * make Linux more efficient on these processors, as intel_idle knows
14 * more than ACPI, as well as make Linux more immune to ACPI BIOS bugs.
20 * All CPUs have same idle states as boot CPU
22 * Chipset BM_STS (bus master status) bit is a NOP
23 * for preventing entry into deep C-states
25 * CPU will flush caches as needed when entering a C-state via MWAIT
26 * (in contrast to entering ACPI C3, in which case the WBINVD
27 * instruction needs to be executed to flush the caches)
33 * ACPI has a .suspend hack to turn off deep c-statees during suspend
34 * to avoid complications with the lapic timer workaround.
35 * Have not seen issues with suspend, but may need same workaround here.
39 /* un-comment DEBUG to enable pr_debug() statements */
42 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
44 #include <linux/acpi.h>
45 #include <linux/kernel.h>
46 #include <linux/cpuidle.h>
47 #include <linux/tick.h>
48 #include <trace/events/power.h>
49 #include <linux/sched.h>
50 #include <linux/sched/smt.h>
51 #include <linux/notifier.h>
52 #include <linux/cpu.h>
53 #include <linux/moduleparam.h>
54 #include <asm/cpu_device_id.h>
55 #include <asm/intel-family.h>
56 #include <asm/nospec-branch.h>
57 #include <asm/mwait.h>
59 #include <asm/fpu/api.h>
61 #define INTEL_IDLE_VERSION "0.5.1"
63 static struct cpuidle_driver intel_idle_driver = {
67 /* intel_idle.max_cstate=0 disables driver */
68 static int max_cstate = CPUIDLE_STATE_MAX - 1;
69 static unsigned int disabled_states_mask;
70 static unsigned int preferred_states_mask;
72 static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
74 static unsigned long auto_demotion_disable_flags;
77 C1E_PROMOTION_PRESERVE,
80 } c1e_promotion = C1E_PROMOTION_PRESERVE;
83 struct cpuidle_state *state_table;
86 * Hardware C-state auto-demotion may not always be optimal.
87 * Indicate which enable bits to clear here.
89 unsigned long auto_demotion_disable_flags;
90 bool byt_auto_demotion_disable_flag;
91 bool disable_promotion_to_c1e;
95 static const struct idle_cpu *icpu __initdata;
96 static struct cpuidle_state *cpuidle_state_table __initdata;
98 static unsigned int mwait_substates __initdata;
101 * Enable interrupts before entering the C-state. On some platforms and for
102 * some C-states, this may measurably decrease interrupt latency.
104 #define CPUIDLE_FLAG_IRQ_ENABLE BIT(14)
107 * Enable this state by default even if the ACPI _CST does not list it.
109 #define CPUIDLE_FLAG_ALWAYS_ENABLE BIT(15)
112 * Disable IBRS across idle (when KERNEL_IBRS), is exclusive vs IRQ_ENABLE
115 #define CPUIDLE_FLAG_IBRS BIT(16)
118 * Initialize large xstate for the C6-state entrance.
120 #define CPUIDLE_FLAG_INIT_XSTATE BIT(17)
123 * MWAIT takes an 8-bit "hint" in EAX "suggesting"
124 * the C-state (top nibble) and sub-state (bottom nibble)
125 * 0x00 means "MWAIT(C1)", 0x10 means "MWAIT(C2)" etc.
127 * We store the hint at the top of our "flags" for each state.
129 #define flg2MWAIT(flags) (((flags) >> 24) & 0xFF)
130 #define MWAIT2flg(eax) ((eax & 0xFF) << 24)
132 static __always_inline int __intel_idle(struct cpuidle_device *dev,
133 struct cpuidle_driver *drv, int index)
135 struct cpuidle_state *state = &drv->states[index];
136 unsigned long eax = flg2MWAIT(state->flags);
137 unsigned long ecx = 1; /* break on interrupt flag */
139 mwait_idle_with_hints(eax, ecx);
145 * intel_idle - Ask the processor to enter the given idle state.
146 * @dev: cpuidle device of the target CPU.
147 * @drv: cpuidle driver (assumed to point to intel_idle_driver).
148 * @index: Target idle state index.
150 * Use the MWAIT instruction to notify the processor that the CPU represented by
151 * @dev is idle and it can try to enter the idle state corresponding to @index.
153 * If the local APIC timer is not known to be reliable in the target idle state,
154 * enable one-shot tick broadcasting for the target CPU before executing MWAIT.
156 * Must be called under local_irq_disable().
158 static __cpuidle int intel_idle(struct cpuidle_device *dev,
159 struct cpuidle_driver *drv, int index)
161 return __intel_idle(dev, drv, index);
164 static __cpuidle int intel_idle_irq(struct cpuidle_device *dev,
165 struct cpuidle_driver *drv, int index)
169 raw_local_irq_enable();
170 ret = __intel_idle(dev, drv, index);
173 * The lockdep hardirqs state may be changed to 'on' with timer
174 * tick interrupt followed by __do_softirq(). Use local_irq_disable()
175 * to keep the hardirqs state correct.
182 static __cpuidle int intel_idle_ibrs(struct cpuidle_device *dev,
183 struct cpuidle_driver *drv, int index)
185 bool smt_active = sched_smt_active();
186 u64 spec_ctrl = spec_ctrl_current();
190 wrmsrl(MSR_IA32_SPEC_CTRL, 0);
192 ret = __intel_idle(dev, drv, index);
195 wrmsrl(MSR_IA32_SPEC_CTRL, spec_ctrl);
200 static __cpuidle int intel_idle_xstate(struct cpuidle_device *dev,
201 struct cpuidle_driver *drv, int index)
204 return __intel_idle(dev, drv, index);
208 * intel_idle_s2idle - Ask the processor to enter the given idle state.
209 * @dev: cpuidle device of the target CPU.
210 * @drv: cpuidle driver (assumed to point to intel_idle_driver).
211 * @index: Target idle state index.
213 * Use the MWAIT instruction to notify the processor that the CPU represented by
214 * @dev is idle and it can try to enter the idle state corresponding to @index.
216 * Invoked as a suspend-to-idle callback routine with frozen user space, frozen
217 * scheduler tick and suspended scheduler clock on the target CPU.
219 static __cpuidle int intel_idle_s2idle(struct cpuidle_device *dev,
220 struct cpuidle_driver *drv, int index)
222 unsigned long ecx = 1; /* break on interrupt flag */
223 struct cpuidle_state *state = &drv->states[index];
224 unsigned long eax = flg2MWAIT(state->flags);
226 if (state->flags & CPUIDLE_FLAG_INIT_XSTATE)
229 mwait_idle_with_hints(eax, ecx);
235 * States are indexed by the cstate number,
236 * which is also the index into the MWAIT hint array.
237 * Thus C0 is a dummy.
