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ptrace: annotate lock context change on exit_ptrace()
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / acpi / processor_throttling.c
blobff3632717c5140bd7c8692e0055b74681ece037c
1 /*
2 * processor_throttling.c - Throttling submodule of the ACPI processor driver
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * - Added processor hotplug support
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or (at
15 * your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 *
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 */
28
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/slab.h>
32 #include <linux/init.h>
33 #include <linux/sched.h>
34 #include <linux/cpufreq.h>
35 #ifdef CONFIG_ACPI_PROCFS
36 #include <linux/proc_fs.h>
37 #include <linux/seq_file.h>
38 #endif
39
40 #include <asm/io.h>
41 #include <asm/uaccess.h>
42
43 #include <acpi/acpi_bus.h>
44 #include <acpi/acpi_drivers.h>
45 #include <acpi/processor.h>
46
47 #define PREFIX "ACPI: "
48
49 #define ACPI_PROCESSOR_CLASS "processor"
50 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
51 ACPI_MODULE_NAME("processor_throttling");
52
53 /* ignore_tpc:
54 * 0 -> acpi processor driver doesn't ignore _TPC values
55 * 1 -> acpi processor driver ignores _TPC values
56 */
57 static int ignore_tpc;
58 module_param(ignore_tpc, int, 0644);
59 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
60
61 struct throttling_tstate {
62 unsigned int cpu; /* cpu nr */
63 int target_state; /* target T-state */
64 };
65
66 #define THROTTLING_PRECHANGE (1)
67 #define THROTTLING_POSTCHANGE (2)
68
69 static int acpi_processor_get_throttling(struct acpi_processor *pr);
70 int acpi_processor_set_throttling(struct acpi_processor *pr,
71 int state, bool force);
72
73 static int acpi_processor_update_tsd_coord(void)
74 {
75 int count, count_target;
76 int retval = 0;
77 unsigned int i, j;
78 cpumask_var_t covered_cpus;
79 struct acpi_processor *pr, *match_pr;
80 struct acpi_tsd_package *pdomain, *match_pdomain;
81 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
82
83 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
84 return -ENOMEM;
85
86 /*
87 * Now that we have _TSD data from all CPUs, lets setup T-state
88 * coordination between all CPUs.
89 */
90 for_each_possible_cpu(i) {
91 pr = per_cpu(processors, i);
92 if (!pr)
93 continue;
94
95 /* Basic validity check for domain info */
96 pthrottling = &(pr->throttling);
97
98 /*
99 * If tsd package for one cpu is invalid, the coordination
100 * among all CPUs is thought as invalid.
101 * Maybe it is ugly.
102 */
103 if (!pthrottling->tsd_valid_flag) {
104 retval = -EINVAL;
105 break;
106 }
107 }
108 if (retval)
109 goto err_ret;
110
111 for_each_possible_cpu(i) {
112 pr = per_cpu(processors, i);
113 if (!pr)
114 continue;
115
116 if (cpumask_test_cpu(i, covered_cpus))
117 continue;
118 pthrottling = &pr->throttling;
119
120 pdomain = &(pthrottling->domain_info);
121 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
122 cpumask_set_cpu(i, covered_cpus);
123 /*
124 * If the number of processor in the TSD domain is 1, it is
125 * unnecessary to parse the coordination for this CPU.
126 */
127 if (pdomain->num_processors <= 1)
128 continue;
129
130 /* Validate the Domain info */
131 count_target = pdomain->num_processors;
132 count = 1;
133
134 for_each_possible_cpu(j) {
135 if (i == j)
136 continue;
137
138 match_pr = per_cpu(processors, j);
139 if (!match_pr)
140 continue;
141
142 match_pthrottling = &(match_pr->throttling);
143 match_pdomain = &(match_pthrottling->domain_info);
144 if (match_pdomain->domain != pdomain->domain)
145 continue;
146
147 /* Here i and j are in the same domain.
148 * If two TSD packages have the same domain, they
149 * should have the same num_porcessors and
150 * coordination type. Otherwise it will be regarded
151 * as illegal.
152 */
153 if (match_pdomain->num_processors != count_target) {
154 retval = -EINVAL;
155 goto err_ret;
156 }
157
158 if (pdomain->coord_type != match_pdomain->coord_type) {
159 retval = -EINVAL;
160 goto err_ret;
161 }
162
163 cpumask_set_cpu(j, covered_cpus);
164 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
165 count++;
166 }
167 for_each_possible_cpu(j) {
168 if (i == j)
169 continue;
170
171 match_pr = per_cpu(processors, j);
172 if (!match_pr)
173 continue;
174
175 match_pthrottling = &(match_pr->throttling);
176 match_pdomain = &(match_pthrottling->domain_info);
177 if (match_pdomain->domain != pdomain->domain)
178 continue;
179
180 /*
181 * If some CPUS have the same domain, they
182 * will have the same shared_cpu_map.
