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PM / sleep: Asynchronous threads for suspend_noirq
[linux/fpc-iii.git] / drivers / acpi / processor_throttling.c
blob28baa05b8018dd6c6e6e1db93c1a5ceed74d4d74
1 /*
2 * processor_throttling.c - Throttling submodule of the ACPI processor driver
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * - Added processor hotplug support
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or (at
15 * your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 *
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 */
28
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/slab.h>
32 #include <linux/init.h>
33 #include <linux/sched.h>
34 #include <linux/cpufreq.h>
35 #include <linux/acpi.h>
36 #include <acpi/processor.h>
37 #include <asm/io.h>
38 #include <asm/uaccess.h>
39
40 #define PREFIX "ACPI: "
41
42 #define ACPI_PROCESSOR_CLASS "processor"
43 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
44 ACPI_MODULE_NAME("processor_throttling");
45
46 /* ignore_tpc:
47 * 0 -> acpi processor driver doesn't ignore _TPC values
48 * 1 -> acpi processor driver ignores _TPC values
49 */
50 static int ignore_tpc;
51 module_param(ignore_tpc, int, 0644);
52 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
53
54 struct throttling_tstate {
55 unsigned int cpu; /* cpu nr */
56 int target_state; /* target T-state */
57 };
58
59 #define THROTTLING_PRECHANGE (1)
60 #define THROTTLING_POSTCHANGE (2)
61
62 static int acpi_processor_get_throttling(struct acpi_processor *pr);
63 int acpi_processor_set_throttling(struct acpi_processor *pr,
64 int state, bool force);
65
66 static int acpi_processor_update_tsd_coord(void)
67 {
68 int count, count_target;
69 int retval = 0;
70 unsigned int i, j;
71 cpumask_var_t covered_cpus;
72 struct acpi_processor *pr, *match_pr;
73 struct acpi_tsd_package *pdomain, *match_pdomain;
74 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
75
76 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
77 return -ENOMEM;
78
79 /*
80 * Now that we have _TSD data from all CPUs, lets setup T-state
81 * coordination between all CPUs.
82 */
83 for_each_possible_cpu(i) {
84 pr = per_cpu(processors, i);
85 if (!pr)
86 continue;
87
88 /* Basic validity check for domain info */
89 pthrottling = &(pr->throttling);
90
91 /*
92 * If tsd package for one cpu is invalid, the coordination
93 * among all CPUs is thought as invalid.
94 * Maybe it is ugly.
95 */
96 if (!pthrottling->tsd_valid_flag) {
97 retval = -EINVAL;
98 break;
99 }
100 }
101 if (retval)
102 goto err_ret;
103
104 for_each_possible_cpu(i) {
105 pr = per_cpu(processors, i);
106 if (!pr)
107 continue;
108
109 if (cpumask_test_cpu(i, covered_cpus))
110 continue;
111 pthrottling = &pr->throttling;
112
113 pdomain = &(pthrottling->domain_info);
114 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
115 cpumask_set_cpu(i, covered_cpus);
116 /*
117 * If the number of processor in the TSD domain is 1, it is
118 * unnecessary to parse the coordination for this CPU.
119 */
120 if (pdomain->num_processors <= 1)
121 continue;
122
123 /* Validate the Domain info */
124 count_target = pdomain->num_processors;
125 count = 1;
126
127 for_each_possible_cpu(j) {
128 if (i == j)
129 continue;
130
131 match_pr = per_cpu(processors, j);
132 if (!match_pr)
133 continue;
134
135 match_pthrottling = &(match_pr->throttling);
136 match_pdomain = &(match_pthrottling->domain_info);
137 if (match_pdomain->domain != pdomain->domain)
138 continue;
139
140 /* Here i and j are in the same domain.
141 * If two TSD packages have the same domain, they
142 * should have the same num_porcessors and
143 * coordination type. Otherwise it will be regarded
144 * as illegal.
145 */
146 if (match_pdomain->num_processors != count_target) {
147 retval = -EINVAL;
148 goto err_ret;
149 }
150
151 if (pdomain->coord_type != match_pdomain->coord_type) {
152 retval = -EINVAL;
153 goto err_ret;
154 }
155
156 cpumask_set_cpu(j, covered_cpus);
157 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
158 count++;
159 }
160 for_each_possible_cpu(j) {
161 if (i == j)
162 continue;
163
164 match_pr = per_cpu(processors, j);
165 if (!match_pr)
166 continue;
167
168 match_pthrottling = &(match_pr->throttling);
169 match_pdomain = &(match_pthrottling->domain_info);
170 if (match_pdomain->domain != pdomain->domain)
171 continue;
172
173 /*
174 * If some CPUS have the same domain, they
175 * will have the same shared_cpu_map.
