xref: /linux/drivers/idle/intel_idle.c (revision 69050f8d6d075dc01af7a5f2f550a8067510366f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * intel_idle.c - native hardware idle loop for modern Intel processors
4  *
5  * Copyright (c) 2013 - 2020, Intel Corporation.
6  * Len Brown <len.brown@intel.com>
7  * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8  */
9 
10 /*
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.
15  */
16 
17 /*
18  * Design Assumptions
19  *
20  * All CPUs have same idle states as boot CPU
21  *
22  * Chipset BM_STS (bus master status) bit is a NOP
23  *	for preventing entry into deep C-states
24  *
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)
28  */
29 
30 /*
31  * Known limitations
32  *
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.
36  *
37  */
38 
39 /* un-comment DEBUG to enable pr_debug() statements */
40 /* #define DEBUG */
41 
42 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
43 
44 #include <linux/acpi.h>
45 #include <linux/kernel.h>
46 #include <linux/cpuidle.h>
47 #include <linux/tick.h>
48 #include <linux/time64.h>
49 #include <trace/events/power.h>
50 #include <linux/sched.h>
51 #include <linux/sched/smt.h>
52 #include <linux/mutex.h>
53 #include <linux/notifier.h>
54 #include <linux/cpu.h>
55 #include <linux/moduleparam.h>
56 #include <linux/sysfs.h>
57 #include <asm/cpuid/api.h>
58 #include <asm/cpu_device_id.h>
59 #include <asm/intel-family.h>
60 #include <asm/mwait.h>
61 #include <asm/spec-ctrl.h>
62 #include <asm/msr.h>
63 #include <asm/tsc.h>
64 #include <asm/fpu/api.h>
65 #include <asm/smp.h>
66 
67 static struct cpuidle_driver intel_idle_driver = {
68 	.name = "intel_idle",
69 	.owner = THIS_MODULE,
70 };
71 /* intel_idle.max_cstate=0 disables driver */
72 static int max_cstate = CPUIDLE_STATE_MAX - 1;
73 static unsigned int disabled_states_mask __read_mostly;
74 static bool force_irq_on __read_mostly;
75 static bool ibrs_off __read_mostly;
76 
77 /* The maximum allowed length for the 'table' module parameter  */
78 #define MAX_CMDLINE_TABLE_LEN 256
79 /* Maximum allowed C-state latency */
80 #define MAX_CMDLINE_LATENCY_US (5 * USEC_PER_MSEC)
81 /* Maximum allowed C-state target residency */
82 #define MAX_CMDLINE_RESIDENCY_US (100 * USEC_PER_MSEC)
83 
84 static char cmdline_table_str[MAX_CMDLINE_TABLE_LEN] __read_mostly;
85 
86 static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
87 
88 static unsigned long auto_demotion_disable_flags;
89 
90 static enum {
91 	C1E_PROMOTION_PRESERVE,
92 	C1E_PROMOTION_ENABLE,
93 	C1E_PROMOTION_DISABLE
94 } c1e_promotion = C1E_PROMOTION_PRESERVE;
95 
96 struct idle_cpu {
97 	struct cpuidle_state *state_table;
98 
99 	/*
100 	 * Hardware C-state auto-demotion may not always be optimal.
101 	 * Indicate which enable bits to clear here.
102 	 */
103 	unsigned long auto_demotion_disable_flags;
104 	bool disable_promotion_to_c1e;
105 	bool c1_demotion_supported;
106 	bool use_acpi;
107 };
108 
109 static bool c1_demotion_supported;
110 static DEFINE_MUTEX(c1_demotion_mutex);
111 
112 static struct device *sysfs_root __initdata;
113 
114 static const struct idle_cpu *icpu __initdata;
115 static struct cpuidle_state *cpuidle_state_table __initdata;
116 
117 /* C-states data from the 'intel_idle.table' cmdline parameter */
118 static struct cpuidle_state cmdline_states[CPUIDLE_STATE_MAX] __initdata;
119 
120 static unsigned int mwait_substates __initdata;
121 
122 /*
123  * Enable interrupts before entering the C-state. On some platforms and for
124  * some C-states, this may measurably decrease interrupt latency.
125  */
126 #define CPUIDLE_FLAG_IRQ_ENABLE		BIT(14)
127 
128 /*
129  * Enable this state by default even if the ACPI _CST does not list it.
130  */
131 #define CPUIDLE_FLAG_ALWAYS_ENABLE	BIT(15)
132 
133 /*
134  * Disable IBRS across idle (when KERNEL_IBRS), is exclusive vs IRQ_ENABLE
135  * above.
136  */
137 #define CPUIDLE_FLAG_IBRS		BIT(16)
138 
139 /*
140  * Initialize large xstate for the C6-state entrance.
141  */
142 #define CPUIDLE_FLAG_INIT_XSTATE	BIT(17)
143 
144 /*
145  * Ignore the sub-state when matching mwait hints between the ACPI _CST and
146  * custom tables.
147  */
148 #define CPUIDLE_FLAG_PARTIAL_HINT_MATCH	BIT(18)
149 
150 /*
151  * MWAIT takes an 8-bit "hint" in EAX "suggesting"
152  * the C-state (top nibble) and sub-state (bottom nibble)
153  * 0x00 means "MWAIT(C1)", 0x10 means "MWAIT(C2)" etc.
154  *
155  * We store the hint at the top of our "flags" for each state.
156  */
157 #define flg2MWAIT(flags) (((flags) >> 24) & 0xFF)
158 #define MWAIT2flg(eax) ((eax & 0xFF) << 24)
159 
160 static __always_inline int __intel_idle(struct cpuidle_device *dev,
161 					struct cpuidle_driver *drv,
162 					int index, bool irqoff)
163 {
164 	struct cpuidle_state *state = &drv->states[index];
165 	unsigned int eax = flg2MWAIT(state->flags);
166 	unsigned int ecx = 1*irqoff; /* break on interrupt flag */
167 
168 	mwait_idle_with_hints(eax, ecx);
169 
170 	return index;
171 }
172 
173 /**
174  * intel_idle - Ask the processor to enter the given idle state.
175  * @dev: cpuidle device of the target CPU.
176  * @drv: cpuidle driver (assumed to point to intel_idle_driver).
177  * @index: Target idle state index.
178  *
179  * Use the MWAIT instruction to notify the processor that the CPU represented by
180  * @dev is idle and it can try to enter the idle state corresponding to @index.
181  *
182  * If the local APIC timer is not known to be reliable in the target idle state,
183  * enable one-shot tick broadcasting for the target CPU before executing MWAIT.
184  *
185  * Must be called under local_irq_disable().
186  */
187 static __cpuidle int intel_idle(struct cpuidle_device *dev,
188 				struct cpuidle_driver *drv, int index)
189 {
190 	return __intel_idle(dev, drv, index, true);
191 }
192 
193 static __cpuidle int intel_idle_irq(struct cpuidle_device *dev,
194 				    struct cpuidle_driver *drv, int index)
195 {
196 	return __intel_idle(dev, drv, index, false);
197 }
198 
199 static __cpuidle int intel_idle_ibrs(struct cpuidle_device *dev,
200 				     struct cpuidle_driver *drv, int index)
201 {
202 	bool smt_active = sched_smt_active();
203 	u64 spec_ctrl = spec_ctrl_current();
204 	int ret;
205 
206 	if (smt_active)
207 		__update_spec_ctrl(0);
208 
209 	ret = __intel_idle(dev, drv, index, true);
210 
211 	if (smt_active)
212 		__update_spec_ctrl(spec_ctrl);
213 
214 	return ret;
215 }
216 
217 static __cpuidle int intel_idle_xstate(struct cpuidle_device *dev,
218 				       struct cpuidle_driver *drv, int index)
219 {
220 	fpu_idle_fpregs();
221 	return __intel_idle(dev, drv, index, true);
222 }
223 
224 /**
225  * intel_idle_s2idle - Ask the processor to enter the given idle state.
226  * @dev: cpuidle device of the target CPU.
227  * @drv: cpuidle driver (assumed to point to intel_idle_driver).
228  * @index: Target idle state index.
229  *
230  * Use the MWAIT instruction to notify the processor that the CPU represented by
231  * @dev is idle and it can try to enter the idle state corresponding to @index.
232  *
233  * Invoked as a suspend-to-idle callback routine with frozen user space, frozen
234  * scheduler tick and suspended scheduler clock on the target CPU.
235  */
236 static __cpuidle int intel_idle_s2idle(struct cpuidle_device *dev,
237 				       struct cpuidle_driver *drv, int index)
238 {
239 	struct cpuidle_state *state = &drv->states[index];
240 	unsigned int eax = flg2MWAIT(state->flags);
241 	unsigned int ecx = 1; /* break on interrupt flag */
242 
243 	if (state->flags & CPUIDLE_FLAG_INIT_XSTATE)
244 		fpu_idle_fpregs();
245 
246 	mwait_idle_with_hints(eax, ecx);
247 
248 	return 0;
249 }
250 
251 static void intel_idle_enter_dead(struct cpuidle_device *dev, int index)
252 {
253 	struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
254 	struct cpuidle_state *state = &drv->states[index];
255 	unsigned long eax = flg2MWAIT(state->flags);
256 
257 	mwait_play_dead(eax);
258 }
259 
260 /*
261  * States are indexed by the cstate number,
262  * which is also the index into the MWAIT hint array.
263  * Thus C0 is a dummy.