239 static struct cpuidle_state nehalem_cstates[] __initdata = {
242 .desc = "MWAIT 0x00",
243 .flags = MWAIT2flg(0x00),
245 .target_residency = 6,
246 .enter = &intel_idle,
247 .enter_s2idle = intel_idle_s2idle, },
250 .desc = "MWAIT 0x01",
251 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
253 .target_residency = 20,
254 .enter = &intel_idle,
255 .enter_s2idle = intel_idle_s2idle, },
258 .desc = "MWAIT 0x10",
259 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
261 .target_residency = 80,
262 .enter = &intel_idle,
263 .enter_s2idle = intel_idle_s2idle, },
266 .desc = "MWAIT 0x20",
267 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
269 .target_residency = 800,
270 .enter = &intel_idle,
271 .enter_s2idle = intel_idle_s2idle, },
276 static struct cpuidle_state snb_cstates[] __initdata = {
279 .desc = "MWAIT 0x00",
280 .flags = MWAIT2flg(0x00),
282 .target_residency = 2,
283 .enter = &intel_idle,
284 .enter_s2idle = intel_idle_s2idle, },
287 .desc = "MWAIT 0x01",
288 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
290 .target_residency = 20,
291 .enter = &intel_idle,
292 .enter_s2idle = intel_idle_s2idle, },
295 .desc = "MWAIT 0x10",
296 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
298 .target_residency = 211,
299 .enter = &intel_idle,
300 .enter_s2idle = intel_idle_s2idle, },
303 .desc = "MWAIT 0x20",
304 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
306 .target_residency = 345,
307 .enter = &intel_idle,
308 .enter_s2idle = intel_idle_s2idle, },
311 .desc = "MWAIT 0x30",
312 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
314 .target_residency = 345,
315 .enter = &intel_idle,
316 .enter_s2idle = intel_idle_s2idle, },
321 static struct cpuidle_state byt_cstates[] __initdata = {
324 .desc = "MWAIT 0x00",
325 .flags = MWAIT2flg(0x00),
327 .target_residency = 1,
328 .enter = &intel_idle,
329 .enter_s2idle = intel_idle_s2idle, },
332 .desc = "MWAIT 0x58",
333 .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
335 .target_residency = 275,
336 .enter = &intel_idle,
337 .enter_s2idle = intel_idle_s2idle, },
340 .desc = "MWAIT 0x52",
341 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
343 .target_residency = 560,
344 .enter = &intel_idle,
345 .enter_s2idle = intel_idle_s2idle, },
348 .desc = "MWAIT 0x60",
349 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
350 .exit_latency = 1200,
351 .target_residency = 4000,
352 .enter = &intel_idle,
353 .enter_s2idle = intel_idle_s2idle, },
356 .desc = "MWAIT 0x64",
357 .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
358 .exit_latency = 10000,
359 .target_residency = 20000,
360 .enter = &intel_idle,
361 .enter_s2idle = intel_idle_s2idle, },
366 static struct cpuidle_state cht_cstates[] __initdata = {
369 .desc = "MWAIT 0x00",
370 .flags = MWAIT2flg(0x00),
372 .target_residency = 1,
373 .enter = &intel_idle,
374 .enter_s2idle = intel_idle_s2idle, },
377 .desc = "MWAIT 0x58",
378 .flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
380 .target_residency = 275,
381 .enter = &intel_idle,
382 .enter_s2idle = intel_idle_s2idle, },
385 .desc = "MWAIT 0x52",
386 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
388 .target_residency = 560,
389 .enter = &intel_idle,
390 .enter_s2idle = intel_idle_s2idle, },
393 .desc = "MWAIT 0x60",
394 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
395 .exit_latency = 1200,
396 .target_residency = 4000,
397 .enter = &intel_idle,
398 .enter_s2idle = intel_idle_s2idle, },
401 .desc = "MWAIT 0x64",
402 .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
403 .exit_latency = 10000,
404 .target_residency = 20000,
405 .enter = &intel_idle,
406 .enter_s2idle = intel_idle_s2idle, },
411 static struct cpuidle_state ivb_cstates[] __initdata = {
414 .desc = "MWAIT 0x00",
415 .flags = MWAIT2flg(0x00),
417 .target_residency = 1,
418 .enter = &intel_idle,
419 .enter_s2idle = intel_idle_s2idle, },
422 .desc = "MWAIT 0x01",
423 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
425 .target_residency = 20,
426 .enter = &intel_idle,
427 .enter_s2idle = intel_idle_s2idle, },
430 .desc = "MWAIT 0x10",
431 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
433 .target_residency = 156,
434 .enter = &intel_idle,
435 .enter_s2idle = intel_idle_s2idle, },
438 .desc = "MWAIT 0x20",
439 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
441 .target_residency = 300,
442 .enter = &intel_idle,
443 .enter_s2idle = intel_idle_s2idle, },
446 .desc = "MWAIT 0x30",
447 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
449 .target_residency = 300,
450 .enter = &intel_idle,
451 .enter_s2idle = intel_idle_s2idle, },
456 static struct cpuidle_state ivt_cstates[] __initdata = {
459 .desc = "MWAIT 0x00",
460 .flags = MWAIT2flg(0x00),
462 .target_residency = 1,
463 .enter = &intel_idle,
464 .enter_s2idle = intel_idle_s2idle, },
467 .desc = "MWAIT 0x01",
468 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
470 .target_residency = 80,
471 .enter = &intel_idle,
472 .enter_s2idle = intel_idle_s2idle, },
475 .desc = "MWAIT 0x10",
476 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
478 .target_residency = 156,
479 .enter = &intel_idle,
480 .enter_s2idle = intel_idle_s2idle, },
483 .desc = "MWAIT 0x20",
484 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
486 .target_residency = 300,
487 .enter = &intel_idle,
488 .enter_s2idle = intel_idle_s2idle, },
493 static struct cpuidle_state ivt_cstates_4s[] __initdata = {
496 .desc = "MWAIT 0x00",
497 .flags = MWAIT2flg(0x00),
499 .target_residency = 1,
500 .enter = &intel_idle,
501 .enter_s2idle = intel_idle_s2idle, },
504 .desc = "MWAIT 0x01",
505 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
507 .target_residency = 250,
508 .enter = &intel_idle,
509 .enter_s2idle = intel_idle_s2idle, },
512 .desc = "MWAIT 0x10",
513 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
515 .target_residency = 300,
516 .enter = &intel_idle,
517 .enter_s2idle = intel_idle_s2idle, },
520 .desc = "MWAIT 0x20",
521 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
523 .target_residency = 400,
524 .enter = &intel_idle,
525 .enter_s2idle = intel_idle_s2idle, },
530 static struct cpuidle_state ivt_cstates_8s[] __initdata = {
533 .desc = "MWAIT 0x00",
534 .flags = MWAIT2flg(0x00),
536 .target_residency = 1,
537 .enter = &intel_idle,
538 .enter_s2idle = intel_idle_s2idle, },
541 .desc = "MWAIT 0x01",
542 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
544 .target_residency = 500,
545 .enter = &intel_idle,
546 .enter_s2idle = intel_idle_s2idle, },
549 .desc = "MWAIT 0x10",
