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Linux 2.6.34-rc3
[pohmelfs.git] / drivers / acpi / processor_throttling.c
blob29c6f5766dcfa1ecee58af693c1dcebde9135bd3
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/init.h>
32 #include <linux/sched.h>
33 #include <linux/cpufreq.h>
34 #include <linux/proc_fs.h>
35 #include <linux/seq_file.h>
36
37 #include <asm/io.h>
38 #include <asm/uaccess.h>
39
40 #include <acpi/acpi_bus.h>
41 #include <acpi/acpi_drivers.h>
42 #include <acpi/processor.h>
43
44 #define PREFIX "ACPI: "
45
46 #define ACPI_PROCESSOR_CLASS "processor"
47 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
48 ACPI_MODULE_NAME("processor_throttling");
49
50 /* ignore_tpc:
51 * 0 -> acpi processor driver doesn't ignore _TPC values
52 * 1 -> acpi processor driver ignores _TPC values
53 */
54 static int ignore_tpc;
55 module_param(ignore_tpc, int, 0644);
56 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
57
58 struct throttling_tstate {
59 unsigned int cpu; /* cpu nr */
60 int target_state; /* target T-state */
61 };
62
63 #define THROTTLING_PRECHANGE (1)
64 #define THROTTLING_POSTCHANGE (2)
65
66 static int acpi_processor_get_throttling(struct acpi_processor *pr);
67 int acpi_processor_set_throttling(struct acpi_processor *pr,
68 int state, bool force);
69
70 static int acpi_processor_update_tsd_coord(void)
71 {
72 int count, count_target;
73 int retval = 0;
74 unsigned int i, j;
75 cpumask_var_t covered_cpus;
76 struct acpi_processor *pr, *match_pr;
77 struct acpi_tsd_package *pdomain, *match_pdomain;
78 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
79
80 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
81 return -ENOMEM;
82
83 /*
84 * Now that we have _TSD data from all CPUs, lets setup T-state
85 * coordination between all CPUs.
86 */
87 for_each_possible_cpu(i) {
88 pr = per_cpu(processors, i);
89 if (!pr)
90 continue;
91
92 /* Basic validity check for domain info */
93 pthrottling = &(pr->throttling);
94
95 /*
96 * If tsd package for one cpu is invalid, the coordination
97 * among all CPUs is thought as invalid.
98 * Maybe it is ugly.
99 */
100 if (!pthrottling->tsd_valid_flag) {
101 retval = -EINVAL;
102 break;
103 }
104 }
105 if (retval)
106 goto err_ret;
107
108 for_each_possible_cpu(i) {
109 pr = per_cpu(processors, i);
110 if (!pr)
111 continue;
112
113 if (cpumask_test_cpu(i, covered_cpus))
114 continue;
115 pthrottling = &pr->throttling;
116
117 pdomain = &(pthrottling->domain_info);
118 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
119 cpumask_set_cpu(i, covered_cpus);
120 /*
121 * If the number of processor in the TSD domain is 1, it is
122 * unnecessary to parse the coordination for this CPU.
123 */
124 if (pdomain->num_processors <= 1)
125 continue;
126
127 /* Validate the Domain info */
128 count_target = pdomain->num_processors;
129 count = 1;
130
131 for_each_possible_cpu(j) {
132 if (i == j)
133 continue;
134
135 match_pr = per_cpu(processors, j);
136 if (!match_pr)
137 continue;
138
139 match_pthrottling = &(match_pr->throttling);
140 match_pdomain = &(match_pthrottling->domain_info);
141 if (match_pdomain->domain != pdomain->domain)
142 continue;
143
144 /* Here i and j are in the same domain.
145 * If two TSD packages have the same domain, they
146 * should have the same num_porcessors and
147 * coordination type. Otherwise it will be regarded
148 * as illegal.
149 */
150 if (match_pdomain->num_processors != count_target) {
151 retval = -EINVAL;
152 goto err_ret;
153 }
154
155 if (pdomain->coord_type != match_pdomain->coord_type) {
156 retval = -EINVAL;
157 goto err_ret;
158 }
159
160 cpumask_set_cpu(j, covered_cpus);
161 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
162 count++;
163 }
164 for_each_possible_cpu(j) {
165 if (i == j)
166 continue;
167
168 match_pr = per_cpu(processors, j);
169 if (!match_pr)
170 continue;
171
172 match_pthrottling = &(match_pr->throttling);
173 match_pdomain = &(match_pthrottling->domain_info);
174 if (match_pdomain->domain != pdomain->domain)
175 continue;
176
177 /*
178 * If some CPUS have the same domain, they
179 * will have the same shared_cpu_map.
