p54: prepare the eeprom parser routines for longbow
[linux-2.6] / drivers / acpi / processor_throttling.c
1 /*
2  * processor_throttling.c - Throttling submodule of the ACPI processor driver
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *  Copyright (C) 2004       Dominik Brodowski <linux@brodo.de>
7  *  Copyright (C) 2004  Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8  *                      - Added processor hotplug support
9  *
10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11  *
12  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2 of the License, or (at
15  *  your option) any later version.
16  *
17  *  This program is distributed in the hope that it will be useful, but
18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20  *  General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License along
23  *  with this program; if not, write to the Free Software Foundation, Inc.,
24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25  *
26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27  */
28
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/sched.h>
33 #include <linux/cpufreq.h>
34 #include <linux/proc_fs.h>
35 #include <linux/seq_file.h>
36
37 #include <asm/io.h>
38 #include <asm/uaccess.h>
39
40 #include <acpi/acpi_bus.h>
41 #include <acpi/acpi_drivers.h>
42 #include <acpi/processor.h>
43
44 #define ACPI_PROCESSOR_CLASS            "processor"
45 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
46 ACPI_MODULE_NAME("processor_throttling");
47
48 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_var_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         if (!alloc_cpumask_var(&covered_cpus, GFP_KERNEL))
70                 return -ENOMEM;
71
72         /*
73          * Now that we have _TSD data from all CPUs, lets setup T-state
74          * coordination between all CPUs.
75          */
76         for_each_possible_cpu(i) {
77                 pr = per_cpu(processors, i);
78                 if (!pr)
79                         continue;
80
81                 /* Basic validity check for domain info */
82                 pthrottling = &(pr->throttling);
83
84                 /*
85                  * If tsd package for one cpu is invalid, the coordination
86                  * among all CPUs is thought as invalid.
87                  * Maybe it is ugly.
88                  */
89                 if (!pthrottling->tsd_valid_flag) {
90                         retval = -EINVAL;
91                         break;
92                 }
93         }
94         if (retval)
95                 goto err_ret;
96
97         cpumask_clear(covered_cpus);
98         for_each_possible_cpu(i) {
99                 pr = per_cpu(processors, i);
100                 if (!pr)
101                         continue;
102
103                 if (cpumask_test_cpu(i, covered_cpus))
104                         continue;
105                 pthrottling = &pr->throttling;
106
107                 pdomain = &(pthrottling->domain_info);
108                 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
109                 cpumask_set_cpu(i, covered_cpus);
110                 /*
111                  * If the number of processor in the TSD domain is 1, it is
112                  * unnecessary to parse the coordination for this CPU.
113                  */
114                 if (pdomain->num_processors <= 1)
115                         continue;
116
117                 /* Validate the Domain info */
118                 count_target = pdomain->num_processors;
119                 count = 1;
120
121                 for_each_possible_cpu(j) {
122                         if (i == j)
123                                 continue;
124
125                         match_pr = per_cpu(processors, j);
126                         if (!match_pr)
127                                 continue;
128
129                         match_pthrottling = &(match_pr->throttling);
130                         match_pdomain = &(match_pthrottling->domain_info);
131                         if (match_pdomain->domain != pdomain->domain)
132                                 continue;
133
134                         /* Here i and j are in the same domain.
135                          * If two TSD packages have the same domain, they
136                          * should have the same num_porcessors and
137                          * coordination type. Otherwise it will be regarded
138                          * as illegal.
139                          */
140                         if (match_pdomain->num_processors != count_target) {
141                                 retval = -EINVAL;
142                                 goto err_ret;
143                         }
144
145                         if (pdomain->coord_type != match_pdomain->coord_type) {
146                                 retval = -EINVAL;
147                                 goto err_ret;
148                         }
149
150                         cpumask_set_cpu(j, covered_cpus);
151                         cpumask_set_cpu(j, pthrottling->shared_cpu_map);
152                         count++;
153                 }
154                 for_each_possible_cpu(j) {
155                         if (i == j)
156                                 continue;
157
158                         match_pr = per_cpu(processors, j);
159                         if (!match_pr)
160                                 continue;
161
162                         match_pthrottling = &(match_pr->throttling);
163                         match_pdomain = &(match_pthrottling->domain_info);
164                         if (match_pdomain->domain != pdomain->domain)
165                                 continue;
166
167                         /*
168                          * If some CPUS have the same domain, they
169                          * will have the same shared_cpu_map.
170                          */
171                         cpumask_copy(match_pthrottling->shared_cpu_map,
172                                      pthrottling->shared_cpu_map);
173                 }
174         }
175
176 err_ret:
177         free_cpumask_var(covered_cpus);
178
179         for_each_possible_cpu(i) {
180                 pr = per_cpu(processors, i);
181                 if (!pr)
182                         continue;
183
184                 /*
185                  * Assume no coordination on any error parsing domain info.
