[ACPI] merge 3549 4320 4485 4588 4980 5483 5651 acpica asus fops pnpacpi branches...
[linux-2.6.git] / drivers / acpi / processor_perflib.c
1 /*
2  * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
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  *
13  *  This program is free software; you can redistribute it and/or modify
14  *  it under the terms of the GNU General Public License as published by
15  *  the Free Software Foundation; either version 2 of the License, or (at
16  *  your option) any later version.
17  *
18  *  This program is distributed in the hope that it will be useful, but
19  *  WITHOUT ANY WARRANTY; without even the implied warranty of
20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
21  *  General Public License for more details.
22  *
23  *  You should have received a copy of the GNU General Public License along
24  *  with this program; if not, write to the Free Software Foundation, Inc.,
25  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
26  *
27  */
28
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/cpufreq.h>
33
34 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
35 #include <linux/proc_fs.h>
36 #include <linux/seq_file.h>
37
38 #include <asm/uaccess.h>
39 #endif
40
41 #include <acpi/acpi_bus.h>
42 #include <acpi/processor.h>
43
44 #define ACPI_PROCESSOR_COMPONENT        0x01000000
45 #define ACPI_PROCESSOR_CLASS            "processor"
46 #define ACPI_PROCESSOR_DRIVER_NAME      "ACPI Processor Driver"
47 #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
48 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
49 ACPI_MODULE_NAME("acpi_processor")
50
51 static DECLARE_MUTEX(performance_sem);
52
53 /*
54  * _PPC support is implemented as a CPUfreq policy notifier:
55  * This means each time a CPUfreq driver registered also with
56  * the ACPI core is asked to change the speed policy, the maximum
57  * value is adjusted so that it is within the platform limit.
58  *
59  * Also, when a new platform limit value is detected, the CPUfreq
60  * policy is adjusted accordingly.
61  */
62
63 #define PPC_REGISTERED   1
64 #define PPC_IN_USE       2
65
66 static int acpi_processor_ppc_status = 0;
67
68 static int acpi_processor_ppc_notifier(struct notifier_block *nb,
69                                        unsigned long event, void *data)
70 {
71         struct cpufreq_policy *policy = data;
72         struct acpi_processor *pr;
73         unsigned int ppc = 0;
74
75         down(&performance_sem);
76
77         if (event != CPUFREQ_INCOMPATIBLE)
78                 goto out;
79
80         pr = processors[policy->cpu];
81         if (!pr || !pr->performance)
82                 goto out;
83
84         ppc = (unsigned int)pr->performance_platform_limit;
85         if (!ppc)
86                 goto out;
87
88         if (ppc > pr->performance->state_count)
89                 goto out;
90
91         cpufreq_verify_within_limits(policy, 0,
92                                      pr->performance->states[ppc].
93                                      core_frequency * 1000);
94
95       out:
96         up(&performance_sem);
97
98         return 0;
99 }
100
101 static struct notifier_block acpi_ppc_notifier_block = {
102         .notifier_call = acpi_processor_ppc_notifier,
103 };
104
105 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
106 {
107         acpi_status status = 0;
108         unsigned long ppc = 0;
109
110         ACPI_FUNCTION_TRACE("acpi_processor_get_platform_limit");
111
112         if (!pr)
113                 return_VALUE(-EINVAL);
114
115         /*
116          * _PPC indicates the maximum state currently supported by the platform
117          * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
118          */
119         status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
120
121         if (status != AE_NOT_FOUND)
122                 acpi_processor_ppc_status |= PPC_IN_USE;
123
124         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
125                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PPC\n"));
126                 return_VALUE(-ENODEV);
127         }
128
129         pr->performance_platform_limit = (int)ppc;
130
131         return_VALUE(0);
132 }
133
134 int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
135 {
136         int ret = acpi_processor_get_platform_limit(pr);
137         if (ret < 0)
138                 return (ret);
139         else
140                 return cpufreq_update_policy(pr->id);
141 }
142
143 void acpi_processor_ppc_init(void)
144 {
145         if (!cpufreq_register_notifier
146             (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
147                 acpi_processor_ppc_status |= PPC_REGISTERED;
148         else
149                 printk(KERN_DEBUG
150                        "Warning: Processor Platform Limit not supported.\n");
151 }
152
153 void acpi_processor_ppc_exit(void)
154 {
155         if (acpi_processor_ppc_status & PPC_REGISTERED)
156                 cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
157                                             CPUFREQ_POLICY_NOTIFIER);
158
159         acpi_processor_ppc_status &= ~PPC_REGISTERED;
160 }
161
162 static int acpi_processor_get_performance_control(struct acpi_processor *pr)
163 {
164         int result = 0;
165         acpi_status status = 0;
166         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
167         union acpi_object *pct = NULL;
168         union acpi_object obj = { 0 };
169
170         ACPI_FUNCTION_TRACE("acpi_processor_get_performance_control");
171
172         status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
173         if (ACPI_FAILURE(status)) {
174                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PCT\n"));
175                 return_VALUE(-ENODEV);
176         }
177
178         pct = (union acpi_object *)buffer.pointer;
179         if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
180             || (pct->package.count != 2)) {
181                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PCT data\n"));
182                 result = -EFAULT;
183                 goto end;
184         }
185
186         /*
187          * control_register
188          */
189
190         obj = pct->package.elements[0];
191
192         if ((obj.type != ACPI_TYPE_BUFFER)
193             || (obj.buffer.length < sizeof(struct acpi_pct_register))