550 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
552 .target_residency = 600,
553 .enter = &intel_idle,
554 .enter_s2idle = intel_idle_s2idle, },
557 .desc = "MWAIT 0x20",
558 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
560 .target_residency = 700,
561 .enter = &intel_idle,
562 .enter_s2idle = intel_idle_s2idle, },
567 static struct cpuidle_state hsw_cstates[] __initdata = {
570 .desc = "MWAIT 0x00",
571 .flags = MWAIT2flg(0x00),
573 .target_residency = 2,
574 .enter = &intel_idle,
575 .enter_s2idle = intel_idle_s2idle, },
578 .desc = "MWAIT 0x01",
579 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
581 .target_residency = 20,
582 .enter = &intel_idle,
583 .enter_s2idle = intel_idle_s2idle, },
586 .desc = "MWAIT 0x10",
587 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
589 .target_residency = 100,
590 .enter = &intel_idle,
591 .enter_s2idle = intel_idle_s2idle, },
594 .desc = "MWAIT 0x20",
595 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
597 .target_residency = 400,
598 .enter = &intel_idle,
599 .enter_s2idle = intel_idle_s2idle, },
602 .desc = "MWAIT 0x32",
603 .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
605 .target_residency = 500,
606 .enter = &intel_idle,
607 .enter_s2idle = intel_idle_s2idle, },
610 .desc = "MWAIT 0x40",
611 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
613 .target_residency = 900,
614 .enter = &intel_idle,
615 .enter_s2idle = intel_idle_s2idle, },
618 .desc = "MWAIT 0x50",
619 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
621 .target_residency = 1800,
622 .enter = &intel_idle,
623 .enter_s2idle = intel_idle_s2idle, },
626 .desc = "MWAIT 0x60",
627 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
628 .exit_latency = 2600,
629 .target_residency = 7700,
630 .enter = &intel_idle,
631 .enter_s2idle = intel_idle_s2idle, },
635 static struct cpuidle_state bdw_cstates[] __initdata = {
638 .desc = "MWAIT 0x00",
639 .flags = MWAIT2flg(0x00),
641 .target_residency = 2,
642 .enter = &intel_idle,
643 .enter_s2idle = intel_idle_s2idle, },
646 .desc = "MWAIT 0x01",
647 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
649 .target_residency = 20,
650 .enter = &intel_idle,
651 .enter_s2idle = intel_idle_s2idle, },
654 .desc = "MWAIT 0x10",
655 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
657 .target_residency = 100,
658 .enter = &intel_idle,
659 .enter_s2idle = intel_idle_s2idle, },
662 .desc = "MWAIT 0x20",
663 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
665 .target_residency = 400,
666 .enter = &intel_idle,
667 .enter_s2idle = intel_idle_s2idle, },
670 .desc = "MWAIT 0x32",
671 .flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
673 .target_residency = 500,
674 .enter = &intel_idle,
675 .enter_s2idle = intel_idle_s2idle, },
678 .desc = "MWAIT 0x40",
679 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
681 .target_residency = 900,
682 .enter = &intel_idle,
683 .enter_s2idle = intel_idle_s2idle, },
686 .desc = "MWAIT 0x50",
687 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
689 .target_residency = 1800,
690 .enter = &intel_idle,
691 .enter_s2idle = intel_idle_s2idle, },
694 .desc = "MWAIT 0x60",
695 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
696 .exit_latency = 2600,
697 .target_residency = 7700,
698 .enter = &intel_idle,
699 .enter_s2idle = intel_idle_s2idle, },
704 static struct cpuidle_state skl_cstates[] __initdata = {
707 .desc = "MWAIT 0x00",
708 .flags = MWAIT2flg(0x00),
710 .target_residency = 2,
711 .enter = &intel_idle,
712 .enter_s2idle = intel_idle_s2idle, },
715 .desc = "MWAIT 0x01",
716 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
718 .target_residency = 20,
719 .enter = &intel_idle,
720 .enter_s2idle = intel_idle_s2idle, },
723 .desc = "MWAIT 0x10",
724 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
726 .target_residency = 100,
727 .enter = &intel_idle,
728 .enter_s2idle = intel_idle_s2idle, },
731 .desc = "MWAIT 0x20",
732 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
734 .target_residency = 200,
735 .enter = &intel_idle,
736 .enter_s2idle = intel_idle_s2idle, },
739 .desc = "MWAIT 0x33",
740 .flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
742 .target_residency = 800,
743 .enter = &intel_idle,
744 .enter_s2idle = intel_idle_s2idle, },
747 .desc = "MWAIT 0x40",
748 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
750 .target_residency = 800,
751 .enter = &intel_idle,
752 .enter_s2idle = intel_idle_s2idle, },
755 .desc = "MWAIT 0x50",
756 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
758 .target_residency = 5000,
759 .enter = &intel_idle,
760 .enter_s2idle = intel_idle_s2idle, },
763 .desc = "MWAIT 0x60",
764 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
766 .target_residency = 5000,
767 .enter = &intel_idle,
768 .enter_s2idle = intel_idle_s2idle, },
773 static struct cpuidle_state skx_cstates[] __initdata = {
776 .desc = "MWAIT 0x00",
777 .flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_IRQ_ENABLE,
779 .target_residency = 2,
780 .enter = &intel_idle,
781 .enter_s2idle = intel_idle_s2idle, },
784 .desc = "MWAIT 0x01",
785 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
787 .target_residency = 20,
788 .enter = &intel_idle,
789 .enter_s2idle = intel_idle_s2idle, },
792 .desc = "MWAIT 0x20",
793 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
795 .target_residency = 600,
796 .enter = &intel_idle,
797 .enter_s2idle = intel_idle_s2idle, },
802 static struct cpuidle_state icx_cstates[] __initdata = {
805 .desc = "MWAIT 0x00",
806 .flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_IRQ_ENABLE,
808 .target_residency = 1,
809 .enter = &intel_idle,
810 .enter_s2idle = intel_idle_s2idle, },
813 .desc = "MWAIT 0x01",
814 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
816 .target_residency = 4,
817 .enter = &intel_idle,
818 .enter_s2idle = intel_idle_s2idle, },
821 .desc = "MWAIT 0x20",
822 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
824 .target_residency = 600,
825 .enter = &intel_idle,
826 .enter_s2idle = intel_idle_s2idle, },
832 * On AlderLake C1 has to be disabled if C1E is enabled, and vice versa.
833 * C1E is enabled only if "C1E promotion" bit is set in MSR_IA32_POWER_CTL.
834 * But in this case there is effectively no C1, because C1 requests are
835 * promoted to C1E. If the "C1E promotion" bit is cleared, then both C1
836 * and C1E requests end up with C1, so there is effectively no C1E.
838 * By default we enable C1E and disable C1 by marking it with
839 * 'CPUIDLE_FLAG_UNUSABLE'.
