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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * processor_throttling.c - Throttling submodule of the ACPI processor driver
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
8 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9 * - Added processor hotplug support
10 */
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/slab.h>
15#include <linux/init.h>
16#include <linux/sched.h>
17#include <linux/cpufreq.h>
18#include <linux/acpi.h>
19#include <acpi/processor.h>
20#include <asm/io.h>
21#include <linux/uaccess.h>
22
23#define PREFIX "ACPI: "
24
25#define ACPI_PROCESSOR_CLASS "processor"
26#define _COMPONENT ACPI_PROCESSOR_COMPONENT
27ACPI_MODULE_NAME("processor_throttling");
28
29/* ignore_tpc:
30 * 0 -> acpi processor driver doesn't ignore _TPC values
31 * 1 -> acpi processor driver ignores _TPC values
32 */
33static int ignore_tpc;
34module_param(ignore_tpc, int, 0644);
35MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
36
37struct throttling_tstate {
38 unsigned int cpu; /* cpu nr */
39 int target_state; /* target T-state */
40};
41
42struct acpi_processor_throttling_arg {
43 struct acpi_processor *pr;
44 int target_state;
45 bool force;
46};
47
48#define THROTTLING_PRECHANGE (1)
49#define THROTTLING_POSTCHANGE (2)
50
51static int acpi_processor_get_throttling(struct acpi_processor *pr);
52static int __acpi_processor_set_throttling(struct acpi_processor *pr,
53 int state, bool force, bool direct);
54
55static int acpi_processor_update_tsd_coord(void)
56{
57 int count, count_target;
58 int retval = 0;
59 unsigned int i, j;
60 cpumask_var_t covered_cpus;
61 struct acpi_processor *pr, *match_pr;
62 struct acpi_tsd_package *pdomain, *match_pdomain;
63 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
64
65 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
66 return -ENOMEM;
67
68 /*
69 * Now that we have _TSD data from all CPUs, lets setup T-state
70 * coordination between all CPUs.
71 */
72 for_each_possible_cpu(i) {
73 pr = per_cpu(processors, i);
74 if (!pr)
75 continue;
76
77 /* Basic validity check for domain info */
78 pthrottling = &(pr->throttling);
79
80 /*
81 * If tsd package for one cpu is invalid, the coordination
82 * among all CPUs is thought as invalid.
83 * Maybe it is ugly.
84 */
85 if (!pthrottling->tsd_valid_flag) {
86 retval = -EINVAL;
87 break;
88 }
89 }
90 if (retval)
91 goto err_ret;
92
93 for_each_possible_cpu(i) {
94 pr = per_cpu(processors, i);
95 if (!pr)
96 continue;
97
98 if (cpumask_test_cpu(i, covered_cpus))
99 continue;
100 pthrottling = &pr->throttling;
101
102 pdomain = &(pthrottling->domain_info);
103 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
104 cpumask_set_cpu(i, covered_cpus);
105 /*
106 * If the number of processor in the TSD domain is 1, it is
107 * unnecessary to parse the coordination for this CPU.
108 */
109 if (pdomain->num_processors <= 1)
110 continue;
111
112 /* Validate the Domain info */
113 count_target = pdomain->num_processors;
114 count = 1;
115
116 for_each_possible_cpu(j) {
117 if (i == j)
118 continue;
119
120 match_pr = per_cpu(processors, j);
121 if (!match_pr)
122 continue;
123
124 match_pthrottling = &(match_pr->throttling);
125 match_pdomain = &(match_pthrottling->domain_info);
126 if (match_pdomain->domain != pdomain->domain)
127 continue;
128
129 /* Here i and j are in the same domain.
130 * If two TSD packages have the same domain, they
131 * should have the same num_porcessors and
132 * coordination type. Otherwise it will be regarded
133 * as illegal.
134 */
135 if (match_pdomain->num_processors != count_target) {
136 retval = -EINVAL;
137 goto err_ret;
138 }
139
140 if (pdomain->coord_type != match_pdomain->coord_type) {
141 retval = -EINVAL;
142 goto err_ret;
143 }
144
145 cpumask_set_cpu(j, covered_cpus);
146 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
147 count++;
148 }
149 for_each_possible_cpu(j) {
150 if (i == j)
151 continue;
152
153 match_pr = per_cpu(processors, j);
154 if (!match_pr)
155 continue;
156
157 match_pthrottling = &(match_pr->throttling);
158 match_pdomain = &(match_pthrottling->domain_info);
159 if (match_pdomain->domain != pdomain->domain)
160 continue;
161
162 /*
163 * If some CPUS have the same domain, they
164 * will have the same shared_cpu_map.
165 */
166 cpumask_copy(match_pthrottling->shared_cpu_map,
167 pthrottling->shared_cpu_map);
168 }
169 }
170
171err_ret:
172 free_cpumask_var(covered_cpus);
173
174 for_each_possible_cpu(i) {
175 pr = per_cpu(processors, i);
176 if (!pr)
177 continue;
178
179 /*
180 * Assume no coordination on any error parsing domain info.
181 * The coordination type will be forced as SW_ALL.
182 */
183 if (retval) {
184 pthrottling = &(pr->throttling);
185 cpumask_clear(pthrottling->shared_cpu_map);
186 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
187 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
188 }
189 }
190
191 return retval;
192}
193
194/*
195 * Update the T-state coordination after the _TSD
196 * data for all cpus is obtained.
197 */
198void acpi_processor_throttling_init(void)
199{
200 if (acpi_processor_update_tsd_coord()) {
201 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
202 "Assume no T-state coordination\n"));
203 }
204
205 return;
206}
207
208static int acpi_processor_throttling_notifier(unsigned long event, void *data)
209{
210 struct throttling_tstate *p_tstate = data;
211 struct acpi_processor *pr;
212 unsigned int cpu ;
213 int target_state;
214 struct acpi_processor_limit *p_limit;
215 struct acpi_processor_throttling *p_throttling;
216
217 cpu = p_tstate->cpu;
218 pr = per_cpu(processors, cpu);
219 if (!pr) {
220 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
221 return 0;
222 }
223 if (!pr->flags.throttling) {
224 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
225 "unsupported on CPU %d\n", cpu));
226 return 0;
227 }
228 target_state = p_tstate->target_state;
229 p_throttling = &(pr->throttling);
230 switch (event) {
231 case THROTTLING_PRECHANGE:
232 /*
233 * Prechange event is used to choose one proper t-state,
234 * which meets the limits of thermal, user and _TPC.
235 */
236 p_limit = &pr->limit;
237 if (p_limit->thermal.tx > target_state)
238 target_state = p_limit->thermal.tx;
239 if (p_limit->user.tx > target_state)
240 target_state = p_limit->user.tx;
241 if (pr->throttling_platform_limit > target_state)
242 target_state = pr->throttling_platform_limit;
243 if (target_state >= p_throttling->state_count) {
244 printk(KERN_WARNING
245 "Exceed the limit of T-state \n");
246 target_state = p_throttling->state_count - 1;
247 }
248 p_tstate->target_state = target_state;
249 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
250 "target T-state of CPU %d is T%d\n",
251 cpu, target_state));
252 break;
253 case THROTTLING_POSTCHANGE:
254 /*
255 * Postchange event is only used to update the
256 * T-state flag of acpi_processor_throttling.
