acpi: use non-racy method for proc entries creation
[linux-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/processor.h>
42
43 #define ACPI_PROCESSOR_COMPONENT        0x01000000
44 #define ACPI_PROCESSOR_CLASS            "processor"
45 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
46 ACPI_MODULE_NAME("processor_throttling");
47
48 struct throttling_tstate {
49         unsigned int cpu;               /* cpu nr */
50         int target_state;               /* target T-state */
51 };
52
53 #define THROTTLING_PRECHANGE       (1)
54 #define THROTTLING_POSTCHANGE      (2)
55
56 static int acpi_processor_get_throttling(struct acpi_processor *pr);
57 int acpi_processor_set_throttling(struct acpi_processor *pr, int state);
58
59 static int acpi_processor_update_tsd_coord(void)
60 {
61         int count, count_target;
62         int retval = 0;
63         unsigned int i, j;
64         cpumask_t covered_cpus;
65         struct acpi_processor *pr, *match_pr;
66         struct acpi_tsd_package *pdomain, *match_pdomain;
67         struct acpi_processor_throttling *pthrottling, *match_pthrottling;
68
69         /*
70          * Now that we have _TSD data from all CPUs, lets setup T-state
71          * coordination between all CPUs.
72          */
73         for_each_possible_cpu(i) {
74                 pr = processors[i];
75                 if (!pr)
76                         continue;
77
78                 /* Basic validity check for domain info */
79                 pthrottling = &(pr->throttling);
80
81                 /*
82                  * If tsd package for one cpu is invalid, the coordination
83                  * among all CPUs is thought as invalid.
84                  * Maybe it is ugly.
85                  */
86                 if (!pthrottling->tsd_valid_flag) {
87                         retval = -EINVAL;
88                         break;
89                 }
90         }
91         if (retval)
92                 goto err_ret;
93
94         cpus_clear(covered_cpus);
95         for_each_possible_cpu(i) {
96                 pr = processors[i];
97                 if (!pr)
98                         continue;
99
100                 if (cpu_isset(i, covered_cpus))
101                         continue;
102                 pthrottling = &pr->throttling;
103
104                 pdomain = &(pthrottling->domain_info);
105                 cpu_set(i, pthrottling->shared_cpu_map);
106                 cpu_set(i, covered_cpus);
107                 /*
108                  * If the number of processor in the TSD domain is 1, it is
109                  * unnecessary to parse the coordination for this CPU.
110                  */
111                 if (pdomain->num_processors <= 1)
112                         continue;
113
114                 /* Validate the Domain info */
115                 count_target = pdomain->num_processors;
116                 count = 1;
117
118                 for_each_possible_cpu(j) {
119                         if (i == j)
120                                 continue;
121
122                         match_pr = processors[j];
123                         if (!match_pr)
124                                 continue;
125
126                         match_pthrottling = &(match_pr->throttling);
127                         match_pdomain = &(match_pthrottling->domain_info);
128                         if (match_pdomain->domain != pdomain->domain)
129                                 continue;
130
131                         /* Here i and j are in the same domain.
132                          * If two TSD packages have the same domain, they
133                          * should have the same num_porcessors and
134                          * coordination type. Otherwise it will be regarded
135                          * as illegal.
136                          */
137                         if (match_pdomain->num_processors != count_target) {
138                                 retval = -EINVAL;
139                                 goto err_ret;
140                         }
141
142                         if (pdomain->coord_type != match_pdomain->coord_type) {
143                                 retval = -EINVAL;
144                                 goto err_ret;
145                         }
146
147                         cpu_set(j, covered_cpus);
148                         cpu_set(j, pthrottling->shared_cpu_map);
149                         count++;
150                 }
151                 for_each_possible_cpu(j) {
152                         if (i == j)
153                                 continue;
154
155                         match_pr = processors[j];
156                         if (!match_pr)
157                                 continue;
158
159                         match_pthrottling = &(match_pr->throttling);
160                         match_pdomain = &(match_pthrottling->domain_info);
161                         if (match_pdomain->domain != pdomain->domain)
162                                 continue;
163
164                         /*
165                          * If some CPUS have the same domain, they
166                          * will have the same shared_cpu_map.
167                          */
168                         match_pthrottling->shared_cpu_map =
169                                 pthrottling->shared_cpu_map;
170                 }
171         }
172
173 err_ret:
174         for_each_possible_cpu(i) {
175                 pr = processors[i];
176                 if (!pr)
177                         continue;
178
179                 /*
180                  * Assume no coordination on any error parsing domain info.
181                  * The coordination type will be forced as SW_ALL.
