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Merge branch 'x86/cleanups'
[linux-2.6/x86.git] / drivers / acpi / processor_throttling.c
blob605a2954ef175e563db7d212d2184c924b7b5013
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
36 #include <asm/io.h>
37 #include <asm/uaccess.h>
38
39 #include <acpi/acpi_bus.h>
40 #include <acpi/acpi_drivers.h>
41 #include <acpi/processor.h>
42
43 #define PREFIX "ACPI: "
44
45 #define ACPI_PROCESSOR_CLASS "processor"
46 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
47 ACPI_MODULE_NAME("processor_throttling");
48
49 /* ignore_tpc:
50 * 0 -> acpi processor driver doesn't ignore _TPC values
51 * 1 -> acpi processor driver ignores _TPC values
52 */
53 static int ignore_tpc;
54 module_param(ignore_tpc, int, 0644);
55 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
56
57 struct throttling_tstate {
58 unsigned int cpu; /* cpu nr */
59 int target_state; /* target T-state */
60 };
61
62 #define THROTTLING_PRECHANGE (1)
63 #define THROTTLING_POSTCHANGE (2)
64
65 static int acpi_processor_get_throttling(struct acpi_processor *pr);
66 int acpi_processor_set_throttling(struct acpi_processor *pr,
67 int state, bool force);
68
69 static int acpi_processor_update_tsd_coord(void)
70 {
71 int count, count_target;
72 int retval = 0;
73 unsigned int i, j;
74 cpumask_var_t covered_cpus;
75 struct acpi_processor *pr, *match_pr;
76 struct acpi_tsd_package *pdomain, *match_pdomain;
77 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
78
79 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
80 return -ENOMEM;
81
82 /*
83 * Now that we have _TSD data from all CPUs, lets setup T-state
84 * coordination between all CPUs.
85 */
86 for_each_possible_cpu(i) {
87 pr = per_cpu(processors, i);
88 if (!pr)
89 continue;
90
91 /* Basic validity check for domain info */
92 pthrottling = &(pr->throttling);
93
94 /*
95 * If tsd package for one cpu is invalid, the coordination
96 * among all CPUs is thought as invalid.
97 * Maybe it is ugly.
98 */
99 if (!pthrottling->tsd_valid_flag) {
100 retval = -EINVAL;
101 break;
102 }
103 }
104 if (retval)
105 goto err_ret;
106
107 for_each_possible_cpu(i) {
108 pr = per_cpu(processors, i);
109 if (!pr)
110 continue;
111
112 if (cpumask_test_cpu(i, covered_cpus))
113 continue;
114 pthrottling = &pr->throttling;
115
116 pdomain = &(pthrottling->domain_info);
117 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
118 cpumask_set_cpu(i, covered_cpus);
119 /*
120 * If the number of processor in the TSD domain is 1, it is
121 * unnecessary to parse the coordination for this CPU.
122 */
123 if (pdomain->num_processors <= 1)
124 continue;
125
126 /* Validate the Domain info */
127 count_target = pdomain->num_processors;
128 count = 1;
129
130 for_each_possible_cpu(j) {
131 if (i == j)
132 continue;
133
134 match_pr = per_cpu(processors, j);
135 if (!match_pr)
136 continue;
137
138 match_pthrottling = &(match_pr->throttling);
139 match_pdomain = &(match_pthrottling->domain_info);
140 if (match_pdomain->domain != pdomain->domain)
141 continue;
142
143 /* Here i and j are in the same domain.
144 * If two TSD packages have the same domain, they
145 * should have the same num_porcessors and
146 * coordination type. Otherwise it will be regarded
147 * as illegal.
148 */
149 if (match_pdomain->num_processors != count_target) {
150 retval = -EINVAL;
151 goto err_ret;
152 }
153
154 if (pdomain->coord_type != match_pdomain->coord_type) {
155 retval = -EINVAL;
156 goto err_ret;
157 }
158
159 cpumask_set_cpu(j, covered_cpus);
160 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
161 count++;
162 }
163 for_each_possible_cpu(j) {
164 if (i == j)
165 continue;
166
167 match_pr = per_cpu(processors, j);
168 if (!match_pr)
169 continue;
170
171 match_pthrottling = &(match_pr->throttling);
172 match_pdomain = &(match_pthrottling->domain_info);
173 if (match_pdomain->domain != pdomain->domain)
174 continue;
175
176 /*
177 * If some CPUS have the same domain, they
178 * will have the same shared_cpu_map.
