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leds: bcm6358: merge bcm6358_led_mode and bcm6358_led_set
[deliverable/linux.git] / drivers / acpi / processor_throttling.c
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 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23 */
24
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/init.h>
29 #include <linux/sched.h>
30 #include <linux/cpufreq.h>
31 #include <linux/acpi.h>
32 #include <acpi/processor.h>
33 #include <asm/io.h>
34 #include <asm/uaccess.h>
35
36 #define PREFIX "ACPI: "
37
38 #define ACPI_PROCESSOR_CLASS "processor"
39 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
40 ACPI_MODULE_NAME("processor_throttling");
41
42 /* ignore_tpc:
43 * 0 -> acpi processor driver doesn't ignore _TPC values
44 * 1 -> acpi processor driver ignores _TPC values
45 */
46 static int ignore_tpc;
47 module_param(ignore_tpc, int, 0644);
48 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
49
50 struct throttling_tstate {
51 unsigned int cpu; /* cpu nr */
52 int target_state; /* target T-state */
53 };
54
55 struct acpi_processor_throttling_arg {
56 struct acpi_processor *pr;
57 int target_state;
58 bool force;
59 };
60
61 #define THROTTLING_PRECHANGE (1)
62 #define THROTTLING_POSTCHANGE (2)
63
64 static int acpi_processor_get_throttling(struct acpi_processor *pr);
65 int acpi_processor_set_throttling(struct acpi_processor *pr,
66 int state, bool force);
67
68 static int acpi_processor_update_tsd_coord(void)
69 {
70 int count, count_target;
71 int retval = 0;
72 unsigned int i, j;
73 cpumask_var_t covered_cpus;
74 struct acpi_processor *pr, *match_pr;
75 struct acpi_tsd_package *pdomain, *match_pdomain;
76 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
77
78 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
79 return -ENOMEM;
80
81 /*
82 * Now that we have _TSD data from all CPUs, lets setup T-state
83 * coordination between all CPUs.
84 */
85 for_each_possible_cpu(i) {
86 pr = per_cpu(processors, i);
87 if (!pr)
88 continue;
89
90 /* Basic validity check for domain info */
91 pthrottling = &(pr->throttling);
92
93 /*
94 * If tsd package for one cpu is invalid, the coordination
95 * among all CPUs is thought as invalid.
96 * Maybe it is ugly.
97 */
98 if (!pthrottling->tsd_valid_flag) {
99 retval = -EINVAL;
100 break;
101 }
102 }
103 if (retval)
104 goto err_ret;
105
106 for_each_possible_cpu(i) {
107 pr = per_cpu(processors, i);
108 if (!pr)
109 continue;
110
111 if (cpumask_test_cpu(i, covered_cpus))
112 continue;
113 pthrottling = &pr->throttling;
114
115 pdomain = &(pthrottling->domain_info);
116 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
117 cpumask_set_cpu(i, covered_cpus);
118 /*
119 * If the number of processor in the TSD domain is 1, it is
120 * unnecessary to parse the coordination for this CPU.
121 */
122 if (pdomain->num_processors <= 1)
123 continue;
124
125 /* Validate the Domain info */
126 count_target = pdomain->num_processors;
127 count = 1;
128
129 for_each_possible_cpu(j) {
130 if (i == j)
131 continue;
132
133 match_pr = per_cpu(processors, j);
134 if (!match_pr)
135 continue;
136
137 match_pthrottling = &(match_pr->throttling);
138 match_pdomain = &(match_pthrottling->domain_info);
139 if (match_pdomain->domain != pdomain->domain)
140 continue;
141
142 /* Here i and j are in the same domain.
143 * If two TSD packages have the same domain, they
144 * should have the same num_porcessors and
145 * coordination type. Otherwise it will be regarded
146 * as illegal.
147 */
148 if (match_pdomain->num_processors != count_target) {
149 retval = -EINVAL;
150 goto err_ret;
151 }
152
153 if (pdomain->coord_type != match_pdomain->coord_type) {
154 retval = -EINVAL;
155 goto err_ret;
156 }
157
158 cpumask_set_cpu(j, covered_cpus);
159 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
160 count++;
161 }
162 for_each_possible_cpu(j) {
163 if (i == j)
164 continue;
165
166 match_pr = per_cpu(processors, j);
167 if (!match_pr)
168 continue;
169
170 match_pthrottling = &(match_pr->throttling);
171 match_pdomain = &(match_pthrottling->domain_info);
172 if (match_pdomain->domain != pdomain->domain)
173 continue;
174
175 /*
176 * If some CPUS have the same domain, they
177 * will have the same shared_cpu_map.