257 */
258 p_throttling->state = target_state;
259 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
260 "CPU %d is switched to T%d\n",
261 cpu, target_state));
262 break;
263 default:
264 printk(KERN_WARNING
265 "Unsupported Throttling notifier event\n");
266 break;
267 }
268
269 return 0;
270}
271
272/*
273 * _TPC - Throttling Present Capabilities
274 */
275static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
276{
277 acpi_status status = 0;
278 unsigned long long tpc = 0;
279
280 if (!pr)
281 return -EINVAL;
282
283 if (ignore_tpc)
284 goto end;
285
286 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
287 if (ACPI_FAILURE(status)) {
288 if (status != AE_NOT_FOUND) {
289 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
290 }
291 return -ENODEV;
292 }
293
294end:
295 pr->throttling_platform_limit = (int)tpc;
296 return 0;
297}
298
299int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
300{
301 int result = 0;
302 int throttling_limit;
303 int current_state;
304 struct acpi_processor_limit *limit;
305 int target_state;
306
307 if (ignore_tpc)
308 return 0;
309
310 result = acpi_processor_get_platform_limit(pr);
311 if (result) {
312 /* Throttling Limit is unsupported */
313 return result;
314 }
315
316 throttling_limit = pr->throttling_platform_limit;
317 if (throttling_limit >= pr->throttling.state_count) {
318 /* Uncorrect Throttling Limit */
319 return -EINVAL;
320 }
321
322 current_state = pr->throttling.state;
323 if (current_state > throttling_limit) {
324 /*
325 * The current state can meet the requirement of
326 * _TPC limit. But it is reasonable that OSPM changes
327 * t-states from high to low for better performance.
328 * Of course the limit condition of thermal
329 * and user should be considered.
330 */
331 limit = &pr->limit;
332 target_state = throttling_limit;
333 if (limit->thermal.tx > target_state)
334 target_state = limit->thermal.tx;
335 if (limit->user.tx > target_state)
336 target_state = limit->user.tx;
337 } else if (current_state == throttling_limit) {
338 /*
339 * Unnecessary to change the throttling state
340 */
341 return 0;
342 } else {
343 /*
344 * If the current state is lower than the limit of _TPC, it
345 * will be forced to switch to the throttling state defined
346 * by throttling_platfor_limit.
347 * Because the previous state meets with the limit condition
348 * of thermal and user, it is unnecessary to check it again.
349 */
350 target_state = throttling_limit;
351 }
352 return acpi_processor_set_throttling(pr, target_state, false);
353}
354
355/*
356 * This function is used to reevaluate whether the T-state is valid
357 * after one CPU is onlined/offlined.
358 * It is noted that it won't reevaluate the following properties for
359 * the T-state.
360 * 1. Control method.
361 * 2. the number of supported T-state
362 * 3. TSD domain
363 */
364void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
365 bool is_dead)
366{
367 int result = 0;
368
369 if (is_dead) {
370 /* When one CPU is offline, the T-state throttling
371 * will be invalidated.
372 */
373 pr->flags.throttling = 0;
374 return;
375 }
376 /* the following is to recheck whether the T-state is valid for
377 * the online CPU
378 */
379 if (!pr->throttling.state_count) {
380 /* If the number of T-state is invalid, it is
381 * invalidated.
382 */
383 pr->flags.throttling = 0;
384 return;
385 }
386 pr->flags.throttling = 1;
387
388 /* Disable throttling (if enabled). We'll let subsequent
389 * policy (e.g.thermal) decide to lower performance if it
390 * so chooses, but for now we'll crank up the speed.
391 */
392
393 result = acpi_processor_get_throttling(pr);
394 if (result)
395 goto end;
396
397 if (pr->throttling.state) {
398 result = acpi_processor_set_throttling(pr, 0, false);
399 if (result)
400 goto end;
401 }
402
403end:
404 if (result)
405 pr->flags.throttling = 0;
406}
407/*
408 * _PTC - Processor Throttling Control (and status) register location
409 */
410static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
411{
412 int result = 0;
413 acpi_status status = 0;
414 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
415 union acpi_object *ptc = NULL;
416 union acpi_object obj = { 0 };
417 struct acpi_processor_throttling *throttling;
418
419 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
420 if (ACPI_FAILURE(status)) {
421 if (status != AE_NOT_FOUND) {
422 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
423 }
424 return -ENODEV;
425 }
426
427 ptc = (union acpi_object *)buffer.pointer;
428 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
429 || (ptc->package.count != 2)) {
430 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
431 result = -EFAULT;
432 goto end;
433 }
434
435 /*
436 * control_register
437 */
438
439 obj = ptc->package.elements[0];
440
441 if ((obj.type != ACPI_TYPE_BUFFER)
442 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
443 || (obj.buffer.pointer == NULL)) {
444 printk(KERN_ERR PREFIX
445 "Invalid _PTC data (control_register)\n");
446 result = -EFAULT;
447 goto end;
448 }
449 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
450 sizeof(struct acpi_ptc_register));
451
452 /*
453 * status_register
454 */
455
456 obj = ptc->package.elements[1];
457
458 if ((obj.type != ACPI_TYPE_BUFFER)
459 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
460 || (obj.buffer.pointer == NULL)) {
461 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
462 result = -EFAULT;
463 goto end;
464 }
465
466 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
467 sizeof(struct acpi_ptc_register));
468
469 throttling = &pr->throttling;
470
471 if ((throttling->control_register.bit_width +
472 throttling->control_register.bit_offset) > 32) {
473 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
474 result = -EFAULT;
475 goto end;
476 }
477
478 if ((throttling->status_register.bit_width +
479 throttling->status_register.bit_offset) > 32) {
480 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
481 result = -EFAULT;
482 goto end;
483 }
484
485 end:
486 kfree(buffer.pointer);
487
488 return result;
489}
490
491/*
492 * _TSS - Throttling Supported States
493 */
494static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
495{
496 int result = 0;
497 acpi_status status = AE_OK;
498 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
499 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
500 struct acpi_buffer state = { 0, NULL };
501 union acpi_object *tss = NULL;
502 int i;
503
504 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
505 if (ACPI_FAILURE(status)) {
506 if (status != AE_NOT_FOUND) {
507 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
508 }
509 return -ENODEV;
510 }
511
512 tss = buffer.pointer;
513 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
514 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
515 result = -EFAULT;
516 goto end;
517 }
518
519 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
520 tss->package.count));
521
522 pr->throttling.state_count = tss->package.count;
523 pr->throttling.states_tss =
524 kmalloc_array(tss->package.count,
525 sizeof(struct acpi_processor_tx_tss),
526 GFP_KERNEL);
527 if (!pr->throttling.states_tss) {
528 result = -ENOMEM;
529 goto end;
530 }
531
532 for (i = 0; i < pr->throttling.state_count; i++) {
533
534 struct acpi_processor_tx_tss *tx =
535 (struct acpi_processor_tx_tss *)&(pr->throttling.
536 states_tss[i]);
537
538 state.length = sizeof(struct acpi_processor_tx_tss);
539 state.pointer = tx;
540
541 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
542
543 status = acpi_extract_package(&(tss->package.elements[i]),
544 &format, &state);
545 if (ACPI_FAILURE(status)) {
546 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
547 result = -EFAULT;
548 kfree(pr->throttling.states_tss);
549 goto end;
550 }
551
552 if (!tx->freqpercentage) {
553 printk(KERN_ERR PREFIX
554 "Invalid _TSS data: freq is zero\n");
555 result = -EFAULT;
556 kfree(pr->throttling.states_tss);
557 goto end;
558 }
559 }
560
561 end:
562 kfree(buffer.pointer);
563
564 return result;
565}
566
567/*
568 * _TSD - T-State Dependencies
569 */
570static int acpi_processor_get_tsd(struct acpi_processor *pr)
571{
572 int result = 0;
573 acpi_status status = AE_OK;
574 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
575 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
576 struct acpi_buffer state = { 0, NULL };
577 union acpi_object *tsd = NULL;
578 struct acpi_tsd_package *pdomain;
579 struct acpi_processor_throttling *pthrottling;
580
581 pthrottling = &pr->throttling;
582 pthrottling->tsd_valid_flag = 0;
583
584 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
585 if (ACPI_FAILURE(status)) {
586 if (status != AE_NOT_FOUND) {
587 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
588 }
589 return -ENODEV;
590 }
591
592 tsd = buffer.pointer;
593 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
594 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
595 result = -EFAULT;
596 goto end;
597 }
598
599 if (tsd->package.count != 1) {
600 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
601 result = -EFAULT;
602 goto end;
603 }
604
605 pdomain = &(pr->throttling.domain_info);
606
607 state.length = sizeof(struct acpi_tsd_package);
608 state.pointer = pdomain;
609
610 status = acpi_extract_package(&(tsd->package.elements[0]),
611 &format, &state);
612 if (ACPI_FAILURE(status)) {
613 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
614 result = -EFAULT;
615 goto end;
616 }
617
618 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
619 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
620 result = -EFAULT;
621 goto end;
622 }
623
624 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
625 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
626 result = -EFAULT;
627 goto end;
628 }
629
630 pthrottling = &pr->throttling;
631 pthrottling->tsd_valid_flag = 1;
632 pthrottling->shared_type = pdomain->coord_type;
633 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
634 /*
635 * If the coordination type is not defined in ACPI spec,
636 * the tsd_valid_flag will be clear and coordination type
637 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
638 */
639 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
640 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
641 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
642 pthrottling->tsd_valid_flag = 0;
643 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
644 }
645
646 end:
647 kfree(buffer.pointer);
648 return result;
649}
650
651/* --------------------------------------------------------------------------
652 Throttling Control
653 -------------------------------------------------------------------------- */
654static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
655{
656 int state = 0;
657 u32 value = 0;
658 u32 duty_mask = 0;
659 u32 duty_value = 0;
660
661 if (!pr)
662 return -EINVAL;
663
664 if (!pr->flags.throttling)
665 return -ENODEV;
666
667 /*
668 * We don't care about error returns - we just try to mark
669 * these reserved so that nobody else is confused into thinking
670 * that this region might be unused..