179 */
180 cpumask_copy(match_pthrottling->shared_cpu_map,
181 pthrottling->shared_cpu_map);
182 }
183 }
184
185 err_ret:
186 free_cpumask_var(covered_cpus);
187
188 for_each_possible_cpu(i) {
189 pr = per_cpu(processors, i);
190 if (!pr)
191 continue;
192
193 /*
194 * Assume no coordination on any error parsing domain info.
195 * The coordination type will be forced as SW_ALL.
196 */
197 if (retval) {
198 pthrottling = &(pr->throttling);
199 cpumask_clear(pthrottling->shared_cpu_map);
200 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
201 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
202 }
203 }
204
205 return retval;
206 }
207
208 /*
209 * Update the T-state coordination after the _TSD
210 * data for all cpus is obtained.
211 */
212 void acpi_processor_throttling_init(void)
213 {
214 if (acpi_processor_update_tsd_coord())
215 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
216 "Assume no T-state coordination\n"));
217
218 return;
219 }
220
221 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
222 {
223 struct throttling_tstate *p_tstate = data;
224 struct acpi_processor *pr;
225 unsigned int cpu ;
226 int target_state;
227 struct acpi_processor_limit *p_limit;
228 struct acpi_processor_throttling *p_throttling;
229
230 cpu = p_tstate->cpu;
231 pr = per_cpu(processors, cpu);
232 if (!pr) {
233 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
234 return 0;
235 }
236 if (!pr->flags.throttling) {
237 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
238 "unsupported on CPU %d\n", cpu));
239 return 0;
240 }
241 target_state = p_tstate->target_state;
242 p_throttling = &(pr->throttling);
243 switch (event) {
244 case THROTTLING_PRECHANGE:
245 /*
246 * Prechange event is used to choose one proper t-state,
247 * which meets the limits of thermal, user and _TPC.
248 */
249 p_limit = &pr->limit;
250 if (p_limit->thermal.tx > target_state)
251 target_state = p_limit->thermal.tx;
252 if (p_limit->user.tx > target_state)
253 target_state = p_limit->user.tx;
254 if (pr->throttling_platform_limit > target_state)
255 target_state = pr->throttling_platform_limit;
256 if (target_state >= p_throttling->state_count) {
257 printk(KERN_WARNING
258 "Exceed the limit of T-state \n");
259 target_state = p_throttling->state_count - 1;
260 }
261 p_tstate->target_state = target_state;
262 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
263 "target T-state of CPU %d is T%d\n",
264 cpu, target_state));
265 break;
266 case THROTTLING_POSTCHANGE:
267 /*
268 * Postchange event is only used to update the
269 * T-state flag of acpi_processor_throttling.
270 */
271 p_throttling->state = target_state;
272 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
273 "CPU %d is switched to T%d\n",
274 cpu, target_state));
275 break;
276 default:
277 printk(KERN_WARNING
278 "Unsupported Throttling notifier event\n");
279 break;
280 }
281
282 return 0;
283 }
284
285 /*
286 * _TPC - Throttling Present Capabilities
287 */
288 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
289 {
290 acpi_status status = 0;
291 unsigned long long tpc = 0;
292
293 if (!pr)
294 return -EINVAL;
295
296 if (ignore_tpc)
297 goto end;
298
299 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
300 if (ACPI_FAILURE(status)) {
301 if (status != AE_NOT_FOUND) {
302 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
303 }
304 return -ENODEV;
305 }
306
307 end:
308 pr->throttling_platform_limit = (int)tpc;
309 return 0;
310 }
311
312 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
313 {
314 int result = 0;
315 int throttling_limit;
316 int current_state;
317 struct acpi_processor_limit *limit;
318 int target_state;
319
320 if (ignore_tpc)
321 return 0;
322
323 result = acpi_processor_get_platform_limit(pr);
324 if (result) {
325 /* Throttling Limit is unsupported */
326 return result;
327 }
328
329 throttling_limit = pr->throttling_platform_limit;
330 if (throttling_limit >= pr->throttling.state_count) {
331 /* Uncorrect Throttling Limit */
332 return -EINVAL;
333 }
334
335 current_state = pr->throttling.state;
336 if (current_state > throttling_limit) {
337 /*
338 * The current state can meet the requirement of
339 * _TPC limit. But it is reasonable that OSPM changes
340 * t-states from high to low for better performance.