183 */
184 cpumask_copy(match_pthrottling->shared_cpu_map,
185 pthrottling->shared_cpu_map);
186 }
187 }
188
189 err_ret:
190 free_cpumask_var(covered_cpus);
191
192 for_each_possible_cpu(i) {
193 pr = per_cpu(processors, i);
194 if (!pr)
195 continue;
196
197 /*
198 * Assume no coordination on any error parsing domain info.
199 * The coordination type will be forced as SW_ALL.
200 */
201 if (retval) {
202 pthrottling = &(pr->throttling);
203 cpumask_clear(pthrottling->shared_cpu_map);
204 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
205 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
206 }
207 }
208
209 return retval;
210 }
211
212 /*
213 * Update the T-state coordination after the _TSD
214 * data for all cpus is obtained.
215 */
216 void acpi_processor_throttling_init(void)
217 {
218 if (acpi_processor_update_tsd_coord())
219 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
220 "Assume no T-state coordination\n"));
221
222 return;
223 }
224
225 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
226 {
227 struct throttling_tstate *p_tstate = data;
228 struct acpi_processor *pr;
229 unsigned int cpu ;
230 int target_state;
231 struct acpi_processor_limit *p_limit;
232 struct acpi_processor_throttling *p_throttling;
233
234 cpu = p_tstate->cpu;
235 pr = per_cpu(processors, cpu);
236 if (!pr) {
237 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
238 return 0;
239 }
240 if (!pr->flags.throttling) {
241 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
242 "unsupported on CPU %d\n", cpu));
243 return 0;
244 }
245 target_state = p_tstate->target_state;
246 p_throttling = &(pr->throttling);
247 switch (event) {
248 case THROTTLING_PRECHANGE:
249 /*
250 * Prechange event is used to choose one proper t-state,
251 * which meets the limits of thermal, user and _TPC.
252 */
253 p_limit = &pr->limit;
254 if (p_limit->thermal.tx > target_state)
255 target_state = p_limit->thermal.tx;
256 if (p_limit->user.tx > target_state)
257 target_state = p_limit->user.tx;
258 if (pr->throttling_platform_limit > target_state)
259 target_state = pr->throttling_platform_limit;
260 if (target_state >= p_throttling->state_count) {
261 printk(KERN_WARNING
262 "Exceed the limit of T-state \n");
263 target_state = p_throttling->state_count - 1;
264 }
265 p_tstate->target_state = target_state;
266 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
267 "target T-state of CPU %d is T%d\n",
268 cpu, target_state));
269 break;
270 case THROTTLING_POSTCHANGE:
271 /*
272 * Postchange event is only used to update the
273 * T-state flag of acpi_processor_throttling.
274 */
275 p_throttling->state = target_state;
276 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
277 "CPU %d is switched to T%d\n",
278 cpu, target_state));
279 break;
280 default:
281 printk(KERN_WARNING
282 "Unsupported Throttling notifier event\n");
283 break;
284 }
285
286 return 0;
287 }
288
289 /*
290 * _TPC - Throttling Present Capabilities
291 */
292 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
293 {
294 acpi_status status = 0;
295 unsigned long long tpc = 0;
296
297 if (!pr)
298 return -EINVAL;
299
300 if (ignore_tpc)
301 goto end;
302
303 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
304 if (ACPI_FAILURE(status)) {
305 if (status != AE_NOT_FOUND) {
306 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
307 }
308 return -ENODEV;
309 }
310
311 end:
312 pr->throttling_platform_limit = (int)tpc;
313 return 0;
314 }
315
316 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
317 {
318 int result = 0;
319 int throttling_limit;
320 int current_state;
321 struct acpi_processor_limit *limit;
322 int target_state;
323
324 if (ignore_tpc)
325 return 0;
326
327 result = acpi_processor_get_platform_limit(pr);
328 if (result) {
329 /* Throttling Limit is unsupported */
330 return result;
331 }
332
333 throttling_limit = pr->throttling_platform_limit;
334 if (throttling_limit >= pr->throttling.state_count) {
335 /* Uncorrect Throttling Limit */
336 return -EINVAL;
337 }
338
339 current_state = pr->throttling.state;
340 if (current_state > throttling_limit) {
341 /*
342 * The current state can meet the requirement of
343 * _TPC limit. But it is reasonable that OSPM changes
344 * t-states from high to low for better performance.
345 * Of course the limit condition of thermal
346 * and user should be considered.
