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USB: fix the clear_tt_buffer interface
[linux-2.6/mini2440.git] / drivers / acpi / processor_throttling.c
blob227543789ba91db984862f52040fc18d1a7758e9
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 ACPI_PROCESSOR_CLASS "processor"
45 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
46 ACPI_MODULE_NAME("processor_throttling");
47
48 /* ignore_tpc:
49 * 0 -> acpi processor driver doesn't ignore _TPC values
50 * 1 -> acpi processor driver ignores _TPC values
51 */
52 static int ignore_tpc;
53 module_param(ignore_tpc, int, 0644);
54 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
55
56 struct throttling_tstate {
57 unsigned int cpu; /* cpu nr */
58 int target_state; /* target T-state */
59 };
60
61 #define THROTTLING_PRECHANGE (1)
62 #define THROTTLING_POSTCHANGE (2)
63
64 static int acpi_processor_get_throttling(struct acpi_processor *pr);
65 int acpi_processor_set_throttling(struct acpi_processor *pr, int state);
66
67 static int acpi_processor_update_tsd_coord(void)
68 {
69 int count, count_target;
70 int retval = 0;
71 unsigned int i, j;
72 cpumask_var_t covered_cpus;
73 struct acpi_processor *pr, *match_pr;
74 struct acpi_tsd_package *pdomain, *match_pdomain;
75 struct acpi_processor_throttling *pthrottling, *match_pthrottling;
76
77 if (!alloc_cpumask_var(&covered_cpus, GFP_KERNEL))
78 return -ENOMEM;
79
80 /*
81 * Now that we have _TSD data from all CPUs, lets setup T-state
82 * coordination between all CPUs.
83 */
84 for_each_possible_cpu(i) {
85 pr = per_cpu(processors, i);
86 if (!pr)
87 continue;
88
89 /* Basic validity check for domain info */
90 pthrottling = &(pr->throttling);
91
92 /*
93 * If tsd package for one cpu is invalid, the coordination
94 * among all CPUs is thought as invalid.
95 * Maybe it is ugly.
96 */
97 if (!pthrottling->tsd_valid_flag) {
98 retval = -EINVAL;
99 break;
100 }
101 }
102 if (retval)
103 goto err_ret;
104
105 cpumask_clear(covered_cpus);
106 for_each_possible_cpu(i) {
107 pr = per_cpu(processors, i);
108 if (!pr)
109 continue;
110
111 if (cpumask_test_cpu(i, covered_cpus))
112 continue;
113 pthrottling = &pr->throttling;
114
115 pdomain = &(pthrottling->domain_info);
116 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
117 cpumask_set_cpu(i, covered_cpus);
118 /*
119 * If the number of processor in the TSD domain is 1, it is
120 * unnecessary to parse the coordination for this CPU.
121 */
122 if (pdomain->num_processors <= 1)
123 continue;
124
125 /* Validate the Domain info */
126 count_target = pdomain->num_processors;
127 count = 1;
128
129 for_each_possible_cpu(j) {
130 if (i == j)
131 continue;
132
133 match_pr = per_cpu(processors, j);
134 if (!match_pr)
135 continue;
136
137 match_pthrottling = &(match_pr->throttling);
138 match_pdomain = &(match_pthrottling->domain_info);
139 if (match_pdomain->domain != pdomain->domain)
140 continue;
141
142 /* Here i and j are in the same domain.
143 * If two TSD packages have the same domain, they
144 * should have the same num_porcessors and
145 * coordination type. Otherwise it will be regarded
146 * as illegal.
147 */
148 if (match_pdomain->num_processors != count_target) {
149 retval = -EINVAL;
150 goto err_ret;
151 }
152
153 if (pdomain->coord_type != match_pdomain->coord_type) {
154 retval = -EINVAL;
155 goto err_ret;
156 }
157
158 cpumask_set_cpu(j, covered_cpus);
159 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
160 count++;
161 }
162 for_each_possible_cpu(j) {
163 if (i == j)
164 continue;
165
166 match_pr = per_cpu(processors, j);
167 if (!match_pr)
168 continue;
169
170 match_pthrottling = &(match_pr->throttling);
171 match_pdomain = &(match_pthrottling->domain_info);
172 if (match_pdomain->domain != pdomain->domain)
173 continue;
174
175 /*
176 * If some CPUS have the same domain, they
177 * will have the same shared_cpu_map.