186                  * The coordination type will be forced as SW_ALL.
187                  */
188                 if (retval) {
189                         pthrottling = &(pr->throttling);
190                         cpumask_clear(pthrottling->shared_cpu_map);
191                         cpumask_set_cpu(i, pthrottling->shared_cpu_map);
192                         pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
193                 }
194         }
195
196         return retval;
197 }
198
199 /*
200  * Update the T-state coordination after the _TSD
201  * data for all cpus is obtained.
202  */
203 void acpi_processor_throttling_init(void)
204 {
205         if (acpi_processor_update_tsd_coord())
206                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
207                         "Assume no T-state coordination\n"));
208
209         return;
210 }
211
212 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
213 {
214         struct throttling_tstate *p_tstate = data;
215         struct acpi_processor *pr;
216         unsigned int cpu ;
217         int target_state;
218         struct acpi_processor_limit *p_limit;
219         struct acpi_processor_throttling *p_throttling;
220
221         cpu = p_tstate->cpu;
222         pr = per_cpu(processors, cpu);
223         if (!pr) {
224                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
225                 return 0;
226         }
227         if (!pr->flags.throttling) {
228                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
229                                 "unsupported on CPU %d\n", cpu));
230                 return 0;
231         }
232         target_state = p_tstate->target_state;
233         p_throttling = &(pr->throttling);
234         switch (event) {
235         case THROTTLING_PRECHANGE:
236                 /*
237                  * Prechange event is used to choose one proper t-state,
238                  * which meets the limits of thermal, user and _TPC.
239                  */
240                 p_limit = &pr->limit;
241                 if (p_limit->thermal.tx > target_state)
242                         target_state = p_limit->thermal.tx;
243                 if (p_limit->user.tx > target_state)
244                         target_state = p_limit->user.tx;
245                 if (pr->throttling_platform_limit > target_state)
246                         target_state = pr->throttling_platform_limit;
247                 if (target_state >= p_throttling->state_count) {
248                         printk(KERN_WARNING
249                                 "Exceed the limit of T-state \n");
250                         target_state = p_throttling->state_count - 1;
251                 }
252                 p_tstate->target_state = target_state;
253                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
254                                 "target T-state of CPU %d is T%d\n",
255                                 cpu, target_state));
256                 break;
257         case THROTTLING_POSTCHANGE:
258                 /*
259                  * Postchange event is only used to update the
260                  * T-state flag of acpi_processor_throttling.
261                  */
262                 p_throttling->state = target_state;
263                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
264                                 "CPU %d is switched to T%d\n",
265                                 cpu, target_state));
266                 break;
267         default:
268                 printk(KERN_WARNING
269                         "Unsupported Throttling notifier event\n");
270                 break;
271         }
272
273         return 0;
274 }
275
276 /*
277  * _TPC - Throttling Present Capabilities
278  */
279 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
280 {
281         acpi_status status = 0;
282         unsigned long long tpc = 0;
283
284         if (!pr)
285                 return -EINVAL;
286         status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
287         if (ACPI_FAILURE(status)) {
288                 if (status != AE_NOT_FOUND) {
289                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
290                 }
291                 return -ENODEV;
292         }
293         pr->throttling_platform_limit = (int)tpc;
294         return 0;
295 }
296
297 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
298 {
299         int result = 0;
300         int throttling_limit;
301         int current_state;
302         struct acpi_processor_limit *limit;
303         int target_state;
304
305         result = acpi_processor_get_platform_limit(pr);
306         if (result) {
307                 /* Throttling Limit is unsupported */
308                 return result;
309         }
310
311         throttling_limit = pr->throttling_platform_limit;
312         if (throttling_limit >= pr->throttling.state_count) {
313                 /* Uncorrect Throttling Limit */
314                 return -EINVAL;
315         }
316
317         current_state = pr->throttling.state;
318         if (current_state > throttling_limit) {
319                 /*
320                  * The current state can meet the requirement of
321                  * _TPC limit. But it is reasonable that OSPM changes
322                  * t-states from high to low for better performance.
323                  * Of course the limit condition of thermal
324                  * and user should be considered.
325                  */
326                 limit = &pr->limit;
327                 target_state = throttling_limit;
328                 if (limit->thermal.tx > target_state)
329                         target_state = limit->thermal.tx;
330                 if (limit->user.tx > target_state)
331                         target_state = limit->user.tx;
332         } else if (current_state == throttling_limit) {
333                 /*
334                  * Unnecessary to change the throttling state
335                  */
336                 return 0;
337         } else {
338                 /*
339                  * If the current state is lower than the limit of _TPC, it
340                  * will be forced to switch to the throttling state defined
341                  * by throttling_platfor_limit.