182                  */
183                 if (retval) {
184                         pthrottling = &(pr->throttling);
185                         cpus_clear(pthrottling->shared_cpu_map);
186                         cpu_set(i, pthrottling->shared_cpu_map);
187                         pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
188                 }
189         }
190
191         return retval;
192 }
193
194 /*
195  * Update the T-state coordination after the _TSD
196  * data for all cpus is obtained.
197  */
198 void acpi_processor_throttling_init(void)
199 {
200         if (acpi_processor_update_tsd_coord())
201                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
202                         "Assume no T-state coordination\n"));
203
204         return;
205 }
206
207 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
208 {
209         struct throttling_tstate *p_tstate = data;
210         struct acpi_processor *pr;
211         unsigned int cpu ;
212         int target_state;
213         struct acpi_processor_limit *p_limit;
214         struct acpi_processor_throttling *p_throttling;
215
216         cpu = p_tstate->cpu;
217         pr = processors[cpu];
218         if (!pr) {
219                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
220                 return 0;
221         }
222         if (!pr->flags.throttling) {
223                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
224                                 "unsupported on CPU %d\n", cpu));
225                 return 0;
226         }
227         target_state = p_tstate->target_state;
228         p_throttling = &(pr->throttling);
229         switch (event) {
230         case THROTTLING_PRECHANGE:
231                 /*
232                  * Prechange event is used to choose one proper t-state,
233                  * which meets the limits of thermal, user and _TPC.
234                  */
235                 p_limit = &pr->limit;
236                 if (p_limit->thermal.tx > target_state)
237                         target_state = p_limit->thermal.tx;
238                 if (p_limit->user.tx > target_state)
239                         target_state = p_limit->user.tx;
240                 if (pr->throttling_platform_limit > target_state)
241                         target_state = pr->throttling_platform_limit;
242                 if (target_state >= p_throttling->state_count) {
243                         printk(KERN_WARNING
244                                 "Exceed the limit of T-state \n");
245                         target_state = p_throttling->state_count - 1;
246                 }
247                 p_tstate->target_state = target_state;
248                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
249                                 "target T-state of CPU %d is T%d\n",
250                                 cpu, target_state));
251                 break;
252         case THROTTLING_POSTCHANGE:
253                 /*
254                  * Postchange event is only used to update the
255                  * T-state flag of acpi_processor_throttling.
256                  */
257                 p_throttling->state = target_state;
258                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
259                                 "CPU %d is switched to T%d\n",
260                                 cpu, target_state));
261                 break;
262         default:
263                 printk(KERN_WARNING
264                         "Unsupported Throttling notifier event\n");
265                 break;
266         }
267
268         return 0;
269 }
270
271 /*
272  * _TPC - Throttling Present Capabilities
273  */
274 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
275 {
276         acpi_status status = 0;
277         unsigned long tpc = 0;
278
279         if (!pr)
280                 return -EINVAL;
281         status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
282         if (ACPI_FAILURE(status)) {
283                 if (status != AE_NOT_FOUND) {
284                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
285                 }
286                 return -ENODEV;
287         }
288         pr->throttling_platform_limit = (int)tpc;
289         return 0;
290 }
291
292 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
293 {
294         int result = 0;
295         int throttling_limit;
296         int current_state;
297         struct acpi_processor_limit *limit;
298         int target_state;
299
300         result = acpi_processor_get_platform_limit(pr);
301         if (result) {
302                 /* Throttling Limit is unsupported */
303                 return result;
304         }
305
306         throttling_limit = pr->throttling_platform_limit;
307         if (throttling_limit >= pr->throttling.state_count) {
308                 /* Uncorrect Throttling Limit */
309                 return -EINVAL;
310         }
311
312         current_state = pr->throttling.state;
313         if (current_state > throttling_limit) {
314                 /*
315                  * The current state can meet the requirement of
316                  * _TPC limit. But it is reasonable that OSPM changes
317                  * t-states from high to low for better performance.
318                  * Of course the limit condition of thermal
319                  * and user should be considered.
320                  */
321                 limit = &pr->limit;
322                 target_state = throttling_limit;
323                 if (limit->thermal.tx > target_state)
324                         target_state = limit->thermal.tx;
325                 if (limit->user.tx > target_state)
326                         target_state = limit->user.tx;
327         } else if (current_state == throttling_limit) {
328                 /*
329                  * Unnecessary to change the throttling state
330                  */
331                 return 0;
332         } else {
333                 /*
334                  * If the current state is lower than the limit of _TPC, it
335                  * will be forced to switch to the throttling state defined
336                  * by throttling_platfor_limit.