341 * Of course the limit condition of thermal
342 * and user should be considered.
343 */
344 limit = &pr->limit;
345 target_state = throttling_limit;
346 if (limit->thermal.tx > target_state)
347 target_state = limit->thermal.tx;
348 if (limit->user.tx > target_state)
349 target_state = limit->user.tx;
350 } else if (current_state == throttling_limit) {
351 /*
352 * Unnecessary to change the throttling state
353 */
354 return 0;
355 } else {
356 /*
357 * If the current state is lower than the limit of _TPC, it
358 * will be forced to switch to the throttling state defined
359 * by throttling_platfor_limit.
360 * Because the previous state meets with the limit condition
361 * of thermal and user, it is unnecessary to check it again.
362 */
363 target_state = throttling_limit;
364 }
365 return acpi_processor_set_throttling(pr, target_state, false);
366 }
367
368 /*
369 * This function is used to reevaluate whether the T-state is valid
370 * after one CPU is onlined/offlined.
371 * It is noted that it won't reevaluate the following properties for
372 * the T-state.
373 * 1. Control method.
374 * 2. the number of supported T-state
375 * 3. TSD domain
376 */
377 void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
378 unsigned long action)
379 {
380 int result = 0;
381
382 if (action == CPU_DEAD) {
383 /* When one CPU is offline, the T-state throttling
384 * will be invalidated.
385 */
386 pr->flags.throttling = 0;
387 return;
388 }
389 /* the following is to recheck whether the T-state is valid for
390 * the online CPU
391 */
392 if (!pr->throttling.state_count) {
393 /* If the number of T-state is invalid, it is
394 * invalidated.
395 */
396 pr->flags.throttling = 0;
397 return;
398 }
399 pr->flags.throttling = 1;
400
401 /* Disable throttling (if enabled). We'll let subsequent
402 * policy (e.g.thermal) decide to lower performance if it
403 * so chooses, but for now we'll crank up the speed.
404 */
405
406 result = acpi_processor_get_throttling(pr);
407 if (result)
408 goto end;
409
410 if (pr->throttling.state) {
411 result = acpi_processor_set_throttling(pr, 0, false);
412 if (result)
413 goto end;
414 }
415
416 end:
417 if (result)
418 pr->flags.throttling = 0;
419 }
420 /*
421 * _PTC - Processor Throttling Control (and status) register location
422 */
423 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
424 {
425 int result = 0;
426 acpi_status status = 0;
427 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
428 union acpi_object *ptc = NULL;
429 union acpi_object obj = { 0 };
430 struct acpi_processor_throttling *throttling;
431
432 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
433 if (ACPI_FAILURE(status)) {
434 if (status != AE_NOT_FOUND) {
435 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
436 }
437 return -ENODEV;
438 }
439
440 ptc = (union acpi_object *)buffer.pointer;
441 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
442 || (ptc->package.count != 2)) {
443 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
444 result = -EFAULT;
445 goto end;
446 }
447
448 /*
449 * control_register
450 */
451
452 obj = ptc->package.elements[0];
453
454 if ((obj.type != ACPI_TYPE_BUFFER)
455 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
456 || (obj.buffer.pointer == NULL)) {
457 printk(KERN_ERR PREFIX
458 "Invalid _PTC data (control_register)\n");
459 result = -EFAULT;
460 goto end;
461 }
462 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
463 sizeof(struct acpi_ptc_register));
464
465 /*
466 * status_register
467 */
468
469 obj = ptc->package.elements[1];
470
471 if ((obj.type != ACPI_TYPE_BUFFER)
472 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
473 || (obj.buffer.pointer == NULL)) {
474 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
475 result = -EFAULT;
476 goto end;
477 }
478
479 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
480 sizeof(struct acpi_ptc_register));
481
482 throttling = &pr->throttling;
483
484 if ((throttling->control_register.bit_width +
485 throttling->control_register.bit_offset) > 32) {
486 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
487 result = -EFAULT;
488 goto end;
489 }
490
491 if ((throttling->status_register.bit_width +
492 throttling->status_register.bit_offset) > 32) {
493 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
494 result = -EFAULT;
495 goto end;
496 }
497
498 end:
499 kfree(buffer.pointer);
500
501 return result;
502 }
503
504 /*
505 * _TSS - Throttling Supported States
506 */
507 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
508 {
509 int result = 0;
510 acpi_status status = AE_OK;
511 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
512 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
513 struct acpi_buffer state = { 0, NULL };
514 union acpi_object *tss = NULL;
515 int i;
516
517 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
518 if (ACPI_FAILURE(status)) {
519 if (status != AE_NOT_FOUND) {
520 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
521 }
522 return -ENODEV;
523 }
524
525 tss = buffer.pointer;
526 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
527 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
528 result = -EFAULT;
529 goto end;
530 }
531
532 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
533 tss->package.count));
534
535 pr->throttling.state_count = tss->package.count;
536 pr->throttling.states_tss =
537 kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
538 GFP_KERNEL);
539 if (!pr->throttling.states_tss) {
540 result = -ENOMEM;
541 goto end;
542 }
543
544 for (i = 0; i < pr->throttling.state_count; i++) {
545
546 struct acpi_processor_tx_tss *tx =
547 (struct acpi_processor_tx_tss *)&(pr->throttling.