178 */
179 cpumask_copy(match_pthrottling->shared_cpu_map,
180 pthrottling->shared_cpu_map);
181 }
182 }
183
184 err_ret:
185 free_cpumask_var(covered_cpus);
186
187 for_each_possible_cpu(i) {
188 pr = per_cpu(processors, i);
189 if (!pr)
190 continue;
191
192 /*
193 * Assume no coordination on any error parsing domain info.
194 * The coordination type will be forced as SW_ALL.
195 */
196 if (retval) {
197 pthrottling = &(pr->throttling);
198 cpumask_clear(pthrottling->shared_cpu_map);
199 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
200 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
201 }
202 }
203
204 return retval;
205 }
206
207 /*
208 * Update the T-state coordination after the _TSD
209 * data for all cpus is obtained.
210 */
211 void acpi_processor_throttling_init(void)
212 {
213 if (acpi_processor_update_tsd_coord())
214 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
215 "Assume no T-state coordination\n"));
216
217 return;
218 }
219
220 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
221 {
222 struct throttling_tstate *p_tstate = data;
223 struct acpi_processor *pr;
224 unsigned int cpu ;
225 int target_state;
226 struct acpi_processor_limit *p_limit;
227 struct acpi_processor_throttling *p_throttling;
228
229 cpu = p_tstate->cpu;
230 pr = per_cpu(processors, cpu);
231 if (!pr) {
232 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
233 return 0;
234 }
235 if (!pr->flags.throttling) {
236 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
237 "unsupported on CPU %d\n", cpu));
238 return 0;
239 }
240 target_state = p_tstate->target_state;
241 p_throttling = &(pr->throttling);
242 switch (event) {
243 case THROTTLING_PRECHANGE:
244 /*
245 * Prechange event is used to choose one proper t-state,
246 * which meets the limits of thermal, user and _TPC.
247 */
248 p_limit = &pr->limit;
249 if (p_limit->thermal.tx > target_state)
250 target_state = p_limit->thermal.tx;
251 if (p_limit->user.tx > target_state)
252 target_state = p_limit->user.tx;
253 if (pr->throttling_platform_limit > target_state)
254 target_state = pr->throttling_platform_limit;
255 if (target_state >= p_throttling->state_count) {
256 printk(KERN_WARNING
257 "Exceed the limit of T-state \n");
258 target_state = p_throttling->state_count - 1;
259 }
260 p_tstate->target_state = target_state;
261 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
262 "target T-state of CPU %d is T%d\n",
263 cpu, target_state));
264 break;
265 case THROTTLING_POSTCHANGE:
266 /*
267 * Postchange event is only used to update the
268 * T-state flag of acpi_processor_throttling.
269 */
270 p_throttling->state = target_state;
271 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
272 "CPU %d is switched to T%d\n",
273 cpu, target_state));
274 break;
275 default:
276 printk(KERN_WARNING
277 "Unsupported Throttling notifier event\n");
278 break;
279 }
280
281 return 0;
282 }
283
284 /*
285 * _TPC - Throttling Present Capabilities
286 */
287 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
288 {
289 acpi_status status = 0;
290 unsigned long long tpc = 0;
291
292 if (!pr)
293 return -EINVAL;
294
295 if (ignore_tpc)
296 goto end;
297
298 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
299 if (ACPI_FAILURE(status)) {
300 if (status != AE_NOT_FOUND) {
301 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
302 }
303 return -ENODEV;
304 }
305
306 end:
307 pr->throttling_platform_limit = (int)tpc;
308 return 0;
309 }
310
311 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
312 {
313 int result = 0;
314 int throttling_limit;
315 int current_state;
316 struct acpi_processor_limit *limit;
317 int target_state;
318
319 if (ignore_tpc)
320 return 0;
321
322 result = acpi_processor_get_platform_limit(pr);
323 if (result) {
324 /* Throttling Limit is unsupported */
325 return result;
326 }
327
328 throttling_limit = pr->throttling_platform_limit;
329 if (throttling_limit >= pr->throttling.state_count) {
330 /* Uncorrect Throttling Limit */
331 return -EINVAL;
332 }
333
334 current_state = pr->throttling.state;
335 if (current_state > throttling_limit) {
336 /*
337 * The current state can meet the requirement of
338 * _TPC limit. But it is reasonable that OSPM changes
339 * t-states from high to low for better performance.
340 * Of course the limit condition of thermal
341 * and user should be considered.