337                  * Because the previous state meets with the limit condition
338                  * of thermal and user, it is unnecessary to check it again.
339                  */
340                 target_state = throttling_limit;
341         }
342         return acpi_processor_set_throttling(pr, target_state);
343 }
344
345 /*
346  * _PTC - Processor Throttling Control (and status) register location
347  */
348 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
349 {
350         int result = 0;
351         acpi_status status = 0;
352         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
353         union acpi_object *ptc = NULL;
354         union acpi_object obj = { 0 };
355         struct acpi_processor_throttling *throttling;
356
357         status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
358         if (ACPI_FAILURE(status)) {
359                 if (status != AE_NOT_FOUND) {
360                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
361                 }
362                 return -ENODEV;
363         }
364
365         ptc = (union acpi_object *)buffer.pointer;
366         if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
367             || (ptc->package.count != 2)) {
368                 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
369                 result = -EFAULT;
370                 goto end;
371         }
372
373         /*
374          * control_register
375          */
376
377         obj = ptc->package.elements[0];
378
379         if ((obj.type != ACPI_TYPE_BUFFER)
380             || (obj.buffer.length < sizeof(struct acpi_ptc_register))
381             || (obj.buffer.pointer == NULL)) {
382                 printk(KERN_ERR PREFIX
383                        "Invalid _PTC data (control_register)\n");
384                 result = -EFAULT;
385                 goto end;
386         }
387         memcpy(&pr->throttling.control_register, obj.buffer.pointer,
388                sizeof(struct acpi_ptc_register));
389
390         /*
391          * status_register
392          */
393
394         obj = ptc->package.elements[1];
395
396         if ((obj.type != ACPI_TYPE_BUFFER)
397             || (obj.buffer.length < sizeof(struct acpi_ptc_register))
398             || (obj.buffer.pointer == NULL)) {
399                 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
400                 result = -EFAULT;
401                 goto end;
402         }
403
404         memcpy(&pr->throttling.status_register, obj.buffer.pointer,
405                sizeof(struct acpi_ptc_register));
406
407         throttling = &pr->throttling;
408
409         if ((throttling->control_register.bit_width +
410                 throttling->control_register.bit_offset) > 32) {
411                 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
412                 result = -EFAULT;
413                 goto end;
414         }
415
416         if ((throttling->status_register.bit_width +
417                 throttling->status_register.bit_offset) > 32) {
418                 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
419                 result = -EFAULT;
420                 goto end;
421         }
422
423       end:
424         kfree(buffer.pointer);
425
426         return result;
427 }
428
429 /*
430  * _TSS - Throttling Supported States
431  */
432 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
433 {
434         int result = 0;
435         acpi_status status = AE_OK;
436         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
437         struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
438         struct acpi_buffer state = { 0, NULL };
439         union acpi_object *tss = NULL;
440         int i;
441
442         status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
443         if (ACPI_FAILURE(status)) {
444                 if (status != AE_NOT_FOUND) {
445                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
446                 }
447                 return -ENODEV;
448         }
449
450         tss = buffer.pointer;
451         if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
452                 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
453                 result = -EFAULT;
454                 goto end;
455         }
456
457         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
458                           tss->package.count));
459
460         pr->throttling.state_count = tss->package.count;
461         pr->throttling.states_tss =
462             kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
463                     GFP_KERNEL);
464         if (!pr->throttling.states_tss) {
465                 result = -ENOMEM;
466                 goto end;
467         }
468
469         for (i = 0; i < pr->throttling.state_count; i++) {
470
471                 struct acpi_processor_tx_tss *tx =
472                     (struct acpi_processor_tx_tss *)&(pr->throttling.