342                  * Because the previous state meets with the limit condition
343                  * of thermal and user, it is unnecessary to check it again.
344                  */
345                 target_state = throttling_limit;
346         }
347         return acpi_processor_set_throttling(pr, target_state);
348 }
349
350 /*
351  * _PTC - Processor Throttling Control (and status) register location
352  */
353 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
354 {
355         int result = 0;
356         acpi_status status = 0;
357         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
358         union acpi_object *ptc = NULL;
359         union acpi_object obj = { 0 };
360         struct acpi_processor_throttling *throttling;
361
362         status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
363         if (ACPI_FAILURE(status)) {
364                 if (status != AE_NOT_FOUND) {
365                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
366                 }
367                 return -ENODEV;
368         }
369
370         ptc = (union acpi_object *)buffer.pointer;
371         if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
372             || (ptc->package.count != 2)) {
373                 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
374                 result = -EFAULT;
375                 goto end;
376         }
377
378         /*
379          * control_register
380          */
381
382         obj = ptc->package.elements[0];
383
384         if ((obj.type != ACPI_TYPE_BUFFER)
385             || (obj.buffer.length < sizeof(struct acpi_ptc_register))
386             || (obj.buffer.pointer == NULL)) {
387                 printk(KERN_ERR PREFIX
388                        "Invalid _PTC data (control_register)\n");
389                 result = -EFAULT;
390                 goto end;
391         }
392         memcpy(&pr->throttling.control_register, obj.buffer.pointer,
393                sizeof(struct acpi_ptc_register));
394
395         /*
396          * status_register
397          */
398
399         obj = ptc->package.elements[1];
400
401         if ((obj.type != ACPI_TYPE_BUFFER)
402             || (obj.buffer.length < sizeof(struct acpi_ptc_register))
403             || (obj.buffer.pointer == NULL)) {
404                 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
405                 result = -EFAULT;
406                 goto end;
407         }
408
409         memcpy(&pr->throttling.status_register, obj.buffer.pointer,
410                sizeof(struct acpi_ptc_register));
411
412         throttling = &pr->throttling;
413
414         if ((throttling->control_register.bit_width +
415                 throttling->control_register.bit_offset) > 32) {
416                 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
417                 result = -EFAULT;
418                 goto end;
419         }
420
421         if ((throttling->status_register.bit_width +
422                 throttling->status_register.bit_offset) > 32) {
423                 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
424                 result = -EFAULT;
425                 goto end;
426         }
427
428       end:
429         kfree(buffer.pointer);
430
431         return result;
432 }
433
434 /*
435  * _TSS - Throttling Supported States
436  */
437 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
438 {
439         int result = 0;
440         acpi_status status = AE_OK;
441         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
442         struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
443         struct acpi_buffer state = { 0, NULL };
444         union acpi_object *tss = NULL;
445         int i;
446
447         status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
448         if (ACPI_FAILURE(status)) {
449                 if (status != AE_NOT_FOUND) {
450                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
451                 }
452                 return -ENODEV;
453         }
454
455         tss = buffer.pointer;
456         if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
457                 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
458                 result = -EFAULT;
459                 goto end;
460         }
461
462         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
463                           tss->package.count));
464
465         pr->throttling.state_count = tss->package.count;
466         pr->throttling.states_tss =
467             kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
468                     GFP_KERNEL);
469         if (!pr->throttling.states_tss) {
470                 result = -ENOMEM;
471                 goto end;
472         }
473
474         for (i = 0; i < pr->throttling.state_count; i++) {
475
476                 struct acpi_processor_tx_tss *tx =
477                     (struct acpi_processor_tx_tss *)&(pr->throttling.