180 */
181 cpumask_copy(match_pthrottling->shared_cpu_map,
182 pthrottling->shared_cpu_map);
183 }
184 }
185
186 err_ret:
187 free_cpumask_var(covered_cpus);
188
189 for_each_possible_cpu(i) {
190 pr = per_cpu(processors, i);
191 if (!pr)
192 continue;
193
194 /*
195 * Assume no coordination on any error parsing domain info.
196 * The coordination type will be forced as SW_ALL.
197 */
198 if (retval) {
199 pthrottling = &(pr->throttling);
200 cpumask_clear(pthrottling->shared_cpu_map);
201 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
202 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
203 }
204 }
205
206 return retval;
207 }
208
209 /*
210 * Update the T-state coordination after the _TSD
211 * data for all cpus is obtained.
212 */
213 void acpi_processor_throttling_init(void)
214 {
215 if (acpi_processor_update_tsd_coord())
216 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
217 "Assume no T-state coordination\n"));
218
219 return;
220 }
221
222 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
223 {
224 struct throttling_tstate *p_tstate = data;
225 struct acpi_processor *pr;
226 unsigned int cpu ;
227 int target_state;
228 struct acpi_processor_limit *p_limit;
229 struct acpi_processor_throttling *p_throttling;
230
231 cpu = p_tstate->cpu;
232 pr = per_cpu(processors, cpu);
233 if (!pr) {
234 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
235 return 0;
236 }
237 if (!pr->flags.throttling) {
238 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
239 "unsupported on CPU %d\n", cpu));
240 return 0;
241 }
242 target_state = p_tstate->target_state;
243 p_throttling = &(pr->throttling);
244 switch (event) {
245 case THROTTLING_PRECHANGE:
246 /*
247 * Prechange event is used to choose one proper t-state,
248 * which meets the limits of thermal, user and _TPC.
249 */
250 p_limit = &pr->limit;
251 if (p_limit->thermal.tx > target_state)
252 target_state = p_limit->thermal.tx;
253 if (p_limit->user.tx > target_state)
254 target_state = p_limit->user.tx;
255 if (pr->throttling_platform_limit > target_state)
256 target_state = pr->throttling_platform_limit;
257 if (target_state >= p_throttling->state_count) {
258 printk(KERN_WARNING
259 "Exceed the limit of T-state \n");
260 target_state = p_throttling->state_count - 1;
261 }
262 p_tstate->target_state = target_state;
263 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
264 "target T-state of CPU %d is T%d\n",
265 cpu, target_state));
266 break;
267 case THROTTLING_POSTCHANGE:
268 /*
269 * Postchange event is only used to update the
270 * T-state flag of acpi_processor_throttling.
271 */
272 p_throttling->state = target_state;
273 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
274 "CPU %d is switched to T%d\n",
275 cpu, target_state));
276 break;
277 default:
278 printk(KERN_WARNING
279 "Unsupported Throttling notifier event\n");
280 break;
281 }
282
283 return 0;
284 }
285
286 /*
287 * _TPC - Throttling Present Capabilities
288 */
289 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
290 {
291 acpi_status status = 0;
292 unsigned long long tpc = 0;
293
294 if (!pr)
295 return -EINVAL;
296
297 if (ignore_tpc)
298 goto end;
299
300 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
301 if (ACPI_FAILURE(status)) {
302 if (status != AE_NOT_FOUND) {
303 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
304 }
305 return -ENODEV;
306 }
307
308 end:
309 pr->throttling_platform_limit = (int)tpc;
310 return 0;
311 }
312
313 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
314 {
315 int result = 0;
316 int throttling_limit;
317 int current_state;
318 struct acpi_processor_limit *limit;
319 int target_state;
320
321 if (ignore_tpc)
322 return 0;
323
324 result = acpi_processor_get_platform_limit(pr);
325 if (result) {
326 /* Throttling Limit is unsupported */
327 return result;
328 }
329
330 throttling_limit = pr->throttling_platform_limit;
331 if (throttling_limit >= pr->throttling.state_count) {
332 /* Uncorrect Throttling Limit */
333 return -EINVAL;
334 }
335
336 current_state = pr->throttling.state;
337 if (current_state > throttling_limit) {
338 /*
339 * The current state can meet the requirement of
340 * _TPC limit. But it is reasonable that OSPM changes
341 * t-states from high to low for better performance.
342 * Of course the limit condition of thermal
343 * and user should be considered.