176 */
177 cpumask_copy(match_pthrottling->shared_cpu_map,
178 pthrottling->shared_cpu_map);
179 }
180 }
181
182 err_ret:
183 free_cpumask_var(covered_cpus);
184
185 for_each_possible_cpu(i) {
186 pr = per_cpu(processors, i);
187 if (!pr)
188 continue;
189
190 /*
191 * Assume no coordination on any error parsing domain info.
192 * The coordination type will be forced as SW_ALL.
193 */
194 if (retval) {
195 pthrottling = &(pr->throttling);
196 cpumask_clear(pthrottling->shared_cpu_map);
197 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
198 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
199 }
200 }
201
202 return retval;
203 }
204
205 /*
206 * Update the T-state coordination after the _TSD
207 * data for all cpus is obtained.
208 */
209 void acpi_processor_throttling_init(void)
210 {
211 if (acpi_processor_update_tsd_coord()) {
212 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
213 "Assume no T-state coordination\n"));
214 }
215
216 return;
217 }
218
219 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
220 {
221 struct throttling_tstate *p_tstate = data;
222 struct acpi_processor *pr;
223 unsigned int cpu ;
224 int target_state;
225 struct acpi_processor_limit *p_limit;
226 struct acpi_processor_throttling *p_throttling;
227
228 cpu = p_tstate->cpu;
229 pr = per_cpu(processors, cpu);
230 if (!pr) {
231 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
232 return 0;
233 }
234 if (!pr->flags.throttling) {
235 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
236 "unsupported on CPU %d\n", cpu));
237 return 0;
238 }
239 target_state = p_tstate->target_state;
240 p_throttling = &(pr->throttling);
241 switch (event) {
242 case THROTTLING_PRECHANGE:
243 /*
244 * Prechange event is used to choose one proper t-state,
245 * which meets the limits of thermal, user and _TPC.
246 */
247 p_limit = &pr->limit;
248 if (p_limit->thermal.tx > target_state)
249 target_state = p_limit->thermal.tx;
250 if (p_limit->user.tx > target_state)
251 target_state = p_limit->user.tx;
252 if (pr->throttling_platform_limit > target_state)
253 target_state = pr->throttling_platform_limit;
254 if (target_state >= p_throttling->state_count) {
255 printk(KERN_WARNING
256 "Exceed the limit of T-state \n");
257 target_state = p_throttling->state_count - 1;
258 }
259 p_tstate->target_state = target_state;
260 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
261 "target T-state of CPU %d is T%d\n",
262 cpu, target_state));
263 break;
264 case THROTTLING_POSTCHANGE:
265 /*
266 * Postchange event is only used to update the
267 * T-state flag of acpi_processor_throttling.
268 */
269 p_throttling->state = target_state;
270 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
271 "CPU %d is switched to T%d\n",
272 cpu, target_state));
273 break;
274 default:
275 printk(KERN_WARNING
276 "Unsupported Throttling notifier event\n");
277 break;
278 }
279
280 return 0;
281 }
282
283 /*
284 * _TPC - Throttling Present Capabilities
285 */
286 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
287 {
288 acpi_status status = 0;
289 unsigned long long tpc = 0;
290
291 if (!pr)
292 return -EINVAL;
293
294 if (ignore_tpc)
295 goto end;
296
297 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
298 if (ACPI_FAILURE(status)) {
299 if (status != AE_NOT_FOUND) {
300 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
301 }
302 return -ENODEV;
303 }
304
305 end:
306 pr->throttling_platform_limit = (int)tpc;
307 return 0;
308 }
309
310 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
311 {
312 int result = 0;
313 int throttling_limit;
314 int current_state;
315 struct acpi_processor_limit *limit;
316 int target_state;
317
318 if (ignore_tpc)
319 return 0;
320
321 result = acpi_processor_get_platform_limit(pr);
322 if (result) {
323 /* Throttling Limit is unsupported */
324 return result;
325 }
326
327 throttling_limit = pr->throttling_platform_limit;
328 if (throttling_limit >= pr->throttling.state_count) {
329 /* Uncorrect Throttling Limit */
330 return -EINVAL;
331 }
332
333 current_state = pr->throttling.state;
334 if (current_state > throttling_limit) {
335 /*
336 * The current state can meet the requirement of
337 * _TPC limit. But it is reasonable that OSPM changes
338 * t-states from high to low for better performance.