194             || (obj.buffer.pointer == NULL)) {
195                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
196                                   "Invalid _PCT data (control_register)\n"));
197                 result = -EFAULT;
198                 goto end;
199         }
200         memcpy(&pr->performance->control_register, obj.buffer.pointer,
201                sizeof(struct acpi_pct_register));
202
203         /*
204          * status_register
205          */
206
207         obj = pct->package.elements[1];
208
209         if ((obj.type != ACPI_TYPE_BUFFER)
210             || (obj.buffer.length < sizeof(struct acpi_pct_register))
211             || (obj.buffer.pointer == NULL)) {
212                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
213                                   "Invalid _PCT data (status_register)\n"));
214                 result = -EFAULT;
215                 goto end;
216         }
217
218         memcpy(&pr->performance->status_register, obj.buffer.pointer,
219                sizeof(struct acpi_pct_register));
220
221       end:
222         acpi_os_free(buffer.pointer);
223
224         return_VALUE(result);
225 }
226
227 static int acpi_processor_get_performance_states(struct acpi_processor *pr)
228 {
229         int result = 0;
230         acpi_status status = AE_OK;
231         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
232         struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" };
233         struct acpi_buffer state = { 0, NULL };
234         union acpi_object *pss = NULL;
235         int i;
236
237         ACPI_FUNCTION_TRACE("acpi_processor_get_performance_states");
238
239         status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
240         if (ACPI_FAILURE(status)) {
241                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PSS\n"));
242                 return_VALUE(-ENODEV);
243         }
244
245         pss = (union acpi_object *)buffer.pointer;
246         if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
247                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data\n"));
248                 result = -EFAULT;
249                 goto end;
250         }
251
252         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
253                           pss->package.count));
254
255         pr->performance->state_count = pss->package.count;
256         pr->performance->states =
257             kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
258                     GFP_KERNEL);
259         if (!pr->performance->states) {
260                 result = -ENOMEM;
261                 goto end;
262         }
263
264         for (i = 0; i < pr->performance->state_count; i++) {
265
266                 struct acpi_processor_px *px = &(pr->performance->states[i]);
267
268                 state.length = sizeof(struct acpi_processor_px);
269                 state.pointer = px;
270
271                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
272
273                 status = acpi_extract_package(&(pss->package.elements[i]),
274                                               &format, &state);
275                 if (ACPI_FAILURE(status)) {
276                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
277                                           "Invalid _PSS data\n"));
278                         result = -EFAULT;
279                         kfree(pr->performance->states);
280                         goto end;
281                 }
282
283                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
284                                   "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
285                                   i,
286                                   (u32) px->core_frequency,
287                                   (u32) px->power,
288                                   (u32) px->transition_latency,
289                                   (u32) px->bus_master_latency,
290                                   (u32) px->control, (u32) px->status));
291
292                 if (!px->core_frequency) {
293                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
294                                           "Invalid _PSS data: freq is zero\n"));
295                         result = -EFAULT;
296                         kfree(pr->performance->states);
297                         goto end;
298                 }
299         }
300
301       end:
302         acpi_os_free(buffer.pointer);
303
304         return_VALUE(result);
305 }
306
307 static int acpi_processor_get_performance_info(struct acpi_processor *pr)
308 {
309         int result = 0;
310         acpi_status status = AE_OK;
311         acpi_handle handle = NULL;
312
313         ACPI_FUNCTION_TRACE("acpi_processor_get_performance_info");
314
315         if (!pr || !pr->performance || !pr->handle)
316                 return_VALUE(-EINVAL);
317
318         status = acpi_get_handle(pr->handle, "_PCT", &handle);
319         if (ACPI_FAILURE(status)) {
320                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
321                                   "ACPI-based processor performance control unavailable\n"));
322                 return_VALUE(-ENODEV);
323         }
324
325         result = acpi_processor_get_performance_control(pr);
326         if (result)
327                 return_VALUE(result);
328
329         result = acpi_processor_get_performance_states(pr);
330         if (result)
331                 return_VALUE(result);
332
333         result = acpi_processor_get_platform_limit(pr);
334         if (result)
335                 return_VALUE(result);
336
337         return_VALUE(0);
338 }
339
340 int acpi_processor_notify_smm(struct module *calling_module)
341 {
342         acpi_status status;
343         static int is_done = 0;
344
345         ACPI_FUNCTION_TRACE("acpi_processor_notify_smm");
346
347         if (!(acpi_processor_ppc_status & PPC_REGISTERED))
348                 return_VALUE(-EBUSY);
349
350         if (!try_module_get(calling_module))
351                 return_VALUE(-EINVAL);
352
353         /* is_done is set to negative if an error occured,
354          * and to postitive if _no_ error occured, but SMM
355          * was already notified. This avoids double notification
356          * which might lead to unexpected results...
