xref: /linux/drivers/idle/intel_idle.c (revision c5951e7c8ee5cb04b8b41c32bf567b90117a2124)
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, Intel Corporation.
6  * Len Brown <len.brown@intel.com>
7  */
8 
9 /*
10  * intel_idle is a cpuidle driver that loads on specific Intel processors
11  * in lieu of the legacy ACPI processor_idle driver.  The intent is to
12  * make Linux more efficient on these processors, as intel_idle knows
13  * more than ACPI, as well as make Linux more immune to ACPI BIOS bugs.
14  */
15 
16 /*
17  * Design Assumptions
18  *
19  * All CPUs have same idle states as boot CPU
20  *
21  * Chipset BM_STS (bus master status) bit is a NOP
22  *	for preventing entry into deep C-stats
23  */
24 
25 /*
26  * Known limitations
27  *
28  * The driver currently initializes for_each_online_cpu() upon modprobe.
29  * It it unaware of subsequent processors hot-added to the system.
30  * This means that if you boot with maxcpus=n and later online
31  * processors above n, those processors will use C1 only.
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 <trace/events/power.h>
49 #include <linux/sched.h>
50 #include <linux/notifier.h>
51 #include <linux/cpu.h>
52 #include <linux/moduleparam.h>
53 #include <asm/cpu_device_id.h>
54 #include <asm/intel-family.h>
55 #include <asm/mwait.h>
56 #include <asm/msr.h>
57 
58 #define INTEL_IDLE_VERSION "0.4.1"
59 
60 static struct cpuidle_driver intel_idle_driver = {
61 	.name = "intel_idle",
62 	.owner = THIS_MODULE,
63 };
64 /* intel_idle.max_cstate=0 disables driver */
65 static int max_cstate = CPUIDLE_STATE_MAX - 1;
66 
67 static unsigned int mwait_substates;
68 
69 #define LAPIC_TIMER_ALWAYS_RELIABLE 0xFFFFFFFF
70 /* Reliable LAPIC Timer States, bit 1 for C1 etc.  */
71 static unsigned int lapic_timer_reliable_states = (1 << 1);	 /* Default to only C1 */
72 
73 struct idle_cpu {
74 	struct cpuidle_state *state_table;
75 
76 	/*
77 	 * Hardware C-state auto-demotion may not always be optimal.
78 	 * Indicate which enable bits to clear here.
79 	 */
80 	unsigned long auto_demotion_disable_flags;
81 	bool byt_auto_demotion_disable_flag;
82 	bool disable_promotion_to_c1e;
83 	bool use_acpi;
84 };
85 
86 static const struct idle_cpu *icpu;
87 static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
88 static int intel_idle(struct cpuidle_device *dev,
89 			struct cpuidle_driver *drv, int index);
90 static void intel_idle_s2idle(struct cpuidle_device *dev,
91 			      struct cpuidle_driver *drv, int index);
92 static struct cpuidle_state *cpuidle_state_table;
93 
94 /*
95  * Enable this state by default even if the ACPI _CST does not list it.
96  */
97 #define CPUIDLE_FLAG_ALWAYS_ENABLE	BIT(15)
98 
99 /*
100  * Set this flag for states where the HW flushes the TLB for us
101  * and so we don't need cross-calls to keep it consistent.
102  * If this flag is set, SW flushes the TLB, so even if the
103  * HW doesn't do the flushing, this flag is safe to use.
104  */
105 #define CPUIDLE_FLAG_TLB_FLUSHED	0x10000
106 
107 /*
108  * MWAIT takes an 8-bit "hint" in EAX "suggesting"
109  * the C-state (top nibble) and sub-state (bottom nibble)
110  * 0x00 means "MWAIT(C1)", 0x10 means "MWAIT(C2)" etc.
111  *
112  * We store the hint at the top of our "flags" for each state.
113  */
114 #define flg2MWAIT(flags) (((flags) >> 24) & 0xFF)
115 #define MWAIT2flg(eax) ((eax & 0xFF) << 24)
116 
117 /*
118  * States are indexed by the cstate number,
119  * which is also the index into the MWAIT hint array.
120  * Thus C0 is a dummy.
121  */
122 static struct cpuidle_state nehalem_cstates[] = {
123 	{
124 		.name = "C1",
125 		.desc = "MWAIT 0x00",
126 		.flags = MWAIT2flg(0x00),
127 		.exit_latency = 3,
128 		.target_residency = 6,
129 		.enter = &intel_idle,
130 		.enter_s2idle = intel_idle_s2idle, },
131 	{
132 		.name = "C1E",
133 		.desc = "MWAIT 0x01",
134 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
135 		.exit_latency = 10,
136 		.target_residency = 20,
137 		.enter = &intel_idle,
138 		.enter_s2idle = intel_idle_s2idle, },
139 	{
140 		.name = "C3",
141 		.desc = "MWAIT 0x10",
142 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
143 		.exit_latency = 20,
144 		.target_residency = 80,
145 		.enter = &intel_idle,
146 		.enter_s2idle = intel_idle_s2idle, },
147 	{
148 		.name = "C6",
149 		.desc = "MWAIT 0x20",
150 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
151 		.exit_latency = 200,
152 		.target_residency = 800,
153 		.enter = &intel_idle,
154 		.enter_s2idle = intel_idle_s2idle, },
155 	{
156 		.enter = NULL }
157 };
158 
159 static struct cpuidle_state snb_cstates[] = {
160 	{
161 		.name = "C1",
162 		.desc = "MWAIT 0x00",
163 		.flags = MWAIT2flg(0x00),
164 		.exit_latency = 2,
165 		.target_residency = 2,
166 		.enter = &intel_idle,
167 		.enter_s2idle = intel_idle_s2idle, },
168 	{
169 		.name = "C1E",
170 		.desc = "MWAIT 0x01",
171 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
172 		.exit_latency = 10,
173 		.target_residency = 20,
174 		.enter = &intel_idle,
175 		.enter_s2idle = intel_idle_s2idle, },
176 	{
177 		.name = "C3",
178 		.desc = "MWAIT 0x10",
179 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
180 		.exit_latency = 80,
181 		.target_residency = 211,
182 		.enter = &intel_idle,
183 		.enter_s2idle = intel_idle_s2idle, },
184 	{
185 		.name = "C6",
186 		.desc = "MWAIT 0x20",
187 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
188 		.exit_latency = 104,
189 		.target_residency = 345,
190 		.enter = &intel_idle,
191 		.enter_s2idle = intel_idle_s2idle, },
192 	{
193 		.name = "C7",
194 		.desc = "MWAIT 0x30",
195 		.flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
196 		.exit_latency = 109,
197 		.target_residency = 345,
198 		.enter = &intel_idle,
199 		.enter_s2idle = intel_idle_s2idle, },
200 	{
201 		.enter = NULL }
202 };
203 
204 static struct cpuidle_state byt_cstates[] = {
205 	{
206 		.name = "C1",
207 		.desc = "MWAIT 0x00",
208 		.flags = MWAIT2flg(0x00),
209 		.exit_latency = 1,
210 		.target_residency = 1,
211 		.enter = &intel_idle,
212 		.enter_s2idle = intel_idle_s2idle, },
213 	{
214 		.name = "C6N",
215 		.desc = "MWAIT 0x58",
216 		.flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
217 		.exit_latency = 300,
218 		.target_residency = 275,
219 		.enter = &intel_idle,
220 		.enter_s2idle = intel_idle_s2idle, },