478                                                       states_tss[i]);
479
480                 state.length = sizeof(struct acpi_processor_tx_tss);
481                 state.pointer = tx;
482
483                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
484
485                 status = acpi_extract_package(&(tss->package.elements[i]),
486                                               &format, &state);
487                 if (ACPI_FAILURE(status)) {
488                         ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
489                         result = -EFAULT;
490                         kfree(pr->throttling.states_tss);
491                         goto end;
492                 }
493
494                 if (!tx->freqpercentage) {
495                         printk(KERN_ERR PREFIX
496                                "Invalid _TSS data: freq is zero\n");
497                         result = -EFAULT;
498                         kfree(pr->throttling.states_tss);
499                         goto end;
500                 }
501         }
502
503       end:
504         kfree(buffer.pointer);
505
506         return result;
507 }
508
509 /*
510  * _TSD - T-State Dependencies
511  */
512 static int acpi_processor_get_tsd(struct acpi_processor *pr)
513 {
514         int result = 0;
515         acpi_status status = AE_OK;
516         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
517         struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
518         struct acpi_buffer state = { 0, NULL };
519         union acpi_object *tsd = NULL;
520         struct acpi_tsd_package *pdomain;
521         struct acpi_processor_throttling *pthrottling;
522
523         pthrottling = &pr->throttling;
524         pthrottling->tsd_valid_flag = 0;
525
526         status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
527         if (ACPI_FAILURE(status)) {
528                 if (status != AE_NOT_FOUND) {
529                         ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
530                 }
531                 return -ENODEV;
532         }
533
534         tsd = buffer.pointer;
535         if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
536                 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
537                 result = -EFAULT;
538                 goto end;
539         }
540
541         if (tsd->package.count != 1) {
542                 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
543                 result = -EFAULT;
544                 goto end;
545         }
546
547         pdomain = &(pr->throttling.domain_info);
548
549         state.length = sizeof(struct acpi_tsd_package);
550         state.pointer = pdomain;
551
552         status = acpi_extract_package(&(tsd->package.elements[0]),
553                                       &format, &state);
554         if (ACPI_FAILURE(status)) {
555                 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
556                 result = -EFAULT;
557                 goto end;
558         }
559
560         if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
561                 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
562                 result = -EFAULT;
563                 goto end;
564         }
565
566         if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
567                 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
568                 result = -EFAULT;
569                 goto end;
570         }
571
572         pthrottling = &pr->throttling;
573         pthrottling->tsd_valid_flag = 1;
574         pthrottling->shared_type = pdomain->coord_type;
575         cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
576         /*
577          * If the coordination type is not defined in ACPI spec,
578          * the tsd_valid_flag will be clear and coordination type
579          * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
580          */
581         if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
582                 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
583                 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
584                 pthrottling->tsd_valid_flag = 0;
585                 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
586         }
587
588       end:
589         kfree(buffer.pointer);
590         return result;
591 }
592
593 /* --------------------------------------------------------------------------
594                               Throttling Control
595    -------------------------------------------------------------------------- */
596 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
597 {
598         int state = 0;
599         u32 value = 0;
600         u32 duty_mask = 0;
601         u32 duty_value = 0;
602
603         if (!pr)
604                 return -EINVAL;
605
606         if (!pr->flags.throttling)
607                 return -ENODEV;
608
609         pr->throttling.state = 0;
610
611         duty_mask = pr->throttling.state_count - 1;
612
613         duty_mask <<= pr->throttling.duty_offset;
614
615         local_irq_disable();
616
617         value = inl(pr->throttling.address);
618
619         /*
620          * Compute the current throttling state when throttling is enabled
621          * (bit 4 is on).
622          */
623         if (value & 0x10) {
624                 duty_value = value & duty_mask;
625                 duty_value >>= pr->throttling.duty_offset;
626
627                 if (duty_value)
628                         state = pr->throttling.state_count - duty_value;
629         }
630
631         pr->throttling.state = state;
632
633         local_irq_enable();
634
635         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
636                           "Throttling state is T%d (%d%% throttling applied)\n",
637                           state, pr->throttling.states[state].performance));
638
639         return 0;
640 }
641
642 #ifdef CONFIG_X86
643 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
644                                         acpi_integer * value)
645 {
646         struct cpuinfo_x86 *c;
647         u64 msr_high, msr_low;
648         unsigned int cpu;
649         u64 msr = 0;
650         int ret = -1;
651
652         cpu = pr->id;
653         c = &cpu_data(cpu);
654
655         if ((c->x86_vendor != X86_VENDOR_INTEL) ||
656                 !cpu_has(c, X86_FEATURE_ACPI)) {
657                 printk(KERN_ERR PREFIX
658                         "HARDWARE addr space,NOT supported yet\n");
659         } else {
660                 msr_low = 0;
661                 msr_high = 0;
662                 rdmsr_safe(MSR_IA32_THERM_CONTROL,
663                         (u32 *)&msr_low , (u32 *) &msr_high);
664                 msr = (msr_high << 32) | msr_low;
665                 *value = (acpi_integer) msr;
666                 ret = 0;
667         }
668         return ret;
669 }
670
671 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
672 {
673         struct cpuinfo_x86 *c;
674         unsigned int cpu;
675         int ret = -1;
676         u64 msr;
677
678         cpu = pr->id;
679         c = &cpu_data(cpu);
680
681         if ((c->x86_vendor != X86_VENDOR_INTEL) ||
682                 !cpu_has(c, X86_FEATURE_ACPI)) {
683                 printk(KERN_ERR PREFIX
684                         "HARDWARE addr space,NOT supported yet\n");
685         } else {
686                 msr = value;
687                 wrmsr_safe(MSR_IA32_THERM_CONTROL,
688                         msr & 0xffffffff, msr >> 32);
689                 ret = 0;
690         }
691         return ret;
692 }
693 #else
694 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
695                                 acpi_integer * value)
696 {
697         printk(KERN_ERR PREFIX
698                 "HARDWARE addr space,NOT supported yet\n");
699         return -1;
700 }
701
702 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
703 {
704         printk(KERN_ERR PREFIX
705                 "HARDWARE addr space,NOT supported yet\n");
706         return -1;
707 }
708 #endif
709
710 static int acpi_read_throttling_status(struct acpi_processor *pr,
711                                         acpi_integer *value)
712 {
713         u32 bit_width, bit_offset;
714         u64 ptc_value;
715         u64 ptc_mask;
716         struct acpi_processor_throttling *throttling;
717         int ret = -1;
718
719         throttling = &pr->throttling;
720         switch (throttling->status_register.space_id) {
721         case ACPI_ADR_SPACE_SYSTEM_IO:
722                 ptc_value = 0;
723                 bit_width = throttling->status_register.bit_width;
724                 bit_offset = throttling->status_register.bit_offset;
725
726                 acpi_os_read_port((acpi_io_address) throttling->status_register.
