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