1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * processor_throttling.c - Throttling submodule of the ACPI processor driver
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
8 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9 * - Added processor hotplug support
10 */
11
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/init.h>
16 #include <linux/sched.h>
17 #include <linux/cpufreq.h>
18 #include <linux/acpi.h>
19 #include <acpi/processor.h>
20 #include <asm/io.h>
21 #include <linux/uaccess.h>
22
23 #define PREFIX "ACPI: "
24
25 #define ACPI_PROCESSOR_CLASS "processor"
26 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
27 ACPI_MODULE_NAME("processor_throttling");
28
29 /* ignore_tpc:
30 * 0 -> acpi processor driver doesn't ignore _TPC values
31 * 1 -> acpi processor driver ignores _TPC values
32 */
33 static int ignore_tpc;
34 module_param(ignore_tpc, int, 0644);
35 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
36
37 struct throttling_tstate {
38 unsigned int cpu; /* cpu nr */
39 int target_state; /* target T-state */
40 };
41
42 struct acpi_processor_throttling_arg {
43 struct acpi_processor *pr;
44 int target_state;
45 bool force;
46 };
47
48 #define THROTTLING_PRECHANGE (1)
49 #define THROTTLING_POSTCHANGE (2)
50
51 static int acpi_processor_get_throttling(struct acpi_processor *pr);
52 static int __acpi_processor_set_throttling(struct acpi_processor *pr,
53 int state, bool force, bool direct);
54
acpi_processor_update_tsd_coord(void)55 static int acpi_processor_update_tsd_coord(void)
56 {
57 int count, count_target;
58 int retval = 0;
59 unsigned int i, j;
60 cpumask_var_t covered_cpus;
61 struct acpi_processor *pr, *match_pr;
62 struct acpi_tsd_package *pdomain, *match_pdomain;
63 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
64
65 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
66 return -ENOMEM;
67
68 /*
69 * Now that we have _TSD data from all CPUs, lets setup T-state
70 * coordination between all CPUs.
71 */
72 for_each_possible_cpu(i) {
73 pr = per_cpu(processors, i);
74 if (!pr)
75 continue;
76
77 /* Basic validity check for domain info */
78 pthrottling = &(pr->throttling);
79
80 /*
81 * If tsd package for one cpu is invalid, the coordination
82 * among all CPUs is thought as invalid.
83 * Maybe it is ugly.
84 */
85 if (!pthrottling->tsd_valid_flag) {
86 retval = -EINVAL;
87 break;
88 }
89 }
90 if (retval)
91 goto err_ret;
92
93 for_each_possible_cpu(i) {
94 pr = per_cpu(processors, i);
95 if (!pr)
96 continue;
97
98 if (cpumask_test_cpu(i, covered_cpus))
99 continue;
100 pthrottling = &pr->throttling;
101
102 pdomain = &(pthrottling->domain_info);
103 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
104 cpumask_set_cpu(i, covered_cpus);
105 /*
106 * If the number of processor in the TSD domain is 1, it is
107 * unnecessary to parse the coordination for this CPU.
108 */
109 if (pdomain->num_processors <= 1)
110 continue;
111
112 /* Validate the Domain info */
113 count_target = pdomain->num_processors;
114 count = 1;
115
116 for_each_possible_cpu(j) {
117 if (i == j)
118 continue;
119
120 match_pr = per_cpu(processors, j);
121 if (!match_pr)
122 continue;
123
124 match_pthrottling = &(match_pr->throttling);
125 match_pdomain = &(match_pthrottling->domain_info);
126 if (match_pdomain->domain != pdomain->domain)
127 continue;
128
129 /* Here i and j are in the same domain.
130 * If two TSD packages have the same domain, they
131 * should have the same num_porcessors and
132 * coordination type. Otherwise it will be regarded
133 * as illegal.
134 */
135 if (match_pdomain->num_processors != count_target) {
136 retval = -EINVAL;
137 goto err_ret;
138 }
139
140 if (pdomain->coord_type != match_pdomain->coord_type) {
141 retval = -EINVAL;
142 goto err_ret;
143 }
144
145 cpumask_set_cpu(j, covered_cpus);
146 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
147 count++;
148 }
149 for_each_possible_cpu(j) {
150 if (i == j)
151 continue;
152
153 match_pr = per_cpu(processors, j);
154 if (!match_pr)
155 continue;
156
157 match_pthrottling = &(match_pr->throttling);
158 match_pdomain = &(match_pthrottling->domain_info);
159 if (match_pdomain->domain != pdomain->domain)
160 continue;
161
162 /*
163 * If some CPUS have the same domain, they
164 * will have the same shared_cpu_map.
