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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 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 *
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 */
28
29#include <linux/kernel.h>
30#include <linux/module.h>
31#include <linux/slab.h>
32#include <linux/init.h>
33#include <linux/sched.h>
34#include <linux/cpufreq.h>
35#include <linux/acpi.h>
36#include <acpi/processor.h>
37#include <asm/io.h>
38#include <asm/uaccess.h>
39
40#define PREFIX "ACPI: "
41
42#define ACPI_PROCESSOR_CLASS "processor"
43#define _COMPONENT ACPI_PROCESSOR_COMPONENT
44ACPI_MODULE_NAME("processor_throttling");
45
46/* ignore_tpc:
47 * 0 -> acpi processor driver doesn't ignore _TPC values
48 * 1 -> acpi processor driver ignores _TPC values
49 */
50static int ignore_tpc;
51module_param(ignore_tpc, int, 0644);
52MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
53
54struct throttling_tstate {
55 unsigned int cpu; /* cpu nr */
56 int target_state; /* target T-state */
57};
58
59struct acpi_processor_throttling_arg {
60 struct acpi_processor *pr;
61 int target_state;
62 bool force;
63};
64
65#define THROTTLING_PRECHANGE (1)
66#define THROTTLING_POSTCHANGE (2)
67
68static int acpi_processor_get_throttling(struct acpi_processor *pr);
69int acpi_processor_set_throttling(struct acpi_processor *pr,
70 int state, bool force);
71
72static int acpi_processor_update_tsd_coord(void)
73{
74 int count, count_target;
75 int retval = 0;
76 unsigned int i, j;
77 cpumask_var_t covered_cpus;
78 struct acpi_processor *pr, *match_pr;
79 struct acpi_tsd_package *pdomain, *match_pdomain;
80 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
81
82 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
83 return -ENOMEM;
84
85 /*
86 * Now that we have _TSD data from all CPUs, lets setup T-state
87 * coordination between all CPUs.
88 */
89 for_each_possible_cpu(i) {
90 pr = per_cpu(processors, i);
91 if (!pr)
92 continue;
93
94 /* Basic validity check for domain info */
95 pthrottling = &(pr->throttling);
96
97 /*
98 * If tsd package for one cpu is invalid, the coordination
99 * among all CPUs is thought as invalid.
100 * Maybe it is ugly.
101 */
102 if (!pthrottling->tsd_valid_flag) {
103 retval = -EINVAL;
104 break;
105 }
106 }
107 if (retval)
108 goto err_ret;
109
110 for_each_possible_cpu(i) {
111 pr = per_cpu(processors, i);
112 if (!pr)
113 continue;
114
115 if (cpumask_test_cpu(i, covered_cpus))
116 continue;
117 pthrottling = &pr->throttling;
118
119 pdomain = &(pthrottling->domain_info);
120 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
121 cpumask_set_cpu(i, covered_cpus);
122 /*
123 * If the number of processor in the TSD domain is 1, it is
124 * unnecessary to parse the coordination for this CPU.
125 */
126 if (pdomain->num_processors <= 1)
127 continue;
128
129 /* Validate the Domain info */
130 count_target = pdomain->num_processors;
131 count = 1;
132
133 for_each_possible_cpu(j) {
134 if (i == j)
135 continue;
136
137 match_pr = per_cpu(processors, j);
138 if (!match_pr)
139 continue;
140
141 match_pthrottling = &(match_pr->throttling);
142 match_pdomain = &(match_pthrottling->domain_info);
143 if (match_pdomain->domain != pdomain->domain)
144 continue;
145
146 /* Here i and j are in the same domain.
147 * If two TSD packages have the same domain, they
148 * should have the same num_porcessors and
149 * coordination type. Otherwise it will be regarded
150 * as illegal.
151 */
152 if (match_pdomain->num_processors != count_target) {
153 retval = -EINVAL;
154 goto err_ret;
155 }
156
157 if (pdomain->coord_type != match_pdomain->coord_type) {
158 retval = -EINVAL;
159 goto err_ret;
160 }
161
162 cpumask_set_cpu(j, covered_cpus);
163 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
164 count++;
165 }
166 for_each_possible_cpu(j) {
167 if (i == j)
168 continue;
169
170 match_pr = per_cpu(processors, j);
171 if (!match_pr)
172 continue;
173
174 match_pthrottling = &(match_pr->throttling);
175 match_pdomain = &(match_pthrottling->domain_info);
176 if (match_pdomain->domain != pdomain->domain)
177 continue;
178
179 /*
180 * If some CPUS have the same domain, they
181 * will have the same shared_cpu_map.
