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