841 static struct cpuidle_state adl_cstates[] __initdata = {
844 .desc = "MWAIT 0x00",
845 .flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_UNUSABLE,
847 .target_residency = 1,
848 .enter = &intel_idle,
849 .enter_s2idle = intel_idle_s2idle, },
852 .desc = "MWAIT 0x01",
853 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
855 .target_residency = 4,
856 .enter = &intel_idle,
857 .enter_s2idle = intel_idle_s2idle, },
860 .desc = "MWAIT 0x20",
861 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
863 .target_residency = 600,
864 .enter = &intel_idle,
865 .enter_s2idle = intel_idle_s2idle, },
868 .desc = "MWAIT 0x40",
869 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
871 .target_residency = 800,
872 .enter = &intel_idle,
873 .enter_s2idle = intel_idle_s2idle, },
876 .desc = "MWAIT 0x60",
877 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
879 .target_residency = 2000,
880 .enter = &intel_idle,
881 .enter_s2idle = intel_idle_s2idle, },
886 static struct cpuidle_state adl_l_cstates[] __initdata = {
889 .desc = "MWAIT 0x00",
890 .flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_UNUSABLE,
892 .target_residency = 1,
893 .enter = &intel_idle,
894 .enter_s2idle = intel_idle_s2idle, },
897 .desc = "MWAIT 0x01",
898 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
900 .target_residency = 4,
901 .enter = &intel_idle,
902 .enter_s2idle = intel_idle_s2idle, },
905 .desc = "MWAIT 0x20",
906 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
908 .target_residency = 500,
909 .enter = &intel_idle,
910 .enter_s2idle = intel_idle_s2idle, },
913 .desc = "MWAIT 0x40",
914 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
916 .target_residency = 600,
917 .enter = &intel_idle,
918 .enter_s2idle = intel_idle_s2idle, },
921 .desc = "MWAIT 0x60",
922 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
924 .target_residency = 700,
925 .enter = &intel_idle,
926 .enter_s2idle = intel_idle_s2idle, },
931 static struct cpuidle_state spr_cstates[] __initdata = {
934 .desc = "MWAIT 0x00",
935 .flags = MWAIT2flg(0x00),
937 .target_residency = 1,
938 .enter = &intel_idle,
939 .enter_s2idle = intel_idle_s2idle, },
942 .desc = "MWAIT 0x01",
943 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
945 .target_residency = 4,
946 .enter = &intel_idle,
947 .enter_s2idle = intel_idle_s2idle, },
950 .desc = "MWAIT 0x20",
951 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED |
952 CPUIDLE_FLAG_INIT_XSTATE,
954 .target_residency = 800,
955 .enter = &intel_idle,
956 .enter_s2idle = intel_idle_s2idle, },
961 static struct cpuidle_state atom_cstates[] __initdata = {
964 .desc = "MWAIT 0x00",
965 .flags = MWAIT2flg(0x00),
967 .target_residency = 20,
968 .enter = &intel_idle,
969 .enter_s2idle = intel_idle_s2idle, },
972 .desc = "MWAIT 0x10",
973 .flags = MWAIT2flg(0x10),
975 .target_residency = 80,
976 .enter = &intel_idle,
977 .enter_s2idle = intel_idle_s2idle, },
980 .desc = "MWAIT 0x30",
981 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
983 .target_residency = 400,
984 .enter = &intel_idle,
985 .enter_s2idle = intel_idle_s2idle, },
988 .desc = "MWAIT 0x52",
989 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
991 .target_residency = 560,
992 .enter = &intel_idle,
993 .enter_s2idle = intel_idle_s2idle, },
997 static struct cpuidle_state tangier_cstates[] __initdata = {
1000 .desc = "MWAIT 0x00",
1001 .flags = MWAIT2flg(0x00),
1003 .target_residency = 4,
1004 .enter = &intel_idle,
1005 .enter_s2idle = intel_idle_s2idle, },
1008 .desc = "MWAIT 0x30",
1009 .flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
1010 .exit_latency = 100,
1011 .target_residency = 400,
1012 .enter = &intel_idle,
1013 .enter_s2idle = intel_idle_s2idle, },
1016 .desc = "MWAIT 0x52",
1017 .flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
1018 .exit_latency = 140,
1019 .target_residency = 560,
1020 .enter = &intel_idle,
1021 .enter_s2idle = intel_idle_s2idle, },
1024 .desc = "MWAIT 0x60",
1025 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
1026 .exit_latency = 1200,
1027 .target_residency = 4000,
1028 .enter = &intel_idle,
1029 .enter_s2idle = intel_idle_s2idle, },
1032 .desc = "MWAIT 0x64",
1033 .flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
1034 .exit_latency = 10000,
1035 .target_residency = 20000,
1036 .enter = &intel_idle,
1037 .enter_s2idle = intel_idle_s2idle, },
1041 static struct cpuidle_state avn_cstates[] __initdata = {
1044 .desc = "MWAIT 0x00",
1045 .flags = MWAIT2flg(0x00),
1047 .target_residency = 2,
1048 .enter = &intel_idle,
1049 .enter_s2idle = intel_idle_s2idle, },
1052 .desc = "MWAIT 0x51",
1053 .flags = MWAIT2flg(0x51) | CPUIDLE_FLAG_TLB_FLUSHED,
1055 .target_residency = 45,
1056 .enter = &intel_idle,
1057 .enter_s2idle = intel_idle_s2idle, },
1061 static struct cpuidle_state knl_cstates[] __initdata = {
1064 .desc = "MWAIT 0x00",
1065 .flags = MWAIT2flg(0x00),
1067 .target_residency = 2,
1068 .enter = &intel_idle,
1069 .enter_s2idle = intel_idle_s2idle },
1072 .desc = "MWAIT 0x10",
1073 .flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
1074 .exit_latency = 120,
1075 .target_residency = 500,
1076 .enter = &intel_idle,
1077 .enter_s2idle = intel_idle_s2idle },
1082 static struct cpuidle_state bxt_cstates[] __initdata = {
1085 .desc = "MWAIT 0x00",
1086 .flags = MWAIT2flg(0x00),
1088 .target_residency = 2,
1089 .enter = &intel_idle,
1090 .enter_s2idle = intel_idle_s2idle, },
1093 .desc = "MWAIT 0x01",
1094 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1096 .target_residency = 20,
1097 .enter = &intel_idle,
1098 .enter_s2idle = intel_idle_s2idle, },
1101 .desc = "MWAIT 0x20",
1102 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
1103 .exit_latency = 133,
1104 .target_residency = 133,
1105 .enter = &intel_idle,
1106 .enter_s2idle = intel_idle_s2idle, },
1109 .desc = "MWAIT 0x31",
1110 .flags = MWAIT2flg(0x31) | CPUIDLE_FLAG_TLB_FLUSHED,
1111 .exit_latency = 155,
1112 .target_residency = 155,
1113 .enter = &intel_idle,
1114 .enter_s2idle = intel_idle_s2idle, },
1117 .desc = "MWAIT 0x40",
1118 .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
1119 .exit_latency = 1000,
1120 .target_residency = 1000,
1121 .enter = &intel_idle,
1122 .enter_s2idle = intel_idle_s2idle, },
1125 .desc = "MWAIT 0x50",
1126 .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
1127 .exit_latency = 2000,
1128 .target_residency = 2000,
1129 .enter = &intel_idle,
1130 .enter_s2idle = intel_idle_s2idle, },
1133 .desc = "MWAIT 0x60",
1134 .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
1135 .exit_latency = 10000,
1136 .target_residency = 10000,
1137 .enter = &intel_idle,
1138 .enter_s2idle = intel_idle_s2idle, },
1143 static struct cpuidle_state dnv_cstates[] __initdata = {
1146 .desc = "MWAIT 0x00",
1147 .flags = MWAIT2flg(0x00),
1149 .target_residency = 2,
1150 .enter = &intel_idle,
1151 .enter_s2idle = intel_idle_s2idle, },
1154 .desc = "MWAIT 0x01",
1155 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1157 .target_residency = 20,
1158 .enter = &intel_idle,
1159 .enter_s2idle = intel_idle_s2idle, },
1162 .desc = "MWAIT 0x20",
1163 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
1165 .target_residency = 500,
1166 .enter = &intel_idle,
1167 .enter_s2idle = intel_idle_s2idle, },
1173 * Note, depending on HW and FW revision, SnowRidge SoC may or may not support
1174 * C6, and this is indicated in the CPUID mwait leaf.
