Merge branch 'processor-procfs-2.6.32' into release
[sfrench/cifs-2.6.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 PREFIX "ACPI: "
45
46 #define ACPI_PROCESSOR_CLASS            "processor"
47 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
48 ACPI_MODULE_NAME("processor_throttling");
49
50 /* ignore_tpc:
51  *  0 -> acpi processor driver doesn't ignore _TPC values
52  *  1 -> acpi processor driver ignores _TPC values
53  */
54 static int ignore_tpc;
55 module_param(ignore_tpc, int, 0644);
56 MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
57
58 struct throttling_tstate {
59         unsigned int cpu;               /* cpu nr */
60         int target_state;               /* target T-state */
61 };
62
63 #define THROTTLING_PRECHANGE       (1)
64 #define THROTTLING_POSTCHANGE      (2)
65
66 static int acpi_processor_get_throttling(struct acpi_processor *pr);
67 int acpi_processor_set_throttling(struct acpi_processor *pr,
68                                                 int state, bool force);
69
70 static int acpi_processor_update_tsd_coord(void)
71 {
72         int count, count_target;
73         int retval = 0;
74         unsigned int i, j;
75         cpumask_var_t covered_cpus;
76         struct acpi_processor *pr, *match_pr;
77         struct acpi_tsd_package *pdomain, *match_pdomain;
78         struct acpi_processor_throttling *pthrottling, *match_pthrottling;
79
80         if (!alloc_cpumask_var(&covered_cpus, GFP_KERNEL))
81                 return -ENOMEM;
82
83         /*
84          * Now that we have _TSD data from all CPUs, lets setup T-state
85          * coordination between all CPUs.
86          */
87         for_each_possible_cpu(i) {
88                 pr = per_cpu(processors, i);
89                 if (!pr)
90                         continue;
91
92                 /* Basic validity check for domain info */
93                 pthrottling = &(pr->throttling);
94
95                 /*
96                  * If tsd package for one cpu is invalid, the coordination
97                  * among all CPUs is thought as invalid.
98                  * Maybe it is ugly.
99                  */
100                 if (!pthrottling->tsd_valid_flag) {
101                         retval = -EINVAL;
102                         break;
103                 }
104         }
105         if (retval)
106                 goto err_ret;
107
108         cpumask_clear(covered_cpus);
109         for_each_possible_cpu(i) {
110                 pr = per_cpu(processors, i);
111                 if (!pr)
112                         continue;
113
114                 if (cpumask_test_cpu(i, covered_cpus))
115                         continue;
116                 pthrottling = &pr->throttling;
117
118                 pdomain = &(pthrottling->domain_info);
119                 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
120                 cpumask_set_cpu(i, covered_cpus);
121                 /*
122                  * If the number of processor in the TSD domain is 1, it is
123                  * unnecessary to parse the coordination for this CPU.
124                  */
125                 if (pdomain->num_processors <= 1)
126                         continue;
127
128                 /* Validate the Domain info */
129                 count_target = pdomain->num_processors;
130                 count = 1;
131
132                 for_each_possible_cpu(j) {
133                         if (i == j)
134                                 continue;
135
136                         match_pr = per_cpu(processors, j);
137                         if (!match_pr)
138                                 continue;
139
140                         match_pthrottling = &(match_pr->throttling);
141                         match_pdomain = &(match_pthrottling->domain_info);
142                         if (match_pdomain->domain != pdomain->domain)
143                                 continue;
144
145                         /* Here i and j are in the same domain.
146                          * If two TSD packages have the same domain, they
147                          * should have the same num_porcessors and
148                          * coordination type. Otherwise it will be regarded
149                          * as illegal.
150                          */
151                         if (match_pdomain->num_processors != count_target) {
152                                 retval = -EINVAL;
153                                 goto err_ret;
154                         }
155
156                         if (pdomain->coord_type != match_pdomain->coord_type) {
157                                 retval = -EINVAL;
158                                 goto err_ret;
159                         }
160
161                         cpumask_set_cpu(j, covered_cpus);
162                         cpumask_set_cpu(j, pthrottling->shared_cpu_map);
163                         count++;
164                 }
165                 for_each_possible_cpu(j) {
166                         if (i == j)
167                                 continue;
168
169                         match_pr = per_cpu(processors, j);
170                         if (!match_pr)
171                                 continue;
172
173                         match_pthrottling = &(match_pr->throttling);
174                         match_pdomain = &(match_pthrottling->domain_info);
175                         if (match_pdomain->domain != pdomain->domain)
176                                 continue;
177
178                         /*
179                          * If some CPUS have the same domain, they
180                          * will have the same shared_cpu_map.
181                          */
182                         cpumask_copy(match_pthrottling->shared_cpu_map,
183                                      pthrottling->shared_cpu_map);
184                 }
185         }
186
187 err_ret:
188         free_cpumask_var(covered_cpus);
189
190         for_each_possible_cpu(i) {
191                 pr = per_cpu(processors, i);
192                 if (!pr)
193                         continue;
194
195                 /*
196                  * Assume no coordination on any error parsing domain info.