165 */
166 cpumask_copy(match_pthrottling->shared_cpu_map,
167 pthrottling->shared_cpu_map);
168 }
169 }
170
171 err_ret:
172 free_cpumask_var(covered_cpus);
173
174 for_each_possible_cpu(i) {
175 pr = per_cpu(processors, i);
176 if (!pr)
177 continue;
178
179 /*
180 * Assume no coordination on any error parsing domain info.
181 * The coordination type will be forced as SW_ALL.
182 */
183 if (retval) {
184 pthrottling = &(pr->throttling);
185 cpumask_clear(pthrottling->shared_cpu_map);
186 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
187 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
188 }
189 }
190
191 return retval;
192 }
193
194 /*
195 * Update the T-state coordination after the _TSD
196 * data for all cpus is obtained.
197 */
acpi_processor_throttling_init(void)198 void acpi_processor_throttling_init(void)
199 {
200 if (acpi_processor_update_tsd_coord()) {
201 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
202 "Assume no T-state coordination\n"));
203 }
204
205 return;
206 }
207
acpi_processor_throttling_notifier(unsigned long event,void * data)208 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
209 {
210 struct throttling_tstate *p_tstate = data;
211 struct acpi_processor *pr;
212 unsigned int cpu ;
213 int target_state;
214 struct acpi_processor_limit *p_limit;
215 struct acpi_processor_throttling *p_throttling;
216
217 cpu = p_tstate->cpu;
218 pr = per_cpu(processors, cpu);
219 if (!pr) {
220 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
221 return 0;
222 }
223 if (!pr->flags.throttling) {
224 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
225 "unsupported on CPU %d\n", cpu));
226 return 0;
227 }
228 target_state = p_tstate->target_state;
229 p_throttling = &(pr->throttling);
230 switch (event) {
231 case THROTTLING_PRECHANGE:
232 /*
233 * Prechange event is used to choose one proper t-state,
234 * which meets the limits of thermal, user and _TPC.
235 */
236 p_limit = &pr->limit;
237 if (p_limit->thermal.tx > target_state)
238 target_state = p_limit->thermal.tx;
239 if (p_limit->user.tx > target_state)
240 target_state = p_limit->user.tx;
241 if (pr->throttling_platform_limit > target_state)
242 target_state = pr->throttling_platform_limit;
243 if (target_state >= p_throttling->state_count) {
244 printk(KERN_WARNING
245 "Exceed the limit of T-state \n");
246 target_state = p_throttling->state_count - 1;
247 }
248 p_tstate->target_state = target_state;
249 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
250 "target T-state of CPU %d is T%d\n",
251 cpu, target_state));
252 break;
253 case THROTTLING_POSTCHANGE:
254 /*
255 * Postchange event is only used to update the
256 * T-state flag of acpi_processor_throttling.
257 */
258 p_throttling->state = target_state;
259 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
260 "CPU %d is switched to T%d\n",
261 cpu, target_state));
262 break;
263 default:
264 printk(KERN_WARNING
265 "Unsupported Throttling notifier event\n");
266 break;
267 }
268
269 return 0;
270 }
271
272 /*
273 * _TPC - Throttling Present Capabilities
274 */
acpi_processor_get_platform_limit(struct acpi_processor * pr)275 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
276 {
277 acpi_status status = 0;
278 unsigned long long tpc = 0;
279
280 if (!pr)
281 return -EINVAL;
282
283 if (ignore_tpc)
284 goto end;
285
286 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
287 if (ACPI_FAILURE(status)) {
288 if (status != AE_NOT_FOUND) {
289 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
290 }
291 return -ENODEV;
292 }
293
294 end:
295 pr->throttling_platform_limit = (int)tpc;
296 return 0;
297 }
298
acpi_processor_tstate_has_changed(struct acpi_processor * pr)299 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
300 {
301 int result = 0;
302 int throttling_limit;
303 int current_state;
304 struct acpi_processor_limit *limit;
305 int target_state;
306
307 if (ignore_tpc)
308 return 0;
309
310 result = acpi_processor_get_platform_limit(pr);
311 if (result) {
312 /* Throttling Limit is unsupported */
313 return result;
314 }
315
316 throttling_limit = pr->throttling_platform_limit;
317 if (throttling_limit >= pr->throttling.state_count) {
318 /* Uncorrect Throttling Limit */
319 return -EINVAL;
320 }
321
322 current_state = pr->throttling.state;
323 if (current_state > throttling_limit) {
324 /*
325 * The current state can meet the requirement of
326 * _TPC limit. But it is reasonable that OSPM changes
327 * t-states from high to low for better performance.