182 */
183 cpumask_copy(match_pthrottling->shared_cpu_map,
184 pthrottling->shared_cpu_map);
185 }
186 }
187
188err_ret:
189 free_cpumask_var(covered_cpus);
190
191 for_each_possible_cpu(i) {
192 pr = per_cpu(processors, i);
193 if (!pr)
194 continue;
195
196 /*
197 * Assume no coordination on any error parsing domain info.
198 * The coordination type will be forced as SW_ALL.
199 */
200 if (retval) {
201 pthrottling = &(pr->throttling);
202 cpumask_clear(pthrottling->shared_cpu_map);
203 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
204 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
205 }
206 }
207
208 return retval;
209}
210
211/*
212 * Update the T-state coordination after the _TSD
213 * data for all cpus is obtained.
214 */
215void acpi_processor_throttling_init(void)
216{
217 if (acpi_processor_update_tsd_coord()) {
218 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
219 "Assume no T-state coordination\n"));
220 }
221
222 return;
223}
224
225static int acpi_processor_throttling_notifier(unsigned long event, void *data)
226{
227 struct throttling_tstate *p_tstate = data;
228 struct acpi_processor *pr;
229 unsigned int cpu ;
230 int target_state;
231 struct acpi_processor_limit *p_limit;
232 struct acpi_processor_throttling *p_throttling;
233
234 cpu = p_tstate->cpu;
235 pr = per_cpu(processors, cpu);
236 if (!pr) {
237 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
238 return 0;
239 }
240 if (!pr->flags.throttling) {
241 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
242 "unsupported on CPU %d\n", cpu));
243 return 0;
244 }
245 target_state = p_tstate->target_state;
246 p_throttling = &(pr->throttling);
247 switch (event) {
248 case THROTTLING_PRECHANGE:
249 /*
250 * Prechange event is used to choose one proper t-state,
251 * which meets the limits of thermal, user and _TPC.
252 */
253 p_limit = &pr->limit;
254 if (p_limit->thermal.tx > target_state)
255 target_state = p_limit->thermal.tx;
256 if (p_limit->user.tx > target_state)
257 target_state = p_limit->user.tx;
258 if (pr->throttling_platform_limit > target_state)
259 target_state = pr->throttling_platform_limit;
260 if (target_state >= p_throttling->state_count) {
261 printk(KERN_WARNING
262 "Exceed the limit of T-state \n");
263 target_state = p_throttling->state_count - 1;
264 }
265 p_tstate->target_state = target_state;
266 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
267 "target T-state of CPU %d is T%d\n",
268 cpu, target_state));
269 break;
270 case THROTTLING_POSTCHANGE:
271 /*
272 * Postchange event is only used to update the
273 * T-state flag of acpi_processor_throttling.
274 */
275 p_throttling->state = target_state;
276 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
277 "CPU %d is switched to T%d\n",
278 cpu, target_state));
279 break;
280 default:
281 printk(KERN_WARNING
282 "Unsupported Throttling notifier event\n");
283 break;
284 }
285
286 return 0;
287}
288
289/*
290 * _TPC - Throttling Present Capabilities
291 */
292static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
293{
294 acpi_status status = 0;
295 unsigned long long tpc = 0;
296
297 if (!pr)
298 return -EINVAL;
299
300 if (ignore_tpc)
301 goto end;
302
303 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
304 if (ACPI_FAILURE(status)) {
305 if (status != AE_NOT_FOUND) {
306 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
307 }
308 return -ENODEV;
309 }
310
311end:
312 pr->throttling_platform_limit = (int)tpc;
313 return 0;
314}
315
316int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
317{
318 int result = 0;
319 int throttling_limit;
320 int current_state;
321 struct acpi_processor_limit *limit;
322 int target_state;
323
324 if (ignore_tpc)
325 return 0;
326
327 result = acpi_processor_get_platform_limit(pr);
328 if (result) {
329 /* Throttling Limit is unsupported */
330 return result;
331 }
332
333 throttling_limit = pr->throttling_platform_limit;
334 if (throttling_limit >= pr->throttling.state_count) {
335 /* Uncorrect Throttling Limit */
336 return -EINVAL;
337 }
338
339 current_state = pr->throttling.state;
340 if (current_state > throttling_limit) {
341 /*
342 * The current state can meet the requirement of
343 * _TPC limit. But it is reasonable that OSPM changes
344 * t-states from high to low for better performance.