339 * Of course the limit condition of thermal
340 * and user should be considered.
341 */
342 limit = &pr->limit;
343 target_state = throttling_limit;
344 if (limit->thermal.tx > target_state)
345 target_state = limit->thermal.tx;
346 if (limit->user.tx > target_state)
347 target_state = limit->user.tx;
348 } else if (current_state == throttling_limit) {
349 /*
350 * Unnecessary to change the throttling state
351 */
352 return 0;
353 } else {
354 /*
355 * If the current state is lower than the limit of _TPC, it
356 * will be forced to switch to the throttling state defined
357 * by throttling_platfor_limit.
358 * Because the previous state meets with the limit condition
359 * of thermal and user, it is unnecessary to check it again.
360 */
361 target_state = throttling_limit;
362 }
363 return acpi_processor_set_throttling(pr, target_state, false);
364 }
365
366 /*
367 * This function is used to reevaluate whether the T-state is valid
368 * after one CPU is onlined/offlined.
369 * It is noted that it won't reevaluate the following properties for
370 * the T-state.
371 * 1. Control method.
372 * 2. the number of supported T-state
373 * 3. TSD domain
374 */
375 void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
376 unsigned long action)
377 {
378 int result = 0;
379
380 if (action == CPU_DEAD) {
381 /* When one CPU is offline, the T-state throttling
382 * will be invalidated.
383 */
384 pr->flags.throttling = 0;
385 return;
386 }
387 /* the following is to recheck whether the T-state is valid for
388 * the online CPU
389 */
390 if (!pr->throttling.state_count) {
391 /* If the number of T-state is invalid, it is
392 * invalidated.
393 */
394 pr->flags.throttling = 0;
395 return;
396 }
397 pr->flags.throttling = 1;
398
399 /* Disable throttling (if enabled). We'll let subsequent
400 * policy (e.g.thermal) decide to lower performance if it
401 * so chooses, but for now we'll crank up the speed.
402 */
403
404 result = acpi_processor_get_throttling(pr);
405 if (result)
406 goto end;
407
408 if (pr->throttling.state) {
409 result = acpi_processor_set_throttling(pr, 0, false);
410 if (result)
411 goto end;
412 }
413
414 end:
415 if (result)
416 pr->flags.throttling = 0;
417 }
418 /*
419 * _PTC - Processor Throttling Control (and status) register location
420 */
421 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
422 {
423 int result = 0;
424 acpi_status status = 0;
425 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
426 union acpi_object *ptc = NULL;
427 union acpi_object obj = { 0 };
428 struct acpi_processor_throttling *throttling;
429
430 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
431 if (ACPI_FAILURE(status)) {
432 if (status != AE_NOT_FOUND) {
433 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
434 }
435 return -ENODEV;
436 }
437
438 ptc = (union acpi_object *)buffer.pointer;
439 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
440 || (ptc->package.count != 2)) {
441 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
442 result = -EFAULT;
443 goto end;
444 }
445
446 /*
447 * control_register
448 */
449
450 obj = ptc->package.elements[0];
451
452 if ((obj.type != ACPI_TYPE_BUFFER)
453 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
454 || (obj.buffer.pointer == NULL)) {
455 printk(KERN_ERR PREFIX
456 "Invalid _PTC data (control_register)\n");
457 result = -EFAULT;
458 goto end;
459 }
460 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
461 sizeof(struct acpi_ptc_register));
462
463 /*
464 * status_register
465 */
466
467 obj = ptc->package.elements[1];
468
469 if ((obj.type != ACPI_TYPE_BUFFER)
470 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
471 || (obj.buffer.pointer == NULL)) {
472 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
473 result = -EFAULT;
474 goto end;
475 }
476
477 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
478 sizeof(struct acpi_ptc_register));
479
480 throttling = &pr->throttling;
481
482 if ((throttling->control_register.bit_width +
483 throttling->control_register.bit_offset) > 32) {
484 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
485 result = -EFAULT;
486 goto end;
487 }
488
489 if ((throttling->status_register.bit_width +
490 throttling->status_register.bit_offset) > 32) {
491 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
492 result = -EFAULT;
493 goto end;
494 }
495
496 end:
497 kfree(buffer.pointer);
498
499 return result;
500 }
501
502 /*
503 * _TSS - Throttling Supported States
504 */
505 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
506 {
507 int result = 0;
508 acpi_status status = AE_OK;
509 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
510 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
511 struct acpi_buffer state = { 0, NULL };
512 union acpi_object *tss = NULL;
513 int i;
514
515 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
516 if (ACPI_FAILURE(status)) {
517 if (status != AE_NOT_FOUND) {
518 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
519 }
520 return -ENODEV;
521 }
522
523 tss = buffer.pointer;
524 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
525 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
526 result = -EFAULT;
527 goto end;
528 }
529
530 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
531 tss->package.count));
532
533 pr->throttling.state_count = tss->package.count;
534 pr->throttling.states_tss =
535 kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
536 GFP_KERNEL);
537 if (!pr->throttling.states_tss) {
538 result = -ENOMEM;
539 goto end;
540 }
541
542 for (i = 0; i < pr->throttling.state_count; i++) {
543
544 struct acpi_processor_tx_tss *tx =
545 (struct acpi_processor_tx_tss *)&(pr->throttling.