347 */
348 limit = &pr->limit;
349 target_state = throttling_limit;
350 if (limit->thermal.tx > target_state)
351 target_state = limit->thermal.tx;
352 if (limit->user.tx > target_state)
353 target_state = limit->user.tx;
354 } else if (current_state == throttling_limit) {
355 /*
356 * Unnecessary to change the throttling state
357 */
358 return 0;
359 } else {
360 /*
361 * If the current state is lower than the limit of _TPC, it
362 * will be forced to switch to the throttling state defined
363 * by throttling_platfor_limit.
364 * Because the previous state meets with the limit condition
365 * of thermal and user, it is unnecessary to check it again.
366 */
367 target_state = throttling_limit;
368 }
369 return acpi_processor_set_throttling(pr, target_state, false);
370 }
371
372 /*
373 * _PTC - Processor Throttling Control (and status) register location
374 */
375 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
376 {
377 int result = 0;
378 acpi_status status = 0;
379 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
380 union acpi_object *ptc = NULL;
381 union acpi_object obj = { 0 };
382 struct acpi_processor_throttling *throttling;
383
384 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
385 if (ACPI_FAILURE(status)) {
386 if (status != AE_NOT_FOUND) {
387 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
388 }
389 return -ENODEV;
390 }
391
392 ptc = (union acpi_object *)buffer.pointer;
393 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
394 || (ptc->package.count != 2)) {
395 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
396 result = -EFAULT;
397 goto end;
398 }
399
400 /*
401 * control_register
402 */
403
404 obj = ptc->package.elements[0];
405
406 if ((obj.type != ACPI_TYPE_BUFFER)
407 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
408 || (obj.buffer.pointer == NULL)) {
409 printk(KERN_ERR PREFIX
410 "Invalid _PTC data (control_register)\n");
411 result = -EFAULT;
412 goto end;
413 }
414 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
415 sizeof(struct acpi_ptc_register));
416
417 /*
418 * status_register
419 */
420
421 obj = ptc->package.elements[1];
422
423 if ((obj.type != ACPI_TYPE_BUFFER)
424 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
425 || (obj.buffer.pointer == NULL)) {
426 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
427 result = -EFAULT;
428 goto end;
429 }
430
431 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
432 sizeof(struct acpi_ptc_register));
433
434 throttling = &pr->throttling;
435
436 if ((throttling->control_register.bit_width +
437 throttling->control_register.bit_offset) > 32) {
438 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
439 result = -EFAULT;
440 goto end;
441 }
442
443 if ((throttling->status_register.bit_width +
444 throttling->status_register.bit_offset) > 32) {
445 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
446 result = -EFAULT;
447 goto end;
448 }
449
450 end:
451 kfree(buffer.pointer);
452
453 return result;
454 }
455
456 /*
457 * _TSS - Throttling Supported States
458 */
459 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
460 {
461 int result = 0;
462 acpi_status status = AE_OK;
463 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
464 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
465 struct acpi_buffer state = { 0, NULL };
466 union acpi_object *tss = NULL;
467 int i;
468
469 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
470 if (ACPI_FAILURE(status)) {
471 if (status != AE_NOT_FOUND) {
472 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
473 }
474 return -ENODEV;
475 }
476
477 tss = buffer.pointer;
478 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
479 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
480 result = -EFAULT;
481 goto end;
482 }
483
484 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
485 tss->package.count));
486
487 pr->throttling.state_count = tss->package.count;
488 pr->throttling.states_tss =
489 kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
490 GFP_KERNEL);
491 if (!pr->throttling.states_tss) {
492 result = -ENOMEM;
493 goto end;
494 }
495
496 for (i = 0; i < pr->throttling.state_count; i++) {
497
498 struct acpi_processor_tx_tss *tx =
499 (struct acpi_processor_tx_tss *)&(pr->throttling.