328 * Of course the limit condition of thermal
329 * and user should be considered.
330 */
331 limit = &pr->limit;
332 target_state = throttling_limit;
333 if (limit->thermal.tx > target_state)
334 target_state = limit->thermal.tx;
335 if (limit->user.tx > target_state)
336 target_state = limit->user.tx;
337 } else if (current_state == throttling_limit) {
338 /*
339 * Unnecessary to change the throttling state
340 */
341 return 0;
342 } else {
343 /*
344 * If the current state is lower than the limit of _TPC, it
345 * will be forced to switch to the throttling state defined
346 * by throttling_platfor_limit.
347 * Because the previous state meets with the limit condition
348 * of thermal and user, it is unnecessary to check it again.
349 */
350 target_state = throttling_limit;
351 }
352 return acpi_processor_set_throttling(pr, target_state, false);
353 }
354
355 /*
356 * This function is used to reevaluate whether the T-state is valid
357 * after one CPU is onlined/offlined.
358 * It is noted that it won't reevaluate the following properties for
359 * the T-state.
360 * 1. Control method.
361 * 2. the number of supported T-state
362 * 3. TSD domain
363 */
acpi_processor_reevaluate_tstate(struct acpi_processor * pr,bool is_dead)364 void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
365 bool is_dead)
366 {
367 int result = 0;
368
369 if (is_dead) {
370 /* When one CPU is offline, the T-state throttling
371 * will be invalidated.
372 */
373 pr->flags.throttling = 0;
374 return;
375 }
376 /* the following is to recheck whether the T-state is valid for
377 * the online CPU
378 */
379 if (!pr->throttling.state_count) {
380 /* If the number of T-state is invalid, it is
381 * invalidated.
382 */
383 pr->flags.throttling = 0;
384 return;
385 }
386 pr->flags.throttling = 1;
387
388 /* Disable throttling (if enabled). We'll let subsequent
389 * policy (e.g.thermal) decide to lower performance if it
390 * so chooses, but for now we'll crank up the speed.
391 */
392
393 result = acpi_processor_get_throttling(pr);
394 if (result)
395 goto end;
396
397 if (pr->throttling.state) {
398 result = acpi_processor_set_throttling(pr, 0, false);
399 if (result)
400 goto end;
401 }
402
403 end:
404 if (result)
405 pr->flags.throttling = 0;
406 }
407 /*
408 * _PTC - Processor Throttling Control (and status) register location
409 */
acpi_processor_get_throttling_control(struct acpi_processor * pr)410 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
411 {
412 int result = 0;
413 acpi_status status = 0;
414 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
415 union acpi_object *ptc = NULL;
416 union acpi_object obj = { 0 };
417 struct acpi_processor_throttling *throttling;
418
419 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
420 if (ACPI_FAILURE(status)) {
421 if (status != AE_NOT_FOUND) {
422 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
423 }
424 return -ENODEV;
425 }
426
427 ptc = (union acpi_object *)buffer.pointer;
428 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
429 || (ptc->package.count != 2)) {
430 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
431 result = -EFAULT;
432 goto end;
433 }
434
435 /*
436 * control_register
437 */
438
439 obj = ptc->package.elements[0];
440
441 if ((obj.type != ACPI_TYPE_BUFFER)
442 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
443 || (obj.buffer.pointer == NULL)) {
444 printk(KERN_ERR PREFIX
445 "Invalid _PTC data (control_register)\n");
446 result = -EFAULT;
447 goto end;
448 }
449 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
450 sizeof(struct acpi_ptc_register));
451
452 /*
453 * status_register
454 */
455
456 obj = ptc->package.elements[1];
457
458 if ((obj.type != ACPI_TYPE_BUFFER)
459 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
460 || (obj.buffer.pointer == NULL)) {
461 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
462 result = -EFAULT;
463 goto end;
464 }
465
466 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
467 sizeof(struct acpi_ptc_register));
468
469 throttling = &pr->throttling;
470
471 if ((throttling->control_register.bit_width +
472 throttling->control_register.bit_offset) > 32) {
473 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
474 result = -EFAULT;
475 goto end;
476 }
477
478 if ((throttling->status_register.bit_width +
479 throttling->status_register.bit_offset) > 32) {
480 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
481 result = -EFAULT;
482 goto end;
483 }
484
485 end:
486 kfree(buffer.pointer);
487
488 return result;
489 }
490
491 /*
492 * _TSS - Throttling Supported States
493 */
acpi_processor_get_throttling_states(struct acpi_processor * pr)494 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
495 {
496 int result = 0;
497 acpi_status status = AE_OK;
498 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
499 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
500 struct acpi_buffer state = { 0, NULL };
501 union acpi_object *tss = NULL;
502 int i;
503
504 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
505 if (ACPI_FAILURE(status)) {
506 if (status != AE_NOT_FOUND) {
507 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
508 }
509 return -ENODEV;
510 }
511
512 tss = buffer.pointer;
513 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
514 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
515 result = -EFAULT;
516 goto end;
517 }
518
519 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
520 tss->package.count));
521
522 pr->throttling.state_count = tss->package.count;
523 pr->throttling.states_tss =
524 kmalloc_array(tss->package.count,
525 sizeof(struct acpi_processor_tx_tss),
526 GFP_KERNEL);
527 if (!pr->throttling.states_tss) {
528 result = -ENOMEM;
529 goto end;
530 }
531
532 for (i = 0; i < pr->throttling.state_count; i++) {
533
534 struct acpi_processor_tx_tss *tx =
535 (struct acpi_processor_tx_tss *)&(pr->throttling.