178 */
179 cpumask_copy(match_pthrottling->shared_cpu_map,
180 pthrottling->shared_cpu_map);
181 }
182 }
183
184 err_ret:
185 free_cpumask_var(covered_cpus);
186
187 for_each_possible_cpu(i) {
188 pr = per_cpu(processors, i);
189 if (!pr)
190 continue;
191
192 /*
193 * Assume no coordination on any error parsing domain info.
194 * The coordination type will be forced as SW_ALL.
195 */
196 if (retval) {
197 pthrottling = &(pr->throttling);
198 cpumask_clear(pthrottling->shared_cpu_map);
199 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
200 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
201 }
202 }
203
204 return retval;
205 }
206
207 /*
208 * Update the T-state coordination after the _TSD
209 * data for all cpus is obtained.
210 */
211 void acpi_processor_throttling_init(void)
212 {
213 if (acpi_processor_update_tsd_coord()) {
214 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
215 "Assume no T-state coordination\n"));
216 }
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 u32 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 bit_width = throttling->status_register.bit_width;
781 bit_offset = throttling->status_register.bit_offset;
782
783 acpi_os_read_port((acpi_io_address) throttling->status_register.
784 address, &ptc_value,
785 (u32) (bit_width + bit_offset));
786 ptc_mask = (1 << bit_width) - 1;
787 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
788 ret = 0;
789 break;
790 case ACPI_ADR_SPACE_FIXED_HARDWARE:
791 ret = acpi_throttling_rdmsr(value);
792 break;
793 default:
794 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
795 (u32) (throttling->status_register.space_id));
796 }
797 return ret;
798 }
799
800 static int acpi_write_throttling_state(struct acpi_processor *pr,
801 u64 value)
802 {
803 u32 bit_width, bit_offset;
804 u64 ptc_value;
805 u64 ptc_mask;
806 struct acpi_processor_throttling *throttling;
807 int ret = -1;
808
809 throttling = &pr->throttling;
810 switch (throttling->control_register.space_id) {
811 case ACPI_ADR_SPACE_SYSTEM_IO:
812 bit_width = throttling->control_register.bit_width;
813 bit_offset = throttling->control_register.bit_offset;
814 ptc_mask = (1 << bit_width) - 1;
815 ptc_value = value & ptc_mask;
816
817 acpi_os_write_port((acpi_io_address) throttling->
818 control_register.address,
819 (u32) (ptc_value << bit_offset),
820 (u32) (bit_width + bit_offset));
821 ret = 0;
822 break;
823 case ACPI_ADR_SPACE_FIXED_HARDWARE:
824 ret = acpi_throttling_wrmsr(value);
825 break;
826 default:
827 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
828 (u32) (throttling->control_register.space_id));
829 }
830 return ret;
831 }
832
833 static int acpi_get_throttling_state(struct acpi_processor *pr,
834 u64 value)
835 {
836 int i;
837
838 for (i = 0; i < pr->throttling.state_count; i++) {
839 struct acpi_processor_tx_tss *tx =
840 (struct acpi_processor_tx_tss *)&(pr->throttling.
841 states_tss[i]);
842 if (tx->control == value)
843 return i;
844 }
845 return -1;
846 }
847
848 static int acpi_get_throttling_value(struct acpi_processor *pr,
849 int state, u64 *value)
850 {
851 int ret = -1;
852
853 if (state >= 0 && state <= pr->throttling.state_count) {
854 struct acpi_processor_tx_tss *tx =
855 (struct acpi_processor_tx_tss *)&(pr->throttling.
856 states_tss[state]);
857 *value = tx->control;
858 ret = 0;
859 }
860 return ret;
861 }
862
863 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
864 {
865 int state = 0;
866 int ret;
867 u64 value;
868
869 if (!pr)
870 return -EINVAL;
871
872 if (!pr->flags.throttling)
873 return -ENODEV;
874
875 pr->throttling.state = 0;
876
877 value = 0;
878 ret = acpi_read_throttling_status(pr, &value);
879 if (ret >= 0) {
880 state = acpi_get_throttling_state(pr, value);
881 if (state == -1) {
882 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
883 "Invalid throttling state, reset\n"));
884 state = 0;
885 ret = acpi_processor_set_throttling(pr, state, true);
886 if (ret)
887 return ret;
888 }
889 pr->throttling.state = state;
890 }
891
892 return 0;
893 }
894
895 static int acpi_processor_get_throttling(struct acpi_processor *pr)
896 {
897 cpumask_var_t saved_mask;
898 int ret;
899
900 if (!pr)
901 return -EINVAL;
902
903 if (!pr->flags.throttling)
904 return -ENODEV;
905
906 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
907 return -ENOMEM;
908
909 /*
910 * Migrate task to the cpu pointed by pr.
