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31#include <linux/module.h>
32#include <linux/acpi.h>
33#include <linux/dmi.h>
34#include <linux/sched.h>
35#include <linux/tick.h>
36#include <linux/cpuidle.h>
37#include <linux/syscore_ops.h>
38#include <acpi/processor.h>
39
40
41
42
43
44
45
46#ifdef CONFIG_X86
47#include <asm/apic.h>
48#endif
49
50#define PREFIX "ACPI: "
51
52#define ACPI_PROCESSOR_CLASS "processor"
53#define _COMPONENT ACPI_PROCESSOR_COMPONENT
54ACPI_MODULE_NAME("processor_idle");
55
56static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER;
57module_param(max_cstate, uint, 0000);
58static unsigned int nocst __read_mostly;
59module_param(nocst, uint, 0000);
60static int bm_check_disable __read_mostly;
61module_param(bm_check_disable, uint, 0000);
62
63static unsigned int latency_factor __read_mostly = 2;
64module_param(latency_factor, uint, 0644);
65
66static DEFINE_PER_CPU(struct cpuidle_device *, acpi_cpuidle_device);
67
68static DEFINE_PER_CPU(struct acpi_processor_cx * [CPUIDLE_STATE_MAX],
69 acpi_cstate);
70
71static int disabled_by_idle_boot_param(void)
72{
73 return boot_option_idle_override == IDLE_POLL ||
74 boot_option_idle_override == IDLE_HALT;
75}
76
77
78
79
80
81
82
83static int set_max_cstate(const struct dmi_system_id *id)
84{
85 if (max_cstate > ACPI_PROCESSOR_MAX_POWER)
86 return 0;
87
88 printk(KERN_NOTICE PREFIX "%s detected - limiting to C%ld max_cstate."
89 " Override with \"processor.max_cstate=%d\"\n", id->ident,
90 (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1);
91
92 max_cstate = (long)id->driver_data;
93
94 return 0;
95}
96
97static struct dmi_system_id processor_power_dmi_table[] = {
98 { set_max_cstate, "Clevo 5600D", {
99 DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"),
100 DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")},
101 (void *)2},
102 { set_max_cstate, "Pavilion zv5000", {
103 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
104 DMI_MATCH(DMI_PRODUCT_NAME,"Pavilion zv5000 (DS502A#ABA)")},
105 (void *)1},
106 { set_max_cstate, "Asus L8400B", {
107 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
108 DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")},
109 (void *)1},
110 {},
111};
112
113
114
115
116
117
118static void acpi_safe_halt(void)
119{
120 if (!tif_need_resched()) {
121 safe_halt();
122 local_irq_disable();
123 }
124}
125
126#ifdef ARCH_APICTIMER_STOPS_ON_C3
127
128
129
130
131
132
133
134static void lapic_timer_check_state(int state, struct acpi_processor *pr,
135 struct acpi_processor_cx *cx)
136{
137 struct acpi_processor_power *pwr = &pr->power;
138 u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2;
139
140 if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT))
141 return;
142
143 if (amd_e400_c1e_detected)
144 type = ACPI_STATE_C1;
145
146
147
148
149
150 if (pwr->timer_broadcast_on_state < state)
151 return;
152
153 if (cx->type >= type)
154 pr->power.timer_broadcast_on_state = state;
155}
156
157static void __lapic_timer_propagate_broadcast(void *arg)
158{
159 struct acpi_processor *pr = (struct acpi_processor *) arg;
160
161 if (pr->power.timer_broadcast_on_state < INT_MAX)
162 tick_broadcast_enable();
163 else
164 tick_broadcast_disable();
165}
166
167static void lapic_timer_propagate_broadcast(struct acpi_processor *pr)
168{
169 smp_call_function_single(pr->id, __lapic_timer_propagate_broadcast,
170 (void *)pr, 1);
171}
172
173
174static void lapic_timer_state_broadcast(struct acpi_processor *pr,