264  */
265 static struct cpuidle_state nehalem_cstates[] __initdata = {
266 	{
267 		.name = "C1",
268 		.desc = "MWAIT 0x00",
269 		.flags = MWAIT2flg(0x00),
270 		.exit_latency = 3,
271 		.target_residency = 6,
272 		.enter = intel_idle,
273 		.enter_s2idle = intel_idle_s2idle, },
274 	{
275 		.name = "C1E",
276 		.desc = "MWAIT 0x01",
277 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
278 		.exit_latency = 10,
279 		.target_residency = 20,
280 		.enter = intel_idle,
281 		.enter_s2idle = intel_idle_s2idle, },
282 	{
283 		.name = "C3",
284 		.desc = "MWAIT 0x10",
285 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
286 		.exit_latency = 20,
287 		.target_residency = 80,
288 		.enter = intel_idle,
289 		.enter_s2idle = intel_idle_s2idle, },
290 	{
291 		.name = "C6",
292 		.desc = "MWAIT 0x20",
293 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
294 		.exit_latency = 200,
295 		.target_residency = 800,
296 		.enter = intel_idle,
297 		.enter_s2idle = intel_idle_s2idle, },
298 	{
299 		.enter = NULL }
300 };
301 
302 static struct cpuidle_state snb_cstates[] __initdata = {
303 	{
304 		.name = "C1",
305 		.desc = "MWAIT 0x00",
306 		.flags = MWAIT2flg(0x00),
307 		.exit_latency = 2,
308 		.target_residency = 2,
309 		.enter = intel_idle,
310 		.enter_s2idle = intel_idle_s2idle, },
311 	{
312 		.name = "C1E",
313 		.desc = "MWAIT 0x01",
314 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
315 		.exit_latency = 10,
316 		.target_residency = 20,
317 		.enter = intel_idle,
318 		.enter_s2idle = intel_idle_s2idle, },
319 	{
320 		.name = "C3",
321 		.desc = "MWAIT 0x10",
322 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
323 		.exit_latency = 80,
324 		.target_residency = 211,
325 		.enter = intel_idle,
326 		.enter_s2idle = intel_idle_s2idle, },
327 	{
328 		.name = "C6",
329 		.desc = "MWAIT 0x20",
330 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
331 		.exit_latency = 104,
332 		.target_residency = 345,
333 		.enter = intel_idle,
334 		.enter_s2idle = intel_idle_s2idle, },
335 	{
336 		.name = "C7",
337 		.desc = "MWAIT 0x30",
338 		.flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
339 		.exit_latency = 109,
340 		.target_residency = 345,
341 		.enter = intel_idle,
342 		.enter_s2idle = intel_idle_s2idle, },
343 	{
344 		.enter = NULL }
345 };
346 
347 static struct cpuidle_state byt_cstates[] __initdata = {
348 	{
349 		.name = "C1",
350 		.desc = "MWAIT 0x00",
351 		.flags = MWAIT2flg(0x00),
352 		.exit_latency = 1,
353 		.target_residency = 1,
354 		.enter = intel_idle,
355 		.enter_s2idle = intel_idle_s2idle, },
356 	{
357 		.name = "C6N",
358 		.desc = "MWAIT 0x58",
359 		.flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
360 		.exit_latency = 300,
361 		.target_residency = 275,
362 		.enter = intel_idle,
363 		.enter_s2idle = intel_idle_s2idle, },
364 	{
365 		.name = "C6S",
366 		.desc = "MWAIT 0x52",
367 		.flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
368 		.exit_latency = 500,
369 		.target_residency = 560,
370 		.enter = intel_idle,
371 		.enter_s2idle = intel_idle_s2idle, },
372 	{
373 		.name = "C7",
374 		.desc = "MWAIT 0x60",
375 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
376 		.exit_latency = 1200,
377 		.target_residency = 4000,
378 		.enter = intel_idle,
379 		.enter_s2idle = intel_idle_s2idle, },
380 	{
381 		.name = "C7S",
382 		.desc = "MWAIT 0x64",
383 		.flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
384 		.exit_latency = 10000,
385 		.target_residency = 20000,
386 		.enter = intel_idle,
387 		.enter_s2idle = intel_idle_s2idle, },
388 	{
389 		.enter = NULL }
390 };
391 
392 static struct cpuidle_state cht_cstates[] __initdata = {
393 	{
394 		.name = "C1",
395 		.desc = "MWAIT 0x00",
396 		.flags = MWAIT2flg(0x00),
397 		.exit_latency = 1,
398 		.target_residency = 1,
399 		.enter = intel_idle,
400 		.enter_s2idle = intel_idle_s2idle, },
401 	{
402 		.name = "C6N",
403 		.desc = "MWAIT 0x58",
404 		.flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
405 		.exit_latency = 80,
406 		.target_residency = 275,
407 		.enter = intel_idle,
408 		.enter_s2idle = intel_idle_s2idle, },
409 	{
410 		.name = "C6S",
411 		.desc = "MWAIT 0x52",
412 		.flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
413 		.exit_latency = 200,
414 		.target_residency = 560,
415 		.enter = intel_idle,
416 		.enter_s2idle = intel_idle_s2idle, },
417 	{
418 		.name = "C7",
419 		.desc = "MWAIT 0x60",
420 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
421 		.exit_latency = 1200,
422 		.target_residency = 4000,
423 		.enter = intel_idle,
424 		.enter_s2idle = intel_idle_s2idle, },
425 	{
426 		.name = "C7S",
427 		.desc = "MWAIT 0x64",
428 		.flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
429 		.exit_latency = 10000,
430 		.target_residency = 20000,
431 		.enter = intel_idle,
432 		.enter_s2idle = intel_idle_s2idle, },
433 	{
434 		.enter = NULL }
435 };
436 
437 static struct cpuidle_state ivb_cstates[] __initdata = {
438 	{
439 		.name = "C1",
440 		.desc = "MWAIT 0x00",
441 		.flags = MWAIT2flg(0x00),
442 		.exit_latency = 1,
443 		.target_residency = 1,
444 		.enter = intel_idle,
445 		.enter_s2idle = intel_idle_s2idle, },
446 	{
447 		.name = "C1E",
448 		.desc = "MWAIT 0x01",
449 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
450 		.exit_latency = 10,
451 		.target_residency = 20,
452 		.enter = intel_idle,
453 		.enter_s2idle = intel_idle_s2idle, },
454 	{
455 		.name = "C3",
456 		.desc = "MWAIT 0x10",
457 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
458 		.exit_latency = 59,
459 		.target_residency = 156,
460 		.enter = intel_idle,
461 		.enter_s2idle = intel_idle_s2idle, },
462 	{
463 		.name = "C6",
464 		.desc = "MWAIT 0x20",
465 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
466 		.exit_latency = 80,
467 		.target_residency = 300,
468 		.enter = intel_idle,
469 		.enter_s2idle = intel_idle_s2idle, },
470 	{
471 		.name = "C7",
472 		.desc = "MWAIT 0x30",
473 		.flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
474 		.exit_latency = 87,
475 		.target_residency = 300,
476 		.enter = intel_idle,
477 		.enter_s2idle = intel_idle_s2idle, },
478 	{
479 		.enter = NULL }
480 };
481 
482 static struct cpuidle_state ivt_cstates[] __initdata = {
483 	{
484 		.name = "C1",
485 		.desc = "MWAIT 0x00",
486 		.flags = MWAIT2flg(0x00),
487 		.exit_latency = 1,
488 		.target_residency = 1,
489 		.enter = intel_idle,
490 		.enter_s2idle = intel_idle_s2idle, },
491 	{
492 		.name = "C1E",
493 		.desc = "MWAIT 0x01",
494 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
495 		.exit_latency = 10,
496 		.target_residency = 80,
497 		.enter = intel_idle,
498 		.enter_s2idle = intel_idle_s2idle, },
499 	{
500 		.name = "C3",
501 		.desc = "MWAIT 0x10",
502 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
503 		.exit_latency = 59,
504 		.target_residency = 156,
505 		.enter = intel_idle,
506 		.enter_s2idle = intel_idle_s2idle, },
507 	{
508 		.name = "C6",
509 		.desc = "MWAIT 0x20",
510 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
511 		.exit_latency = 82,
512 		.target_residency = 300,
513 		.enter = intel_idle,
514 		.enter_s2idle = intel_idle_s2idle, },
515 	{
516 		.enter = NULL }
517 };
518 
519 static struct cpuidle_state ivt_cstates_4s[] __initdata = {
520 	{
521 		.name = "C1",
522 		.desc = "MWAIT 0x00",
523 		.flags = MWAIT2flg(0x00),
524 		.exit_latency = 1,
525 		.target_residency = 1,
526 		.enter = intel_idle,
527 		.enter_s2idle = intel_idle_s2idle, },
528 	{
529 		.name = "C1E",
530 		.desc = "MWAIT 0x01",
531 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
532 		.exit_latency = 10,
533 		.target_residency = 250,
534 		.enter = intel_idle,
535 		.enter_s2idle = intel_idle_s2idle, },
536 	{
537 		.name = "C3",
538 		.desc = "MWAIT 0x10",
539 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
540 		.exit_latency = 59,
541 		.target_residency = 300,
542 		.enter = intel_idle,
543 		.enter_s2idle = intel_idle_s2idle, },
544 	{
545 		.name = "C6",
546 		.desc = "MWAIT 0x20",
547 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
548 		.exit_latency = 84,
549 		.target_residency = 400,
550 		.enter = intel_idle,
551 		.enter_s2idle = intel_idle_s2idle, },
552 	{
553 		.enter = NULL }
554 };
555 
556 static struct cpuidle_state ivt_cstates_8s[] __initdata = {
557 	{
558 		.name = "C1",
559 		.desc = "MWAIT 0x00",
560 		.flags = MWAIT2flg(0x00),
561 		.exit_latency = 1,
562 		.target_residency = 1,
563 		.enter = intel_idle,
564 		.enter_s2idle = intel_idle_s2idle, },
565 	{
566 		.name = "C1E",
567 		.desc = "MWAIT 0x01",
568 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
569 		.exit_latency = 10,
570 		.target_residency = 500,
571 		.enter = intel_idle,
572 		.enter_s2idle = intel_idle_s2idle, },
573 	{
574 		.name = "C3",
575 		.desc = "MWAIT 0x10",
576 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
577 		.exit_latency = 59,
578 		.target_residency = 600,
579 		.enter = intel_idle,
580 		.enter_s2idle = intel_idle_s2idle, },
581 	{
582 		.name = "C6",
583 		.desc = "MWAIT 0x20",
584 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
585 		.exit_latency = 88,
586 		.target_residency = 700,
587 		.enter = intel_idle,
588 		.enter_s2idle = intel_idle_s2idle, },
589 	{
590 		.enter = NULL }
591 };
592 
593 static struct cpuidle_state hsw_cstates[] __initdata = {
594 	{
595 		.name = "C1",
596 		.desc = "MWAIT 0x00",
597 		.flags = MWAIT2flg(0x00),
598 		.exit_latency = 2,
599 		.target_residency = 2,
600 		.enter = intel_idle,
601 		.enter_s2idle = intel_idle_s2idle, },
602 	{
603 		.name = "C1E",
604 		.desc = "MWAIT 0x01",
605 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
606 		.exit_latency = 10,
607 		.target_residency = 20,
608 		.enter = intel_idle,
609 		.enter_s2idle = intel_idle_s2idle, },
610 	{
611 		.name = "C3",
612 		.desc = "MWAIT 0x10",
613 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
614 		.exit_latency = 33,
615 		.target_residency = 100,
616 		.enter = intel_idle,
617 		.enter_s2idle = intel_idle_s2idle, },
618 	{
619 		.name = "C6",
620 		.desc = "MWAIT 0x20",
621 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
622 		.exit_latency = 133,
623 		.target_residency = 400,
624 		.enter = intel_idle,
625 		.enter_s2idle = intel_idle_s2idle, },
626 	{
627 		.name = "C7s",
628 		.desc = "MWAIT 0x32",
629 		.flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
630 		.exit_latency = 166,
631 		.target_residency = 500,
632 		.enter = intel_idle,
633 		.enter_s2idle = intel_idle_s2idle, },
634 	{
635 		.name = "C8",
636 		.desc = "MWAIT 0x40",
637 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
638 		.exit_latency = 300,
639 		.target_residency = 900,
640 		.enter = intel_idle,
641 		.enter_s2idle = intel_idle_s2idle, },
642 	{
643 		.name = "C9",
644 		.desc = "MWAIT 0x50",
645 		.flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
646 		.exit_latency = 600,
647 		.target_residency = 1800,
648 		.enter = intel_idle,
649 		.enter_s2idle = intel_idle_s2idle, },
650 	{
651 		.name = "C10",
652 		.desc = "MWAIT 0x60",
653 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
654 		.exit_latency = 2600,
655 		.target_residency = 7700,
656 		.enter = intel_idle,
657 		.enter_s2idle = intel_idle_s2idle, },
658 	{
659 		.enter = NULL }
660 };
661 static struct cpuidle_state bdw_cstates[] __initdata = {
662 	{
663 		.name = "C1",
664 		.desc = "MWAIT 0x00",
665 		.flags = MWAIT2flg(0x00),
666 		.exit_latency = 2,
667 		.target_residency = 2,
668 		.enter = intel_idle,
669 		.enter_s2idle = intel_idle_s2idle, },
670 	{
671 		.name = "C1E",
672 		.desc = "MWAIT 0x01",
673 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
674 		.exit_latency = 10,
675 		.target_residency = 20,
676 		.enter = intel_idle,
677 		.enter_s2idle = intel_idle_s2idle, },
678 	{
679 		.name = "C3",
680 		.desc = "MWAIT 0x10",
681 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
682 		.exit_latency = 40,
683 		.target_residency = 100,
684 		.enter = intel_idle,
685 		.enter_s2idle = intel_idle_s2idle, },
686 	{
687 		.name = "C6",
688 		.desc = "MWAIT 0x20",
689 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
690 		.exit_latency = 133,
691 		.target_residency = 400,
692 		.enter = intel_idle,
693 		.enter_s2idle = intel_idle_s2idle, },
694 	{
695 		.name = "C7s",
696 		.desc = "MWAIT 0x32",
697 		.flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
698 		.exit_latency = 166,
699 		.target_residency = 500,
700 		.enter = intel_idle,
701 		.enter_s2idle = intel_idle_s2idle, },
702 	{
703 		.name = "C8",
704 		.desc = "MWAIT 0x40",
705 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
706 		.exit_latency = 300,
707 		.target_residency = 900,
708 		.enter = intel_idle,
709 		.enter_s2idle = intel_idle_s2idle, },
710 	{
711 		.name = "C9",
712 		.desc = "MWAIT 0x50",
713 		.flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
714 		.exit_latency = 600,
715 		.target_residency = 1800,
716 		.enter = intel_idle,
717 		.enter_s2idle = intel_idle_s2idle, },
718 	{
719 		.name = "C10",
720 		.desc = "MWAIT 0x60",
721 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
722 		.exit_latency = 2600,
723 		.target_residency = 7700,
724 		.enter = intel_idle,
725 		.enter_s2idle = intel_idle_s2idle, },
726 	{
727 		.enter = NULL }
728 };
729 
730 static struct cpuidle_state skl_cstates[] __initdata = {
731 	{
732 		.name = "C1",
733 		.desc = "MWAIT 0x00",
734 		.flags = MWAIT2flg(0x00),
735 		.exit_latency = 2,
736 		.target_residency = 2,
737 		.enter = intel_idle,
738 		.enter_s2idle = intel_idle_s2idle, },
739 	{
740 		.name = "C1E",
741 		.desc = "MWAIT 0x01",
742 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
743 		.exit_latency = 10,
744 		.target_residency = 20,
745 		.enter = intel_idle,
746 		.enter_s2idle = intel_idle_s2idle, },
747 	{
748 		.name = "C3",
749 		.desc = "MWAIT 0x10",
750 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
751 		.exit_latency = 70,
752 		.target_residency = 100,
753 		.enter = intel_idle,
754 		.enter_s2idle = intel_idle_s2idle, },
755 	{
756 		.name = "C6",
757 		.desc = "MWAIT 0x20",
758 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
759 		.exit_latency = 85,
760 		.target_residency = 200,
761 		.enter = intel_idle,
762 		.enter_s2idle = intel_idle_s2idle, },
763 	{
764 		.name = "C7s",
765 		.desc = "MWAIT 0x33",
766 		.flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
767 		.exit_latency = 124,
768 		.target_residency = 800,
769 		.enter = intel_idle,
770 		.enter_s2idle = intel_idle_s2idle, },
771 	{
772 		.name = "C8",
773 		.desc = "MWAIT 0x40",
774 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
775 		.exit_latency = 200,
776 		.target_residency = 800,
777 		.enter = intel_idle,
778 		.enter_s2idle = intel_idle_s2idle, },
779 	{
780 		.name = "C9",
781 		.desc = "MWAIT 0x50",
782 		.flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
783 		.exit_latency = 480,
784 		.target_residency = 5000,
785 		.enter = intel_idle,
786 		.enter_s2idle = intel_idle_s2idle, },
787 	{
788 		.name = "C10",
789 		.desc = "MWAIT 0x60",
790 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
791 		.exit_latency = 890,
792 		.target_residency = 5000,
793 		.enter = intel_idle,
794 		.enter_s2idle = intel_idle_s2idle, },
795 	{
796 		.enter = NULL }
797 };
798 
799 static struct cpuidle_state skx_cstates[] __initdata = {
800 	{
801 		.name = "C1",
802 		.desc = "MWAIT 0x00",
803 		.flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_IRQ_ENABLE,
804 		.exit_latency = 2,
805 		.target_residency = 2,
806 		.enter = intel_idle,
807 		.enter_s2idle = intel_idle_s2idle, },
808 	{
809 		.name = "C1E",
810 		.desc = "MWAIT 0x01",
811 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
812 		.exit_latency = 10,
813 		.target_residency = 20,
814 		.enter = intel_idle,
815 		.enter_s2idle = intel_idle_s2idle, },
816 	{
817 		.name = "C6",
818 		.desc = "MWAIT 0x20",
819 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED | CPUIDLE_FLAG_IBRS,
820 		.exit_latency = 133,
821 		.target_residency = 600,
822 		.enter = intel_idle,
823 		.enter_s2idle = intel_idle_s2idle, },
824 	{
825 		.enter = NULL }
826 };
827 
828 static struct cpuidle_state icx_cstates[] __initdata = {
829 	{
830 		.name = "C1",
831 		.desc = "MWAIT 0x00",
832 		.flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_IRQ_ENABLE,
833 		.exit_latency = 1,
834 		.target_residency = 1,
835 		.enter = intel_idle,
836 		.enter_s2idle = intel_idle_s2idle, },
837 	{
838 		.name = "C1E",
839 		.desc = "MWAIT 0x01",
840 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
841 		.exit_latency = 4,
842 		.target_residency = 4,
843 		.enter = intel_idle,
844 		.enter_s2idle = intel_idle_s2idle, },
845 	{
846 		.name = "C6",
847 		.desc = "MWAIT 0x20",
848 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
849 		.exit_latency = 170,
850 		.target_residency = 600,
851 		.enter = intel_idle,
852 		.enter_s2idle = intel_idle_s2idle, },
853 	{
854 		.enter = NULL }
855 };
856 
857 /*
858  * On AlderLake C1 has to be disabled if C1E is enabled, and vice versa.