344 */
345 limit = &pr->limit;
346 target_state = throttling_limit;
347 if (limit->thermal.tx > target_state)
348 target_state = limit->thermal.tx;
349 if (limit->user.tx > target_state)
350 target_state = limit->user.tx;
351 } else if (current_state == throttling_limit) {
352 /*
353 * Unnecessary to change the throttling state
354 */
355 return 0;
356 } else {
357 /*
358 * If the current state is lower than the limit of _TPC, it
359 * will be forced to switch to the throttling state defined
360 * by throttling_platfor_limit.
361 * Because the previous state meets with the limit condition
362 * of thermal and user, it is unnecessary to check it again.
363 */
364 target_state = throttling_limit;
365 }
366 return acpi_processor_set_throttling(pr, target_state, false);
367 }
368
369 /*
370 * _PTC - Processor Throttling Control (and status) register location
371 */
372 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
373 {
374 int result = 0;
375 acpi_status status = 0;
376 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
377 union acpi_object *ptc = NULL;
378 union acpi_object obj = { 0 };
379 struct acpi_processor_throttling *throttling;
380
381 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
382 if (ACPI_FAILURE(status)) {
383 if (status != AE_NOT_FOUND) {
384 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
385 }
386 return -ENODEV;
387 }
388
389 ptc = (union acpi_object *)buffer.pointer;
390 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
391 || (ptc->package.count != 2)) {
392 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
393 result = -EFAULT;
394 goto end;
395 }
396
397 /*
398 * control_register
399 */
400
401 obj = ptc->package.elements[0];
402
403 if ((obj.type != ACPI_TYPE_BUFFER)
404 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
405 || (obj.buffer.pointer == NULL)) {
406 printk(KERN_ERR PREFIX
407 "Invalid _PTC data (control_register)\n");
408 result = -EFAULT;
409 goto end;
410 }
411 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
412 sizeof(struct acpi_ptc_register));
413
414 /*
415 * status_register
416 */
417
418 obj = ptc->package.elements[1];
419
420 if ((obj.type != ACPI_TYPE_BUFFER)
421 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
422 || (obj.buffer.pointer == NULL)) {
423 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
424 result = -EFAULT;
425 goto end;
426 }
427
428 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
429 sizeof(struct acpi_ptc_register));
430
431 throttling = &pr->throttling;
432
433 if ((throttling->control_register.bit_width +
434 throttling->control_register.bit_offset) > 32) {
435 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
436 result = -EFAULT;
437 goto end;
438 }
439
440 if ((throttling->status_register.bit_width +
441 throttling->status_register.bit_offset) > 32) {
442 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
443 result = -EFAULT;
444 goto end;
445 }
446
447 end:
448 kfree(buffer.pointer);
449
450 return result;
451 }
452
453 /*
454 * _TSS - Throttling Supported States
455 */
456 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
457 {
458 int result = 0;
459 acpi_status status = AE_OK;
460 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
461 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
462 struct acpi_buffer state = { 0, NULL };
463 union acpi_object *tss = NULL;
464 int i;
465
466 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
467 if (ACPI_FAILURE(status)) {
468 if (status != AE_NOT_FOUND) {
469 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
470 }
471 return -ENODEV;
472 }
473
474 tss = buffer.pointer;
475 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
476 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
477 result = -EFAULT;
478 goto end;
479 }
480
481 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
482 tss->package.count));
483
484 pr->throttling.state_count = tss->package.count;
485 pr->throttling.states_tss =
486 kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
487 GFP_KERNEL);
488 if (!pr->throttling.states_tss) {
489 result = -ENOMEM;
490 goto end;
491 }
492
493 for (i = 0; i < pr->throttling.state_count; i++) {
494
495 struct acpi_processor_tx_tss *tx =
496 (struct acpi_processor_tx_tss *)&(pr->throttling.