536 states_tss[i]);
537
538 state.length = sizeof(struct acpi_processor_tx_tss);
539 state.pointer = tx;
540
541 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
542
543 status = acpi_extract_package(&(tss->package.elements[i]),
544 &format, &state);
545 if (ACPI_FAILURE(status)) {
546 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
547 result = -EFAULT;
548 kfree(pr->throttling.states_tss);
549 goto end;
550 }
551
552 if (!tx->freqpercentage) {
553 printk(KERN_ERR PREFIX
554 "Invalid _TSS data: freq is zero\n");
555 result = -EFAULT;
556 kfree(pr->throttling.states_tss);
557 goto end;
558 }
559 }
560
561 end:
562 kfree(buffer.pointer);
563
564 return result;
565 }
566
567 /*
568 * _TSD - T-State Dependencies
569 */
acpi_processor_get_tsd(struct acpi_processor * pr)570 static int acpi_processor_get_tsd(struct acpi_processor *pr)
571 {
572 int result = 0;
573 acpi_status status = AE_OK;
574 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
575 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
576 struct acpi_buffer state = { 0, NULL };
577 union acpi_object *tsd = NULL;
578 struct acpi_tsd_package *pdomain;
579 struct acpi_processor_throttling *pthrottling;
580
581 pthrottling = &pr->throttling;
582 pthrottling->tsd_valid_flag = 0;
583
584 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
585 if (ACPI_FAILURE(status)) {
586 if (status != AE_NOT_FOUND) {
587 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
588 }
589 return -ENODEV;
590 }
591
592 tsd = buffer.pointer;
593 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
594 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
595 result = -EFAULT;
596 goto end;
597 }
598
599 if (tsd->package.count != 1) {
600 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
601 result = -EFAULT;
602 goto end;
603 }
604
605 pdomain = &(pr->throttling.domain_info);
606
607 state.length = sizeof(struct acpi_tsd_package);
608 state.pointer = pdomain;
609
610 status = acpi_extract_package(&(tsd->package.elements[0]),
611 &format, &state);
612 if (ACPI_FAILURE(status)) {
613 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
614 result = -EFAULT;
615 goto end;
616 }
617
618 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
619 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
620 result = -EFAULT;
621 goto end;
622 }
623
624 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
625 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
626 result = -EFAULT;
627 goto end;
628 }
629
630 pthrottling = &pr->throttling;
631 pthrottling->tsd_valid_flag = 1;
632 pthrottling->shared_type = pdomain->coord_type;
633 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
634 /*
635 * If the coordination type is not defined in ACPI spec,
636 * the tsd_valid_flag will be clear and coordination type
637 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
638 */
639 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
640 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
641 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
642 pthrottling->tsd_valid_flag = 0;
643 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
644 }
645
646 end:
647 kfree(buffer.pointer);
648 return result;
649 }
650
651 /* --------------------------------------------------------------------------
652 Throttling Control
653 -------------------------------------------------------------------------- */
acpi_processor_get_throttling_fadt(struct acpi_processor * pr)654 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
655 {
656 int state = 0;
657 u32 value = 0;
658 u32 duty_mask = 0;
659 u32 duty_value = 0;
660
661 if (!pr)
662 return -EINVAL;
663
664 if (!pr->flags.throttling)
665 return -ENODEV;
666
667 /*
668 * We don't care about error returns - we just try to mark
669 * these reserved so that nobody else is confused into thinking
670 * that this region might be unused..