671 *
672 * (In particular, allocating the IO range for Cardbus)
673 */
674 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
675
676 pr->throttling.state = 0;
677
678 duty_mask = pr->throttling.state_count - 1;
679
680 duty_mask <<= pr->throttling.duty_offset;
681
682 local_irq_disable();
683
684 value = inl(pr->throttling.address);
685
686 /*
687 * Compute the current throttling state when throttling is enabled
688 * (bit 4 is on).
689 */
690 if (value & 0x10) {
691 duty_value = value & duty_mask;
692 duty_value >>= pr->throttling.duty_offset;
693
694 if (duty_value)
695 state = pr->throttling.state_count - duty_value;
696 }
697
698 pr->throttling.state = state;
699
700 local_irq_enable();
701
702 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
703 "Throttling state is T%d (%d%% throttling applied)\n",
704 state, pr->throttling.states[state].performance));
705
706 return 0;
707}
708
709#ifdef CONFIG_X86
710static int acpi_throttling_rdmsr(u64 *value)
711{
712 u64 msr_high, msr_low;
713 u64 msr = 0;
714 int ret = -1;
715
716 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
717 !this_cpu_has(X86_FEATURE_ACPI)) {
718 printk(KERN_ERR PREFIX
719 "HARDWARE addr space,NOT supported yet\n");
720 } else {
721 msr_low = 0;
722 msr_high = 0;
723 rdmsr_safe(MSR_IA32_THERM_CONTROL,
724 (u32 *)&msr_low , (u32 *) &msr_high);
725 msr = (msr_high << 32) | msr_low;
726 *value = (u64) msr;
727 ret = 0;
728 }
729 return ret;
730}
731
732static int acpi_throttling_wrmsr(u64 value)
733{
734 int ret = -1;
735 u64 msr;
736
737 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
738 !this_cpu_has(X86_FEATURE_ACPI)) {
739 printk(KERN_ERR PREFIX
740 "HARDWARE addr space,NOT supported yet\n");
741 } else {
742 msr = value;
743 wrmsr_safe(MSR_IA32_THERM_CONTROL,
744 msr & 0xffffffff, msr >> 32);
745 ret = 0;
746 }
747 return ret;
748}
749#else
750static int acpi_throttling_rdmsr(u64 *value)
751{
752 printk(KERN_ERR PREFIX
753 "HARDWARE addr space,NOT supported yet\n");
754 return -1;
755}
756
757static int acpi_throttling_wrmsr(u64 value)
758{
759 printk(KERN_ERR PREFIX
760 "HARDWARE addr space,NOT supported yet\n");
761 return -1;
762}
763#endif
764
765static int acpi_read_throttling_status(struct acpi_processor *pr,
766 u64 *value)
767{
768 u32 bit_width, bit_offset;
769 u32 ptc_value;
770 u64 ptc_mask;
771 struct acpi_processor_throttling *throttling;
772 int ret = -1;
773
774 throttling = &pr->throttling;
775 switch (throttling->status_register.space_id) {
776 case ACPI_ADR_SPACE_SYSTEM_IO:
777 bit_width = throttling->status_register.bit_width;
778 bit_offset = throttling->status_register.bit_offset;
779
780 acpi_os_read_port((acpi_io_address) throttling->status_register.
781 address, &ptc_value,
782 (u32) (bit_width + bit_offset));
783 ptc_mask = (1 << bit_width) - 1;
784 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
785 ret = 0;
786 break;
787 case ACPI_ADR_SPACE_FIXED_HARDWARE:
788 ret = acpi_throttling_rdmsr(value);
789 break;
790 default:
791 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
792 (u32) (throttling->status_register.space_id));
793 }
794 return ret;
795}
796
797static int acpi_write_throttling_state(struct acpi_processor *pr,
798 u64 value)
799{
800 u32 bit_width, bit_offset;
801 u64 ptc_value;
802 u64 ptc_mask;
803 struct acpi_processor_throttling *throttling;
804 int ret = -1;
805
806 throttling = &pr->throttling;
807 switch (throttling->control_register.space_id) {
808 case ACPI_ADR_SPACE_SYSTEM_IO:
809 bit_width = throttling->control_register.bit_width;
810 bit_offset = throttling->control_register.bit_offset;
811 ptc_mask = (1 << bit_width) - 1;
812 ptc_value = value & ptc_mask;
813
814 acpi_os_write_port((acpi_io_address) throttling->
815 control_register.address,
816 (u32) (ptc_value << bit_offset),
817 (u32) (bit_width + bit_offset));
818 ret = 0;
819 break;
820 case ACPI_ADR_SPACE_FIXED_HARDWARE:
821 ret = acpi_throttling_wrmsr(value);
822 break;
823 default:
824 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
825 (u32) (throttling->control_register.space_id));
826 }
827 return ret;
828}
829
830static int acpi_get_throttling_state(struct acpi_processor *pr,
831 u64 value)
832{
833 int i;
834
835 for (i = 0; i < pr->throttling.state_count; i++) {
836 struct acpi_processor_tx_tss *tx =
837 (struct acpi_processor_tx_tss *)&(pr->throttling.
838 states_tss[i]);
839 if (tx->control == value)
840 return i;
841 }
842 return -1;
843}
844
845static int acpi_get_throttling_value(struct acpi_processor *pr,
846 int state, u64 *value)
847{
848 int ret = -1;
849
850 if (state >= 0 && state <= pr->throttling.state_count) {
851 struct acpi_processor_tx_tss *tx =
852 (struct acpi_processor_tx_tss *)&(pr->throttling.
853 states_tss[state]);
854 *value = tx->control;
855 ret = 0;
856 }
857 return ret;
858}
859
860static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
861{
862 int state = 0;
863 int ret;
864 u64 value;
865
866 if (!pr)
867 return -EINVAL;
868
869 if (!pr->flags.throttling)
870 return -ENODEV;
871
872 pr->throttling.state = 0;
873
874 value = 0;
875 ret = acpi_read_throttling_status(pr, &value);
876 if (ret >= 0) {
877 state = acpi_get_throttling_state(pr, value);
878 if (state == -1) {
879 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
880 "Invalid throttling state, reset\n"));
881 state = 0;
882 ret = __acpi_processor_set_throttling(pr, state, true,
883 true);
884 if (ret)
885 return ret;
886 }
887 pr->throttling.state = state;
888 }
889
890 return 0;
891}
892
893static long __acpi_processor_get_throttling(void *data)
894{
895 struct acpi_processor *pr = data;
896
897 return pr->throttling.acpi_processor_get_throttling(pr);
898}
899
900static int acpi_processor_get_throttling(struct acpi_processor *pr)
901{
902 if (!pr)
903 return -EINVAL;
904
905 if (!pr->flags.throttling)
906 return -ENODEV;
907
908 /*
909 * This is either called from the CPU hotplug callback of
910 * processor_driver or via the ACPI probe function. In the latter
911 * case the CPU is not guaranteed to be online. Both call sites are
912 * protected against CPU hotplug.