548 states_tss[i]);
549
550 state.length = sizeof(struct acpi_processor_tx_tss);
551 state.pointer = tx;
552
553 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
554
555 status = acpi_extract_package(&(tss->package.elements[i]),
556 &format, &state);
557 if (ACPI_FAILURE(status)) {
558 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
559 result = -EFAULT;
560 kfree(pr->throttling.states_tss);
561 goto end;
562 }
563
564 if (!tx->freqpercentage) {
565 printk(KERN_ERR PREFIX
566 "Invalid _TSS data: freq is zero\n");
567 result = -EFAULT;
568 kfree(pr->throttling.states_tss);
569 goto end;
570 }
571 }
572
573 end:
574 kfree(buffer.pointer);
575
576 return result;
577 }
578
579 /*
580 * _TSD - T-State Dependencies
581 */
582 static int acpi_processor_get_tsd(struct acpi_processor *pr)
583 {
584 int result = 0;
585 acpi_status status = AE_OK;
586 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
587 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
588 struct acpi_buffer state = { 0, NULL };
589 union acpi_object *tsd = NULL;
590 struct acpi_tsd_package *pdomain;
591 struct acpi_processor_throttling *pthrottling;
592
593 pthrottling = &pr->throttling;
594 pthrottling->tsd_valid_flag = 0;
595
596 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
597 if (ACPI_FAILURE(status)) {
598 if (status != AE_NOT_FOUND) {
599 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
600 }
601 return -ENODEV;
602 }
603
604 tsd = buffer.pointer;
605 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
606 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
607 result = -EFAULT;
608 goto end;
609 }
610
611 if (tsd->package.count != 1) {
612 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
613 result = -EFAULT;
614 goto end;
615 }
616
617 pdomain = &(pr->throttling.domain_info);
618
619 state.length = sizeof(struct acpi_tsd_package);
620 state.pointer = pdomain;
621
622 status = acpi_extract_package(&(tsd->package.elements[0]),
623 &format, &state);
624 if (ACPI_FAILURE(status)) {
625 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
626 result = -EFAULT;
627 goto end;
628 }
629
630 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
631 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
632 result = -EFAULT;
633 goto end;
634 }
635
636 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
637 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
638 result = -EFAULT;
639 goto end;
640 }
641
642 pthrottling = &pr->throttling;
643 pthrottling->tsd_valid_flag = 1;
644 pthrottling->shared_type = pdomain->coord_type;
645 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
646 /*
647 * If the coordination type is not defined in ACPI spec,
648 * the tsd_valid_flag will be clear and coordination type
649 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
650 */
651 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
652 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
653 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
654 pthrottling->tsd_valid_flag = 0;
655 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
656 }
657
658 end:
659 kfree(buffer.pointer);
660 return result;
661 }
662
663 /* --------------------------------------------------------------------------
664 Throttling Control
665 -------------------------------------------------------------------------- */
666 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
667 {
668 int state = 0;
669 u32 value = 0;
670 u32 duty_mask = 0;
671 u32 duty_value = 0;
672
673 if (!pr)
674 return -EINVAL;
675
676 if (!pr->flags.throttling)
677 return -ENODEV;
678
679 pr->throttling.state = 0;
680
681 duty_mask = pr->throttling.state_count - 1;
682
683 duty_mask <<= pr->throttling.duty_offset;
684
685 local_irq_disable();
686
687 value = inl(pr->throttling.address);
688
689 /*
690 * Compute the current throttling state when throttling is enabled
691 * (bit 4 is on).