345 * Of course the limit condition of thermal
346 * and user should be considered.
347 */
348 limit = &pr->limit;
349 target_state = throttling_limit;
350 if (limit->thermal.tx > target_state)
351 target_state = limit->thermal.tx;
352 if (limit->user.tx > target_state)
353 target_state = limit->user.tx;
354 } else if (current_state == throttling_limit) {
355 /*
356 * Unnecessary to change the throttling state
357 */
358 return 0;
359 } else {
360 /*
361 * If the current state is lower than the limit of _TPC, it
362 * will be forced to switch to the throttling state defined
363 * by throttling_platfor_limit.
364 * Because the previous state meets with the limit condition
365 * of thermal and user, it is unnecessary to check it again.
366 */
367 target_state = throttling_limit;
368 }
369 return acpi_processor_set_throttling(pr, target_state, false);
370}
371
372/*
373 * This function is used to reevaluate whether the T-state is valid
374 * after one CPU is onlined/offlined.
375 * It is noted that it won't reevaluate the following properties for
376 * the T-state.
377 * 1. Control method.
378 * 2. the number of supported T-state
379 * 3. TSD domain
380 */
381void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
382 unsigned long action)
383{
384 int result = 0;
385
386 if (action == CPU_DEAD) {
387 /* When one CPU is offline, the T-state throttling
388 * will be invalidated.
389 */
390 pr->flags.throttling = 0;
391 return;
392 }
393 /* the following is to recheck whether the T-state is valid for
394 * the online CPU
395 */
396 if (!pr->throttling.state_count) {
397 /* If the number of T-state is invalid, it is
398 * invalidated.
399 */
400 pr->flags.throttling = 0;
401 return;
402 }
403 pr->flags.throttling = 1;
404
405 /* Disable throttling (if enabled). We'll let subsequent
406 * policy (e.g.thermal) decide to lower performance if it
407 * so chooses, but for now we'll crank up the speed.
408 */
409
410 result = acpi_processor_get_throttling(pr);
411 if (result)
412 goto end;
413
414 if (pr->throttling.state) {
415 result = acpi_processor_set_throttling(pr, 0, false);
416 if (result)
417 goto end;
418 }
419
420end:
421 if (result)
422 pr->flags.throttling = 0;
423}
424/*
425 * _PTC - Processor Throttling Control (and status) register location
426 */
427static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
428{
429 int result = 0;
430 acpi_status status = 0;
431 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
432 union acpi_object *ptc = NULL;
433 union acpi_object obj = { 0 };
434 struct acpi_processor_throttling *throttling;
435
436 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
437 if (ACPI_FAILURE(status)) {
438 if (status != AE_NOT_FOUND) {
439 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
440 }
441 return -ENODEV;
442 }
443
444 ptc = (union acpi_object *)buffer.pointer;
445 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
446 || (ptc->package.count != 2)) {
447 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
448 result = -EFAULT;
449 goto end;
450 }
451
452 /*
453 * control_register
454 */
455
456 obj = ptc->package.elements[0];
457
458 if ((obj.type != ACPI_TYPE_BUFFER)
459 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
460 || (obj.buffer.pointer == NULL)) {
461 printk(KERN_ERR PREFIX
462 "Invalid _PTC data (control_register)\n");
463 result = -EFAULT;
464 goto end;
465 }
466 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
467 sizeof(struct acpi_ptc_register));
468
469 /*
470 * status_register
471 */
472
473 obj = ptc->package.elements[1];
474
475 if ((obj.type != ACPI_TYPE_BUFFER)
476 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
477 || (obj.buffer.pointer == NULL)) {
478 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
479 result = -EFAULT;
480 goto end;
481 }
482
483 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
484 sizeof(struct acpi_ptc_register));
485
486 throttling = &pr->throttling;
487
488 if ((throttling->control_register.bit_width +
489 throttling->control_register.bit_offset) > 32) {
490 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
491 result = -EFAULT;
492 goto end;
493 }
494
495 if ((throttling->status_register.bit_width +
496 throttling->status_register.bit_offset) > 32) {
497 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
498 result = -EFAULT;
499 goto end;
500 }
501
502 end:
503 kfree(buffer.pointer);
504
505 return result;
506}
507
508/*
509 * _TSS - Throttling Supported States
510 */
511static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
512{
513 int result = 0;
514 acpi_status status = AE_OK;
515 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
516 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
517 struct acpi_buffer state = { 0, NULL };
518 union acpi_object *tss = NULL;
519 int i;