197                  * The coordination type will be forced as SW_ALL.
198                  */
199                 if (retval) {
200                         pthrottling = &(pr->throttling);
201                         cpumask_clear(pthrottling->shared_cpu_map);
202                         cpumask_set_cpu(i, pthrottling->shared_cpu_map);
203                         pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
204                 }
205         }
206
207         return retval;
208 }
209
210 /*
211  * Update the T-state coordination after the _TSD
212  * data for all cpus is obtained.
213  */
214 void acpi_processor_throttling_init(void)
215 {
216         if (acpi_processor_update_tsd_coord())
217                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
218                         "Assume no T-state coordination\n"));
219
220         return;
221 }
222
223 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
224 {
225         struct throttling_tstate *p_tstate = data;
226         struct acpi_processor *pr;
227         unsigned int cpu ;
228         int target_state;
229         struct acpi_processor_limit *p_limit;
230         struct acpi_processor_throttling *p_throttling;
231
232         cpu = p_tstate->cpu;
233         pr = per_cpu(processors, cpu);
234         if (!pr) {
235                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
236                 return 0;
237         }
238         if (!pr->flags.throttling) {
239                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
240                                 "unsupported on CPU %d\n", cpu));
241                 return 0;
242         }
243         target_state = p_tstate->target_state;
244         p_throttling = &(pr->throttling);
245         switch (event) {
246         case THROTTLING_PRECHANGE:
247                 /*
248                  * Prechange event is used to choose one proper t-state,
249                  * which meets the limits of thermal, user and _TPC.
250                  */
251                 p_limit = &pr->limit;
252                 if (p_limit->thermal.tx > target_state)
253                         target_state = p_limit->thermal.tx;
254                 if (p_limit->user.tx > target_state)
255                         target_state = p_limit->user.tx;
256                 if (pr->throttling_platform_limit > target_state)
257                         target_state = pr->throttling_platform_limit;
258                 if (target_state >= p_throttling->state_count) {
259                         printk(KERN_WARNING
260                                 "Exceed the limit of T-state \n");
261                         target_state = p_throttling->state_count - 1;
262                 }
263                 p_tstate->target_state = target_state;
264                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
265                                 "target T-state of CPU %d is T%d\n",
266                                 cpu, target_state));
267                 break;
268         case THROTTLING_POSTCHANGE:
269                 /*
270                  * Postchange event is only used to update the
271                  * T-state flag of acpi_processor_throttling.
272                  */
273                 p_throttling->state = target_state;
274                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
275                                 "CPU %d is switched to T%d\n",
276                                 cpu, target_state));
277                 break;
278         default:
279                 printk(KERN_WARNING
280                         "Unsupported Throttling notifier event\n");
281                 break;
282         }
283
284         return 0;
285 }
286
287 /*
288  * _TPC - Throttling Present Capabilities
289  */
290 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
291 {
292         acpi_status status = 0;
293         unsigned long long tpc = 0;
294
295         if (!pr)
296                 return -EINVAL;
297
298         if (ignore_tpc)
299                 goto end;
300
301         status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
302         if (ACPI_FAILURE(status)) {
303                 if (status != AE_NOT_FOUND) {
304                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
305                 }
306                 return -ENODEV;
307         }
308
309 end:
310         pr->throttling_platform_limit = (int)tpc;
311         return 0;
312 }
313
314 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
315 {
316         int result = 0;
317         int throttling_limit;
318         int current_state;
319         struct acpi_processor_limit *limit;
320         int target_state;
321
322         if (ignore_tpc)
323                 return 0;
324
325         result = acpi_processor_get_platform_limit(pr);
326         if (result) {
327                 /* Throttling Limit is unsupported */
328                 return result;
329         }
330
331         throttling_limit = pr->throttling_platform_limit;
332         if (throttling_limit >= pr->throttling.state_count) {
333                 /* Uncorrect Throttling Limit */
334                 return -EINVAL;
335         }
336
337         current_state = pr->throttling.state;
338         if (current_state > throttling_limit) {
339                 /*
340                  * The current state can meet the requirement of
341                  * _TPC limit. But it is reasonable that OSPM changes
342                  * t-states from high to low for better performance.
343                  * Of course the limit condition of thermal
344                  * and user should be considered.
345                  */
346                 limit = &pr->limit;
347                 target_state = throttling_limit;
348                 if (limit->thermal.tx > target_state)
349                         target_state = limit->thermal.tx;
350                 if (limit->user.tx > target_state)
351                         target_state = limit->user.tx;
352         } else if (current_state == throttling_limit) {
353                 /*
354                  * Unnecessary to change the throttling state
355                  */
356                 return 0;
357         } else {
358                 /*
359                  * If the current state is lower than the limit of _TPC, it
360                  * will be forced to switch to the throttling state defined
361                  * by throttling_platfor_limit.