221 	{
222 		.name = "C6S",
223 		.desc = "MWAIT 0x52",
224 		.flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
225 		.exit_latency = 500,
226 		.target_residency = 560,
227 		.enter = &intel_idle,
228 		.enter_s2idle = intel_idle_s2idle, },
229 	{
230 		.name = "C7",
231 		.desc = "MWAIT 0x60",
232 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
233 		.exit_latency = 1200,
234 		.target_residency = 4000,
235 		.enter = &intel_idle,
236 		.enter_s2idle = intel_idle_s2idle, },
237 	{
238 		.name = "C7S",
239 		.desc = "MWAIT 0x64",
240 		.flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
241 		.exit_latency = 10000,
242 		.target_residency = 20000,
243 		.enter = &intel_idle,
244 		.enter_s2idle = intel_idle_s2idle, },
245 	{
246 		.enter = NULL }
247 };
248 
249 static struct cpuidle_state cht_cstates[] = {
250 	{
251 		.name = "C1",
252 		.desc = "MWAIT 0x00",
253 		.flags = MWAIT2flg(0x00),
254 		.exit_latency = 1,
255 		.target_residency = 1,
256 		.enter = &intel_idle,
257 		.enter_s2idle = intel_idle_s2idle, },
258 	{
259 		.name = "C6N",
260 		.desc = "MWAIT 0x58",
261 		.flags = MWAIT2flg(0x58) | CPUIDLE_FLAG_TLB_FLUSHED,
262 		.exit_latency = 80,
263 		.target_residency = 275,
264 		.enter = &intel_idle,
265 		.enter_s2idle = intel_idle_s2idle, },
266 	{
267 		.name = "C6S",
268 		.desc = "MWAIT 0x52",
269 		.flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
270 		.exit_latency = 200,
271 		.target_residency = 560,
272 		.enter = &intel_idle,
273 		.enter_s2idle = intel_idle_s2idle, },
274 	{
275 		.name = "C7",
276 		.desc = "MWAIT 0x60",
277 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
278 		.exit_latency = 1200,
279 		.target_residency = 4000,
280 		.enter = &intel_idle,
281 		.enter_s2idle = intel_idle_s2idle, },
282 	{
283 		.name = "C7S",
284 		.desc = "MWAIT 0x64",
285 		.flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
286 		.exit_latency = 10000,
287 		.target_residency = 20000,
288 		.enter = &intel_idle,
289 		.enter_s2idle = intel_idle_s2idle, },
290 	{
291 		.enter = NULL }
292 };
293 
294 static struct cpuidle_state ivb_cstates[] = {
295 	{
296 		.name = "C1",
297 		.desc = "MWAIT 0x00",
298 		.flags = MWAIT2flg(0x00),
299 		.exit_latency = 1,
300 		.target_residency = 1,
301 		.enter = &intel_idle,
302 		.enter_s2idle = intel_idle_s2idle, },
303 	{
304 		.name = "C1E",
305 		.desc = "MWAIT 0x01",
306 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
307 		.exit_latency = 10,
308 		.target_residency = 20,
309 		.enter = &intel_idle,
310 		.enter_s2idle = intel_idle_s2idle, },
311 	{
312 		.name = "C3",
313 		.desc = "MWAIT 0x10",
314 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
315 		.exit_latency = 59,
316 		.target_residency = 156,
317 		.enter = &intel_idle,
318 		.enter_s2idle = intel_idle_s2idle, },
319 	{
320 		.name = "C6",
321 		.desc = "MWAIT 0x20",
322 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
323 		.exit_latency = 80,
324 		.target_residency = 300,
325 		.enter = &intel_idle,
326 		.enter_s2idle = intel_idle_s2idle, },
327 	{
328 		.name = "C7",
329 		.desc = "MWAIT 0x30",
330 		.flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
331 		.exit_latency = 87,
332 		.target_residency = 300,
333 		.enter = &intel_idle,
334 		.enter_s2idle = intel_idle_s2idle, },
335 	{
336 		.enter = NULL }
337 };
338 
339 static struct cpuidle_state ivt_cstates[] = {
340 	{
341 		.name = "C1",
342 		.desc = "MWAIT 0x00",
343 		.flags = MWAIT2flg(0x00),
344 		.exit_latency = 1,
345 		.target_residency = 1,
346 		.enter = &intel_idle,
347 		.enter_s2idle = intel_idle_s2idle, },
348 	{
349 		.name = "C1E",
350 		.desc = "MWAIT 0x01",
351 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
352 		.exit_latency = 10,
353 		.target_residency = 80,
354 		.enter = &intel_idle,
355 		.enter_s2idle = intel_idle_s2idle, },
356 	{
357 		.name = "C3",
358 		.desc = "MWAIT 0x10",
359 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
360 		.exit_latency = 59,
361 		.target_residency = 156,
362 		.enter = &intel_idle,
363 		.enter_s2idle = intel_idle_s2idle, },
364 	{
365 		.name = "C6",
366 		.desc = "MWAIT 0x20",
367 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
368 		.exit_latency = 82,
369 		.target_residency = 300,
370 		.enter = &intel_idle,
371 		.enter_s2idle = intel_idle_s2idle, },
372 	{
373 		.enter = NULL }
374 };
375 
376 static struct cpuidle_state ivt_cstates_4s[] = {
377 	{
378 		.name = "C1",
379 		.desc = "MWAIT 0x00",
380 		.flags = MWAIT2flg(0x00),
381 		.exit_latency = 1,
382 		.target_residency = 1,
383 		.enter = &intel_idle,
384 		.enter_s2idle = intel_idle_s2idle, },
385 	{
386 		.name = "C1E",
387 		.desc = "MWAIT 0x01",
388 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
389 		.exit_latency = 10,
390 		.target_residency = 250,
391 		.enter = &intel_idle,
392 		.enter_s2idle = intel_idle_s2idle, },
393 	{
394 		.name = "C3",
395 		.desc = "MWAIT 0x10",
396 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
397 		.exit_latency = 59,
398 		.target_residency = 300,
399 		.enter = &intel_idle,
400 		.enter_s2idle = intel_idle_s2idle, },
401 	{
402 		.name = "C6",
403 		.desc = "MWAIT 0x20",
404 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
405 		.exit_latency = 84,
406 		.target_residency = 400,
407 		.enter = &intel_idle,
408 		.enter_s2idle = intel_idle_s2idle, },
409 	{
410 		.enter = NULL }
411 };
412 
413 static struct cpuidle_state ivt_cstates_8s[] = {
414 	{
415 		.name = "C1",
416 		.desc = "MWAIT 0x00",
417 		.flags = MWAIT2flg(0x00),
418 		.exit_latency = 1,
419 		.target_residency = 1,
420 		.enter = &intel_idle,
421 		.enter_s2idle = intel_idle_s2idle, },
422 	{
423 		.name = "C1E",
424 		.desc = "MWAIT 0x01",
425 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
426 		.exit_latency = 10,
427 		.target_residency = 500,
428 		.enter = &intel_idle,
429 		.enter_s2idle = intel_idle_s2idle, },
430 	{
431 		.name = "C3",
432 		.desc = "MWAIT 0x10",
433 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
434 		.exit_latency = 59,
435 		.target_residency = 600,
436 		.enter = &intel_idle,
437 		.enter_s2idle = intel_idle_s2idle, },
438 	{
439 		.name = "C6",
440 		.desc = "MWAIT 0x20",
441 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
442 		.exit_latency = 88,
443 		.target_residency = 700,
444 		.enter = &intel_idle,