546 states_tss[i]);
547
548 state.length = sizeof(struct acpi_processor_tx_tss);
549 state.pointer = tx;
550
551 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
552
553 status = acpi_extract_package(&(tss->package.elements[i]),
554 &format, &state);
555 if (ACPI_FAILURE(status)) {
556 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
557 result = -EFAULT;
558 kfree(pr->throttling.states_tss);
559 goto end;
560 }
561
562 if (!tx->freqpercentage) {
563 printk(KERN_ERR PREFIX
564 "Invalid _TSS data: freq is zero\n");
565 result = -EFAULT;
566 kfree(pr->throttling.states_tss);
567 goto end;
568 }
569 }
570
571 end:
572 kfree(buffer.pointer);
573
574 return result;
575 }
576
577 /*
578 * _TSD - T-State Dependencies
579 */
580 static int acpi_processor_get_tsd(struct acpi_processor *pr)
581 {
582 int result = 0;
583 acpi_status status = AE_OK;
584 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
585 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
586 struct acpi_buffer state = { 0, NULL };
587 union acpi_object *tsd = NULL;
588 struct acpi_tsd_package *pdomain;
589 struct acpi_processor_throttling *pthrottling;
590
591 pthrottling = &pr->throttling;
592 pthrottling->tsd_valid_flag = 0;
593
594 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
595 if (ACPI_FAILURE(status)) {
596 if (status != AE_NOT_FOUND) {
597 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
598 }
599 return -ENODEV;
600 }
601
602 tsd = buffer.pointer;
603 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
604 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
605 result = -EFAULT;
606 goto end;
607 }
608
609 if (tsd->package.count != 1) {
610 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
611 result = -EFAULT;
612 goto end;
613 }
614
615 pdomain = &(pr->throttling.domain_info);
616
617 state.length = sizeof(struct acpi_tsd_package);
618 state.pointer = pdomain;
619
620 status = acpi_extract_package(&(tsd->package.elements[0]),
621 &format, &state);
622 if (ACPI_FAILURE(status)) {
623 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
624 result = -EFAULT;
625 goto end;
626 }
627
628 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
629 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
630 result = -EFAULT;
631 goto end;
632 }
633
634 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
635 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
636 result = -EFAULT;
637 goto end;
638 }
639
640 pthrottling = &pr->throttling;
641 pthrottling->tsd_valid_flag = 1;
642 pthrottling->shared_type = pdomain->coord_type;
643 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
644 /*
645 * If the coordination type is not defined in ACPI spec,
646 * the tsd_valid_flag will be clear and coordination type
647 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
648 */
649 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
650 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
651 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
652 pthrottling->tsd_valid_flag = 0;
653 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
654 }
655
656 end:
657 kfree(buffer.pointer);
658 return result;
659 }
660
661 /* --------------------------------------------------------------------------
662 Throttling Control
663 -------------------------------------------------------------------------- */
664 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
665 {
666 int state = 0;
667 u32 value = 0;
668 u32 duty_mask = 0;
669 u32 duty_value = 0;
670
671 if (!pr)
672 return -EINVAL;
673
674 if (!pr->flags.throttling)
675 return -ENODEV;
676
677 pr->throttling.state = 0;
678
679 duty_mask = pr->throttling.state_count - 1;
680
681 duty_mask <<= pr->throttling.duty_offset;
682
683 local_irq_disable();
684
685 value = inl(pr->throttling.address);
686
687 /*
688 * Compute the current throttling state when throttling is enabled
689 * (bit 4 is on).