362                  * Because the previous state meets with the limit condition
363                  * of thermal and user, it is unnecessary to check it again.
364                  */
365                 target_state = throttling_limit;
366         }
367         return acpi_processor_set_throttling(pr, target_state, false);
368 }
369
370 /*
371  * _PTC - Processor Throttling Control (and status) register location
372  */
373 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
374 {
375         int result = 0;
376         acpi_status status = 0;
377         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
378         union acpi_object *ptc = NULL;
379         union acpi_object obj = { 0 };
380         struct acpi_processor_throttling *throttling;
381
382         status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
383         if (ACPI_FAILURE(status)) {
384                 if (status != AE_NOT_FOUND) {
385                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
386                 }
387                 return -ENODEV;
388         }
389
390         ptc = (union acpi_object *)buffer.pointer;
391         if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
392             || (ptc->package.count != 2)) {
393                 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
394                 result = -EFAULT;
395                 goto end;
396         }
397
398         /*
399          * control_register
400          */
401
402         obj = ptc->package.elements[0];
403
404         if ((obj.type != ACPI_TYPE_BUFFER)
405             || (obj.buffer.length < sizeof(struct acpi_ptc_register))
406             || (obj.buffer.pointer == NULL)) {
407                 printk(KERN_ERR PREFIX
408                        "Invalid _PTC data (control_register)\n");
409                 result = -EFAULT;
410                 goto end;
411         }
412         memcpy(&pr->throttling.control_register, obj.buffer.pointer,
413                sizeof(struct acpi_ptc_register));
414
415         /*
416          * status_register
417          */
418
419         obj = ptc->package.elements[1];
420
421         if ((obj.type != ACPI_TYPE_BUFFER)
422             || (obj.buffer.length < sizeof(struct acpi_ptc_register))
423             || (obj.buffer.pointer == NULL)) {
424                 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
425                 result = -EFAULT;
426                 goto end;
427         }
428
429         memcpy(&pr->throttling.status_register, obj.buffer.pointer,
430                sizeof(struct acpi_ptc_register));
431
432         throttling = &pr->throttling;
433
434         if ((throttling->control_register.bit_width +
435                 throttling->control_register.bit_offset) > 32) {
436                 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
437                 result = -EFAULT;
438                 goto end;
439         }
440
441         if ((throttling->status_register.bit_width +
442                 throttling->status_register.bit_offset) > 32) {
443                 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
444                 result = -EFAULT;
445                 goto end;
446         }
447
448       end:
449         kfree(buffer.pointer);
450
451         return result;
452 }
453
454 /*
455  * _TSS - Throttling Supported States
456  */
457 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
458 {
459         int result = 0;
460         acpi_status status = AE_OK;
461         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
462         struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
463         struct acpi_buffer state = { 0, NULL };
464         union acpi_object *tss = NULL;
465         int i;
466
467         status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
468         if (ACPI_FAILURE(status)) {
469                 if (status != AE_NOT_FOUND) {
470                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
471                 }
472                 return -ENODEV;
473         }
474
475         tss = buffer.pointer;
476         if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
477                 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
478                 result = -EFAULT;
479                 goto end;
480         }
481
482         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
483                           tss->package.count));
484
485         pr->throttling.state_count = tss->package.count;
486         pr->throttling.states_tss =
487             kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
488                     GFP_KERNEL);
489         if (!pr->throttling.states_tss) {
490                 result = -ENOMEM;
491                 goto end;
492         }
493
494         for (i = 0; i < pr->throttling.state_count; i++) {
495
496                 struct acpi_processor_tx_tss *tx =
497                     (struct acpi_processor_tx_tss *)&(pr->throttling.
