ACPI processor: introduce module parameter processor.ignore_tpc
[linux-3.10.git] / drivers / acpi / processor_throttling.c
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                 pr->throttling.state = state;
842         }
843
844         return 0;
845 }
846
847 static int acpi_processor_get_throttling(struct acpi_processor *pr)
848 {
849         cpumask_var_t saved_mask;
850         int ret;
851
852         if (!pr)
853                 return -EINVAL;
854
855         if (!pr->flags.throttling)
856                 return -ENODEV;
857
858         if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
859                 return -ENOMEM;
860
861         /*
862          * Migrate task to the cpu pointed by pr.
863          */
864         cpumask_copy(saved_mask, &current->cpus_allowed);
865         /* FIXME: use work_on_cpu() */
866         set_cpus_allowed_ptr(current, cpumask_of(pr->id));
867         ret = pr->throttling.acpi_processor_get_throttling(pr);
868         /* restore the previous state */
869         set_cpus_allowed_ptr(current, saved_mask);
870         free_cpumask_var(saved_mask);
871
872         return ret;
873 }
874
875 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
876 {
877         int i, step;
878
879         if (!pr->throttling.address) {
880                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
881                 return -EINVAL;
882         } else if (!pr->throttling.duty_width) {
883                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
884                 return -EINVAL;
885         }
886         /* TBD: Support duty_cycle values that span bit 4. */
887         else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
888                 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
889                 return -EINVAL;
890         }
891
892         pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
893
894         /*
895          * Compute state values. Note that throttling displays a linear power
896          * performance relationship (at 50% performance the CPU will consume
897          * 50% power).  Values are in 1/10th of a percent to preserve accuracy.
898          */
899
900         step = (1000 / pr->throttling.state_count);
901
902         for (i = 0; i < pr->throttling.state_count; i++) {
903                 pr->throttling.states[i].performance = 1000 - step * i;
904                 pr->throttling.states[i].power = 1000 - step * i;
905         }
906         return 0;
907 }
908
909 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
910                                               int state)
911 {
912         u32 value = 0;
913         u32 duty_mask = 0;
914         u32 duty_value = 0;
915
916         if (!pr)
917                 return -EINVAL;
918
919         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
920                 return -EINVAL;
921
922         if (!pr->flags.throttling)
923                 return -ENODEV;
924
925         if (state == pr->throttling.state)
926                 return 0;
927
928         if (state < pr->throttling_platform_limit)
929                 return -EPERM;
930         /*
931          * Calculate the duty_value and duty_mask.
932          */
933         if (state) {
934                 duty_value = pr->throttling.state_count - state;
935
936                 duty_value <<= pr->throttling.duty_offset;
937
938                 /* Used to clear all duty_value bits */
939                 duty_mask = pr->throttling.state_count - 1;
940
941                 duty_mask <<= acpi_gbl_FADT.duty_offset;
942                 duty_mask = ~duty_mask;
943         }
944
945         local_irq_disable();
946
947         /*
948          * Disable throttling by writing a 0 to bit 4.  Note that we must
949          * turn it off before you can change the duty_value.
950          */
951         value = inl(pr->throttling.address);
952         if (value & 0x10) {
953                 value &= 0xFFFFFFEF;
954                 outl(value, pr->throttling.address);
955         }
956
957         /*
958          * Write the new duty_value and then enable throttling.  Note
959          * that a state value of 0 leaves throttling disabled.
960          */
961         if (state) {
962                 value &= duty_mask;
963                 value |= duty_value;
964                 outl(value, pr->throttling.address);
965
966                 value |= 0x00000010;
967                 outl(value, pr->throttling.address);
968         }
969
970         pr->throttling.state = state;
971
972         local_irq_enable();
973
974         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
975                           "Throttling state set to T%d (%d%%)\n", state,
976                           (pr->throttling.states[state].performance ? pr->
977                            throttling.states[state].performance / 10 : 0)));
978
979         return 0;
980 }
981
982 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
983                                              int state)
984 {
985         int ret;
986         acpi_integer value;
987
988         if (!pr)
989                 return -EINVAL;
990
991         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
992                 return -EINVAL;
993
994         if (!pr->flags.throttling)
995                 return -ENODEV;
996
997         if (state == pr->throttling.state)
998                 return 0;
999
1000         if (state < pr->throttling_platform_limit)
1001                 return -EPERM;
1002
1003         value = 0;
1004         ret = acpi_get_throttling_value(pr, state, &value);
1005         if (ret >= 0) {
1006                 acpi_write_throttling_state(pr, value);
1007                 pr->throttling.state = state;
1008         }
1009
1010         return 0;
1011 }
1012
1013 int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
1014 {
1015         cpumask_var_t saved_mask;
1016         int ret = 0;
1017         unsigned int i;
1018         struct acpi_processor *match_pr;
1019         struct acpi_processor_throttling *p_throttling;
1020         struct throttling_tstate t_state;
1021         cpumask_var_t online_throttling_cpus;
1022
1023         if (!pr)
1024                 return -EINVAL;
1025
1026         if (!pr->flags.throttling)
1027                 return -ENODEV;
1028
1029         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1030                 return -EINVAL;
1031
1032         if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1033                 return -ENOMEM;
1034
1035         if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1036                 free_cpumask_var(saved_mask);
1037                 return -ENOMEM;
1038         }
1039
1040         cpumask_copy(saved_mask, &current->cpus_allowed);
1041         t_state.target_state = state;
1042         p_throttling = &(pr->throttling);
1043         cpumask_and(online_throttling_cpus, cpu_online_mask,
1044                     p_throttling->shared_cpu_map);
1045         /*
1046          * The throttling notifier will be called for every
1047          * affected cpu in order to get one proper T-state.