500 states_tss[i]);
501
502 state.length = sizeof(struct acpi_processor_tx_tss);
503 state.pointer = tx;
504
505 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
506
507 status = acpi_extract_package(&(tss->package.elements[i]),
508 &format, &state);
509 if (ACPI_FAILURE(status)) {
510 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
511 result = -EFAULT;
512 kfree(pr->throttling.states_tss);
513 goto end;
514 }
515
516 if (!tx->freqpercentage) {
517 printk(KERN_ERR PREFIX
518 "Invalid _TSS data: freq is zero\n");
519 result = -EFAULT;
520 kfree(pr->throttling.states_tss);
521 goto end;
522 }
523 }
524
525 end:
526 kfree(buffer.pointer);
527
528 return result;
529 }
530
531 /*
532 * _TSD - T-State Dependencies
533 */
534 static int acpi_processor_get_tsd(struct acpi_processor *pr)
535 {
536 int result = 0;
537 acpi_status status = AE_OK;
538 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
539 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
540 struct acpi_buffer state = { 0, NULL };
541 union acpi_object *tsd = NULL;
542 struct acpi_tsd_package *pdomain;
543 struct acpi_processor_throttling *pthrottling;
544
545 pthrottling = &pr->throttling;
546 pthrottling->tsd_valid_flag = 0;
547
548 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
549 if (ACPI_FAILURE(status)) {
550 if (status != AE_NOT_FOUND) {
551 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
552 }
553 return -ENODEV;
554 }
555
556 tsd = buffer.pointer;
557 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
558 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
559 result = -EFAULT;
560 goto end;
561 }
562
563 if (tsd->package.count != 1) {
564 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
565 result = -EFAULT;
566 goto end;
567 }
568
569 pdomain = &(pr->throttling.domain_info);
570
571 state.length = sizeof(struct acpi_tsd_package);
572 state.pointer = pdomain;
573
574 status = acpi_extract_package(&(tsd->package.elements[0]),
575 &format, &state);
576 if (ACPI_FAILURE(status)) {
577 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
578 result = -EFAULT;
579 goto end;
580 }
581
582 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
583 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
584 result = -EFAULT;
585 goto end;
586 }
587
588 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
589 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
590 result = -EFAULT;
591 goto end;
592 }
593
594 pthrottling = &pr->throttling;
595 pthrottling->tsd_valid_flag = 1;
596 pthrottling->shared_type = pdomain->coord_type;
597 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
598 /*
599 * If the coordination type is not defined in ACPI spec,
600 * the tsd_valid_flag will be clear and coordination type
601 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
602 */
603 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
604 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
605 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
606 pthrottling->tsd_valid_flag = 0;
607 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
608 }
609
610 end:
611 kfree(buffer.pointer);
612 return result;
613 }
614
615 /* --------------------------------------------------------------------------
616 Throttling Control
617 -------------------------------------------------------------------------- */
618 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
619 {
620 int state = 0;
621 u32 value = 0;
622 u32 duty_mask = 0;
623 u32 duty_value = 0;
624
625 if (!pr)
626 return -EINVAL;
627
628 if (!pr->flags.throttling)
629 return -ENODEV;
630
631 pr->throttling.state = 0;
632
633 duty_mask = pr->throttling.state_count - 1;
634
635 duty_mask <<= pr->throttling.duty_offset;
636
637 local_irq_disable();
638
639 value = inl(pr->throttling.address);
640
641 /*
642 * Compute the current throttling state when throttling is enabled
643 * (bit 4 is on).
644 */
645 if (value & 0x10) {
646 duty_value = value & duty_mask;
647 duty_value >>= pr->throttling.duty_offset;
648
649 if (duty_value)
650 state = pr->throttling.state_count - duty_value;
651 }
652
653 pr->throttling.state = state;
654
655 local_irq_enable();
656
657 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
658 "Throttling state is T%d (%d%% throttling applied)\n",
659 state, pr->throttling.states[state].performance));
660
661 return 0;
662 }
663
664 #ifdef CONFIG_X86
665 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
666 u64 *value)
667 {
668 struct cpuinfo_x86 *c;
669 u64 msr_high, msr_low;
670 unsigned int cpu;
671 u64 msr = 0;
672 int ret = -1;
673
674 cpu = pr->id;
675 c = &cpu_data(cpu);
676
677 if ((c->x86_vendor != X86_VENDOR_INTEL) ||
678 !cpu_has(c, X86_FEATURE_ACPI)) {
679 printk(KERN_ERR PREFIX
680 "HARDWARE addr space,NOT supported yet\n");
681 } else {
682 msr_low = 0;
683 msr_high = 0;
684 rdmsr_safe(MSR_IA32_THERM_CONTROL,
685 (u32 *)&msr_low , (u32 *) &msr_high);
686 msr = (msr_high << 32) | msr_low;
687 *value = (u64) msr;
688 ret = 0;
689 }
690 return ret;
691 }
692
693 static int acpi_throttling_wrmsr(struct acpi_processor *pr, u64 value)
694 {
695 struct cpuinfo_x86 *c;
696 unsigned int cpu;
697 int ret = -1;
698 u64 msr;
699
700 cpu = pr->id;
701 c = &cpu_data(cpu);
702
703 if ((c->x86_vendor != X86_VENDOR_INTEL) ||
704 !cpu_has(c, X86_FEATURE_ACPI)) {
705 printk(KERN_ERR PREFIX
706 "HARDWARE addr space,NOT supported yet\n");
707 } else {
708 msr = value;
709 wrmsr_safe(MSR_IA32_THERM_CONTROL,
710 msr & 0xffffffff, msr >> 32);
711 ret = 0;
712 }
713 return ret;
714 }
715 #else
716 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
717 u64 *value)
718 {
719 printk(KERN_ERR PREFIX
720 "HARDWARE addr space,NOT supported yet\n");
721 return -1;
722 }
723
724 static int acpi_throttling_wrmsr(struct acpi_processor *pr, u64 value)
725 {
726 printk(KERN_ERR PREFIX
727 "HARDWARE addr space,NOT supported yet\n");
728 return -1;
729 }
730 #endif
731
732 static int acpi_read_throttling_status(struct acpi_processor *pr,
733 u64 *value)
734 {
735 u32 bit_width, bit_offset;
736 u64 ptc_value;
737 u64 ptc_mask;
738 struct acpi_processor_throttling *throttling;
739 int ret = -1;
740
741 throttling = &pr->throttling;
742 switch (throttling->status_register.space_id) {
743 case ACPI_ADR_SPACE_SYSTEM_IO:
744 ptc_value = 0;
745 bit_width = throttling->status_register.bit_width;
746 bit_offset = throttling->status_register.bit_offset;
747
748 acpi_os_read_port((acpi_io_address) throttling->status_register.
