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