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