342 */
343 limit = &pr->limit;
344 target_state = throttling_limit;
345 if (limit->thermal.tx > target_state)
346 target_state = limit->thermal.tx;
347 if (limit->user.tx > target_state)
348 target_state = limit->user.tx;
349 } else if (current_state == throttling_limit) {
350 /*
351 * Unnecessary to change the throttling state
352 */
353 return 0;
354 } else {
355 /*
356 * If the current state is lower than the limit of _TPC, it
357 * will be forced to switch to the throttling state defined
358 * by throttling_platfor_limit.
359 * Because the previous state meets with the limit condition
360 * of thermal and user, it is unnecessary to check it again.
361 */
362 target_state = throttling_limit;
363 }
364 return acpi_processor_set_throttling(pr, target_state);
365 }
366
367 /*
368 * _PTC - Processor Throttling Control (and status) register location
369 */
370 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
371 {
372 int result = 0;
373 acpi_status status = 0;
374 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
375 union acpi_object *ptc = NULL;
376 union acpi_object obj = { 0 };
377 struct acpi_processor_throttling *throttling;
378
379 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
380 if (ACPI_FAILURE(status)) {
381 if (status != AE_NOT_FOUND) {
382 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
383 }
384 return -ENODEV;
385 }
386
387 ptc = (union acpi_object *)buffer.pointer;
388 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
389 || (ptc->package.count != 2)) {
390 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
391 result = -EFAULT;
392 goto end;
393 }
394
395 /*
396 * control_register
397 */
398
399 obj = ptc->package.elements[0];
400
401 if ((obj.type != ACPI_TYPE_BUFFER)
402 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
403 || (obj.buffer.pointer == NULL)) {
404 printk(KERN_ERR PREFIX
405 "Invalid _PTC data (control_register)\n");
406 result = -EFAULT;
407 goto end;
408 }
409 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
410 sizeof(struct acpi_ptc_register));
411
412 /*
413 * status_register
414 */
415
416 obj = ptc->package.elements[1];
417
418 if ((obj.type != ACPI_TYPE_BUFFER)
419 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
420 || (obj.buffer.pointer == NULL)) {
421 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
422 result = -EFAULT;
423 goto end;
424 }
425
426 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
427 sizeof(struct acpi_ptc_register));
428
429 throttling = &pr->throttling;
430
431 if ((throttling->control_register.bit_width +
432 throttling->control_register.bit_offset) > 32) {
433 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
434 result = -EFAULT;
435 goto end;
436 }
437
438 if ((throttling->status_register.bit_width +
439 throttling->status_register.bit_offset) > 32) {
440 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
441 result = -EFAULT;
442 goto end;
443 }
444
445 end:
446 kfree(buffer.pointer);
447
448 return result;
449 }
450
451 /*
452 * _TSS - Throttling Supported States
453 */
454 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
455 {
456 int result = 0;
457 acpi_status status = AE_OK;
458 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
459 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
460 struct acpi_buffer state = { 0, NULL };
461 union acpi_object *tss = NULL;
462 int i;
463
464 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
465 if (ACPI_FAILURE(status)) {
466 if (status != AE_NOT_FOUND) {
467 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
468 }
469 return -ENODEV;
470 }
471
472 tss = buffer.pointer;
473 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
474 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
475 result = -EFAULT;
476 goto end;
477 }
478
479 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
480 tss->package.count));
481
482 pr->throttling.state_count = tss->package.count;
483 pr->throttling.states_tss =
484 kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
485 GFP_KERNEL);
486 if (!pr->throttling.states_tss) {
487 result = -ENOMEM;
488 goto end;
489 }
490
491 for (i = 0; i < pr->throttling.state_count; i++) {
492
493 struct acpi_processor_tx_tss *tx =
494 (struct acpi_processor_tx_tss *)&(pr->throttling.