520
521 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
522 if (ACPI_FAILURE(status)) {
523 if (status != AE_NOT_FOUND) {
524 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
525 }
526 return -ENODEV;
527 }
528
529 tss = buffer.pointer;
530 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
531 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
532 result = -EFAULT;
533 goto end;
534 }
535
536 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
537 tss->package.count));
538
539 pr->throttling.state_count = tss->package.count;
540 pr->throttling.states_tss =
541 kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
542 GFP_KERNEL);
543 if (!pr->throttling.states_tss) {
544 result = -ENOMEM;
545 goto end;
546 }
547
548 for (i = 0; i < pr->throttling.state_count; i++) {
549
550 struct acpi_processor_tx_tss *tx =
551 (struct acpi_processor_tx_tss *)&(pr->throttling.
552 states_tss[i]);
553
554 state.length = sizeof(struct acpi_processor_tx_tss);
555 state.pointer = tx;
556
557 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
558
559 status = acpi_extract_package(&(tss->package.elements[i]),
560 &format, &state);
561 if (ACPI_FAILURE(status)) {
562 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
563 result = -EFAULT;
564 kfree(pr->throttling.states_tss);
565 goto end;
566 }
567
568 if (!tx->freqpercentage) {
569 printk(KERN_ERR PREFIX
570 "Invalid _TSS data: freq is zero\n");
571 result = -EFAULT;
572 kfree(pr->throttling.states_tss);
573 goto end;
574 }
575 }
576
577 end:
578 kfree(buffer.pointer);
579
580 return result;
581}
582
583/*
584 * _TSD - T-State Dependencies
585 */
586static int acpi_processor_get_tsd(struct acpi_processor *pr)
587{
588 int result = 0;
589 acpi_status status = AE_OK;
590 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
591 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
592 struct acpi_buffer state = { 0, NULL };
593 union acpi_object *tsd = NULL;
594 struct acpi_tsd_package *pdomain;
595 struct acpi_processor_throttling *pthrottling;
596
597 pthrottling = &pr->throttling;
598 pthrottling->tsd_valid_flag = 0;
599
600 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
601 if (ACPI_FAILURE(status)) {
602 if (status != AE_NOT_FOUND) {
603 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
604 }
605 return -ENODEV;
606 }
607
608 tsd = buffer.pointer;
609 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
610 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
611 result = -EFAULT;
612 goto end;
613 }
614
615 if (tsd->package.count != 1) {
616 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
617 result = -EFAULT;
618 goto end;
619 }
620
621 pdomain = &(pr->throttling.domain_info);
622
623 state.length = sizeof(struct acpi_tsd_package);
624 state.pointer = pdomain;
625
626 status = acpi_extract_package(&(tsd->package.elements[0]),
627 &format, &state);
628 if (ACPI_FAILURE(status)) {
629 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
630 result = -EFAULT;
631 goto end;
632 }
633
634 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
635 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
636 result = -EFAULT;
637 goto end;
638 }
639
640 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
641 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
642 result = -EFAULT;
643 goto end;
644 }
645
646 pthrottling = &pr->throttling;
647 pthrottling->tsd_valid_flag = 1;
648 pthrottling->shared_type = pdomain->coord_type;
649 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
650 /*
651 * If the coordination type is not defined in ACPI spec,
652 * the tsd_valid_flag will be clear and coordination type
653 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
654 */
655 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
656 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
657 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
658 pthrottling->tsd_valid_flag = 0;
659 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
660 }
661
662 end:
663 kfree(buffer.pointer);
664 return result;
665}
666
667/* --------------------------------------------------------------------------
668 Throttling Control
669 -------------------------------------------------------------------------- */
670static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
671{
672 int state = 0;
673 u32 value = 0;
674 u32 duty_mask = 0;
675 u32 duty_value = 0;
676
677 if (!pr)
678 return -EINVAL;
679
680 if (!pr->flags.throttling)
681 return -ENODEV;
682
683 pr->throttling.state = 0;
684
685 duty_mask = pr->throttling.state_count - 1;
686
687 duty_mask <<= pr->throttling.duty_offset;
688
689 local_irq_disable();
690
691 value = inl(pr->throttling.address);
692
693 /*
694 * Compute the current throttling state when throttling is enabled
695 * (bit 4 is on).