175 struct acpi_processor_cx *cx,
176 int broadcast)
177{
178 int state = cx - pr->power.states;
179
180 if (state >= pr->power.timer_broadcast_on_state) {
181 if (broadcast)
182 tick_broadcast_enter();
183 else
184 tick_broadcast_exit();
185 }
186}
187
188#else
189
190static void lapic_timer_check_state(int state, struct acpi_processor *pr,
191 struct acpi_processor_cx *cstate) { }
192static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { }
193static void lapic_timer_state_broadcast(struct acpi_processor *pr,
194 struct acpi_processor_cx *cx,
195 int broadcast)
196{
197}
198
199#endif
200
201#ifdef CONFIG_PM_SLEEP
202static u32 saved_bm_rld;
203
204static int acpi_processor_suspend(void)
205{
206 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld);
207 return 0;
208}
209
210static void acpi_processor_resume(void)
211{
212 u32 resumed_bm_rld = 0;
213
214 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld);
215 if (resumed_bm_rld == saved_bm_rld)
216 return;
217
218 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
219}
220
221static struct syscore_ops acpi_processor_syscore_ops = {
222 .suspend = acpi_processor_suspend,
223 .resume = acpi_processor_resume,
224};
225
226void acpi_processor_syscore_init(void)
227{
228 register_syscore_ops(&acpi_processor_syscore_ops);
229}
230
231void acpi_processor_syscore_exit(void)
232{
233 unregister_syscore_ops(&acpi_processor_syscore_ops);
234}
235#endif
236
237#if defined(CONFIG_X86)
238static void tsc_check_state(int state)
239{
240 switch (boot_cpu_data.x86_vendor) {
241 case X86_VENDOR_AMD:
242 case X86_VENDOR_INTEL:
243
244
245
246
247 if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
248 return;
249
250
251 default:
252
253 if (state > ACPI_STATE_C1)
254 mark_tsc_unstable("TSC halts in idle");
255 }
256}
257#else
258static void tsc_check_state(int state) { return; }
259#endif
260
261static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr)
262{
263
264 if (!pr->pblk)
265 return -ENODEV;
266
267
268 pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2;
269 pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3;
270
271#ifndef CONFIG_HOTPLUG_CPU
272
273
274
275
276 if ((num_online_cpus() > 1) &&
277 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED))
278 return -ENODEV;
279#endif
280
281
282 pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4;
283 pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5;
284
285
286 pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.c2_latency;
287 pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.c3_latency;
288
289
290
291
292
293 if (acpi_gbl_FADT.c2_latency > ACPI_PROCESSOR_MAX_C2_LATENCY) {
294 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
295 "C2 latency too large [%d]\n", acpi_gbl_FADT.c2_latency));
296
297 pr->power.states[ACPI_STATE_C2].address = 0;
298 }
299
300
301
302
303
304 if (acpi_gbl_FADT.c3_latency > ACPI_PROCESSOR_MAX_C3_LATENCY) {
305 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
306 "C3 latency too large [%d]\n", acpi_gbl_FADT.c3_latency));
307
308 pr->power.states[ACPI_STATE_C3].address = 0;
309 }
310
311 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
312 "lvl2[0x%08x] lvl3[0x%08x]\n",
313 pr->power.states[ACPI_STATE_C2].address,
314 pr->power.states[ACPI_STATE_C3].address));
315
316 return 0;
317}
318
319static int acpi_processor_get_power_info_default(struct acpi_processor *pr)
320{
321 if (!pr->power.states[ACPI_STATE_C1].valid) {