495 states_tss[i]);
496
497 state.length = sizeof(struct acpi_processor_tx_tss);
498 state.pointer = tx;
499
500 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
501
502 status = acpi_extract_package(&(tss->package.elements[i]),
503 &format, &state);
504 if (ACPI_FAILURE(status)) {
505 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
506 result = -EFAULT;
507 kfree(pr->throttling.states_tss);
508 goto end;
509 }
510
511 if (!tx->freqpercentage) {
512 printk(KERN_ERR PREFIX
513 "Invalid _TSS data: freq is zero\n");
514 result = -EFAULT;
515 kfree(pr->throttling.states_tss);
516 goto end;
517 }
518 }
519
520 end:
521 kfree(buffer.pointer);
522
523 return result;
524 }
525
526 /*
527 * _TSD - T-State Dependencies
528 */
529 static int acpi_processor_get_tsd(struct acpi_processor *pr)
530 {
531 int result = 0;
532 acpi_status status = AE_OK;
533 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
534 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
535 struct acpi_buffer state = { 0, NULL };
536 union acpi_object *tsd = NULL;
537 struct acpi_tsd_package *pdomain;
538 struct acpi_processor_throttling *pthrottling;
539
540 pthrottling = &pr->throttling;
541 pthrottling->tsd_valid_flag = 0;
542
543 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
544 if (ACPI_FAILURE(status)) {
545 if (status != AE_NOT_FOUND) {
546 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
547 }
548 return -ENODEV;
549 }
550
551 tsd = buffer.pointer;
552 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
553 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
554 result = -EFAULT;
555 goto end;
556 }
557
558 if (tsd->package.count != 1) {
559 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
560 result = -EFAULT;
561 goto end;
562 }
563
564 pdomain = &(pr->throttling.domain_info);
565
566 state.length = sizeof(struct acpi_tsd_package);
567 state.pointer = pdomain;
568
569 status = acpi_extract_package(&(tsd->package.elements[0]),
570 &format, &state);
571 if (ACPI_FAILURE(status)) {
572 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
573 result = -EFAULT;
574 goto end;
575 }
576
577 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
578 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
579 result = -EFAULT;
580 goto end;
581 }
582
583 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
584 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
585 result = -EFAULT;
586 goto end;
587 }
588
589 pthrottling = &pr->throttling;
590 pthrottling->tsd_valid_flag = 1;
591 pthrottling->shared_type = pdomain->coord_type;
592 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
593 /*
594 * If the coordination type is not defined in ACPI spec,
595 * the tsd_valid_flag will be clear and coordination type
596 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
597 */
598 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
599 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
600 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
601 pthrottling->tsd_valid_flag = 0;
602 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
603 }
604
605 end:
606 kfree(buffer.pointer);
607 return result;
608 }
609
610 /* --------------------------------------------------------------------------
611 Throttling Control
612 -------------------------------------------------------------------------- */
613 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
614 {
615 int state = 0;
616 u32 value = 0;
617 u32 duty_mask = 0;
618 u32 duty_value = 0;
619
620 if (!pr)
621 return -EINVAL;
622
623 if (!pr->flags.throttling)
624 return -ENODEV;
625
626 pr->throttling.state = 0;
627
628 duty_mask = pr->throttling.state_count - 1;
629
630 duty_mask <<= pr->throttling.duty_offset;
631
632 local_irq_disable();
633
634 value = inl(pr->throttling.address);
635
636 /*
637 * Compute the current throttling state when throttling is enabled
638 * (bit 4 is on).
639 */
640 if (value & 0x10) {
641 duty_value = value & duty_mask;
642 duty_value >>= pr->throttling.duty_offset;
643
644 if (duty_value)
645 state = pr->throttling.state_count - duty_value;
646 }
647
648 pr->throttling.state = state;
649
650 local_irq_enable();
651
652 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
653 "Throttling state is T%d (%d%% throttling applied)\n",