692 */
693 if (value & 0x10) {
694 duty_value = value & duty_mask;
695 duty_value >>= pr->throttling.duty_offset;
696
697 if (duty_value)
698 state = pr->throttling.state_count - duty_value;
699 }
700
701 pr->throttling.state = state;
702
703 local_irq_enable();
704
705 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
706 "Throttling state is T%d (%d%% throttling applied)\n",
707 state, pr->throttling.states[state].performance));
708
709 return 0;
710 }
711
712 #ifdef CONFIG_X86
713 static int acpi_throttling_rdmsr(u64 *value)
714 {
715 u64 msr_high, msr_low;
716 u64 msr = 0;
717 int ret = -1;
718
719 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
720 !this_cpu_has(X86_FEATURE_ACPI)) {
721 printk(KERN_ERR PREFIX
722 "HARDWARE addr space,NOT supported yet\n");
723 } else {
724 msr_low = 0;
725 msr_high = 0;
726 rdmsr_safe(MSR_IA32_THERM_CONTROL,
727 (u32 *)&msr_low , (u32 *) &msr_high);
728 msr = (msr_high << 32) | msr_low;
729 *value = (u64) msr;
730 ret = 0;
731 }
732 return ret;
733 }
734
735 static int acpi_throttling_wrmsr(u64 value)
736 {
737 int ret = -1;
738 u64 msr;
739
740 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
741 !this_cpu_has(X86_FEATURE_ACPI)) {
742 printk(KERN_ERR PREFIX
743 "HARDWARE addr space,NOT supported yet\n");
744 } else {
745 msr = value;
746 wrmsr_safe(MSR_IA32_THERM_CONTROL,
747 msr & 0xffffffff, msr >> 32);
748 ret = 0;
749 }
750 return ret;
751 }
752 #else
753 static int acpi_throttling_rdmsr(u64 *value)
754 {
755 printk(KERN_ERR PREFIX
756 "HARDWARE addr space,NOT supported yet\n");
757 return -1;
758 }
759
760 static int acpi_throttling_wrmsr(u64 value)
761 {
762 printk(KERN_ERR PREFIX
763 "HARDWARE addr space,NOT supported yet\n");
764 return -1;
765 }
766 #endif
767
768 static int acpi_read_throttling_status(struct acpi_processor *pr,
769 u64 *value)
770 {
771 u32 bit_width, bit_offset;
772 u64 ptc_value;
773 u64 ptc_mask;
774 struct acpi_processor_throttling *throttling;
775 int ret = -1;
776
777 throttling = &pr->throttling;
778 switch (throttling->status_register.space_id) {
779 case ACPI_ADR_SPACE_SYSTEM_IO:
780 ptc_value = 0;
781 bit_width = throttling->status_register.bit_width;
782 bit_offset = throttling->status_register.bit_offset;
783
784 acpi_os_read_port((acpi_io_address) throttling->status_register.
785 address, (u32 *) &ptc_value,
786 (u32) (bit_width + bit_offset));
787 ptc_mask = (1 << bit_width) - 1;
788 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
789 ret = 0;
790 break;
791 case ACPI_ADR_SPACE_FIXED_HARDWARE:
792 ret = acpi_throttling_rdmsr(value);
793 break;
794 default:
795 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
796 (u32) (throttling->status_register.space_id));
797 }
798 return ret;
799 }
800
801 static int acpi_write_throttling_state(struct acpi_processor *pr,
802 u64 value)
803 {
804 u32 bit_width, bit_offset;
805 u64 ptc_value;
806 u64 ptc_mask;
807 struct acpi_processor_throttling *throttling;
808 int ret = -1;
809
810 throttling = &pr->throttling;
811 switch (throttling->control_register.space_id) {
812 case ACPI_ADR_SPACE_SYSTEM_IO:
813 bit_width = throttling->control_register.bit_width;
814 bit_offset = throttling->control_register.bit_offset;
815 ptc_mask = (1 << bit_width) - 1;
816 ptc_value = value & ptc_mask;
817
818 acpi_os_write_port((acpi_io_address) throttling->
819 control_register.address,
820 (u32) (ptc_value << bit_offset),
821 (u32) (bit_width + bit_offset));
822 ret = 0;
823 break;
824 case ACPI_ADR_SPACE_FIXED_HARDWARE:
825 ret = acpi_throttling_wrmsr(value);
826 break;
827 default:
828 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
829 (u32) (throttling->control_register.space_id));
830 }
831 return ret;
832 }
833
834 static int acpi_get_throttling_state(struct acpi_processor *pr,
835 u64 value)
836 {
837 int i;
838
839 for (i = 0; i < pr->throttling.state_count; i++) {
840 struct acpi_processor_tx_tss *tx =
841 (struct acpi_processor_tx_tss *)&(pr->throttling.