497 states_tss[i]);
498
499 state.length = sizeof(struct acpi_processor_tx_tss);
500 state.pointer = tx;
501
502 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
503
504 status = acpi_extract_package(&(tss->package.elements[i]),
505 &format, &state);
506 if (ACPI_FAILURE(status)) {
507 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
508 result = -EFAULT;
509 kfree(pr->throttling.states_tss);
510 goto end;
511 }
512
513 if (!tx->freqpercentage) {
514 printk(KERN_ERR PREFIX
515 "Invalid _TSS data: freq is zero\n");
516 result = -EFAULT;
517 kfree(pr->throttling.states_tss);
518 goto end;
519 }
520 }
521
522 end:
523 kfree(buffer.pointer);
524
525 return result;
526 }
527
528 /*
529 * _TSD - T-State Dependencies
530 */
531 static int acpi_processor_get_tsd(struct acpi_processor *pr)
532 {
533 int result = 0;
534 acpi_status status = AE_OK;
535 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
536 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
537 struct acpi_buffer state = { 0, NULL };
538 union acpi_object *tsd = NULL;
539 struct acpi_tsd_package *pdomain;
540 struct acpi_processor_throttling *pthrottling;
541
542 pthrottling = &pr->throttling;
543 pthrottling->tsd_valid_flag = 0;
544
545 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
546 if (ACPI_FAILURE(status)) {
547 if (status != AE_NOT_FOUND) {
548 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
549 }
550 return -ENODEV;
551 }
552
553 tsd = buffer.pointer;
554 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
555 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
556 result = -EFAULT;
557 goto end;
558 }
559
560 if (tsd->package.count != 1) {
561 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
562 result = -EFAULT;
563 goto end;
564 }
565
566 pdomain = &(pr->throttling.domain_info);
567
568 state.length = sizeof(struct acpi_tsd_package);
569 state.pointer = pdomain;
570
571 status = acpi_extract_package(&(tsd->package.elements[0]),
572 &format, &state);
573 if (ACPI_FAILURE(status)) {
574 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
575 result = -EFAULT;
576 goto end;
577 }
578
579 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
580 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
581 result = -EFAULT;
582 goto end;
583 }
584
585 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
586 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
587 result = -EFAULT;
588 goto end;
589 }
590
591 pthrottling = &pr->throttling;
592 pthrottling->tsd_valid_flag = 1;
593 pthrottling->shared_type = pdomain->coord_type;
594 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
595 /*
596 * If the coordination type is not defined in ACPI spec,
597 * the tsd_valid_flag will be clear and coordination type
598 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
599 */
600 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
601 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
602 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
603 pthrottling->tsd_valid_flag = 0;
604 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
605 }
606
607 end:
608 kfree(buffer.pointer);
609 return result;
610 }
611
612 /* --------------------------------------------------------------------------
613 Throttling Control
614 -------------------------------------------------------------------------- */
615 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
616 {
617 int state = 0;
618 u32 value = 0;
619 u32 duty_mask = 0;
620 u32 duty_value = 0;
621
622 if (!pr)
623 return -EINVAL;
624
625 if (!pr->flags.throttling)
626 return -ENODEV;
627
628 pr->throttling.state = 0;
629
630 duty_mask = pr->throttling.state_count - 1;
631
632 duty_mask <<= pr->throttling.duty_offset;
633
634 local_irq_disable();
635
636 value = inl(pr->throttling.address);
637
638 /*
639 * Compute the current throttling state when throttling is enabled
640 * (bit 4 is on).
641 */
642 if (value & 0x10) {
643 duty_value = value & duty_mask;
644 duty_value >>= pr->throttling.duty_offset;
645
646 if (duty_value)
647 state = pr->throttling.state_count - duty_value;
648 }
649
650 pr->throttling.state = state;
651
652 local_irq_enable();
653
654 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
655 "Throttling state is T%d (%d%% throttling applied)\n",
656 state, pr->throttling.states[state].performance));
657
658 return 0;
659 }
660
661 #ifdef CONFIG_X86
662 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
663 u64 *value)
664 {
665 struct cpuinfo_x86 *c;
666 u64 msr_high, msr_low;
667 unsigned int cpu;
668 u64 msr = 0;
669 int ret = -1;
670
671 cpu = pr->id;
672 c = &cpu_data(cpu);
673
674 if ((c->x86_vendor != X86_VENDOR_INTEL) ||
675 !cpu_has(c, X86_FEATURE_ACPI)) {
676 printk(KERN_ERR PREFIX
677 "HARDWARE addr space,NOT supported yet\n");
678 } else {
679 msr_low = 0;
680 msr_high = 0;
681 rdmsr_safe(MSR_IA32_THERM_CONTROL,
682 (u32 *)&msr_low , (u32 *) &msr_high);
683 msr = (msr_high << 32) | msr_low;
684 *value = (u64) msr;
685 ret = 0;
686 }
687 return ret;
688 }
689
690 static int acpi_throttling_wrmsr(struct acpi_processor *pr, u64 value)
691 {
692 struct cpuinfo_x86 *c;
693 unsigned int cpu;
694 int ret = -1;
695 u64 msr;
696
697 cpu = pr->id;
698 c = &cpu_data(cpu);
699
700 if ((c->x86_vendor != X86_VENDOR_INTEL) ||
701 !cpu_has(c, X86_FEATURE_ACPI)) {
702 printk(KERN_ERR PREFIX
703 "HARDWARE addr space,NOT supported yet\n");
704 } else {
705 msr = value;
706 wrmsr_safe(MSR_IA32_THERM_CONTROL,
707 msr & 0xffffffff, msr >> 32);
708 ret = 0;
709 }
710 return ret;
711 }
712 #else
713 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
714 u64 *value)
715 {
716 printk(KERN_ERR PREFIX
717 "HARDWARE addr space,NOT supported yet\n");
718 return -1;
719 }
720
721 static int acpi_throttling_wrmsr(struct acpi_processor *pr, u64 value)
722 {
723 printk(KERN_ERR PREFIX
724 "HARDWARE addr space,NOT supported yet\n");
725 return -1;
726 }
727 #endif
728
729 static int acpi_read_throttling_status(struct acpi_processor *pr,
730 u64 *value)
731 {
732 u32 bit_width, bit_offset;
733 u64 ptc_value;
734 u64 ptc_mask;
735 struct acpi_processor_throttling *throttling;
736 int ret = -1;
737
738 throttling = &pr->throttling;
739 switch (throttling->status_register.space_id) {
740 case ACPI_ADR_SPACE_SYSTEM_IO:
741 ptc_value = 0;
742 bit_width = throttling->status_register.bit_width;
743 bit_offset = throttling->status_register.bit_offset;
744
745 acpi_os_read_port((acpi_io_address) throttling->status_register.