473                                                       states_tss[i]);
474
475                 state.length = sizeof(struct acpi_processor_tx_tss);
476                 state.pointer = tx;
477
478                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
479
480                 status = acpi_extract_package(&(tss->package.elements[i]),
481                                               &format, &state);
482                 if (ACPI_FAILURE(status)) {
483                         ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
484                         result = -EFAULT;
485                         kfree(pr->throttling.states_tss);
486                         goto end;
487                 }
488
489                 if (!tx->freqpercentage) {
490                         printk(KERN_ERR PREFIX
491                                "Invalid _TSS data: freq is zero\n");
492                         result = -EFAULT;
493                         kfree(pr->throttling.states_tss);
494                         goto end;
495                 }
496         }
497
498       end:
499         kfree(buffer.pointer);
500
501         return result;
502 }
503
504 /*
505  * _TSD - T-State Dependencies
506  */
507 static int acpi_processor_get_tsd(struct acpi_processor *pr)
508 {
509         int result = 0;
510         acpi_status status = AE_OK;
511         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
512         struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
513         struct acpi_buffer state = { 0, NULL };
514         union acpi_object *tsd = NULL;
515         struct acpi_tsd_package *pdomain;
516         struct acpi_processor_throttling *pthrottling;
517
518         pthrottling = &pr->throttling;
519         pthrottling->tsd_valid_flag = 0;
520
521         status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
522         if (ACPI_FAILURE(status)) {
523                 if (status != AE_NOT_FOUND) {
524                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
525                 }
526                 return -ENODEV;
527         }
528
529         tsd = buffer.pointer;
530         if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
531                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _TSD data\n"));
532                 result = -EFAULT;
533                 goto end;
534         }
535
536         if (tsd->package.count != 1) {
537                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _TSD data\n"));
538                 result = -EFAULT;
539                 goto end;
540         }
541
542         pdomain = &(pr->throttling.domain_info);
543
544         state.length = sizeof(struct acpi_tsd_package);
545         state.pointer = pdomain;
546
547         status = acpi_extract_package(&(tsd->package.elements[0]),
548                                       &format, &state);
549         if (ACPI_FAILURE(status)) {
550                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _TSD data\n"));
551                 result = -EFAULT;
552                 goto end;
553         }
554
555         if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
556                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _TSD:num_entries\n"));
557                 result = -EFAULT;
558                 goto end;
559         }
560
561         if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
562                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _TSD:revision\n"));
563                 result = -EFAULT;
564                 goto end;
565         }
566
567         pthrottling = &pr->throttling;
568         pthrottling->tsd_valid_flag = 1;
569         pthrottling->shared_type = pdomain->coord_type;
570         cpu_set(pr->id, pthrottling->shared_cpu_map);
571         /*
572          * If the coordination type is not defined in ACPI spec,
573          * the tsd_valid_flag will be clear and coordination type
574          * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
575          */
576         if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
577                 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
578                 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
579                 pthrottling->tsd_valid_flag = 0;
580                 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
581         }
582
583       end:
584         kfree(buffer.pointer);
585         return result;
586 }
587
588 /* --------------------------------------------------------------------------
589                               Throttling Control
590    -------------------------------------------------------------------------- */
591 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
592 {
593         int state = 0;
594         u32 value = 0;
595         u32 duty_mask = 0;
596         u32 duty_value = 0;
597
598         if (!pr)
599                 return -EINVAL;
600
601         if (!pr->flags.throttling)
602                 return -ENODEV;
603
604         pr->throttling.state = 0;
605
606         duty_mask = pr->throttling.state_count - 1;
607
608         duty_mask <<= pr->throttling.duty_offset;
609
610         local_irq_disable();
611
612         value = inl(pr->throttling.address);
613
614         /*
615          * Compute the current throttling state when throttling is enabled
616          * (bit 4 is on).
617          */
618         if (value & 0x10) {
619                 duty_value = value & duty_mask;
620                 duty_value >>= pr->throttling.duty_offset;
621
622                 if (duty_value)
623                         state = pr->throttling.state_count - duty_value;
624         }
625
626         pr->throttling.state = state;
627
628         local_irq_enable();
629
630         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
631                           "Throttling state is T%d (%d%% throttling applied)\n",
632                           state, pr->throttling.states[state].performance));