445 		.enter_s2idle = intel_idle_s2idle, },
446 	{
447 		.enter = NULL }
448 };
449 
450 static struct cpuidle_state hsw_cstates[] = {
451 	{
452 		.name = "C1",
453 		.desc = "MWAIT 0x00",
454 		.flags = MWAIT2flg(0x00),
455 		.exit_latency = 2,
456 		.target_residency = 2,
457 		.enter = &intel_idle,
458 		.enter_s2idle = intel_idle_s2idle, },
459 	{
460 		.name = "C1E",
461 		.desc = "MWAIT 0x01",
462 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
463 		.exit_latency = 10,
464 		.target_residency = 20,
465 		.enter = &intel_idle,
466 		.enter_s2idle = intel_idle_s2idle, },
467 	{
468 		.name = "C3",
469 		.desc = "MWAIT 0x10",
470 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
471 		.exit_latency = 33,
472 		.target_residency = 100,
473 		.enter = &intel_idle,
474 		.enter_s2idle = intel_idle_s2idle, },
475 	{
476 		.name = "C6",
477 		.desc = "MWAIT 0x20",
478 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
479 		.exit_latency = 133,
480 		.target_residency = 400,
481 		.enter = &intel_idle,
482 		.enter_s2idle = intel_idle_s2idle, },
483 	{
484 		.name = "C7s",
485 		.desc = "MWAIT 0x32",
486 		.flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
487 		.exit_latency = 166,
488 		.target_residency = 500,
489 		.enter = &intel_idle,
490 		.enter_s2idle = intel_idle_s2idle, },
491 	{
492 		.name = "C8",
493 		.desc = "MWAIT 0x40",
494 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
495 		.exit_latency = 300,
496 		.target_residency = 900,
497 		.enter = &intel_idle,
498 		.enter_s2idle = intel_idle_s2idle, },
499 	{
500 		.name = "C9",
501 		.desc = "MWAIT 0x50",
502 		.flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
503 		.exit_latency = 600,
504 		.target_residency = 1800,
505 		.enter = &intel_idle,
506 		.enter_s2idle = intel_idle_s2idle, },
507 	{
508 		.name = "C10",
509 		.desc = "MWAIT 0x60",
510 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
511 		.exit_latency = 2600,
512 		.target_residency = 7700,
513 		.enter = &intel_idle,
514 		.enter_s2idle = intel_idle_s2idle, },
515 	{
516 		.enter = NULL }
517 };
518 static struct cpuidle_state bdw_cstates[] = {
519 	{
520 		.name = "C1",
521 		.desc = "MWAIT 0x00",
522 		.flags = MWAIT2flg(0x00),
523 		.exit_latency = 2,
524 		.target_residency = 2,
525 		.enter = &intel_idle,
526 		.enter_s2idle = intel_idle_s2idle, },
527 	{
528 		.name = "C1E",
529 		.desc = "MWAIT 0x01",
530 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
531 		.exit_latency = 10,
532 		.target_residency = 20,
533 		.enter = &intel_idle,
534 		.enter_s2idle = intel_idle_s2idle, },
535 	{
536 		.name = "C3",
537 		.desc = "MWAIT 0x10",
538 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
539 		.exit_latency = 40,
540 		.target_residency = 100,
541 		.enter = &intel_idle,
542 		.enter_s2idle = intel_idle_s2idle, },
543 	{
544 		.name = "C6",
545 		.desc = "MWAIT 0x20",
546 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
547 		.exit_latency = 133,
548 		.target_residency = 400,
549 		.enter = &intel_idle,
550 		.enter_s2idle = intel_idle_s2idle, },
551 	{
552 		.name = "C7s",
553 		.desc = "MWAIT 0x32",
554 		.flags = MWAIT2flg(0x32) | CPUIDLE_FLAG_TLB_FLUSHED,
555 		.exit_latency = 166,
556 		.target_residency = 500,
557 		.enter = &intel_idle,
558 		.enter_s2idle = intel_idle_s2idle, },
559 	{
560 		.name = "C8",
561 		.desc = "MWAIT 0x40",
562 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
563 		.exit_latency = 300,
564 		.target_residency = 900,
565 		.enter = &intel_idle,
566 		.enter_s2idle = intel_idle_s2idle, },
567 	{
568 		.name = "C9",
569 		.desc = "MWAIT 0x50",
570 		.flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
571 		.exit_latency = 600,
572 		.target_residency = 1800,
573 		.enter = &intel_idle,
574 		.enter_s2idle = intel_idle_s2idle, },
575 	{
576 		.name = "C10",
577 		.desc = "MWAIT 0x60",
578 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
579 		.exit_latency = 2600,
580 		.target_residency = 7700,
581 		.enter = &intel_idle,
582 		.enter_s2idle = intel_idle_s2idle, },
583 	{
584 		.enter = NULL }
585 };
586 
587 static struct cpuidle_state skl_cstates[] = {
588 	{
589 		.name = "C1",
590 		.desc = "MWAIT 0x00",
591 		.flags = MWAIT2flg(0x00),
592 		.exit_latency = 2,
593 		.target_residency = 2,
594 		.enter = &intel_idle,
595 		.enter_s2idle = intel_idle_s2idle, },
596 	{
597 		.name = "C1E",
598 		.desc = "MWAIT 0x01",
599 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
600 		.exit_latency = 10,
601 		.target_residency = 20,
602 		.enter = &intel_idle,
603 		.enter_s2idle = intel_idle_s2idle, },
604 	{
605 		.name = "C3",
606 		.desc = "MWAIT 0x10",
607 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
608 		.exit_latency = 70,
609 		.target_residency = 100,
610 		.enter = &intel_idle,
611 		.enter_s2idle = intel_idle_s2idle, },
612 	{
613 		.name = "C6",
614 		.desc = "MWAIT 0x20",
615 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
616 		.exit_latency = 85,
617 		.target_residency = 200,
618 		.enter = &intel_idle,
619 		.enter_s2idle = intel_idle_s2idle, },
620 	{
621 		.name = "C7s",
622 		.desc = "MWAIT 0x33",
623 		.flags = MWAIT2flg(0x33) | CPUIDLE_FLAG_TLB_FLUSHED,
624 		.exit_latency = 124,
625 		.target_residency = 800,
626 		.enter = &intel_idle,
627 		.enter_s2idle = intel_idle_s2idle, },
628 	{
629 		.name = "C8",
630 		.desc = "MWAIT 0x40",
631 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
632 		.exit_latency = 200,
633 		.target_residency = 800,
634 		.enter = &intel_idle,
635 		.enter_s2idle = intel_idle_s2idle, },
636 	{
637 		.name = "C9",
638 		.desc = "MWAIT 0x50",
639 		.flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
640 		.exit_latency = 480,
641 		.target_residency = 5000,
642 		.enter = &intel_idle,
643 		.enter_s2idle = intel_idle_s2idle, },
644 	{
645 		.name = "C10",
646 		.desc = "MWAIT 0x60",
647 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
648 		.exit_latency = 890,
649 		.target_residency = 5000,
650 		.enter = &intel_idle,
651 		.enter_s2idle = intel_idle_s2idle, },
652 	{
653 		.enter = NULL }
654 };
655 
656 static struct cpuidle_state skx_cstates[] = {
657 	{
658 		.name = "C1",
659 		.desc = "MWAIT 0x00",
660 		.flags = MWAIT2flg(0x00),
661 		.exit_latency = 2,
662 		.target_residency = 2,
663 		.enter = &intel_idle,
664 		.enter_s2idle = intel_idle_s2idle, },