727                                   address, (u32 *) &ptc_value,
728                                   (u32) (bit_width + bit_offset));
729                 ptc_mask = (1 << bit_width) - 1;
730                 *value = (acpi_integer) ((ptc_value >> bit_offset) & ptc_mask);
731                 ret = 0;
732                 break;
733         case ACPI_ADR_SPACE_FIXED_HARDWARE:
734                 ret = acpi_throttling_rdmsr(pr, value);
735                 break;
736         default:
737                 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
738                        (u32) (throttling->status_register.space_id));
739         }
740         return ret;
741 }
742
743 static int acpi_write_throttling_state(struct acpi_processor *pr,
744                                 acpi_integer value)
745 {
746         u32 bit_width, bit_offset;
747         u64 ptc_value;
748         u64 ptc_mask;
749         struct acpi_processor_throttling *throttling;
750         int ret = -1;
751
752         throttling = &pr->throttling;
753         switch (throttling->control_register.space_id) {
754         case ACPI_ADR_SPACE_SYSTEM_IO:
755                 bit_width = throttling->control_register.bit_width;
756                 bit_offset = throttling->control_register.bit_offset;
757                 ptc_mask = (1 << bit_width) - 1;
758                 ptc_value = value & ptc_mask;
759
760                 acpi_os_write_port((acpi_io_address) throttling->
761                                         control_register.address,
762                                         (u32) (ptc_value << bit_offset),
763                                         (u32) (bit_width + bit_offset));
764                 ret = 0;
765                 break;
766         case ACPI_ADR_SPACE_FIXED_HARDWARE:
767                 ret = acpi_throttling_wrmsr(pr, value);
768                 break;
769         default:
770                 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
771                        (u32) (throttling->control_register.space_id));
772         }
773         return ret;
774 }
775
776 static int acpi_get_throttling_state(struct acpi_processor *pr,
777                                 acpi_integer value)
778 {
779         int i;
780
781         for (i = 0; i < pr->throttling.state_count; i++) {
782                 struct acpi_processor_tx_tss *tx =
783                     (struct acpi_processor_tx_tss *)&(pr->throttling.
784                                                       states_tss[i]);
785                 if (tx->control == value)
786                         break;
787         }
788         if (i > pr->throttling.state_count)
789                 i = -1;
790         return i;
791 }
792
793 static int acpi_get_throttling_value(struct acpi_processor *pr,
794                         int state, acpi_integer *value)
795 {
796         int ret = -1;
797
798         if (state >= 0 && state <= pr->throttling.state_count) {
799                 struct acpi_processor_tx_tss *tx =
800                     (struct acpi_processor_tx_tss *)&(pr->throttling.
801                                                       states_tss[state]);
802                 *value = tx->control;
803                 ret = 0;
804         }
805         return ret;
806 }
807
808 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
809 {
810         int state = 0;
811         int ret;
812         acpi_integer value;
813
814         if (!pr)
815                 return -EINVAL;
816
817         if (!pr->flags.throttling)
818                 return -ENODEV;
819
820         pr->throttling.state = 0;
821
822         value = 0;
823         ret = acpi_read_throttling_status(pr, &value);
824         if (ret >= 0) {
825                 state = acpi_get_throttling_state(pr, value);
826                 pr->throttling.state = state;
827         }
828
829         return 0;
830 }
831
832 static int acpi_processor_get_throttling(struct acpi_processor *pr)
833 {
834         cpumask_var_t saved_mask;
835         int ret;
836
837         if (!pr)
838                 return -EINVAL;
839
840         if (!pr->flags.throttling)
841                 return -ENODEV;
842
843         if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
844                 return -ENOMEM;
845
846         /*
847          * Migrate task to the cpu pointed by pr.