1176 static struct cpuidle_state snr_cstates[] __initdata = {
1179 .desc = "MWAIT 0x00",
1180 .flags = MWAIT2flg(0x00),
1182 .target_residency = 2,
1183 .enter = &intel_idle,
1184 .enter_s2idle = intel_idle_s2idle, },
1187 .desc = "MWAIT 0x01",
1188 .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1190 .target_residency = 25,
1191 .enter = &intel_idle,
1192 .enter_s2idle = intel_idle_s2idle, },
1195 .desc = "MWAIT 0x20",
1196 .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
1197 .exit_latency = 130,
1198 .target_residency = 500,
1199 .enter = &intel_idle,
1200 .enter_s2idle = intel_idle_s2idle, },
1205 static const struct idle_cpu idle_cpu_nehalem __initconst = {
1206 .state_table = nehalem_cstates,
1207 .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
1208 .disable_promotion_to_c1e = true,
1211 static const struct idle_cpu idle_cpu_nhx __initconst = {
1212 .state_table = nehalem_cstates,
1213 .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
1214 .disable_promotion_to_c1e = true,
1218 static const struct idle_cpu idle_cpu_atom __initconst = {
1219 .state_table = atom_cstates,
1222 static const struct idle_cpu idle_cpu_tangier __initconst = {
1223 .state_table = tangier_cstates,
1226 static const struct idle_cpu idle_cpu_lincroft __initconst = {
1227 .state_table = atom_cstates,
1228 .auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE,
1231 static const struct idle_cpu idle_cpu_snb __initconst = {
1232 .state_table = snb_cstates,
1233 .disable_promotion_to_c1e = true,
1236 static const struct idle_cpu idle_cpu_snx __initconst = {
1237 .state_table = snb_cstates,
1238 .disable_promotion_to_c1e = true,
1242 static const struct idle_cpu idle_cpu_byt __initconst = {
1243 .state_table = byt_cstates,
1244 .disable_promotion_to_c1e = true,
1245 .byt_auto_demotion_disable_flag = true,
1248 static const struct idle_cpu idle_cpu_cht __initconst = {
1249 .state_table = cht_cstates,
1250 .disable_promotion_to_c1e = true,
1251 .byt_auto_demotion_disable_flag = true,
1254 static const struct idle_cpu idle_cpu_ivb __initconst = {
1255 .state_table = ivb_cstates,
1256 .disable_promotion_to_c1e = true,
1259 static const struct idle_cpu idle_cpu_ivt __initconst = {
1260 .state_table = ivt_cstates,
1261 .disable_promotion_to_c1e = true,
1265 static const struct idle_cpu idle_cpu_hsw __initconst = {
1266 .state_table = hsw_cstates,
1267 .disable_promotion_to_c1e = true,
1270 static const struct idle_cpu idle_cpu_hsx __initconst = {
1271 .state_table = hsw_cstates,
1272 .disable_promotion_to_c1e = true,
1276 static const struct idle_cpu idle_cpu_bdw __initconst = {
1277 .state_table = bdw_cstates,
1278 .disable_promotion_to_c1e = true,
1281 static const struct idle_cpu idle_cpu_bdx __initconst = {
1282 .state_table = bdw_cstates,
1283 .disable_promotion_to_c1e = true,
1287 static const struct idle_cpu idle_cpu_skl __initconst = {
1288 .state_table = skl_cstates,
1289 .disable_promotion_to_c1e = true,
1292 static const struct idle_cpu idle_cpu_skx __initconst = {
1293 .state_table = skx_cstates,
1294 .disable_promotion_to_c1e = true,
1298 static const struct idle_cpu idle_cpu_icx __initconst = {
1299 .state_table = icx_cstates,
1300 .disable_promotion_to_c1e = true,
1304 static const struct idle_cpu idle_cpu_adl __initconst = {
1305 .state_table = adl_cstates,
1308 static const struct idle_cpu idle_cpu_adl_l __initconst = {
1309 .state_table = adl_l_cstates,
1312 static const struct idle_cpu idle_cpu_spr __initconst = {
1313 .state_table = spr_cstates,
1314 .disable_promotion_to_c1e = true,
1318 static const struct idle_cpu idle_cpu_avn __initconst = {
1319 .state_table = avn_cstates,
1320 .disable_promotion_to_c1e = true,
1324 static const struct idle_cpu idle_cpu_knl __initconst = {
1325 .state_table = knl_cstates,
1329 static const struct idle_cpu idle_cpu_bxt __initconst = {
1330 .state_table = bxt_cstates,
1331 .disable_promotion_to_c1e = true,
1334 static const struct idle_cpu idle_cpu_dnv __initconst = {
1335 .state_table = dnv_cstates,
1336 .disable_promotion_to_c1e = true,
1340 static const struct idle_cpu idle_cpu_snr __initconst = {
1341 .state_table = snr_cstates,
1342 .disable_promotion_to_c1e = true,
1346 static const struct x86_cpu_id intel_idle_ids[] __initconst = {
1347 X86_MATCH_INTEL_FAM6_MODEL(NEHALEM_EP, &idle_cpu_nhx),
1348 X86_MATCH_INTEL_FAM6_MODEL(NEHALEM, &idle_cpu_nehalem),
1349 X86_MATCH_INTEL_FAM6_MODEL(NEHALEM_G, &idle_cpu_nehalem),
1350 X86_MATCH_INTEL_FAM6_MODEL(WESTMERE, &idle_cpu_nehalem),
1351 X86_MATCH_INTEL_FAM6_MODEL(WESTMERE_EP, &idle_cpu_nhx),
1352 X86_MATCH_INTEL_FAM6_MODEL(NEHALEM_EX, &idle_cpu_nhx),
1353 X86_MATCH_INTEL_FAM6_MODEL(ATOM_BONNELL, &idle_cpu_atom),
1354 X86_MATCH_INTEL_FAM6_MODEL(ATOM_BONNELL_MID, &idle_cpu_lincroft),
1355 X86_MATCH_INTEL_FAM6_MODEL(WESTMERE_EX, &idle_cpu_nhx),
1356 X86_MATCH_INTEL_FAM6_MODEL(SANDYBRIDGE, &idle_cpu_snb),
1357 X86_MATCH_INTEL_FAM6_MODEL(SANDYBRIDGE_X, &idle_cpu_snx),
1358 X86_MATCH_INTEL_FAM6_MODEL(ATOM_SALTWELL, &idle_cpu_atom),
1359 X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT, &idle_cpu_byt),
1360 X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_MID, &idle_cpu_tangier),
1361 X86_MATCH_INTEL_FAM6_MODEL(ATOM_AIRMONT, &idle_cpu_cht),
1362 X86_MATCH_INTEL_FAM6_MODEL(IVYBRIDGE, &idle_cpu_ivb),
1363 X86_MATCH_INTEL_FAM6_MODEL(IVYBRIDGE_X, &idle_cpu_ivt),
1364 X86_MATCH_INTEL_FAM6_MODEL(HASWELL, &idle_cpu_hsw),
1365 X86_MATCH_INTEL_FAM6_MODEL(HASWELL_X, &idle_cpu_hsx),
1366 X86_MATCH_INTEL_FAM6_MODEL(HASWELL_L, &idle_cpu_hsw),
1367 X86_MATCH_INTEL_FAM6_MODEL(HASWELL_G, &idle_cpu_hsw),
1368 X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT_D, &idle_cpu_avn),
1369 X86_MATCH_INTEL_FAM6_MODEL(BROADWELL, &idle_cpu_bdw),
1370 X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_G, &idle_cpu_bdw),
1371 X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_X, &idle_cpu_bdx),
1372 X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_D, &idle_cpu_bdx),
1373 X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_L, &idle_cpu_skl),
1374 X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE, &idle_cpu_skl),
1375 X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE_L, &idle_cpu_skl),
1376 X86_MATCH_INTEL_FAM6_MODEL(KABYLAKE, &idle_cpu_skl),
1377 X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_X, &idle_cpu_skx),
1378 X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X, &idle_cpu_icx),
1379 X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D, &idle_cpu_icx),
1380 X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE, &idle_cpu_adl),
1381 X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE_L, &idle_cpu_adl_l),
1382 X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X, &idle_cpu_spr),
1383 X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNL, &idle_cpu_knl),
1384 X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNM, &idle_cpu_knl),
1385 X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT, &idle_cpu_bxt),
1386 X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_PLUS, &idle_cpu_bxt),
1387 X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT_D, &idle_cpu_dnv),
1388 X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_D, &idle_cpu_snr),
1392 static const struct x86_cpu_id intel_mwait_ids[] __initconst = {
1393 X86_MATCH_VENDOR_FAM_FEATURE(INTEL, 6, X86_FEATURE_MWAIT, NULL),
1397 static bool __init intel_idle_max_cstate_reached(int cstate)
1399 if (cstate + 1 > max_cstate) {
1400 pr_info("max_cstate %d reached\n", max_cstate);
1406 static bool __init intel_idle_state_needs_timer_stop(struct cpuidle_state *state)
1408 unsigned long eax = flg2MWAIT(state->flags);
1410 if (boot_cpu_has(X86_FEATURE_ARAT))
1414 * Switch over to one-shot tick broadcast if the target C-state
1415 * is deeper than C1.