749 address, (u32 *) &ptc_value,
750 (u32) (bit_width + bit_offset));
751 ptc_mask = (1 << bit_width) - 1;
752 *value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
753 ret = 0;
754 break;
755 case ACPI_ADR_SPACE_FIXED_HARDWARE:
756 ret = acpi_throttling_rdmsr(pr, value);
757 break;
758 default:
759 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
760 (u32) (throttling->status_register.space_id));
761 }
762 return ret;
763 }
764
765 static int acpi_write_throttling_state(struct acpi_processor *pr,
766 u64 value)
767 {
768 u32 bit_width, bit_offset;
769 u64 ptc_value;
770 u64 ptc_mask;
771 struct acpi_processor_throttling *throttling;
772 int ret = -1;
773
774 throttling = &pr->throttling;
775 switch (throttling->control_register.space_id) {
776 case ACPI_ADR_SPACE_SYSTEM_IO:
777 bit_width = throttling->control_register.bit_width;
778 bit_offset = throttling->control_register.bit_offset;
779 ptc_mask = (1 << bit_width) - 1;
780 ptc_value = value & ptc_mask;
781
782 acpi_os_write_port((acpi_io_address) throttling->
783 control_register.address,
784 (u32) (ptc_value << bit_offset),
785 (u32) (bit_width + bit_offset));
786 ret = 0;
787 break;
788 case ACPI_ADR_SPACE_FIXED_HARDWARE:
789 ret = acpi_throttling_wrmsr(pr, value);
790 break;
791 default:
792 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
793 (u32) (throttling->control_register.space_id));
794 }
795 return ret;
796 }
797
798 static int acpi_get_throttling_state(struct acpi_processor *pr,
799 u64 value)
800 {
801 int i;
802
803 for (i = 0; i < pr->throttling.state_count; i++) {
804 struct acpi_processor_tx_tss *tx =
805 (struct acpi_processor_tx_tss *)&(pr->throttling.
806 states_tss[i]);
807 if (tx->control == value)
808 return i;
809 }
810 return -1;
811 }
812
813 static int acpi_get_throttling_value(struct acpi_processor *pr,
814 int state, u64 *value)
815 {
816 int ret = -1;
817
818 if (state >= 0 && state <= pr->throttling.state_count) {
819 struct acpi_processor_tx_tss *tx =
820 (struct acpi_processor_tx_tss *)&(pr->throttling.
821 states_tss[state]);
822 *value = tx->control;
823 ret = 0;
824 }
825 return ret;
826 }
827
828 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
829 {
830 int state = 0;
831 int ret;
832 u64 value;
833
834 if (!pr)
835 return -EINVAL;
836
837 if (!pr->flags.throttling)
838 return -ENODEV;
839
840 pr->throttling.state = 0;
841
842 value = 0;
843 ret = acpi_read_throttling_status(pr, &value);
844 if (ret >= 0) {
845 state = acpi_get_throttling_state(pr, value);
846 if (state == -1) {
847 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
848 "Invalid throttling state, reset\n"));
849 state = 0;
850 ret = acpi_processor_set_throttling(pr, state, true);
851 if (ret)
852 return ret;
853 }
854 pr->throttling.state = state;
855 }
856
857 return 0;
858 }
859
860 static int acpi_processor_get_throttling(struct acpi_processor *pr)
861 {
862 cpumask_var_t saved_mask;
863 int ret;
864
865 if (!pr)
866 return -EINVAL;
867
868 if (!pr->flags.throttling)
869 return -ENODEV;
870
871 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
872 return -ENOMEM;
873
874 /*
875 * Migrate task to the cpu pointed by pr.
