acpi-cpufreq: Fix some x86/x86-64 acpi-cpufreq driver issues
[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 #include <linux/mutex.h>
38
39 #include <asm/uaccess.h>
40 #endif
41
42 #include <acpi/acpi_bus.h>
43 #include <acpi/processor.h>
44
45 #define ACPI_PROCESSOR_COMPONENT        0x01000000
46 #define ACPI_PROCESSOR_CLASS            "processor"
47 #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
48 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
49 ACPI_MODULE_NAME("processor_perflib");
50
51 static DEFINE_MUTEX(performance_mutex);
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         mutex_lock(&performance_mutex);
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
86         if (ppc >= pr->performance->state_count)
87                 goto out;
88
89         cpufreq_verify_within_limits(policy, 0,
90                                      pr->performance->states[ppc].
91                                      core_frequency * 1000);
92
93       out:
94         mutex_unlock(&performance_mutex);
95
96         return 0;
97 }
98
99 static struct notifier_block acpi_ppc_notifier_block = {
100         .notifier_call = acpi_processor_ppc_notifier,
101 };
102
103 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
104 {
105         acpi_status status = 0;
106         unsigned long ppc = 0;
107
108
109         if (!pr)
110                 return -EINVAL;
111
112         /*
113          * _PPC indicates the maximum state currently supported by the platform
114          * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
115          */
116         status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
117
118         if (status != AE_NOT_FOUND)
119                 acpi_processor_ppc_status |= PPC_IN_USE;
120
121         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
122                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
123                 return -ENODEV;
124         }
125
126         pr->performance_platform_limit = (int)ppc;
127
128         return 0;
129 }
130
131 int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
132 {
133         int ret = acpi_processor_get_platform_limit(pr);
134         if (ret < 0)
135                 return (ret);
136         else
137                 return cpufreq_update_policy(pr->id);
138 }
139
140 void acpi_processor_ppc_init(void)
141 {
142         if (!cpufreq_register_notifier
143             (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
144                 acpi_processor_ppc_status |= PPC_REGISTERED;
145         else
146                 printk(KERN_DEBUG
147                        "Warning: Processor Platform Limit not supported.\n");
148 }
149
150 void acpi_processor_ppc_exit(void)
151 {
152         if (acpi_processor_ppc_status & PPC_REGISTERED)
153                 cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
154                                             CPUFREQ_POLICY_NOTIFIER);
155
156         acpi_processor_ppc_status &= ~PPC_REGISTERED;
157 }
158
159 static int acpi_processor_get_performance_control(struct acpi_processor *pr)
160 {
161         int result = 0;
162         acpi_status status = 0;
163         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
164         union acpi_object *pct = NULL;
165         union acpi_object obj = { 0 };
166
167
168         status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
169         if (ACPI_FAILURE(status)) {
170                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT"));
171                 return -ENODEV;
172         }
173
174         pct = (union acpi_object *)buffer.pointer;
175         if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
176             || (pct->package.count != 2)) {
177                 printk(KERN_ERR PREFIX "Invalid _PCT data\n");
178                 result = -EFAULT;
179                 goto end;
180         }
181
182         /*
183          * control_register
184          */
185
186         obj = pct->package.elements[0];
187
188         if ((obj.type != ACPI_TYPE_BUFFER)
189             || (obj.buffer.length < sizeof(struct acpi_pct_register))
190             || (obj.buffer.pointer == NULL)) {
191                 printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n");
192                 result = -EFAULT;
193                 goto end;
194         }
195         memcpy(&pr->performance->control_register, obj.buffer.pointer,
196                sizeof(struct acpi_pct_register));
197
198         /*
199          * status_register
200          */
201
202         obj = pct->package.elements[1];
203
204         if ((obj.type != ACPI_TYPE_BUFFER)
205             || (obj.buffer.length < sizeof(struct acpi_pct_register))
206             || (obj.buffer.pointer == NULL)) {
207                 printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n");
208                 result = -EFAULT;
209                 goto end;