498                                                       states_tss[i]);
499
500                 state.length = sizeof(struct acpi_processor_tx_tss);
501                 state.pointer = tx;
502
503                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
504
505                 status = acpi_extract_package(&(tss->package.elements[i]),
506                                               &format, &state);
507                 if (ACPI_FAILURE(status)) {
508                         ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
509                         result = -EFAULT;
510                         kfree(pr->throttling.states_tss);
511                         goto end;
512                 }
513
514                 if (!tx->freqpercentage) {
515                         printk(KERN_ERR PREFIX
516                                "Invalid _TSS data: freq is zero\n");
517                         result = -EFAULT;
518                         kfree(pr->throttling.states_tss);
519                         goto end;
520                 }
521         }
522
523       end:
524         kfree(buffer.pointer);
525
526         return result;
527 }
528
529 /*
530  * _TSD - T-State Dependencies
531  */
532 static int acpi_processor_get_tsd(struct acpi_processor *pr)
533 {
534         int result = 0;
535         acpi_status status = AE_OK;
536         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
537         struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
538         struct acpi_buffer state = { 0, NULL };
539         union acpi_object *tsd = NULL;
540         struct acpi_tsd_package *pdomain;
541         struct acpi_processor_throttling *pthrottling;
542
543         pthrottling = &pr->throttling;
544         pthrottling->tsd_valid_flag = 0;
545
546         status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
547         if (ACPI_FAILURE(status)) {
548                 if (status != AE_NOT_FOUND) {
549                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
550                 }
551                 return -ENODEV;
552         }
553
554         tsd = buffer.pointer;
555         if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
556                 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
557                 result = -EFAULT;
558                 goto end;
559         }
560
561         if (tsd->package.count != 1) {
562                 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
563                 result = -EFAULT;
564                 goto end;
565         }
566
567         pdomain = &(pr->throttling.domain_info);
568
569         state.length = sizeof(struct acpi_tsd_package);
570         state.pointer = pdomain;
571
572         status = acpi_extract_package(&(tsd->package.elements[0]),
573                                       &format, &state);
574         if (ACPI_FAILURE(status)) {
575                 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
576                 result = -EFAULT;
577                 goto end;
578         }
579
580         if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
581                 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
582                 result = -EFAULT;
583                 goto end;
584         }
585
586         if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
587                 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
588                 result = -EFAULT;
589                 goto end;
590         }
591
592         pthrottling = &pr->throttling;
593         pthrottling->tsd_valid_flag = 1;
594         pthrottling->shared_type = pdomain->coord_type;
595         cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
596         /*
597          * If the coordination type is not defined in ACPI spec,
598          * the tsd_valid_flag will be clear and coordination type
599          * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
600          */
601         if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
602                 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
603                 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
604                 pthrottling->tsd_valid_flag = 0;
605                 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
606         }
607
608       end:
609         kfree(buffer.pointer);
610         return result;
611 }
612
613 /* --------------------------------------------------------------------------
614                               Throttling Control
615    -------------------------------------------------------------------------- */
616 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
617 {
618         int state = 0;
619         u32 value = 0;
620         u32 duty_mask = 0;
621         u32 duty_value = 0;
622
623         if (!pr)
624                 return -EINVAL;
625
626         if (!pr->flags.throttling)
627                 return -ENODEV;
628
629         pr->throttling.state = 0;
630
631         duty_mask = pr->throttling.state_count - 1;
632
633         duty_mask <<= pr->throttling.duty_offset;
634
635         local_irq_disable();
636
637         value = inl(pr->throttling.address);
638
639         /*
640          * Compute the current throttling state when throttling is enabled
641          * (bit 4 is on).
642          */
643         if (value & 0x10) {
644                 duty_value = value & duty_mask;
645                 duty_value >>= pr->throttling.duty_offset;
646
647                 if (duty_value)
648                         state = pr->throttling.state_count - duty_value;
649         }
650
651         pr->throttling.state = state;
652
653         local_irq_enable();
654
655         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
656                           "Throttling state is T%d (%d%% throttling applied)\n",
657                           state, pr->throttling.states[state].performance));
658
659         return 0;
660 }
661
662 #ifdef CONFIG_X86
663 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
664                                         acpi_integer * value)
665 {
666         struct cpuinfo_x86 *c;
667         u64 msr_high, msr_low;
668         unsigned int cpu;
669         u64 msr = 0;
670         int ret = -1;
671
672         cpu = pr->id;
673         c = &cpu_data(cpu);
674
675         if ((c->x86_vendor != X86_VENDOR_INTEL) ||
676                 !cpu_has(c, X86_FEATURE_ACPI)) {
677                 printk(KERN_ERR PREFIX
678                         "HARDWARE addr space,NOT supported yet\n");
679         } else {
680                 msr_low = 0;
681                 msr_high = 0;
682                 rdmsr_safe(MSR_IA32_THERM_CONTROL,
683                         (u32 *)&msr_low , (u32 *) &msr_high);
684                 msr = (msr_high << 32) | msr_low;
685                 *value = (acpi_integer) msr;
686                 ret = 0;
687         }
688         return ret;
689 }
690
691 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
692 {
693         struct cpuinfo_x86 *c;
694         unsigned int cpu;
695         int ret = -1;
696         u64 msr;
697
698         cpu = pr->id;
699         c = &cpu_data(cpu);
700
701         if ((c->x86_vendor != X86_VENDOR_INTEL) ||
702                 !cpu_has(c, X86_FEATURE_ACPI)) {
703                 printk(KERN_ERR PREFIX
704                         "HARDWARE addr space,NOT supported yet\n");
705         } else {
706                 msr = value;
707                 wrmsr_safe(MSR_IA32_THERM_CONTROL,
708                         msr & 0xffffffff, msr >> 32);
709                 ret = 0;
710         }
711         return ret;
712 }
713 #else
714 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
715                                 acpi_integer * value)
716 {
717         printk(KERN_ERR PREFIX
718                 "HARDWARE addr space,NOT supported yet\n");
719         return -1;
720 }
721
722 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
723 {
724         printk(KERN_ERR PREFIX
725                 "HARDWARE addr space,NOT supported yet\n");
726         return -1;
727 }
728 #endif
729
730 static int acpi_read_throttling_status(struct acpi_processor *pr,
731                                         acpi_integer *value)
732 {
733         u32 bit_width, bit_offset;
734         u64 ptc_value;
735         u64 ptc_mask;
736         struct acpi_processor_throttling *throttling;
737         int ret = -1;
738
739         throttling = &pr->throttling;
740         switch (throttling->status_register.space_id) {
741         case ACPI_ADR_SPACE_SYSTEM_IO:
742                 ptc_value = 0;
743                 bit_width = throttling->status_register.bit_width;
744                 bit_offset = throttling->status_register.bit_offset;
745
746                 acpi_os_read_port((acpi_io_address) throttling->status_register.