746 address, (u32 *) &ptc_value,
747 (u32) (bit_width + bit_offset));
748 ptc_mask = (1 << bit_width) - 1;
749 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
750 ret = 0;
751 break;
752 case ACPI_ADR_SPACE_FIXED_HARDWARE:
753 ret = acpi_throttling_rdmsr(pr, value);
754 break;
755 default:
756 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
757 (u32) (throttling->status_register.space_id));
758 }
759 return ret;
760 }
761
762 static int acpi_write_throttling_state(struct acpi_processor *pr,
763 u64 value)
764 {
765 u32 bit_width, bit_offset;
766 u64 ptc_value;
767 u64 ptc_mask;
768 struct acpi_processor_throttling *throttling;
769 int ret = -1;
770
771 throttling = &pr->throttling;
772 switch (throttling->control_register.space_id) {
773 case ACPI_ADR_SPACE_SYSTEM_IO:
774 bit_width = throttling->control_register.bit_width;
775 bit_offset = throttling->control_register.bit_offset;
776 ptc_mask = (1 << bit_width) - 1;
777 ptc_value = value & ptc_mask;
778
779 acpi_os_write_port((acpi_io_address) throttling->
780 control_register.address,
781 (u32) (ptc_value << bit_offset),
782 (u32) (bit_width + bit_offset));
783 ret = 0;
784 break;
785 case ACPI_ADR_SPACE_FIXED_HARDWARE:
786 ret = acpi_throttling_wrmsr(pr, value);
787 break;
788 default:
789 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
790 (u32) (throttling->control_register.space_id));
791 }
792 return ret;
793 }
794
795 static int acpi_get_throttling_state(struct acpi_processor *pr,
796 u64 value)
797 {
798 int i;
799
800 for (i = 0; i < pr->throttling.state_count; i++) {
801 struct acpi_processor_tx_tss *tx =
802 (struct acpi_processor_tx_tss *)&(pr->throttling.
803 states_tss[i]);
804 if (tx->control == value)
805 return i;
806 }
807 return -1;
808 }
809
810 static int acpi_get_throttling_value(struct acpi_processor *pr,
811 int state, u64 *value)
812 {
813 int ret = -1;
814
815 if (state >= 0 && state <= pr->throttling.state_count) {
816 struct acpi_processor_tx_tss *tx =
817 (struct acpi_processor_tx_tss *)&(pr->throttling.
818 states_tss[state]);
819 *value = tx->control;
820 ret = 0;
821 }
822 return ret;
823 }
824
825 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
826 {
827 int state = 0;
828 int ret;
829 u64 value;
830
831 if (!pr)
832 return -EINVAL;
833
834 if (!pr->flags.throttling)
835 return -ENODEV;
836
837 pr->throttling.state = 0;
838
839 value = 0;
840 ret = acpi_read_throttling_status(pr, &value);
841 if (ret >= 0) {
842 state = acpi_get_throttling_state(pr, value);
843 if (state == -1) {
844 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
845 "Invalid throttling state, reset\n"));
846 state = 0;
847 ret = acpi_processor_set_throttling(pr, state, true);
848 if (ret)
849 return ret;
850 }
851 pr->throttling.state = state;
852 }
853
854 return 0;
855 }
856
857 static int acpi_processor_get_throttling(struct acpi_processor *pr)
858 {
859 cpumask_var_t saved_mask;
860 int ret;
861
862 if (!pr)
863 return -EINVAL;
864
865 if (!pr->flags.throttling)
866 return -ENODEV;
867
868 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
869 return -ENOMEM;
870
871 /*
872 * Migrate task to the cpu pointed by pr.