913 */
914 if (!cpu_online(pr->id))
915 return -ENODEV;
916
917 return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false);
918}
919
920static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
921{
922 int i, step;
923
924 if (!pr->throttling.address) {
925 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
926 return -EINVAL;
927 } else if (!pr->throttling.duty_width) {
928 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
929 return -EINVAL;
930 }
931 /* TBD: Support duty_cycle values that span bit 4. */
932 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
933 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
934 return -EINVAL;
935 }
936
937 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
938
939 /*
940 * Compute state values. Note that throttling displays a linear power
941 * performance relationship (at 50% performance the CPU will consume
942 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
943 */
944
945 step = (1000 / pr->throttling.state_count);
946
947 for (i = 0; i < pr->throttling.state_count; i++) {
948 pr->throttling.states[i].performance = 1000 - step * i;
949 pr->throttling.states[i].power = 1000 - step * i;
950 }
951 return 0;
952}
953
954static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
955 int state, bool force)
956{
957 u32 value = 0;
958 u32 duty_mask = 0;
959 u32 duty_value = 0;
960
961 if (!pr)
962 return -EINVAL;
963
964 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
965 return -EINVAL;
966
967 if (!pr->flags.throttling)
968 return -ENODEV;
969
970 if (!force && (state == pr->throttling.state))
971 return 0;
972
973 if (state < pr->throttling_platform_limit)
974 return -EPERM;
975 /*
976 * Calculate the duty_value and duty_mask.
977 */
978 if (state) {
979 duty_value = pr->throttling.state_count - state;
980
981 duty_value <<= pr->throttling.duty_offset;
982
983 /* Used to clear all duty_value bits */
984 duty_mask = pr->throttling.state_count - 1;
985
986 duty_mask <<= acpi_gbl_FADT.duty_offset;
987 duty_mask = ~duty_mask;
988 }
989
990 local_irq_disable();
991
992 /*
993 * Disable throttling by writing a 0 to bit 4. Note that we must
994 * turn it off before you can change the duty_value.
995 */
996 value = inl(pr->throttling.address);
997 if (value & 0x10) {
998 value &= 0xFFFFFFEF;
999 outl(value, pr->throttling.address);
1000 }
1001
1002 /*
1003 * Write the new duty_value and then enable throttling. Note
1004 * that a state value of 0 leaves throttling disabled.
1005 */
1006 if (state) {
1007 value &= duty_mask;
1008 value |= duty_value;
1009 outl(value, pr->throttling.address);
1010
1011 value |= 0x00000010;
1012 outl(value, pr->throttling.address);
1013 }
1014
1015 pr->throttling.state = state;
1016
1017 local_irq_enable();
1018
1019 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1020 "Throttling state set to T%d (%d%%)\n", state,
1021 (pr->throttling.states[state].performance ? pr->
1022 throttling.states[state].performance / 10 : 0)));
1023
1024 return 0;
1025}
1026
1027static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1028 int state, bool force)
1029{
1030 int ret;
1031 u64 value;
1032
1033 if (!pr)
1034 return -EINVAL;
1035
1036 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1037 return -EINVAL;
1038
1039 if (!pr->flags.throttling)
1040 return -ENODEV;
1041
1042 if (!force && (state == pr->throttling.state))
1043 return 0;
1044
1045 if (state < pr->throttling_platform_limit)
1046 return -EPERM;
1047
1048 value = 0;
1049 ret = acpi_get_throttling_value(pr, state, &value);
1050 if (ret >= 0) {
1051 acpi_write_throttling_state(pr, value);
1052 pr->throttling.state = state;
1053 }
1054
1055 return 0;
1056}
1057
1058static long acpi_processor_throttling_fn(void *data)
1059{
1060 struct acpi_processor_throttling_arg *arg = data;
1061 struct acpi_processor *pr = arg->pr;
1062
1063 return pr->throttling.acpi_processor_set_throttling(pr,
1064 arg->target_state, arg->force);
1065}
1066
1067static int __acpi_processor_set_throttling(struct acpi_processor *pr,
1068 int state, bool force, bool direct)
1069{
1070 int ret = 0;
1071 unsigned int i;
1072 struct acpi_processor *match_pr;
1073 struct acpi_processor_throttling *p_throttling;
1074 struct acpi_processor_throttling_arg arg;
1075 struct throttling_tstate t_state;
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 (cpu_is_offline(pr->id)) {
1087 /*
1088 * the cpu pointed by pr->id is offline. Unnecessary to change
1089 * the throttling state any more.
1090 */
1091 return -ENODEV;
1092 }
1093
1094 t_state.target_state = state;
1095 p_throttling = &(pr->throttling);
1096
1097 /*
1098 * The throttling notifier will be called for every
1099 * affected cpu in order to get one proper T-state.
1100 * The notifier event is THROTTLING_PRECHANGE.
1101 */
1102 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1103 t_state.cpu = i;
1104 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1105 &t_state);
1106 }
1107 /*
1108 * The function of acpi_processor_set_throttling will be called
1109 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1110 * it is necessary to call it for every affected cpu. Otherwise
1111 * it can be called only for the cpu pointed by pr.
1112 */
1113 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1114 arg.pr = pr;
1115 arg.target_state = state;
1116 arg.force = force;
1117 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg,
1118 direct);
1119 } else {
1120 /*
1121 * When the T-state coordination is SW_ALL or HW_ALL,
1122 * it is necessary to set T-state for every affected
1123 * cpus.
1124 */
1125 for_each_cpu_and(i, cpu_online_mask,
1126 p_throttling->shared_cpu_map) {
1127 match_pr = per_cpu(processors, i);
1128 /*
1129 * If the pointer is invalid, we will report the
1130 * error message and continue.
1131 */
1132 if (!match_pr) {
1133 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1134 "Invalid Pointer for CPU %d\n", i));
1135 continue;
1136 }
1137 /*
1138 * If the throttling control is unsupported on CPU i,
1139 * we will report the error message and continue.
1140 */
1141 if (!match_pr->flags.throttling) {
1142 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1143 "Throttling Control is unsupported "
1144 "on CPU %d\n", i));
1145 continue;
1146 }
1147
1148 arg.pr = match_pr;
1149 arg.target_state = state;
1150 arg.force = force;
1151 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn,
1152 &arg, direct);
1153 }
1154 }
1155 /*
1156 * After the set_throttling is called, the
1157 * throttling notifier is called for every
1158 * affected cpu to update the T-states.
1159 * The notifier event is THROTTLING_POSTCHANGE
1160 */
1161 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1162 t_state.cpu = i;
1163 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1164 &t_state);
1165 }
1166
1167 return ret;
1168}
1169
1170int acpi_processor_set_throttling(struct acpi_processor *pr, int state,
1171 bool force)
1172{
1173 return __acpi_processor_set_throttling(pr, state, force, false);
1174}
1175
1176int 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
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
44ACPI_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 */
50static int ignore_tpc;
51module_param(ignore_tpc, int, 0644);
52MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
53
54struct throttling_tstate {
55 unsigned int cpu; /* cpu nr */
56 int target_state; /* target T-state */
57};
58
59struct acpi_processor_throttling_arg {
60 struct acpi_processor *pr;
61 int target_state;
62 bool force;
63};
64
65#define THROTTLING_PRECHANGE (1)
66#define THROTTLING_POSTCHANGE (2)
67
68static int acpi_processor_get_throttling(struct acpi_processor *pr);
69int acpi_processor_set_throttling(struct acpi_processor *pr,
70 int state, bool force);
71
72static int acpi_processor_update_tsd_coord(void)
73{
74 int count, count_target;
75 int retval = 0;
76 unsigned int i, j;
77 cpumask_var_t covered_cpus;
78 struct acpi_processor *pr, *match_pr;
79 struct acpi_tsd_package *pdomain, *match_pdomain;
80 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
81
82 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
83 return -ENOMEM;
84
85 /*
86 * Now that we have _TSD data from all CPUs, lets setup T-state
87 * coordination between all CPUs.