671 *
672 * (In particular, allocating the IO range for Cardbus)
673 */
674 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
675
676 pr->throttling.state = 0;
677
678 duty_mask = pr->throttling.state_count - 1;
679
680 duty_mask <<= pr->throttling.duty_offset;
681
682 local_irq_disable();
683
684 value = inl(pr->throttling.address);
685
686 /*
687 * Compute the current throttling state when throttling is enabled
688 * (bit 4 is on).
689 */
690 if (value & 0x10) {
691 duty_value = value & duty_mask;
692 duty_value >>= pr->throttling.duty_offset;
693
694 if (duty_value)
695 state = pr->throttling.state_count - duty_value;
696 }
697
698 pr->throttling.state = state;
699
700 local_irq_enable();
701
702 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
703 "Throttling state is T%d (%d%% throttling applied)\n",
704 state, pr->throttling.states[state].performance));
705
706 return 0;
707 }
708
709 #ifdef CONFIG_X86
acpi_throttling_rdmsr(u64 * value)710 static int acpi_throttling_rdmsr(u64 *value)
711 {
712 u64 msr_high, msr_low;
713 u64 msr = 0;
714 int ret = -1;
715
716 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
717 !this_cpu_has(X86_FEATURE_ACPI)) {
718 printk(KERN_ERR PREFIX
719 "HARDWARE addr space,NOT supported yet\n");
720 } else {
721 msr_low = 0;
722 msr_high = 0;
723 rdmsr_safe(MSR_IA32_THERM_CONTROL,
724 (u32 *)&msr_low , (u32 *) &msr_high);
725 msr = (msr_high << 32) | msr_low;
726 *value = (u64) msr;
727 ret = 0;
728 }
729 return ret;
730 }
731
acpi_throttling_wrmsr(u64 value)732 static int acpi_throttling_wrmsr(u64 value)
733 {
734 int ret = -1;
735 u64 msr;
736
737 if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
738 !this_cpu_has(X86_FEATURE_ACPI)) {
739 printk(KERN_ERR PREFIX
740 "HARDWARE addr space,NOT supported yet\n");
741 } else {
742 msr = value;
743 wrmsr_safe(MSR_IA32_THERM_CONTROL,
744 msr & 0xffffffff, msr >> 32);
745 ret = 0;
746 }
747 return ret;
748 }
749 #else
acpi_throttling_rdmsr(u64 * value)750 static int acpi_throttling_rdmsr(u64 *value)
751 {
752 printk(KERN_ERR PREFIX
753 "HARDWARE addr space,NOT supported yet\n");
754 return -1;
755 }
756
acpi_throttling_wrmsr(u64 value)757 static int acpi_throttling_wrmsr(u64 value)
758 {
759 printk(KERN_ERR PREFIX
760 "HARDWARE addr space,NOT supported yet\n");
761 return -1;
762 }
763 #endif
764
acpi_read_throttling_status(struct acpi_processor * pr,u64 * value)765 static int acpi_read_throttling_status(struct acpi_processor *pr,
766 u64 *value)
767 {
768 u32 bit_width, bit_offset;
769 u32 ptc_value;
770 u64 ptc_mask;
771 struct acpi_processor_throttling *throttling;
772 int ret = -1;
773
774 throttling = &pr->throttling;
775 switch (throttling->status_register.space_id) {
776 case ACPI_ADR_SPACE_SYSTEM_IO:
777 bit_width = throttling->status_register.bit_width;
778 bit_offset = throttling->status_register.bit_offset;
779
780 acpi_os_read_port((acpi_io_address) throttling->status_register.
781 address, &ptc_value,
782 (u32) (bit_width + bit_offset));
783 ptc_mask = (1 << bit_width) - 1;
784 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
785 ret = 0;
786 break;
787 case ACPI_ADR_SPACE_FIXED_HARDWARE:
788 ret = acpi_throttling_rdmsr(value);
789 break;
790 default:
791 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
792 (u32) (throttling->status_register.space_id));
793 }
794 return ret;
795 }
796
acpi_write_throttling_state(struct acpi_processor * pr,u64 value)797 static int acpi_write_throttling_state(struct acpi_processor *pr,
798 u64 value)
799 {
800 u32 bit_width, bit_offset;
801 u64 ptc_value;
802 u64 ptc_mask;
803 struct acpi_processor_throttling *throttling;
804 int ret = -1;
805
806 throttling = &pr->throttling;
807 switch (throttling->control_register.space_id) {
808 case ACPI_ADR_SPACE_SYSTEM_IO:
809 bit_width = throttling->control_register.bit_width;
810 bit_offset = throttling->control_register.bit_offset;
811 ptc_mask = (1 << bit_width) - 1;
812 ptc_value = value & ptc_mask;
813
814 acpi_os_write_port((acpi_io_address) throttling->
815 control_register.address,
816 (u32) (ptc_value << bit_offset),
817 (u32) (bit_width + bit_offset));
818 ret = 0;
819 break;
820 case ACPI_ADR_SPACE_FIXED_HARDWARE:
821 ret = acpi_throttling_wrmsr(value);
822 break;
823 default:
824 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
825 (u32) (throttling->control_register.space_id));
826 }
827 return ret;
828 }
829
acpi_get_throttling_state(struct acpi_processor * pr,u64 value)830 static int acpi_get_throttling_state(struct acpi_processor *pr,
831 u64 value)
832 {
833 int i;
834
835 for (i = 0; i < pr->throttling.state_count; i++) {
836 struct acpi_processor_tx_tss *tx =
837 (struct acpi_processor_tx_tss *)&(pr->throttling.