633
634         return 0;
635 }
636
637 #ifdef CONFIG_X86
638 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
639                                         acpi_integer * value)
640 {
641         struct cpuinfo_x86 *c;
642         u64 msr_high, msr_low;
643         unsigned int cpu;
644         u64 msr = 0;
645         int ret = -1;
646
647         cpu = pr->id;
648         c = &cpu_data(cpu);
649
650         if ((c->x86_vendor != X86_VENDOR_INTEL) ||
651                 !cpu_has(c, X86_FEATURE_ACPI)) {
652                 printk(KERN_ERR PREFIX
653                         "HARDWARE addr space,NOT supported yet\n");
654         } else {
655                 msr_low = 0;
656                 msr_high = 0;
657                 rdmsr_safe(MSR_IA32_THERM_CONTROL,
658                         (u32 *)&msr_low , (u32 *) &msr_high);
659                 msr = (msr_high << 32) | msr_low;
660                 *value = (acpi_integer) msr;
661                 ret = 0;
662         }
663         return ret;
664 }
665
666 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
667 {
668         struct cpuinfo_x86 *c;
669         unsigned int cpu;
670         int ret = -1;
671         u64 msr;
672
673         cpu = pr->id;
674         c = &cpu_data(cpu);
675
676         if ((c->x86_vendor != X86_VENDOR_INTEL) ||
677                 !cpu_has(c, X86_FEATURE_ACPI)) {
678                 printk(KERN_ERR PREFIX
679                         "HARDWARE addr space,NOT supported yet\n");
680         } else {
681                 msr = value;
682                 wrmsr_safe(MSR_IA32_THERM_CONTROL,
683                         msr & 0xffffffff, msr >> 32);
684                 ret = 0;
685         }
686         return ret;
687 }
688 #else
689 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
690                                 acpi_integer * value)
691 {
692         printk(KERN_ERR PREFIX
693                 "HARDWARE addr space,NOT supported yet\n");
694         return -1;
695 }
696
697 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
698 {
699         printk(KERN_ERR PREFIX
700                 "HARDWARE addr space,NOT supported yet\n");
701         return -1;
702 }
703 #endif
704
705 static int acpi_read_throttling_status(struct acpi_processor *pr,
706                                         acpi_integer *value)
707 {
708         u32 bit_width, bit_offset;
709         u64 ptc_value;
710         u64 ptc_mask;
711         struct acpi_processor_throttling *throttling;
712         int ret = -1;
713
714         throttling = &pr->throttling;
715         switch (throttling->status_register.space_id) {
716         case ACPI_ADR_SPACE_SYSTEM_IO:
717                 ptc_value = 0;
718                 bit_width = throttling->status_register.bit_width;
719                 bit_offset = throttling->status_register.bit_offset;
720
721                 acpi_os_read_port((acpi_io_address) throttling->status_register.
722                                   address, (u32 *) &ptc_value,
723                                   (u32) (bit_width + bit_offset));
724                 ptc_mask = (1 << bit_width) - 1;
725                 *value = (acpi_integer) ((ptc_value >> bit_offset) & ptc_mask);
726                 ret = 0;
727                 break;
728         case ACPI_ADR_SPACE_FIXED_HARDWARE:
729                 ret = acpi_throttling_rdmsr(pr, value);
730                 break;
731         default:
732                 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
733                        (u32) (throttling->status_register.space_id));
734         }
735         return ret;
736 }
737
738 static int acpi_write_throttling_state(struct acpi_processor *pr,
739                                 acpi_integer value)
740 {
741         u32 bit_width, bit_offset;
742         u64 ptc_value;
743         u64 ptc_mask;
744         struct acpi_processor_throttling *throttling;
745         int ret = -1;
746
747         throttling = &pr->throttling;
748         switch (throttling->control_register.space_id) {
749         case ACPI_ADR_SPACE_SYSTEM_IO:
750                 bit_width = throttling->control_register.bit_width;
751                 bit_offset = throttling->control_register.bit_offset;
752                 ptc_mask = (1 << bit_width) - 1;
753                 ptc_value = value & ptc_mask;
754
755                 acpi_os_write_port((acpi_io_address) throttling->
756                                         control_register.address,
757                                         (u32) (ptc_value << bit_offset),
758                                         (u32) (bit_width + bit_offset));
759                 ret = 0;
760                 break;
761         case ACPI_ADR_SPACE_FIXED_HARDWARE:
762                 ret = acpi_throttling_wrmsr(pr, value);
763                 break;
764         default:
765                 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
766                        (u32) (throttling->control_register.space_id));
767         }
768         return ret;
769 }
770
771 static int acpi_get_throttling_state(struct acpi_processor *pr,
772                                 acpi_integer value)
773 {
774         int i;
775
776         for (i = 0; i < pr->throttling.state_count; i++) {
777                 struct acpi_processor_tx_tss *tx =
778                     (struct acpi_processor_tx_tss *)&(pr->throttling.
779                                                       states_tss[i]);
780                 if (tx->control == value)
781                         break;
782         }
783         if (i > pr->throttling.state_count)
784                 i = -1;
785         return i;
786 }
787
788 static int acpi_get_throttling_value(struct acpi_processor *pr,
789                         int state, acpi_integer *value)
790 {
791         int ret = -1;
792
793         if (state >= 0 && state <= pr->throttling.state_count) {
794                 struct acpi_processor_tx_tss *tx =
795                     (struct acpi_processor_tx_tss *)&(pr->throttling.