665 	{
666 		.name = "C1E",
667 		.desc = "MWAIT 0x01",
668 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
669 		.exit_latency = 10,
670 		.target_residency = 20,
671 		.enter = &intel_idle,
672 		.enter_s2idle = intel_idle_s2idle, },
673 	{
674 		.name = "C6",
675 		.desc = "MWAIT 0x20",
676 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
677 		.exit_latency = 133,
678 		.target_residency = 600,
679 		.enter = &intel_idle,
680 		.enter_s2idle = intel_idle_s2idle, },
681 	{
682 		.enter = NULL }
683 };
684 
685 static struct cpuidle_state atom_cstates[] = {
686 	{
687 		.name = "C1E",
688 		.desc = "MWAIT 0x00",
689 		.flags = MWAIT2flg(0x00),
690 		.exit_latency = 10,
691 		.target_residency = 20,
692 		.enter = &intel_idle,
693 		.enter_s2idle = intel_idle_s2idle, },
694 	{
695 		.name = "C2",
696 		.desc = "MWAIT 0x10",
697 		.flags = MWAIT2flg(0x10),
698 		.exit_latency = 20,
699 		.target_residency = 80,
700 		.enter = &intel_idle,
701 		.enter_s2idle = intel_idle_s2idle, },
702 	{
703 		.name = "C4",
704 		.desc = "MWAIT 0x30",
705 		.flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
706 		.exit_latency = 100,
707 		.target_residency = 400,
708 		.enter = &intel_idle,
709 		.enter_s2idle = intel_idle_s2idle, },
710 	{
711 		.name = "C6",
712 		.desc = "MWAIT 0x52",
713 		.flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
714 		.exit_latency = 140,
715 		.target_residency = 560,
716 		.enter = &intel_idle,
717 		.enter_s2idle = intel_idle_s2idle, },
718 	{
719 		.enter = NULL }
720 };
721 static struct cpuidle_state tangier_cstates[] = {
722 	{
723 		.name = "C1",
724 		.desc = "MWAIT 0x00",
725 		.flags = MWAIT2flg(0x00),
726 		.exit_latency = 1,
727 		.target_residency = 4,
728 		.enter = &intel_idle,
729 		.enter_s2idle = intel_idle_s2idle, },
730 	{
731 		.name = "C4",
732 		.desc = "MWAIT 0x30",
733 		.flags = MWAIT2flg(0x30) | CPUIDLE_FLAG_TLB_FLUSHED,
734 		.exit_latency = 100,
735 		.target_residency = 400,
736 		.enter = &intel_idle,
737 		.enter_s2idle = intel_idle_s2idle, },
738 	{
739 		.name = "C6",
740 		.desc = "MWAIT 0x52",
741 		.flags = MWAIT2flg(0x52) | CPUIDLE_FLAG_TLB_FLUSHED,
742 		.exit_latency = 140,
743 		.target_residency = 560,
744 		.enter = &intel_idle,
745 		.enter_s2idle = intel_idle_s2idle, },
746 	{
747 		.name = "C7",
748 		.desc = "MWAIT 0x60",
749 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
750 		.exit_latency = 1200,
751 		.target_residency = 4000,
752 		.enter = &intel_idle,
753 		.enter_s2idle = intel_idle_s2idle, },
754 	{
755 		.name = "C9",
756 		.desc = "MWAIT 0x64",
757 		.flags = MWAIT2flg(0x64) | CPUIDLE_FLAG_TLB_FLUSHED,
758 		.exit_latency = 10000,
759 		.target_residency = 20000,
760 		.enter = &intel_idle,
761 		.enter_s2idle = intel_idle_s2idle, },
762 	{
763 		.enter = NULL }
764 };
765 static struct cpuidle_state avn_cstates[] = {
766 	{
767 		.name = "C1",
768 		.desc = "MWAIT 0x00",
769 		.flags = MWAIT2flg(0x00),
770 		.exit_latency = 2,
771 		.target_residency = 2,
772 		.enter = &intel_idle,
773 		.enter_s2idle = intel_idle_s2idle, },
774 	{
775 		.name = "C6",
776 		.desc = "MWAIT 0x51",
777 		.flags = MWAIT2flg(0x51) | CPUIDLE_FLAG_TLB_FLUSHED,
778 		.exit_latency = 15,
779 		.target_residency = 45,
780 		.enter = &intel_idle,
781 		.enter_s2idle = intel_idle_s2idle, },
782 	{
783 		.enter = NULL }
784 };
785 static struct cpuidle_state knl_cstates[] = {
786 	{
787 		.name = "C1",
788 		.desc = "MWAIT 0x00",
789 		.flags = MWAIT2flg(0x00),
790 		.exit_latency = 1,
791 		.target_residency = 2,
792 		.enter = &intel_idle,
793 		.enter_s2idle = intel_idle_s2idle },
794 	{
795 		.name = "C6",
796 		.desc = "MWAIT 0x10",
797 		.flags = MWAIT2flg(0x10) | CPUIDLE_FLAG_TLB_FLUSHED,
798 		.exit_latency = 120,
799 		.target_residency = 500,
800 		.enter = &intel_idle,
801 		.enter_s2idle = intel_idle_s2idle },
802 	{
803 		.enter = NULL }
804 };
805 
806 static struct cpuidle_state bxt_cstates[] = {
807 	{
808 		.name = "C1",
809 		.desc = "MWAIT 0x00",
810 		.flags = MWAIT2flg(0x00),
811 		.exit_latency = 2,
812 		.target_residency = 2,
813 		.enter = &intel_idle,
814 		.enter_s2idle = intel_idle_s2idle, },
815 	{
816 		.name = "C1E",
817 		.desc = "MWAIT 0x01",
818 		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
819 		.exit_latency = 10,
820 		.target_residency = 20,
821 		.enter = &intel_idle,
822 		.enter_s2idle = intel_idle_s2idle, },
823 	{
824 		.name = "C6",
825 		.desc = "MWAIT 0x20",
826 		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
827 		.exit_latency = 133,
828 		.target_residency = 133,
829 		.enter = &intel_idle,
830 		.enter_s2idle = intel_idle_s2idle, },
831 	{
832 		.name = "C7s",
833 		.desc = "MWAIT 0x31",
834 		.flags = MWAIT2flg(0x31) | CPUIDLE_FLAG_TLB_FLUSHED,
835 		.exit_latency = 155,
836 		.target_residency = 155,
837 		.enter = &intel_idle,
838 		.enter_s2idle = intel_idle_s2idle, },
839 	{
840 		.name = "C8",
841 		.desc = "MWAIT 0x40",
842 		.flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED,
843 		.exit_latency = 1000,
844 		.target_residency = 1000,
845 		.enter = &intel_idle,
846 		.enter_s2idle = intel_idle_s2idle, },
847 	{
848 		.name = "C9",
849 		.desc = "MWAIT 0x50",
850 		.flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED,
851 		.exit_latency = 2000,
852 		.target_residency = 2000,
853 		.enter = &intel_idle,
854 		.enter_s2idle = intel_idle_s2idle, },
855 	{
856 		.name = "C10",
857 		.desc = "MWAIT 0x60",
858 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
859 		.exit_latency = 10000,
860 		.target_residency = 10000,
861 		.enter = &intel_idle,
862 		.enter_s2idle = intel_idle_s2idle, },
863 	{
864 		.enter = NULL }
865 };
866 
867 static struct cpuidle_state dnv_cstates[] = {
868 	{
869 		.name = "C1",
870 		.desc = "MWAIT 0x00",
871 		.flags = MWAIT2flg(0x00),
872 		.exit_latency = 2,
873 		.target_residency = 2,
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 = 10,
881 		.target_residency = 20,
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 = 50,
889 		.target_residency = 500,
890 		.enter = &intel_idle,
891 		.enter_s2idle = intel_idle_s2idle, },
892 	{
893 		.enter = NULL }
894 };
895 
896 /**
897  * intel_idle
898  * @dev: cpuidle_device
899  * @drv: cpuidle driver
900  * @index: index of cpuidle state
901  *
902  * Must be called under local_irq_disable().