873 */
874 cpumask_copy(saved_mask, &current->cpus_allowed);
875 /* FIXME: use work_on_cpu() */
876 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
877 ret = pr->throttling.acpi_processor_get_throttling(pr);
878 /* restore the previous state */
879 set_cpus_allowed_ptr(current, saved_mask);
880 free_cpumask_var(saved_mask);
881
882 return ret;
883 }
884
885 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
886 {
887 int i, step;
888
889 if (!pr->throttling.address) {
890 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
891 return -EINVAL;
892 } else if (!pr->throttling.duty_width) {
893 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
894 return -EINVAL;
895 }
896 /* TBD: Support duty_cycle values that span bit 4. */
897 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
898 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
899 return -EINVAL;
900 }
901
902 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
903
904 /*
905 * Compute state values. Note that throttling displays a linear power
906 * performance relationship (at 50% performance the CPU will consume
907 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
908 */
909
910 step = (1000 / pr->throttling.state_count);
911
912 for (i = 0; i < pr->throttling.state_count; i++) {
913 pr->throttling.states[i].performance = 1000 - step * i;
914 pr->throttling.states[i].power = 1000 - step * i;
915 }
916 return 0;
917 }
918
919 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
920 int state, bool force)
921 {
922 u32 value = 0;
923 u32 duty_mask = 0;
924 u32 duty_value = 0;
925
926 if (!pr)
927 return -EINVAL;
928
929 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
930 return -EINVAL;
931
932 if (!pr->flags.throttling)
933 return -ENODEV;
934
935 if (!force && (state == pr->throttling.state))
936 return 0;
937
938 if (state < pr->throttling_platform_limit)
939 return -EPERM;
940 /*
941 * Calculate the duty_value and duty_mask.
942 */
943 if (state) {
944 duty_value = pr->throttling.state_count - state;
945
946 duty_value <<= pr->throttling.duty_offset;
947
948 /* Used to clear all duty_value bits */
949 duty_mask = pr->throttling.state_count - 1;
950
951 duty_mask <<= acpi_gbl_FADT.duty_offset;
952 duty_mask = ~duty_mask;
953 }
954
955 local_irq_disable();
956
957 /*
958 * Disable throttling by writing a 0 to bit 4. Note that we must
959 * turn it off before you can change the duty_value.
960 */
961 value = inl(pr->throttling.address);
962 if (value & 0x10) {
963 value &= 0xFFFFFFEF;
964 outl(value, pr->throttling.address);
965 }
966
967 /*
968 * Write the new duty_value and then enable throttling. Note
969 * that a state value of 0 leaves throttling disabled.
970 */
971 if (state) {
972 value &= duty_mask;
973 value |= duty_value;
974 outl(value, pr->throttling.address);
975
976 value |= 0x00000010;
977 outl(value, pr->throttling.address);
978 }
979
980 pr->throttling.state = state;
981
982 local_irq_enable();
983
984 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
985 "Throttling state set to T%d (%d%%)\n", state,
986 (pr->throttling.states[state].performance ? pr->
987 throttling.states[state].performance / 10 : 0)));
988
989 return 0;
990 }
991
992 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
993 int state, bool force)
994 {
995 int ret;
996 u64 value;
997
998 if (!pr)
999 return -EINVAL;
1000
1001 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1002 return -EINVAL;
1003
1004 if (!pr->flags.throttling)
1005 return -ENODEV;
1006
1007 if (!force && (state == pr->throttling.state))
1008 return 0;
1009
1010 if (state < pr->throttling_platform_limit)
1011 return -EPERM;
1012
1013 value = 0;
1014 ret = acpi_get_throttling_value(pr, state, &value);
1015 if (ret >= 0) {
1016 acpi_write_throttling_state(pr, value);
1017 pr->throttling.state = state;
1018 }
1019
1020 return 0;
1021 }
1022
1023 int acpi_processor_set_throttling(struct acpi_processor *pr,
1024 int state, bool force)
1025 {
1026 cpumask_var_t saved_mask;
1027 int ret = 0;
1028 unsigned int i;
1029 struct acpi_processor *match_pr;
1030 struct acpi_processor_throttling *p_throttling;
1031 struct throttling_tstate t_state;
1032 cpumask_var_t online_throttling_cpus;
1033
1034 if (!pr)
1035 return -EINVAL;
1036
1037 if (!pr->flags.throttling)
1038 return -ENODEV;
1039
1040 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1041 return -EINVAL;
1042
1043 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1044 return -ENOMEM;
1045
1046 if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1047 free_cpumask_var(saved_mask);
1048 return -ENOMEM;
1049 }
1050
1051 cpumask_copy(saved_mask, &current->cpus_allowed);
1052 t_state.target_state = state;
1053 p_throttling = &(pr->throttling);
1054 cpumask_and(online_throttling_cpus, cpu_online_mask,
1055 p_throttling->shared_cpu_map);
1056 /*
1057 * The throttling notifier will be called for every
1058 * affected cpu in order to get one proper T-state.