859  * C1E is enabled only if "C1E promotion" bit is set in MSR_IA32_POWER_CTL.
860  * But in this case there is effectively no C1, because C1 requests are
861  * promoted to C1E. If the "C1E promotion" bit is cleared, then both C1
862  * and C1E requests end up with C1, so there is effectively no C1E.
863  *
864  * By default we enable C1E and disable C1 by marking it with
865  * 'CPUIDLE_FLAG_UNUSABLE'.
866  */
867 static struct cpuidle_state adl_cstates[] __initdata = {
868 	{
869 		.name = "C1",
870 		.desc = "MWAIT 0x00",
871 		.flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_UNUSABLE,
872 		.exit_latency = 1,
873 		.target_residency = 1,
874 		.enter = intel_idle,
875 		.enter_s2idle = intel_idle_s2idle, },
876 	{
877 		.name = "C1E",
878 		.desc = "MWAIT 0x01",
879 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
880 		.exit_latency = 2,
881 		.target_residency = 4,
882 		.enter = intel_idle,
883 		.enter_s2idle = intel_idle_s2idle, },
884 	{
885 		.name = "C6",
886 		.desc = "MWAIT 0x20",
887 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
888 		.exit_latency = 220,
889 		.target_residency = 600,
890 		.enter = intel_idle,
891 		.enter_s2idle = intel_idle_s2idle, },
892 	{
893 		.name = "C8",
894 		.desc = "MWAIT 0x40",
895 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
896 		.exit_latency = 280,
897 		.target_residency = 800,
898 		.enter = intel_idle,
899 		.enter_s2idle = intel_idle_s2idle, },
900 	{
901 		.name = "C10",
902 		.desc = "MWAIT 0x60",
903 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
904 		.exit_latency = 680,
905 		.target_residency = 2000,
906 		.enter = intel_idle,
907 		.enter_s2idle = intel_idle_s2idle, },
908 	{
909 		.enter = NULL }
910 };
911 
912 static struct cpuidle_state adl_l_cstates[] __initdata = {
913 	{
914 		.name = "C1",
915 		.desc = "MWAIT 0x00",
916 		.flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_UNUSABLE,
917 		.exit_latency = 1,
918 		.target_residency = 1,
919 		.enter = intel_idle,
920 		.enter_s2idle = intel_idle_s2idle, },
921 	{
922 		.name = "C1E",
923 		.desc = "MWAIT 0x01",
924 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
925 		.exit_latency = 2,
926 		.target_residency = 4,
927 		.enter = intel_idle,
928 		.enter_s2idle = intel_idle_s2idle, },
929 	{
930 		.name = "C6",
931 		.desc = "MWAIT 0x20",
932 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
933 		.exit_latency = 170,
934 		.target_residency = 500,
935 		.enter = intel_idle,
936 		.enter_s2idle = intel_idle_s2idle, },
937 	{
938 		.name = "C8",
939 		.desc = "MWAIT 0x40",
940 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
941 		.exit_latency = 200,
942 		.target_residency = 600,
943 		.enter = intel_idle,
944 		.enter_s2idle = intel_idle_s2idle, },
945 	{
946 		.name = "C10",
947 		.desc = "MWAIT 0x60",
948 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
949 		.exit_latency = 230,
950 		.target_residency = 700,
951 		.enter = intel_idle,
952 		.enter_s2idle = intel_idle_s2idle, },
953 	{
954 		.enter = NULL }
955 };
956 
957 static struct cpuidle_state mtl_l_cstates[] __initdata = {
958 	{
959 		.name = "C1E",
960 		.desc = "MWAIT 0x01",
961 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
962 		.exit_latency = 1,
963 		.target_residency = 1,
964 		.enter = intel_idle,
965 		.enter_s2idle = intel_idle_s2idle, },
966 	{
967 		.name = "C6",
968 		.desc = "MWAIT 0x20",
969 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
970 		.exit_latency = 140,
971 		.target_residency = 420,
972 		.enter = intel_idle,
973 		.enter_s2idle = intel_idle_s2idle, },
974 	{
975 		.name = "C10",
976 		.desc = "MWAIT 0x60",
977 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
978 		.exit_latency = 310,
979 		.target_residency = 930,
980 		.enter = intel_idle,
981 		.enter_s2idle = intel_idle_s2idle, },
982 	{
983 		.enter = NULL }
984 };
985 
986 static struct cpuidle_state gmt_cstates[] __initdata = {
987 	{
988 		.name = "C1",
989 		.desc = "MWAIT 0x00",
990 		.flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_UNUSABLE,
991 		.exit_latency = 1,
992 		.target_residency = 1,
993 		.enter = intel_idle,
994 		.enter_s2idle = intel_idle_s2idle, },
995 	{
996 		.name = "C1E",
997 		.desc = "MWAIT 0x01",
998 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
999 		.exit_latency = 2,
1000 		.target_residency = 4,
1001 		.enter = intel_idle,
1002 		.enter_s2idle = intel_idle_s2idle, },
1003 	{
1004 		.name = "C6",
1005 		.desc = "MWAIT 0x20",
1006 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
1007 		.exit_latency = 195,
1008 		.target_residency = 585,
1009 		.enter = intel_idle,
1010 		.enter_s2idle = intel_idle_s2idle, },
1011 	{
1012 		.name = "C8",
1013 		.desc = "MWAIT 0x40",
1014 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
1015 		.exit_latency = 260,
1016 		.target_residency = 1040,
1017 		.enter = intel_idle,
1018 		.enter_s2idle = intel_idle_s2idle, },
1019 	{
1020 		.name = "C10",
1021 		.desc = "MWAIT 0x60",
1022 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
1023 		.exit_latency = 660,
1024 		.target_residency = 1980,
1025 		.enter = intel_idle,
1026 		.enter_s2idle = intel_idle_s2idle, },
1027 	{
1028 		.enter = NULL }
1029 };
1030 
1031 static struct cpuidle_state spr_cstates[] __initdata = {
1032 	{
1033 		.name = "C1",
1034 		.desc = "MWAIT 0x00",
1035 		.flags = MWAIT2flg(0x00),
1036 		.exit_latency = 1,
1037 		.target_residency = 1,
1038 		.enter = intel_idle,
1039 		.enter_s2idle = intel_idle_s2idle, },
1040 	{
1041 		.name = "C1E",
1042 		.desc = "MWAIT 0x01",
1043 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1044 		.exit_latency = 2,
1045 		.target_residency = 4,
1046 		.enter = intel_idle,
1047 		.enter_s2idle = intel_idle_s2idle, },
1048 	{
1049 		.name = "C6",
1050 		.desc = "MWAIT 0x20",
1051 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED |
1052 					   CPUIDLE_FLAG_INIT_XSTATE,
1053 		.exit_latency = 290,
1054 		.target_residency = 800,
1055 		.enter = intel_idle,
1056 		.enter_s2idle = intel_idle_s2idle, },
1057 	{
1058 		.enter = NULL }
1059 };
1060 
1061 static struct cpuidle_state gnr_cstates[] __initdata = {
1062 	{
1063 		.name = "C1",
1064 		.desc = "MWAIT 0x00",
1065 		.flags = MWAIT2flg(0x00),
1066 		.exit_latency = 1,
1067 		.target_residency = 1,
1068 		.enter = intel_idle,
1069 		.enter_s2idle = intel_idle_s2idle, },
1070 	{
1071 		.name = "C1E",
1072 		.desc = "MWAIT 0x01",
1073 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1074 		.exit_latency = 4,
1075 		.target_residency = 4,
1076 		.enter = intel_idle,
1077 		.enter_s2idle = intel_idle_s2idle, },
1078 	{
1079 		.name = "C6",
1080 		.desc = "MWAIT 0x20",
1081 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED |
1082 					   CPUIDLE_FLAG_INIT_XSTATE |
1083 					   CPUIDLE_FLAG_PARTIAL_HINT_MATCH,
1084 		.exit_latency = 170,
1085 		.target_residency = 650,
1086 		.enter = intel_idle,
1087 		.enter_s2idle = intel_idle_s2idle, },
1088 	{
1089 		.name = "C6P",
1090 		.desc = "MWAIT 0x21",
1091 		.flags = MWAIT2flg(0x21) | CPUIDLE_FLAG_TLB_FLUSHED |
1092 					   CPUIDLE_FLAG_INIT_XSTATE |
1093 					   CPUIDLE_FLAG_PARTIAL_HINT_MATCH,
1094 		.exit_latency = 210,
1095 		.target_residency = 1000,
1096 		.enter = intel_idle,
1097 		.enter_s2idle = intel_idle_s2idle, },
1098 	{
1099 		.enter = NULL }
1100 };
1101 
1102 static struct cpuidle_state gnrd_cstates[] __initdata = {
1103 	{
1104 		.name = "C1",
1105 		.desc = "MWAIT 0x00",
1106 		.flags = MWAIT2flg(0x00),
1107 		.exit_latency = 1,
1108 		.target_residency = 1,
1109 		.enter = intel_idle,
1110 		.enter_s2idle = intel_idle_s2idle, },
1111 	{
1112 		.name = "C1E",
1113 		.desc = "MWAIT 0x01",
1114 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1115 		.exit_latency = 4,
1116 		.target_residency = 4,
1117 		.enter = intel_idle,
1118 		.enter_s2idle = intel_idle_s2idle, },
1119 	{
1120 		.name = "C6",
1121 		.desc = "MWAIT 0x20",
1122 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED |
1123 					   CPUIDLE_FLAG_INIT_XSTATE |
1124 					   CPUIDLE_FLAG_PARTIAL_HINT_MATCH,
1125 		.exit_latency = 220,
1126 		.target_residency = 650,
1127 		.enter = intel_idle,
1128 		.enter_s2idle = intel_idle_s2idle, },
1129 	{
1130 		.name = "C6P",
1131 		.desc = "MWAIT 0x21",
1132 		.flags = MWAIT2flg(0x21) | CPUIDLE_FLAG_TLB_FLUSHED |
1133 					   CPUIDLE_FLAG_INIT_XSTATE |
1134 					   CPUIDLE_FLAG_PARTIAL_HINT_MATCH,
1135 		.exit_latency = 240,
1136 		.target_residency = 750,
1137 		.enter = intel_idle,
1138 		.enter_s2idle = intel_idle_s2idle, },
1139 	{
1140 		.enter = NULL }
1141 };
1142 
1143 static struct cpuidle_state atom_cstates[] __initdata = {
1144 	{
1145 		.name = "C1E",
1146 		.desc = "MWAIT 0x00",
1147 		.flags = MWAIT2flg(0x00),
1148 		.exit_latency = 10,
1149 		.target_residency = 20,
1150 		.enter = intel_idle,
1151 		.enter_s2idle = intel_idle_s2idle, },
1152 	{
1153 		.name = "C2",
1154 		.desc = "MWAIT 0x10",
1155 		.flags = MWAIT2flg(0x10),
1156 		.exit_latency = 20,