903  */
904 static __cpuidle int intel_idle(struct cpuidle_device *dev,
905 				struct cpuidle_driver *drv, int index)
906 {
907 	unsigned long ecx = 1; /* break on interrupt flag */
908 	struct cpuidle_state *state = &drv->states[index];
909 	unsigned long eax = flg2MWAIT(state->flags);
910 	unsigned int cstate;
911 	bool uninitialized_var(tick);
912 	int cpu = smp_processor_id();
913 
914 	/*
915 	 * leave_mm() to avoid costly and often unnecessary wakeups
916 	 * for flushing the user TLB's associated with the active mm.
917 	 */
918 	if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED)
919 		leave_mm(cpu);
920 
921 	if (!static_cpu_has(X86_FEATURE_ARAT)) {
922 		cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) &
923 				MWAIT_CSTATE_MASK) + 1;
924 		tick = false;
925 		if (!(lapic_timer_reliable_states & (1 << (cstate)))) {
926 			tick = true;
927 			tick_broadcast_enter();
928 		}
929 	}
930 
931 	mwait_idle_with_hints(eax, ecx);
932 
933 	if (!static_cpu_has(X86_FEATURE_ARAT) && tick)
934 		tick_broadcast_exit();
935 
936 	return index;
937 }
938 
939 /**
940  * intel_idle_s2idle - simplified "enter" callback routine for suspend-to-idle
941  * @dev: cpuidle_device
942  * @drv: cpuidle driver
943  * @index: state index
944  */
945 static void intel_idle_s2idle(struct cpuidle_device *dev,
946 			     struct cpuidle_driver *drv, int index)
947 {
948 	unsigned long ecx = 1; /* break on interrupt flag */
949 	unsigned long eax = flg2MWAIT(drv->states[index].flags);
950 
951 	mwait_idle_with_hints(eax, ecx);
952 }
953 
954 static const struct idle_cpu idle_cpu_nehalem = {
955 	.state_table = nehalem_cstates,
956 	.auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
957 	.disable_promotion_to_c1e = true,
958 };
959 
960 static const struct idle_cpu idle_cpu_nhx = {
961 	.state_table = nehalem_cstates,
962 	.auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
963 	.disable_promotion_to_c1e = true,
964 	.use_acpi = true,
965 };
966 
967 static const struct idle_cpu idle_cpu_atom = {
968 	.state_table = atom_cstates,
969 };
970 
971 static const struct idle_cpu idle_cpu_tangier = {
972 	.state_table = tangier_cstates,
973 };
974 
975 static const struct idle_cpu idle_cpu_lincroft = {
976 	.state_table = atom_cstates,
977 	.auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE,
978 };
979 
980 static const struct idle_cpu idle_cpu_snb = {
981 	.state_table = snb_cstates,
982 	.disable_promotion_to_c1e = true,
983 };
984 
985 static const struct idle_cpu idle_cpu_snx = {
986 	.state_table = snb_cstates,
987 	.disable_promotion_to_c1e = true,
988 	.use_acpi = true,
989 };
990 
991 static const struct idle_cpu idle_cpu_byt = {
992 	.state_table = byt_cstates,
993 	.disable_promotion_to_c1e = true,
994 	.byt_auto_demotion_disable_flag = true,
995 };
996 
997 static const struct idle_cpu idle_cpu_cht = {
998 	.state_table = cht_cstates,
999 	.disable_promotion_to_c1e = true,
1000 	.byt_auto_demotion_disable_flag = true,
1001 };
1002 
1003 static const struct idle_cpu idle_cpu_ivb = {
1004 	.state_table = ivb_cstates,
1005 	.disable_promotion_to_c1e = true,
1006 };
1007 
1008 static const struct idle_cpu idle_cpu_ivt = {
1009 	.state_table = ivt_cstates,
1010 	.disable_promotion_to_c1e = true,
1011 	.use_acpi = true,
1012 };
1013 
1014 static const struct idle_cpu idle_cpu_hsw = {
1015 	.state_table = hsw_cstates,
1016 	.disable_promotion_to_c1e = true,
1017 };
1018 
1019 static const struct idle_cpu idle_cpu_hsx = {
1020 	.state_table = hsw_cstates,
1021 	.disable_promotion_to_c1e = true,
1022 	.use_acpi = true,
1023 };
1024 
1025 static const struct idle_cpu idle_cpu_bdw = {
1026 	.state_table = bdw_cstates,
1027 	.disable_promotion_to_c1e = true,
1028 };
1029 
1030 static const struct idle_cpu idle_cpu_bdx = {
1031 	.state_table = bdw_cstates,
1032 	.disable_promotion_to_c1e = true,
1033 	.use_acpi = true,
1034 };
1035 
1036 static const struct idle_cpu idle_cpu_skl = {
1037 	.state_table = skl_cstates,
1038 	.disable_promotion_to_c1e = true,
1039 };
1040 
1041 static const struct idle_cpu idle_cpu_skx = {
1042 	.state_table = skx_cstates,
1043 	.disable_promotion_to_c1e = true,
1044 	.use_acpi = true,
1045 };
1046 
1047 static const struct idle_cpu idle_cpu_avn = {
1048 	.state_table = avn_cstates,
1049 	.disable_promotion_to_c1e = true,
1050 	.use_acpi = true,
1051 };
1052 
1053 static const struct idle_cpu idle_cpu_knl = {
1054 	.state_table = knl_cstates,
1055 	.use_acpi = true,
1056 };
1057 
1058 static const struct idle_cpu idle_cpu_bxt = {
1059 	.state_table = bxt_cstates,
1060 	.disable_promotion_to_c1e = true,
1061 };
1062 
1063 static const struct idle_cpu idle_cpu_dnv = {
1064 	.state_table = dnv_cstates,
1065 	.disable_promotion_to_c1e = true,
1066 	.use_acpi = true,
1067 };
1068 
1069 static const struct x86_cpu_id intel_idle_ids[] __initconst = {
1070 	INTEL_CPU_FAM6(NEHALEM_EP,		idle_cpu_nhx),
1071 	INTEL_CPU_FAM6(NEHALEM,			idle_cpu_nehalem),
1072 	INTEL_CPU_FAM6(NEHALEM_G,		idle_cpu_nehalem),
1073 	INTEL_CPU_FAM6(WESTMERE,		idle_cpu_nehalem),
1074 	INTEL_CPU_FAM6(WESTMERE_EP,		idle_cpu_nhx),
1075 	INTEL_CPU_FAM6(NEHALEM_EX,		idle_cpu_nhx),
1076 	INTEL_CPU_FAM6(ATOM_BONNELL,		idle_cpu_atom),
1077 	INTEL_CPU_FAM6(ATOM_BONNELL_MID,	idle_cpu_lincroft),
1078 	INTEL_CPU_FAM6(WESTMERE_EX,		idle_cpu_nhx),
1079 	INTEL_CPU_FAM6(SANDYBRIDGE,		idle_cpu_snb),
1080 	INTEL_CPU_FAM6(SANDYBRIDGE_X,		idle_cpu_snx),