911 */
912 cpumask_copy(saved_mask, &current->cpus_allowed);
913 /* FIXME: use work_on_cpu() */
914 if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) {
915 /* Can't migrate to the target pr->id CPU. Exit */
916 free_cpumask_var(saved_mask);
917 return -ENODEV;
918 }
919 ret = pr->throttling.acpi_processor_get_throttling(pr);
920 /* restore the previous state */
921 set_cpus_allowed_ptr(current, saved_mask);
922 free_cpumask_var(saved_mask);
923
924 return ret;
925 }
926
927 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
928 {
929 int i, step;
930
931 if (!pr->throttling.address) {
932 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
933 return -EINVAL;
934 } else if (!pr->throttling.duty_width) {
935 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
936 return -EINVAL;
937 }
938 /* TBD: Support duty_cycle values that span bit 4. */
939 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
940 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
941 return -EINVAL;
942 }
943
944 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
945
946 /*
947 * Compute state values. Note that throttling displays a linear power
948 * performance relationship (at 50% performance the CPU will consume
949 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
950 */
951
952 step = (1000 / pr->throttling.state_count);
953
954 for (i = 0; i < pr->throttling.state_count; i++) {
955 pr->throttling.states[i].performance = 1000 - step * i;
956 pr->throttling.states[i].power = 1000 - step * i;
957 }
958 return 0;
959 }
960
961 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
962 int state, bool force)
963 {
964 u32 value = 0;
965 u32 duty_mask = 0;
966 u32 duty_value = 0;
967
968 if (!pr)
969 return -EINVAL;
970
971 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
972 return -EINVAL;
973
974 if (!pr->flags.throttling)
975 return -ENODEV;
976
977 if (!force && (state == pr->throttling.state))
978 return 0;
979
980 if (state < pr->throttling_platform_limit)
981 return -EPERM;
982 /*
983 * Calculate the duty_value and duty_mask.
984 */
985 if (state) {
986 duty_value = pr->throttling.state_count - state;
987
988 duty_value <<= pr->throttling.duty_offset;
989
990 /* Used to clear all duty_value bits */
991 duty_mask = pr->throttling.state_count - 1;
992
993 duty_mask <<= acpi_gbl_FADT.duty_offset;
994 duty_mask = ~duty_mask;
995 }
996
997 local_irq_disable();
998
999 /*
1000 * Disable throttling by writing a 0 to bit 4. Note that we must
1001 * turn it off before you can change the duty_value.
1002 */
1003 value = inl(pr->throttling.address);
1004 if (value & 0x10) {
1005 value &= 0xFFFFFFEF;
1006 outl(value, pr->throttling.address);
1007 }
1008
1009 /*
1010 * Write the new duty_value and then enable throttling. Note
1011 * that a state value of 0 leaves throttling disabled.
1012 */
1013 if (state) {
1014 value &= duty_mask;
1015 value |= duty_value;
1016 outl(value, pr->throttling.address);
1017
1018 value |= 0x00000010;
1019 outl(value, pr->throttling.address);
1020 }
1021
1022 pr->throttling.state = state;
1023
1024 local_irq_enable();
1025
1026 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1027 "Throttling state set to T%d (%d%%)\n", state,
1028 (pr->throttling.states[state].performance ? pr->
1029 throttling.states[state].performance / 10 : 0)));
1030
1031 return 0;
1032 }
1033
1034 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1035 int state, bool force)
1036 {
1037 int ret;
1038 u64 value;
1039
1040 if (!pr)
1041 return -EINVAL;
1042
1043 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1044 return -EINVAL;
1045
1046 if (!pr->flags.throttling)
1047 return -ENODEV;
1048
1049 if (!force && (state == pr->throttling.state))
1050 return 0;
1051
1052 if (state < pr->throttling_platform_limit)
1053 return -EPERM;
1054
1055 value = 0;
1056 ret = acpi_get_throttling_value(pr, state, &value);
1057 if (ret >= 0) {
1058 acpi_write_throttling_state(pr, value);
1059 pr->throttling.state = state;
1060 }
1061
1062 return 0;
1063 }
1064
1065 static long acpi_processor_throttling_fn(void *data)
1066 {
1067 struct acpi_processor_throttling_arg *arg = data;
1068 struct acpi_processor *pr = arg->pr;
1069
1070 return pr->throttling.acpi_processor_set_throttling(pr,
1071 arg->target_state, arg->force);
1072 }
1073
1074 int acpi_processor_set_throttling(struct acpi_processor *pr,
1075 int state, bool force)
1076 {
1077 int ret = 0;
1078 unsigned int i;
1079 struct acpi_processor *match_pr;
1080 struct acpi_processor_throttling *p_throttling;
1081 struct acpi_processor_throttling_arg arg;
1082 struct throttling_tstate t_state;
1083
1084 if (!pr)
1085 return -EINVAL;
1086
1087 if (!pr->flags.throttling)
1088 return -ENODEV;
1089
1090 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1091 return -EINVAL;
1092
1093 if (cpu_is_offline(pr->id)) {
1094 /*
1095 * the cpu pointed by pr->id is offline. Unnecessary to change
1096 * the throttling state any more.