322
323
324 pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1;
325 pr->power.states[ACPI_STATE_C1].valid = 1;
326 pr->power.states[ACPI_STATE_C1].entry_method = ACPI_CSTATE_HALT;
327 }
328
329 pr->power.states[ACPI_STATE_C0].valid = 1;
330 return 0;
331}
332
333static int acpi_processor_get_power_info_cst(struct acpi_processor *pr)
334{
335 acpi_status status;
336 u64 count;
337 int current_count;
338 int i, ret = 0;
339 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
340 union acpi_object *cst;
341
342
343 if (nocst)
344 return -ENODEV;
345
346 current_count = 0;
347
348 status = acpi_evaluate_object(pr->handle, "_CST", NULL, &buffer);
349 if (ACPI_FAILURE(status)) {
350 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No _CST, giving up\n"));
351 return -ENODEV;
352 }
353
354 cst = buffer.pointer;
355
356
357 if (!cst || (cst->type != ACPI_TYPE_PACKAGE) || cst->package.count < 2) {
358 printk(KERN_ERR PREFIX "not enough elements in _CST\n");
359 ret = -EFAULT;
360 goto end;
361 }
362
363 count = cst->package.elements[0].integer.value;
364
365
366 if (count < 1 || count != cst->package.count - 1) {
367 printk(KERN_ERR PREFIX "count given by _CST is not valid\n");
368 ret = -EFAULT;
369 goto end;
370 }
371
372
373 pr->flags.has_cst = 1;
374
375 for (i = 1; i <= count; i++) {
376 union acpi_object *element;
377 union acpi_object *obj;
378 struct acpi_power_register *reg;
379 struct acpi_processor_cx cx;
380
381 memset(&cx, 0, sizeof(cx));
382
383 element = &(cst->package.elements[i]);
384 if (element->type != ACPI_TYPE_PACKAGE)
385 continue;
386
387 if (element->package.count != 4)
388 continue;
389
390 obj = &(element->package.elements[0]);
391
392 if (obj->type != ACPI_TYPE_BUFFER)
393 continue;
394
395 reg = (struct acpi_power_register *)obj->buffer.pointer;
396
397 if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO &&
398 (reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE))
399 continue;
400
401
402 obj = &(element->package.elements[1]);
403 if (obj->type != ACPI_TYPE_INTEGER)
404 continue;
405
406 cx.type = obj->integer.value;
407
408
409
410
411 if (i == 1 && cx.type != ACPI_STATE_C1)
412 current_count++;
413
414 cx.address = reg->address;
415 cx.index = current_count + 1;
416
417 cx.entry_method = ACPI_CSTATE_SYSTEMIO;
418 if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
419 if (acpi_processor_ffh_cstate_probe
420 (pr->id, &cx, reg) == 0) {
421 cx.entry_method = ACPI_CSTATE_FFH;
422 } else if (cx.type == ACPI_STATE_C1) {
423
424
425
426
427
428
429 cx.entry_method = ACPI_CSTATE_HALT;
430 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
431 } else {
432 continue;
433 }
434 if (cx.type == ACPI_STATE_C1 &&
435 (boot_option_idle_override == IDLE_NOMWAIT)) {
436
437
438
439
440
441
442
443
444
445
446 cx.entry_method = ACPI_CSTATE_HALT;
447 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
448 }
449 } else {
450 snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
451 cx.address);
452 }
453
454 if (cx.type == ACPI_STATE_C1) {
455 cx.valid = 1;
456 }
457
458 obj = &(element->package.elements[2]);
459 if (obj->type != ACPI_TYPE_INTEGER)
460 continue;
461
462 cx.latency = obj->integer.value;
463
464 obj = &(element->package.elements[3]);
465 if (obj->type != ACPI_TYPE_INTEGER)
466 continue;
467
468 current_count++;
469 memcpy(&(pr->power.states[current_count]), &cx, sizeof(cx));
470
471
472
473
474
475 if (current_count >= (ACPI_PROCESSOR_MAX_POWER - 1)) {
476 printk(KERN_WARNING