1157 		.target_residency = 80,
1158 		.enter = intel_idle,
1159 		.enter_s2idle = intel_idle_s2idle, },
1160 	{
1161 		.name = "C4",
1162 		.desc = "MWAIT 0x30",
1163 		.flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
1164 		.exit_latency = 100,
1165 		.target_residency = 400,
1166 		.enter = intel_idle,
1167 		.enter_s2idle = intel_idle_s2idle, },
1168 	{
1169 		.name = "C6",
1170 		.desc = "MWAIT 0x52",
1171 		.flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
1172 		.exit_latency = 140,
1173 		.target_residency = 560,
1174 		.enter = intel_idle,
1175 		.enter_s2idle = intel_idle_s2idle, },
1176 	{
1177 		.enter = NULL }
1178 };
1179 static struct cpuidle_state tangier_cstates[] __initdata = {
1180 	{
1181 		.name = "C1",
1182 		.desc = "MWAIT 0x00",
1183 		.flags = MWAIT2flg(0x00),
1184 		.exit_latency = 1,
1185 		.target_residency = 4,
1186 		.enter = intel_idle,
1187 		.enter_s2idle = intel_idle_s2idle, },
1188 	{
1189 		.name = "C4",
1190 		.desc = "MWAIT 0x30",
1191 		.flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
1192 		.exit_latency = 100,
1193 		.target_residency = 400,
1194 		.enter = intel_idle,
1195 		.enter_s2idle = intel_idle_s2idle, },
1196 	{
1197 		.name = "C6",
1198 		.desc = "MWAIT 0x52",
1199 		.flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
1200 		.exit_latency = 140,
1201 		.target_residency = 560,
1202 		.enter = intel_idle,
1203 		.enter_s2idle = intel_idle_s2idle, },
1204 	{
1205 		.name = "C7",
1206 		.desc = "MWAIT 0x60",
1207 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
1208 		.exit_latency = 1200,
1209 		.target_residency = 4000,
1210 		.enter = intel_idle,
1211 		.enter_s2idle = intel_idle_s2idle, },
1212 	{
1213 		.name = "C9",
1214 		.desc = "MWAIT 0x64",
1215 		.flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
1216 		.exit_latency = 10000,
1217 		.target_residency = 20000,
1218 		.enter = intel_idle,
1219 		.enter_s2idle = intel_idle_s2idle, },
1220 	{
1221 		.enter = NULL }
1222 };
1223 static struct cpuidle_state avn_cstates[] __initdata = {
1224 	{
1225 		.name = "C1",
1226 		.desc = "MWAIT 0x00",
1227 		.flags = MWAIT2flg(0x00),
1228 		.exit_latency = 2,
1229 		.target_residency = 2,
1230 		.enter = intel_idle,
1231 		.enter_s2idle = intel_idle_s2idle, },
1232 	{
1233 		.name = "C6",
1234 		.desc = "MWAIT 0x51",
1235 		.flags = MWAIT2flg(0x51) | CPUIDLE_FLAG_TLB_FLUSHED,
1236 		.exit_latency = 15,
1237 		.target_residency = 45,
1238 		.enter = intel_idle,
1239 		.enter_s2idle = intel_idle_s2idle, },
1240 	{
1241 		.enter = NULL }
1242 };
1243 static struct cpuidle_state knl_cstates[] __initdata = {
1244 	{
1245 		.name = "C1",
1246 		.desc = "MWAIT 0x00",
1247 		.flags = MWAIT2flg(0x00),
1248 		.exit_latency = 1,
1249 		.target_residency = 2,
1250 		.enter = intel_idle,
1251 		.enter_s2idle = intel_idle_s2idle },
1252 	{
1253 		.name = "C6",
1254 		.desc = "MWAIT 0x10",
1255 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
1256 		.exit_latency = 120,
1257 		.target_residency = 500,
1258 		.enter = intel_idle,
1259 		.enter_s2idle = intel_idle_s2idle },
1260 	{
1261 		.enter = NULL }
1262 };
1263 
1264 static struct cpuidle_state bxt_cstates[] __initdata = {
1265 	{
1266 		.name = "C1",
1267 		.desc = "MWAIT 0x00",
1268 		.flags = MWAIT2flg(0x00),
1269 		.exit_latency = 2,
1270 		.target_residency = 2,
1271 		.enter = intel_idle,
1272 		.enter_s2idle = intel_idle_s2idle, },
1273 	{
1274 		.name = "C1E",
1275 		.desc = "MWAIT 0x01",
1276 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1277 		.exit_latency = 10,
1278 		.target_residency = 20,
1279 		.enter = intel_idle,
1280 		.enter_s2idle = intel_idle_s2idle, },
1281 	{
1282 		.name = "C6",
1283 		.desc = "MWAIT 0x20",
1284 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
1285 		.exit_latency = 133,
1286 		.target_residency = 133,
1287 		.enter = intel_idle,
1288 		.enter_s2idle = intel_idle_s2idle, },
1289 	{
1290 		.name = "C7s",
1291 		.desc = "MWAIT 0x31",
1292 		.flags = MWAIT2flg(0x31) | CPUIDLE_FLAG_TLB_FLUSHED,
1293 		.exit_latency = 155,
1294 		.target_residency = 155,
1295 		.enter = intel_idle,
1296 		.enter_s2idle = intel_idle_s2idle, },
1297 	{
1298 		.name = "C8",
1299 		.desc = "MWAIT 0x40",
1300 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
1301 		.exit_latency = 1000,
1302 		.target_residency = 1000,
1303 		.enter = intel_idle,
1304 		.enter_s2idle = intel_idle_s2idle, },
1305 	{
1306 		.name = "C9",
1307 		.desc = "MWAIT 0x50",
1308 		.flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
1309 		.exit_latency = 2000,
1310 		.target_residency = 2000,
1311 		.enter = intel_idle,
1312 		.enter_s2idle = intel_idle_s2idle, },
1313 	{
1314 		.name = "C10",
1315 		.desc = "MWAIT 0x60",
1316 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
1317 		.exit_latency = 10000,
1318 		.target_residency = 10000,
1319 		.enter = intel_idle,
1320 		.enter_s2idle = intel_idle_s2idle, },
1321 	{
1322 		.enter = NULL }
1323 };
1324 
1325 static struct cpuidle_state dnv_cstates[] __initdata = {
1326 	{
1327 		.name = "C1",
1328 		.desc = "MWAIT 0x00",
1329 		.flags = MWAIT2flg(0x00),
1330 		.exit_latency = 2,
1331 		.target_residency = 2,
1332 		.enter = intel_idle,
1333 		.enter_s2idle = intel_idle_s2idle, },
1334 	{
1335 		.name = "C1E",
1336 		.desc = "MWAIT 0x01",
1337 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1338 		.exit_latency = 10,
1339 		.target_residency = 20,
1340 		.enter = intel_idle,
1341 		.enter_s2idle = intel_idle_s2idle, },
1342 	{
1343 		.name = "C6",
1344 		.desc = "MWAIT 0x20",
1345 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
1346 		.exit_latency = 50,
1347 		.target_residency = 500,
1348 		.enter = intel_idle,
1349 		.enter_s2idle = intel_idle_s2idle, },
1350 	{
1351 		.enter = NULL }
1352 };
1353 
1354 /*
1355  * Note, depending on HW and FW revision, SnowRidge SoC may or may not support
1356  * C6, and this is indicated in the CPUID mwait leaf.
1357  */
1358 static struct cpuidle_state snr_cstates[] __initdata = {
1359 	{
1360 		.name = "C1",
1361 		.desc = "MWAIT 0x00",
1362 		.flags = MWAIT2flg(0x00),
1363 		.exit_latency = 2,
1364 		.target_residency = 2,
1365 		.enter = intel_idle,
1366 		.enter_s2idle = intel_idle_s2idle, },
1367 	{
1368 		.name = "C1E",
1369 		.desc = "MWAIT 0x01",
1370 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1371 		.exit_latency = 15,
1372 		.target_residency = 25,
1373 		.enter = intel_idle,
1374 		.enter_s2idle = intel_idle_s2idle, },
1375 	{
1376 		.name = "C6",
1377 		.desc = "MWAIT 0x20",
1378 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
1379 		.exit_latency = 130,
1380 		.target_residency = 500,
1381 		.enter = intel_idle,
1382 		.enter_s2idle = intel_idle_s2idle, },
1383 	{
1384 		.enter = NULL }
1385 };
1386 
1387 static struct cpuidle_state grr_cstates[] __initdata = {
1388 	{
1389 		.name = "C1",
1390 		.desc = "MWAIT 0x00",
1391 		.flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1392 		.exit_latency = 1,
1393 		.target_residency = 1,
1394 		.enter = intel_idle,
1395 		.enter_s2idle = intel_idle_s2idle, },
1396 	{
1397 		.name = "C1E",
1398 		.desc = "MWAIT 0x01",
1399 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1400 		.exit_latency = 2,
1401 		.target_residency = 10,
1402 		.enter = intel_idle,
1403 		.enter_s2idle = intel_idle_s2idle, },
1404 	{
1405 		.name = "C6S",
1406 		.desc = "MWAIT 0x22",
1407 		.flags = MWAIT2flg(0x22) | CPUIDLE_FLAG_TLB_FLUSHED,
1408 		.exit_latency = 140,
1409 		.target_residency = 500,
1410 		.enter = intel_idle,
1411 		.enter_s2idle = intel_idle_s2idle, },
1412 	{
1413 		.enter = NULL }
1414 };
1415 
1416 static struct cpuidle_state srf_cstates[] __initdata = {
1417 	{
1418 		.name = "C1",
1419 		.desc = "MWAIT 0x00",
1420 		.flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1421 		.exit_latency = 1,
1422 		.target_residency = 1,
1423 		.enter = intel_idle,
1424 		.enter_s2idle = intel_idle_s2idle, },
1425 	{
1426 		.name = "C1E",
1427 		.desc = "MWAIT 0x01",
1428 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
1429 		.exit_latency = 2,
1430 		.target_residency = 10,
1431 		.enter = intel_idle,
1432 		.enter_s2idle = intel_idle_s2idle, },
1433 	{
1434 		.name = "C6S",
1435 		.desc = "MWAIT 0x22",
1436 		.flags = MWAIT2flg(0x22) | CPUIDLE_FLAG_TLB_FLUSHED |
1437 					   CPUIDLE_FLAG_PARTIAL_HINT_MATCH,
1438 		.exit_latency = 270,
1439 		.target_residency = 700,
1440 		.enter = intel_idle,
1441 		.enter_s2idle = intel_idle_s2idle, },
1442 	{
1443 		.name = "C6SP",
1444 		.desc = "MWAIT 0x23",
1445 		.flags = MWAIT2flg(0x23) | CPUIDLE_FLAG_TLB_FLUSHED |
1446 					   CPUIDLE_FLAG_PARTIAL_HINT_MATCH,
1447 		.exit_latency = 310,
1448 		.target_residency = 900,
1449 		.enter = intel_idle,
1450 		.enter_s2idle = intel_idle_s2idle, },
1451 	{
1452 		.enter = NULL }
1453 };
1454 
1455 static const struct idle_cpu idle_cpu_nehalem __initconst = {
1456 	.state_table = nehalem_cstates,
1457 	.auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