747                                   address, (u32 *) &ptc_value,
748                                   (u32) (bit_width + bit_offset));
749                 ptc_mask = (1 << bit_width) - 1;
750                 *value = (acpi_integer) ((ptc_value >> bit_offset) & ptc_mask);
751                 ret = 0;
752                 break;
753         case ACPI_ADR_SPACE_FIXED_HARDWARE:
754                 ret = acpi_throttling_rdmsr(pr, value);
755                 break;
756         default:
757                 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
758                        (u32) (throttling->status_register.space_id));
759         }
760         return ret;
761 }
762
763 static int acpi_write_throttling_state(struct acpi_processor *pr,
764                                 acpi_integer value)
765 {
766         u32 bit_width, bit_offset;
767         u64 ptc_value;
768         u64 ptc_mask;
769         struct acpi_processor_throttling *throttling;
770         int ret = -1;
771
772         throttling = &pr->throttling;
773         switch (throttling->control_register.space_id) {
774         case ACPI_ADR_SPACE_SYSTEM_IO:
775                 bit_width = throttling->control_register.bit_width;
776                 bit_offset = throttling->control_register.bit_offset;
777                 ptc_mask = (1 << bit_width) - 1;
778                 ptc_value = value & ptc_mask;
779
780                 acpi_os_write_port((acpi_io_address) throttling->
781                                         control_register.address,
782                                         (u32) (ptc_value << bit_offset),
783                                         (u32) (bit_width + bit_offset));
784                 ret = 0;
785                 break;
786         case ACPI_ADR_SPACE_FIXED_HARDWARE:
787                 ret = acpi_throttling_wrmsr(pr, value);
788                 break;
789         default:
790                 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
791                        (u32) (throttling->control_register.space_id));
792         }
793         return ret;
794 }
795
796 static int acpi_get_throttling_state(struct acpi_processor *pr,
797                                 acpi_integer value)
798 {
799         int i;
800
801         for (i = 0; i < pr->throttling.state_count; i++) {
802                 struct acpi_processor_tx_tss *tx =
803                     (struct acpi_processor_tx_tss *)&(pr->throttling.
804                                                       states_tss[i]);
805                 if (tx->control == value)
806                         return i;
807         }
808         return -1;
809 }
810
811 static int acpi_get_throttling_value(struct acpi_processor *pr,
812                         int state, acpi_integer *value)
813 {
814         int ret = -1;
815
816         if (state >= 0 && state <= pr->throttling.state_count) {
817                 struct acpi_processor_tx_tss *tx =
818                     (struct acpi_processor_tx_tss *)&(pr->throttling.
819                                                       states_tss[state]);
820                 *value = tx->control;
821                 ret = 0;
822         }
823         return ret;
824 }
825
826 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
827 {
828         int state = 0;
829         int ret;
830         acpi_integer value;
831
832         if (!pr)
833                 return -EINVAL;
834
835         if (!pr->flags.throttling)
836                 return -ENODEV;
837
838         pr->throttling.state = 0;
839
840         value = 0;
841         ret = acpi_read_throttling_status(pr, &value);
842         if (ret >= 0) {
843                 state = acpi_get_throttling_state(pr, value);
844                 if (state == -1) {
845                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
846                                 "Invalid throttling state, reset\n"));
847                         state = 0;
848                         ret = acpi_processor_set_throttling(pr, state, true);
849                         if (ret)
850                                 return ret;
851                 }
852                 pr->throttling.state = state;
853         }
854
855         return 0;
856 }
857
858 static int acpi_processor_get_throttling(struct acpi_processor *pr)
859 {
860         cpumask_var_t saved_mask;
861         int ret;
862
863         if (!pr)
864                 return -EINVAL;
865
866         if (!pr->flags.throttling)
867                 return -ENODEV;
868
869         if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
870                 return -ENOMEM;
871
872         /*
873          * Migrate task to the cpu pointed by pr.