477 "Limiting number of power states to max (%d)\n",
478 ACPI_PROCESSOR_MAX_POWER);
479 printk(KERN_WARNING
480 "Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
481 break;
482 }
483 }
484
485 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d power states\n",
486 current_count));
487
488
489 if (current_count < 2)
490 ret = -EFAULT;
491
492 end:
493 kfree(buffer.pointer);
494
495 return ret;
496}
497
498static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
499 struct acpi_processor_cx *cx)
500{
501 static int bm_check_flag = -1;
502 static int bm_control_flag = -1;
503
504
505 if (!cx->address)
506 return;
507
508
509
510
511
512
513
514
515 else if (errata.piix4.fdma) {
516 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
517 "C3 not supported on PIIX4 with Type-F DMA\n"));
518 return;
519 }
520
521
522 if (bm_check_flag == -1) {
523
524 acpi_processor_power_init_bm_check(&(pr->flags), pr->id);
525 bm_check_flag = pr->flags.bm_check;
526 bm_control_flag = pr->flags.bm_control;
527 } else {
528 pr->flags.bm_check = bm_check_flag;
529 pr->flags.bm_control = bm_control_flag;
530 }
531
532 if (pr->flags.bm_check) {
533 if (!pr->flags.bm_control) {
534 if (pr->flags.has_cst != 1) {
535
536 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
537 "C3 support requires BM control\n"));
538 return;
539 } else {
540
541 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
542 "C3 support without BM control\n"));
543 }
544 }
545 } else {
546
547
548
549
550 if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) {
551 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
552 "Cache invalidation should work properly"
553 " for C3 to be enabled on SMP systems\n"));
554 return;
555 }
556 }
557
558
559
560
561
562
563
564 cx->valid = 1;
565
566
567
568
569
570
571
572
573
574 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 1);
575
576 return;
577}
578
579static int acpi_processor_power_verify(struct acpi_processor *pr)
580{
581 unsigned int i;
582 unsigned int working = 0;
583
584 pr->power.timer_broadcast_on_state = INT_MAX;
585
586 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
587 struct acpi_processor_cx *cx = &pr->power.states[i];
588
589 switch (cx->type) {
590 case ACPI_STATE_C1:
591 cx->valid = 1;
592 break;
593
594 case ACPI_STATE_C2:
595 if (!cx->address)
596 break;
597 cx->valid = 1;
598 break;
599
600 case ACPI_STATE_C3:
601 acpi_processor_power_verify_c3(pr, cx);
602 break;
603 }
604 if (!cx->valid)
605 continue;
606
607 lapic_timer_check_state(i, pr, cx);
608 tsc_check_state(cx->type);
609 working++;
610 }
611
612 lapic_timer_propagate_broadcast(pr);
613
614 return (working);
615}
616
617static int acpi_processor_get_power_info(struct acpi_processor *pr)
618{
619 unsigned int i;
620 int result;
621
622
623
624
625
626
627 memset(pr->power.states, 0, sizeof(pr->power.states));
628
629 result = acpi_processor_get_power_info_cst(pr);
630 if (result == -ENODEV)
631 result = acpi_processor_get_power_info_fadt(pr);
632
633 if (result)
634 return result;
635
636 acpi_processor_get_power_info_default(pr);
637
638 pr->power.count = acpi_processor_power_verify(pr);
639
640
641
642
643
644 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) {
645 if (pr->power.states[i].valid) {
646 pr->power.count = i;
647 if (pr->power.states[i].type >= ACPI_STATE_C2)
648 pr->flags.power = 1;
649 }
650 }
651
652 return 0;
653}
654
655
656
657
658static int acpi_idle_bm_check(void)
659{