838 states_tss[i]);
839 if (tx->control == value)
840 return i;
841 }
842 return -1;
843 }
844
acpi_get_throttling_value(struct acpi_processor * pr,int state,u64 * value)845 static int acpi_get_throttling_value(struct acpi_processor *pr,
846 int state, u64 *value)
847 {
848 int ret = -1;
849
850 if (state >= 0 && state <= pr->throttling.state_count) {
851 struct acpi_processor_tx_tss *tx =
852 (struct acpi_processor_tx_tss *)&(pr->throttling.
853 states_tss[state]);
854 *value = tx->control;
855 ret = 0;
856 }
857 return ret;
858 }
859
acpi_processor_get_throttling_ptc(struct acpi_processor * pr)860 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
861 {
862 int state = 0;
863 int ret;
864 u64 value;
865
866 if (!pr)
867 return -EINVAL;
868
869 if (!pr->flags.throttling)
870 return -ENODEV;
871
872 pr->throttling.state = 0;
873
874 value = 0;
875 ret = acpi_read_throttling_status(pr, &value);
876 if (ret >= 0) {
877 state = acpi_get_throttling_state(pr, value);
878 if (state == -1) {
879 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
880 "Invalid throttling state, reset\n"));
881 state = 0;
882 ret = __acpi_processor_set_throttling(pr, state, true,
883 true);
884 if (ret)
885 return ret;
886 }
887 pr->throttling.state = state;
888 }
889
890 return 0;
891 }
892
__acpi_processor_get_throttling(void * data)893 static long __acpi_processor_get_throttling(void *data)
894 {
895 struct acpi_processor *pr = data;
896
897 return pr->throttling.acpi_processor_get_throttling(pr);
898 }
899
call_on_cpu(int cpu,long (* fn)(void *),void * arg,bool direct)900 static int call_on_cpu(int cpu, long (*fn)(void *), void *arg, bool direct)
901 {
902 if (direct || (is_percpu_thread() && cpu == smp_processor_id()))
903 return fn(arg);
904 return work_on_cpu(cpu, fn, arg);
905 }
906
acpi_processor_get_throttling(struct acpi_processor * pr)907 static int acpi_processor_get_throttling(struct acpi_processor *pr)
908 {
909 if (!pr)
910 return -EINVAL;
911
912 if (!pr->flags.throttling)
913 return -ENODEV;
914
915 /*
916 * This is either called from the CPU hotplug callback of
917 * processor_driver or via the ACPI probe function. In the latter
918 * case the CPU is not guaranteed to be online. Both call sites are
919 * protected against CPU hotplug.
920 */
921 if (!cpu_online(pr->id))
922 return -ENODEV;
923
924 return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false);
925 }
926
acpi_processor_get_fadt_info(struct acpi_processor * pr)927 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
928 {
929 int i, step;
930
931 if (!pr->throttling.address) {
932 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
933 return -EINVAL;
934 } else if (!pr->throttling.duty_width) {
935 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
936 return -EINVAL;
937 }
938 /* TBD: Support duty_cycle values that span bit 4. */
939 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
940 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
941 return -EINVAL;
942 }
943
944 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
945
946 /*
947 * Compute state values. Note that throttling displays a linear power
948 * performance relationship (at 50% performance the CPU will consume
949 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
950 */
951
952 step = (1000 / pr->throttling.state_count);
953
954 for (i = 0; i < pr->throttling.state_count; i++) {
955 pr->throttling.states[i].performance = 1000 - step * i;
956 pr->throttling.states[i].power = 1000 - step * i;
957 }
958 return 0;
959 }
960
acpi_processor_set_throttling_fadt(struct acpi_processor * pr,int state,bool force)961 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
962 int state, bool force)
963 {
964 u32 value = 0;
965 u32 duty_mask = 0;
966 u32 duty_value = 0;
967
968 if (!pr)
969 return -EINVAL;
970
971 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
972 return -EINVAL;
973
974 if (!pr->flags.throttling)
975 return -ENODEV;
976
977 if (!force && (state == pr->throttling.state))
978 return 0;
979
980 if (state < pr->throttling_platform_limit)
981 return -EPERM;
982 /*
983 * Calculate the duty_value and duty_mask.