696 */
697 if (value & 0x10) {
698 duty_value = value & duty_mask;
699 duty_value >>= pr->throttling.duty_offset;
700
701 if (duty_value)
702 state = pr->throttling.state_count - duty_value;
703 }
704
705 pr->throttling.state = state;
706
707 local_irq_enable();
708
709 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
710 "Throttling state is T%d (%d%% throttling applied)\n",
711 state, pr->throttling.states[state].performance));
712
713 return 0;
714}
715
716#ifdef CONFIG_X86
717static int acpi_throttling_rdmsr(u64 *value)
718{
719 u64 msr_high, msr_low;
720 u64 msr = 0;
721 int ret = -1;
722
723 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
724 !this_cpu_has(X86_FEATURE_ACPI)) {
725 printk(KERN_ERR PREFIX
726 "HARDWARE addr space,NOT supported yet\n");
727 } else {
728 msr_low = 0;
729 msr_high = 0;
730 rdmsr_safe(MSR_IA32_THERM_CONTROL,
731 (u32 *)&msr_low , (u32 *) &msr_high);
732 msr = (msr_high << 32) | msr_low;
733 *value = (u64) msr;
734 ret = 0;
735 }
736 return ret;
737}
738
739static int acpi_throttling_wrmsr(u64 value)
740{
741 int ret = -1;
742 u64 msr;
743
744 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
745 !this_cpu_has(X86_FEATURE_ACPI)) {
746 printk(KERN_ERR PREFIX
747 "HARDWARE addr space,NOT supported yet\n");
748 } else {
749 msr = value;
750 wrmsr_safe(MSR_IA32_THERM_CONTROL,
751 msr & 0xffffffff, msr >> 32);
752 ret = 0;
753 }
754 return ret;
755}
756#else
757static int acpi_throttling_rdmsr(u64 *value)
758{
759 printk(KERN_ERR PREFIX
760 "HARDWARE addr space,NOT supported yet\n");
761 return -1;
762}
763
764static int acpi_throttling_wrmsr(u64 value)
765{
766 printk(KERN_ERR PREFIX
767 "HARDWARE addr space,NOT supported yet\n");
768 return -1;
769}
770#endif
771
772static int acpi_read_throttling_status(struct acpi_processor *pr,
773 u64 *value)
774{
775 u32 bit_width, bit_offset;
776 u32 ptc_value;
777 u64 ptc_mask;
778 struct acpi_processor_throttling *throttling;
779 int ret = -1;
780
781 throttling = &pr->throttling;
782 switch (throttling->status_register.space_id) {
783 case ACPI_ADR_SPACE_SYSTEM_IO:
784 bit_width = throttling->status_register.bit_width;
785 bit_offset = throttling->status_register.bit_offset;
786
787 acpi_os_read_port((acpi_io_address) throttling->status_register.