1417 return !!((eax >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK);
1420 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
1421 #include <acpi/processor.h>
1423 static bool no_acpi __read_mostly;
1424 module_param(no_acpi, bool, 0444);
1425 MODULE_PARM_DESC(no_acpi, "Do not use ACPI _CST for building the idle states list");
1427 static bool force_use_acpi __read_mostly; /* No effect if no_acpi is set. */
1428 module_param_named(use_acpi, force_use_acpi, bool, 0444);
1429 MODULE_PARM_DESC(use_acpi, "Use ACPI _CST for building the idle states list");
1431 static struct acpi_processor_power acpi_state_table __initdata;
1434 * intel_idle_cst_usable - Check if the _CST information can be used.
1436 * Check if all of the C-states listed by _CST in the max_cstate range are
1437 * ACPI_CSTATE_FFH, which means that they should be entered via MWAIT.
1439 static bool __init intel_idle_cst_usable(void)
1443 limit = min_t(int, min_t(int, CPUIDLE_STATE_MAX, max_cstate + 1),
1444 acpi_state_table.count);
1446 for (cstate = 1; cstate < limit; cstate++) {
1447 struct acpi_processor_cx *cx = &acpi_state_table.states[cstate];
1449 if (cx->entry_method != ACPI_CSTATE_FFH)
1456 static bool __init intel_idle_acpi_cst_extract(void)
1461 pr_debug("Not allowed to use ACPI _CST\n");
1465 for_each_possible_cpu(cpu) {
1466 struct acpi_processor *pr = per_cpu(processors, cpu);
1471 if (acpi_processor_evaluate_cst(pr->handle, cpu, &acpi_state_table))
1474 acpi_state_table.count++;
1476 if (!intel_idle_cst_usable())
1479 if (!acpi_processor_claim_cst_control())
1485 acpi_state_table.count = 0;
1486 pr_debug("ACPI _CST not found or not usable\n");
1490 static void __init intel_idle_init_cstates_acpi(struct cpuidle_driver *drv)
1492 int cstate, limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1495 * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1496 * the interesting states are ACPI_CSTATE_FFH.
1498 for (cstate = 1; cstate < limit; cstate++) {
1499 struct acpi_processor_cx *cx;
1500 struct cpuidle_state *state;
1502 if (intel_idle_max_cstate_reached(cstate - 1))
1505 cx = &acpi_state_table.states[cstate];
1507 state = &drv->states[drv->state_count++];
1509 snprintf(state->name, CPUIDLE_NAME_LEN, "C%d_ACPI", cstate);
1510 strlcpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
1511 state->exit_latency = cx->latency;
1513 * For C1-type C-states use the same number for both the exit
1514 * latency and target residency, because that is the case for
1515 * C1 in the majority of the static C-states tables above.
1516 * For the other types of C-states, however, set the target
1517 * residency to 3 times the exit latency which should lead to
1518 * a reasonable balance between energy-efficiency and
1519 * performance in the majority of interesting cases.
1521 state->target_residency = cx->latency;
1522 if (cx->type > ACPI_STATE_C1)
1523 state->target_residency *= 3;
1525 state->flags = MWAIT2flg(cx->address);
1526 if (cx->type > ACPI_STATE_C2)
1527 state->flags |= CPUIDLE_FLAG_TLB_FLUSHED;
1529 if (disabled_states_mask & BIT(cstate))
1530 state->flags |= CPUIDLE_FLAG_OFF;
1532 if (intel_idle_state_needs_timer_stop(state))
1533 state->flags |= CPUIDLE_FLAG_TIMER_STOP;
1535 state->enter = intel_idle;
1536 state->enter_s2idle = intel_idle_s2idle;
1540 static bool __init intel_idle_off_by_default(u32 mwait_hint)
1545 * If there are no _CST C-states, do not disable any C-states by
1548 if (!acpi_state_table.count)
1551 limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1553 * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1554 * the interesting states are ACPI_CSTATE_FFH.
1556 for (cstate = 1; cstate < limit; cstate++) {
1557 if (acpi_state_table.states[cstate].address == mwait_hint)
1562 #else /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1563 #define force_use_acpi (false)
1565 static inline bool intel_idle_acpi_cst_extract(void) { return false; }
1566 static inline void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { }
1567 static inline bool intel_idle_off_by_default(u32 mwait_hint) { return false; }
1568 #endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1571 * ivt_idle_state_table_update - Tune the idle states table for Ivy Town.
1573 * Tune IVT multi-socket targets.
1574 * Assumption: num_sockets == (max_package_num + 1).
1576 static void __init ivt_idle_state_table_update(void)
1578 /* IVT uses a different table for 1-2, 3-4, and > 4 sockets */
1579 int cpu, package_num, num_sockets = 1;
1581 for_each_online_cpu(cpu) {
1582 package_num = topology_physical_package_id(cpu);
1583 if (package_num + 1 > num_sockets) {
1584 num_sockets = package_num + 1;
1586 if (num_sockets > 4) {
1587 cpuidle_state_table = ivt_cstates_8s;
1593 if (num_sockets > 2)
1594 cpuidle_state_table = ivt_cstates_4s;
1596 /* else, 1 and 2 socket systems use default ivt_cstates */
1600 * irtl_2_usec - IRTL to microseconds conversion.
1601 * @irtl: IRTL MSR value.
1603 * Translate the IRTL (Interrupt Response Time Limit) MSR value to microseconds.
