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