796                                                       states_tss[state]);
797                 *value = tx->control;
798                 ret = 0;
799         }
800         return ret;
801 }
802
803 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
804 {
805         int state = 0;
806         int ret;
807         acpi_integer value;
808
809         if (!pr)
810                 return -EINVAL;
811
812         if (!pr->flags.throttling)
813                 return -ENODEV;
814
815         pr->throttling.state = 0;
816
817         value = 0;
818         ret = acpi_read_throttling_status(pr, &value);
819         if (ret >= 0) {
820                 state = acpi_get_throttling_state(pr, value);
821                 pr->throttling.state = state;
822         }
823
824         return 0;
825 }
826
827 static int acpi_processor_get_throttling(struct acpi_processor *pr)
828 {
829         cpumask_t saved_mask;
830         int ret;
831
832         if (!pr)
833                 return -EINVAL;
834
835         if (!pr->flags.throttling)
836                 return -ENODEV;
837         /*
838          * Migrate task to the cpu pointed by pr.
839          */
840         saved_mask = current->cpus_allowed;
841         set_cpus_allowed_ptr(current, &cpumask_of_cpu(pr->id));
842         ret = pr->throttling.acpi_processor_get_throttling(pr);
843         /* restore the previous state */
844         set_cpus_allowed_ptr(current, &saved_mask);
845
846         return ret;
847 }
848
849 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
850 {
851         int i, step;
852
853         if (!pr->throttling.address) {
854                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
855                 return -EINVAL;
856         } else if (!pr->throttling.duty_width) {
857                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
858                 return -EINVAL;
859         }
860         /* TBD: Support duty_cycle values that span bit 4. */
861         else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
862                 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
863                 return -EINVAL;
864         }
865
866         pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
867
868         /*
869          * Compute state values. Note that throttling displays a linear power
870          * performance relationship (at 50% performance the CPU will consume
871          * 50% power).  Values are in 1/10th of a percent to preserve accuracy.
872          */
873
874         step = (1000 / pr->throttling.state_count);
875
876         for (i = 0; i < pr->throttling.state_count; i++) {
877                 pr->throttling.states[i].performance = 1000 - step * i;
878                 pr->throttling.states[i].power = 1000 - step * i;
879         }
880         return 0;
881 }
882
883 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
884                                               int state)
885 {
886         u32 value = 0;
887         u32 duty_mask = 0;
888         u32 duty_value = 0;
889
890         if (!pr)
891                 return -EINVAL;
892
893         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
894                 return -EINVAL;
895
896         if (!pr->flags.throttling)
897                 return -ENODEV;
898
899         if (state == pr->throttling.state)
900                 return 0;
901
902         if (state < pr->throttling_platform_limit)
903                 return -EPERM;
904         /*
905          * Calculate the duty_value and duty_mask.
906          */
907         if (state) {
908                 duty_value = pr->throttling.state_count - state;
909
910                 duty_value <<= pr->throttling.duty_offset;
911
912                 /* Used to clear all duty_value bits */
913                 duty_mask = pr->throttling.state_count - 1;
914
915                 duty_mask <<= acpi_gbl_FADT.duty_offset;
916                 duty_mask = ~duty_mask;
917         }
918
919         local_irq_disable();
920
921         /*
922          * Disable throttling by writing a 0 to bit 4.  Note that we must
923          * turn it off before you can change the duty_value.
924          */
925         value = inl(pr->throttling.address);
926         if (value & 0x10) {
927                 value &= 0xFFFFFFEF;
928                 outl(value, pr->throttling.address);
929         }
930
931         /*
932          * Write the new duty_value and then enable throttling.  Note
933          * that a state value of 0 leaves throttling disabled.
934          */
935         if (state) {
936                 value &= duty_mask;
937                 value |= duty_value;
938                 outl(value, pr->throttling.address);
939
940                 value |= 0x00000010;
941                 outl(value, pr->throttling.address);
942         }
943
944         pr->throttling.state = state;
945
946         local_irq_enable();
947
948         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
949                           "Throttling state set to T%d (%d%%)\n", state,
950                           (pr->throttling.states[state].performance ? pr->
951                            throttling.states[state].performance / 10 : 0)));
952
953         return 0;
954 }
955
956 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
957                                              int state)
958 {
959         int ret;
960         acpi_integer value;
961
962         if (!pr)
963                 return -EINVAL;
964
965         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
966                 return -EINVAL;
967
968         if (!pr->flags.throttling)
969                 return -ENODEV;
970
971         if (state == pr->throttling.state)
972                 return 0;
973
974         if (state < pr->throttling_platform_limit)
975                 return -EPERM;
976
977         value = 0;
978         ret = acpi_get_throttling_value(pr, state, &value);
979         if (ret >= 0) {
980                 acpi_write_throttling_state(pr, value);
981                 pr->throttling.state = state;
982         }
983
984         return 0;
985 }
986
987 int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
988 {
989         cpumask_t saved_mask;
990         int ret = 0;
991         unsigned int i;
992         struct acpi_processor *match_pr;
993         struct acpi_processor_throttling *p_throttling;
994         struct throttling_tstate t_state;
995         cpumask_t online_throttling_cpus;
996
997         if (!pr)
998                 return -EINVAL;
999
1000         if (!pr->flags.throttling)
1001                 return -ENODEV;
1002
1003         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1004                 return -EINVAL;
1005
1006         saved_mask = current->cpus_allowed;
1007         t_state.target_state = state;
1008         p_throttling = &(pr->throttling);
1009         cpus_and(online_throttling_cpus, cpu_online_map,
1010                         p_throttling->shared_cpu_map);
1011         /*
1012          * The throttling notifier will be called for every
1013          * affected cpu in order to get one proper T-state.