1458 	.disable_promotion_to_c1e = true,
1459 };
1460 
1461 static const struct idle_cpu idle_cpu_nhx __initconst = {
1462 	.state_table = nehalem_cstates,
1463 	.auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
1464 	.disable_promotion_to_c1e = true,
1465 	.use_acpi = true,
1466 };
1467 
1468 static const struct idle_cpu idle_cpu_atom __initconst = {
1469 	.state_table = atom_cstates,
1470 };
1471 
1472 static const struct idle_cpu idle_cpu_tangier __initconst = {
1473 	.state_table = tangier_cstates,
1474 };
1475 
1476 static const struct idle_cpu idle_cpu_lincroft __initconst = {
1477 	.state_table = atom_cstates,
1478 	.auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE,
1479 };
1480 
1481 static const struct idle_cpu idle_cpu_snb __initconst = {
1482 	.state_table = snb_cstates,
1483 	.disable_promotion_to_c1e = true,
1484 };
1485 
1486 static const struct idle_cpu idle_cpu_snx __initconst = {
1487 	.state_table = snb_cstates,
1488 	.disable_promotion_to_c1e = true,
1489 	.use_acpi = true,
1490 };
1491 
1492 static const struct idle_cpu idle_cpu_byt __initconst = {
1493 	.state_table = byt_cstates,
1494 	.disable_promotion_to_c1e = true,
1495 };
1496 
1497 static const struct idle_cpu idle_cpu_cht __initconst = {
1498 	.state_table = cht_cstates,
1499 	.disable_promotion_to_c1e = true,
1500 };
1501 
1502 static const struct idle_cpu idle_cpu_ivb __initconst = {
1503 	.state_table = ivb_cstates,
1504 	.disable_promotion_to_c1e = true,
1505 };
1506 
1507 static const struct idle_cpu idle_cpu_ivt __initconst = {
1508 	.state_table = ivt_cstates,
1509 	.disable_promotion_to_c1e = true,
1510 	.use_acpi = true,
1511 };
1512 
1513 static const struct idle_cpu idle_cpu_hsw __initconst = {
1514 	.state_table = hsw_cstates,
1515 	.disable_promotion_to_c1e = true,
1516 };
1517 
1518 static const struct idle_cpu idle_cpu_hsx __initconst = {
1519 	.state_table = hsw_cstates,
1520 	.disable_promotion_to_c1e = true,
1521 	.use_acpi = true,
1522 };
1523 
1524 static const struct idle_cpu idle_cpu_bdw __initconst = {
1525 	.state_table = bdw_cstates,
1526 	.disable_promotion_to_c1e = true,
1527 };
1528 
1529 static const struct idle_cpu idle_cpu_bdx __initconst = {
1530 	.state_table = bdw_cstates,
1531 	.disable_promotion_to_c1e = true,
1532 	.use_acpi = true,
1533 };
1534 
1535 static const struct idle_cpu idle_cpu_skl __initconst = {
1536 	.state_table = skl_cstates,
1537 	.disable_promotion_to_c1e = true,
1538 };
1539 
1540 static const struct idle_cpu idle_cpu_skx __initconst = {
1541 	.state_table = skx_cstates,
1542 	.disable_promotion_to_c1e = true,
1543 	.use_acpi = true,
1544 };
1545 
1546 static const struct idle_cpu idle_cpu_icx __initconst = {
1547 	.state_table = icx_cstates,
1548 	.disable_promotion_to_c1e = true,
1549 	.use_acpi = true,
1550 };
1551 
1552 static const struct idle_cpu idle_cpu_adl __initconst = {
1553 	.state_table = adl_cstates,
1554 };
1555 
1556 static const struct idle_cpu idle_cpu_adl_l __initconst = {
1557 	.state_table = adl_l_cstates,
1558 };
1559 
1560 static const struct idle_cpu idle_cpu_mtl_l __initconst = {
1561 	.state_table = mtl_l_cstates,
1562 };
1563 
1564 static const struct idle_cpu idle_cpu_gmt __initconst = {
1565 	.state_table = gmt_cstates,
1566 };
1567 
1568 static const struct idle_cpu idle_cpu_spr __initconst = {
1569 	.state_table = spr_cstates,
1570 	.disable_promotion_to_c1e = true,
1571 	.c1_demotion_supported = true,
1572 	.use_acpi = true,
1573 };
1574 
1575 static const struct idle_cpu idle_cpu_gnr __initconst = {
1576 	.state_table = gnr_cstates,
1577 	.disable_promotion_to_c1e = true,
1578 	.c1_demotion_supported = true,
1579 	.use_acpi = true,
1580 };
1581 
1582 static const struct idle_cpu idle_cpu_gnrd __initconst = {
1583 	.state_table = gnrd_cstates,
1584 	.disable_promotion_to_c1e = true,
1585 	.c1_demotion_supported = true,
1586 	.use_acpi = true,
1587 };
1588 
1589 static const struct idle_cpu idle_cpu_avn __initconst = {
1590 	.state_table = avn_cstates,
1591 	.disable_promotion_to_c1e = true,
1592 	.use_acpi = true,
1593 };
1594 
1595 static const struct idle_cpu idle_cpu_knl __initconst = {
1596 	.state_table = knl_cstates,
1597 	.use_acpi = true,
1598 };
1599 
1600 static const struct idle_cpu idle_cpu_bxt __initconst = {
1601 	.state_table = bxt_cstates,
1602 	.disable_promotion_to_c1e = true,
1603 };
1604 
1605 static const struct idle_cpu idle_cpu_dnv __initconst = {
1606 	.state_table = dnv_cstates,
1607 	.disable_promotion_to_c1e = true,
1608 	.use_acpi = true,
1609 };
1610 
1611 static const struct idle_cpu idle_cpu_tmt __initconst = {
1612 	.disable_promotion_to_c1e = true,
1613 };
1614 
1615 static const struct idle_cpu idle_cpu_snr __initconst = {
1616 	.state_table = snr_cstates,
1617 	.disable_promotion_to_c1e = true,
1618 	.use_acpi = true,
1619 };
1620 
1621 static const struct idle_cpu idle_cpu_grr __initconst = {
1622 	.state_table = grr_cstates,
1623 	.disable_promotion_to_c1e = true,
1624 	.c1_demotion_supported = true,
1625 	.use_acpi = true,
1626 };
1627 
1628 static const struct idle_cpu idle_cpu_srf __initconst = {
1629 	.state_table = srf_cstates,
1630 	.disable_promotion_to_c1e = true,
1631 	.c1_demotion_supported = true,
1632 	.use_acpi = true,
1633 };
1634 
1635 static const struct x86_cpu_id intel_idle_ids[] __initconst = {
1636 	X86_MATCH_VFM(INTEL_NEHALEM_EP,		&idle_cpu_nhx),
1637 	X86_MATCH_VFM(INTEL_NEHALEM,		&idle_cpu_nehalem),
1638 	X86_MATCH_VFM(INTEL_NEHALEM_G,		&idle_cpu_nehalem),
1639 	X86_MATCH_VFM(INTEL_WESTMERE,		&idle_cpu_nehalem),
1640 	X86_MATCH_VFM(INTEL_WESTMERE_EP,	&idle_cpu_nhx),
1641 	X86_MATCH_VFM(INTEL_NEHALEM_EX,		&idle_cpu_nhx),
1642 	X86_MATCH_VFM(INTEL_ATOM_BONNELL,	&idle_cpu_atom),
1643 	X86_MATCH_VFM(INTEL_ATOM_BONNELL_MID,	&idle_cpu_lincroft),
1644 	X86_MATCH_VFM(INTEL_WESTMERE_EX,	&idle_cpu_nhx),
1645 	X86_MATCH_VFM(INTEL_SANDYBRIDGE,	&idle_cpu_snb),
1646 	X86_MATCH_VFM(INTEL_SANDYBRIDGE_X,	&idle_cpu_snx),
1647 	X86_MATCH_VFM(INTEL_ATOM_SALTWELL,	&idle_cpu_atom),
1648 	X86_MATCH_VFM(INTEL_ATOM_SILVERMONT,	&idle_cpu_byt),
1649 	X86_MATCH_VFM(INTEL_ATOM_SILVERMONT_MID, &idle_cpu_tangier),
1650 	X86_MATCH_VFM(INTEL_ATOM_AIRMONT,	&idle_cpu_cht),
1651 	X86_MATCH_VFM(INTEL_IVYBRIDGE,		&idle_cpu_ivb),
1652 	X86_MATCH_VFM(INTEL_IVYBRIDGE_X,	&idle_cpu_ivt),
1653 	X86_MATCH_VFM(INTEL_HASWELL,		&idle_cpu_hsw),
1654 	X86_MATCH_VFM(INTEL_HASWELL_X,		&idle_cpu_hsx),
1655 	X86_MATCH_VFM(INTEL_HASWELL_L,		&idle_cpu_hsw),
1656 	X86_MATCH_VFM(INTEL_HASWELL_G,		&idle_cpu_hsw),
1657 	X86_MATCH_VFM(INTEL_ATOM_SILVERMONT_D,	&idle_cpu_avn),
1658 	X86_MATCH_VFM(INTEL_BROADWELL,		&idle_cpu_bdw),
1659 	X86_MATCH_VFM(INTEL_BROADWELL_G,	&idle_cpu_bdw),
1660 	X86_MATCH_VFM(INTEL_BROADWELL_X,	&idle_cpu_bdx),
1661 	X86_MATCH_VFM(INTEL_BROADWELL_D,	&idle_cpu_bdx),
1662 	X86_MATCH_VFM(INTEL_SKYLAKE_L,		&idle_cpu_skl),
1663 	X86_MATCH_VFM(INTEL_SKYLAKE,		&idle_cpu_skl),
1664 	X86_MATCH_VFM(INTEL_KABYLAKE_L,		&idle_cpu_skl),
1665 	X86_MATCH_VFM(INTEL_KABYLAKE,		&idle_cpu_skl),
1666 	X86_MATCH_VFM(INTEL_SKYLAKE_X,		&idle_cpu_skx),
1667 	X86_MATCH_VFM(INTEL_ICELAKE_X,		&idle_cpu_icx),
1668 	X86_MATCH_VFM(INTEL_ICELAKE_D,		&idle_cpu_icx),
1669 	X86_MATCH_VFM(INTEL_ALDERLAKE,		&idle_cpu_adl),
1670 	X86_MATCH_VFM(INTEL_ALDERLAKE_L,	&idle_cpu_adl_l),
1671 	X86_MATCH_VFM(INTEL_METEORLAKE_L,	&idle_cpu_mtl_l),
1672 	X86_MATCH_VFM(INTEL_ATOM_GRACEMONT,	&idle_cpu_gmt),
1673 	X86_MATCH_VFM(INTEL_SAPPHIRERAPIDS_X,	&idle_cpu_spr),
1674 	X86_MATCH_VFM(INTEL_EMERALDRAPIDS_X,	&idle_cpu_spr),
1675 	X86_MATCH_VFM(INTEL_GRANITERAPIDS_X,	&idle_cpu_gnr),
1676 	X86_MATCH_VFM(INTEL_GRANITERAPIDS_D,	&idle_cpu_gnrd),
1677 	X86_MATCH_VFM(INTEL_XEON_PHI_KNL,	&idle_cpu_knl),
1678 	X86_MATCH_VFM(INTEL_XEON_PHI_KNM,	&idle_cpu_knl),
1679 	X86_MATCH_VFM(INTEL_ATOM_GOLDMONT,	&idle_cpu_bxt),
1680 	X86_MATCH_VFM(INTEL_ATOM_GOLDMONT_PLUS,	&idle_cpu_bxt),
1681 	X86_MATCH_VFM(INTEL_ATOM_GOLDMONT_D,	&idle_cpu_dnv),
1682 	X86_MATCH_VFM(INTEL_ATOM_TREMONT,       &idle_cpu_tmt),
1683 	X86_MATCH_VFM(INTEL_ATOM_TREMONT_L,     &idle_cpu_tmt),
1684 	X86_MATCH_VFM(INTEL_ATOM_TREMONT_D,	&idle_cpu_snr),
1685 	X86_MATCH_VFM(INTEL_ATOM_CRESTMONT,	&idle_cpu_grr),
1686 	X86_MATCH_VFM(INTEL_ATOM_CRESTMONT_X,	&idle_cpu_srf),
1687 	X86_MATCH_VFM(INTEL_ATOM_DARKMONT_X,	&idle_cpu_srf),
1688 	{}
1689 };
1690 
1691 static const struct x86_cpu_id intel_mwait_ids[] __initconst = {
1692 	X86_MATCH_VENDOR_FAM_FEATURE(INTEL, X86_FAMILY_ANY, X86_FEATURE_MWAIT, NULL),
1693 	{}
1694 };
1695 
1696 static bool __init intel_idle_max_cstate_reached(int cstate)
1697 {
1698 	if (cstate + 1 > max_cstate) {
1699 		pr_info("max_cstate %d reached\n", max_cstate);
1700 		return true;
1701 	}
1702 	return false;
1703 }
1704 
1705 static bool __init intel_idle_state_needs_timer_stop(struct cpuidle_state *state)
1706 {
1707 	unsigned long eax = flg2MWAIT(state->flags);
1708 
1709 	if (boot_cpu_has(X86_FEATURE_ARAT))
1710 		return false;
1711 
1712 	/*
1713 	 * Switch over to one-shot tick broadcast if the target C-state
1714 	 * is deeper than C1.