788 address, &ptc_value,
789 (u32) (bit_width + bit_offset));
790 ptc_mask = (1 << bit_width) - 1;
791 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
792 ret = 0;
793 break;
794 case ACPI_ADR_SPACE_FIXED_HARDWARE:
795 ret = acpi_throttling_rdmsr(value);
796 break;
797 default:
798 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
799 (u32) (throttling->status_register.space_id));
800 }
801 return ret;
802}
803
804static int acpi_write_throttling_state(struct acpi_processor *pr,
805 u64 value)
806{
807 u32 bit_width, bit_offset;
808 u64 ptc_value;
809 u64 ptc_mask;
810 struct acpi_processor_throttling *throttling;
811 int ret = -1;
812
813 throttling = &pr->throttling;
814 switch (throttling->control_register.space_id) {
815 case ACPI_ADR_SPACE_SYSTEM_IO:
816 bit_width = throttling->control_register.bit_width;
817 bit_offset = throttling->control_register.bit_offset;
818 ptc_mask = (1 << bit_width) - 1;
819 ptc_value = value & ptc_mask;
820
821 acpi_os_write_port((acpi_io_address) throttling->
822 control_register.address,
823 (u32) (ptc_value << bit_offset),
824 (u32) (bit_width + bit_offset));
825 ret = 0;
826 break;
827 case ACPI_ADR_SPACE_FIXED_HARDWARE:
828 ret = acpi_throttling_wrmsr(value);
829 break;
830 default:
831 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
832 (u32) (throttling->control_register.space_id));
833 }
834 return ret;
835}
836
837static int acpi_get_throttling_state(struct acpi_processor *pr,
838 u64 value)
839{
840 int i;
841
842 for (i = 0; i < pr->throttling.state_count; i++) {
843 struct acpi_processor_tx_tss *tx =
844 (struct acpi_processor_tx_tss *)&(pr->throttling.
845 states_tss[i]);
846 if (tx->control == value)
847 return i;
848 }
849 return -1;
850}
851
852static int acpi_get_throttling_value(struct acpi_processor *pr,
853 int state, u64 *value)
854{
855 int ret = -1;
856
857 if (state >= 0 && state <= pr->throttling.state_count) {
858 struct acpi_processor_tx_tss *tx =
859 (struct acpi_processor_tx_tss *)&(pr->throttling.
860 states_tss[state]);
861 *value = tx->control;
862 ret = 0;
863 }
864 return ret;
865}
866
867static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
868{
869 int state = 0;
870 int ret;
871 u64 value;
872
873 if (!pr)
874 return -EINVAL;
875
876 if (!pr->flags.throttling)
877 return -ENODEV;
878
879 pr->throttling.state = 0;
880
881 value = 0;
882 ret = acpi_read_throttling_status(pr, &value);
883 if (ret >= 0) {
884 state = acpi_get_throttling_state(pr, value);
885 if (state == -1) {
886 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
887 "Invalid throttling state, reset\n"));
888 state = 0;
889 ret = acpi_processor_set_throttling(pr, state, true);
890 if (ret)
891 return ret;
892 }
893 pr->throttling.state = state;
894 }
895
896 return 0;
897}
898
899static int acpi_processor_get_throttling(struct acpi_processor *pr)
900{
901 cpumask_var_t saved_mask;
902 int ret;
903
904 if (!pr)
905 return -EINVAL;
906
907 if (!pr->flags.throttling)
908 return -ENODEV;
909
910 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
911 return -ENOMEM;
912
913 /*
914 * Migrate task to the cpu pointed by pr.
915 */
916 cpumask_copy(saved_mask, ¤t->cpus_allowed);
917 /* FIXME: use work_on_cpu() */
918 if (set_cpus_allowed_ptr(current, cpumask_of(pr->id))) {
919 /* Can't migrate to the target pr->id CPU. Exit */
920 free_cpumask_var(saved_mask);
921 return -ENODEV;
922 }
923 ret = pr->throttling.acpi_processor_get_throttling(pr);
924 /* restore the previous state */
925 set_cpus_allowed_ptr(current, saved_mask);
926 free_cpumask_var(saved_mask);
927
928 return ret;
929}
930
931static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
932{
933 int i, step;
934
935 if (!pr->throttling.address) {
936 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
937 return -EINVAL;
938 } else if (!pr->throttling.duty_width) {
939 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
940 return -EINVAL;
941 }
942 /* TBD: Support duty_cycle values that span bit 4. */
943 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
944 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
945 return -EINVAL;
946 }
947
948 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
949
950 /*
951 * Compute state values. Note that throttling displays a linear power
952 * performance relationship (at 50% performance the CPU will consume
953 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
954 */
955
956 step = (1000 / pr->throttling.state_count);
957
958 for (i = 0; i < pr->throttling.state_count; i++) {
959 pr->throttling.states[i].performance = 1000 - step * i;
960 pr->throttling.states[i].power = 1000 - step * i;
961 }
962 return 0;
963}
964
965static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
966 int state, bool force)
967{
968 u32 value = 0;
969 u32 duty_mask = 0;
970 u32 duty_value = 0;
971
972 if (!pr)
973 return -EINVAL;
974
975 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
976 return -EINVAL;
977
978 if (!pr->flags.throttling)
979 return -ENODEV;
980
981 if (!force && (state == pr->throttling.state))
982 return 0;
983
984 if (state < pr->throttling_platform_limit)
985 return -EPERM;
986 /*
987 * Calculate the duty_value and duty_mask.