357          */
358         if (is_done > 0) {
359                 module_put(calling_module);
360                 return_VALUE(0);
361         } else if (is_done < 0) {
362                 module_put(calling_module);
363                 return_VALUE(is_done);
364         }
365
366         is_done = -EIO;
367
368         /* Can't write pstate_cnt to smi_cmd if either value is zero */
369         if ((!acpi_fadt.smi_cmd) || (!acpi_fadt.pstate_cnt)) {
370                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_cnt\n"));
371                 module_put(calling_module);
372                 return_VALUE(0);
373         }
374
375         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
376                           "Writing pstate_cnt [0x%x] to smi_cmd [0x%x]\n",
377                           acpi_fadt.pstate_cnt, acpi_fadt.smi_cmd));
378
379         /* FADT v1 doesn't support pstate_cnt, many BIOS vendors use
380          * it anyway, so we need to support it... */
381         if (acpi_fadt_is_v1) {
382                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
383                                   "Using v1.0 FADT reserved value for pstate_cnt\n"));
384         }
385
386         status = acpi_os_write_port(acpi_fadt.smi_cmd,
387                                     (u32) acpi_fadt.pstate_cnt, 8);
388         if (ACPI_FAILURE(status)) {
389                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
390                                   "Failed to write pstate_cnt [0x%x] to "
391                                   "smi_cmd [0x%x]\n", acpi_fadt.pstate_cnt,
392                                   acpi_fadt.smi_cmd));
393                 module_put(calling_module);
394                 return_VALUE(status);
395         }
396
397         /* Success. If there's no _PPC, we need to fear nothing, so
398          * we can allow the cpufreq driver to be rmmod'ed. */
399         is_done = 1;
400
401         if (!(acpi_processor_ppc_status & PPC_IN_USE))
402                 module_put(calling_module);
403
404         return_VALUE(0);
405 }
406
407 EXPORT_SYMBOL(acpi_processor_notify_smm);
408
409 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
410 /* /proc/acpi/processor/../performance interface (DEPRECATED) */
411
412 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file);
413 static struct file_operations acpi_processor_perf_fops = {
414         .open = acpi_processor_perf_open_fs,
415         .read = seq_read,
416         .llseek = seq_lseek,
417         .release = single_release,
418 };
419
420 static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset)
421 {
422         struct acpi_processor *pr = (struct acpi_processor *)seq->private;
423         int i;
424
425         ACPI_FUNCTION_TRACE("acpi_processor_perf_seq_show");
426
427         if (!pr)
428                 goto end;
429
430         if (!pr->performance) {
431                 seq_puts(seq, "<not supported>\n");
432                 goto end;
433         }
434
435         seq_printf(seq, "state count:             %d\n"
436                    "active state:            P%d\n",
437                    pr->performance->state_count, pr->performance->state);
438
439         seq_puts(seq, "states:\n");
440         for (i = 0; i < pr->performance->state_count; i++)
441                 seq_printf(seq,
442                            "   %cP%d:                  %d MHz, %d mW, %d uS\n",
443                            (i == pr->performance->state ? '*' : ' '), i,
444                            (u32) pr->performance->states[i].core_frequency,
445                            (u32) pr->performance->states[i].power,
446                            (u32) pr->performance->states[i].transition_latency);
447
448       end:
449         return_VALUE(0);
450 }
451
452 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file)
453 {
454         return single_open(file, acpi_processor_perf_seq_show,
455                            PDE(inode)->data);
456 }
457
458 static ssize_t
459 acpi_processor_write_performance(struct file *file,
460                                  const char __user * buffer,
461                                  size_t count, loff_t * data)
462 {
463         int result = 0;
464         struct seq_file *m = (struct seq_file *)file->private_data;
465         struct acpi_processor *pr = (struct acpi_processor *)m->private;
466         struct acpi_processor_performance *perf;
467         char state_string[12] = { '\0' };
468         unsigned int new_state = 0;
469         struct cpufreq_policy policy;
470
471         ACPI_FUNCTION_TRACE("acpi_processor_write_performance");
472
473         if (!pr || (count > sizeof(state_string) - 1))