842 states_tss[i]);
843 if (tx->control == value)
844 return i;
845 }
846 return -1;
847 }
848
849 static int acpi_get_throttling_value(struct acpi_processor *pr,
850 int state, u64 *value)
851 {
852 int ret = -1;
853
854 if (state >= 0 && state <= pr->throttling.state_count) {
855 struct acpi_processor_tx_tss *tx =
856 (struct acpi_processor_tx_tss *)&(pr->throttling.
857 states_tss[state]);
858 *value = tx->control;
859 ret = 0;
860 }
861 return ret;
862 }
863
864 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
865 {
866 int state = 0;
867 int ret;
868 u64 value;
869
870 if (!pr)
871 return -EINVAL;
872
873 if (!pr->flags.throttling)
874 return -ENODEV;
875
876 pr->throttling.state = 0;
877
878 value = 0;
879 ret = acpi_read_throttling_status(pr, &value);
880 if (ret >= 0) {
881 state = acpi_get_throttling_state(pr, value);
882 if (state == -1) {
883 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
884 "Invalid throttling state, reset\n"));
885 state = 0;
886 ret = acpi_processor_set_throttling(pr, state, true);
887 if (ret)
888 return ret;
889 }
890 pr->throttling.state = state;
891 }
892
893 return 0;
894 }
895
896 static int acpi_processor_get_throttling(struct acpi_processor *pr)
897 {
898 cpumask_var_t saved_mask;
899 int ret;
900
901 if (!pr)
902 return -EINVAL;
903
904 if (!pr->flags.throttling)
905 return -ENODEV;
906
907 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
908 return -ENOMEM;
909
910 /*
911 * Migrate task to the cpu pointed by pr.
912 */
913 cpumask_copy(saved_mask, &current->cpus_allowed);
914 /* FIXME: use work_on_cpu() */
915 if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) {
916 /* Can't migrate to the target pr->id CPU. Exit */
917 free_cpumask_var(saved_mask);
918 return -ENODEV;
919 }
920 ret = pr->throttling.acpi_processor_get_throttling(pr);
921 /* restore the previous state */
922 set_cpus_allowed_ptr(current, saved_mask);
923 free_cpumask_var(saved_mask);
924
925 return ret;
926 }
927
928 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
929 {
930 int i, step;
931
932 if (!pr->throttling.address) {
933 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
934 return -EINVAL;
935 } else if (!pr->throttling.duty_width) {
936 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
937 return -EINVAL;
938 }
939 /* TBD: Support duty_cycle values that span bit 4. */
940 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
941 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
942 return -EINVAL;
943 }
944
945 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
946
947 /*
948 * Compute state values. Note that throttling displays a linear power
949 * performance relationship (at 50% performance the CPU will consume
950 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
951 */
952
953 step = (1000 / pr->throttling.state_count);
954
955 for (i = 0; i < pr->throttling.state_count; i++) {
956 pr->throttling.states[i].performance = 1000 - step * i;
957 pr->throttling.states[i].power = 1000 - step * i;
958 }
959 return 0;
960 }
961
962 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
963 int state, bool force)
964 {
965 u32 value = 0;
966 u32 duty_mask = 0;
967 u32 duty_value = 0;
968
969 if (!pr)
970 return -EINVAL;
971
972 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
973 return -EINVAL;
974
975 if (!pr->flags.throttling)
976 return -ENODEV;
977
978 if (!force && (state == pr->throttling.state))
979 return 0;
980
981 if (state < pr->throttling_platform_limit)
982 return -EPERM;
983 /*
984 * Calculate the duty_value and duty_mask.