1048          * The notifier event is THROTTLING_PRECHANGE.
1049          */
1050         for_each_cpu(i, online_throttling_cpus) {
1051                 t_state.cpu = i;
1052                 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1053                                                         &t_state);
1054         }
1055         /*
1056          * The function of acpi_processor_set_throttling will be called
1057          * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1058          * it is necessary to call it for every affected cpu. Otherwise
1059          * it can be called only for the cpu pointed by pr.
1060          */
1061         if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1062                 /* FIXME: use work_on_cpu() */
1063                 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
1064                 ret = p_throttling->acpi_processor_set_throttling(pr,
1065                                                 t_state.target_state);
1066         } else {
1067                 /*
1068                  * When the T-state coordination is SW_ALL or HW_ALL,
1069                  * it is necessary to set T-state for every affected
1070                  * cpus.
1071                  */
1072                 for_each_cpu(i, online_throttling_cpus) {
1073                         match_pr = per_cpu(processors, i);
1074                         /*
1075                          * If the pointer is invalid, we will report the
1076                          * error message and continue.
1077                          */
1078                         if (!match_pr) {
1079                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1080                                         "Invalid Pointer for CPU %d\n", i));
1081                                 continue;
1082                         }
1083                         /*
1084                          * If the throttling control is unsupported on CPU i,
1085                          * we will report the error message and continue.
1086                          */
1087                         if (!match_pr->flags.throttling) {
1088                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1089                                         "Throttling Controll is unsupported "
1090                                         "on CPU %d\n", i));
1091                                 continue;
1092                         }
1093                         t_state.cpu = i;
1094                         /* FIXME: use work_on_cpu() */
1095                         set_cpus_allowed_ptr(current, cpumask_of(i));
1096                         ret = match_pr->throttling.
1097                                 acpi_processor_set_throttling(
1098                                 match_pr, t_state.target_state);
1099                 }
1100         }
1101         /*
1102          * After the set_throttling is called, the
1103          * throttling notifier is called for every
1104          * affected cpu to update the T-states.
1105          * The notifier event is THROTTLING_POSTCHANGE
1106          */
1107         for_each_cpu(i, online_throttling_cpus) {
1108                 t_state.cpu = i;
1109                 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1110                                                         &t_state);
1111         }
1112         /* restore the previous state */
1113         /* FIXME: use work_on_cpu() */
1114         set_cpus_allowed_ptr(current, saved_mask);
1115         free_cpumask_var(online_throttling_cpus);
1116         free_cpumask_var(saved_mask);
1117         return ret;
1118 }
1119
1120 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1121 {
1122         int result = 0;
1123         struct acpi_processor_throttling *pthrottling;
1124
1125         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1126                           "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1127                           pr->throttling.address,
1128                           pr->throttling.duty_offset,
1129                           pr->throttling.duty_width));
1130
1131         if (!pr)
1132                 return -EINVAL;
1133
1134         /*
1135          * Evaluate _PTC, _TSS and _TPC
1136          * They must all be present or none of them can be used.
1137          */
1138         if (acpi_processor_get_throttling_control(pr) ||
1139                 acpi_processor_get_throttling_states(pr) ||
1140                 acpi_processor_get_platform_limit(pr))
1141         {
1142                 pr->throttling.acpi_processor_get_throttling =
1143                     &acpi_processor_get_throttling_fadt;
1144                 pr->throttling.acpi_processor_set_throttling =
1145                     &acpi_processor_set_throttling_fadt;
1146                 if (acpi_processor_get_fadt_info(pr))
1147                         return 0;
1148         } else {
1149                 pr->throttling.acpi_processor_get_throttling =
1150                     &acpi_processor_get_throttling_ptc;
1151                 pr->throttling.acpi_processor_set_throttling =
1152                     &acpi_processor_set_throttling_ptc;
1153         }
1154
1155         /*
1156          * If TSD package for one CPU can't be parsed successfully, it means
1157          * that this CPU will have no coordination with other CPUs.
1158          */
1159         if (acpi_processor_get_tsd(pr)) {
1160                 pthrottling = &pr->throttling;
1161                 pthrottling->tsd_valid_flag = 0;
1162                 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1163                 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1164         }
1165
1166         /*
1167          * PIIX4 Errata: We don't support throttling on the original PIIX4.