1605 static unsigned long long __init irtl_2_usec(unsigned long long irtl)
1607 static const unsigned int irtl_ns_units[] __initconst = {
1608 1, 32, 1024, 32768, 1048576, 33554432, 0, 0
1610 unsigned long long ns;
1615 ns = irtl_ns_units[(irtl >> 10) & 0x7];
1617 return div_u64((irtl & 0x3FF) * ns, NSEC_PER_USEC);
1621 * bxt_idle_state_table_update - Fix up the Broxton idle states table.
1623 * On BXT, trust the IRTL (Interrupt Response Time Limit) MSR to show the
1624 * definitive maximum latency and use the same value for target_residency.
1626 static void __init bxt_idle_state_table_update(void)
1628 unsigned long long msr;
1631 rdmsrl(MSR_PKGC6_IRTL, msr);
1632 usec = irtl_2_usec(msr);
1634 bxt_cstates[2].exit_latency = usec;
1635 bxt_cstates[2].target_residency = usec;
1638 rdmsrl(MSR_PKGC7_IRTL, msr);
1639 usec = irtl_2_usec(msr);
1641 bxt_cstates[3].exit_latency = usec;
1642 bxt_cstates[3].target_residency = usec;
1645 rdmsrl(MSR_PKGC8_IRTL, msr);
1646 usec = irtl_2_usec(msr);
1648 bxt_cstates[4].exit_latency = usec;
1649 bxt_cstates[4].target_residency = usec;
1652 rdmsrl(MSR_PKGC9_IRTL, msr);
1653 usec = irtl_2_usec(msr);
1655 bxt_cstates[5].exit_latency = usec;
1656 bxt_cstates[5].target_residency = usec;
1659 rdmsrl(MSR_PKGC10_IRTL, msr);
1660 usec = irtl_2_usec(msr);
1662 bxt_cstates[6].exit_latency = usec;
1663 bxt_cstates[6].target_residency = usec;
1669 * sklh_idle_state_table_update - Fix up the Sky Lake idle states table.
1671 * On SKL-H (model 0x5e) skip C8 and C9 if C10 is enabled and SGX disabled.
1673 static void __init sklh_idle_state_table_update(void)
1675 unsigned long long msr;
1676 unsigned int eax, ebx, ecx, edx;
1679 /* if PC10 disabled via cmdline intel_idle.max_cstate=7 or shallower */
1680 if (max_cstate <= 7)
1683 /* if PC10 not present in CPUID.MWAIT.EDX */
1684 if ((mwait_substates & (0xF << 28)) == 0)
1687 rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr);
1689 /* PC10 is not enabled in PKG C-state limit */
1690 if ((msr & 0xF) != 8)
1694 cpuid(7, &eax, &ebx, &ecx, &edx);
1696 /* if SGX is present */
1697 if (ebx & (1 << 2)) {
1699 rdmsrl(MSR_IA32_FEAT_CTL, msr);
1701 /* if SGX is enabled */
1702 if (msr & (1 << 18))
1706 skl_cstates[5].flags |= CPUIDLE_FLAG_UNUSABLE; /* C8-SKL */
1707 skl_cstates[6].flags |= CPUIDLE_FLAG_UNUSABLE; /* C9-SKL */
1711 * skx_idle_state_table_update - Adjust the Sky Lake/Cascade Lake
1712 * idle states table.
1714 static void __init skx_idle_state_table_update(void)
1716 unsigned long long msr;
1718 rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr);
1721 * 000b: C0/C1 (no package C-state support)
1723 * 010b: C6 (non-retention)
1724 * 011b: C6 (retention)
1725 * 111b: No Package C state limits.
1727 if ((msr & 0x7) < 2) {
1729 * Uses the CC6 + PC0 latency and 3 times of
1730 * latency for target_residency if the PC6
1731 * is disabled in BIOS. This is consistent
1732 * with how intel_idle driver uses _CST
1733 * to set the target_residency.
1735 skx_cstates[2].exit_latency = 92;
1736 skx_cstates[2].target_residency = 276;
1741 * adl_idle_state_table_update - Adjust AlderLake idle states table.
1743 static void __init adl_idle_state_table_update(void)
1745 /* Check if user prefers C1 over C1E. */
1746 if (preferred_states_mask & BIT(1) && !(preferred_states_mask & BIT(2))) {
1747 cpuidle_state_table[0].flags &= ~CPUIDLE_FLAG_UNUSABLE;
1748 cpuidle_state_table[1].flags |= CPUIDLE_FLAG_UNUSABLE;
1750 /* Disable C1E by clearing the "C1E promotion" bit. */
1751 c1e_promotion = C1E_PROMOTION_DISABLE;
1755 /* Make sure C1E is enabled by default */
1756 c1e_promotion = C1E_PROMOTION_ENABLE;
1760 * spr_idle_state_table_update - Adjust Sapphire Rapids idle states table.
1762 static void __init spr_idle_state_table_update(void)
1764 unsigned long long msr;
1767 * By default, the C6 state assumes the worst-case scenario of package
1768 * C6. However, if PC6 is disabled, we update the numbers to match
1771 rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr);
1773 /* Limit value 2 and above allow for PC6. */
1774 if ((msr & 0x7) < 2) {
1775 spr_cstates[2].exit_latency = 190;
1776 spr_cstates[2].target_residency = 600;
1780 static bool __init intel_idle_verify_cstate(unsigned int mwait_hint)
1782 unsigned int mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint) + 1;
1783 unsigned int num_substates = (mwait_substates >> mwait_cstate * 4) &
1784 MWAIT_SUBSTATE_MASK;
1786 /* Ignore the C-state if there are NO sub-states in CPUID for it. */
1787 if (num_substates == 0)
1790 if (mwait_cstate > 2 && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
1791 mark_tsc_unstable("TSC halts in idle states deeper than C2");
1796 static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
1800 switch (boot_cpu_data.x86_model) {
1801 case INTEL_FAM6_IVYBRIDGE_X:
1802 ivt_idle_state_table_update();
1804 case INTEL_FAM6_ATOM_GOLDMONT:
1805 case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
1806 bxt_idle_state_table_update();
1808 case INTEL_FAM6_SKYLAKE:
1809 sklh_idle_state_table_update();
1811 case INTEL_FAM6_SKYLAKE_X:
1812 skx_idle_state_table_update();
1814 case INTEL_FAM6_SAPPHIRERAPIDS_X:
1815 spr_idle_state_table_update();
1817 case INTEL_FAM6_ALDERLAKE:
1818 case INTEL_FAM6_ALDERLAKE_L:
1819 adl_idle_state_table_update();
1823 for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
1824 unsigned int mwait_hint;
1826 if (intel_idle_max_cstate_reached(cstate))
1829 if (!cpuidle_state_table[cstate].enter &&
1830 !cpuidle_state_table[cstate].enter_s2idle)
1833 /* If marked as unusable, skip this state. */
1834 if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_UNUSABLE) {
1835 pr_debug("state %s is disabled\n",
1836 cpuidle_state_table[cstate].name);
1840 mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags);
1841 if (!intel_idle_verify_cstate(mwait_hint))
1844 /* Structure copy. */
1845 drv->states[drv->state_count] = cpuidle_state_table[cstate];
1847 if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_IRQ_ENABLE)
1848 drv->states[drv->state_count].enter = intel_idle_irq;
1850 if (cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS) &&
1851 cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_IBRS) {
1852 WARN_ON_ONCE(cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_IRQ_ENABLE);
1853 drv->states[drv->state_count].enter = intel_idle_ibrs;
1856 if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_INIT_XSTATE)
1857 drv->states[drv->state_count].enter = intel_idle_xstate;
1859 if ((disabled_states_mask & BIT(drv->state_count)) ||
1860 ((icpu->use_acpi || force_use_acpi) &&
1861 intel_idle_off_by_default(mwait_hint) &&
1862 !(cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_ALWAYS_ENABLE)))
1863 drv->states[drv->state_count].flags |= CPUIDLE_FLAG_OFF;
1865 if (intel_idle_state_needs_timer_stop(&drv->states[drv->state_count]))
1866 drv->states[drv->state_count].flags |= CPUIDLE_FLAG_TIMER_STOP;
1871 if (icpu->byt_auto_demotion_disable_flag) {
1872 wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
1873 wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
1878 * intel_idle_cpuidle_driver_init - Create the list of available idle states.