1014          * The notifier event is THROTTLING_PRECHANGE.
1015          */
1016         for_each_cpu_mask(i, online_throttling_cpus) {
1017                 t_state.cpu = i;
1018                 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1019                                                         &t_state);
1020         }
1021         /*
1022          * The function of acpi_processor_set_throttling will be called
1023          * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1024          * it is necessary to call it for every affected cpu. Otherwise
1025          * it can be called only for the cpu pointed by pr.
1026          */
1027         if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1028                 set_cpus_allowed_ptr(current, &cpumask_of_cpu(pr->id));
1029                 ret = p_throttling->acpi_processor_set_throttling(pr,
1030                                                 t_state.target_state);
1031         } else {
1032                 /*
1033                  * When the T-state coordination is SW_ALL or HW_ALL,
1034                  * it is necessary to set T-state for every affected
1035                  * cpus.
1036                  */
1037                 for_each_cpu_mask(i, online_throttling_cpus) {
1038                         match_pr = processors[i];
1039                         /*
1040                          * If the pointer is invalid, we will report the
1041                          * error message and continue.
1042                          */
1043                         if (!match_pr) {
1044                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1045                                         "Invalid Pointer for CPU %d\n", i));
1046                                 continue;
1047                         }
1048                         /*
1049                          * If the throttling control is unsupported on CPU i,
1050                          * we will report the error message and continue.
1051                          */
1052                         if (!match_pr->flags.throttling) {
1053                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1054                                         "Throttling Controll is unsupported "
1055                                         "on CPU %d\n", i));
1056                                 continue;
1057                         }
1058                         t_state.cpu = i;
1059                         set_cpus_allowed_ptr(current, &cpumask_of_cpu(i));
1060                         ret = match_pr->throttling.
1061                                 acpi_processor_set_throttling(
1062                                 match_pr, t_state.target_state);
1063                 }
1064         }
1065         /*
1066          * After the set_throttling is called, the
1067          * throttling notifier is called for every
1068          * affected cpu to update the T-states.
1069          * The notifier event is THROTTLING_POSTCHANGE
1070          */
1071         for_each_cpu_mask(i, online_throttling_cpus) {
1072                 t_state.cpu = i;
1073                 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1074                                                         &t_state);
1075         }
1076         /* restore the previous state */
1077         set_cpus_allowed_ptr(current, &saved_mask);
1078         return ret;
1079 }
1080
1081 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1082 {
1083         int result = 0;
1084         struct acpi_processor_throttling *pthrottling;
1085
1086         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1087                           "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1088                           pr->throttling.address,
1089                           pr->throttling.duty_offset,
1090                           pr->throttling.duty_width));
1091
1092         if (!pr)
1093                 return -EINVAL;
1094
1095         /*
1096          * Evaluate _PTC, _TSS and _TPC
1097          * They must all be present or none of them can be used.
1098          */
1099         if (acpi_processor_get_throttling_control(pr) ||
1100                 acpi_processor_get_throttling_states(pr) ||
1101                 acpi_processor_get_platform_limit(pr))
1102         {
1103                 pr->throttling.acpi_processor_get_throttling =
1104                     &acpi_processor_get_throttling_fadt;
1105                 pr->throttling.acpi_processor_set_throttling =
1106                     &acpi_processor_set_throttling_fadt;
1107                 if (acpi_processor_get_fadt_info(pr))
1108                         return 0;
1109         } else {
1110                 pr->throttling.acpi_processor_get_throttling =
1111                     &acpi_processor_get_throttling_ptc;
1112                 pr->throttling.acpi_processor_set_throttling =
1113                     &acpi_processor_set_throttling_ptc;
1114         }
1115
1116         /*
1117          * If TSD package for one CPU can't be parsed successfully, it means
1118          * that this CPU will have no coordination with other CPUs.