988 */
989 if (state) {
990 duty_value = pr->throttling.state_count - state;
991
992 duty_value <<= pr->throttling.duty_offset;
993
994 /* Used to clear all duty_value bits */
995 duty_mask = pr->throttling.state_count - 1;
996
997 duty_mask <<= acpi_gbl_FADT.duty_offset;
998 duty_mask = ~duty_mask;
999 }
1000
1001 local_irq_disable();
1002
1003 /*
1004 * Disable throttling by writing a 0 to bit 4. Note that we must
1005 * turn it off before you can change the duty_value.
1006 */
1007 value = inl(pr->throttling.address);
1008 if (value & 0x10) {
1009 value &= 0xFFFFFFEF;
1010 outl(value, pr->throttling.address);
1011 }
1012
1013 /*
1014 * Write the new duty_value and then enable throttling. Note
1015 * that a state value of 0 leaves throttling disabled.
1016 */
1017 if (state) {
1018 value &= duty_mask;
1019 value |= duty_value;
1020 outl(value, pr->throttling.address);
1021
1022 value |= 0x00000010;
1023 outl(value, pr->throttling.address);
1024 }
1025
1026 pr->throttling.state = state;
1027
1028 local_irq_enable();
1029
1030 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1031 "Throttling state set to T%d (%d%%)\n", state,
1032 (pr->throttling.states[state].performance ? pr->
1033 throttling.states[state].performance / 10 : 0)));
1034
1035 return 0;
1036}
1037
1038static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1039 int state, bool force)
1040{
1041 int ret;
1042 u64 value;
1043
1044 if (!pr)
1045 return -EINVAL;
1046
1047 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1048 return -EINVAL;
1049
1050 if (!pr->flags.throttling)
1051 return -ENODEV;
1052
1053 if (!force && (state == pr->throttling.state))
1054 return 0;
1055
1056 if (state < pr->throttling_platform_limit)
1057 return -EPERM;
1058
1059 value = 0;
1060 ret = acpi_get_throttling_value(pr, state, &value);
1061 if (ret >= 0) {
1062 acpi_write_throttling_state(pr, value);
1063 pr->throttling.state = state;
1064 }
1065
1066 return 0;
1067}
1068
1069static long acpi_processor_throttling_fn(void *data)
1070{
1071 struct acpi_processor_throttling_arg *arg = data;
1072 struct acpi_processor *pr = arg->pr;
1073
1074 return pr->throttling.acpi_processor_set_throttling(pr,
1075 arg->target_state, arg->force);
1076}
1077
1078int acpi_processor_set_throttling(struct acpi_processor *pr,
1079 int state, bool force)
1080{
1081 int ret = 0;
1082 unsigned int i;
1083 struct acpi_processor *match_pr;
1084 struct acpi_processor_throttling *p_throttling;
1085 struct acpi_processor_throttling_arg arg;
1086 struct throttling_tstate t_state;
1087
1088 if (!pr)
1089 return -EINVAL;
1090
1091 if (!pr->flags.throttling)
1092 return -ENODEV;
1093
1094 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1095 return -EINVAL;
1096
1097 if (cpu_is_offline(pr->id)) {
1098 /*
1099 * the cpu pointed by pr->id is offline. Unnecessary to change
1100 * the throttling state any more.
1101 */
1102 return -ENODEV;
1103 }
1104
1105 t_state.target_state = state;
1106 p_throttling = &(pr->throttling);
1107
1108 /*
1109 * The throttling notifier will be called for every
1110 * affected cpu in order to get one proper T-state.
1111 * The notifier event is THROTTLING_PRECHANGE.
1112 */
1113 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1114 t_state.cpu = i;
1115 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1116 &t_state);
1117 }
1118 /*
1119 * The function of acpi_processor_set_throttling will be called
1120 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1121 * it is necessary to call it for every affected cpu. Otherwise
1122 * it can be called only for the cpu pointed by pr.