210         }
211
212         memcpy(&pr->performance->status_register, obj.buffer.pointer,
213                sizeof(struct acpi_pct_register));
214
215       end:
216         kfree(buffer.pointer);
217
218         return result;
219 }
220
221 static int acpi_processor_get_performance_states(struct acpi_processor *pr)
222 {
223         int result = 0;
224         acpi_status status = AE_OK;
225         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
226         struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" };
227         struct acpi_buffer state = { 0, NULL };
228         union acpi_object *pss = NULL;
229         int i;
230
231
232         status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
233         if (ACPI_FAILURE(status)) {
234                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS"));
235                 return -ENODEV;
236         }
237
238         pss = buffer.pointer;
239         if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
240                 printk(KERN_ERR PREFIX "Invalid _PSS data\n");
241                 result = -EFAULT;
242                 goto end;
243         }
244
245         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
246                           pss->package.count));
247
248         pr->performance->state_count = pss->package.count;
249         pr->performance->states =
250             kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
251                     GFP_KERNEL);
252         if (!pr->performance->states) {
253                 result = -ENOMEM;
254                 goto end;
255         }
256
257         for (i = 0; i < pr->performance->state_count; i++) {
258
259                 struct acpi_processor_px *px = &(pr->performance->states[i]);
260
261                 state.length = sizeof(struct acpi_processor_px);
262                 state.pointer = px;
263
264                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
265
266                 status = acpi_extract_package(&(pss->package.elements[i]),
267                                               &format, &state);
268                 if (ACPI_FAILURE(status)) {
269                         ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data"));
270                         result = -EFAULT;
271                         kfree(pr->performance->states);
272                         goto end;
273                 }
274
275                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
276                                   "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
277                                   i,
278                                   (u32) px->core_frequency,
279                                   (u32) px->power,
280                                   (u32) px->transition_latency,
281                                   (u32) px->bus_master_latency,
282                                   (u32) px->control, (u32) px->status));
283
284                 if (!px->core_frequency) {
285                         printk(KERN_ERR PREFIX
286                                     "Invalid _PSS data: freq is zero\n");
287                         result = -EFAULT;
288                         kfree(pr->performance->states);
289                         goto end;
290                 }
291         }
292
293       end:
294         kfree(buffer.pointer);
295
296         return result;
297 }
298
299 static int acpi_processor_get_performance_info(struct acpi_processor *pr)
300 {
301         int result = 0;
302         acpi_status status = AE_OK;
303         acpi_handle handle = NULL;
304
305
306         if (!pr || !pr->performance || !pr->handle)
307                 return -EINVAL;
308
309         status = acpi_get_handle(pr->handle, "_PCT", &handle);
310         if (ACPI_FAILURE(status)) {
311                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
312                                   "ACPI-based processor performance control unavailable\n"));
313                 return -ENODEV;
314         }
315
316         result = acpi_processor_get_performance_control(pr);
317         if (result)
318                 return result;
319
320         result = acpi_processor_get_performance_states(pr);
321         if (result)
322                 return result;
323
324         return 0;
325 }
326
327 int acpi_processor_notify_smm(struct module *calling_module)
328 {
329         acpi_status status;
330         static int is_done = 0;
331
332
333         if (!(acpi_processor_ppc_status & PPC_REGISTERED))
334                 return -EBUSY;
335
336         if (!try_module_get(calling_module))
337                 return -EINVAL;
338
339         /* is_done is set to negative if an error occured,
340          * and to postitive if _no_ error occured, but SMM
341          * was already notified. This avoids double notification
342          * which might lead to unexpected results...