1059 * The notifier event is THROTTLING_PRECHANGE.
1060 */
1061 for_each_cpu(i, online_throttling_cpus) {
1062 t_state.cpu = i;
1063 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1064 &t_state);
1065 }
1066 /*
1067 * The function of acpi_processor_set_throttling will be called
1068 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1069 * it is necessary to call it for every affected cpu. Otherwise
1070 * it can be called only for the cpu pointed by pr.
1071 */
1072 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1073 /* FIXME: use work_on_cpu() */
1074 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
1075 ret = p_throttling->acpi_processor_set_throttling(pr,
1076 t_state.target_state, force);
1077 } else {
1078 /*
1079 * When the T-state coordination is SW_ALL or HW_ALL,
1080 * it is necessary to set T-state for every affected
1081 * cpus.
1082 */
1083 for_each_cpu(i, online_throttling_cpus) {
1084 match_pr = per_cpu(processors, i);
1085 /*
1086 * If the pointer is invalid, we will report the
1087 * error message and continue.
1088 */
1089 if (!match_pr) {
1090 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1091 "Invalid Pointer for CPU %d\n", i));
1092 continue;
1093 }
1094 /*
1095 * If the throttling control is unsupported on CPU i,
1096 * we will report the error message and continue.
1097 */
1098 if (!match_pr->flags.throttling) {
1099 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1100 "Throttling Controll is unsupported "
1101 "on CPU %d\n", i));
1102 continue;
1103 }
1104 t_state.cpu = i;
1105 /* FIXME: use work_on_cpu() */
1106 set_cpus_allowed_ptr(current, cpumask_of(i));
1107 ret = match_pr->throttling.
1108 acpi_processor_set_throttling(
1109 match_pr, t_state.target_state, force);
1110 }
1111 }
1112 /*
1113 * After the set_throttling is called, the
1114 * throttling notifier is called for every
1115 * affected cpu to update the T-states.
1116 * The notifier event is THROTTLING_POSTCHANGE
1117 */
1118 for_each_cpu(i, online_throttling_cpus) {
1119 t_state.cpu = i;
1120 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1121 &t_state);
1122 }
1123 /* restore the previous state */
1124 /* FIXME: use work_on_cpu() */
1125 set_cpus_allowed_ptr(current, saved_mask);
1126 free_cpumask_var(online_throttling_cpus);
1127 free_cpumask_var(saved_mask);
1128 return ret;
1129 }
1130
1131 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1132 {
1133 int result = 0;
1134 struct acpi_processor_throttling *pthrottling;
1135
1136 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1137 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1138 pr->throttling.address,
1139 pr->throttling.duty_offset,
1140 pr->throttling.duty_width));
1141
1142 /*
1143 * Evaluate _PTC, _TSS and _TPC
1144 * They must all be present or none of them can be used.
1145 */
1146 if (acpi_processor_get_throttling_control(pr) ||
1147 acpi_processor_get_throttling_states(pr) ||
1148 acpi_processor_get_platform_limit(pr))
1149 {
1150 pr->throttling.acpi_processor_get_throttling =
1151 &acpi_processor_get_throttling_fadt;
1152 pr->throttling.acpi_processor_set_throttling =
1153 &acpi_processor_set_throttling_fadt;
1154 if (acpi_processor_get_fadt_info(pr))
1155 return 0;
1156 } else {
1157 pr->throttling.acpi_processor_get_throttling =
1158 &acpi_processor_get_throttling_ptc;
1159 pr->throttling.acpi_processor_set_throttling =
1160 &acpi_processor_set_throttling_ptc;
1161 }
1162
1163 /*
1164 * If TSD package for one CPU can't be parsed successfully, it means
1165 * that this CPU will have no coordination with other CPUs.
1166 */
1167 if (acpi_processor_get_tsd(pr)) {
1168 pthrottling = &pr->throttling;
1169 pthrottling->tsd_valid_flag = 0;
1170 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1171 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1172 }
1173
1174 /*
1175 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1176 * This shouldn't be an issue as few (if any) mobile systems ever
1177 * used this part.