985 */
986 if (state) {
987 duty_value = pr->throttling.state_count - state;
988
989 duty_value <<= pr->throttling.duty_offset;
990
991 /* Used to clear all duty_value bits */
992 duty_mask = pr->throttling.state_count - 1;
993
994 duty_mask <<= acpi_gbl_FADT.duty_offset;
995 duty_mask = ~duty_mask;
996 }
997
998 local_irq_disable();
999
1000 /*
1001 * Disable throttling by writing a 0 to bit 4. Note that we must
1002 * turn it off before you can change the duty_value.
1003 */
1004 value = inl(pr->throttling.address);
1005 if (value & 0x10) {
1006 value &= 0xFFFFFFEF;
1007 outl(value, pr->throttling.address);
1008 }
1009
1010 /*
1011 * Write the new duty_value and then enable throttling. Note
1012 * that a state value of 0 leaves throttling disabled.
1013 */
1014 if (state) {
1015 value &= duty_mask;
1016 value |= duty_value;
1017 outl(value, pr->throttling.address);
1018
1019 value |= 0x00000010;
1020 outl(value, pr->throttling.address);
1021 }
1022
1023 pr->throttling.state = state;
1024
1025 local_irq_enable();
1026
1027 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1028 "Throttling state set to T%d (%d%%)\n", state,
1029 (pr->throttling.states[state].performance ? pr->
1030 throttling.states[state].performance / 10 : 0)));
1031
1032 return 0;
1033 }
1034
1035 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1036 int state, bool force)
1037 {
1038 int ret;
1039 u64 value;
1040
1041 if (!pr)
1042 return -EINVAL;
1043
1044 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1045 return -EINVAL;
1046
1047 if (!pr->flags.throttling)
1048 return -ENODEV;
1049
1050 if (!force && (state == pr->throttling.state))
1051 return 0;
1052
1053 if (state < pr->throttling_platform_limit)
1054 return -EPERM;
1055
1056 value = 0;
1057 ret = acpi_get_throttling_value(pr, state, &value);
1058 if (ret >= 0) {
1059 acpi_write_throttling_state(pr, value);
1060 pr->throttling.state = state;
1061 }
1062
1063 return 0;
1064 }
1065
1066 int acpi_processor_set_throttling(struct acpi_processor *pr,
1067 int state, bool force)
1068 {
1069 cpumask_var_t saved_mask;
1070 int ret = 0;
1071 unsigned int i;
1072 struct acpi_processor *match_pr;
1073 struct acpi_processor_throttling *p_throttling;
1074 struct throttling_tstate t_state;
1075 cpumask_var_t online_throttling_cpus;
1076
1077 if (!pr)
1078 return -EINVAL;
1079
1080 if (!pr->flags.throttling)
1081 return -ENODEV;
1082
1083 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1084 return -EINVAL;
1085
1086 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1087 return -ENOMEM;
1088
1089 if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1090 free_cpumask_var(saved_mask);
1091 return -ENOMEM;
1092 }
1093
1094 if (cpu_is_offline(pr->id)) {
1095 /*
1096 * the cpu pointed by pr->id is offline. Unnecessary to change
1097 * the throttling state any more.
1098 */
1099 return -ENODEV;
1100 }
1101
1102 cpumask_copy(saved_mask, &current->cpus_allowed);
1103 t_state.target_state = state;
1104 p_throttling = &(pr->throttling);
1105 cpumask_and(online_throttling_cpus, cpu_online_mask,
1106 p_throttling->shared_cpu_map);
1107 /*
1108 * The throttling notifier will be called for every
1109 * affected cpu in order to get one proper T-state.
1110 * The notifier event is THROTTLING_PRECHANGE.
1111 */
1112 for_each_cpu(i, online_throttling_cpus) {
1113 t_state.cpu = i;
1114 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1115 &t_state);
1116 }
1117 /*
1118 * The function of acpi_processor_set_throttling will be called
1119 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1120 * it is necessary to call it for every affected cpu. Otherwise
1121 * it can be called only for the cpu pointed by pr.
1122 */
1123 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1124 /* FIXME: use work_on_cpu() */
1125 if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) {
1126 /* Can't migrate to the pr->id CPU. Exit */
1127 ret = -ENODEV;
1128 goto exit;
1129 }
1130 ret = p_throttling->acpi_processor_set_throttling(pr,
1131 t_state.target_state, force);
1132 } else {
1133 /*
1134 * When the T-state coordination is SW_ALL or HW_ALL,
1135 * it is necessary to set T-state for every affected
1136 * cpus.