654 state, pr->throttling.states[state].performance));
655
656 return 0;
657 }
658
659 #ifdef CONFIG_X86
660 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
661 acpi_integer * value)
662 {
663 struct cpuinfo_x86 *c;
664 u64 msr_high, msr_low;
665 unsigned int cpu;
666 u64 msr = 0;
667 int ret = -1;
668
669 cpu = pr->id;
670 c = &cpu_data(cpu);
671
672 if ((c->x86_vendor != X86_VENDOR_INTEL) ||
673 !cpu_has(c, X86_FEATURE_ACPI)) {
674 printk(KERN_ERR PREFIX
675 "HARDWARE addr space,NOT supported yet\n");
676 } else {
677 msr_low = 0;
678 msr_high = 0;
679 rdmsr_safe(MSR_IA32_THERM_CONTROL,
680 (u32 *)&msr_low , (u32 *) &msr_high);
681 msr = (msr_high << 32) | msr_low;
682 *value = (acpi_integer) msr;
683 ret = 0;
684 }
685 return ret;
686 }
687
688 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
689 {
690 struct cpuinfo_x86 *c;
691 unsigned int cpu;
692 int ret = -1;
693 u64 msr;
694
695 cpu = pr->id;
696 c = &cpu_data(cpu);
697
698 if ((c->x86_vendor != X86_VENDOR_INTEL) ||
699 !cpu_has(c, X86_FEATURE_ACPI)) {
700 printk(KERN_ERR PREFIX
701 "HARDWARE addr space,NOT supported yet\n");
702 } else {
703 msr = value;
704 wrmsr_safe(MSR_IA32_THERM_CONTROL,
705 msr & 0xffffffff, msr >> 32);
706 ret = 0;
707 }
708 return ret;
709 }
710 #else
711 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
712 acpi_integer * value)
713 {
714 printk(KERN_ERR PREFIX
715 "HARDWARE addr space,NOT supported yet\n");
716 return -1;
717 }
718
719 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
720 {
721 printk(KERN_ERR PREFIX
722 "HARDWARE addr space,NOT supported yet\n");
723 return -1;
724 }
725 #endif
726
727 static int acpi_read_throttling_status(struct acpi_processor *pr,
728 acpi_integer *value)
729 {
730 u32 bit_width, bit_offset;
731 u64 ptc_value;
732 u64 ptc_mask;
733 struct acpi_processor_throttling *throttling;
734 int ret = -1;
735
736 throttling = &pr->throttling;
737 switch (throttling->status_register.space_id) {
738 case ACPI_ADR_SPACE_SYSTEM_IO:
739 ptc_value = 0;
740 bit_width = throttling->status_register.bit_width;
741 bit_offset = throttling->status_register.bit_offset;
742
743 acpi_os_read_port((acpi_io_address) throttling->status_register.
744 address, (u32 *) &ptc_value,
745 (u32) (bit_width + bit_offset));
746 ptc_mask = (1 << bit_width) - 1;
747 *value = (acpi_integer) ((ptc_value >> bit_offset) & ptc_mask);
748 ret = 0;
749 break;
750 case ACPI_ADR_SPACE_FIXED_HARDWARE:
751 ret = acpi_throttling_rdmsr(pr, value);
752 break;
753 default:
754 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
755 (u32) (throttling->status_register.space_id));
756 }
757 return ret;
758 }
759
760 static int acpi_write_throttling_state(struct acpi_processor *pr,
761 acpi_integer value)
762 {
763 u32 bit_width, bit_offset;
764 u64 ptc_value;
765 u64 ptc_mask;
766 struct acpi_processor_throttling *throttling;
767 int ret = -1;
768
769 throttling = &pr->throttling;
770 switch (throttling->control_register.space_id) {
771 case ACPI_ADR_SPACE_SYSTEM_IO:
772 bit_width = throttling->control_register.bit_width;
773 bit_offset = throttling->control_register.bit_offset;
774 ptc_mask = (1 << bit_width) - 1;
775 ptc_value = value & ptc_mask;
776
777 acpi_os_write_port((acpi_io_address) throttling->
778 control_register.address,
779 (u32) (ptc_value << bit_offset),
780 (u32) (bit_width + bit_offset));
781 ret = 0;
782 break;
783 case ACPI_ADR_SPACE_FIXED_HARDWARE:
784 ret = acpi_throttling_wrmsr(pr, value);
785 break;
786 default:
787 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
788 (u32) (throttling->control_register.space_id));
789 }
790 return ret;
791 }
792
793 static int acpi_get_throttling_state(struct acpi_processor *pr,
794 acpi_integer value)
795 {
796 int i;
797
798 for (i = 0; i < pr->throttling.state_count; i++) {
799 struct acpi_processor_tx_tss *tx =
800 (struct acpi_processor_tx_tss *)&(pr->throttling.
801 states_tss[i]);
802 if (tx->control == value)
803 return i;
804 }
805 return -1;
806 }
807
808 static int acpi_get_throttling_value(struct acpi_processor *pr,
809 int state, acpi_integer *value)
810 {
811 int ret = -1;
812
813 if (state >= 0 && state <= pr->throttling.state_count) {
814 struct acpi_processor_tx_tss *tx =
815 (struct acpi_processor_tx_tss *)&(pr->throttling.