690 */
691 if (value & 0x10) {
692 duty_value = value & duty_mask;
693 duty_value >>= pr->throttling.duty_offset;
694
695 if (duty_value)
696 state = pr->throttling.state_count - duty_value;
697 }
698
699 pr->throttling.state = state;
700
701 local_irq_enable();
702
703 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
704 "Throttling state is T%d (%d%% throttling applied)\n",
705 state, pr->throttling.states[state].performance));
706
707 return 0;
708 }
709
710 #ifdef CONFIG_X86
711 static int acpi_throttling_rdmsr(u64 *value)
712 {
713 u64 msr_high, msr_low;
714 u64 msr = 0;
715 int ret = -1;
716
717 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
718 !this_cpu_has(X86_FEATURE_ACPI)) {
719 printk(KERN_ERR PREFIX
720 "HARDWARE addr space,NOT supported yet\n");
721 } else {
722 msr_low = 0;
723 msr_high = 0;
724 rdmsr_safe(MSR_IA32_THERM_CONTROL,
725 (u32 *)&msr_low , (u32 *) &msr_high);
726 msr = (msr_high << 32) | msr_low;
727 *value = (u64) msr;
728 ret = 0;
729 }
730 return ret;
731 }
732
733 static int acpi_throttling_wrmsr(u64 value)
734 {
735 int ret = -1;
736 u64 msr;
737
738 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
739 !this_cpu_has(X86_FEATURE_ACPI)) {
740 printk(KERN_ERR PREFIX
741 "HARDWARE addr space,NOT supported yet\n");
742 } else {
743 msr = value;
744 wrmsr_safe(MSR_IA32_THERM_CONTROL,
745 msr & 0xffffffff, msr >> 32);
746 ret = 0;
747 }
748 return ret;
749 }
750 #else
751 static int acpi_throttling_rdmsr(u64 *value)
752 {
753 printk(KERN_ERR PREFIX
754 "HARDWARE addr space,NOT supported yet\n");
755 return -1;
756 }
757
758 static int acpi_throttling_wrmsr(u64 value)
759 {
760 printk(KERN_ERR PREFIX
761 "HARDWARE addr space,NOT supported yet\n");
762 return -1;
763 }
764 #endif
765
766 static int acpi_read_throttling_status(struct acpi_processor *pr,
767 u64 *value)
768 {
769 u32 bit_width, bit_offset;
770 u32 ptc_value;
771 u64 ptc_mask;
772 struct acpi_processor_throttling *throttling;
773 int ret = -1;
774
775 throttling = &pr->throttling;
776 switch (throttling->status_register.space_id) {
777 case ACPI_ADR_SPACE_SYSTEM_IO:
778 bit_width = throttling->status_register.bit_width;
779 bit_offset = throttling->status_register.bit_offset;
780
781 acpi_os_read_port((acpi_io_address) throttling->status_register.
782 address, &ptc_value,
783 (u32) (bit_width + bit_offset));
784 ptc_mask = (1 << bit_width) - 1;
785 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
786 ret = 0;
787 break;
788 case ACPI_ADR_SPACE_FIXED_HARDWARE:
789 ret = acpi_throttling_rdmsr(value);
790 break;
791 default:
792 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
793 (u32) (throttling->status_register.space_id));
794 }
795 return ret;
796 }
797
798 static int acpi_write_throttling_state(struct acpi_processor *pr,
799 u64 value)
800 {
801 u32 bit_width, bit_offset;
802 u64 ptc_value;
803 u64 ptc_mask;
804 struct acpi_processor_throttling *throttling;
805 int ret = -1;
806
807 throttling = &pr->throttling;
808 switch (throttling->control_register.space_id) {
809 case ACPI_ADR_SPACE_SYSTEM_IO:
810 bit_width = throttling->control_register.bit_width;
811 bit_offset = throttling->control_register.bit_offset;
812 ptc_mask = (1 << bit_width) - 1;
813 ptc_value = value & ptc_mask;
814
815 acpi_os_write_port((acpi_io_address) throttling->
816 control_register.address,
817 (u32) (ptc_value << bit_offset),
818 (u32) (bit_width + bit_offset));
819 ret = 0;
820 break;
821 case ACPI_ADR_SPACE_FIXED_HARDWARE:
822 ret = acpi_throttling_wrmsr(value);
823 break;
824 default:
825 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
826 (u32) (throttling->control_register.space_id));
827 }
828 return ret;
829 }
830
831 static int acpi_get_throttling_state(struct acpi_processor *pr,
832 u64 value)
833 {
834 int i;
835
836 for (i = 0; i < pr->throttling.state_count; i++) {
837 struct acpi_processor_tx_tss *tx =
838 (struct acpi_processor_tx_tss *)&(pr->throttling.