1178 */
1179 if (errata.piix4.throttle) {
1180 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1181 "Throttling not supported on PIIX4 A- or B-step\n"));
1182 return 0;
1183 }
1184
1185 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1186 pr->throttling.state_count));
1187
1188 pr->flags.throttling = 1;
1189
1190 /*
1191 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1192 * thermal) decide to lower performance if it so chooses, but for now
1193 * we'll crank up the speed.
1194 */
1195
1196 result = acpi_processor_get_throttling(pr);
1197 if (result)
1198 goto end;
1199
1200 if (pr->throttling.state) {
1201 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1202 "Disabling throttling (was T%d)\n",
1203 pr->throttling.state));
1204 result = acpi_processor_set_throttling(pr, 0, false);
1205 if (result)
1206 goto end;
1207 }
1208
1209 end:
1210 if (result)
1211 pr->flags.throttling = 0;
1212
1213 return result;
1214 }
1215
1216 /* proc interface */
1217 #ifdef CONFIG_ACPI_PROCFS
1218 static int acpi_processor_throttling_seq_show(struct seq_file *seq,
1219 void *offset)
1220 {
1221 struct acpi_processor *pr = seq->private;
1222 int i = 0;
1223 int result = 0;
1224
1225 if (!pr)
1226 goto end;
1227
1228 if (!(pr->throttling.state_count > 0)) {
1229 seq_puts(seq, "<not supported>\n");
1230 goto end;
1231 }
1232
1233 result = acpi_processor_get_throttling(pr);
1234
1235 if (result) {
1236 seq_puts(seq,
1237 "Could not determine current throttling state.\n");
1238 goto end;
1239 }
1240
1241 seq_printf(seq, "state count: %d\n"
1242 "active state: T%d\n"
1243 "state available: T%d to T%d\n",
1244 pr->throttling.state_count, pr->throttling.state,
1245 pr->throttling_platform_limit,
1246 pr->throttling.state_count - 1);
1247
1248 seq_puts(seq, "states:\n");
1249 if (pr->throttling.acpi_processor_get_throttling ==
1250 acpi_processor_get_throttling_fadt) {
1251 for (i = 0; i < pr->throttling.state_count; i++)
1252 seq_printf(seq, " %cT%d: %02d%%\n",
1253 (i == pr->throttling.state ? '*' : ' '), i,
1254 (pr->throttling.states[i].performance ? pr->
1255 throttling.states[i].performance / 10 : 0));
1256 } else {
1257 for (i = 0; i < pr->throttling.state_count; i++)
1258 seq_printf(seq, " %cT%d: %02d%%\n",
1259 (i == pr->throttling.state ? '*' : ' '), i,
1260 (int)pr->throttling.states_tss[i].
1261 freqpercentage);
1262 }
1263
1264 end:
1265 return 0;
1266 }
1267
1268 static int acpi_processor_throttling_open_fs(struct inode *inode,
1269 struct file *file)
1270 {
1271 return single_open(file, acpi_processor_throttling_seq_show,
1272 PDE(inode)->data);
1273 }
1274
1275 static ssize_t acpi_processor_write_throttling(struct file *file,
1276 const char __user * buffer,
1277 size_t count, loff_t * data)
1278 {
1279 int result = 0;
1280 struct seq_file *m = file->private_data;
1281 struct acpi_processor *pr = m->private;
1282 char state_string[5] = "";
1283 char *charp = NULL;
1284 size_t state_val = 0;
1285 char tmpbuf[5] = "";
1286
1287 if (!pr || (count > sizeof(state_string) - 1))
1288 return -EINVAL;
1289
1290 if (copy_from_user(state_string, buffer, count))
1291 return -EFAULT;
1292
1293 state_string[count] = '\0';
1294 if ((count > 0) && (state_string[count-1] == '\n'))
1295 state_string[count-1] = '\0';
1296
1297 charp = state_string;
1298 if ((state_string[0] == 't') || (state_string[0] == 'T'))
1299 charp++;
1300
1301 state_val = simple_strtoul(charp, NULL, 0);
1302 if (state_val >= pr->throttling.state_count)
1303 return -EINVAL;
1304
1305 snprintf(tmpbuf, 5, "%zu", state_val);
1306
1307 if (strcmp(tmpbuf, charp) != 0)
1308 return -EINVAL;
1309
1310 result = acpi_processor_set_throttling(pr, state_val, false);
1311 if (result)
1312 return result;
1313
1314 return count;
1315 }
1316
1317 const struct file_operations acpi_processor_throttling_fops = {
1318 .owner = THIS_MODULE,
1319 .open = acpi_processor_throttling_open_fs,
1320 .read = seq_read,
1321 .write = acpi_processor_write_throttling,
1322 .llseek = seq_lseek,
1323 .release = single_release,
1324 };
1325 #endif