1123 */
1124 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1125 arg.pr = pr;
1126 arg.target_state = state;
1127 arg.force = force;
1128 ret = work_on_cpu(pr->id, acpi_processor_throttling_fn, &arg);
1129 } else {
1130 /*
1131 * When the T-state coordination is SW_ALL or HW_ALL,
1132 * it is necessary to set T-state for every affected
1133 * cpus.
1134 */
1135 for_each_cpu_and(i, cpu_online_mask,
1136 p_throttling->shared_cpu_map) {
1137 match_pr = per_cpu(processors, i);
1138 /*
1139 * If the pointer is invalid, we will report the
1140 * error message and continue.
1141 */
1142 if (!match_pr) {
1143 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1144 "Invalid Pointer for CPU %d\n", i));
1145 continue;
1146 }
1147 /*
1148 * If the throttling control is unsupported on CPU i,
1149 * we will report the error message and continue.
1150 */
1151 if (!match_pr->flags.throttling) {
1152 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1153 "Throttling Control is unsupported "
1154 "on CPU %d\n", i));
1155 continue;
1156 }
1157
1158 arg.pr = match_pr;
1159 arg.target_state = state;
1160 arg.force = force;
1161 ret = work_on_cpu(pr->id, acpi_processor_throttling_fn,
1162 &arg);
1163 }
1164 }
1165 /*
1166 * After the set_throttling is called, the
1167 * throttling notifier is called for every
1168 * affected cpu to update the T-states.
1169 * The notifier event is THROTTLING_POSTCHANGE
1170 */
1171 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1172 t_state.cpu = i;
1173 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1174 &t_state);
1175 }
1176
1177 return ret;
1178}
1179
1180int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1181{
1182 int result = 0;
1183 struct acpi_processor_throttling *pthrottling;
1184
1185 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1186 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1187 pr->throttling.address,
1188 pr->throttling.duty_offset,
1189 pr->throttling.duty_width));
1190
1191 /*
1192 * Evaluate _PTC, _TSS and _TPC
1193 * They must all be present or none of them can be used.
1194 */
1195 if (acpi_processor_get_throttling_control(pr) ||
1196 acpi_processor_get_throttling_states(pr) ||
1197 acpi_processor_get_platform_limit(pr))
1198 {
1199 pr->throttling.acpi_processor_get_throttling =
1200 &acpi_processor_get_throttling_fadt;
1201 pr->throttling.acpi_processor_set_throttling =
1202 &acpi_processor_set_throttling_fadt;
1203 if (acpi_processor_get_fadt_info(pr))
1204 return 0;
1205 } else {
1206 pr->throttling.acpi_processor_get_throttling =
1207 &acpi_processor_get_throttling_ptc;
1208 pr->throttling.acpi_processor_set_throttling =
1209 &acpi_processor_set_throttling_ptc;
1210 }
1211
1212 /*
1213 * If TSD package for one CPU can't be parsed successfully, it means
1214 * that this CPU will have no coordination with other CPUs.
1215 */
1216 if (acpi_processor_get_tsd(pr)) {
1217 pthrottling = &pr->throttling;
1218 pthrottling->tsd_valid_flag = 0;
1219 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1220 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1221 }
1222
1223 /*
1224 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1225 * This shouldn't be an issue as few (if any) mobile systems ever
1226 * used this part.
1227 */
1228 if (errata.piix4.throttle) {
1229 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1230 "Throttling not supported on PIIX4 A- or B-step\n"));
1231 return 0;
1232 }
1233
1234 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1235 pr->throttling.state_count));
1236
1237 pr->flags.throttling = 1;
1238
1239 /*
1240 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1241 * thermal) decide to lower performance if it so chooses, but for now
1242 * we'll crank up the speed.
1243 */
1244
1245 result = acpi_processor_get_throttling(pr);
1246 if (result)
1247 goto end;
1248
1249 if (pr->throttling.state) {
1250 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1251 "Disabling throttling (was T%d)\n",
1252 pr->throttling.state));
1253 result = acpi_processor_set_throttling(pr, 0, false);
1254 if (result)
1255 goto end;
1256 }
1257
1258 end:
1259 if (result)
1260 pr->flags.throttling = 0;
1261
1262 return result;
1263}
1264