984 */
985 if (state) {
986 duty_value = pr->throttling.state_count - state;
987
988 duty_value <<= pr->throttling.duty_offset;
989
990 /* Used to clear all duty_value bits */
991 duty_mask = pr->throttling.state_count - 1;
992
993 duty_mask <<= acpi_gbl_FADT.duty_offset;
994 duty_mask = ~duty_mask;
995 }
996
997 local_irq_disable();
998
999 /*
1000 * Disable throttling by writing a 0 to bit 4. Note that we must
1001 * turn it off before you can change the duty_value.
1002 */
1003 value = inl(pr->throttling.address);
1004 if (value & 0x10) {
1005 value &= 0xFFFFFFEF;
1006 outl(value, pr->throttling.address);
1007 }
1008
1009 /*
1010 * Write the new duty_value and then enable throttling. Note
1011 * that a state value of 0 leaves throttling disabled.
1012 */
1013 if (state) {
1014 value &= duty_mask;
1015 value |= duty_value;
1016 outl(value, pr->throttling.address);
1017
1018 value |= 0x00000010;
1019 outl(value, pr->throttling.address);
1020 }
1021
1022 pr->throttling.state = state;
1023
1024 local_irq_enable();
1025
1026 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1027 "Throttling state set to T%d (%d%%)\n", state,
1028 (pr->throttling.states[state].performance ? pr->
1029 throttling.states[state].performance / 10 : 0)));
1030
1031 return 0;
1032 }
1033
acpi_processor_set_throttling_ptc(struct acpi_processor * pr,int state,bool force)1034 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1035 int state, bool force)
1036 {
1037 int ret;
1038 u64 value;
1039
1040 if (!pr)
1041 return -EINVAL;
1042
1043 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1044 return -EINVAL;
1045
1046 if (!pr->flags.throttling)
1047 return -ENODEV;
1048
1049 if (!force && (state == pr->throttling.state))
1050 return 0;
1051
1052 if (state < pr->throttling_platform_limit)
1053 return -EPERM;
1054
1055 value = 0;
1056 ret = acpi_get_throttling_value(pr, state, &value);
1057 if (ret >= 0) {
1058 acpi_write_throttling_state(pr, value);
1059 pr->throttling.state = state;
1060 }
1061
1062 return 0;
1063 }
1064
acpi_processor_throttling_fn(void * data)1065 static long acpi_processor_throttling_fn(void *data)
1066 {
1067 struct acpi_processor_throttling_arg *arg = data;
1068 struct acpi_processor *pr = arg->pr;
1069
1070 return pr->throttling.acpi_processor_set_throttling(pr,
1071 arg->target_state, arg->force);
1072 }
1073
__acpi_processor_set_throttling(struct acpi_processor * pr,int state,bool force,bool direct)1074 static int __acpi_processor_set_throttling(struct acpi_processor *pr,
1075 int state, bool force, bool direct)
1076 {
1077 int ret = 0;
1078 unsigned int i;
1079 struct acpi_processor *match_pr;
1080 struct acpi_processor_throttling *p_throttling;
1081 struct acpi_processor_throttling_arg arg;
1082 struct throttling_tstate t_state;
1083
1084 if (!pr)
1085 return -EINVAL;
1086
1087 if (!pr->flags.throttling)
1088 return -ENODEV;
1089
1090 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1091 return -EINVAL;
1092
1093 if (cpu_is_offline(pr->id)) {
1094 /*
1095 * the cpu pointed by pr->id is offline. Unnecessary to change
1096 * the throttling state any more.
1097 */
1098 return -ENODEV;
1099 }
1100
1101 t_state.target_state = state;
1102 p_throttling = &(pr->throttling);
1103
1104 /*
1105 * The throttling notifier will be called for every
1106 * affected cpu in order to get one proper T-state.
1107 * The notifier event is THROTTLING_PRECHANGE.
1108 */
1109 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1110 t_state.cpu = i;
1111 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1112 &t_state);
1113 }
1114 /*
1115 * The function of acpi_processor_set_throttling will be called
1116 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1117 * it is necessary to call it for every affected cpu. Otherwise
1118 * it can be called only for the cpu pointed by pr.