874          */
875         cpumask_copy(saved_mask, &current->cpus_allowed);
876         /* FIXME: use work_on_cpu() */
877         set_cpus_allowed_ptr(current, cpumask_of(pr->id));
878         ret = pr->throttling.acpi_processor_get_throttling(pr);
879         /* restore the previous state */
880         set_cpus_allowed_ptr(current, saved_mask);
881         free_cpumask_var(saved_mask);
882
883         return ret;
884 }
885
886 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
887 {
888         int i, step;
889
890         if (!pr->throttling.address) {
891                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
892                 return -EINVAL;
893         } else if (!pr->throttling.duty_width) {
894                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
895                 return -EINVAL;
896         }
897         /* TBD: Support duty_cycle values that span bit 4. */
898         else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
899                 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
900                 return -EINVAL;
901         }
902
903         pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
904
905         /*
906          * Compute state values. Note that throttling displays a linear power
907          * performance relationship (at 50% performance the CPU will consume
908          * 50% power).  Values are in 1/10th of a percent to preserve accuracy.
909          */
910
911         step = (1000 / pr->throttling.state_count);
912
913         for (i = 0; i < pr->throttling.state_count; i++) {
914                 pr->throttling.states[i].performance = 1000 - step * i;
915                 pr->throttling.states[i].power = 1000 - step * i;
916         }
917         return 0;
918 }
919
920 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
921                                               int state, bool force)
922 {
923         u32 value = 0;
924         u32 duty_mask = 0;
925         u32 duty_value = 0;
926
927         if (!pr)
928                 return -EINVAL;
929
930         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
931                 return -EINVAL;
932
933         if (!pr->flags.throttling)
934                 return -ENODEV;
935
936         if (!force && (state == pr->throttling.state))
937                 return 0;
938
939         if (state < pr->throttling_platform_limit)
940                 return -EPERM;
941         /*
942          * Calculate the duty_value and duty_mask.
943          */
944         if (state) {
945                 duty_value = pr->throttling.state_count - state;
946
947                 duty_value <<= pr->throttling.duty_offset;
948
949                 /* Used to clear all duty_value bits */
950                 duty_mask = pr->throttling.state_count - 1;
951
952                 duty_mask <<= acpi_gbl_FADT.duty_offset;
953                 duty_mask = ~duty_mask;
954         }
955
956         local_irq_disable();
957
958         /*
959          * Disable throttling by writing a 0 to bit 4.  Note that we must
960          * turn it off before you can change the duty_value.
961          */
962         value = inl(pr->throttling.address);
963         if (value & 0x10) {
964                 value &= 0xFFFFFFEF;
965                 outl(value, pr->throttling.address);
966         }
967
968         /*
969          * Write the new duty_value and then enable throttling.  Note
970          * that a state value of 0 leaves throttling disabled.
971          */
972         if (state) {
973                 value &= duty_mask;
974                 value |= duty_value;
975                 outl(value, pr->throttling.address);
976
977                 value |= 0x00000010;
978                 outl(value, pr->throttling.address);
979         }
980
981         pr->throttling.state = state;
982
983         local_irq_enable();
984
985         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
986                           "Throttling state set to T%d (%d%%)\n", state,
987                           (pr->throttling.states[state].performance ? pr->
988                            throttling.states[state].performance / 10 : 0)));
989
990         return 0;
991 }
992
993 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
994                                              int state, bool force)
995 {
996         int ret;
997         acpi_integer value;
998
999         if (!pr)
1000                 return -EINVAL;
1001
1002         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1003                 return -EINVAL;
1004
1005         if (!pr->flags.throttling)
1006                 return -ENODEV;
1007
1008         if (!force && (state == pr->throttling.state))
1009                 return 0;
1010
1011         if (state < pr->throttling_platform_limit)
1012                 return -EPERM;
1013
1014         value = 0;
1015         ret = acpi_get_throttling_value(pr, state, &value);
1016         if (ret >= 0) {
1017                 acpi_write_throttling_state(pr, value);
1018                 pr->throttling.state = state;
1019         }
1020
1021         return 0;
1022 }
1023
1024 int acpi_processor_set_throttling(struct acpi_processor *pr,
1025                                                 int state, bool force)
1026 {
1027         cpumask_var_t saved_mask;
1028         int ret = 0;
1029         unsigned int i;
1030         struct acpi_processor *match_pr;
1031         struct acpi_processor_throttling *p_throttling;
1032         struct throttling_tstate t_state;
1033         cpumask_var_t online_throttling_cpus;
1034
1035         if (!pr)
1036                 return -EINVAL;
1037
1038         if (!pr->flags.throttling)
1039                 return -ENODEV;
1040
1041         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1042                 return -EINVAL;
1043
1044         if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1045                 return -ENOMEM;
1046
1047         if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1048                 free_cpumask_var(saved_mask);
1049                 return -ENOMEM;
1050         }
1051
1052         cpumask_copy(saved_mask, &current->cpus_allowed);
1053         t_state.target_state = state;
1054         p_throttling = &(pr->throttling);
1055         cpumask_and(online_throttling_cpus, cpu_online_mask,
1056                     p_throttling->shared_cpu_map);
1057         /*
1058          * The throttling notifier will be called for every
1059          * affected cpu in order to get one proper T-state.