474                 return_VALUE(-EINVAL);
475
476         perf = pr->performance;
477         if (!perf)
478                 return_VALUE(-EINVAL);
479
480         if (copy_from_user(state_string, buffer, count))
481                 return_VALUE(-EFAULT);
482
483         state_string[count] = '\0';
484         new_state = simple_strtoul(state_string, NULL, 0);
485
486         if (new_state >= perf->state_count)
487                 return_VALUE(-EINVAL);
488
489         cpufreq_get_policy(&policy, pr->id);
490
491         policy.cpu = pr->id;
492         policy.min = perf->states[new_state].core_frequency * 1000;
493         policy.max = perf->states[new_state].core_frequency * 1000;
494
495         result = cpufreq_set_policy(&policy);
496         if (result)
497                 return_VALUE(result);
498
499         return_VALUE(count);
500 }
501
502 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
503 {
504         struct proc_dir_entry *entry = NULL;
505         struct acpi_device *device = NULL;
506
507         ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile");
508
509         if (acpi_bus_get_device(pr->handle, &device))
510                 return_VOID;
511
512         /* add file 'performance' [R/W] */
513         entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
514                                   S_IFREG | S_IRUGO | S_IWUSR,
515                                   acpi_device_dir(device));
516         if (!entry)
517                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
518                                   "Unable to create '%s' fs entry\n",
519                                   ACPI_PROCESSOR_FILE_PERFORMANCE));
520         else {
521                 acpi_processor_perf_fops.write = acpi_processor_write_performance;
522                 entry->proc_fops = &acpi_processor_perf_fops;
523                 entry->data = acpi_driver_data(device);
524                 entry->owner = THIS_MODULE;
525         }
526         return_VOID;
527 }
528
529 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
530 {
531         struct acpi_device *device = NULL;
532
533         ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile");
534
535         if (acpi_bus_get_device(pr->handle, &device))
536                 return_VOID;
537
538         /* remove file 'performance' */
539         remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
540                           acpi_device_dir(device));
541
542         return_VOID;
543 }
544
545 #else
546 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
547 {
548         return;
549 }
550 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
551 {
552         return;
553 }
554 #endif                          /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */
555
556 int
557 acpi_processor_register_performance(struct acpi_processor_performance
558                                     *performance, unsigned int cpu)
559 {
560         struct acpi_processor *pr;
561
562         ACPI_FUNCTION_TRACE("acpi_processor_register_performance");
563
564         if (!(acpi_processor_ppc_status & PPC_REGISTERED))
565                 return_VALUE(-EINVAL);
566
567         down(&performance_sem);
568
569         pr = processors[cpu];
570         if (!pr) {
571                 up(&performance_sem);
572                 return_VALUE(-ENODEV);
573         }
574
575         if (pr->performance) {
576                 up(&performance_sem);
577                 return_VALUE(-EBUSY);
578         }
579
580         pr->performance = performance;
581
582         if (acpi_processor_get_performance_info(pr)) {
583                 pr->performance = NULL;
584                 up(&performance_sem);
585                 return_VALUE(-EIO);
586         }
587
588         acpi_cpufreq_add_file(pr);
589
590         up(&performance_sem);
591         return_VALUE(0);
592 }
593
594 EXPORT_SYMBOL(acpi_processor_register_performance);
595
596 void
597 acpi_processor_unregister_performance(struct acpi_processor_performance
598                                       *performance, unsigned int cpu)
599 {
600         struct acpi_processor *pr;
601
602         ACPI_FUNCTION_TRACE("acpi_processor_unregister_performance");
603
604         down(&performance_sem);
605
606         pr = processors[cpu];
607         if (!pr) {
608                 up(&performance_sem);
609                 return_VOID;
610         }
611
612         kfree(pr->performance->states);
613         pr->performance = NULL;
614
615         acpi_cpufreq_remove_file(pr);
616
617         up(&performance_sem);
618
619         return_VOID;
620 }
621
622 EXPORT_SYMBOL(acpi_processor_unregister_performance);