848          */
849         cpumask_copy(saved_mask, &current->cpus_allowed);
850         /* FIXME: use work_on_cpu() */
851         set_cpus_allowed_ptr(current, cpumask_of(pr->id));
852         ret = pr->throttling.acpi_processor_get_throttling(pr);
853         /* restore the previous state */
854         set_cpus_allowed_ptr(current, saved_mask);
855         free_cpumask_var(saved_mask);
856
857         return ret;
858 }
859
860 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
861 {
862         int i, step;
863
864         if (!pr->throttling.address) {
865                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
866                 return -EINVAL;
867         } else if (!pr->throttling.duty_width) {
868                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
869                 return -EINVAL;
870         }
871         /* TBD: Support duty_cycle values that span bit 4. */
872         else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
873                 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
874                 return -EINVAL;
875         }
876
877         pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
878
879         /*
880          * Compute state values. Note that throttling displays a linear power
881          * performance relationship (at 50% performance the CPU will consume
882          * 50% power).  Values are in 1/10th of a percent to preserve accuracy.
883          */
884
885         step = (1000 / pr->throttling.state_count);
886
887         for (i = 0; i < pr->throttling.state_count; i++) {
888                 pr->throttling.states[i].performance = 1000 - step * i;
889                 pr->throttling.states[i].power = 1000 - step * i;
890         }
891         return 0;
892 }
893
894 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
895                                               int state)
896 {
897         u32 value = 0;
898         u32 duty_mask = 0;
899         u32 duty_value = 0;
900
901         if (!pr)
902                 return -EINVAL;
903
904         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
905                 return -EINVAL;
906
907         if (!pr->flags.throttling)
908                 return -ENODEV;
909
910         if (state == pr->throttling.state)
911                 return 0;
912
913         if (state < pr->throttling_platform_limit)
914                 return -EPERM;
915         /*
916          * Calculate the duty_value and duty_mask.
917          */
918         if (state) {
919                 duty_value = pr->throttling.state_count - state;
920
921                 duty_value <<= pr->throttling.duty_offset;
922
923                 /* Used to clear all duty_value bits */
924                 duty_mask = pr->throttling.state_count - 1;
925
926                 duty_mask <<= acpi_gbl_FADT.duty_offset;
927                 duty_mask = ~duty_mask;
928         }
929
930         local_irq_disable();
931
932         /*
933          * Disable throttling by writing a 0 to bit 4.  Note that we must
934          * turn it off before you can change the duty_value.
935          */
936         value = inl(pr->throttling.address);
937         if (value & 0x10) {
938                 value &= 0xFFFFFFEF;
939                 outl(value, pr->throttling.address);
940         }
941
942         /*
943          * Write the new duty_value and then enable throttling.  Note
944          * that a state value of 0 leaves throttling disabled.
945          */
946         if (state) {
947                 value &= duty_mask;
948                 value |= duty_value;
949                 outl(value, pr->throttling.address);
950
951                 value |= 0x00000010;
952                 outl(value, pr->throttling.address);
953         }
954
955         pr->throttling.state = state;
956
957         local_irq_enable();
958
959         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
960                           "Throttling state set to T%d (%d%%)\n", state,
961                           (pr->throttling.states[state].performance ? pr->
962                            throttling.states[state].performance / 10 : 0)));
963
964         return 0;
965 }
966
967 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
968                                              int state)
969 {
970         int ret;
971         acpi_integer value;
972
973         if (!pr)
974                 return -EINVAL;
975
976         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
977                 return -EINVAL;
978
979         if (!pr->flags.throttling)
980                 return -ENODEV;
981
982         if (state == pr->throttling.state)
983                 return 0;
984
985         if (state < pr->throttling_platform_limit)
986                 return -EPERM;
987
988         value = 0;
989         ret = acpi_get_throttling_value(pr, state, &value);
990         if (ret >= 0) {
991                 acpi_write_throttling_state(pr, value);
992                 pr->throttling.state = state;
993         }
994
995         return 0;
996 }
997
998 int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
999 {
1000         cpumask_var_t saved_mask;
1001         int ret = 0;
1002         unsigned int i;
1003         struct acpi_processor *match_pr;
1004         struct acpi_processor_throttling *p_throttling;
1005         struct throttling_tstate t_state;
1006         cpumask_var_t online_throttling_cpus;
1007
1008         if (!pr)
1009                 return -EINVAL;
1010
1011         if (!pr->flags.throttling)
1012                 return -ENODEV;
1013
1014         if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1015                 return -EINVAL;
1016
1017         if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1018                 return -ENOMEM;
1019
1020         if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1021                 free_cpumask_var(saved_mask);
1022                 return -ENOMEM;
1023         }
1024
1025         cpumask_copy(saved_mask, &current->cpus_allowed);
1026         t_state.target_state = state;
1027         p_throttling = &(pr->throttling);
1028         cpumask_and(online_throttling_cpus, cpu_online_mask,
1029                     p_throttling->shared_cpu_map);
1030         /*
1031          * The throttling notifier will be called for every
1032          * affected cpu in order to get one proper T-state.