88 */
89 for_each_possible_cpu(i) {
90 pr = per_cpu(processors, i);
91 if (!pr)
92 continue;
93
94 /* Basic validity check for domain info */
95 pthrottling = &(pr->throttling);
96
97 /*
98 * If tsd package for one cpu is invalid, the coordination
99 * among all CPUs is thought as invalid.
100 * Maybe it is ugly.
101 */
102 if (!pthrottling->tsd_valid_flag) {
103 retval = -EINVAL;
104 break;
105 }
106 }
107 if (retval)
108 goto err_ret;
109
110 for_each_possible_cpu(i) {
111 pr = per_cpu(processors, i);
112 if (!pr)
113 continue;
114
115 if (cpumask_test_cpu(i, covered_cpus))
116 continue;
117 pthrottling = &pr->throttling;
118
119 pdomain = &(pthrottling->domain_info);
120 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
121 cpumask_set_cpu(i, covered_cpus);
122 /*
123 * If the number of processor in the TSD domain is 1, it is
124 * unnecessary to parse the coordination for this CPU.
125 */
126 if (pdomain->num_processors <= 1)
127 continue;
128
129 /* Validate the Domain info */
130 count_target = pdomain->num_processors;
131 count = 1;
132
133 for_each_possible_cpu(j) {
134 if (i == j)
135 continue;
136
137 match_pr = per_cpu(processors, j);
138 if (!match_pr)
139 continue;
140
141 match_pthrottling = &(match_pr->throttling);
142 match_pdomain = &(match_pthrottling->domain_info);
143 if (match_pdomain->domain != pdomain->domain)
144 continue;
145
146 /* Here i and j are in the same domain.
147 * If two TSD packages have the same domain, they
148 * should have the same num_porcessors and
149 * coordination type. Otherwise it will be regarded
150 * as illegal.
151 */
152 if (match_pdomain->num_processors != count_target) {
153 retval = -EINVAL;
154 goto err_ret;
155 }
156
157 if (pdomain->coord_type != match_pdomain->coord_type) {
158 retval = -EINVAL;
159 goto err_ret;
160 }
161
162 cpumask_set_cpu(j, covered_cpus);
163 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
164 count++;
165 }
166 for_each_possible_cpu(j) {
167 if (i == j)
168 continue;
169
170 match_pr = per_cpu(processors, j);
171 if (!match_pr)
172 continue;
173
174 match_pthrottling = &(match_pr->throttling);
175 match_pdomain = &(match_pthrottling->domain_info);
176 if (match_pdomain->domain != pdomain->domain)
177 continue;
178
179 /*
180 * If some CPUS have the same domain, they
181 * will have the same shared_cpu_map.
182 */
183 cpumask_copy(match_pthrottling->shared_cpu_map,
184 pthrottling->shared_cpu_map);
185 }
186 }
187
188err_ret:
189 free_cpumask_var(covered_cpus);
190
191 for_each_possible_cpu(i) {
192 pr = per_cpu(processors, i);
193 if (!pr)
194 continue;
195
196 /*
197 * Assume no coordination on any error parsing domain info.
198 * The coordination type will be forced as SW_ALL.
199 */
200 if (retval) {
201 pthrottling = &(pr->throttling);
202 cpumask_clear(pthrottling->shared_cpu_map);
203 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
204 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
205 }
206 }
207
208 return retval;
209}
210
211/*
212 * Update the T-state coordination after the _TSD
213 * data for all cpus is obtained.
214 */
215void acpi_processor_throttling_init(void)
216{
217 if (acpi_processor_update_tsd_coord()) {
218 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
219 "Assume no T-state coordination\n"));
220 }
221
222 return;
223}
224
225static int acpi_processor_throttling_notifier(unsigned long event, void *data)
226{
227 struct throttling_tstate *p_tstate = data;
228 struct acpi_processor *pr;
229 unsigned int cpu ;
230 int target_state;
231 struct acpi_processor_limit *p_limit;
232 struct acpi_processor_throttling *p_throttling;
233
234 cpu = p_tstate->cpu;
235 pr = per_cpu(processors, cpu);
236 if (!pr) {
237 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
238 return 0;
239 }
240 if (!pr->flags.throttling) {
241 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
242 "unsupported on CPU %d\n", cpu));
243 return 0;
244 }
245 target_state = p_tstate->target_state;
246 p_throttling = &(pr->throttling);
247 switch (event) {
248 case THROTTLING_PRECHANGE:
249 /*
250 * Prechange event is used to choose one proper t-state,
251 * which meets the limits of thermal, user and _TPC.
252 */
253 p_limit = &pr->limit;
254 if (p_limit->thermal.tx > target_state)
255 target_state = p_limit->thermal.tx;
256 if (p_limit->user.tx > target_state)
257 target_state = p_limit->user.tx;
258 if (pr->throttling_platform_limit > target_state)
259 target_state = pr->throttling_platform_limit;
260 if (target_state >= p_throttling->state_count) {
261 printk(KERN_WARNING
262 "Exceed the limit of T-state \n");
263 target_state = p_throttling->state_count - 1;
264 }
265 p_tstate->target_state = target_state;
266 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
267 "target T-state of CPU %d is T%d\n",
268 cpu, target_state));
269 break;
270 case THROTTLING_POSTCHANGE:
271 /*
272 * Postchange event is only used to update the
273 * T-state flag of acpi_processor_throttling.
274 */
275 p_throttling->state = target_state;
276 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
277 "CPU %d is switched to T%d\n",
278 cpu, target_state));
279 break;
280 default:
281 printk(KERN_WARNING
282 "Unsupported Throttling notifier event\n");
283 break;
284 }
285
286 return 0;
287}
288
289/*
290 * _TPC - Throttling Present Capabilities
291 */
292static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
293{
294 acpi_status status = 0;
295 unsigned long long tpc = 0;
296
297 if (!pr)
298 return -EINVAL;
299
300 if (ignore_tpc)
301 goto end;
302
303 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
304 if (ACPI_FAILURE(status)) {
305 if (status != AE_NOT_FOUND) {
306 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
307 }
308 return -ENODEV;
309 }
310
311end:
312 pr->throttling_platform_limit = (int)tpc;
313 return 0;
314}
315
316int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
317{
318 int result = 0;
319 int throttling_limit;
320 int current_state;
321 struct acpi_processor_limit *limit;
322 int target_state;
323
324 if (ignore_tpc)
325 return 0;
326
327 result = acpi_processor_get_platform_limit(pr);
328 if (result) {
329 /* Throttling Limit is unsupported */
330 return result;
331 }
332
333 throttling_limit = pr->throttling_platform_limit;
334 if (throttling_limit >= pr->throttling.state_count) {
335 /* Uncorrect Throttling Limit */
336 return -EINVAL;
337 }
338
339 current_state = pr->throttling.state;
340 if (current_state > throttling_limit) {
341 /*
342 * The current state can meet the requirement of
343 * _TPC limit. But it is reasonable that OSPM changes
344 * t-states from high to low for better performance.
345 * Of course the limit condition of thermal
346 * and user should be considered.
347 */
348 limit = &pr->limit;
349 target_state = throttling_limit;
350 if (limit->thermal.tx > target_state)
351 target_state = limit->thermal.tx;
352 if (limit->user.tx > target_state)
353 target_state = limit->user.tx;
354 } else if (current_state == throttling_limit) {
355 /*
356 * Unnecessary to change the throttling state
357 */
358 return 0;
359 } else {
360 /*
361 * If the current state is lower than the limit of _TPC, it
362 * will be forced to switch to the throttling state defined
363 * by throttling_platfor_limit.