1081 	INTEL_CPU_FAM6(ATOM_SALTWELL,		idle_cpu_atom),
1082 	INTEL_CPU_FAM6(ATOM_SILVERMONT,		idle_cpu_byt),
1083 	INTEL_CPU_FAM6(ATOM_SILVERMONT_MID,	idle_cpu_tangier),
1084 	INTEL_CPU_FAM6(ATOM_AIRMONT,		idle_cpu_cht),
1085 	INTEL_CPU_FAM6(IVYBRIDGE,		idle_cpu_ivb),
1086 	INTEL_CPU_FAM6(IVYBRIDGE_X,		idle_cpu_ivt),
1087 	INTEL_CPU_FAM6(HASWELL,			idle_cpu_hsw),
1088 	INTEL_CPU_FAM6(HASWELL_X,		idle_cpu_hsx),
1089 	INTEL_CPU_FAM6(HASWELL_L,		idle_cpu_hsw),
1090 	INTEL_CPU_FAM6(HASWELL_G,		idle_cpu_hsw),
1091 	INTEL_CPU_FAM6(ATOM_SILVERMONT_D,	idle_cpu_avn),
1092 	INTEL_CPU_FAM6(BROADWELL,		idle_cpu_bdw),
1093 	INTEL_CPU_FAM6(BROADWELL_G,		idle_cpu_bdw),
1094 	INTEL_CPU_FAM6(BROADWELL_X,		idle_cpu_bdx),
1095 	INTEL_CPU_FAM6(BROADWELL_D,		idle_cpu_bdx),
1096 	INTEL_CPU_FAM6(SKYLAKE_L,		idle_cpu_skl),
1097 	INTEL_CPU_FAM6(SKYLAKE,			idle_cpu_skl),
1098 	INTEL_CPU_FAM6(KABYLAKE_L,		idle_cpu_skl),
1099 	INTEL_CPU_FAM6(KABYLAKE,		idle_cpu_skl),
1100 	INTEL_CPU_FAM6(SKYLAKE_X,		idle_cpu_skx),
1101 	INTEL_CPU_FAM6(XEON_PHI_KNL,		idle_cpu_knl),
1102 	INTEL_CPU_FAM6(XEON_PHI_KNM,		idle_cpu_knl),
1103 	INTEL_CPU_FAM6(ATOM_GOLDMONT,		idle_cpu_bxt),
1104 	INTEL_CPU_FAM6(ATOM_GOLDMONT_PLUS,	idle_cpu_bxt),
1105 	INTEL_CPU_FAM6(ATOM_GOLDMONT_D,		idle_cpu_dnv),
1106 	INTEL_CPU_FAM6(ATOM_TREMONT_D,		idle_cpu_dnv),
1107 	{}
1108 };
1109 
1110 #define INTEL_CPU_FAM6_MWAIT \
1111 	{ X86_VENDOR_INTEL, 6, X86_MODEL_ANY, X86_FEATURE_MWAIT, 0 }
1112 
1113 static const struct x86_cpu_id intel_mwait_ids[] __initconst = {
1114 	INTEL_CPU_FAM6_MWAIT,
1115 	{}
1116 };
1117 
1118 static bool __init intel_idle_max_cstate_reached(int cstate)
1119 {
1120 	if (cstate + 1 > max_cstate) {
1121 		pr_info("max_cstate %d reached\n", max_cstate);
1122 		return true;
1123 	}
1124 	return false;
1125 }
1126 
1127 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
1128 #include <acpi/processor.h>
1129 
1130 static bool no_acpi __read_mostly;
1131 module_param(no_acpi, bool, 0444);
1132 MODULE_PARM_DESC(no_acpi, "Do not use ACPI _CST for building the idle states list");
1133 
1134 static struct acpi_processor_power acpi_state_table __initdata;
1135 
1136 /**
1137  * intel_idle_cst_usable - Check if the _CST information can be used.
1138  *
1139  * Check if all of the C-states listed by _CST in the max_cstate range are
1140  * ACPI_CSTATE_FFH, which means that they should be entered via MWAIT.
1141  */
1142 static bool __init intel_idle_cst_usable(void)
1143 {
1144 	int cstate, limit;
1145 
1146 	limit = min_t(int, min_t(int, CPUIDLE_STATE_MAX, max_cstate + 1),
1147 		      acpi_state_table.count);
1148 
1149 	for (cstate = 1; cstate < limit; cstate++) {
1150 		struct acpi_processor_cx *cx = &acpi_state_table.states[cstate];
1151 
1152 		if (cx->entry_method != ACPI_CSTATE_FFH)
1153 			return false;
1154 	}
1155 
1156 	return true;
1157 }
1158 
1159 static bool __init intel_idle_acpi_cst_extract(void)
1160 {
1161 	unsigned int cpu;
1162 
1163 	if (no_acpi) {
1164 		pr_debug("Not allowed to use ACPI _CST\n");
1165 		return false;
1166 	}
1167 
1168 	for_each_possible_cpu(cpu) {
1169 		struct acpi_processor *pr = per_cpu(processors, cpu);
1170 
1171 		if (!pr)
1172 			continue;
1173 
1174 		if (acpi_processor_evaluate_cst(pr->handle, cpu, &acpi_state_table))
1175 			continue;
1176 
1177 		acpi_state_table.count++;
1178 
1179 		if (!intel_idle_cst_usable())
1180 			continue;
1181 
1182 		if (!acpi_processor_claim_cst_control()) {
1183 			acpi_state_table.count = 0;
1184 			return false;
1185 		}
1186 
1187 		return true;
1188 	}
1189 
1190 	pr_debug("ACPI _CST not found or not usable\n");
1191 	return false;
1192 }
1193 
1194 static void __init intel_idle_init_cstates_acpi(struct cpuidle_driver *drv)
1195 {
1196 	int cstate, limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1197 
1198 	/*
1199 	 * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1200 	 * the interesting states are ACPI_CSTATE_FFH.
1201 	 */
1202 	for (cstate = 1; cstate < limit; cstate++) {
1203 		struct acpi_processor_cx *cx;
1204 		struct cpuidle_state *state;
1205 
1206 		if (intel_idle_max_cstate_reached(cstate))
1207 			break;
1208 
1209 		cx = &acpi_state_table.states[cstate];
1210 
1211 		state = &drv->states[drv->state_count++];
1212 
1213 		snprintf(state->name, CPUIDLE_NAME_LEN, "C%d_ACPI", cstate);
1214 		strlcpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
1215 		state->exit_latency = cx->latency;
1216 		/*
1217 		 * For C1-type C-states use the same number for both the exit
1218 		 * latency and target residency, because that is the case for
1219 		 * C1 in the majority of the static C-states tables above.
1220 		 * For the other types of C-states, however, set the target
1221 		 * residency to 3 times the exit latency which should lead to
1222 		 * a reasonable balance between energy-efficiency and
1223 		 * performance in the majority of interesting cases.
1224 		 */
1225 		state->target_residency = cx->latency;
1226 		if (cx->type > ACPI_STATE_C1)
1227 			state->target_residency *= 3;
1228 
1229 		state->flags = MWAIT2flg(cx->address);
1230 		if (cx->type > ACPI_STATE_C2)
1231 			state->flags |= CPUIDLE_FLAG_TLB_FLUSHED;
1232 
1233 		state->enter = intel_idle;
1234 		state->enter_s2idle = intel_idle_s2idle;
1235 	}
1236 }
1237 
1238 static bool __init intel_idle_off_by_default(u32 mwait_hint)
1239 {
1240 	int cstate, limit;
1241 
1242 	/*
1243 	 * If there are no _CST C-states, do not disable any C-states by
1244 	 * default.