1715 	 */
1716 	return !!((eax >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK);
1717 }
1718 
1719 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
1720 #include <acpi/processor.h>
1721 
1722 static bool no_acpi __read_mostly;
1723 module_param(no_acpi, bool, 0444);
1724 MODULE_PARM_DESC(no_acpi, "Do not use ACPI _CST for building the idle states list");
1725 
1726 static bool force_use_acpi __read_mostly; /* No effect if no_acpi is set. */
1727 module_param_named(use_acpi, force_use_acpi, bool, 0444);
1728 MODULE_PARM_DESC(use_acpi, "Use ACPI _CST for building the idle states list");
1729 
1730 static bool no_native __read_mostly; /* No effect if no_acpi is set. */
1731 module_param_named(no_native, no_native, bool, 0444);
1732 MODULE_PARM_DESC(no_native, "Ignore cpu specific (native) idle states in lieu of ACPI idle states");
1733 
1734 static struct acpi_processor_power acpi_state_table __initdata;
1735 
1736 /**
1737  * intel_idle_cst_usable - Check if the _CST information can be used.
1738  *
1739  * Check if all of the C-states listed by _CST in the max_cstate range are
1740  * ACPI_CSTATE_FFH, which means that they should be entered via MWAIT.
1741  */
1742 static bool __init intel_idle_cst_usable(void)
1743 {
1744 	int cstate, limit;
1745 
1746 	limit = min_t(int, min_t(int, CPUIDLE_STATE_MAX, max_cstate + 1),
1747 		      acpi_state_table.count);
1748 
1749 	for (cstate = 1; cstate < limit; cstate++) {
1750 		struct acpi_processor_cx *cx = &acpi_state_table.states[cstate];
1751 
1752 		if (cx->entry_method != ACPI_CSTATE_FFH)
1753 			return false;
1754 	}
1755 
1756 	return true;
1757 }
1758 
1759 static bool __init intel_idle_acpi_cst_extract(void)
1760 {
1761 	unsigned int cpu;
1762 
1763 	if (no_acpi) {
1764 		pr_debug("Not allowed to use ACPI _CST\n");
1765 		return false;
1766 	}
1767 
1768 	for_each_possible_cpu(cpu) {
1769 		struct acpi_processor *pr = per_cpu(processors, cpu);
1770 
1771 		if (!pr)
1772 			continue;
1773 
1774 		if (acpi_processor_evaluate_cst(pr->handle, cpu, &acpi_state_table))
1775 			continue;
1776 
1777 		acpi_state_table.count++;
1778 
1779 		if (!intel_idle_cst_usable())
1780 			continue;
1781 
1782 		if (!acpi_processor_claim_cst_control())
1783 			break;
1784 
1785 		return true;
1786 	}
1787 
1788 	acpi_state_table.count = 0;
1789 	pr_debug("ACPI _CST not found or not usable\n");
1790 	return false;
1791 }
1792 
1793 static void __init intel_idle_init_cstates_acpi(struct cpuidle_driver *drv)
1794 {
1795 	int cstate, limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1796 
1797 	/*
1798 	 * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1799 	 * the interesting states are ACPI_CSTATE_FFH.
1800 	 */
1801 	for (cstate = 1; cstate < limit; cstate++) {
1802 		struct acpi_processor_cx *cx;
1803 		struct cpuidle_state *state;
1804 
1805 		if (intel_idle_max_cstate_reached(cstate - 1))
1806 			break;
1807 
1808 		cx = &acpi_state_table.states[cstate];
1809 
1810 		state = &drv->states[drv->state_count++];
1811 
1812 		snprintf(state->name, CPUIDLE_NAME_LEN, "C%d_ACPI", cstate);
1813 		strscpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
1814 		state->exit_latency = cx->latency;
1815 		/*
1816 		 * For C1-type C-states use the same number for both the exit
1817 		 * latency and target residency, because that is the case for
1818 		 * C1 in the majority of the static C-states tables above.
1819 		 * For the other types of C-states, however, set the target
1820 		 * residency to 3 times the exit latency which should lead to
1821 		 * a reasonable balance between energy-efficiency and
1822 		 * performance in the majority of interesting cases.
1823 		 */
1824 		state->target_residency = cx->latency;
1825 		if (cx->type > ACPI_STATE_C1)
1826 			state->target_residency *= 3;
1827 
1828 		state->flags = MWAIT2flg(cx->address);
1829 		if (cx->type > ACPI_STATE_C2)
1830 			state->flags |= CPUIDLE_FLAG_TLB_FLUSHED;
1831 
1832 		if (disabled_states_mask & BIT(cstate))
1833 			state->flags |= CPUIDLE_FLAG_OFF;
1834 
1835 		if (intel_idle_state_needs_timer_stop(state))
1836 			state->flags |= CPUIDLE_FLAG_TIMER_STOP;
1837 
1838 		if (cx->type > ACPI_STATE_C1 && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
1839 			mark_tsc_unstable("TSC halts in idle");
1840 
1841 		state->enter = intel_idle;
1842 		state->enter_dead = intel_idle_enter_dead;
1843 		state->enter_s2idle = intel_idle_s2idle;
1844 	}
1845 }
1846 
1847 static bool __init intel_idle_off_by_default(unsigned int flags, u32 mwait_hint)
1848 {
1849 	int cstate, limit;
1850 
1851 	/*
1852 	 * If there are no _CST C-states, do not disable any C-states by
1853 	 * default.
1854 	 */
1855 	if (!acpi_state_table.count)
1856 		return false;
1857 
1858 	limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1859 	/*
1860 	 * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1861 	 * the interesting states are ACPI_CSTATE_FFH.
1862 	 */
1863 	for (cstate = 1; cstate < limit; cstate++) {
1864 		u32 acpi_hint = acpi_state_table.states[cstate].address;
1865 		u32 table_hint = mwait_hint;
1866 
1867 		if (flags & CPUIDLE_FLAG_PARTIAL_HINT_MATCH) {
1868 			acpi_hint &= ~MWAIT_SUBSTATE_MASK;
1869 			table_hint &= ~MWAIT_SUBSTATE_MASK;
1870 		}
1871 
1872 		if (acpi_hint == table_hint)
1873 			return false;
1874 	}
1875 	return true;
1876 }
1877 
1878 static inline bool ignore_native(void)
1879 {
1880 	return no_native && !no_acpi;
1881 }
1882 #else /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1883 #define force_use_acpi	(false)
1884 
1885 static inline bool intel_idle_acpi_cst_extract(void) { return false; }
1886 static inline void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { }
1887 static inline bool intel_idle_off_by_default(unsigned int flags, u32 mwait_hint)
1888 {
1889 	return false;
1890 }
1891 static inline bool ignore_native(void) { return false; }
1892 #endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1893 
1894 /**
1895  * ivt_idle_state_table_update - Tune the idle states table for Ivy Town.
1896  *
1897  * Tune IVT multi-socket targets.
1898  * Assumption: num_sockets == (max_package_num + 1).
1899  */
1900 static void __init ivt_idle_state_table_update(void)
1901 {
1902 	/* IVT uses a different table for 1-2, 3-4, and > 4 sockets */
1903 	int cpu, package_num, num_sockets = 1;
1904 
1905 	for_each_online_cpu(cpu) {
1906 		package_num = topology_physical_package_id(cpu);
1907 		if (package_num + 1 > num_sockets) {
1908 			num_sockets = package_num + 1;
1909 
1910 			if (num_sockets > 4) {
1911 				cpuidle_state_table = ivt_cstates_8s;
1912 				return;
1913 			}
1914 		}
1915 	}
1916 
1917 	if (num_sockets > 2)
1918 		cpuidle_state_table = ivt_cstates_4s;
1919 
1920 	/* else, 1 and 2 socket systems use default ivt_cstates */
1921 }
1922 
1923 /**
1924  * irtl_2_usec - IRTL to microseconds conversion.
1925  * @irtl: IRTL MSR value.
1926  *
1927  * Translate the IRTL (Interrupt Response Time Limit) MSR value to microseconds.
1928  */
1929 static unsigned long long __init irtl_2_usec(unsigned long long irtl)
1930 {
1931 	static const unsigned int irtl_ns_units[] __initconst = {
1932 		1, 32, 1024, 32768, 1048576, 33554432, 0, 0
1933 	};
1934 	unsigned long long ns;
1935 
1936 	if (!irtl)
1937 		return 0;
1938 
1939 	ns = irtl_ns_units[(irtl >> 10) & 0x7];
1940 
1941 	return div_u64((irtl & 0x3FF) * ns, NSEC_PER_USEC);
1942 }
1943 
1944 /**
1945  * bxt_idle_state_table_update - Fix up the Broxton idle states table.
1946  *
1947  * On BXT, trust the IRTL (Interrupt Response Time Limit) MSR to show the
1948  * definitive maximum latency and use the same value for target_residency.
1949  */
1950 static void __init bxt_idle_state_table_update(void)
1951 {
1952 	unsigned long long msr;
1953 	unsigned int usec;
1954 
1955 	rdmsrq(MSR_PKGC6_IRTL, msr);
1956 	usec = irtl_2_usec(msr);
1957 	if (usec) {
1958 		bxt_cstates[2].exit_latency = usec;
1959 		bxt_cstates[2].target_residency = usec;
1960 	}
1961 
1962 	rdmsrq(MSR_PKGC7_IRTL, msr);
1963 	usec = irtl_2_usec(msr);
1964 	if (usec) {
1965 		bxt_cstates[3].exit_latency = usec;
1966 		bxt_cstates[3].target_residency = usec;
1967 	}
1968 
1969 	rdmsrq(MSR_PKGC8_IRTL, msr);
1970 	usec = irtl_2_usec(msr);
1971 	if (usec) {
1972 		bxt_cstates[4].exit_latency = usec;
1973 		bxt_cstates[4].target_residency = usec;
1974 	}
1975 
1976 	rdmsrq(MSR_PKGC9_IRTL, msr);
1977 	usec = irtl_2_usec(msr);
1978 	if (usec) {
1979 		bxt_cstates[5].exit_latency = usec;
1980 		bxt_cstates[5].target_residency = usec;
1981 	}
1982 
1983 	rdmsrq(MSR_PKGC10_IRTL, msr);
1984 	usec = irtl_2_usec(msr);
1985 	if (usec) {
1986 		bxt_cstates[6].exit_latency = usec;
1987 		bxt_cstates[6].target_residency = usec;
1988 	}
1989 
1990 }
1991 
1992 /**
1993  * sklh_idle_state_table_update - Fix up the Sky Lake idle states table.
1994  *
1995  * On SKL-H (model 0x5e) skip C8 and C9 if C10 is enabled and SGX disabled.
1996  */
1997 static void __init sklh_idle_state_table_update(void)
1998 {
1999 	unsigned long long msr;
2000 	unsigned int eax, ebx, ecx, edx;
2001 
2002 
2003 	/* if PC10 disabled via cmdline intel_idle.max_cstate=7 or shallower */
2004 	if (max_cstate <= 7)
2005 		return;
2006 
2007 	/* if PC10 not present in CPUID.MWAIT.EDX */
2008 	if ((mwait_substates & (0xF << 28)) == 0)
2009 		return;
2010 
2011 	rdmsrq(MSR_PKG_CST_CONFIG_CONTROL, msr);
2012 
2013 	/* PC10 is not enabled in PKG C-state limit */
2014 	if ((msr & 0xF) != 8)
2015 		return;
2016 
2017 	ecx = 0;
2018 	cpuid(7, &eax, &ebx, &ecx, &edx);
2019 
2020 	/* if SGX is present */
2021 	if (ebx & (1 << 2)) {
2022 
2023 		rdmsrq(MSR_IA32_FEAT_CTL, msr);
2024 
2025 		/* if SGX is enabled */
2026 		if (msr & (1 << 18))
2027 			return;
2028 	}
2029 
2030 	skl_cstates[5].flags |= CPUIDLE_FLAG_UNUSABLE;	/* C8-SKL */
2031 	skl_cstates[6].flags |= CPUIDLE_FLAG_UNUSABLE;	/* C9-SKL */
2032 }
2033 
2034 /**
2035  * skx_idle_state_table_update - Adjust the Sky Lake/Cascade Lake
2036  * idle states table.
2037  */
2038 static void __init skx_idle_state_table_update(void)
2039 {
2040 	unsigned long long msr;
2041 
2042 	rdmsrq(MSR_PKG_CST_CONFIG_CONTROL, msr);
2043 
2044 	/*
2045 	 * 000b: C0/C1 (no package C-state support)
2046 	 * 001b: C2
2047 	 * 010b: C6 (non-retention)
2048 	 * 011b: C6 (retention)
2049 	 * 111b: No Package C state limits.
2050 	 */
2051 	if ((msr & 0x7) < 2) {
2052 		/*
2053 		 * Uses the CC6 + PC0 latency and 3 times of
2054 		 * latency for target_residency if the PC6
2055 		 * is disabled in BIOS. This is consistent
2056 		 * with how intel_idle driver uses _CST
2057 		 * to set the target_residency.
2058 		 */
2059 		skx_cstates[2].exit_latency = 92;
2060 		skx_cstates[2].target_residency = 276;
2061 	}
2062 }
2063 
2064 /**
2065  * spr_idle_state_table_update - Adjust Sapphire Rapids idle states table.