876 */
877 cpumask_copy(saved_mask, &current->cpus_allowed);
878 /* FIXME: use work_on_cpu() */
879 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
880 ret = pr->throttling.acpi_processor_get_throttling(pr);
881 /* restore the previous state */
882 set_cpus_allowed_ptr(current, saved_mask);
883 free_cpumask_var(saved_mask);
884
885 return ret;
886 }
887
888 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
889 {
890 int i, step;
891
892 if (!pr->throttling.address) {
893 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
894 return -EINVAL;
895 } else if (!pr->throttling.duty_width) {
896 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
897 return -EINVAL;
898 }
899 /* TBD: Support duty_cycle values that span bit 4. */
900 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
901 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
902 return -EINVAL;
903 }
904
905 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
906
907 /*
908 * Compute state values. Note that throttling displays a linear power
909 * performance relationship (at 50% performance the CPU will consume
910 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
911 */
912
913 step = (1000 / pr->throttling.state_count);
914
915 for (i = 0; i < pr->throttling.state_count; i++) {
916 pr->throttling.states[i].performance = 1000 - step * i;
917 pr->throttling.states[i].power = 1000 - step * i;
918 }
919 return 0;
920 }
921
922 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
923 int state, bool force)
924 {
925 u32 value = 0;
926 u32 duty_mask = 0;
927 u32 duty_value = 0;
928
929 if (!pr)
930 return -EINVAL;
931
932 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
933 return -EINVAL;
934
935 if (!pr->flags.throttling)
936 return -ENODEV;
937
938 if (!force && (state == pr->throttling.state))
939 return 0;
940
941 if (state < pr->throttling_platform_limit)
942 return -EPERM;
943 /*
944 * Calculate the duty_value and duty_mask.
945 */
946 if (state) {
947 duty_value = pr->throttling.state_count - state;
948
949 duty_value <<= pr->throttling.duty_offset;
950
951 /* Used to clear all duty_value bits */
952 duty_mask = pr->throttling.state_count - 1;
953
954 duty_mask <<= acpi_gbl_FADT.duty_offset;
955 duty_mask = ~duty_mask;
956 }
957
958 local_irq_disable();
959
960 /*
961 * Disable throttling by writing a 0 to bit 4. Note that we must
962 * turn it off before you can change the duty_value.
963 */
964 value = inl(pr->throttling.address);
965 if (value & 0x10) {
966 value &= 0xFFFFFFEF;
967 outl(value, pr->throttling.address);
968 }
969
970 /*
971 * Write the new duty_value and then enable throttling. Note
972 * that a state value of 0 leaves throttling disabled.
973 */
974 if (state) {
975 value &= duty_mask;
976 value |= duty_value;
977 outl(value, pr->throttling.address);
978
979 value |= 0x00000010;
980 outl(value, pr->throttling.address);
981 }
982
983 pr->throttling.state = state;
984
985 local_irq_enable();
986
987 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
988 "Throttling state set to T%d (%d%%)\n", state,
989 (pr->throttling.states[state].performance ? pr->
990 throttling.states[state].performance / 10 : 0)));
991
992 return 0;
993 }
994
995 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
996 int state, bool force)
997 {
998 int ret;
999 u64 value;
1000
1001 if (!pr)
1002 return -EINVAL;
1003
1004 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1005 return -EINVAL;
1006
1007 if (!pr->flags.throttling)
1008 return -ENODEV;
1009
1010 if (!force && (state == pr->throttling.state))
1011 return 0;
1012
1013 if (state < pr->throttling_platform_limit)
1014 return -EPERM;
1015
1016 value = 0;
1017 ret = acpi_get_throttling_value(pr, state, &value);
1018 if (ret >= 0) {
1019 acpi_write_throttling_state(pr, value);
1020 pr->throttling.state = state;
1021 }
1022
1023 return 0;
1024 }
1025
1026 int acpi_processor_set_throttling(struct acpi_processor *pr,
1027 int state, bool force)
1028 {
1029 cpumask_var_t saved_mask;
1030 int ret = 0;
1031 unsigned int i;
1032 struct acpi_processor *match_pr;
1033 struct acpi_processor_throttling *p_throttling;
1034 struct throttling_tstate t_state;
1035 cpumask_var_t online_throttling_cpus;
1036
1037 if (!pr)
1038 return -EINVAL;
1039
1040 if (!pr->flags.throttling)
1041 return -ENODEV;
1042
1043 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1044 return -EINVAL;
1045
1046 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1047 return -ENOMEM;
1048
1049 if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1050 free_cpumask_var(saved_mask);
1051 return -ENOMEM;
1052 }
1053
1054 cpumask_copy(saved_mask, &current->cpus_allowed);
1055 t_state.target_state = state;
1056 p_throttling = &(pr->throttling);
1057 cpumask_and(online_throttling_cpus, cpu_online_mask,
1058 p_throttling->shared_cpu_map);
1059 /*
1060 * The throttling notifier will be called for every
1061 * affected cpu in order to get one proper T-state.