1245 	 */
1246 	if (!acpi_state_table.count)
1247 		return false;
1248 
1249 	limit = min_t(int, CPUIDLE_STATE_MAX, acpi_state_table.count);
1250 	/*
1251 	 * If limit > 0, intel_idle_cst_usable() has returned 'true', so all of
1252 	 * the interesting states are ACPI_CSTATE_FFH.
1253 	 */
1254 	for (cstate = 1; cstate < limit; cstate++) {
1255 		if (acpi_state_table.states[cstate].address == mwait_hint)
1256 			return false;
1257 	}
1258 	return true;
1259 }
1260 #else /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1261 static inline bool intel_idle_acpi_cst_extract(void) { return false; }
1262 static inline void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { }
1263 static inline bool intel_idle_off_by_default(u32 mwait_hint) { return false; }
1264 #endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */
1265 
1266 /*
1267  * ivt_idle_state_table_update(void)
1268  *
1269  * Tune IVT multi-socket targets
1270  * Assumption: num_sockets == (max_package_num + 1)
1271  */
1272 static void __init ivt_idle_state_table_update(void)
1273 {
1274 	/* IVT uses a different table for 1-2, 3-4, and > 4 sockets */
1275 	int cpu, package_num, num_sockets = 1;
1276 
1277 	for_each_online_cpu(cpu) {
1278 		package_num = topology_physical_package_id(cpu);
1279 		if (package_num + 1 > num_sockets) {
1280 			num_sockets = package_num + 1;
1281 
1282 			if (num_sockets > 4) {
1283 				cpuidle_state_table = ivt_cstates_8s;
1284 				return;
1285 			}
1286 		}
1287 	}
1288 
1289 	if (num_sockets > 2)
1290 		cpuidle_state_table = ivt_cstates_4s;
1291 
1292 	/* else, 1 and 2 socket systems use default ivt_cstates */
1293 }
1294 
1295 /**
1296  * irtl_2_usec - IRTL to microseconds conversion.
1297  * @irtl: IRTL MSR value.
1298  *
1299  * Translate the IRTL (Interrupt Response Time Limit) MSR value to microseconds.
1300  */
1301 static unsigned long long __init irtl_2_usec(unsigned long long irtl)
1302 {
1303 	static const unsigned int irtl_ns_units[] __initconst = {
1304 		1, 32, 1024, 32768, 1048576, 33554432, 0, 0
1305 	};
1306 	unsigned long long ns;
1307 
1308 	if (!irtl)
1309 		return 0;
1310 
1311 	ns = irtl_ns_units[(irtl >> 10) & 0x7];
1312 
1313 	return div_u64((irtl & 0x3FF) * ns, NSEC_PER_USEC);
1314 }
1315 
1316 /*
1317  * bxt_idle_state_table_update(void)
1318  *
1319  * On BXT, we trust the IRTL to show the definitive maximum latency
1320  * We use the same value for target_residency.
1321  */
1322 static void __init bxt_idle_state_table_update(void)
1323 {
1324 	unsigned long long msr;
1325 	unsigned int usec;
1326 
1327 	rdmsrl(MSR_PKGC6_IRTL, msr);
1328 	usec = irtl_2_usec(msr);
1329 	if (usec) {
1330 		bxt_cstates[2].exit_latency = usec;
1331 		bxt_cstates[2].target_residency = usec;
1332 	}
1333 
1334 	rdmsrl(MSR_PKGC7_IRTL, msr);
1335 	usec = irtl_2_usec(msr);
1336 	if (usec) {
1337 		bxt_cstates[3].exit_latency = usec;
1338 		bxt_cstates[3].target_residency = usec;
1339 	}
1340 
1341 	rdmsrl(MSR_PKGC8_IRTL, msr);
1342 	usec = irtl_2_usec(msr);
1343 	if (usec) {
1344 		bxt_cstates[4].exit_latency = usec;
1345 		bxt_cstates[4].target_residency = usec;
1346 	}
1347 
1348 	rdmsrl(MSR_PKGC9_IRTL, msr);
1349 	usec = irtl_2_usec(msr);
1350 	if (usec) {
1351 		bxt_cstates[5].exit_latency = usec;
1352 		bxt_cstates[5].target_residency = usec;
1353 	}
1354 
1355 	rdmsrl(MSR_PKGC10_IRTL, msr);
1356 	usec = irtl_2_usec(msr);
1357 	if (usec) {
1358 		bxt_cstates[6].exit_latency = usec;
1359 		bxt_cstates[6].target_residency = usec;
1360 	}
1361 
1362 }
1363 /*
1364  * sklh_idle_state_table_update(void)
1365  *
1366  * On SKL-H (model 0x5e) disable C8 and C9 if:
1367  * C10 is enabled and SGX disabled
1368  */
1369 static void __init sklh_idle_state_table_update(void)
1370 {
1371 	unsigned long long msr;
1372 	unsigned int eax, ebx, ecx, edx;
1373 
1374 
1375 	/* if PC10 disabled via cmdline intel_idle.max_cstate=7 or shallower */
1376 	if (max_cstate <= 7)
1377 		return;
1378 
1379 	/* if PC10 not present in CPUID.MWAIT.EDX */
1380 	if ((mwait_substates & (0xF << 28)) == 0)
1381 		return;
1382 
1383 	rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr);
1384 
1385 	/* PC10 is not enabled in PKG C-state limit */
1386 	if ((msr & 0xF) != 8)
1387 		return;
1388 
1389 	ecx = 0;
1390 	cpuid(7, &eax, &ebx, &ecx, &edx);
1391 
1392 	/* if SGX is present */
1393 	if (ebx & (1 << 2)) {
1394 
1395 		rdmsrl(MSR_IA32_FEAT_CTL, msr);
1396 
1397 		/* if SGX is enabled */
1398 		if (msr & (1 << 18))
1399 			return;
1400 	}
1401 
1402 	skl_cstates[5].flags |= CPUIDLE_FLAG_UNUSABLE;	/* C8-SKL */
1403 	skl_cstates[6].flags |= CPUIDLE_FLAG_UNUSABLE;	/* C9-SKL */
1404 }
1405 
1406 static bool __init intel_idle_verify_cstate(unsigned int mwait_hint)
1407 {
1408 	unsigned int mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint) + 1;
1409 	unsigned int num_substates = (mwait_substates >> mwait_cstate * 4) &
1410 					MWAIT_SUBSTATE_MASK;
1411 
1412 	/* Ignore the C-state if there are NO sub-states in CPUID for it. */
1413 	if (num_substates == 0)
1414 		return false;
1415 
1416 	if (mwait_cstate > 2 && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
1417 		mark_tsc_unstable("TSC halts in idle states deeper than C2");
1418 
1419 	return true;
1420 }
1421 
1422 static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
1423 {
1424 	int cstate;
1425 
1426 	switch (boot_cpu_data.x86_model) {
1427 	case INTEL_FAM6_IVYBRIDGE_X:
1428 		ivt_idle_state_table_update();
1429 		break;
1430 	case INTEL_FAM6_ATOM_GOLDMONT:
1431 	case INTEL_FAM6_ATOM_GOLDMONT_PLUS:
1432 		bxt_idle_state_table_update();
1433 		break;
1434 	case INTEL_FAM6_SKYLAKE:
1435 		sklh_idle_state_table_update();
1436 		break;
1437 	}
1438 
1439 	for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
1440 		unsigned int mwait_hint;
1441 
1442 		if (intel_idle_max_cstate_reached(cstate))
1443 			break;
1444 
1445 		if (!cpuidle_state_table[cstate].enter &&
1446 		    !cpuidle_state_table[cstate].enter_s2idle)
1447 			break;
1448 
1449 		/* If marked as unusable, skip this state. */
1450 		if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_UNUSABLE) {
1451 			pr_debug("state %s is disabled\n",
1452 				 cpuidle_state_table[cstate].name);
1453 			continue;