816 states_tss[state]);
817 *value = tx->control;
818 ret = 0;
819 }
820 return ret;
821 }
822
823 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
824 {
825 int state = 0;
826 int ret;
827 acpi_integer value;
828
829 if (!pr)
830 return -EINVAL;
831
832 if (!pr->flags.throttling)
833 return -ENODEV;
834
835 pr->throttling.state = 0;
836
837 value = 0;
838 ret = acpi_read_throttling_status(pr, &value);
839 if (ret >= 0) {
840 state = acpi_get_throttling_state(pr, value);
841 if (state == -1) {
842 ACPI_WARNING((AE_INFO,
843 "Invalid throttling state, reset"));
844 state = 0;
845 ret = acpi_processor_set_throttling(pr, state);
846 if (ret)
847 return ret;
848 }
849 pr->throttling.state = state;
850 }
851
852 return 0;
853 }
854
855 static int acpi_processor_get_throttling(struct acpi_processor *pr)
856 {
857 cpumask_var_t saved_mask;
858 int ret;
859
860 if (!pr)
861 return -EINVAL;
862
863 if (!pr->flags.throttling)
864 return -ENODEV;
865
866 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
867 return -ENOMEM;
868
869 /*
870 * Migrate task to the cpu pointed by pr.
871 */
872 cpumask_copy(saved_mask, &current->cpus_allowed);
873 /* FIXME: use work_on_cpu() */
874 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
875 ret = pr->throttling.acpi_processor_get_throttling(pr);
876 /* restore the previous state */
877 set_cpus_allowed_ptr(current, saved_mask);
878 free_cpumask_var(saved_mask);
879
880 return ret;
881 }
882
883 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
884 {
885 int i, step;
886
887 if (!pr->throttling.address) {
888 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
889 return -EINVAL;
890 } else if (!pr->throttling.duty_width) {
891 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
892 return -EINVAL;
893 }
894 /* TBD: Support duty_cycle values that span bit 4. */
895 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
896 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
897 return -EINVAL;
898 }
899
900 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
901
902 /*
903 * Compute state values. Note that throttling displays a linear power
904 * performance relationship (at 50% performance the CPU will consume
905 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
906 */
907
908 step = (1000 / pr->throttling.state_count);
909
910 for (i = 0; i < pr->throttling.state_count; i++) {
911 pr->throttling.states[i].performance = 1000 - step * i;
912 pr->throttling.states[i].power = 1000 - step * i;
913 }
914 return 0;
915 }
916
917 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
918 int state)
919 {
920 u32 value = 0;
921 u32 duty_mask = 0;
922 u32 duty_value = 0;
923
924 if (!pr)
925 return -EINVAL;
926
927 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
928 return -EINVAL;
929
930 if (!pr->flags.throttling)
931 return -ENODEV;
932
933 if (state == pr->throttling.state)
934 return 0;
935
936 if (state < pr->throttling_platform_limit)
937 return -EPERM;
938 /*
939 * Calculate the duty_value and duty_mask.
940 */
941 if (state) {
942 duty_value = pr->throttling.state_count - state;
943
944 duty_value <<= pr->throttling.duty_offset;
945
946 /* Used to clear all duty_value bits */
947 duty_mask = pr->throttling.state_count - 1;
948
949 duty_mask <<= acpi_gbl_FADT.duty_offset;
950 duty_mask = ~duty_mask;
951 }
952
953 local_irq_disable();
954
955 /*
956 * Disable throttling by writing a 0 to bit 4. Note that we must
957 * turn it off before you can change the duty_value.
958 */
959 value = inl(pr->throttling.address);
960 if (value & 0x10) {
961 value &= 0xFFFFFFEF;
962 outl(value, pr->throttling.address);
963 }
964
965 /*
966 * Write the new duty_value and then enable throttling. Note
967 * that a state value of 0 leaves throttling disabled.