1060          * The notifier event is THROTTLING_PRECHANGE.
1061          */
1062         for_each_cpu(i, online_throttling_cpus) {
1063                 t_state.cpu = i;
1064                 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1065                                                         &t_state);
1066         }
1067         /*
1068          * The function of acpi_processor_set_throttling will be called
1069          * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1070          * it is necessary to call it for every affected cpu. Otherwise
1071          * it can be called only for the cpu pointed by pr.
1072          */
1073         if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1074                 /* FIXME: use work_on_cpu() */
1075                 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
1076                 ret = p_throttling->acpi_processor_set_throttling(pr,
1077                                                 t_state.target_state, force);
1078         } else {
1079                 /*
1080                  * When the T-state coordination is SW_ALL or HW_ALL,
1081                  * it is necessary to set T-state for every affected
1082                  * cpus.
1083                  */
1084                 for_each_cpu(i, online_throttling_cpus) {
1085                         match_pr = per_cpu(processors, i);
1086                         /*
1087                          * If the pointer is invalid, we will report the
1088                          * error message and continue.
1089                          */
1090                         if (!match_pr) {
1091                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1092                                         "Invalid Pointer for CPU %d\n", i));
1093                                 continue;
1094                         }
1095                         /*
1096                          * If the throttling control is unsupported on CPU i,
1097                          * we will report the error message and continue.
1098                          */
1099                         if (!match_pr->flags.throttling) {
1100                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1101                                         "Throttling Controll is unsupported "
1102                                         "on CPU %d\n", i));
1103                                 continue;
1104                         }
1105                         t_state.cpu = i;
1106                         /* FIXME: use work_on_cpu() */
1107                         set_cpus_allowed_ptr(current, cpumask_of(i));
1108                         ret = match_pr->throttling.
1109                                 acpi_processor_set_throttling(
1110                                 match_pr, t_state.target_state, force);
1111                 }
1112         }
1113         /*
1114          * After the set_throttling is called, the
1115          * throttling notifier is called for every
1116          * affected cpu to update the T-states.
1117          * The notifier event is THROTTLING_POSTCHANGE
1118          */
1119         for_each_cpu(i, online_throttling_cpus) {
1120                 t_state.cpu = i;
1121                 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1122                                                         &t_state);
1123         }
1124         /* restore the previous state */
1125         /* FIXME: use work_on_cpu() */
1126         set_cpus_allowed_ptr(current, saved_mask);
1127         free_cpumask_var(online_throttling_cpus);
1128         free_cpumask_var(saved_mask);
1129         return ret;
1130 }
1131
1132 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1133 {
1134         int result = 0;
1135         struct acpi_processor_throttling *pthrottling;
1136
1137         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1138                           "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1139                           pr->throttling.address,
1140                           pr->throttling.duty_offset,
1141                           pr->throttling.duty_width));
1142
1143         if (!pr)
1144                 return -EINVAL;
1145
1146         /*
1147          * Evaluate _PTC, _TSS and _TPC
1148          * They must all be present or none of them can be used.
1149          */
1150         if (acpi_processor_get_throttling_control(pr) ||
1151                 acpi_processor_get_throttling_states(pr) ||
1152                 acpi_processor_get_platform_limit(pr))
1153         {
1154                 pr->throttling.acpi_processor_get_throttling =
1155                     &acpi_processor_get_throttling_fadt;
1156                 pr->throttling.acpi_processor_set_throttling =
1157                     &acpi_processor_set_throttling_fadt;
1158                 if (acpi_processor_get_fadt_info(pr))
1159                         return 0;
1160         } else {
1161                 pr->throttling.acpi_processor_get_throttling =
1162                     &acpi_processor_get_throttling_ptc;
1163                 pr->throttling.acpi_processor_set_throttling =
1164                     &acpi_processor_set_throttling_ptc;
1165         }
1166
1167         /*
1168          * If TSD package for one CPU can't be parsed successfully, it means
1169          * that this CPU will have no coordination with other CPUs.
1170          */
1171         if (acpi_processor_get_tsd(pr)) {
1172                 pthrottling = &pr->throttling;
1173                 pthrottling->tsd_valid_flag = 0;
1174                 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1175                 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1176         }
1177
1178         /*
1179          * PIIX4 Errata: We don't support throttling on the original PIIX4.
1180          * This shouldn't be an issue as few (if any) mobile systems ever
1181          * used this part.