660 u32 bm_status = 0;
661
662 if (bm_check_disable)
663 return 0;
664
665 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status);
666 if (bm_status)
667 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);
668
669
670
671
672
673 else if (errata.piix4.bmisx) {
674 if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01)
675 || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))
676 bm_status = 1;
677 }
678 return bm_status;
679}
680
681
682
683
684
685
686
687static void acpi_idle_do_entry(struct acpi_processor_cx *cx)
688{
689 if (cx->entry_method == ACPI_CSTATE_FFH) {
690
691 acpi_processor_ffh_cstate_enter(cx);
692 } else if (cx->entry_method == ACPI_CSTATE_HALT) {
693 acpi_safe_halt();
694 } else {
695
696 inb(cx->address);
697
698
699
700 inl(acpi_gbl_FADT.xpm_timer_block.address);
701 }
702}
703
704
705
706
707
708
709static int acpi_idle_play_dead(struct cpuidle_device *dev, int index)
710{
711 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
712
713 ACPI_FLUSH_CPU_CACHE();
714
715 while (1) {
716
717 if (cx->entry_method == ACPI_CSTATE_HALT)
718 safe_halt();
719 else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {
720 inb(cx->address);
721
722 inl(acpi_gbl_FADT.xpm_timer_block.address);
723 } else
724 return -ENODEV;
725 }
726
727
728 return 0;
729}
730
731static bool acpi_idle_fallback_to_c1(struct acpi_processor *pr)
732{
733 return IS_ENABLED(CONFIG_HOTPLUG_CPU) && !pr->flags.has_cst &&
734 !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED);
735}
736
737static int c3_cpu_count;
738static DEFINE_RAW_SPINLOCK(c3_lock);
739
740
741
742
743
744
745
746static void acpi_idle_enter_bm(struct acpi_processor *pr,
747 struct acpi_processor_cx *cx, bool timer_bc)
748{
749 acpi_unlazy_tlb(smp_processor_id());
750
751
752
753
754
755 if (timer_bc)
756 lapic_timer_state_broadcast(pr, cx, 1);
757
758
759
760
761
762
763
764
765
766
767 if (pr->flags.bm_control) {
768 raw_spin_lock(&c3_lock);
769 c3_cpu_count++;
770
771 if (c3_cpu_count == num_online_cpus())
772 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1);
773 raw_spin_unlock(&c3_lock);
774 }
775
776 acpi_idle_do_entry(cx);
777
778
779 if (pr->flags.bm_control) {
780 raw_spin_lock(&c3_lock);
781 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0);
782 c3_cpu_count--;
783 raw_spin_unlock(&c3_lock);
784 }
785
786 if (timer_bc)
787 lapic_timer_state_broadcast(pr, cx, 0);
788}
789
790static int acpi_idle_enter(struct cpuidle_device *dev,
791 struct cpuidle_driver *drv, int index)
792{
793 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
794 struct acpi_processor *pr;
795
796 pr = __this_cpu_read(processors);
797 if (unlikely(!pr))
798 return -EINVAL;
799
800 if (cx->type != ACPI_STATE_C1) {
801 if (acpi_idle_fallback_to_c1(pr) && num_online_cpus() > 1) {
802 index = CPUIDLE_DRIVER_STATE_START;
803 cx = per_cpu(acpi_cstate[index], dev->cpu);
804 } else if (cx->type == ACPI_STATE_C3 && pr->flags.bm_check) {
805 if (cx->bm_sts_skip || !acpi_idle_bm_check()) {
806 acpi_idle_enter_bm(pr, cx, true);
807 return index;
808 } else if (drv->safe_state_index >= 0) {
809 index = drv->safe_state_index;
810 cx = per_cpu(acpi_cstate[index], dev->cpu);
811 } else {
812 acpi_safe_halt();
813 return -EBUSY;
814 }
815 }
816 }
817
818 lapic_timer_state_broadcast(pr, cx, 1);
819
820 if (cx->type == ACPI_STATE_C3)
821 ACPI_FLUSH_CPU_CACHE();
822
823 acpi_idle_do_entry(cx);
824
825 lapic_timer_state_broadcast(pr, cx, 0);
826
827 return index;
828}
829