1033          * The notifier event is THROTTLING_PRECHANGE.
1034          */
1035         for_each_cpu(i, online_throttling_cpus) {
1036                 t_state.cpu = i;
1037                 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1038                                                         &t_state);
1039         }
1040         /*
1041          * The function of acpi_processor_set_throttling will be called
1042          * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1043          * it is necessary to call it for every affected cpu. Otherwise
1044          * it can be called only for the cpu pointed by pr.
1045          */
1046         if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1047                 /* FIXME: use work_on_cpu() */
1048                 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
1049                 ret = p_throttling->acpi_processor_set_throttling(pr,
1050                                                 t_state.target_state);
1051         } else {
1052                 /*
1053                  * When the T-state coordination is SW_ALL or HW_ALL,
1054                  * it is necessary to set T-state for every affected
1055                  * cpus.
1056                  */
1057                 for_each_cpu(i, online_throttling_cpus) {
1058                         match_pr = per_cpu(processors, i);
1059                         /*
1060                          * If the pointer is invalid, we will report the
1061                          * error message and continue.
1062                          */
1063                         if (!match_pr) {
1064                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1065                                         "Invalid Pointer for CPU %d\n", i));
1066                                 continue;
1067                         }
1068                         /*
1069                          * If the throttling control is unsupported on CPU i,
1070                          * we will report the error message and continue.
1071                          */
1072                         if (!match_pr->flags.throttling) {
1073                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1074                                         "Throttling Controll is unsupported "
1075                                         "on CPU %d\n", i));
1076                                 continue;
1077                         }
1078                         t_state.cpu = i;
1079                         /* FIXME: use work_on_cpu() */
1080                         set_cpus_allowed_ptr(current, cpumask_of(i));
1081                         ret = match_pr->throttling.
1082                                 acpi_processor_set_throttling(
1083                                 match_pr, t_state.target_state);
1084                 }
1085         }
1086         /*
1087          * After the set_throttling is called, the
1088          * throttling notifier is called for every
1089          * affected cpu to update the T-states.
1090          * The notifier event is THROTTLING_POSTCHANGE
1091          */
1092         for_each_cpu(i, online_throttling_cpus) {
1093                 t_state.cpu = i;
1094                 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1095                                                         &t_state);
1096         }
1097         /* restore the previous state */
1098         /* FIXME: use work_on_cpu() */
1099         set_cpus_allowed_ptr(current, saved_mask);
1100         free_cpumask_var(online_throttling_cpus);
1101         free_cpumask_var(saved_mask);
1102         return ret;
1103 }
1104
1105 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1106 {
1107         int result = 0;
1108         struct acpi_processor_throttling *pthrottling;
1109
1110         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1111                           "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1112                           pr->throttling.address,
1113                           pr->throttling.duty_offset,
1114                           pr->throttling.duty_width));
1115
1116         if (!pr)
1117                 return -EINVAL;
1118
1119         /*
1120          * Evaluate _PTC, _TSS and _TPC
1121          * They must all be present or none of them can be used.
1122          */
1123         if (acpi_processor_get_throttling_control(pr) ||
1124                 acpi_processor_get_throttling_states(pr) ||
1125                 acpi_processor_get_platform_limit(pr))
1126         {
1127                 pr->throttling.acpi_processor_get_throttling =
1128                     &acpi_processor_get_throttling_fadt;
1129                 pr->throttling.acpi_processor_set_throttling =
1130                     &acpi_processor_set_throttling_fadt;
1131                 if (acpi_processor_get_fadt_info(pr))
1132                         return 0;
1133         } else {
1134                 pr->throttling.acpi_processor_get_throttling =
1135                     &acpi_processor_get_throttling_ptc;
1136                 pr->throttling.acpi_processor_set_throttling =
1137                     &acpi_processor_set_throttling_ptc;
1138         }
1139
1140         /*
1141          * If TSD package for one CPU can't be parsed successfully, it means
1142          * that this CPU will have no coordination with other CPUs.
1143          */
1144         if (acpi_processor_get_tsd(pr)) {
1145                 pthrottling = &pr->throttling;
1146                 pthrottling->tsd_valid_flag = 0;
1147                 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1148                 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1149         }
1150
1151         /*
1152          * PIIX4 Errata: We don't support throttling on the original PIIX4.
1153          * This shouldn't be an issue as few (if any) mobile systems ever
1154          * used this part.