1182          */
1183         if (errata.piix4.throttle) {
1184                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1185                                   "Throttling not supported on PIIX4 A- or B-step\n"));
1186                 return 0;
1187         }
1188
1189         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1190                           pr->throttling.state_count));
1191
1192         pr->flags.throttling = 1;
1193
1194         /*
1195          * Disable throttling (if enabled).  We'll let subsequent policy (e.g.
1196          * thermal) decide to lower performance if it so chooses, but for now
1197          * we'll crank up the speed.
1198          */
1199
1200         result = acpi_processor_get_throttling(pr);
1201         if (result)
1202                 goto end;
1203
1204         if (pr->throttling.state) {
1205                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1206                                   "Disabling throttling (was T%d)\n",
1207                                   pr->throttling.state));
1208                 result = acpi_processor_set_throttling(pr, 0, false);
1209                 if (result)
1210                         goto end;
1211         }
1212
1213       end:
1214         if (result)
1215                 pr->flags.throttling = 0;
1216
1217         return result;
1218 }
1219
1220 /* proc interface */
1221 #ifdef CONFIG_ACPI_PROCFS
1222 static int acpi_processor_throttling_seq_show(struct seq_file *seq,
1223                                               void *offset)
1224 {
1225         struct acpi_processor *pr = seq->private;
1226         int i = 0;
1227         int result = 0;
1228
1229         if (!pr)
1230                 goto end;
1231
1232         if (!(pr->throttling.state_count > 0)) {
1233                 seq_puts(seq, "<not supported>\n");
1234                 goto end;
1235         }
1236
1237         result = acpi_processor_get_throttling(pr);
1238
1239         if (result) {
1240                 seq_puts(seq,
1241                          "Could not determine current throttling state.\n");
1242                 goto end;
1243         }
1244
1245         seq_printf(seq, "state count:             %d\n"
1246                    "active state:            T%d\n"
1247                    "state available: T%d to T%d\n",
1248                    pr->throttling.state_count, pr->throttling.state,
1249                    pr->throttling_platform_limit,
1250                    pr->throttling.state_count - 1);
1251
1252         seq_puts(seq, "states:\n");
1253         if (pr->throttling.acpi_processor_get_throttling ==
1254                         acpi_processor_get_throttling_fadt) {
1255                 for (i = 0; i < pr->throttling.state_count; i++)
1256                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1257                                    (i == pr->throttling.state ? '*' : ' '), i,
1258                                    (pr->throttling.states[i].performance ? pr->
1259                                     throttling.states[i].performance / 10 : 0));
1260         } else {
1261                 for (i = 0; i < pr->throttling.state_count; i++)
1262                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1263                                    (i == pr->throttling.state ? '*' : ' '), i,
1264                                    (int)pr->throttling.states_tss[i].
1265                                    freqpercentage);
1266         }
1267
1268       end:
1269         return 0;
1270 }
1271
1272 static int acpi_processor_throttling_open_fs(struct inode *inode,
1273                                              struct file *file)
1274 {
1275         return single_open(file, acpi_processor_throttling_seq_show,
1276                            PDE(inode)->data);
1277 }
1278
1279 static ssize_t acpi_processor_write_throttling(struct file *file,
1280                                                const char __user * buffer,
1281                                                size_t count, loff_t * data)
1282 {
1283         int result = 0;
1284         struct seq_file *m = file->private_data;
1285         struct acpi_processor *pr = m->private;
1286         char state_string[5] = "";
1287         char *charp = NULL;
1288         size_t state_val = 0;
1289         char tmpbuf[5] = "";
1290
1291         if (!pr || (count > sizeof(state_string) - 1))
1292                 return -EINVAL;
1293
1294         if (copy_from_user(state_string, buffer, count))
1295                 return -EFAULT;
1296
1297         state_string[count] = '\0';
1298         if ((count > 0) && (state_string[count-1] == '\n'))
1299                 state_string[count-1] = '\0';
1300
1301         charp = state_string;
1302         if ((state_string[0] == 't') || (state_string[0] == 'T'))
1303                 charp++;
1304
1305         state_val = simple_strtoul(charp, NULL, 0);
1306         if (state_val >= pr->throttling.state_count)
1307                 return -EINVAL;
1308
1309         snprintf(tmpbuf, 5, "%zu", state_val);
1310
1311         if (strcmp(tmpbuf, charp) != 0)
1312                 return -EINVAL;
1313
1314         result = acpi_processor_set_throttling(pr, state_val, false);
1315         if (result)
1316                 return result;
1317
1318         return count;
1319 }
1320
1321 const struct file_operations acpi_processor_throttling_fops = {
1322         .owner = THIS_MODULE,
1323         .open = acpi_processor_throttling_open_fs,
1324         .read = seq_read,
1325         .write = acpi_processor_write_throttling,
1326         .llseek = seq_lseek,
1327         .release = single_release,
1328 };
1329 #endif