1454 		}
1455 
1456 		mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags);
1457 		if (!intel_idle_verify_cstate(mwait_hint))
1458 			continue;
1459 
1460 		/* Structure copy. */
1461 		drv->states[drv->state_count] = cpuidle_state_table[cstate];
1462 
1463 		if (icpu->use_acpi && intel_idle_off_by_default(mwait_hint) &&
1464 		    !(cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_ALWAYS_ENABLE))
1465 			drv->states[drv->state_count].flags |= CPUIDLE_FLAG_OFF;
1466 
1467 		drv->state_count++;
1468 	}
1469 
1470 	if (icpu->byt_auto_demotion_disable_flag) {
1471 		wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
1472 		wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
1473 	}
1474 }
1475 
1476 /*
1477  * intel_idle_cpuidle_driver_init()
1478  * allocate, initialize cpuidle_states
1479  */
1480 static void __init intel_idle_cpuidle_driver_init(struct cpuidle_driver *drv)
1481 {
1482 	cpuidle_poll_state_init(drv);
1483 	drv->state_count = 1;
1484 
1485 	if (icpu)
1486 		intel_idle_init_cstates_icpu(drv);
1487 	else
1488 		intel_idle_init_cstates_acpi(drv);
1489 }
1490 
1491 static void auto_demotion_disable(void)
1492 {
1493 	unsigned long long msr_bits;
1494 
1495 	rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
1496 	msr_bits &= ~(icpu->auto_demotion_disable_flags);
1497 	wrmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
1498 }
1499 
1500 static void c1e_promotion_disable(void)
1501 {
1502 	unsigned long long msr_bits;
1503 
1504 	rdmsrl(MSR_IA32_POWER_CTL, msr_bits);
1505 	msr_bits &= ~0x2;
1506 	wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
1507 }
1508 
1509 /*
1510  * intel_idle_cpu_init()
1511  * allocate, initialize, register cpuidle_devices
1512  * @cpu: cpu/core to initialize
1513  */
1514 static int intel_idle_cpu_init(unsigned int cpu)
1515 {
1516 	struct cpuidle_device *dev;
1517 
1518 	dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
1519 	dev->cpu = cpu;
1520 
1521 	if (cpuidle_register_device(dev)) {
1522 		pr_debug("cpuidle_register_device %d failed!\n", cpu);
1523 		return -EIO;
1524 	}
1525 
1526 	if (!icpu)
1527 		return 0;
1528 
1529 	if (icpu->auto_demotion_disable_flags)
1530 		auto_demotion_disable();
1531 
1532 	if (icpu->disable_promotion_to_c1e)
1533 		c1e_promotion_disable();
1534 
1535 	return 0;
1536 }
1537 
1538 static int intel_idle_cpu_online(unsigned int cpu)
1539 {
1540 	struct cpuidle_device *dev;
1541 
1542 	if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE)
1543 		tick_broadcast_enable();
1544 
1545 	/*
1546 	 * Some systems can hotplug a cpu at runtime after
1547 	 * the kernel has booted, we have to initialize the
1548 	 * driver in this case
1549 	 */
1550 	dev = per_cpu_ptr(intel_idle_cpuidle_devices, cpu);
1551 	if (!dev->registered)
1552 		return intel_idle_cpu_init(cpu);
1553 
1554 	return 0;
1555 }
1556 
1557 /**
1558  * intel_idle_cpuidle_devices_uninit - Unregister all cpuidle devices.
1559  */
1560 static void __init intel_idle_cpuidle_devices_uninit(void)
1561 {
1562 	int i;
1563 
1564 	for_each_online_cpu(i)
1565 		cpuidle_unregister_device(per_cpu_ptr(intel_idle_cpuidle_devices, i));
1566 }
1567 
1568 static int __init intel_idle_init(void)
1569 {
1570 	const struct x86_cpu_id *id;
1571 	unsigned int eax, ebx, ecx;
1572 	int retval;
1573 
1574 	/* Do not load intel_idle at all for now if idle= is passed */
1575 	if (boot_option_idle_override != IDLE_NO_OVERRIDE)
1576 		return -ENODEV;
1577 
1578 	if (max_cstate == 0) {
1579 		pr_debug("disabled\n");
1580 		return -EPERM;
1581 	}
1582 
1583 	id = x86_match_cpu(intel_idle_ids);
1584 	if (id) {
1585 		if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
1586 			pr_debug("Please enable MWAIT in BIOS SETUP\n");
1587 			return -ENODEV;
1588 		}
1589 	} else {
1590 		id = x86_match_cpu(intel_mwait_ids);
1591 		if (!id)
1592 			return -ENODEV;
1593 	}
1594 
1595 	if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
1596 		return -ENODEV;
1597 
1598 	cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates);
1599 
1600 	if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
1601 	    !(ecx & CPUID5_ECX_INTERRUPT_BREAK) ||
1602 	    !mwait_substates)
1603 			return -ENODEV;
1604 
1605 	pr_debug("MWAIT substates: 0x%x\n", mwait_substates);
1606 
1607 	icpu = (const struct idle_cpu *)id->driver_data;
1608 	if (icpu) {
1609 		cpuidle_state_table = icpu->state_table;
1610 		if (icpu->use_acpi)
1611 			intel_idle_acpi_cst_extract();
1612 	} else if (!intel_idle_acpi_cst_extract()) {
1613 		return -ENODEV;
1614 	}
1615 
1616 	pr_debug("v" INTEL_IDLE_VERSION " model 0x%X\n",
1617 		 boot_cpu_data.x86_model);
1618 
1619 	intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
1620 	if (!intel_idle_cpuidle_devices)
1621 		return -ENOMEM;
1622 
1623 	intel_idle_cpuidle_driver_init(&intel_idle_driver);
1624 
1625 	retval = cpuidle_register_driver(&intel_idle_driver);
1626 	if (retval) {
1627 		struct cpuidle_driver *drv = cpuidle_get_driver();
1628 		printk(KERN_DEBUG pr_fmt("intel_idle yielding to %s\n"),
1629 		       drv ? drv->name : "none");
1630 		goto init_driver_fail;
1631 	}
1632 
1633 	if (boot_cpu_has(X86_FEATURE_ARAT))	/* Always Reliable APIC Timer */
1634 		lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE;
1635 
1636 	retval = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "idle/intel:online",
1637 				   intel_idle_cpu_online, NULL);
1638 	if (retval < 0)
1639 		goto hp_setup_fail;
1640 
1641 	pr_debug("lapic_timer_reliable_states 0x%x\n",
1642 		 lapic_timer_reliable_states);
1643 
1644 	return 0;
1645 
1646 hp_setup_fail:
1647 	intel_idle_cpuidle_devices_uninit();
1648 	cpuidle_unregister_driver(&intel_idle_driver);
1649 init_driver_fail:
1650 	free_percpu(intel_idle_cpuidle_devices);
1651 	return retval;
1652 
1653 }
1654 device_initcall(intel_idle_init);
1655 
1656 /*
1657  * We are not really modular, but we used to support that.  Meaning we also
1658  * support "intel_idle.max_cstate=..." at boot and also a read-only export of
1659  * it at /sys/module/intel_idle/parameters/max_cstate -- so using module_param
1660  * is the easiest way (currently) to continue doing that.
1661  */
1662 module_param(max_cstate, int, 0444);
1663