1137 */
1138 for_each_cpu(i, online_throttling_cpus) {
1139 match_pr = per_cpu(processors, i);
1140 /*
1141 * If the pointer is invalid, we will report the
1142 * error message and continue.
1143 */
1144 if (!match_pr) {
1145 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1146 "Invalid Pointer for CPU %d\n", i));
1147 continue;
1148 }
1149 /*
1150 * If the throttling control is unsupported on CPU i,
1151 * we will report the error message and continue.
1152 */
1153 if (!match_pr->flags.throttling) {
1154 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1155 "Throttling Control is unsupported "
1156 "on CPU %d\n", i));
1157 continue;
1158 }
1159 t_state.cpu = i;
1160 /* FIXME: use work_on_cpu() */
1161 if (set_cpus_allowed_ptr(current, cpumask_of(i)))
1162 continue;
1163 ret = match_pr->throttling.
1164 acpi_processor_set_throttling(
1165 match_pr, t_state.target_state, force);
1166 }
1167 }
1168 /*
1169 * After the set_throttling is called, the
1170 * throttling notifier is called for every
1171 * affected cpu to update the T-states.
1172 * The notifier event is THROTTLING_POSTCHANGE
1173 */
1174 for_each_cpu(i, online_throttling_cpus) {
1175 t_state.cpu = i;
1176 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1177 &t_state);
1178 }
1179 /* restore the previous state */
1180 /* FIXME: use work_on_cpu() */
1181 set_cpus_allowed_ptr(current, saved_mask);
1182 exit:
1183 free_cpumask_var(online_throttling_cpus);
1184 free_cpumask_var(saved_mask);
1185 return ret;
1186 }
1187
1188 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1189 {
1190 int result = 0;
1191 struct acpi_processor_throttling *pthrottling;
1192
1193 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1194 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1195 pr->throttling.address,
1196 pr->throttling.duty_offset,
1197 pr->throttling.duty_width));
1198
1199 /*
1200 * Evaluate _PTC, _TSS and _TPC
1201 * They must all be present or none of them can be used.
1202 */
1203 if (acpi_processor_get_throttling_control(pr) ||
1204 acpi_processor_get_throttling_states(pr) ||
1205 acpi_processor_get_platform_limit(pr))
1206 {
1207 pr->throttling.acpi_processor_get_throttling =
1208 &acpi_processor_get_throttling_fadt;
1209 pr->throttling.acpi_processor_set_throttling =
1210 &acpi_processor_set_throttling_fadt;
1211 if (acpi_processor_get_fadt_info(pr))
1212 return 0;
1213 } else {
1214 pr->throttling.acpi_processor_get_throttling =
1215 &acpi_processor_get_throttling_ptc;
1216 pr->throttling.acpi_processor_set_throttling =
1217 &acpi_processor_set_throttling_ptc;
1218 }
1219
1220 /*
1221 * If TSD package for one CPU can't be parsed successfully, it means
1222 * that this CPU will have no coordination with other CPUs.
1223 */
1224 if (acpi_processor_get_tsd(pr)) {
1225 pthrottling = &pr->throttling;
1226 pthrottling->tsd_valid_flag = 0;
1227 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1228 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1229 }
1230
1231 /*
1232 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1233 * This shouldn't be an issue as few (if any) mobile systems ever
1234 * used this part.
1235 */
1236 if (errata.piix4.throttle) {
1237 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1238 "Throttling not supported on PIIX4 A- or B-step\n"));
1239 return 0;
1240 }
1241
1242 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1243 pr->throttling.state_count));
1244
1245 pr->flags.throttling = 1;
1246
1247 /*
1248 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1249 * thermal) decide to lower performance if it so chooses, but for now
1250 * we'll crank up the speed.
1251 */
1252
1253 result = acpi_processor_get_throttling(pr);
1254 if (result)
1255 goto end;
1256
1257 if (pr->throttling.state) {
1258 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1259 "Disabling throttling (was T%d)\n",
1260 pr->throttling.state));
1261 result = acpi_processor_set_throttling(pr, 0, false);
1262 if (result)
1263 goto end;
1264 }
1265
1266 end:
1267 if (result)
1268 pr->flags.throttling = 0;
1269
1270 return result;
1271 }
1272
x86 "subsystem" repository