1168          * This shouldn't be an issue as few (if any) mobile systems ever
1169          * used this part.
1170          */
1171         if (errata.piix4.throttle) {
1172                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1173                                   "Throttling not supported on PIIX4 A- or B-step\n"));
1174                 return 0;
1175         }
1176
1177         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1178                           pr->throttling.state_count));
1179
1180         pr->flags.throttling = 1;
1181
1182         /*
1183          * Disable throttling (if enabled).  We'll let subsequent policy (e.g.
1184          * thermal) decide to lower performance if it so chooses, but for now
1185          * we'll crank up the speed.
1186          */
1187
1188         result = acpi_processor_get_throttling(pr);
1189         if (result)
1190                 goto end;
1191
1192         if (pr->throttling.state) {
1193                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1194                                   "Disabling throttling (was T%d)\n",
1195                                   pr->throttling.state));
1196                 result = acpi_processor_set_throttling(pr, 0);
1197                 if (result)
1198                         goto end;
1199         }
1200
1201       end:
1202         if (result)
1203                 pr->flags.throttling = 0;
1204
1205         return result;
1206 }
1207
1208 /* proc interface */
1209
1210 static int acpi_processor_throttling_seq_show(struct seq_file *seq,
1211                                               void *offset)
1212 {
1213         struct acpi_processor *pr = seq->private;
1214         int i = 0;
1215         int result = 0;
1216
1217         if (!pr)
1218                 goto end;
1219
1220         if (!(pr->throttling.state_count > 0)) {
1221                 seq_puts(seq, "<not supported>\n");
1222                 goto end;
1223         }
1224
1225         result = acpi_processor_get_throttling(pr);
1226
1227         if (result) {
1228                 seq_puts(seq,
1229                          "Could not determine current throttling state.\n");
1230                 goto end;
1231         }
1232
1233         seq_printf(seq, "state count:             %d\n"
1234                    "active state:            T%d\n"
1235                    "state available: T%d to T%d\n",
1236                    pr->throttling.state_count, pr->throttling.state,
1237                    pr->throttling_platform_limit,
1238                    pr->throttling.state_count - 1);
1239
1240         seq_puts(seq, "states:\n");
1241         if (pr->throttling.acpi_processor_get_throttling ==
1242                         acpi_processor_get_throttling_fadt) {
1243                 for (i = 0; i < pr->throttling.state_count; i++)
1244                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1245                                    (i == pr->throttling.state ? '*' : ' '), i,
1246                                    (pr->throttling.states[i].performance ? pr->
1247                                     throttling.states[i].performance / 10 : 0));
1248         } else {
1249                 for (i = 0; i < pr->throttling.state_count; i++)
1250                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1251                                    (i == pr->throttling.state ? '*' : ' '), i,
1252                                    (int)pr->throttling.states_tss[i].
1253                                    freqpercentage);
1254         }
1255
1256       end:
1257         return 0;
1258 }
1259
1260 static int acpi_processor_throttling_open_fs(struct inode *inode,
1261                                              struct file *file)
1262 {
1263         return single_open(file, acpi_processor_throttling_seq_show,
1264                            PDE(inode)->data);
1265 }
1266
1267 static ssize_t acpi_processor_write_throttling(struct file *file,
1268                                                const char __user * buffer,
1269                                                size_t count, loff_t * data)
1270 {
1271         int result = 0;
1272         struct seq_file *m = file->private_data;
1273         struct acpi_processor *pr = m->private;
1274         char state_string[5] = "";
1275         char *charp = NULL;
1276         size_t state_val = 0;
1277         char tmpbuf[5] = "";
1278
1279         if (!pr || (count > sizeof(state_string) - 1))
1280                 return -EINVAL;
1281
1282         if (copy_from_user(state_string, buffer, count))
1283                 return -EFAULT;
1284
1285         state_string[count] = '\0';
1286         if ((count > 0) && (state_string[count-1] == '\n'))
1287                 state_string[count-1] = '\0';
1288
1289         charp = state_string;
1290         if ((state_string[0] == 't') || (state_string[0] == 'T'))
1291                 charp++;
1292
1293         state_val = simple_strtoul(charp, NULL, 0);
1294         if (state_val >= pr->throttling.state_count)
1295                 return -EINVAL;
1296
1297         snprintf(tmpbuf, 5, "%zu", state_val);
1298
1299         if (strcmp(tmpbuf, charp) != 0)
1300                 return -EINVAL;
1301
1302         result = acpi_processor_set_throttling(pr, state_val);
1303         if (result)
1304                 return result;
1305
1306         return count;
1307 }
1308
1309 const struct file_operations acpi_processor_throttling_fops = {
1310         .owner = THIS_MODULE,
1311         .open = acpi_processor_throttling_open_fs,
1312         .read = seq_read,
1313         .write = acpi_processor_write_throttling,
1314         .llseek = seq_lseek,
1315         .release = single_release,
1316 };