839 states_tss[i]);
840 if (tx->control == value)
841 return i;
842 }
843 return -1;
844 }
845
846 static int acpi_get_throttling_value(struct acpi_processor *pr,
847 int state, u64 *value)
848 {
849 int ret = -1;
850
851 if (state >= 0 && state <= pr->throttling.state_count) {
852 struct acpi_processor_tx_tss *tx =
853 (struct acpi_processor_tx_tss *)&(pr->throttling.
854 states_tss[state]);
855 *value = tx->control;
856 ret = 0;
857 }
858 return ret;
859 }
860
861 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
862 {
863 int state = 0;
864 int ret;
865 u64 value;
866
867 if (!pr)
868 return -EINVAL;
869
870 if (!pr->flags.throttling)
871 return -ENODEV;
872
873 pr->throttling.state = 0;
874
875 value = 0;
876 ret = acpi_read_throttling_status(pr, &value);
877 if (ret >= 0) {
878 state = acpi_get_throttling_state(pr, value);
879 if (state == -1) {
880 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
881 "Invalid throttling state, reset\n"));
882 state = 0;
883 ret = acpi_processor_set_throttling(pr, state, true);
884 if (ret)
885 return ret;
886 }
887 pr->throttling.state = state;
888 }
889
890 return 0;
891 }
892
893 static int acpi_processor_get_throttling(struct acpi_processor *pr)
894 {
895 cpumask_var_t saved_mask;
896 int ret;
897
898 if (!pr)
899 return -EINVAL;
900
901 if (!pr->flags.throttling)
902 return -ENODEV;
903
904 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
905 return -ENOMEM;
906
907 /*
908 * Migrate task to the cpu pointed by pr.
909 */
910 cpumask_copy(saved_mask, &current->cpus_allowed);
911 /* FIXME: use work_on_cpu() */
912 if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) {
913 /* Can't migrate to the target pr->id CPU. Exit */
914 free_cpumask_var(saved_mask);
915 return -ENODEV;
916 }
917 ret = pr->throttling.acpi_processor_get_throttling(pr);
918 /* restore the previous state */
919 set_cpus_allowed_ptr(current, saved_mask);
920 free_cpumask_var(saved_mask);
921
922 return ret;
923 }
924
925 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
926 {
927 int i, step;
928
929 if (!pr->throttling.address) {
930 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
931 return -EINVAL;
932 } else if (!pr->throttling.duty_width) {
933 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
934 return -EINVAL;
935 }
936 /* TBD: Support duty_cycle values that span bit 4. */
937 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
938 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
939 return -EINVAL;
940 }
941
942 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
943
944 /*
945 * Compute state values. Note that throttling displays a linear power
946 * performance relationship (at 50% performance the CPU will consume
947 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
948 */
949
950 step = (1000 / pr->throttling.state_count);
951
952 for (i = 0; i < pr->throttling.state_count; i++) {
953 pr->throttling.states[i].performance = 1000 - step * i;
954 pr->throttling.states[i].power = 1000 - step * i;
955 }
956 return 0;
957 }
958
959 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
960 int state, bool force)
961 {
962 u32 value = 0;
963 u32 duty_mask = 0;
964 u32 duty_value = 0;
965
966 if (!pr)
967 return -EINVAL;
968
969 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
970 return -EINVAL;
971
972 if (!pr->flags.throttling)
973 return -ENODEV;
974
975 if (!force && (state == pr->throttling.state))
976 return 0;
977
978 if (state < pr->throttling_platform_limit)
979 return -EPERM;
980 /*
981 * Calculate the duty_value and duty_mask.