364 * Because the previous state meets with the limit condition
365 * of thermal and user, it is unnecessary to check it again.
366 */
367 target_state = throttling_limit;
368 }
369 return acpi_processor_set_throttling(pr, target_state, false);
370}
371
372/*
373 * This function is used to reevaluate whether the T-state is valid
374 * after one CPU is onlined/offlined.
375 * It is noted that it won't reevaluate the following properties for
376 * the T-state.
377 * 1. Control method.
378 * 2. the number of supported T-state
379 * 3. TSD domain
380 */
381void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
382 unsigned long action)
383{
384 int result = 0;
385
386 if (action == CPU_DEAD) {
387 /* When one CPU is offline, the T-state throttling
388 * will be invalidated.
389 */
390 pr->flags.throttling = 0;
391 return;
392 }
393 /* the following is to recheck whether the T-state is valid for
394 * the online CPU
395 */
396 if (!pr->throttling.state_count) {
397 /* If the number of T-state is invalid, it is
398 * invalidated.
399 */
400 pr->flags.throttling = 0;
401 return;
402 }
403 pr->flags.throttling = 1;
404
405 /* Disable throttling (if enabled). We'll let subsequent
406 * policy (e.g.thermal) decide to lower performance if it
407 * so chooses, but for now we'll crank up the speed.
408 */
409
410 result = acpi_processor_get_throttling(pr);
411 if (result)
412 goto end;
413
414 if (pr->throttling.state) {
415 result = acpi_processor_set_throttling(pr, 0, false);
416 if (result)
417 goto end;
418 }
419
420end:
421 if (result)
422 pr->flags.throttling = 0;
423}
424/*
425 * _PTC - Processor Throttling Control (and status) register location
426 */
427static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
428{
429 int result = 0;
430 acpi_status status = 0;
431 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
432 union acpi_object *ptc = NULL;
433 union acpi_object obj = { 0 };
434 struct acpi_processor_throttling *throttling;
435
436 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
437 if (ACPI_FAILURE(status)) {
438 if (status != AE_NOT_FOUND) {
439 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
440 }
441 return -ENODEV;
442 }
443
444 ptc = (union acpi_object *)buffer.pointer;
445 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
446 || (ptc->package.count != 2)) {
447 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
448 result = -EFAULT;
449 goto end;
450 }
451
452 /*
453 * control_register
454 */
455
456 obj = ptc->package.elements[0];
457
458 if ((obj.type != ACPI_TYPE_BUFFER)
459 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
460 || (obj.buffer.pointer == NULL)) {
461 printk(KERN_ERR PREFIX
462 "Invalid _PTC data (control_register)\n");
463 result = -EFAULT;
464 goto end;
465 }
466 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
467 sizeof(struct acpi_ptc_register));
468
469 /*
470 * status_register
471 */
472
473 obj = ptc->package.elements[1];
474
475 if ((obj.type != ACPI_TYPE_BUFFER)
476 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
477 || (obj.buffer.pointer == NULL)) {
478 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
479 result = -EFAULT;
480 goto end;
481 }
482
483 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
484 sizeof(struct acpi_ptc_register));
485
486 throttling = &pr->throttling;
487
488 if ((throttling->control_register.bit_width +
489 throttling->control_register.bit_offset) > 32) {
490 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
491 result = -EFAULT;
492 goto end;
493 }
494
495 if ((throttling->status_register.bit_width +
496 throttling->status_register.bit_offset) > 32) {
497 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
498 result = -EFAULT;
499 goto end;
500 }
501
502 end:
503 kfree(buffer.pointer);
504
505 return result;
506}
507
508/*
509 * _TSS - Throttling Supported States
510 */
511static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
512{
513 int result = 0;
514 acpi_status status = AE_OK;
515 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
516 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
517 struct acpi_buffer state = { 0, NULL };
518 union acpi_object *tss = NULL;
519 int i;
520
521 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
522 if (ACPI_FAILURE(status)) {
523 if (status != AE_NOT_FOUND) {
524 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
525 }
526 return -ENODEV;
527 }
528
529 tss = buffer.pointer;
530 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
531 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
532 result = -EFAULT;
533 goto end;
534 }
535
536 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
537 tss->package.count));
538
539 pr->throttling.state_count = tss->package.count;
540 pr->throttling.states_tss =
541 kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
542 GFP_KERNEL);
543 if (!pr->throttling.states_tss) {
544 result = -ENOMEM;
545 goto end;
546 }
547
548 for (i = 0; i < pr->throttling.state_count; i++) {
549
550 struct acpi_processor_tx_tss *tx =
551 (struct acpi_processor_tx_tss *)&(pr->throttling.
552 states_tss[i]);
553
554 state.length = sizeof(struct acpi_processor_tx_tss);
555 state.pointer = tx;
556
557 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
558
559 status = acpi_extract_package(&(tss->package.elements[i]),
560 &format, &state);
561 if (ACPI_FAILURE(status)) {
562 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
563 result = -EFAULT;
564 kfree(pr->throttling.states_tss);
565 goto end;
566 }
567
568 if (!tx->freqpercentage) {
569 printk(KERN_ERR PREFIX
570 "Invalid _TSS data: freq is zero\n");
571 result = -EFAULT;
572 kfree(pr->throttling.states_tss);
573 goto end;
574 }
575 }
576
577 end:
578 kfree(buffer.pointer);
579
580 return result;
581}
582
583/*
584 * _TSD - T-State Dependencies
585 */
586static int acpi_processor_get_tsd(struct acpi_processor *pr)
587{
588 int result = 0;
589 acpi_status status = AE_OK;
590 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
591 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
592 struct acpi_buffer state = { 0, NULL };
593 union acpi_object *tsd = NULL;
594 struct acpi_tsd_package *pdomain;
595 struct acpi_processor_throttling *pthrottling;
596
597 pthrottling = &pr->throttling;
598 pthrottling->tsd_valid_flag = 0;
599
600 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
601 if (ACPI_FAILURE(status)) {
602 if (status != AE_NOT_FOUND) {
603 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
604 }
605 return -ENODEV;
606 }
607
608 tsd = buffer.pointer;
609 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
610 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
611 result = -EFAULT;
612 goto end;
613 }
614
615 if (tsd->package.count != 1) {
616 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
617 result = -EFAULT;
618 goto end;
619 }
620
621 pdomain = &(pr->throttling.domain_info);
622
623 state.length = sizeof(struct acpi_tsd_package);
624 state.pointer = pdomain;
625
626 status = acpi_extract_package(&(tsd->package.elements[0]),
627 &format, &state);
628 if (ACPI_FAILURE(status)) {
629 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
630 result = -EFAULT;
631 goto end;
632 }
633
634 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
635 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
636 result = -EFAULT;
637 goto end;
638 }
639
640 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
641 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
642 result = -EFAULT;
643 goto end;
644 }
645
646 pthrottling = &pr->throttling;
647 pthrottling->tsd_valid_flag = 1;
648 pthrottling->shared_type = pdomain->coord_type;
649 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
650 /*
651 * If the coordination type is not defined in ACPI spec,
652 * the tsd_valid_flag will be clear and coordination type
653 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
654 */
655 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
656 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
657 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
658 pthrottling->tsd_valid_flag = 0;
659 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
660 }
661
662 end:
663 kfree(buffer.pointer);
664 return result;
665}
666
667/* --------------------------------------------------------------------------
668 Throttling Control
669 -------------------------------------------------------------------------- */
670static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
671{
672 int state = 0;
673 u32 value = 0;
674 u32 duty_mask = 0;
675 u32 duty_value = 0;
676
677 if (!pr)
678 return -EINVAL;
679
680 if (!pr->flags.throttling)
681 return -ENODEV;
682
683 pr->throttling.state = 0;
684
685 duty_mask = pr->throttling.state_count - 1;
686
687 duty_mask <<= pr->throttling.duty_offset;
688
689 local_irq_disable();
690
691 value = inl(pr->throttling.address);
692
693 /*
694 * Compute the current throttling state when throttling is enabled
695 * (bit 4 is on).