2066  */
2067 static void __init spr_idle_state_table_update(void)
2068 {
2069 	unsigned long long msr;
2070 
2071 	/*
2072 	 * By default, the C6 state assumes the worst-case scenario of package
2073 	 * C6. However, if PC6 is disabled, we update the numbers to match
2074 	 * core C6.
2075 	 */
2076 	rdmsrq(MSR_PKG_CST_CONFIG_CONTROL, msr);
2077 
2078 	/* Limit value 2 and above allow for PC6. */
2079 	if ((msr & 0x7) < 2) {
2080 		spr_cstates[2].exit_latency = 190;
2081 		spr_cstates[2].target_residency = 600;
2082 	}
2083 }
2084 
2085 /**
2086  * byt_cht_auto_demotion_disable - Disable Bay/Cherry Trail auto-demotion.
2087  */
2088 static void __init byt_cht_auto_demotion_disable(void)
2089 {
2090 	wrmsrq(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
2091 	wrmsrq(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
2092 }
2093 
2094 static bool __init intel_idle_verify_cstate(unsigned int mwait_hint)
2095 {
2096 	unsigned int mwait_cstate = (MWAIT_HINT2CSTATE(mwait_hint) + 1) &
2097 					MWAIT_CSTATE_MASK;
2098 	unsigned int num_substates = (mwait_substates >> mwait_cstate * 4) &
2099 					MWAIT_SUBSTATE_MASK;
2100 
2101 	/* Ignore the C-state if there are NO sub-states in CPUID for it. */
2102 	if (num_substates == 0)
2103 		return false;
2104 
2105 	if (mwait_cstate > 2 && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
2106 		mark_tsc_unstable("TSC halts in idle states deeper than C2");
2107 
2108 	return true;
2109 }
2110 
2111 static void state_update_enter_method(struct cpuidle_state *state, int cstate)
2112 {
2113 	if (state->flags & CPUIDLE_FLAG_INIT_XSTATE) {
2114 		/*
2115 		 * Combining with XSTATE with IBRS or IRQ_ENABLE flags
2116 		 * is not currently supported but this driver.
2117 		 */
2118 		WARN_ON_ONCE(state->flags & CPUIDLE_FLAG_IBRS);
2119 		WARN_ON_ONCE(state->flags & CPUIDLE_FLAG_IRQ_ENABLE);
2120 		state->enter = intel_idle_xstate;
2121 		return;
2122 	}
2123 
2124 	if (cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS) &&
2125 			((state->flags & CPUIDLE_FLAG_IBRS) || ibrs_off)) {
2126 		/*
2127 		 * IBRS mitigation requires that C-states are entered
2128 		 * with interrupts disabled.
2129 		 */
2130 		if (ibrs_off && (state->flags & CPUIDLE_FLAG_IRQ_ENABLE))
2131 			state->flags &= ~CPUIDLE_FLAG_IRQ_ENABLE;
2132 		WARN_ON_ONCE(state->flags & CPUIDLE_FLAG_IRQ_ENABLE);
2133 		state->enter = intel_idle_ibrs;
2134 		return;
2135 	}
2136 
2137 	if (state->flags & CPUIDLE_FLAG_IRQ_ENABLE) {
2138 		state->enter = intel_idle_irq;
2139 		return;
2140 	}
2141 
2142 	if (force_irq_on) {
2143 		pr_info("forced intel_idle_irq for state %d\n", cstate);
2144 		state->enter = intel_idle_irq;
2145 	}
2146 }
2147 
2148 static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
2149 {
2150 	int cstate;
2151 
2152 	switch (boot_cpu_data.x86_vfm) {
2153 	case INTEL_IVYBRIDGE_X:
2154 		ivt_idle_state_table_update();
2155 		break;
2156 	case INTEL_ATOM_GOLDMONT:
2157 	case INTEL_ATOM_GOLDMONT_PLUS:
2158 		bxt_idle_state_table_update();
2159 		break;
2160 	case INTEL_SKYLAKE:
2161 		sklh_idle_state_table_update();
2162 		break;
2163 	case INTEL_SKYLAKE_X:
2164 		skx_idle_state_table_update();
2165 		break;
2166 	case INTEL_SAPPHIRERAPIDS_X:
2167 	case INTEL_EMERALDRAPIDS_X:
2168 		spr_idle_state_table_update();
2169 		break;
2170 	case INTEL_ATOM_SILVERMONT:
2171 	case INTEL_ATOM_AIRMONT:
2172 		byt_cht_auto_demotion_disable();
2173 		break;
2174 	}
2175 
2176 	for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
2177 		struct cpuidle_state *state;
2178 		unsigned int mwait_hint;
2179 
2180 		if (intel_idle_max_cstate_reached(cstate))
2181 			break;
2182 
2183 		if (!cpuidle_state_table[cstate].enter &&
2184 		    !cpuidle_state_table[cstate].enter_s2idle)
2185 			break;
2186 
2187 		if (!cpuidle_state_table[cstate].enter_dead)
2188 			cpuidle_state_table[cstate].enter_dead = intel_idle_enter_dead;
2189 
2190 		/* If marked as unusable, skip this state. */
2191 		if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_UNUSABLE) {
2192 			pr_debug("state %s is disabled\n",
2193 				 cpuidle_state_table[cstate].name);
2194 			continue;
2195 		}
2196 
2197 		mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags);
2198 		if (!intel_idle_verify_cstate(mwait_hint))
2199 			continue;
2200 
2201 		/* Structure copy. */
2202 		drv->states[drv->state_count] = cpuidle_state_table[cstate];
2203 		state = &drv->states[drv->state_count];
2204 
2205 		state_update_enter_method(state, cstate);
2206 
2207 
2208 		if ((disabled_states_mask & BIT(drv->state_count)) ||
2209 		    ((icpu->use_acpi || force_use_acpi) &&
2210 		     intel_idle_off_by_default(state->flags, mwait_hint) &&
2211 		     !(state->flags & CPUIDLE_FLAG_ALWAYS_ENABLE)))
2212 			state->flags |= CPUIDLE_FLAG_OFF;
2213 
2214 		if (intel_idle_state_needs_timer_stop(state))
2215 			state->flags |= CPUIDLE_FLAG_TIMER_STOP;
2216 
2217 		drv->state_count++;
2218 	}
2219 }
2220 
2221 /**
2222  * intel_idle_cpuidle_driver_init - Create the list of available idle states.
2223  * @drv: cpuidle driver structure to initialize.
2224  */
2225 static void __init intel_idle_cpuidle_driver_init(struct cpuidle_driver *drv)
2226 {
2227 	cpuidle_poll_state_init(drv);
2228 
2229 	if (disabled_states_mask & BIT(0))
2230 		drv->states[0].flags |= CPUIDLE_FLAG_OFF;
2231 
2232 	drv->state_count = 1;
2233 
2234 	if (icpu && icpu->state_table)
2235 		intel_idle_init_cstates_icpu(drv);
2236 	else
2237 		intel_idle_init_cstates_acpi(drv);
2238 }
2239 
2240 static void auto_demotion_disable(void)
2241 {
2242 	unsigned long long msr_bits;
2243 
2244 	rdmsrq(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
2245 	msr_bits &= ~auto_demotion_disable_flags;
2246 	wrmsrq(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
2247 }
2248 
2249 static void c1e_promotion_enable(void)
2250 {
2251 	unsigned long long msr_bits;
2252 
2253 	rdmsrq(MSR_IA32_POWER_CTL, msr_bits);
2254 	msr_bits |= 0x2;
2255 	wrmsrq(MSR_IA32_POWER_CTL, msr_bits);
2256 }
2257 
2258 static void c1e_promotion_disable(void)
2259 {
2260 	unsigned long long msr_bits;
2261 
2262 	rdmsrq(MSR_IA32_POWER_CTL, msr_bits);
2263 	msr_bits &= ~0x2;
2264 	wrmsrq(MSR_IA32_POWER_CTL, msr_bits);
2265 }
2266 
2267 /**
2268  * intel_idle_cpu_init - Register the target CPU with the cpuidle core.
2269  * @cpu: CPU to initialize.
2270  *
2271  * Register a cpuidle device object for @cpu and update its MSRs in accordance
2272  * with the processor model flags.
2273  */
2274 static int intel_idle_cpu_init(unsigned int cpu)
2275 {
2276 	struct cpuidle_device *dev;
2277 
2278 	dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
2279 	dev->cpu = cpu;
2280 
2281 	if (cpuidle_register_device(dev)) {
2282 		pr_debug("cpuidle_register_device %d failed!\n", cpu);
2283 		return -EIO;
2284 	}
2285 
2286 	if (auto_demotion_disable_flags)
2287 		auto_demotion_disable();
2288 
2289 	if (c1e_promotion == C1E_PROMOTION_ENABLE)
2290 		c1e_promotion_enable();
2291 	else if (c1e_promotion == C1E_PROMOTION_DISABLE)
2292 		c1e_promotion_disable();
2293 
2294 	return 0;
2295 }
2296 
2297 static int intel_idle_cpu_online(unsigned int cpu)
2298 {
2299 	struct cpuidle_device *dev;
2300 
2301 	if (!boot_cpu_has(X86_FEATURE_ARAT))
2302 		tick_broadcast_enable();
2303 
2304 	/*
2305 	 * Some systems can hotplug a cpu at runtime after
2306 	 * the kernel has booted, we have to initialize the
2307 	 * driver in this case
2308 	 */
2309 	dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
2310 	if (!dev->registered)
2311 		return intel_idle_cpu_init(cpu);
2312 
2313 	return 0;
2314 }
2315 
2316 /**
2317  * intel_idle_cpuidle_devices_uninit - Unregister all cpuidle devices.
2318  */
2319 static void __init intel_idle_cpuidle_devices_uninit(void)
2320 {
2321 	int i;
2322 
2323 	for_each_online_cpu(i)
2324 		cpuidle_unregister_device(per_cpu_ptr(intel_idle_cpuidle_devices, i));
2325 }
2326 
2327 static void intel_c1_demotion_toggle(void *enable)
2328 {
2329 	unsigned long long msr_val;
2330 
2331 	rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_val);
2332 	/*
2333 	 * Enable/disable C1 undemotion along with C1 demotion, as this is the
2334 	 * most sensible configuration in general.
2335 	 */
2336 	if (enable)
2337 		msr_val |= NHM_C1_AUTO_DEMOTE | SNB_C1_AUTO_UNDEMOTE;
2338 	else
2339 		msr_val &= ~(NHM_C1_AUTO_DEMOTE | SNB_C1_AUTO_UNDEMOTE);
2340 	wrmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_val);
2341 }
2342 
2343 static ssize_t intel_c1_demotion_store(struct device *dev,
2344 				       struct device_attribute *attr,
2345 				       const char *buf, size_t count)
2346 {
2347 	bool enable;
2348 	int err;
2349 
2350 	err = kstrtobool(buf, &enable);
2351 	if (err)
2352 		return err;
2353 
2354 	mutex_lock(&c1_demotion_mutex);
2355 	/* Enable/disable C1 demotion on all CPUs */
2356 	on_each_cpu(intel_c1_demotion_toggle, (void *)enable, 1);
2357 	mutex_unlock(&c1_demotion_mutex);
2358 
2359 	return count;
2360 }
2361 
2362 static ssize_t intel_c1_demotion_show(struct device *dev,
2363 				      struct device_attribute *attr, char *buf)
2364 {
2365 	unsigned long long msr_val;
2366 
2367 	/*
2368 	 * Read the MSR value for a CPU and assume it is the same for all CPUs. Any other
2369 	 * configuration would be a BIOS bug.
2370 	 */
2371 	rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_val);
2372 	return sysfs_emit(buf, "%d\n", !!(msr_val & NHM_C1_AUTO_DEMOTE));
2373 }
2374 static DEVICE_ATTR_RW(intel_c1_demotion);
2375 
2376 static int __init intel_idle_sysfs_init(void)
2377 {
2378 	int err;
2379 
2380 	if (!c1_demotion_supported)
2381 		return 0;
2382 
2383 	sysfs_root = bus_get_dev_root(&cpu_subsys);
2384 	if (!sysfs_root)
2385 		return 0;
2386 
2387 	err = sysfs_add_file_to_group(&sysfs_root->kobj,
2388 				      &dev_attr_intel_c1_demotion.attr,
2389 				      "cpuidle");
2390 	if (err) {
2391 		put_device(sysfs_root);
2392 		return err;
2393 	}
2394 
2395 	return 0;
2396 }
2397 
2398 static void __init intel_idle_sysfs_uninit(void)
2399 {
2400 	if (!sysfs_root)
2401 		return;
2402 
2403 	sysfs_remove_file_from_group(&sysfs_root->kobj,
2404 				     &dev_attr_intel_c1_demotion.attr,
2405 				     "cpuidle");
2406 	put_device(sysfs_root);
2407 }
2408 
2409  /**
2410   * get_cmdline_field - Get the current field from a cmdline string.