1119          */
1120         if (acpi_processor_get_tsd(pr)) {
1121                 pthrottling = &pr->throttling;
1122                 pthrottling->tsd_valid_flag = 0;
1123                 cpu_set(pr->id, pthrottling->shared_cpu_map);
1124                 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1125         }
1126
1127         /*
1128          * PIIX4 Errata: We don't support throttling on the original PIIX4.
1129          * This shouldn't be an issue as few (if any) mobile systems ever
1130          * used this part.
1131          */
1132         if (errata.piix4.throttle) {
1133                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1134                                   "Throttling not supported on PIIX4 A- or B-step\n"));
1135                 return 0;
1136         }
1137
1138         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1139                           pr->throttling.state_count));
1140
1141         pr->flags.throttling = 1;
1142
1143         /*
1144          * Disable throttling (if enabled).  We'll let subsequent policy (e.g.
1145          * thermal) decide to lower performance if it so chooses, but for now
1146          * we'll crank up the speed.
1147          */
1148
1149         result = acpi_processor_get_throttling(pr);
1150         if (result)
1151                 goto end;
1152
1153         if (pr->throttling.state) {
1154                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1155                                   "Disabling throttling (was T%d)\n",
1156                                   pr->throttling.state));
1157                 result = acpi_processor_set_throttling(pr, 0);
1158                 if (result)
1159                         goto end;
1160         }
1161
1162       end:
1163         if (result)
1164                 pr->flags.throttling = 0;
1165
1166         return result;
1167 }
1168
1169 /* proc interface */
1170
1171 static int acpi_processor_throttling_seq_show(struct seq_file *seq,
1172                                               void *offset)
1173 {
1174         struct acpi_processor *pr = seq->private;
1175         int i = 0;
1176         int result = 0;
1177
1178         if (!pr)
1179                 goto end;
1180
1181         if (!(pr->throttling.state_count > 0)) {
1182                 seq_puts(seq, "<not supported>\n");
1183                 goto end;
1184         }
1185
1186         result = acpi_processor_get_throttling(pr);
1187
1188         if (result) {
1189                 seq_puts(seq,
1190                          "Could not determine current throttling state.\n");
1191                 goto end;
1192         }
1193
1194         seq_printf(seq, "state count:             %d\n"
1195                    "active state:            T%d\n"
1196                    "state available: T%d to T%d\n",
1197                    pr->throttling.state_count, pr->throttling.state,
1198                    pr->throttling_platform_limit,
1199                    pr->throttling.state_count - 1);
1200
1201         seq_puts(seq, "states:\n");
1202         if (pr->throttling.acpi_processor_get_throttling ==
1203                         acpi_processor_get_throttling_fadt) {
1204                 for (i = 0; i < pr->throttling.state_count; i++)
1205                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1206                                    (i == pr->throttling.state ? '*' : ' '), i,
1207                                    (pr->throttling.states[i].performance ? pr->
1208                                     throttling.states[i].performance / 10 : 0));
1209         } else {
1210                 for (i = 0; i < pr->throttling.state_count; i++)
1211                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1212                                    (i == pr->throttling.state ? '*' : ' '), i,
1213                                    (int)pr->throttling.states_tss[i].
1214                                    freqpercentage);
1215         }
1216
1217       end:
1218         return 0;
1219 }
1220
1221 static int acpi_processor_throttling_open_fs(struct inode *inode,
1222                                              struct file *file)
1223 {
1224         return single_open(file, acpi_processor_throttling_seq_show,
1225                            PDE(inode)->data);
1226 }
1227
1228 static ssize_t acpi_processor_write_throttling(struct file *file,
1229                                                const char __user * buffer,
1230                                                size_t count, loff_t * data)
1231 {
1232         int result = 0;
1233         struct seq_file *m = file->private_data;
1234         struct acpi_processor *pr = m->private;
1235         char state_string[12] = { '\0' };
1236
1237         if (!pr || (count > sizeof(state_string) - 1))
1238                 return -EINVAL;
1239
1240         if (copy_from_user(state_string, buffer, count))
1241                 return -EFAULT;
1242
1243         state_string[count] = '\0';
1244
1245         result = acpi_processor_set_throttling(pr,
1246                                                simple_strtoul(state_string,
1247                                                               NULL, 0));
1248         if (result)
1249                 return result;
1250
1251         return count;
1252 }
1253
1254 struct file_operations acpi_processor_throttling_fops = {
1255         .owner = THIS_MODULE,
1256         .open = acpi_processor_throttling_open_fs,
1257         .read = seq_read,
1258         .write = acpi_processor_write_throttling,
1259         .llseek = seq_lseek,
1260         .release = single_release,
1261 };