696 */
697 if (value & 0x10) {
698 duty_value = value & duty_mask;
699 duty_value >>= pr->throttling.duty_offset;
700
701 if (duty_value)
702 state = pr->throttling.state_count - duty_value;
703 }
704
705 pr->throttling.state = state;
706
707 local_irq_enable();
708
709 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
710 "Throttling state is T%d (%d%% throttling applied)\n",
711 state, pr->throttling.states[state].performance));
712
713 return 0;
714}
715
716#ifdef CONFIG_X86
717static int acpi_throttling_rdmsr(u64 *value)
718{
719 u64 msr_high, msr_low;
720 u64 msr = 0;
721 int ret = -1;
722
723 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
724 !this_cpu_has(X86_FEATURE_ACPI)) {
725 printk(KERN_ERR PREFIX
726 "HARDWARE addr space,NOT supported yet\n");
727 } else {
728 msr_low = 0;
729 msr_high = 0;
730 rdmsr_safe(MSR_IA32_THERM_CONTROL,
731 (u32 *)&msr_low , (u32 *) &msr_high);
732 msr = (msr_high << 32) | msr_low;
733 *value = (u64) msr;
734 ret = 0;
735 }
736 return ret;
737}
738
739static int acpi_throttling_wrmsr(u64 value)
740{
741 int ret = -1;
742 u64 msr;
743
744 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
745 !this_cpu_has(X86_FEATURE_ACPI)) {
746 printk(KERN_ERR PREFIX
747 "HARDWARE addr space,NOT supported yet\n");
748 } else {
749 msr = value;
750 wrmsr_safe(MSR_IA32_THERM_CONTROL,
751 msr & 0xffffffff, msr >> 32);
752 ret = 0;
753 }
754 return ret;
755}
756#else
757static int acpi_throttling_rdmsr(u64 *value)
758{
759 printk(KERN_ERR PREFIX
760 "HARDWARE addr space,NOT supported yet\n");
761 return -1;
762}
763
764static int acpi_throttling_wrmsr(u64 value)
765{
766 printk(KERN_ERR PREFIX
767 "HARDWARE addr space,NOT supported yet\n");
768 return -1;
769}
770#endif
771
772static int acpi_read_throttling_status(struct acpi_processor *pr,
773 u64 *value)
774{
775 u32 bit_width, bit_offset;
776 u32 ptc_value;
777 u64 ptc_mask;
778 struct acpi_processor_throttling *throttling;
779 int ret = -1;
780
781 throttling = &pr->throttling;
782 switch (throttling->status_register.space_id) {
783 case ACPI_ADR_SPACE_SYSTEM_IO:
784 bit_width = throttling->status_register.bit_width;
785 bit_offset = throttling->status_register.bit_offset;
786
787 acpi_os_read_port((acpi_io_address) throttling->status_register.
788 address, &ptc_value,
789 (u32) (bit_width + bit_offset));
790 ptc_mask = (1 << bit_width) - 1;
791 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
792 ret = 0;
793 break;
794 case ACPI_ADR_SPACE_FIXED_HARDWARE:
795 ret = acpi_throttling_rdmsr(value);
796 break;
797 default:
798 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
799 (u32) (throttling->status_register.space_id));
800 }
801 return ret;
802}
803
804static int acpi_write_throttling_state(struct acpi_processor *pr,
805 u64 value)
806{
807 u32 bit_width, bit_offset;
808 u64 ptc_value;
809 u64 ptc_mask;
810 struct acpi_processor_throttling *throttling;
811 int ret = -1;
812
813 throttling = &pr->throttling;
814 switch (throttling->control_register.space_id) {
815 case ACPI_ADR_SPACE_SYSTEM_IO:
816 bit_width = throttling->control_register.bit_width;
817 bit_offset = throttling->control_register.bit_offset;
818 ptc_mask = (1 << bit_width) - 1;
819 ptc_value = value & ptc_mask;
820
821 acpi_os_write_port((acpi_io_address) throttling->
822 control_register.address,
823 (u32) (ptc_value << bit_offset),
824 (u32) (bit_width + bit_offset));
825 ret = 0;
826 break;
827 case ACPI_ADR_SPACE_FIXED_HARDWARE:
828 ret = acpi_throttling_wrmsr(value);
829 break;
830 default:
831 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
832 (u32) (throttling->control_register.space_id));
833 }
834 return ret;
835}
836
837static int acpi_get_throttling_state(struct acpi_processor *pr,
838 u64 value)
839{
840 int i;
841
842 for (i = 0; i < pr->throttling.state_count; i++) {
843 struct acpi_processor_tx_tss *tx =
844 (struct acpi_processor_tx_tss *)&(pr->throttling.
845 states_tss[i]);
846 if (tx->control == value)
847 return i;
848 }
849 return -1;
850}
851
852static int acpi_get_throttling_value(struct acpi_processor *pr,
853 int state, u64 *value)
854{
855 int ret = -1;
856
857 if (state >= 0 && state <= pr->throttling.state_count) {
858 struct acpi_processor_tx_tss *tx =
859 (struct acpi_processor_tx_tss *)&(pr->throttling.
860 states_tss[state]);
861 *value = tx->control;
862 ret = 0;
863 }
864 return ret;
865}
866
867static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
868{
869 int state = 0;
870 int ret;
871 u64 value;
872
873 if (!pr)
874 return -EINVAL;
875
876 if (!pr->flags.throttling)
877 return -ENODEV;
878
879 pr->throttling.state = 0;
880
881 value = 0;
882 ret = acpi_read_throttling_status(pr, &value);
883 if (ret >= 0) {
884 state = acpi_get_throttling_state(pr, value);
885 if (state == -1) {
886 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
887 "Invalid throttling state, reset\n"));
888 state = 0;
889 ret = acpi_processor_set_throttling(pr, state, true);
890 if (ret)
891 return ret;
892 }
893 pr->throttling.state = state;
894 }
895
896 return 0;
897}
898
899static int acpi_processor_get_throttling(struct acpi_processor *pr)
900{
901 cpumask_var_t saved_mask;
902 int ret;
903
904 if (!pr)
905 return -EINVAL;
906
907 if (!pr->flags.throttling)
908 return -ENODEV;
909
910 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
911 return -ENOMEM;
912
913 /*
914 * Migrate task to the cpu pointed by pr.
915 */
916 cpumask_copy(saved_mask, ¤t->cpus_allowed);
917 /* FIXME: use work_on_cpu() */
918 if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) {
919 /* Can't migrate to the target pr->id CPU. Exit */
920 free_cpumask_var(saved_mask);
921 return -ENODEV;
922 }
923 ret = pr->throttling.acpi_processor_get_throttling(pr);
924 /* restore the previous state */
925 set_cpus_allowed_ptr(current, saved_mask);
926 free_cpumask_var(saved_mask);
927
928 return ret;
929}
930
931static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
932{
933 int i, step;
934
935 if (!pr->throttling.address) {
936 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
937 return -EINVAL;
938 } else if (!pr->throttling.duty_width) {
939 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
940 return -EINVAL;
941 }
942 /* TBD: Support duty_cycle values that span bit 4. */
943 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
944 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
945 return -EINVAL;
946 }
947
948 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
949
950 /*
951 * Compute state values. Note that throttling displays a linear power
952 * performance relationship (at 50% performance the CPU will consume
953 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
954 */
955
956 step = (1000 / pr->throttling.state_count);
957
958 for (i = 0; i < pr->throttling.state_count; i++) {
959 pr->throttling.states[i].performance = 1000 - step * i;
960 pr->throttling.states[i].power = 1000 - step * i;
961 }
962 return 0;
963}
964
965static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
966 int state, bool force)
967{
968 u32 value = 0;
969 u32 duty_mask = 0;
970 u32 duty_value = 0;
971
972 if (!pr)
973 return -EINVAL;
974
975 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
976 return -EINVAL;
977
978 if (!pr->flags.throttling)
979 return -ENODEV;
980
981 if (!force && (state == pr->throttling.state))
982 return 0;
983
984 if (state < pr->throttling_platform_limit)
985 return -EPERM;
986 /*
987 * Calculate the duty_value and duty_mask.