1879 * @drv: cpuidle driver structure to initialize.
1881 static void __init intel_idle_cpuidle_driver_init(struct cpuidle_driver *drv)
1883 cpuidle_poll_state_init(drv);
1885 if (disabled_states_mask & BIT(0))
1886 drv->states[0].flags |= CPUIDLE_FLAG_OFF;
1888 drv->state_count = 1;
1891 intel_idle_init_cstates_icpu(drv);
1893 intel_idle_init_cstates_acpi(drv);
1896 static void auto_demotion_disable(void)
1898 unsigned long long msr_bits;
1900 rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
1901 msr_bits &= ~auto_demotion_disable_flags;
1902 wrmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
1905 static void c1e_promotion_enable(void)
1907 unsigned long long msr_bits;
1909 rdmsrl(MSR_IA32_POWER_CTL, msr_bits);
1911 wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
1914 static void c1e_promotion_disable(void)
1916 unsigned long long msr_bits;
1918 rdmsrl(MSR_IA32_POWER_CTL, msr_bits);
1920 wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
1924 * intel_idle_cpu_init - Register the target CPU with the cpuidle core.
1925 * @cpu: CPU to initialize.
1927 * Register a cpuidle device object for @cpu and update its MSRs in accordance
1928 * with the processor model flags.
1930 static int intel_idle_cpu_init(unsigned int cpu)
1932 struct cpuidle_device *dev;
1934 dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
1937 if (cpuidle_register_device(dev)) {
1938 pr_debug("cpuidle_register_device %d failed!\n", cpu);
1942 if (auto_demotion_disable_flags)
1943 auto_demotion_disable();
1945 if (c1e_promotion == C1E_PROMOTION_ENABLE)
1946 c1e_promotion_enable();
1947 else if (c1e_promotion == C1E_PROMOTION_DISABLE)
1948 c1e_promotion_disable();
1953 static int intel_idle_cpu_online(unsigned int cpu)
1955 struct cpuidle_device *dev;
1957 if (!boot_cpu_has(X86_FEATURE_ARAT))
1958 tick_broadcast_enable();
1961 * Some systems can hotplug a cpu at runtime after
1962 * the kernel has booted, we have to initialize the
1963 * driver in this case
1965 dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
1966 if (!dev->registered)
1967 return intel_idle_cpu_init(cpu);
1973 * intel_idle_cpuidle_devices_uninit - Unregister all cpuidle devices.
1975 static void __init intel_idle_cpuidle_devices_uninit(void)
1979 for_each_online_cpu(i)
1980 cpuidle_unregister_device(per_cpu_ptr(intel_idle_cpuidle_devices, i));
1983 static int __init intel_idle_init(void)
1985 const struct x86_cpu_id *id;
1986 unsigned int eax, ebx, ecx;
1989 /* Do not load intel_idle at all for now if idle= is passed */
1990 if (boot_option_idle_override != IDLE_NO_OVERRIDE)
1993 if (max_cstate == 0) {
1994 pr_debug("disabled\n");
1998 id = x86_match_cpu(intel_idle_ids);
2000 if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
2001 pr_debug("Please enable MWAIT in BIOS SETUP\n");
2005 id = x86_match_cpu(intel_mwait_ids);
2010 if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
2013 cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates);
2015 if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
2016 !(ecx & CPUID5_ECX_INTERRUPT_BREAK) ||
2020 pr_debug("MWAIT substates: 0x%x\n", mwait_substates);
2022 icpu = (const struct idle_cpu *)id->driver_data;
2024 cpuidle_state_table = icpu->state_table;
2025 auto_demotion_disable_flags = icpu->auto_demotion_disable_flags;
2026 if (icpu->disable_promotion_to_c1e)
2027 c1e_promotion = C1E_PROMOTION_DISABLE;
2028 if (icpu->use_acpi || force_use_acpi)
2029 intel_idle_acpi_cst_extract();
2030 } else if (!intel_idle_acpi_cst_extract()) {
2034 pr_debug("v" INTEL_IDLE_VERSION " model 0x%X\n",
2035 boot_cpu_data.x86_model);
2037 intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
2038 if (!intel_idle_cpuidle_devices)
2041 intel_idle_cpuidle_driver_init(&intel_idle_driver);
2043 retval = cpuidle_register_driver(&intel_idle_driver);
2045 struct cpuidle_driver *drv = cpuidle_get_driver();
2046 printk(KERN_DEBUG pr_fmt("intel_idle yielding to %s\n"),
2047 drv ? drv->name : "none");
2048 goto init_driver_fail;
2051 retval = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "idle/intel:online",
2052 intel_idle_cpu_online, NULL);
2056 pr_debug("Local APIC timer is reliable in %s\n",
2057 boot_cpu_has(X86_FEATURE_ARAT) ? "all C-states" : "C1");
2062 intel_idle_cpuidle_devices_uninit();
2063 cpuidle_unregister_driver(&intel_idle_driver);
2065 free_percpu(intel_idle_cpuidle_devices);
2069 device_initcall(intel_idle_init);
2072 * We are not really modular, but we used to support that. Meaning we also
2073 * support "intel_idle.max_cstate=..." at boot and also a read-only export of
2074 * it at /sys/module/intel_idle/parameters/max_cstate -- so using module_param
2075 * is the easiest way (currently) to continue doing that.
2077 module_param(max_cstate, int, 0444);
2079 * The positions of the bits that are set in this number are the indices of the
2080 * idle states to be disabled by default (as reflected by the names of the
2081 * corresponding idle state directories in sysfs, "state0", "state1" ...
2082 * "state<i>" ..., where <i> is the index of the given state).
2084 module_param_named(states_off, disabled_states_mask, uint, 0444);
2085 MODULE_PARM_DESC(states_off, "Mask of disabled idle states");
2087 * Some platforms come with mutually exclusive C-states, so that if one is
2088 * enabled, the other C-states must not be used. Example: C1 and C1E on
2089 * Sapphire Rapids platform. This parameter allows for selecting the
2090 * preferred C-states among the groups of mutually exclusive C-states - the
2091 * selected C-states will be registered, the other C-states from the mutually
2092 * exclusive group won't be registered. If the platform has no mutually
2093 * exclusive C-states, this parameter has no effect.
2095 module_param_named(preferred_cstates, preferred_states_mask, uint, 0444);
2096 MODULE_PARM_DESC(preferred_cstates, "Mask of preferred idle states");