830static void acpi_idle_enter_freeze(struct cpuidle_device *dev,
831 struct cpuidle_driver *drv, int index)
832{
833 struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu);
834
835 if (cx->type == ACPI_STATE_C3) {
836 struct acpi_processor *pr = __this_cpu_read(processors);
837
838 if (unlikely(!pr))
839 return;
840
841 if (pr->flags.bm_check) {
842 acpi_idle_enter_bm(pr, cx, false);
843 return;
844 } else {
845 ACPI_FLUSH_CPU_CACHE();
846 }
847 }
848 acpi_idle_do_entry(cx);
849}
850
851struct cpuidle_driver acpi_idle_driver = {
852 .name = "acpi_idle",
853 .owner = THIS_MODULE,
854};
855
856
857
858
859
860
861
862
863static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
864 struct cpuidle_device *dev)
865{
866 int i, count = CPUIDLE_DRIVER_STATE_START;
867 struct acpi_processor_cx *cx;
868
869 if (!pr->flags.power_setup_done)
870 return -EINVAL;
871
872 if (pr->flags.power == 0) {
873 return -EINVAL;
874 }
875
876 if (!dev)
877 return -EINVAL;
878
879 dev->cpu = pr->id;
880
881 if (max_cstate == 0)
882 max_cstate = 1;
883
884 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
885 cx = &pr->power.states[i];
886
887 if (!cx->valid)
888 continue;
889
890 per_cpu(acpi_cstate[count], dev->cpu) = cx;
891
892 count++;
893 if (count == CPUIDLE_STATE_MAX)
894 break;
895 }
896
897 if (!count)
898 return -EINVAL;
899
900 return 0;
901}
902
903
904
905
906
907
908
909static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
910{
911 int i, count = CPUIDLE_DRIVER_STATE_START;
912 struct acpi_processor_cx *cx;
913 struct cpuidle_state *state;
914 struct cpuidle_driver *drv = &acpi_idle_driver;
915
916 if (!pr->flags.power_setup_done)
917 return -EINVAL;
918
919 if (pr->flags.power == 0)
920 return -EINVAL;
921
922 drv->safe_state_index = -1;
923 for (i = CPUIDLE_DRIVER_STATE_START; i < CPUIDLE_STATE_MAX; i++) {
924 drv->states[i].name[0] = '\0';
925 drv->states[i].desc[0] = '\0';
926 }
927
928 if (max_cstate == 0)
929 max_cstate = 1;
930
931 for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
932 cx = &pr->power.states[i];
933
934 if (!cx->valid)
935 continue;
936
937 state = &drv->states[count];
938 snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i);
939 strncpy(state->desc, cx->desc, CPUIDLE_DESC_LEN);
940 state->exit_latency = cx->latency;
941 state->target_residency = cx->latency * latency_factor;
942 state->enter = acpi_idle_enter;
943
944 state->flags = 0;
945 if (cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2) {
946 state->enter_dead = acpi_idle_play_dead;
947 drv->safe_state_index = count;
948 }
949
950
951
952
953
954
955
956 if (cx->type != ACPI_STATE_C1 && !acpi_idle_fallback_to_c1(pr))
957 state->enter_freeze = acpi_idle_enter_freeze;
958
959 count++;
960 if (count == CPUIDLE_STATE_MAX)
961 break;
962 }
963
964 drv->state_count = count;
965
966 if (!count)
967 return -EINVAL;
968
969 return 0;
970}
971
972int acpi_processor_hotplug(struct acpi_processor *pr)
973{
974 int ret = 0;
975 struct cpuidle_device *dev;
976
977 if (disabled_by_idle_boot_param())
978 return 0;
979
980 if (nocst)
981 return -ENODEV;
982
983 if (!pr->flags.power_setup_done)
984 return -ENODEV;
985
986 dev = per_cpu(acpi_cpuidle_device, pr->id);
987 cpuidle_pause_and_lock();
988 cpuidle_disable_device(dev);
989 acpi_processor_get_power_info(pr);
990 if (pr->flags.power) {
991 acpi_processor_setup_cpuidle_cx(pr, dev);
992 ret = cpuidle_enable_device(dev);
993 }
994 cpuidle_resume_and_unlock();
995
996 return ret;