1155          */
1156         if (errata.piix4.throttle) {
1157                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1158                                   "Throttling not supported on PIIX4 A- or B-step\n"));
1159                 return 0;
1160         }
1161
1162         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1163                           pr->throttling.state_count));
1164
1165         pr->flags.throttling = 1;
1166
1167         /*
1168          * Disable throttling (if enabled).  We'll let subsequent policy (e.g.
1169          * thermal) decide to lower performance if it so chooses, but for now
1170          * we'll crank up the speed.
1171          */
1172
1173         result = acpi_processor_get_throttling(pr);
1174         if (result)
1175                 goto end;
1176
1177         if (pr->throttling.state) {
1178                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1179                                   "Disabling throttling (was T%d)\n",
1180                                   pr->throttling.state));
1181                 result = acpi_processor_set_throttling(pr, 0);
1182                 if (result)
1183                         goto end;
1184         }
1185
1186       end:
1187         if (result)
1188                 pr->flags.throttling = 0;
1189
1190         return result;
1191 }
1192
1193 /* proc interface */
1194
1195 static int acpi_processor_throttling_seq_show(struct seq_file *seq,
1196                                               void *offset)
1197 {
1198         struct acpi_processor *pr = seq->private;
1199         int i = 0;
1200         int result = 0;
1201
1202         if (!pr)
1203                 goto end;
1204
1205         if (!(pr->throttling.state_count > 0)) {
1206                 seq_puts(seq, "<not supported>\n");
1207                 goto end;
1208         }
1209
1210         result = acpi_processor_get_throttling(pr);
1211
1212         if (result) {
1213                 seq_puts(seq,
1214                          "Could not determine current throttling state.\n");
1215                 goto end;
1216         }
1217
1218         seq_printf(seq, "state count:             %d\n"
1219                    "active state:            T%d\n"
1220                    "state available: T%d to T%d\n",
1221                    pr->throttling.state_count, pr->throttling.state,
1222                    pr->throttling_platform_limit,
1223                    pr->throttling.state_count - 1);
1224
1225         seq_puts(seq, "states:\n");
1226         if (pr->throttling.acpi_processor_get_throttling ==
1227                         acpi_processor_get_throttling_fadt) {
1228                 for (i = 0; i < pr->throttling.state_count; i++)
1229                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1230                                    (i == pr->throttling.state ? '*' : ' '), i,
1231                                    (pr->throttling.states[i].performance ? pr->
1232                                     throttling.states[i].performance / 10 : 0));
1233         } else {
1234                 for (i = 0; i < pr->throttling.state_count; i++)
1235                         seq_printf(seq, "   %cT%d:                  %02d%%\n",
1236                                    (i == pr->throttling.state ? '*' : ' '), i,
1237                                    (int)pr->throttling.states_tss[i].
1238                                    freqpercentage);
1239         }
1240
1241       end:
1242         return 0;
1243 }
1244
1245 static int acpi_processor_throttling_open_fs(struct inode *inode,
1246                                              struct file *file)
1247 {
1248         return single_open(file, acpi_processor_throttling_seq_show,
1249                            PDE(inode)->data);
1250 }
1251
1252 static ssize_t acpi_processor_write_throttling(struct file *file,
1253                                                const char __user * buffer,
1254                                                size_t count, loff_t * data)
1255 {
1256         int result = 0;
1257         struct seq_file *m = file->private_data;
1258         struct acpi_processor *pr = m->private;
1259         char state_string[5] = "";
1260         char *charp = NULL;
1261         size_t state_val = 0;
1262         char tmpbuf[5] = "";
1263
1264         if (!pr || (count > sizeof(state_string) - 1))
1265                 return -EINVAL;
1266
1267         if (copy_from_user(state_string, buffer, count))
1268                 return -EFAULT;
1269
1270         state_string[count] = '\0';
1271         if ((count > 0) && (state_string[count-1] == '\n'))
1272                 state_string[count-1] = '\0';
1273
1274         charp = state_string;
1275         if ((state_string[0] == 't') || (state_string[0] == 'T'))
1276                 charp++;
1277
1278         state_val = simple_strtoul(charp, NULL, 0);
1279         if (state_val >= pr->throttling.state_count)
1280                 return -EINVAL;
1281
1282         snprintf(tmpbuf, 5, "%zu", state_val);
1283
1284         if (strcmp(tmpbuf, charp) != 0)
1285                 return -EINVAL;
1286
1287         result = acpi_processor_set_throttling(pr, state_val);
1288         if (result)
1289                 return result;
1290
1291         return count;
1292 }
1293
1294 struct file_operations acpi_processor_throttling_fops = {
1295         .owner = THIS_MODULE,
1296         .open = acpi_processor_throttling_open_fs,
1297         .read = seq_read,
1298         .write = acpi_processor_write_throttling,
1299         .llseek = seq_lseek,
1300         .release = single_release,
1301 };