968 */
969 if (state) {
970 value &= duty_mask;
971 value |= duty_value;
972 outl(value, pr->throttling.address);
973
974 value |= 0x00000010;
975 outl(value, pr->throttling.address);
976 }
977
978 pr->throttling.state = state;
979
980 local_irq_enable();
981
982 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
983 "Throttling state set to T%d (%d%%)\n", state,
984 (pr->throttling.states[state].performance ? pr->
985 throttling.states[state].performance / 10 : 0)));
986
987 return 0;
988 }
989
990 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
991 int state)
992 {
993 int ret;
994 acpi_integer value;
995
996 if (!pr)
997 return -EINVAL;
998
999 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1000 return -EINVAL;
1001
1002 if (!pr->flags.throttling)
1003 return -ENODEV;
1004
1005 if (state == pr->throttling.state)
1006 return 0;
1007
1008 if (state < pr->throttling_platform_limit)
1009 return -EPERM;
1010
1011 value = 0;
1012 ret = acpi_get_throttling_value(pr, state, &value);
1013 if (ret >= 0) {
1014 acpi_write_throttling_state(pr, value);
1015 pr->throttling.state = state;
1016 }
1017
1018 return 0;
1019 }
1020
1021 int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
1022 {
1023 cpumask_var_t saved_mask;
1024 int ret = 0;
1025 unsigned int i;
1026 struct acpi_processor *match_pr;
1027 struct acpi_processor_throttling *p_throttling;
1028 struct throttling_tstate t_state;
1029 cpumask_var_t online_throttling_cpus;
1030
1031 if (!pr)
1032 return -EINVAL;
1033
1034 if (!pr->flags.throttling)
1035 return -ENODEV;
1036
1037 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1038 return -EINVAL;
1039
1040 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1041 return -ENOMEM;
1042
1043 if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1044 free_cpumask_var(saved_mask);
1045 return -ENOMEM;
1046 }
1047
1048 cpumask_copy(saved_mask, &current->cpus_allowed);
1049 t_state.target_state = state;
1050 p_throttling = &(pr->throttling);
1051 cpumask_and(online_throttling_cpus, cpu_online_mask,
1052 p_throttling->shared_cpu_map);
1053 /*
1054 * The throttling notifier will be called for every
1055 * affected cpu in order to get one proper T-state.
1056 * The notifier event is THROTTLING_PRECHANGE.
1057 */
1058 for_each_cpu(i, online_throttling_cpus) {
1059 t_state.cpu = i;
1060 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1061 &t_state);
1062 }
1063 /*
1064 * The function of acpi_processor_set_throttling will be called
1065 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1066 * it is necessary to call it for every affected cpu. Otherwise
1067 * it can be called only for the cpu pointed by pr.
1068 */
1069 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1070 /* FIXME: use work_on_cpu() */
1071 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
1072 ret = p_throttling->acpi_processor_set_throttling(pr,
1073 t_state.target_state);
1074 } else {
1075 /*
1076 * When the T-state coordination is SW_ALL or HW_ALL,
1077 * it is necessary to set T-state for every affected
1078 * cpus.
1079 */
1080 for_each_cpu(i, online_throttling_cpus) {
1081 match_pr = per_cpu(processors, i);
1082 /*
1083 * If the pointer is invalid, we will report the
1084 * error message and continue.
1085 */
1086 if (!match_pr) {
1087 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1088 "Invalid Pointer for CPU %d\n", i));
1089 continue;
1090 }
1091 /*
1092 * If the throttling control is unsupported on CPU i,
1093 * we will report the error message and continue.
1094 */
1095 if (!match_pr->flags.throttling) {
1096 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1097 "Throttling Controll is unsupported "
1098 "on CPU %d\n", i));
1099 continue;
1100 }
1101 t_state.cpu = i;
1102 /* FIXME: use work_on_cpu() */
1103 set_cpus_allowed_ptr(current, cpumask_of(i));
1104 ret = match_pr->throttling.
1105 acpi_processor_set_throttling(
1106 match_pr, t_state.target_state);
1107 }
1108 }
1109 /*
1110 * After the set_throttling is called, the
1111 * throttling notifier is called for every
1112 * affected cpu to update the T-states.
1113 * The notifier event is THROTTLING_POSTCHANGE
1114 */
1115 for_each_cpu(i, online_throttling_cpus) {
1116 t_state.cpu = i;
1117 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1118 &t_state);
1119 }
1120 /* restore the previous state */
1121 /* FIXME: use work_on_cpu() */
1122 set_cpus_allowed_ptr(current, saved_mask);
1123 free_cpumask_var(online_throttling_cpus);
1124 free_cpumask_var(saved_mask);
1125 return ret;
1126 }
1127
1128 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1129 {
1130 int result = 0;
1131 struct acpi_processor_throttling *pthrottling;
1132
1133 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1134 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1135 pr->throttling.address,
1136 pr->throttling.duty_offset,
1137 pr->throttling.duty_width));
1138
1139 if (!pr)
1140 return -EINVAL;
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);
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
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);
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 };
Support for the Chinese Samsung S3C2440 based development boards