1062 * The notifier event is THROTTLING_PRECHANGE.
1063 */
1064 for_each_cpu(i, online_throttling_cpus) {
1065 t_state.cpu = i;
1066 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1067 &t_state);
1068 }
1069 /*
1070 * The function of acpi_processor_set_throttling will be called
1071 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1072 * it is necessary to call it for every affected cpu. Otherwise
1073 * it can be called only for the cpu pointed by pr.
1074 */
1075 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1076 /* FIXME: use work_on_cpu() */
1077 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
1078 ret = p_throttling->acpi_processor_set_throttling(pr,
1079 t_state.target_state, force);
1080 } else {
1081 /*
1082 * When the T-state coordination is SW_ALL or HW_ALL,
1083 * it is necessary to set T-state for every affected
1084 * cpus.
1085 */
1086 for_each_cpu(i, online_throttling_cpus) {
1087 match_pr = per_cpu(processors, i);
1088 /*
1089 * If the pointer is invalid, we will report the
1090 * error message and continue.
1091 */
1092 if (!match_pr) {
1093 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1094 "Invalid Pointer for CPU %d\n", i));
1095 continue;
1096 }
1097 /*
1098 * If the throttling control is unsupported on CPU i,
1099 * we will report the error message and continue.
1100 */
1101 if (!match_pr->flags.throttling) {
1102 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1103 "Throttling Controll is unsupported "
1104 "on CPU %d\n", i));
1105 continue;
1106 }
1107 t_state.cpu = i;
1108 /* FIXME: use work_on_cpu() */
1109 set_cpus_allowed_ptr(current, cpumask_of(i));
1110 ret = match_pr->throttling.
1111 acpi_processor_set_throttling(
1112 match_pr, t_state.target_state, force);
1113 }
1114 }
1115 /*
1116 * After the set_throttling is called, the
1117 * throttling notifier is called for every
1118 * affected cpu to update the T-states.
1119 * The notifier event is THROTTLING_POSTCHANGE
1120 */
1121 for_each_cpu(i, online_throttling_cpus) {
1122 t_state.cpu = i;
1123 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1124 &t_state);
1125 }
1126 /* restore the previous state */
1127 /* FIXME: use work_on_cpu() */
1128 set_cpus_allowed_ptr(current, saved_mask);
1129 free_cpumask_var(online_throttling_cpus);
1130 free_cpumask_var(saved_mask);
1131 return ret;
1132 }
1133
1134 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1135 {
1136 int result = 0;
1137 struct acpi_processor_throttling *pthrottling;
1138
1139 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1140 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1141 pr->throttling.address,
1142 pr->throttling.duty_offset,
1143 pr->throttling.duty_width));
1144
1145 /*
1146 * Evaluate _PTC, _TSS and _TPC
1147 * They must all be present or none of them can be used.
1148 */
1149 if (acpi_processor_get_throttling_control(pr) ||
1150 acpi_processor_get_throttling_states(pr) ||
1151 acpi_processor_get_platform_limit(pr))
1152 {
1153 pr->throttling.acpi_processor_get_throttling =
1154 &acpi_processor_get_throttling_fadt;
1155 pr->throttling.acpi_processor_set_throttling =
1156 &acpi_processor_set_throttling_fadt;
1157 if (acpi_processor_get_fadt_info(pr))
1158 return 0;
1159 } else {
1160 pr->throttling.acpi_processor_get_throttling =
1161 &acpi_processor_get_throttling_ptc;
1162 pr->throttling.acpi_processor_set_throttling =
1163 &acpi_processor_set_throttling_ptc;
1164 }
1165
1166 /*
1167 * If TSD package for one CPU can't be parsed successfully, it means
1168 * that this CPU will have no coordination with other CPUs.
1169 */
1170 if (acpi_processor_get_tsd(pr)) {
1171 pthrottling = &pr->throttling;
1172 pthrottling->tsd_valid_flag = 0;
1173 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1174 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1175 }
1176
1177 /*
1178 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1179 * This shouldn't be an issue as few (if any) mobile systems ever
1180 * used this part.