982 */
983 if (state) {
984 duty_value = pr->throttling.state_count - state;
985
986 duty_value <<= pr->throttling.duty_offset;
987
988 /* Used to clear all duty_value bits */
989 duty_mask = pr->throttling.state_count - 1;
990
991 duty_mask <<= acpi_gbl_FADT.duty_offset;
992 duty_mask = ~duty_mask;
993 }
994
995 local_irq_disable();
996
997 /*
998 * Disable throttling by writing a 0 to bit 4. Note that we must
999 * turn it off before you can change the duty_value.
1000 */
1001 value = inl(pr->throttling.address);
1002 if (value & 0x10) {
1003 value &= 0xFFFFFFEF;
1004 outl(value, pr->throttling.address);
1005 }
1006
1007 /*
1008 * Write the new duty_value and then enable throttling. Note
1009 * that a state value of 0 leaves throttling disabled.
1010 */
1011 if (state) {
1012 value &= duty_mask;
1013 value |= duty_value;
1014 outl(value, pr->throttling.address);
1015
1016 value |= 0x00000010;
1017 outl(value, pr->throttling.address);
1018 }
1019
1020 pr->throttling.state = state;
1021
1022 local_irq_enable();
1023
1024 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1025 "Throttling state set to T%d (%d%%)\n", state,
1026 (pr->throttling.states[state].performance ? pr->
1027 throttling.states[state].performance / 10 : 0)));
1028
1029 return 0;
1030 }
1031
1032 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1033 int state, bool force)
1034 {
1035 int ret;
1036 u64 value;
1037
1038 if (!pr)
1039 return -EINVAL;
1040
1041 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1042 return -EINVAL;
1043
1044 if (!pr->flags.throttling)
1045 return -ENODEV;
1046
1047 if (!force && (state == pr->throttling.state))
1048 return 0;
1049
1050 if (state < pr->throttling_platform_limit)
1051 return -EPERM;
1052
1053 value = 0;
1054 ret = acpi_get_throttling_value(pr, state, &value);
1055 if (ret >= 0) {
1056 acpi_write_throttling_state(pr, value);
1057 pr->throttling.state = state;
1058 }
1059
1060 return 0;
1061 }
1062
1063 int acpi_processor_set_throttling(struct acpi_processor *pr,
1064 int state, bool force)
1065 {
1066 cpumask_var_t saved_mask;
1067 int ret = 0;
1068 unsigned int i;
1069 struct acpi_processor *match_pr;
1070 struct acpi_processor_throttling *p_throttling;
1071 struct throttling_tstate t_state;
1072 cpumask_var_t online_throttling_cpus;
1073
1074 if (!pr)
1075 return -EINVAL;
1076
1077 if (!pr->flags.throttling)
1078 return -ENODEV;
1079
1080 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1081 return -EINVAL;
1082
1083 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1084 return -ENOMEM;
1085
1086 if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1087 free_cpumask_var(saved_mask);
1088 return -ENOMEM;
1089 }
1090
1091 if (cpu_is_offline(pr->id)) {
1092 /*
1093 * the cpu pointed by pr->id is offline. Unnecessary to change
1094 * the throttling state any more.
1095 */
1096 return -ENODEV;
1097 }
1098
1099 cpumask_copy(saved_mask, &current->cpus_allowed);
1100 t_state.target_state = state;
1101 p_throttling = &(pr->throttling);
1102 cpumask_and(online_throttling_cpus, cpu_online_mask,
1103 p_throttling->shared_cpu_map);
1104 /*
1105 * The throttling notifier will be called for every
1106 * affected cpu in order to get one proper T-state.
1107 * The notifier event is THROTTLING_PRECHANGE.
1108 */
1109 for_each_cpu(i, online_throttling_cpus) {
1110 t_state.cpu = i;
1111 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1112 &t_state);
1113 }
1114 /*
1115 * The function of acpi_processor_set_throttling will be called
1116 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1117 * it is necessary to call it for every affected cpu. Otherwise
1118 * it can be called only for the cpu pointed by pr.
1119 */
1120 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1121 /* FIXME: use work_on_cpu() */
1122 if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) {
1123 /* Can't migrate to the pr->id CPU. Exit */
1124 ret = -ENODEV;
1125 goto exit;
1126 }
1127 ret = p_throttling->acpi_processor_set_throttling(pr,
1128 t_state.target_state, force);
1129 } else {
1130 /*
1131 * When the T-state coordination is SW_ALL or HW_ALL,
1132 * it is necessary to set T-state for every affected
1133 * cpus.