1119 */
1120 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1121 arg.pr = pr;
1122 arg.target_state = state;
1123 arg.force = force;
1124 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg,
1125 direct);
1126 } else {
1127 /*
1128 * When the T-state coordination is SW_ALL or HW_ALL,
1129 * it is necessary to set T-state for every affected
1130 * cpus.
1131 */
1132 for_each_cpu_and(i, cpu_online_mask,
1133 p_throttling->shared_cpu_map) {
1134 match_pr = per_cpu(processors, i);
1135 /*
1136 * If the pointer is invalid, we will report the
1137 * error message and continue.
1138 */
1139 if (!match_pr) {
1140 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1141 "Invalid Pointer for CPU %d\n", i));
1142 continue;
1143 }
1144 /*
1145 * If the throttling control is unsupported on CPU i,
1146 * we will report the error message and continue.
1147 */
1148 if (!match_pr->flags.throttling) {
1149 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1150 "Throttling Control is unsupported "
1151 "on CPU %d\n", i));
1152 continue;
1153 }
1154
1155 arg.pr = match_pr;
1156 arg.target_state = state;
1157 arg.force = force;
1158 ret = call_on_cpu(pr->id, acpi_processor_throttling_fn,
1159 &arg, direct);
1160 }
1161 }
1162 /*
1163 * After the set_throttling is called, the
1164 * throttling notifier is called for every
1165 * affected cpu to update the T-states.
1166 * The notifier event is THROTTLING_POSTCHANGE
1167 */
1168 for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1169 t_state.cpu = i;
1170 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1171 &t_state);
1172 }
1173
1174 return ret;
1175 }
1176
acpi_processor_set_throttling(struct acpi_processor * pr,int state,bool force)1177 int acpi_processor_set_throttling(struct acpi_processor *pr, int state,
1178 bool force)
1179 {
1180 return __acpi_processor_set_throttling(pr, state, force, false);
1181 }
1182
acpi_processor_get_throttling_info(struct acpi_processor * pr)1183 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1184 {
1185 int result = 0;
1186 struct acpi_processor_throttling *pthrottling;
1187
1188 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1189 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1190 pr->throttling.address,
1191 pr->throttling.duty_offset,
1192 pr->throttling.duty_width));
1193
1194 /*
1195 * Evaluate _PTC, _TSS and _TPC
1196 * They must all be present or none of them can be used.
1197 */
1198 if (acpi_processor_get_throttling_control(pr) ||
1199 acpi_processor_get_throttling_states(pr) ||
1200 acpi_processor_get_platform_limit(pr))
1201 {
1202 pr->throttling.acpi_processor_get_throttling =
1203 &acpi_processor_get_throttling_fadt;
1204 pr->throttling.acpi_processor_set_throttling =
1205 &acpi_processor_set_throttling_fadt;
1206 if (acpi_processor_get_fadt_info(pr))
1207 return 0;
1208 } else {
1209 pr->throttling.acpi_processor_get_throttling =
1210 &acpi_processor_get_throttling_ptc;
1211 pr->throttling.acpi_processor_set_throttling =
1212 &acpi_processor_set_throttling_ptc;
1213 }
1214
1215 /*
1216 * If TSD package for one CPU can't be parsed successfully, it means
1217 * that this CPU will have no coordination with other CPUs.
1218 */
1219 if (acpi_processor_get_tsd(pr)) {
1220 pthrottling = &pr->throttling;
1221 pthrottling->tsd_valid_flag = 0;
1222 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1223 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1224 }
1225
1226 /*
1227 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1228 * This shouldn't be an issue as few (if any) mobile systems ever
1229 * used this part.
1230 */
1231 if (errata.piix4.throttle) {
1232 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1233 "Throttling not supported on PIIX4 A- or B-step\n"));
1234 return 0;
1235 }
1236
1237 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1238 pr->throttling.state_count));
1239
1240 pr->flags.throttling = 1;
1241
1242 /*
1243 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1244 * thermal) decide to lower performance if it so chooses, but for now
1245 * we'll crank up the speed.
1246 */
1247
1248 result = acpi_processor_get_throttling(pr);
1249 if (result)
1250 goto end;
1251
1252 if (pr->throttling.state) {
1253 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1254 "Disabling throttling (was T%d)\n",
1255 pr->throttling.state));
1256 result = acpi_processor_set_throttling(pr, 0, false);
1257 if (result)
1258 goto end;
1259 }
1260
1261 end:
1262 if (result)
1263 pr->flags.throttling = 0;
1264
1265 return result;
1266 }
1267
1268