1097 */
1098 return -ENODEV;
1099 }
1100
1101 t_state.target_state = state;
1102 p_throttling = &(pr->throttling);
1103
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_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
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 arg.pr = pr;
1122 arg.target_state = state;
1123 arg.force = force;
1124 ret = work_on_cpu(pr->id, acpi_processor_throttling_fn, &arg);
1125 } else {
1126 /*
1127 * When the T-state coordination is SW_ALL or HW_ALL,
1128 * it is necessary to set T-state for every affected
1129 * cpus.
1130 */
1131 for_each_cpu_and(i, cpu_online_mask,
1132 p_throttling->shared_cpu_map) {
1133 match_pr = per_cpu(processors, i);
1134 /*
1135 * If the pointer is invalid, we will report the
1136 * error message and continue.
1137 */
1138 if (!match_pr) {
1139 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1140 "Invalid Pointer for CPU %d\n", i));
1141 continue;
1142 }
1143 /*
1144 * If the throttling control is unsupported on CPU i,
1145 * we will report the error message and continue.
1146 */
1147 if (!match_pr->flags.throttling) {
1148 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1149 "Throttling Control is unsupported "
1150 "on CPU %d\n", i));
1151 continue;
1152 }
1153
1154 arg.pr = match_pr;
1155 arg.target_state = state;
1156 arg.force = force;
1157 ret = work_on_cpu(pr->id, acpi_processor_throttling_fn,
1158 &arg);
1159 }
1160 }
1161 /*
1162 * After the set_throttling is called, the
1163 * throttling notifier is called for every
1164 * affected cpu to update the T-states.
1165 * The notifier event is THROTTLING_POSTCHANGE
1166 */
1167 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1168 t_state.cpu = i;
1169 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1170 &t_state);
1171 }
1172
1173 return ret;
1174 }
1175
1176 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1177 {
1178 int result = 0;
1179 struct acpi_processor_throttling *pthrottling;
1180
1181 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1182 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1183 pr->throttling.address,
1184 pr->throttling.duty_offset,
1185 pr->throttling.duty_width));
1186
1187 /*
1188 * Evaluate _PTC, _TSS and _TPC
1189 * They must all be present or none of them can be used.
1190 */
1191 if (acpi_processor_get_throttling_control(pr) ||
1192 acpi_processor_get_throttling_states(pr) ||
1193 acpi_processor_get_platform_limit(pr))
1194 {
1195 pr->throttling.acpi_processor_get_throttling =
1196 &acpi_processor_get_throttling_fadt;
1197 pr->throttling.acpi_processor_set_throttling =
1198 &acpi_processor_set_throttling_fadt;
1199 if (acpi_processor_get_fadt_info(pr))
1200 return 0;
1201 } else {
1202 pr->throttling.acpi_processor_get_throttling =
1203 &acpi_processor_get_throttling_ptc;
1204 pr->throttling.acpi_processor_set_throttling =
1205 &acpi_processor_set_throttling_ptc;
1206 }
1207
1208 /*
1209 * If TSD package for one CPU can't be parsed successfully, it means
1210 * that this CPU will have no coordination with other CPUs.
1211 */
1212 if (acpi_processor_get_tsd(pr)) {
1213 pthrottling = &pr->throttling;
1214 pthrottling->tsd_valid_flag = 0;
1215 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1216 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1217 }
1218
1219 /*
1220 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1221 * This shouldn't be an issue as few (if any) mobile systems ever
1222 * used this part.
1223 */
1224 if (errata.piix4.throttle) {
1225 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1226 "Throttling not supported on PIIX4 A- or B-step\n"));
1227 return 0;
1228 }
1229
1230 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1231 pr->throttling.state_count));
1232
1233 pr->flags.throttling = 1;
1234
1235 /*
1236 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1237 * thermal) decide to lower performance if it so chooses, but for now
1238 * we'll crank up the speed.
1239 */
1240
1241 result = acpi_processor_get_throttling(pr);
1242 if (result)
1243 goto end;
1244
1245 if (pr->throttling.state) {
1246 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1247 "Disabling throttling (was T%d)\n",
1248 pr->throttling.state));
1249 result = acpi_processor_set_throttling(pr, 0, false);
1250 if (result)
1251 goto end;
1252 }
1253
1254 end:
1255 if (result)
1256 pr->flags.throttling = 0;
1257
1258 return result;
1259 }
1260
Linux kernel - Deliverables
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