2411   * @args: The cmdline string to get the current field from.
2412   * @field: Pointer to the current field upon return.
2413   * @sep: The fields separator character.
2414   *
2415   * Examples:
2416   *   Input: args="C1:1:1,C1E:2:10", sep=':'
2417   *   Output: field="C1", return "1:1,C1E:2:10"
2418   *   Input: args="C1:1:1,C1E:2:10", sep=','
2419   *   Output: field="C1:1:1", return "C1E:2:10"
2420   *   Ipnut: args="::", sep=':'
2421   *   Output: field="", return ":"
2422   *
2423   * Return: The continuation of the cmdline string after the field or NULL.
2424   */
2425 static char *get_cmdline_field(char *args, char **field, char sep)
2426 {
2427 	unsigned int i;
2428 
2429 	for (i = 0; args[i] && !isspace(args[i]); i++) {
2430 		if (args[i] == sep)
2431 			break;
2432 	}
2433 
2434 	*field = args;
2435 
2436 	if (args[i] != sep)
2437 		return NULL;
2438 
2439 	args[i] = '\0';
2440 	return args + i + 1;
2441 }
2442 
2443 /**
2444  * validate_cmdline_cstate - Validate a C-state from cmdline.
2445  * @state: The C-state to validate.
2446  * @prev_state: The previous C-state in the table or NULL.
2447  *
2448  * Return: 0 if the C-state is valid or -EINVAL otherwise.
2449  */
2450 static int validate_cmdline_cstate(struct cpuidle_state *state,
2451 				   struct cpuidle_state *prev_state)
2452 {
2453 	if (state->exit_latency == 0)
2454 		/* Exit latency 0 can only be used for the POLL state */
2455 		return -EINVAL;
2456 
2457 	if (state->exit_latency > MAX_CMDLINE_LATENCY_US)
2458 		return -EINVAL;
2459 
2460 	if (state->target_residency > MAX_CMDLINE_RESIDENCY_US)
2461 		return -EINVAL;
2462 
2463 	if (state->target_residency < state->exit_latency)
2464 		return -EINVAL;
2465 
2466 	if (!prev_state)
2467 		return 0;
2468 
2469 	if (state->exit_latency <= prev_state->exit_latency)
2470 		return -EINVAL;
2471 
2472 	if (state->target_residency <= prev_state->target_residency)
2473 		return -EINVAL;
2474 
2475 	return 0;
2476 }
2477 
2478 /**
2479  * cmdline_table_adjust - Adjust the C-states table with data from cmdline.
2480  * @drv: cpuidle driver (assumed to point to intel_idle_driver).
2481  *
2482  * Adjust the C-states table with data from the 'intel_idle.table' module
2483  * parameter (if specified).
2484  */
2485 static void __init cmdline_table_adjust(struct cpuidle_driver *drv)
2486 {
2487 	char *args = cmdline_table_str;
2488 	struct cpuidle_state *state;
2489 	int i;
2490 
2491 	if (args[0] == '\0')
2492 		/* The 'intel_idle.table' module parameter was not specified */
2493 		return;
2494 
2495 	/* Create a copy of the C-states table */
2496 	for (i = 0; i < drv->state_count; i++)
2497 		cmdline_states[i] = drv->states[i];
2498 
2499 	/*
2500 	 * Adjust the C-states table copy with data from the 'intel_idle.table'
2501 	 * module parameter.
2502 	 */
2503 	while (args) {
2504 		char *fields, *name, *val;
2505 
2506 		/*
2507 		 * Get the next C-state definition, which is expected to be
2508 		 * '<name>:<latency_us>:<target_residency_us>'. Treat "empty"
2509 		 * fields as unchanged. For example,
2510 		 * '<name>::<target_residency_us>' leaves the latency unchanged.
2511 		 */
2512 		args = get_cmdline_field(args, &fields, ',');
2513 
2514 		/* name */
2515 		fields = get_cmdline_field(fields, &name, ':');
2516 		if (!fields)
2517 			goto error;
2518 
2519 		if (!strcmp(name, "POLL")) {
2520 			pr_err("Cannot adjust POLL\n");
2521 			continue;
2522 		}
2523 
2524 		/* Find the C-state by its name */
2525 		state = NULL;
2526 		for (i = 0; i < drv->state_count; i++) {
2527 			if (!strcmp(name, drv->states[i].name)) {
2528 				state = &cmdline_states[i];
2529 				break;
2530 			}
2531 		}
2532 
2533 		if (!state) {
2534 			pr_err("C-state '%s' was not found\n", name);
2535 			continue;
2536 		}
2537 
2538 		/* Latency */
2539 		fields = get_cmdline_field(fields, &val, ':');
2540 		if (!fields)
2541 			goto error;
2542 
2543 		if (*val) {
2544 			if (kstrtouint(val, 0, &state->exit_latency))
2545 				goto error;
2546 		}
2547 
2548 		/* Target residency */
2549 		fields = get_cmdline_field(fields, &val, ':');
2550 
2551 		if (*val) {
2552 			if (kstrtouint(val, 0, &state->target_residency))
2553 				goto error;
2554 		}
2555 
2556 		/*
2557 		 * Allow for 3 more fields, but ignore them. Helps to make
2558 		 * possible future extensions of the cmdline format backward
2559 		 * compatible.
2560 		 */
2561 		for (i = 0; fields && i < 3; i++) {
2562 			fields = get_cmdline_field(fields, &val, ':');
2563 			if (!fields)
2564 				break;
2565 		}
2566 
2567 		if (fields) {
2568 			pr_err("Too many fields for C-state '%s'\n", state->name);
2569 			goto error;
2570 		}
2571 
2572 		pr_info("C-state from cmdline: name=%s, latency=%u, residency=%u\n",
2573 			state->name, state->exit_latency, state->target_residency);
2574 	}
2575 
2576 	/* Validate the adjusted C-states, start with index 1 to skip POLL */
2577 	for (i = 1; i < drv->state_count; i++) {
2578 		struct cpuidle_state *prev_state;
2579 
2580 		state = &cmdline_states[i];
2581 		prev_state = &cmdline_states[i - 1];
2582 
2583 		if (validate_cmdline_cstate(state, prev_state)) {
2584 			pr_err("C-state '%s' validation failed\n", state->name);
2585 			goto error;
2586 		}
2587 	}
2588 
2589 	/* Copy the adjusted C-states table back */
2590 	for (i = 1; i < drv->state_count; i++)
2591 		drv->states[i] = cmdline_states[i];
2592 
2593 	pr_info("Adjusted C-states with data from 'intel_idle.table'\n");
2594 	return;
2595 
2596 error:
2597 	pr_info("Failed to adjust C-states with data from 'intel_idle.table'\n");
2598 }
2599 
2600 static int __init intel_idle_init(void)
2601 {
2602 	const struct x86_cpu_id *id;
2603 	unsigned int eax, ebx, ecx;
2604 	int retval;
2605 
2606 	/* Do not load intel_idle at all for now if idle= is passed */
2607 	if (boot_option_idle_override != IDLE_NO_OVERRIDE)
2608 		return -ENODEV;
2609 
2610 	if (max_cstate == 0) {
2611 		pr_debug("disabled\n");
2612 		return -EPERM;
2613 	}
2614 
2615 	id = x86_match_cpu(intel_idle_ids);
2616 	if (id) {
2617 		if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
2618 			pr_debug("Please enable MWAIT in BIOS SETUP\n");
2619 			return -ENODEV;
2620 		}
2621 	} else {
2622 		id = x86_match_cpu(intel_mwait_ids);
2623 		if (!id)
2624 			return -ENODEV;
2625 	}
2626 
2627 	cpuid(CPUID_LEAF_MWAIT, &eax, &ebx, &ecx, &mwait_substates);
2628 
2629 	if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
2630 	    !(ecx & CPUID5_ECX_INTERRUPT_BREAK) ||
2631 	    !mwait_substates)
2632 			return -ENODEV;
2633 
2634 	pr_debug("MWAIT substates: 0x%x\n", mwait_substates);
2635 
2636 	icpu = (const struct idle_cpu *)id->driver_data;
2637 	if (icpu && ignore_native()) {
2638 		pr_debug("ignoring native CPU idle states\n");
2639 		icpu = NULL;
2640 	}
2641 	if (icpu) {
2642 		if (icpu->state_table)
2643 			cpuidle_state_table = icpu->state_table;
2644 		else if (!intel_idle_acpi_cst_extract())
2645 			return -ENODEV;
2646 
2647 		auto_demotion_disable_flags = icpu->auto_demotion_disable_flags;
2648 		if (icpu->disable_promotion_to_c1e)
2649 			c1e_promotion = C1E_PROMOTION_DISABLE;
2650 		if (icpu->c1_demotion_supported)
2651 			c1_demotion_supported = true;
2652 		if (icpu->use_acpi || force_use_acpi)
2653 			intel_idle_acpi_cst_extract();
2654 	} else if (!intel_idle_acpi_cst_extract()) {
2655 		return -ENODEV;
2656 	}
2657 
2658 	intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
2659 	if (!intel_idle_cpuidle_devices)
2660 		return -ENOMEM;
2661 
2662 	intel_idle_cpuidle_driver_init(&intel_idle_driver);
2663 	cmdline_table_adjust(&intel_idle_driver);
2664 
2665 	retval = intel_idle_sysfs_init();
2666 	if (retval)
2667 		pr_warn("failed to initialized sysfs");
2668 
2669 	retval = cpuidle_register_driver(&intel_idle_driver);
2670 	if (retval) {
2671 		struct cpuidle_driver *drv = cpuidle_get_driver();
2672 		printk(KERN_DEBUG pr_fmt("intel_idle yielding to %s\n"),
2673 		       drv ? drv->name : "none");
2674 		goto init_driver_fail;
2675 	}
2676 
2677 	retval = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "idle/intel:online",
2678 				   intel_idle_cpu_online, NULL);
2679 	if (retval < 0)
2680 		goto hp_setup_fail;
2681 
2682 	pr_debug("Local APIC timer is reliable in %s\n",
2683 		 boot_cpu_has(X86_FEATURE_ARAT) ? "all C-states" : "C1");
2684 
2685 	arch_cpu_rescan_dead_smt_siblings();
2686 
2687 	return 0;
2688 
2689 hp_setup_fail:
2690 	intel_idle_cpuidle_devices_uninit();
2691 	cpuidle_unregister_driver(&intel_idle_driver);
2692 init_driver_fail:
2693 	intel_idle_sysfs_uninit();
2694 	free_percpu(intel_idle_cpuidle_devices);
2695 	return retval;
2696 
2697 }
2698 subsys_initcall_sync(intel_idle_init);
2699 
2700 /*
2701  * We are not really modular, but we used to support that.  Meaning we also
2702  * support "intel_idle.max_cstate=..." at boot and also a read-only export of
2703  * it at /sys/module/intel_idle/parameters/max_cstate -- so using module_param
2704  * is the easiest way (currently) to continue doing that.
2705  */
2706 module_param(max_cstate, int, 0444);
2707 /*
2708  * The positions of the bits that are set in this number are the indices of the
2709  * idle states to be disabled by default (as reflected by the names of the
2710  * corresponding idle state directories in sysfs, "state0", "state1" ...
2711  * "state<i>" ..., where <i> is the index of the given state).
2712  */
2713 module_param_named(states_off, disabled_states_mask, uint, 0444);
2714 MODULE_PARM_DESC(states_off, "Mask of disabled idle states");
2715 /*
2716  * Debugging option that forces the driver to enter all C-states with
2717  * interrupts enabled. Does not apply to C-states with
2718  * 'CPUIDLE_FLAG_INIT_XSTATE' and 'CPUIDLE_FLAG_IBRS' flags.
2719  */
2720 module_param(force_irq_on, bool, 0444);
2721 /*
2722  * Force the disabling of IBRS when X86_FEATURE_KERNEL_IBRS is on and
2723  * CPUIDLE_FLAG_IRQ_ENABLE isn't set.
2724  */
2725 module_param(ibrs_off, bool, 0444);
2726 MODULE_PARM_DESC(ibrs_off, "Disable IBRS when idle");
2727 
2728 /*
2729  * Define the C-states table from a user input string. Expected format is
2730  * 'name:latency:residency', where:
2731  * - name: The C-state name.
2732  * - latency: The C-state exit latency in us.
2733  * - residency: The C-state target residency in us.
2734  *
2735  * Multiple C-states can be defined by separating them with commas:
2736  * 'name1:latency1:residency1,name2:latency2:residency2'
2737  *
2738  * Example: intel_idle.table=C1:1:1,C1E:5:10,C6:100:600
2739  *
2740  * To leave latency or residency unchanged, use an empty field, for example:
2741  * 'C1:1:1,C1E::10' - leaves C1E latency unchanged.
2742  */
2743 module_param_string(table, cmdline_table_str, MAX_CMDLINE_TABLE_LEN, 0444);
2744 MODULE_PARM_DESC(table, "Build the C-states table from a user input string");
2745