1181 */
1182 if (errata.piix4.throttle) {
1183 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1184 "Throttling not supported on PIIX4 A- or B-step\n"));
1185 return 0;
1186 }
1187
1188 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1189 pr->throttling.state_count));
1190
1191 pr->flags.throttling = 1;
1192
1193 /*
1194 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1195 * thermal) decide to lower performance if it so chooses, but for now
1196 * we'll crank up the speed.
1197 */
1198
1199 result = acpi_processor_get_throttling(pr);
1200 if (result)
1201 goto end;
1202
1203 if (pr->throttling.state) {
1204 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1205 "Disabling throttling (was T%d)\n",
1206 pr->throttling.state));
1207 result = acpi_processor_set_throttling(pr, 0, false);
1208 if (result)
1209 goto end;
1210 }
1211
1212 end:
1213 if (result)
1214 pr->flags.throttling = 0;
1215
1216 return result;
1217 }
1218
1219 #ifdef CONFIG_ACPI_PROCFS
1220 /* proc interface */
1221 static int acpi_processor_throttling_seq_show(struct seq_file *seq,
1222 void *offset)
1223 {
1224 struct acpi_processor *pr = seq->private;
1225 int i = 0;
1226 int result = 0;
1227
1228 if (!pr)
1229 goto end;
1230
1231 if (!(pr->throttling.state_count > 0)) {
1232 seq_puts(seq, "<not supported>\n");
1233 goto end;
1234 }
1235
1236 result = acpi_processor_get_throttling(pr);
1237
1238 if (result) {
1239 seq_puts(seq,
1240 "Could not determine current throttling state.\n");
1241 goto end;
1242 }
1243
1244 seq_printf(seq, "state count: %d\n"
1245 "active state: T%d\n"
1246 "state available: T%d to T%d\n",
1247 pr->throttling.state_count, pr->throttling.state,
1248 pr->throttling_platform_limit,
1249 pr->throttling.state_count - 1);
1250
1251 seq_puts(seq, "states:\n");
1252 if (pr->throttling.acpi_processor_get_throttling ==
1253 acpi_processor_get_throttling_fadt) {
1254 for (i = 0; i < pr->throttling.state_count; i++)
1255 seq_printf(seq, " %cT%d: %02d%%\n",
1256 (i == pr->throttling.state ? '*' : ' '), i,
1257 (pr->throttling.states[i].performance ? pr->
1258 throttling.states[i].performance / 10 : 0));
1259 } else {
1260 for (i = 0; i < pr->throttling.state_count; i++)
1261 seq_printf(seq, " %cT%d: %02d%%\n",
1262 (i == pr->throttling.state ? '*' : ' '), i,
1263 (int)pr->throttling.states_tss[i].
1264 freqpercentage);
1265 }
1266
1267 end:
1268 return 0;
1269 }
1270
1271 static int acpi_processor_throttling_open_fs(struct inode *inode,
1272 struct file *file)
1273 {
1274 return single_open(file, acpi_processor_throttling_seq_show,
1275 PDE(inode)->data);
1276 }
1277
1278 static ssize_t acpi_processor_write_throttling(struct file *file,
1279 const char __user * buffer,
1280 size_t count, loff_t * data)
1281 {
1282 int result = 0;
1283 struct seq_file *m = file->private_data;
1284 struct acpi_processor *pr = m->private;
1285 char state_string[5] = "";
1286 char *charp = NULL;
1287 size_t state_val = 0;
1288 char tmpbuf[5] = "";
1289
1290 if (!pr || (count > sizeof(state_string) - 1))
1291 return -EINVAL;
1292
1293 if (copy_from_user(state_string, buffer, count))
1294 return -EFAULT;
1295
1296 state_string[count] = '\0';
1297 if ((count > 0) && (state_string[count-1] == '\n'))
1298 state_string[count-1] = '\0';
1299
1300 charp = state_string;
1301 if ((state_string[0] == 't') || (state_string[0] == 'T'))
1302 charp++;
1303
1304 state_val = simple_strtoul(charp, NULL, 0);
1305 if (state_val >= pr->throttling.state_count)
1306 return -EINVAL;
1307
1308 snprintf(tmpbuf, 5, "%zu", state_val);
1309
1310 if (strcmp(tmpbuf, charp) != 0)
1311 return -EINVAL;
1312
1313 result = acpi_processor_set_throttling(pr, state_val, false);
1314 if (result)
1315 return result;
1316
1317 return count;
1318 }
1319
1320 const struct file_operations acpi_processor_throttling_fops = {
1321 .owner = THIS_MODULE,
1322 .open = acpi_processor_throttling_open_fs,
1323 .read = seq_read,
1324 .write = acpi_processor_write_throttling,
1325 .llseek = seq_lseek,
1326 .release = single_release,
1327 };
1328 #endif
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree