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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#define pr_fmt(fmt) "ACPI: " fmt
13
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/slab.h>
17#include <linux/init.h>
18#include <linux/sched.h>
19#include <linux/cpufreq.h>
20#include <linux/acpi.h>
21#include <acpi/processor.h>
22#include <asm/io.h>
23#include <linux/uaccess.h>
24
25/* ignore_tpc:
26 * 0 -> acpi processor driver doesn't ignore _TPC values
27 * 1 -> acpi processor driver ignores _TPC values
28 */
29static int ignore_tpc;
30module_param(ignore_tpc, int, 0644);
31MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
32
33struct throttling_tstate {
34 unsigned int cpu; /* cpu nr */
35 int target_state; /* target T-state */
36};
37
38struct acpi_processor_throttling_arg {
39 struct acpi_processor *pr;
40 int target_state;
41 bool force;
42};
43
44#define THROTTLING_PRECHANGE (1)
45#define THROTTLING_POSTCHANGE (2)
46
47static int acpi_processor_get_throttling(struct acpi_processor *pr);
48static int __acpi_processor_set_throttling(struct acpi_processor *pr,
49 int state, bool force, bool direct);
50
51static int acpi_processor_update_tsd_coord(void)
52{
53 int count_target;
54 int retval = 0;
55 unsigned int i, j;
56 cpumask_var_t covered_cpus;
57 struct acpi_processor *pr, *match_pr;
58 struct acpi_tsd_package *pdomain, *match_pdomain;
59 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
60
61 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
62 return -ENOMEM;
63
64 /*
65 * Now that we have _TSD data from all CPUs, lets setup T-state
66 * coordination between all CPUs.
67 */
68 for_each_possible_cpu(i) {
69 pr = per_cpu(processors, i);
70 if (!pr)
71 continue;
72
73 /* Basic validity check for domain info */
74 pthrottling = &(pr->throttling);
75
76 /*
77 * If tsd package for one cpu is invalid, the coordination
78 * among all CPUs is thought as invalid.
79 * Maybe it is ugly.
80 */
81 if (!pthrottling->tsd_valid_flag) {
82 retval = -EINVAL;
83 break;
84 }
85 }
86 if (retval)
87 goto err_ret;
88
89 for_each_possible_cpu(i) {
90 pr = per_cpu(processors, i);
91 if (!pr)
92 continue;
93
94 if (cpumask_test_cpu(i, covered_cpus))
95 continue;
96 pthrottling = &pr->throttling;
97
98 pdomain = &(pthrottling->domain_info);
99 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
100 cpumask_set_cpu(i, covered_cpus);
101 /*
102 * If the number of processor in the TSD domain is 1, it is
103 * unnecessary to parse the coordination for this CPU.
104 */
105 if (pdomain->num_processors <= 1)
106 continue;
107
108 /* Validate the Domain info */
109 count_target = pdomain->num_processors;
110
111 for_each_possible_cpu(j) {
112 if (i == j)
113 continue;
114
115 match_pr = per_cpu(processors, j);
116 if (!match_pr)
117 continue;
118
119 match_pthrottling = &(match_pr->throttling);
120 match_pdomain = &(match_pthrottling->domain_info);
121 if (match_pdomain->domain != pdomain->domain)
122 continue;
123
124 /* Here i and j are in the same domain.
125 * If two TSD packages have the same domain, they
126 * should have the same num_porcessors and
127 * coordination type. Otherwise it will be regarded
128 * as illegal.
129 */
130 if (match_pdomain->num_processors != count_target) {
131 retval = -EINVAL;
132 goto err_ret;
133 }
134
135 if (pdomain->coord_type != match_pdomain->coord_type) {
136 retval = -EINVAL;
137 goto err_ret;
138 }
139
140 cpumask_set_cpu(j, covered_cpus);
141 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
142 }
143 for_each_possible_cpu(j) {
144 if (i == j)
145 continue;
146
147 match_pr = per_cpu(processors, j);
148 if (!match_pr)
149 continue;
150
151 match_pthrottling = &(match_pr->throttling);
152 match_pdomain = &(match_pthrottling->domain_info);
153 if (match_pdomain->domain != pdomain->domain)
154 continue;
155
156 /*
157 * If some CPUS have the same domain, they
158 * will have the same shared_cpu_map.
159 */
160 cpumask_copy(match_pthrottling->shared_cpu_map,
161 pthrottling->shared_cpu_map);
162 }
163 }
164
165err_ret:
166 free_cpumask_var(covered_cpus);
167
168 for_each_possible_cpu(i) {
169 pr = per_cpu(processors, i);
170 if (!pr)
171 continue;
172
173 /*
174 * Assume no coordination on any error parsing domain info.
175 * The coordination type will be forced as SW_ALL.
176 */
177 if (retval) {
178 pthrottling = &(pr->throttling);
179 cpumask_clear(pthrottling->shared_cpu_map);
180 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
181 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
182 }
183 }
184
185 return retval;
186}
187
188/*
189 * Update the T-state coordination after the _TSD
190 * data for all cpus is obtained.
191 */
192void acpi_processor_throttling_init(void)
193{
194 if (acpi_processor_update_tsd_coord())
195 pr_debug("Assume no T-state coordination\n");
196}
197
198static int acpi_processor_throttling_notifier(unsigned long event, void *data)
199{
200 struct throttling_tstate *p_tstate = data;
201 struct acpi_processor *pr;
202 unsigned int cpu;
203 int target_state;
204 struct acpi_processor_limit *p_limit;
205 struct acpi_processor_throttling *p_throttling;
206
207 cpu = p_tstate->cpu;
208 pr = per_cpu(processors, cpu);
209 if (!pr) {
210 pr_debug("Invalid pr pointer\n");
211 return 0;
212 }
213 if (!pr->flags.throttling) {
214 acpi_handle_debug(pr->handle,
215 "Throttling control unsupported on CPU %d\n",
216 cpu);
217 return 0;
218 }
219 target_state = p_tstate->target_state;
220 p_throttling = &(pr->throttling);
221 switch (event) {
222 case THROTTLING_PRECHANGE:
223 /*
224 * Prechange event is used to choose one proper t-state,
225 * which meets the limits of thermal, user and _TPC.
226 */
227 p_limit = &pr->limit;
228 if (p_limit->thermal.tx > target_state)
229 target_state = p_limit->thermal.tx;
230 if (p_limit->user.tx > target_state)
231 target_state = p_limit->user.tx;
232 if (pr->throttling_platform_limit > target_state)
233 target_state = pr->throttling_platform_limit;
234 if (target_state >= p_throttling->state_count) {
235 pr_warn("Exceed the limit of T-state \n");
236 target_state = p_throttling->state_count - 1;
237 }
238 p_tstate->target_state = target_state;
239 acpi_handle_debug(pr->handle,
240 "PreChange Event: target T-state of CPU %d is T%d\n",
241 cpu, target_state);
242 break;
243 case THROTTLING_POSTCHANGE:
244 /*
245 * Postchange event is only used to update the
246 * T-state flag of acpi_processor_throttling.
247 */
248 p_throttling->state = target_state;
249 acpi_handle_debug(pr->handle,
250 "PostChange Event: CPU %d is switched to T%d\n",
251 cpu, target_state);
252 break;
253 default:
254 pr_warn("Unsupported Throttling notifier event\n");
255 break;
256 }
257
258 return 0;
259}
260
261/*
262 * _TPC - Throttling Present Capabilities
263 */
264static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
265{
266 acpi_status status = 0;
267 unsigned long long tpc = 0;
268
269 if (!pr)
270 return -EINVAL;
271
272 if (ignore_tpc)
273 goto end;
274
275 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
276 if (ACPI_FAILURE(status)) {
277 if (status != AE_NOT_FOUND)
278 acpi_evaluation_failure_warn(pr->handle, "_TPC", status);
279
280 return -ENODEV;
281 }
282
283end:
284 pr->throttling_platform_limit = (int)tpc;
285 return 0;
286}
287
288int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
289{
290 int result = 0;
291 int throttling_limit;
292 int current_state;
293 struct acpi_processor_limit *limit;
294 int target_state;
295
296 if (ignore_tpc)
297 return 0;
298
299 result = acpi_processor_get_platform_limit(pr);
300 if (result) {
301 /* Throttling Limit is unsupported */
302 return result;
303 }
304
305 throttling_limit = pr->throttling_platform_limit;
306 if (throttling_limit >= pr->throttling.state_count) {
307 /* Uncorrect Throttling Limit */
308 return -EINVAL;
309 }
310
311 current_state = pr->throttling.state;
312 if (current_state > throttling_limit) {
313 /*
314 * The current state can meet the requirement of
315 * _TPC limit. But it is reasonable that OSPM changes
316 * t-states from high to low for better performance.
317 * Of course the limit condition of thermal
318 * and user should be considered.
319 */
320 limit = &pr->limit;
321 target_state = throttling_limit;
322 if (limit->thermal.tx > target_state)
323 target_state = limit->thermal.tx;
324 if (limit->user.tx > target_state)
325 target_state = limit->user.tx;
326 } else if (current_state == throttling_limit) {
327 /*
328 * Unnecessary to change the throttling state
329 */
330 return 0;
331 } else {
332 /*
333 * If the current state is lower than the limit of _TPC, it
334 * will be forced to switch to the throttling state defined
335 * by throttling_platfor_limit.
336 * Because the previous state meets with the limit condition
337 * of thermal and user, it is unnecessary to check it again.
338 */
339 target_state = throttling_limit;
340 }
341 return acpi_processor_set_throttling(pr, target_state, false);
342}
343
344/*
345 * This function is used to reevaluate whether the T-state is valid
346 * after one CPU is onlined/offlined.
347 * It is noted that it won't reevaluate the following properties for
348 * the T-state.
349 * 1. Control method.
350 * 2. the number of supported T-state
351 * 3. TSD domain
352 */
353void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
354 bool is_dead)
355{
356 int result = 0;
357
358 if (is_dead) {
359 /* When one CPU is offline, the T-state throttling
360 * will be invalidated.
361 */
362 pr->flags.throttling = 0;
363 return;
364 }
365 /* the following is to recheck whether the T-state is valid for
366 * the online CPU
367 */
368 if (!pr->throttling.state_count) {
369 /* If the number of T-state is invalid, it is
370 * invalidated.
371 */
372 pr->flags.throttling = 0;
373 return;
374 }
375 pr->flags.throttling = 1;
376
377 /* Disable throttling (if enabled). We'll let subsequent
378 * policy (e.g.thermal) decide to lower performance if it
379 * so chooses, but for now we'll crank up the speed.
380 */
381
382 result = acpi_processor_get_throttling(pr);
383 if (result)
384 goto end;
385
386 if (pr->throttling.state) {
387 result = acpi_processor_set_throttling(pr, 0, false);
388 if (result)
389 goto end;
390 }
391
392end:
393 if (result)
394 pr->flags.throttling = 0;
395}
396/*
397 * _PTC - Processor Throttling Control (and status) register location
398 */
399static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
400{
401 int result = 0;
402 acpi_status status = 0;
403 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
404 union acpi_object *ptc = NULL;
405 union acpi_object obj;
406 struct acpi_processor_throttling *throttling;
407
408 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
409 if (ACPI_FAILURE(status)) {
410 if (status != AE_NOT_FOUND)
411 acpi_evaluation_failure_warn(pr->handle, "_PTC", status);
412
413 return -ENODEV;
414 }
415
416 ptc = (union acpi_object *)buffer.pointer;
417 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
418 || (ptc->package.count != 2)) {
419 pr_err("Invalid _PTC data\n");
420 result = -EFAULT;
421 goto end;
422 }
423
424 /*
425 * control_register
426 */
427
428 obj = ptc->package.elements[0];
429
430 if ((obj.type != ACPI_TYPE_BUFFER)
431 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
432 || (obj.buffer.pointer == NULL)) {
433 pr_err("Invalid _PTC data (control_register)\n");
434 result = -EFAULT;
435 goto end;
436 }
437 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
438 sizeof(struct acpi_ptc_register));
439
440 /*
441 * status_register
442 */
443
444 obj = ptc->package.elements[1];
445
446 if ((obj.type != ACPI_TYPE_BUFFER)
447 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
448 || (obj.buffer.pointer == NULL)) {
449 pr_err("Invalid _PTC data (status_register)\n");
450 result = -EFAULT;
451 goto end;
452 }
453
454 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
455 sizeof(struct acpi_ptc_register));
456
457 throttling = &pr->throttling;
458
459 if ((throttling->control_register.bit_width +
460 throttling->control_register.bit_offset) > 32) {
461 pr_err("Invalid _PTC control register\n");
462 result = -EFAULT;
463 goto end;
464 }
465
466 if ((throttling->status_register.bit_width +
467 throttling->status_register.bit_offset) > 32) {
468 pr_err("Invalid _PTC status register\n");
469 result = -EFAULT;
470 goto end;
471 }
472
473end:
474 kfree(buffer.pointer);
475
476 return result;
477}
478
479/*
480 * _TSS - Throttling Supported States
481 */
482static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
483{
484 int result = 0;
485 acpi_status status = AE_OK;
486 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
487 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
488 struct acpi_buffer state = { 0, NULL };
489 union acpi_object *tss = NULL;
490 int i;
491
492 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
493 if (ACPI_FAILURE(status)) {
494 if (status != AE_NOT_FOUND)
495 acpi_evaluation_failure_warn(pr->handle, "_TSS", status);
496
497 return -ENODEV;
498 }
499
500 tss = buffer.pointer;
501 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
502 pr_err("Invalid _TSS data\n");
503 result = -EFAULT;
504 goto end;
505 }
506
507 acpi_handle_debug(pr->handle, "Found %d throttling states\n",
508 tss->package.count);
509
510 pr->throttling.state_count = tss->package.count;
511 pr->throttling.states_tss =
512 kmalloc_array(tss->package.count,
513 sizeof(struct acpi_processor_tx_tss),
514 GFP_KERNEL);
515 if (!pr->throttling.states_tss) {
516 result = -ENOMEM;
517 goto end;
518 }
519
520 for (i = 0; i < pr->throttling.state_count; i++) {
521
522 struct acpi_processor_tx_tss *tx =
523 (struct acpi_processor_tx_tss *)&(pr->throttling.
524 states_tss[i]);
525
526 state.length = sizeof(struct acpi_processor_tx_tss);
527 state.pointer = tx;
528
529 acpi_handle_debug(pr->handle, "Extracting state %d\n", i);
530
531 status = acpi_extract_package(&(tss->package.elements[i]),
532 &format, &state);
533 if (ACPI_FAILURE(status)) {
534 acpi_handle_warn(pr->handle, "Invalid _TSS data: %s\n",
535 acpi_format_exception(status));
536 result = -EFAULT;
537 kfree(pr->throttling.states_tss);
538 goto end;
539 }
540
541 if (!tx->freqpercentage) {
542 pr_err("Invalid _TSS data: freq is zero\n");
543 result = -EFAULT;
544 kfree(pr->throttling.states_tss);
545 goto end;
546 }
547 }
548
549end:
550 kfree(buffer.pointer);
551
552 return result;
553}
554
555/*
556 * _TSD - T-State Dependencies
557 */
558static int acpi_processor_get_tsd(struct acpi_processor *pr)
559{
560 int result = 0;
561 acpi_status status = AE_OK;
562 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
563 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
564 struct acpi_buffer state = { 0, NULL };
565 union acpi_object *tsd = NULL;
566 struct acpi_tsd_package *pdomain;
567 struct acpi_processor_throttling *pthrottling;
568
569 pthrottling = &pr->throttling;
570 pthrottling->tsd_valid_flag = 0;
571
572 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
573 if (ACPI_FAILURE(status)) {
574 if (status != AE_NOT_FOUND)
575 acpi_evaluation_failure_warn(pr->handle, "_TSD", status);
576
577 return -ENODEV;
578 }
579
580 tsd = buffer.pointer;
581 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
582 pr_err("Invalid _TSD data\n");
583 result = -EFAULT;
584 goto end;
585 }
586
587 if (tsd->package.count != 1) {
588 pr_err("Invalid _TSD data\n");
589 result = -EFAULT;
590 goto end;
591 }
592
593 pdomain = &(pr->throttling.domain_info);
594
595 state.length = sizeof(struct acpi_tsd_package);
596 state.pointer = pdomain;
597
598 status = acpi_extract_package(&(tsd->package.elements[0]),
599 &format, &state);
600 if (ACPI_FAILURE(status)) {
601 pr_err("Invalid _TSD data\n");
602 result = -EFAULT;
603 goto end;
604 }
605
606 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
607 pr_err("Unknown _TSD:num_entries\n");
608 result = -EFAULT;
609 goto end;
610 }
611
612 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
613 pr_err("Unknown _TSD:revision\n");
614 result = -EFAULT;
615 goto end;
616 }
617
618 pthrottling = &pr->throttling;
619 pthrottling->tsd_valid_flag = 1;
620 pthrottling->shared_type = pdomain->coord_type;
621 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
622 /*
623 * If the coordination type is not defined in ACPI spec,
624 * the tsd_valid_flag will be clear and coordination type
625 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
626 */
627 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
628 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
629 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
630 pthrottling->tsd_valid_flag = 0;
631 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
632 }
633
634end:
635 kfree(buffer.pointer);
636 return result;
637}
638
639/* --------------------------------------------------------------------------
640 Throttling Control
641 -------------------------------------------------------------------------- */
642static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
643{
644 int state = 0;
645 u32 value = 0;
646 u32 duty_mask = 0;
647 u32 duty_value = 0;
648
649 if (!pr)
650 return -EINVAL;
651
652 if (!pr->flags.throttling)
653 return -ENODEV;
654
655 /*
656 * We don't care about error returns - we just try to mark
657 * these reserved so that nobody else is confused into thinking
658 * that this region might be unused..
659 *
660 * (In particular, allocating the IO range for Cardbus)
661 */
662 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
663
664 pr->throttling.state = 0;
665
666 duty_mask = pr->throttling.state_count - 1;
667
668 duty_mask <<= pr->throttling.duty_offset;
669
670 local_irq_disable();
671
672 value = inl(pr->throttling.address);
673
674 /*
675 * Compute the current throttling state when throttling is enabled
676 * (bit 4 is on).
677 */
678 if (value & 0x10) {
679 duty_value = value & duty_mask;
680 duty_value >>= pr->throttling.duty_offset;
681
682 if (duty_value)
683 state = pr->throttling.state_count - duty_value;
684 }
685
686 pr->throttling.state = state;
687
688 local_irq_enable();
689
690 acpi_handle_debug(pr->handle,
691 "Throttling state is T%d (%d%% throttling applied)\n",
692 state, pr->throttling.states[state].performance);
693
694 return 0;
695}
696
697#ifdef CONFIG_X86
698static int acpi_throttling_rdmsr(u64 *value)
699{
700 u64 msr_high, msr_low;
701 u64 msr = 0;
702 int ret = -1;
703
704 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
705 !this_cpu_has(X86_FEATURE_ACPI)) {
706 pr_err("HARDWARE addr space,NOT supported yet\n");
707 } else {
708 msr_low = 0;
709 msr_high = 0;
710 rdmsr_safe(MSR_IA32_THERM_CONTROL,
711 (u32 *)&msr_low, (u32 *) &msr_high);
712 msr = (msr_high << 32) | msr_low;
713 *value = (u64) msr;
714 ret = 0;
715 }
716 return ret;
717}
718
719static int acpi_throttling_wrmsr(u64 value)
720{
721 int ret = -1;
722 u64 msr;
723
724 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
725 !this_cpu_has(X86_FEATURE_ACPI)) {
726 pr_err("HARDWARE addr space,NOT supported yet\n");
727 } else {
728 msr = value;
729 wrmsr_safe(MSR_IA32_THERM_CONTROL,
730 msr & 0xffffffff, msr >> 32);
731 ret = 0;
732 }
733 return ret;
734}
735#else
736static int acpi_throttling_rdmsr(u64 *value)
737{
738 pr_err("HARDWARE addr space,NOT supported yet\n");
739 return -1;
740}
741
742static int acpi_throttling_wrmsr(u64 value)
743{
744 pr_err("HARDWARE addr space,NOT supported yet\n");
745 return -1;
746}
747#endif
748
749static int acpi_read_throttling_status(struct acpi_processor *pr,
750 u64 *value)
751{
752 u32 bit_width, bit_offset;
753 u32 ptc_value;
754 u64 ptc_mask;
755 struct acpi_processor_throttling *throttling;
756 int ret = -1;
757
758 throttling = &pr->throttling;
759 switch (throttling->status_register.space_id) {
760 case ACPI_ADR_SPACE_SYSTEM_IO:
761 bit_width = throttling->status_register.bit_width;
762 bit_offset = throttling->status_register.bit_offset;
763
764 acpi_os_read_port((acpi_io_address) throttling->status_register.
765 address, &ptc_value,
766 (u32) (bit_width + bit_offset));
767 ptc_mask = (1 << bit_width) - 1;
768 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
769 ret = 0;
770 break;
771 case ACPI_ADR_SPACE_FIXED_HARDWARE:
772 ret = acpi_throttling_rdmsr(value);
773 break;
774 default:
775 pr_err("Unknown addr space %d\n",
776 (u32) (throttling->status_register.space_id));
777 }
778 return ret;
779}
780
781static int acpi_write_throttling_state(struct acpi_processor *pr,
782 u64 value)
783{
784 u32 bit_width, bit_offset;
785 u64 ptc_value;
786 u64 ptc_mask;
787 struct acpi_processor_throttling *throttling;
788 int ret = -1;
789
790 throttling = &pr->throttling;
791 switch (throttling->control_register.space_id) {
792 case ACPI_ADR_SPACE_SYSTEM_IO:
793 bit_width = throttling->control_register.bit_width;
794 bit_offset = throttling->control_register.bit_offset;
795 ptc_mask = (1 << bit_width) - 1;
796 ptc_value = value & ptc_mask;
797
798 acpi_os_write_port((acpi_io_address) throttling->
799 control_register.address,
800 (u32) (ptc_value << bit_offset),
801 (u32) (bit_width + bit_offset));
802 ret = 0;
803 break;
804 case ACPI_ADR_SPACE_FIXED_HARDWARE:
805 ret = acpi_throttling_wrmsr(value);
806 break;
807 default:
808 pr_err("Unknown addr space %d\n",
809 (u32) (throttling->control_register.space_id));
810 }
811 return ret;
812}
813
814static int acpi_get_throttling_state(struct acpi_processor *pr,
815 u64 value)
816{
817 int i;
818
819 for (i = 0; i < pr->throttling.state_count; i++) {
820 struct acpi_processor_tx_tss *tx =
821 (struct acpi_processor_tx_tss *)&(pr->throttling.
822 states_tss[i]);
823 if (tx->control == value)
824 return i;
825 }
826 return -1;
827}
828
829static int acpi_get_throttling_value(struct acpi_processor *pr,
830 int state, u64 *value)
831{
832 int ret = -1;
833
834 if (state >= 0 && state <= pr->throttling.state_count) {
835 struct acpi_processor_tx_tss *tx =
836 (struct acpi_processor_tx_tss *)&(pr->throttling.
837 states_tss[state]);
838 *value = tx->control;
839 ret = 0;
840 }
841 return ret;
842}
843
844static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
845{
846 int state = 0;
847 int ret;
848 u64 value;
849
850 if (!pr)
851 return -EINVAL;
852
853 if (!pr->flags.throttling)
854 return -ENODEV;
855
856 pr->throttling.state = 0;
857
858 value = 0;
859 ret = acpi_read_throttling_status(pr, &value);
860 if (ret >= 0) {
861 state = acpi_get_throttling_state(pr, value);
862 if (state == -1) {
863 acpi_handle_debug(pr->handle,
864 "Invalid throttling state, reset\n");
865 state = 0;
866 ret = __acpi_processor_set_throttling(pr, state, true,
867 true);
868 if (ret)
869 return ret;
870 }
871 pr->throttling.state = state;
872 }
873
874 return 0;
875}
876
877static long __acpi_processor_get_throttling(void *data)
878{
879 struct acpi_processor *pr = data;
880
881 return pr->throttling.acpi_processor_get_throttling(pr);
882}
883
884static int acpi_processor_get_throttling(struct acpi_processor *pr)
885{
886 if (!pr)
887 return -EINVAL;
888
889 if (!pr->flags.throttling)
890 return -ENODEV;
891
892 /*
893 * This is either called from the CPU hotplug callback of
894 * processor_driver or via the ACPI probe function. In the latter
895 * case the CPU is not guaranteed to be online. Both call sites are
896 * protected against CPU hotplug.
897 */
898 if (!cpu_online(pr->id))
899 return -ENODEV;
900
901 return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false);
902}
903
904static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
905{
906 int i, step;
907
908 if (!pr->throttling.address) {
909 acpi_handle_debug(pr->handle, "No throttling register\n");
910 return -EINVAL;
911 } else if (!pr->throttling.duty_width) {
912 acpi_handle_debug(pr->handle, "No throttling states\n");
913 return -EINVAL;
914 }
915 /* TBD: Support duty_cycle values that span bit 4. */
916 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
917 pr_warn("duty_cycle spans bit 4\n");
918 return -EINVAL;
919 }
920
921 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
922
923 /*
924 * Compute state values. Note that throttling displays a linear power
925 * performance relationship (at 50% performance the CPU will consume
926 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
927 */
928
929 step = (1000 / pr->throttling.state_count);
930
931 for (i = 0; i < pr->throttling.state_count; i++) {
932 pr->throttling.states[i].performance = 1000 - step * i;
933 pr->throttling.states[i].power = 1000 - step * i;
934 }
935 return 0;
936}
937
938static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
939 int state, bool force)
940{
941 u32 value = 0;
942 u32 duty_mask = 0;
943 u32 duty_value = 0;
944
945 if (!pr)
946 return -EINVAL;
947
948 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
949 return -EINVAL;
950
951 if (!pr->flags.throttling)
952 return -ENODEV;
953
954 if (!force && (state == pr->throttling.state))
955 return 0;
956
957 if (state < pr->throttling_platform_limit)
958 return -EPERM;
959 /*
960 * Calculate the duty_value and duty_mask.
961 */
962 if (state) {
963 duty_value = pr->throttling.state_count - state;
964
965 duty_value <<= pr->throttling.duty_offset;
966
967 /* Used to clear all duty_value bits */
968 duty_mask = pr->throttling.state_count - 1;
969
970 duty_mask <<= acpi_gbl_FADT.duty_offset;
971 duty_mask = ~duty_mask;
972 }
973
974 local_irq_disable();
975
976 /*
977 * Disable throttling by writing a 0 to bit 4. Note that we must
978 * turn it off before you can change the duty_value.
979 */
980 value = inl(pr->throttling.address);
981 if (value & 0x10) {
982 value &= 0xFFFFFFEF;
983 outl(value, pr->throttling.address);
984 }
985
986 /*
987 * Write the new duty_value and then enable throttling. Note
988 * that a state value of 0 leaves throttling disabled.
989 */
990 if (state) {
991 value &= duty_mask;
992 value |= duty_value;
993 outl(value, pr->throttling.address);
994
995 value |= 0x00000010;
996 outl(value, pr->throttling.address);
997 }
998
999 pr->throttling.state = state;
1000
1001 local_irq_enable();
1002
1003 acpi_handle_debug(pr->handle,
1004 "Throttling state set to T%d (%d%%)\n", state,
1005 (pr->throttling.states[state].performance ? pr->
1006 throttling.states[state].performance / 10 : 0));
1007
1008 return 0;
1009}
1010
1011static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1012 int state, bool force)
1013{
1014 int ret;
1015 u64 value;
1016
1017 if (!pr)
1018 return -EINVAL;
1019
1020 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1021 return -EINVAL;
1022
1023 if (!pr->flags.throttling)
1024 return -ENODEV;
1025
1026 if (!force && (state == pr->throttling.state))
1027 return 0;
1028
1029 if (state < pr->throttling_platform_limit)
1030 return -EPERM;
1031
1032 value = 0;
1033 ret = acpi_get_throttling_value(pr, state, &value);
1034 if (ret >= 0) {
1035 acpi_write_throttling_state(pr, value);
1036 pr->throttling.state = state;
1037 }
1038
1039 return 0;
1040}
1041
1042static long acpi_processor_throttling_fn(void *data)
1043{
1044 struct acpi_processor_throttling_arg *arg = data;
1045 struct acpi_processor *pr = arg->pr;
1046
1047 return pr->throttling.acpi_processor_set_throttling(pr,
1048 arg->target_state, arg->force);
1049}
1050
1051static int __acpi_processor_set_throttling(struct acpi_processor *pr,
1052 int state, bool force, bool direct)
1053{
1054 int ret = 0;
1055 unsigned int i;
1056 struct acpi_processor *match_pr;
1057 struct acpi_processor_throttling *p_throttling;
1058 struct acpi_processor_throttling_arg arg;
1059 struct throttling_tstate t_state;
1060
1061 if (!pr)
1062 return -EINVAL;
1063
1064 if (!pr->flags.throttling)
1065 return -ENODEV;
1066
1067 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1068 return -EINVAL;
1069
1070 if (cpu_is_offline(pr->id)) {
1071 /*
1072 * the cpu pointed by pr->id is offline. Unnecessary to change
1073 * the throttling state any more.
1074 */
1075 return -ENODEV;
1076 }
1077
1078 t_state.target_state = state;
1079 p_throttling = &(pr->throttling);
1080
1081 /*
1082 * The throttling notifier will be called for every
1083 * affected cpu in order to get one proper T-state.
1084 * The notifier event is THROTTLING_PRECHANGE.
1085 */
1086 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1087 t_state.cpu = i;
1088 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1089 &t_state);
1090 }
1091 /*
1092 * The function of acpi_processor_set_throttling will be called
1093 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1094 * it is necessary to call it for every affected cpu. Otherwise
1095 * it can be called only for the cpu pointed by pr.
1096 */
1097 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1098 arg.pr = pr;
1099 arg.target_state = state;
1100 arg.force = force;
1101 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg,
1102 direct);
1103 } else {
1104 /*
1105 * When the T-state coordination is SW_ALL or HW_ALL,
1106 * it is necessary to set T-state for every affected
1107 * cpus.
1108 */
1109 for_each_cpu_and(i, cpu_online_mask,
1110 p_throttling->shared_cpu_map) {
1111 match_pr = per_cpu(processors, i);
1112 /*
1113 * If the pointer is invalid, we will report the
1114 * error message and continue.
1115 */
1116 if (!match_pr) {
1117 acpi_handle_debug(pr->handle,
1118 "Invalid Pointer for CPU %d\n", i);
1119 continue;
1120 }
1121 /*
1122 * If the throttling control is unsupported on CPU i,
1123 * we will report the error message and continue.
1124 */
1125 if (!match_pr->flags.throttling) {
1126 acpi_handle_debug(pr->handle,
1127 "Throttling Control unsupported on CPU %d\n", i);
1128 continue;
1129 }
1130
1131 arg.pr = match_pr;
1132 arg.target_state = state;
1133 arg.force = force;
1134 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn,
1135 &arg, direct);
1136 }
1137 }
1138 /*
1139 * After the set_throttling is called, the
1140 * throttling notifier is called for every
1141 * affected cpu to update the T-states.
1142 * The notifier event is THROTTLING_POSTCHANGE
1143 */
1144 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1145 t_state.cpu = i;
1146 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1147 &t_state);
1148 }
1149
1150 return ret;
1151}
1152
1153int acpi_processor_set_throttling(struct acpi_processor *pr, int state,
1154 bool force)
1155{
1156 return __acpi_processor_set_throttling(pr, state, force, false);
1157}
1158
1159int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1160{
1161 int result = 0;
1162 struct acpi_processor_throttling *pthrottling;
1163
1164 acpi_handle_debug(pr->handle,
1165 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1166 pr->throttling.address,
1167 pr->throttling.duty_offset,
1168 pr->throttling.duty_width);
1169
1170 /*
1171 * Evaluate _PTC, _TSS and _TPC
1172 * They must all be present or none of them can be used.
1173 */
1174 if (acpi_processor_get_throttling_control(pr) ||
1175 acpi_processor_get_throttling_states(pr) ||
1176 acpi_processor_get_platform_limit(pr)) {
1177 pr->throttling.acpi_processor_get_throttling =
1178 &acpi_processor_get_throttling_fadt;
1179 pr->throttling.acpi_processor_set_throttling =
1180 &acpi_processor_set_throttling_fadt;
1181 if (acpi_processor_get_fadt_info(pr))
1182 return 0;
1183 } else {
1184 pr->throttling.acpi_processor_get_throttling =
1185 &acpi_processor_get_throttling_ptc;
1186 pr->throttling.acpi_processor_set_throttling =
1187 &acpi_processor_set_throttling_ptc;
1188 }
1189
1190 /*
1191 * If TSD package for one CPU can't be parsed successfully, it means
1192 * that this CPU will have no coordination with other CPUs.
1193 */
1194 if (acpi_processor_get_tsd(pr)) {
1195 pthrottling = &pr->throttling;
1196 pthrottling->tsd_valid_flag = 0;
1197 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1198 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1199 }
1200
1201 /*
1202 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1203 * This shouldn't be an issue as few (if any) mobile systems ever
1204 * used this part.
1205 */
1206 if (errata.piix4.throttle) {
1207 acpi_handle_debug(pr->handle,
1208 "Throttling not supported on PIIX4 A- or B-step\n");
1209 return 0;
1210 }
1211
1212 acpi_handle_debug(pr->handle, "Found %d throttling states\n",
1213 pr->throttling.state_count);
1214
1215 pr->flags.throttling = 1;
1216
1217 /*
1218 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1219 * thermal) decide to lower performance if it so chooses, but for now
1220 * we'll crank up the speed.
1221 */
1222
1223 result = acpi_processor_get_throttling(pr);
1224 if (result)
1225 goto end;
1226
1227 if (pr->throttling.state) {
1228 acpi_handle_debug(pr->handle,
1229 "Disabling throttling (was T%d)\n",
1230 pr->throttling.state);
1231 result = acpi_processor_set_throttling(pr, 0, false);
1232 if (result)
1233 goto end;
1234 }
1235
1236end:
1237 if (result)
1238 pr->flags.throttling = 0;
1239
1240 return result;
1241}
1242
1/*
2 * processor_throttling.c - Throttling submodule of the ACPI processor driver
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * - Added processor hotplug support
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or (at
15 * your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * General Public License for more details.
21 *
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23 */
24
25#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/slab.h>
28#include <linux/init.h>
29#include <linux/sched.h>
30#include <linux/cpufreq.h>
31#include <linux/acpi.h>
32#include <acpi/processor.h>
33#include <asm/io.h>
34#include <linux/uaccess.h>
35
36#define PREFIX "ACPI: "
37
38#define ACPI_PROCESSOR_CLASS "processor"
39#define _COMPONENT ACPI_PROCESSOR_COMPONENT
40ACPI_MODULE_NAME("processor_throttling");
41
42/* ignore_tpc:
43 * 0 -> acpi processor driver doesn't ignore _TPC values
44 * 1 -> acpi processor driver ignores _TPC values
45 */
46static int ignore_tpc;
47module_param(ignore_tpc, int, 0644);
48MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
49
50struct throttling_tstate {
51 unsigned int cpu; /* cpu nr */
52 int target_state; /* target T-state */
53};
54
55struct acpi_processor_throttling_arg {
56 struct acpi_processor *pr;
57 int target_state;
58 bool force;
59};
60
61#define THROTTLING_PRECHANGE (1)
62#define THROTTLING_POSTCHANGE (2)
63
64static int acpi_processor_get_throttling(struct acpi_processor *pr);
65static int __acpi_processor_set_throttling(struct acpi_processor *pr,
66 int state, bool force, bool direct);
67
68static int acpi_processor_update_tsd_coord(void)
69{
70 int count, count_target;
71 int retval = 0;
72 unsigned int i, j;
73 cpumask_var_t covered_cpus;
74 struct acpi_processor *pr, *match_pr;
75 struct acpi_tsd_package *pdomain, *match_pdomain;
76 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
77
78 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
79 return -ENOMEM;
80
81 /*
82 * Now that we have _TSD data from all CPUs, lets setup T-state
83 * coordination between all CPUs.
84 */
85 for_each_possible_cpu(i) {
86 pr = per_cpu(processors, i);
87 if (!pr)
88 continue;
89
90 /* Basic validity check for domain info */
91 pthrottling = &(pr->throttling);
92
93 /*
94 * If tsd package for one cpu is invalid, the coordination
95 * among all CPUs is thought as invalid.
96 * Maybe it is ugly.
97 */
98 if (!pthrottling->tsd_valid_flag) {
99 retval = -EINVAL;
100 break;
101 }
102 }
103 if (retval)
104 goto err_ret;
105
106 for_each_possible_cpu(i) {
107 pr = per_cpu(processors, i);
108 if (!pr)
109 continue;
110
111 if (cpumask_test_cpu(i, covered_cpus))
112 continue;
113 pthrottling = &pr->throttling;
114
115 pdomain = &(pthrottling->domain_info);
116 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
117 cpumask_set_cpu(i, covered_cpus);
118 /*
119 * If the number of processor in the TSD domain is 1, it is
120 * unnecessary to parse the coordination for this CPU.
121 */
122 if (pdomain->num_processors <= 1)
123 continue;
124
125 /* Validate the Domain info */
126 count_target = pdomain->num_processors;
127 count = 1;
128
129 for_each_possible_cpu(j) {
130 if (i == j)
131 continue;
132
133 match_pr = per_cpu(processors, j);
134 if (!match_pr)
135 continue;
136
137 match_pthrottling = &(match_pr->throttling);
138 match_pdomain = &(match_pthrottling->domain_info);
139 if (match_pdomain->domain != pdomain->domain)
140 continue;
141
142 /* Here i and j are in the same domain.
143 * If two TSD packages have the same domain, they
144 * should have the same num_porcessors and
145 * coordination type. Otherwise it will be regarded
146 * as illegal.
147 */
148 if (match_pdomain->num_processors != count_target) {
149 retval = -EINVAL;
150 goto err_ret;
151 }
152
153 if (pdomain->coord_type != match_pdomain->coord_type) {
154 retval = -EINVAL;
155 goto err_ret;
156 }
157
158 cpumask_set_cpu(j, covered_cpus);
159 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
160 count++;
161 }
162 for_each_possible_cpu(j) {
163 if (i == j)
164 continue;
165
166 match_pr = per_cpu(processors, j);
167 if (!match_pr)
168 continue;
169
170 match_pthrottling = &(match_pr->throttling);
171 match_pdomain = &(match_pthrottling->domain_info);
172 if (match_pdomain->domain != pdomain->domain)
173 continue;
174
175 /*
176 * If some CPUS have the same domain, they
177 * will have the same shared_cpu_map.
178 */
179 cpumask_copy(match_pthrottling->shared_cpu_map,
180 pthrottling->shared_cpu_map);
181 }
182 }
183
184err_ret:
185 free_cpumask_var(covered_cpus);
186
187 for_each_possible_cpu(i) {
188 pr = per_cpu(processors, i);
189 if (!pr)
190 continue;
191
192 /*
193 * Assume no coordination on any error parsing domain info.
194 * The coordination type will be forced as SW_ALL.
195 */
196 if (retval) {
197 pthrottling = &(pr->throttling);
198 cpumask_clear(pthrottling->shared_cpu_map);
199 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
200 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
201 }
202 }
203
204 return retval;
205}
206
207/*
208 * Update the T-state coordination after the _TSD
209 * data for all cpus is obtained.
210 */
211void acpi_processor_throttling_init(void)
212{
213 if (acpi_processor_update_tsd_coord()) {
214 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
215 "Assume no T-state coordination\n"));
216 }
217
218 return;
219}
220
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 bool is_dead)
379{
380 int result = 0;
381
382 if (is_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 /*
680 * We don't care about error returns - we just try to mark
681 * these reserved so that nobody else is confused into thinking
682 * that this region might be unused..
683 *
684 * (In particular, allocating the IO range for Cardbus)
685 */
686 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
687
688 pr->throttling.state = 0;
689
690 duty_mask = pr->throttling.state_count - 1;
691
692 duty_mask <<= pr->throttling.duty_offset;
693
694 local_irq_disable();
695
696 value = inl(pr->throttling.address);
697
698 /*
699 * Compute the current throttling state when throttling is enabled
700 * (bit 4 is on).
701 */
702 if (value & 0x10) {
703 duty_value = value & duty_mask;
704 duty_value >>= pr->throttling.duty_offset;
705
706 if (duty_value)
707 state = pr->throttling.state_count - duty_value;
708 }
709
710 pr->throttling.state = state;
711
712 local_irq_enable();
713
714 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
715 "Throttling state is T%d (%d%% throttling applied)\n",
716 state, pr->throttling.states[state].performance));
717
718 return 0;
719}
720
721#ifdef CONFIG_X86
722static int acpi_throttling_rdmsr(u64 *value)
723{
724 u64 msr_high, msr_low;
725 u64 msr = 0;
726 int ret = -1;
727
728 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
729 !this_cpu_has(X86_FEATURE_ACPI)) {
730 printk(KERN_ERR PREFIX
731 "HARDWARE addr space,NOT supported yet\n");
732 } else {
733 msr_low = 0;
734 msr_high = 0;
735 rdmsr_safe(MSR_IA32_THERM_CONTROL,
736 (u32 *)&msr_low , (u32 *) &msr_high);
737 msr = (msr_high << 32) | msr_low;
738 *value = (u64) msr;
739 ret = 0;
740 }
741 return ret;
742}
743
744static int acpi_throttling_wrmsr(u64 value)
745{
746 int ret = -1;
747 u64 msr;
748
749 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
750 !this_cpu_has(X86_FEATURE_ACPI)) {
751 printk(KERN_ERR PREFIX
752 "HARDWARE addr space,NOT supported yet\n");
753 } else {
754 msr = value;
755 wrmsr_safe(MSR_IA32_THERM_CONTROL,
756 msr & 0xffffffff, msr >> 32);
757 ret = 0;
758 }
759 return ret;
760}
761#else
762static int acpi_throttling_rdmsr(u64 *value)
763{
764 printk(KERN_ERR PREFIX
765 "HARDWARE addr space,NOT supported yet\n");
766 return -1;
767}
768
769static int acpi_throttling_wrmsr(u64 value)
770{
771 printk(KERN_ERR PREFIX
772 "HARDWARE addr space,NOT supported yet\n");
773 return -1;
774}
775#endif
776
777static int acpi_read_throttling_status(struct acpi_processor *pr,
778 u64 *value)
779{
780 u32 bit_width, bit_offset;
781 u32 ptc_value;
782 u64 ptc_mask;
783 struct acpi_processor_throttling *throttling;
784 int ret = -1;
785
786 throttling = &pr->throttling;
787 switch (throttling->status_register.space_id) {
788 case ACPI_ADR_SPACE_SYSTEM_IO:
789 bit_width = throttling->status_register.bit_width;
790 bit_offset = throttling->status_register.bit_offset;
791
792 acpi_os_read_port((acpi_io_address) throttling->status_register.
793 address, &ptc_value,
794 (u32) (bit_width + bit_offset));
795 ptc_mask = (1 << bit_width) - 1;
796 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
797 ret = 0;
798 break;
799 case ACPI_ADR_SPACE_FIXED_HARDWARE:
800 ret = acpi_throttling_rdmsr(value);
801 break;
802 default:
803 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
804 (u32) (throttling->status_register.space_id));
805 }
806 return ret;
807}
808
809static int acpi_write_throttling_state(struct acpi_processor *pr,
810 u64 value)
811{
812 u32 bit_width, bit_offset;
813 u64 ptc_value;
814 u64 ptc_mask;
815 struct acpi_processor_throttling *throttling;
816 int ret = -1;
817
818 throttling = &pr->throttling;
819 switch (throttling->control_register.space_id) {
820 case ACPI_ADR_SPACE_SYSTEM_IO:
821 bit_width = throttling->control_register.bit_width;
822 bit_offset = throttling->control_register.bit_offset;
823 ptc_mask = (1 << bit_width) - 1;
824 ptc_value = value & ptc_mask;
825
826 acpi_os_write_port((acpi_io_address) throttling->
827 control_register.address,
828 (u32) (ptc_value << bit_offset),
829 (u32) (bit_width + bit_offset));
830 ret = 0;
831 break;
832 case ACPI_ADR_SPACE_FIXED_HARDWARE:
833 ret = acpi_throttling_wrmsr(value);
834 break;
835 default:
836 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
837 (u32) (throttling->control_register.space_id));
838 }
839 return ret;
840}
841
842static int acpi_get_throttling_state(struct acpi_processor *pr,
843 u64 value)
844{
845 int i;
846
847 for (i = 0; i < pr->throttling.state_count; i++) {
848 struct acpi_processor_tx_tss *tx =
849 (struct acpi_processor_tx_tss *)&(pr->throttling.
850 states_tss[i]);
851 if (tx->control == value)
852 return i;
853 }
854 return -1;
855}
856
857static int acpi_get_throttling_value(struct acpi_processor *pr,
858 int state, u64 *value)
859{
860 int ret = -1;
861
862 if (state >= 0 && state <= pr->throttling.state_count) {
863 struct acpi_processor_tx_tss *tx =
864 (struct acpi_processor_tx_tss *)&(pr->throttling.
865 states_tss[state]);
866 *value = tx->control;
867 ret = 0;
868 }
869 return ret;
870}
871
872static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
873{
874 int state = 0;
875 int ret;
876 u64 value;
877
878 if (!pr)
879 return -EINVAL;
880
881 if (!pr->flags.throttling)
882 return -ENODEV;
883
884 pr->throttling.state = 0;
885
886 value = 0;
887 ret = acpi_read_throttling_status(pr, &value);
888 if (ret >= 0) {
889 state = acpi_get_throttling_state(pr, value);
890 if (state == -1) {
891 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
892 "Invalid throttling state, reset\n"));
893 state = 0;
894 ret = __acpi_processor_set_throttling(pr, state, true,
895 true);
896 if (ret)
897 return ret;
898 }
899 pr->throttling.state = state;
900 }
901
902 return 0;
903}
904
905static long __acpi_processor_get_throttling(void *data)
906{
907 struct acpi_processor *pr = data;
908
909 return pr->throttling.acpi_processor_get_throttling(pr);
910}
911
912static int call_on_cpu(int cpu, long (*fn)(void *), void *arg, bool direct)
913{
914 if (direct || (is_percpu_thread() && cpu == smp_processor_id()))
915 return fn(arg);
916 return work_on_cpu(cpu, fn, arg);
917}
918
919static int acpi_processor_get_throttling(struct acpi_processor *pr)
920{
921 if (!pr)
922 return -EINVAL;
923
924 if (!pr->flags.throttling)
925 return -ENODEV;
926
927 /*
928 * This is either called from the CPU hotplug callback of
929 * processor_driver or via the ACPI probe function. In the latter
930 * case the CPU is not guaranteed to be online. Both call sites are
931 * protected against CPU hotplug.
932 */
933 if (!cpu_online(pr->id))
934 return -ENODEV;
935
936 return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false);
937}
938
939static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
940{
941 int i, step;
942
943 if (!pr->throttling.address) {
944 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
945 return -EINVAL;
946 } else if (!pr->throttling.duty_width) {
947 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
948 return -EINVAL;
949 }
950 /* TBD: Support duty_cycle values that span bit 4. */
951 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
952 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
953 return -EINVAL;
954 }
955
956 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
957
958 /*
959 * Compute state values. Note that throttling displays a linear power
960 * performance relationship (at 50% performance the CPU will consume
961 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
962 */
963
964 step = (1000 / pr->throttling.state_count);
965
966 for (i = 0; i < pr->throttling.state_count; i++) {
967 pr->throttling.states[i].performance = 1000 - step * i;
968 pr->throttling.states[i].power = 1000 - step * i;
969 }
970 return 0;
971}
972
973static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
974 int state, bool force)
975{
976 u32 value = 0;
977 u32 duty_mask = 0;
978 u32 duty_value = 0;
979
980 if (!pr)
981 return -EINVAL;
982
983 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
984 return -EINVAL;
985
986 if (!pr->flags.throttling)
987 return -ENODEV;
988
989 if (!force && (state == pr->throttling.state))
990 return 0;
991
992 if (state < pr->throttling_platform_limit)
993 return -EPERM;
994 /*
995 * Calculate the duty_value and duty_mask.
996 */
997 if (state) {
998 duty_value = pr->throttling.state_count - state;
999
1000 duty_value <<= pr->throttling.duty_offset;
1001
1002 /* Used to clear all duty_value bits */
1003 duty_mask = pr->throttling.state_count - 1;
1004
1005 duty_mask <<= acpi_gbl_FADT.duty_offset;
1006 duty_mask = ~duty_mask;
1007 }
1008
1009 local_irq_disable();
1010
1011 /*
1012 * Disable throttling by writing a 0 to bit 4. Note that we must
1013 * turn it off before you can change the duty_value.
1014 */
1015 value = inl(pr->throttling.address);
1016 if (value & 0x10) {
1017 value &= 0xFFFFFFEF;
1018 outl(value, pr->throttling.address);
1019 }
1020
1021 /*
1022 * Write the new duty_value and then enable throttling. Note
1023 * that a state value of 0 leaves throttling disabled.
1024 */
1025 if (state) {
1026 value &= duty_mask;
1027 value |= duty_value;
1028 outl(value, pr->throttling.address);
1029
1030 value |= 0x00000010;
1031 outl(value, pr->throttling.address);
1032 }
1033
1034 pr->throttling.state = state;
1035
1036 local_irq_enable();
1037
1038 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1039 "Throttling state set to T%d (%d%%)\n", state,
1040 (pr->throttling.states[state].performance ? pr->
1041 throttling.states[state].performance / 10 : 0)));
1042
1043 return 0;
1044}
1045
1046static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1047 int state, bool force)
1048{
1049 int ret;
1050 u64 value;
1051
1052 if (!pr)
1053 return -EINVAL;
1054
1055 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1056 return -EINVAL;
1057
1058 if (!pr->flags.throttling)
1059 return -ENODEV;
1060
1061 if (!force && (state == pr->throttling.state))
1062 return 0;
1063
1064 if (state < pr->throttling_platform_limit)
1065 return -EPERM;
1066
1067 value = 0;
1068 ret = acpi_get_throttling_value(pr, state, &value);
1069 if (ret >= 0) {
1070 acpi_write_throttling_state(pr, value);
1071 pr->throttling.state = state;
1072 }
1073
1074 return 0;
1075}
1076
1077static long acpi_processor_throttling_fn(void *data)
1078{
1079 struct acpi_processor_throttling_arg *arg = data;
1080 struct acpi_processor *pr = arg->pr;
1081
1082 return pr->throttling.acpi_processor_set_throttling(pr,
1083 arg->target_state, arg->force);
1084}
1085
1086static int __acpi_processor_set_throttling(struct acpi_processor *pr,
1087 int state, bool force, bool direct)
1088{
1089 int ret = 0;
1090 unsigned int i;
1091 struct acpi_processor *match_pr;
1092 struct acpi_processor_throttling *p_throttling;
1093 struct acpi_processor_throttling_arg arg;
1094 struct throttling_tstate t_state;
1095
1096 if (!pr)
1097 return -EINVAL;
1098
1099 if (!pr->flags.throttling)
1100 return -ENODEV;
1101
1102 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1103 return -EINVAL;
1104
1105 if (cpu_is_offline(pr->id)) {
1106 /*
1107 * the cpu pointed by pr->id is offline. Unnecessary to change
1108 * the throttling state any more.
1109 */
1110 return -ENODEV;
1111 }
1112
1113 t_state.target_state = state;
1114 p_throttling = &(pr->throttling);
1115
1116 /*
1117 * The throttling notifier will be called for every
1118 * affected cpu in order to get one proper T-state.
1119 * The notifier event is THROTTLING_PRECHANGE.
1120 */
1121 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1122 t_state.cpu = i;
1123 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1124 &t_state);
1125 }
1126 /*
1127 * The function of acpi_processor_set_throttling will be called
1128 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1129 * it is necessary to call it for every affected cpu. Otherwise
1130 * it can be called only for the cpu pointed by pr.
1131 */
1132 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1133 arg.pr = pr;
1134 arg.target_state = state;
1135 arg.force = force;
1136 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg,
1137 direct);
1138 } else {
1139 /*
1140 * When the T-state coordination is SW_ALL or HW_ALL,
1141 * it is necessary to set T-state for every affected
1142 * cpus.
1143 */
1144 for_each_cpu_and(i, cpu_online_mask,
1145 p_throttling->shared_cpu_map) {
1146 match_pr = per_cpu(processors, i);
1147 /*
1148 * If the pointer is invalid, we will report the
1149 * error message and continue.
1150 */
1151 if (!match_pr) {
1152 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1153 "Invalid Pointer for CPU %d\n", i));
1154 continue;
1155 }
1156 /*
1157 * If the throttling control is unsupported on CPU i,
1158 * we will report the error message and continue.
1159 */
1160 if (!match_pr->flags.throttling) {
1161 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1162 "Throttling Control is unsupported "
1163 "on CPU %d\n", i));
1164 continue;
1165 }
1166
1167 arg.pr = match_pr;
1168 arg.target_state = state;
1169 arg.force = force;
1170 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn,
1171 &arg, direct);
1172 }
1173 }
1174 /*
1175 * After the set_throttling is called, the
1176 * throttling notifier is called for every
1177 * affected cpu to update the T-states.
1178 * The notifier event is THROTTLING_POSTCHANGE
1179 */
1180 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1181 t_state.cpu = i;
1182 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1183 &t_state);
1184 }
1185
1186 return ret;
1187}
1188
1189int acpi_processor_set_throttling(struct acpi_processor *pr, int state,
1190 bool force)
1191{
1192 return __acpi_processor_set_throttling(pr, state, force, false);
1193}
1194
1195int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1196{
1197 int result = 0;
1198 struct acpi_processor_throttling *pthrottling;
1199
1200 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1201 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1202 pr->throttling.address,
1203 pr->throttling.duty_offset,
1204 pr->throttling.duty_width));
1205
1206 /*
1207 * Evaluate _PTC, _TSS and _TPC
1208 * They must all be present or none of them can be used.
1209 */
1210 if (acpi_processor_get_throttling_control(pr) ||
1211 acpi_processor_get_throttling_states(pr) ||
1212 acpi_processor_get_platform_limit(pr))
1213 {
1214 pr->throttling.acpi_processor_get_throttling =
1215 &acpi_processor_get_throttling_fadt;
1216 pr->throttling.acpi_processor_set_throttling =
1217 &acpi_processor_set_throttling_fadt;
1218 if (acpi_processor_get_fadt_info(pr))
1219 return 0;
1220 } else {
1221 pr->throttling.acpi_processor_get_throttling =
1222 &acpi_processor_get_throttling_ptc;
1223 pr->throttling.acpi_processor_set_throttling =
1224 &acpi_processor_set_throttling_ptc;
1225 }
1226
1227 /*
1228 * If TSD package for one CPU can't be parsed successfully, it means
1229 * that this CPU will have no coordination with other CPUs.
1230 */
1231 if (acpi_processor_get_tsd(pr)) {
1232 pthrottling = &pr->throttling;
1233 pthrottling->tsd_valid_flag = 0;
1234 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1235 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1236 }
1237
1238 /*
1239 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1240 * This shouldn't be an issue as few (if any) mobile systems ever
1241 * used this part.
1242 */
1243 if (errata.piix4.throttle) {
1244 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1245 "Throttling not supported on PIIX4 A- or B-step\n"));
1246 return 0;
1247 }
1248
1249 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1250 pr->throttling.state_count));
1251
1252 pr->flags.throttling = 1;
1253
1254 /*
1255 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1256 * thermal) decide to lower performance if it so chooses, but for now
1257 * we'll crank up the speed.
1258 */
1259
1260 result = acpi_processor_get_throttling(pr);
1261 if (result)
1262 goto end;
1263
1264 if (pr->throttling.state) {
1265 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1266 "Disabling throttling (was T%d)\n",
1267 pr->throttling.state));
1268 result = acpi_processor_set_throttling(pr, 0, false);
1269 if (result)
1270 goto end;
1271 }
1272
1273 end:
1274 if (result)
1275 pr->flags.throttling = 0;
1276
1277 return result;
1278}
1279