997}
998
999int acpi_processor_cst_has_changed(struct acpi_processor *pr)
1000{
1001 int cpu;
1002 struct acpi_processor *_pr;
1003 struct cpuidle_device *dev;
1004
1005 if (disabled_by_idle_boot_param())
1006 return 0;
1007
1008 if (nocst)
1009 return -ENODEV;
1010
1011 if (!pr->flags.power_setup_done)
1012 return -ENODEV;
1013
1014
1015
1016
1017
1018
1019
1020 if (pr->id == 0 && cpuidle_get_driver() == &acpi_idle_driver) {
1021
1022
1023 get_online_cpus();
1024 cpuidle_pause_and_lock();
1025
1026
1027 for_each_online_cpu(cpu) {
1028 _pr = per_cpu(processors, cpu);
1029 if (!_pr || !_pr->flags.power_setup_done)
1030 continue;
1031 dev = per_cpu(acpi_cpuidle_device, cpu);
1032 cpuidle_disable_device(dev);
1033 }
1034
1035
1036 acpi_processor_get_power_info(pr);
1037 acpi_processor_setup_cpuidle_states(pr);
1038
1039
1040 for_each_online_cpu(cpu) {
1041 _pr = per_cpu(processors, cpu);
1042 if (!_pr || !_pr->flags.power_setup_done)
1043 continue;
1044 acpi_processor_get_power_info(_pr);
1045 if (_pr->flags.power) {
1046 dev = per_cpu(acpi_cpuidle_device, cpu);
1047 acpi_processor_setup_cpuidle_cx(_pr, dev);
1048 cpuidle_enable_device(dev);
1049 }
1050 }
1051 cpuidle_resume_and_unlock();
1052 put_online_cpus();
1053 }
1054
1055 return 0;
1056}
1057
1058static int acpi_processor_registered;
1059
1060int acpi_processor_power_init(struct acpi_processor *pr)
1061{
1062 acpi_status status;
1063 int retval;
1064 struct cpuidle_device *dev;
1065 static int first_run;
1066
1067 if (disabled_by_idle_boot_param())
1068 return 0;
1069
1070 if (!first_run) {
1071 dmi_check_system(processor_power_dmi_table);
1072 max_cstate = acpi_processor_cstate_check(max_cstate);
1073 if (max_cstate < ACPI_C_STATES_MAX)
1074 printk(KERN_NOTICE
1075 "ACPI: processor limited to max C-state %d\n",
1076 max_cstate);
1077 first_run++;
1078 }
1079
1080 if (acpi_gbl_FADT.cst_control && !nocst) {
1081 status =
1082 acpi_os_write_port(acpi_gbl_FADT.smi_command, acpi_gbl_FADT.cst_control, 8);
1083 if (ACPI_FAILURE(status)) {
1084 ACPI_EXCEPTION((AE_INFO, status,
1085 "Notifying BIOS of _CST ability failed"));
1086 }
1087 }
1088
1089 acpi_processor_get_power_info(pr);
1090 pr->flags.power_setup_done = 1;
1091
1092
1093
1094
1095
1096
1097 if (pr->flags.power) {
1098
1099 if (!acpi_processor_registered) {
1100 acpi_processor_setup_cpuidle_states(pr);
1101 retval = cpuidle_register_driver(&acpi_idle_driver);
1102 if (retval)
1103 return retval;
1104 printk(KERN_DEBUG "ACPI: %s registered with cpuidle\n",
1105 acpi_idle_driver.name);
1106 }
1107
1108 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1109 if (!dev)
1110 return -ENOMEM;
1111 per_cpu(acpi_cpuidle_device, pr->id) = dev;
1112
1113 acpi_processor_setup_cpuidle_cx(pr, dev);
1114
1115
1116
1117
1118 retval = cpuidle_register_device(dev);
1119 if (retval) {
1120 if (acpi_processor_registered == 0)
1121 cpuidle_unregister_driver(&acpi_idle_driver);
1122 return retval;
1123 }
1124 acpi_processor_registered++;
1125 }
1126 return 0;
1127}
1128
1129int acpi_processor_power_exit(struct acpi_processor *pr)
1130{
1131 struct cpuidle_device *dev = per_cpu(acpi_cpuidle_device, pr->id);
1132
1133 if (disabled_by_idle_boot_param())
1134 return 0;
1135
1136 if (pr->flags.power) {
1137 cpuidle_unregister_device(dev);
1138 acpi_processor_registered--;
1139 if (acpi_processor_registered == 0)
1140 cpuidle_unregister_driver(&acpi_idle_driver);
1141 }
1142
1143 pr->flags.power_setup_done = 0;
1144 return 0;
1145}
1146