ff3632717c5140bd7c8692e0055b74681ece037c
[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/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