988 */
989 if (state) {
990 duty_value = pr->throttling.state_count - state;
991
992 duty_value <<= pr->throttling.duty_offset;
993
994 /* Used to clear all duty_value bits */
995 duty_mask = pr->throttling.state_count - 1;
996
997 duty_mask <<= acpi_gbl_FADT.duty_offset;
998 duty_mask = ~duty_mask;
999 }
1000
1001 local_irq_disable();
1002
1003 /*
1004 * Disable throttling by writing a 0 to bit 4. Note that we must
1005 * turn it off before you can change the duty_value.
1006 */
1007 value = inl(pr->throttling.address);
1008 if (value & 0x10) {
1009 value &= 0xFFFFFFEF;
1010 outl(value, pr->throttling.address);
1011 }
1012
1013 /*
1014 * Write the new duty_value and then enable throttling. Note
1015 * that a state value of 0 leaves throttling disabled.
1016 */
1017 if (state) {
1018 value &= duty_mask;
1019 value |= duty_value;
1020 outl(value, pr->throttling.address);
1021
1022 value |= 0x00000010;
1023 outl(value, pr->throttling.address);
1024 }
1025
1026 pr->throttling.state = state;
1027
1028 local_irq_enable();
1029
1030 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1031 "Throttling state set to T%d (%d%%)\n", state,
1032 (pr->throttling.states[state].performance ? pr->
1033 throttling.states[state].performance / 10 : 0)));
1034
1035 return 0;
1036}
1037
1038static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1039 int state, bool force)
1040{
1041 int ret;
1042 u64 value;
1043
1044 if (!pr)
1045 return -EINVAL;
1046
1047 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1048 return -EINVAL;
1049
1050 if (!pr->flags.throttling)
1051 return -ENODEV;
1052
1053 if (!force && (state == pr->throttling.state))
1054 return 0;
1055
1056 if (state < pr->throttling_platform_limit)
1057 return -EPERM;
1058
1059 value = 0;
1060 ret = acpi_get_throttling_value(pr, state, &value);
1061 if (ret >= 0) {
1062 acpi_write_throttling_state(pr, value);
1063 pr->throttling.state = state;
1064 }
1065
1066 return 0;
1067}
1068
1069static long acpi_processor_throttling_fn(void *data)
1070{
1071 struct acpi_processor_throttling_arg *arg = data;
1072 struct acpi_processor *pr = arg->pr;
1073
1074 return pr->throttling.acpi_processor_set_throttling(pr,
1075 arg->target_state, arg->force);
1076}
1077
1078int acpi_processor_set_throttling(struct acpi_processor *pr,
1079 int state, bool force)
1080{
1081 int ret = 0;
1082 unsigned int i;
1083 struct acpi_processor *match_pr;
1084 struct acpi_processor_throttling *p_throttling;
1085 struct acpi_processor_throttling_arg arg;
1086 struct throttling_tstate t_state;
1087
1088 if (!pr)
1089 return -EINVAL;
1090
1091 if (!pr->flags.throttling)
1092 return -ENODEV;
1093
1094 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1095 return -EINVAL;
1096
1097 if (cpu_is_offline(pr->id)) {
1098 /*
1099 * the cpu pointed by pr->id is offline. Unnecessary to change
1100 * the throttling state any more.
1101 */
1102 return -ENODEV;
1103 }
1104
1105 t_state.target_state = state;
1106 p_throttling = &(pr->throttling);
1107
1108 /*
1109 * The throttling notifier will be called for every
1110 * affected cpu in order to get one proper T-state.
1111 * The notifier event is THROTTLING_PRECHANGE.
1112 */
1113 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1114 t_state.cpu = i;
1115 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1116 &t_state);
1117 }
1118 /*
1119 * The function of acpi_processor_set_throttling will be called
1120 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1121 * it is necessary to call it for every affected cpu. Otherwise
1122 * it can be called only for the cpu pointed by pr.
1123 */
1124 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1125 arg.pr = pr;
1126 arg.target_state = state;
1127 arg.force = force;
1128 ret = work_on_cpu(pr->id, acpi_processor_throttling_fn, &arg);
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_and(i, cpu_online_mask,
1136 p_throttling->shared_cpu_map) {
1137 match_pr = per_cpu(processors, i);
1138 /*
1139 * If the pointer is invalid, we will report the
1140 * error message and continue.
1141 */
1142 if (!match_pr) {
1143 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1144 "Invalid Pointer for CPU %d\n", i));
1145 continue;
1146 }
1147 /*
1148 * If the throttling control is unsupported on CPU i,
1149 * we will report the error message and continue.
1150 */
1151 if (!match_pr->flags.throttling) {
1152 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1153 "Throttling Control is unsupported "
1154 "on CPU %d\n", i));
1155 continue;
1156 }
1157
1158 arg.pr = match_pr;
1159 arg.target_state = state;
1160 arg.force = force;
1161 ret = work_on_cpu(pr->id, acpi_processor_throttling_fn,
1162 &arg);
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_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1172 t_state.cpu = i;
1173 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1174 &t_state);
1175 }
1176
1177 return ret;
1178}
1179
1180int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1181{
1182 int result = 0;
1183 struct acpi_processor_throttling *pthrottling;
1184
1185 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1186 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1187 pr->throttling.address,
1188 pr->throttling.duty_offset,
1189 pr->throttling.duty_width));
1190
1191 /*
1192 * Evaluate _PTC, _TSS and _TPC
1193 * They must all be present or none of them can be used.
1194 */
1195 if (acpi_processor_get_throttling_control(pr) ||
1196 acpi_processor_get_throttling_states(pr) ||
1197 acpi_processor_get_platform_limit(pr))
1198 {
1199 pr->throttling.acpi_processor_get_throttling =
1200 &acpi_processor_get_throttling_fadt;
1201 pr->throttling.acpi_processor_set_throttling =
1202 &acpi_processor_set_throttling_fadt;
1203 if (acpi_processor_get_fadt_info(pr))
1204 return 0;
1205 } else {
1206 pr->throttling.acpi_processor_get_throttling =
1207 &acpi_processor_get_throttling_ptc;
1208 pr->throttling.acpi_processor_set_throttling =
1209 &acpi_processor_set_throttling_ptc;
1210 }
1211
1212 /*
1213 * If TSD package for one CPU can't be parsed successfully, it means
1214 * that this CPU will have no coordination with other CPUs.
1215 */
1216 if (acpi_processor_get_tsd(pr)) {
1217 pthrottling = &pr->throttling;
1218 pthrottling->tsd_valid_flag = 0;
1219 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1220 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1221 }
1222
1223 /*
1224 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1225 * This shouldn't be an issue as few (if any) mobile systems ever
1226 * used this part.
1227 */
1228 if (errata.piix4.throttle) {
1229 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1230 "Throttling not supported on PIIX4 A- or B-step\n"));
1231 return 0;
1232 }
1233
1234 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1235 pr->throttling.state_count));
1236
1237 pr->flags.throttling = 1;
1238
1239 /*
1240 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1241 * thermal) decide to lower performance if it so chooses, but for now
1242 * we'll crank up the speed.
1243 */
1244
1245 result = acpi_processor_get_throttling(pr);
1246 if (result)
1247 goto end;
1248
1249 if (pr->throttling.state) {
1250 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1251 "Disabling throttling (was T%d)\n",
1252 pr->throttling.state));
1253 result = acpi_processor_set_throttling(pr, 0, false);
1254 if (result)
1255 goto end;
1256 }
1257
1258 end:
1259 if (result)
1260 pr->flags.throttling = 0;
1261
1262 return result;
1263}
1264