1134 */
1135 for_each_cpu(i, online_throttling_cpus) {
1136 match_pr = per_cpu(processors, i);
1137 /*
1138 * If the pointer is invalid, we will report the
1139 * error message and continue.
1140 */
1141 if (!match_pr) {
1142 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1143 "Invalid Pointer for CPU %d\n", i));
1144 continue;
1145 }
1146 /*
1147 * If the throttling control is unsupported on CPU i,
1148 * we will report the error message and continue.
1149 */
1150 if (!match_pr->flags.throttling) {
1151 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1152 "Throttling Control is unsupported "
1153 "on CPU %d\n", i));
1154 continue;
1155 }
1156 t_state.cpu = i;
1157 /* FIXME: use work_on_cpu() */
1158 if (set_cpus_allowed_ptr(current, cpumask_of(i)))
1159 continue;
1160 ret = match_pr->throttling.
1161 acpi_processor_set_throttling(
1162 match_pr, t_state.target_state, force);
1163 }
1164 }
1165 /*
1166 * After the set_throttling is called, the
1167 * throttling notifier is called for every
1168 * affected cpu to update the T-states.
1169 * The notifier event is THROTTLING_POSTCHANGE
1170 */
1171 for_each_cpu(i, online_throttling_cpus) {
1172 t_state.cpu = i;
1173 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1174 &t_state);
1175 }
1176 /* restore the previous state */
1177 /* FIXME: use work_on_cpu() */
1178 set_cpus_allowed_ptr(current, saved_mask);
1179 exit:
1180 free_cpumask_var(online_throttling_cpus);
1181 free_cpumask_var(saved_mask);
1182 return ret;
1183 }
1184
1185 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1186 {
1187 int result = 0;
1188 struct acpi_processor_throttling *pthrottling;
1189
1190 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1191 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1192 pr->throttling.address,
1193 pr->throttling.duty_offset,
1194 pr->throttling.duty_width));
1195
1196 /*
1197 * Evaluate _PTC, _TSS and _TPC
1198 * They must all be present or none of them can be used.
1199 */
1200 if (acpi_processor_get_throttling_control(pr) ||
1201 acpi_processor_get_throttling_states(pr) ||
1202 acpi_processor_get_platform_limit(pr))
1203 {
1204 pr->throttling.acpi_processor_get_throttling =
1205 &acpi_processor_get_throttling_fadt;
1206 pr->throttling.acpi_processor_set_throttling =
1207 &acpi_processor_set_throttling_fadt;
1208 if (acpi_processor_get_fadt_info(pr))
1209 return 0;
1210 } else {
1211 pr->throttling.acpi_processor_get_throttling =
1212 &acpi_processor_get_throttling_ptc;
1213 pr->throttling.acpi_processor_set_throttling =
1214 &acpi_processor_set_throttling_ptc;
1215 }
1216
1217 /*
1218 * If TSD package for one CPU can't be parsed successfully, it means
1219 * that this CPU will have no coordination with other CPUs.
1220 */
1221 if (acpi_processor_get_tsd(pr)) {
1222 pthrottling = &pr->throttling;
1223 pthrottling->tsd_valid_flag = 0;
1224 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1225 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1226 }
1227
1228 /*
1229 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1230 * This shouldn't be an issue as few (if any) mobile systems ever
1231 * used this part.
1232 */
1233 if (errata.piix4.throttle) {
1234 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1235 "Throttling not supported on PIIX4 A- or B-step\n"));
1236 return 0;
1237 }
1238
1239 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1240 pr->throttling.state_count));
1241
1242 pr->flags.throttling = 1;
1243
1244 /*
1245 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1246 * thermal) decide to lower performance if it so chooses, but for now
1247 * we'll crank up the speed.
1248 */
1249
1250 result = acpi_processor_get_throttling(pr);
1251 if (result)
1252 goto end;
1253
1254 if (pr->throttling.state) {
1255 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1256 "Disabling throttling (was T%d)\n",
1257 pr->throttling.state));
1258 result = acpi_processor_set_throttling(pr, 0, false);
1259 if (result)
1260 goto end;
1261 }
1262
1263 end:
1264 if (result)
1265 pr->flags.throttling = 0;
1266
1267 return result;
1268 }
1269
Linux with added FPC-III support