343          */
344         if (is_done > 0) {
345                 module_put(calling_module);
346                 return 0;
347         } else if (is_done < 0) {
348                 module_put(calling_module);
349                 return is_done;
350         }
351
352         is_done = -EIO;
353
354         /* Can't write pstate_control to smi_command if either value is zero */
355         if ((!acpi_gbl_FADT.smi_command) || (!acpi_gbl_FADT.pstate_control)) {
356                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n"));
357                 module_put(calling_module);
358                 return 0;
359         }
360
361         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
362                           "Writing pstate_control [0x%x] to smi_command [0x%x]\n",
363                           acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command));
364
365         status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
366                                     (u32) acpi_gbl_FADT.pstate_control, 8);
367         if (ACPI_FAILURE(status)) {
368                 ACPI_EXCEPTION((AE_INFO, status,
369                                 "Failed to write pstate_control [0x%x] to "
370                                 "smi_command [0x%x]", acpi_gbl_FADT.pstate_control,
371                                 acpi_gbl_FADT.smi_command));
372                 module_put(calling_module);
373                 return status;
374         }
375
376         /* Success. If there's no _PPC, we need to fear nothing, so
377          * we can allow the cpufreq driver to be rmmod'ed. */
378         is_done = 1;
379
380         if (!(acpi_processor_ppc_status & PPC_IN_USE))
381                 module_put(calling_module);
382
383         return 0;
384 }
385
386 EXPORT_SYMBOL(acpi_processor_notify_smm);
387
388 #ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
389 /* /proc/acpi/processor/../performance interface (DEPRECATED) */
390
391 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file);
392 static struct file_operations acpi_processor_perf_fops = {
393         .open = acpi_processor_perf_open_fs,
394         .read = seq_read,
395         .llseek = seq_lseek,
396         .release = single_release,
397 };
398
399 static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset)
400 {
401         struct acpi_processor *pr = seq->private;
402         int i;
403
404
405         if (!pr)
406                 goto end;
407
408         if (!pr->performance) {
409                 seq_puts(seq, "<not supported>\n");
410                 goto end;
411         }
412
413         seq_printf(seq, "state count:             %d\n"
414                    "active state:            P%d\n",
415                    pr->performance->state_count, pr->performance->state);
416
417         seq_puts(seq, "states:\n");
418         for (i = 0; i < pr->performance->state_count; i++)
419                 seq_printf(seq,
420                            "   %cP%d:                  %d MHz, %d mW, %d uS\n",
421                            (i == pr->performance->state ? '*' : ' '), i,
422                            (u32) pr->performance->states[i].core_frequency,
423                            (u32) pr->performance->states[i].power,
424                            (u32) pr->performance->states[i].transition_latency);
425
426       end:
427         return 0;
428 }
429
430 static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file)
431 {
432         return single_open(file, acpi_processor_perf_seq_show,
433                            PDE(inode)->data);
434 }
435
436 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
437 {
438         struct proc_dir_entry *entry = NULL;
439         struct acpi_device *device = NULL;
440
441
442         if (acpi_bus_get_device(pr->handle, &device))
443                 return;
444
445         /* add file 'performance' [R/W] */
446         entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
447                                   S_IFREG | S_IRUGO,
448                                   acpi_device_dir(device));
449         if (entry){
450                 entry->proc_fops = &acpi_processor_perf_fops;
451                 entry->data = acpi_driver_data(device);
452                 entry->owner = THIS_MODULE;
453         }
454         return;
455 }
456
457 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
458 {
459         struct acpi_device *device = NULL;
460
461
462         if (acpi_bus_get_device(pr->handle, &device))
463                 return;
464
465         /* remove file 'performance' */
466         remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
467                           acpi_device_dir(device));
468
469         return;
470 }
471
472 #else
473 static void acpi_cpufreq_add_file(struct acpi_processor *pr)
474 {
475         return;
476 }
477 static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
478 {
479         return;
480 }
481 #endif                          /* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */
482
483 static int acpi_processor_get_psd(struct acpi_processor *pr)
484 {
485         int result = 0;
486         acpi_status status = AE_OK;
487         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
488         struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"};
489         struct acpi_buffer state = {0, NULL};
490         union acpi_object  *psd = NULL;
491         struct acpi_psd_package *pdomain;
492
493         status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer);
494         if (ACPI_FAILURE(status)) {
495                 return -ENODEV;
496         }
497
498         psd = buffer.pointer;
499         if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) {
500                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
501                 result = -EFAULT;
502                 goto end;
503         }
504
505         if (psd->package.count != 1) {
506                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
507                 result = -EFAULT;
508                 goto end;
509         }
510
511         pdomain = &(pr->performance->domain_info);
512
513         state.length = sizeof(struct acpi_psd_package);
514         state.pointer = pdomain;
515
516         status = acpi_extract_package(&(psd->package.elements[0]),
517                 &format, &state);
518         if (ACPI_FAILURE(status)) {
519                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSD data\n"));
520                 result = -EFAULT;
521                 goto end;
522         }
523
524         if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) {
525                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:num_entries\n"));
526                 result = -EFAULT;
527                 goto end;
528         }
529
530         if (pdomain->revision != ACPI_PSD_REV0_REVISION) {
531                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unknown _PSD:revision\n"));
532                 result = -EFAULT;
533                 goto end;
534         }
535
536 end:
537         kfree(buffer.pointer);
538         return result;
539 }
540
541 int acpi_processor_preregister_performance(
542                 struct acpi_processor_performance *performance)
543 {
544         int count, count_target;
545         int retval = 0;
546         unsigned int i, j;
547         cpumask_t covered_cpus;
548         struct acpi_processor *pr;
549         struct acpi_psd_package *pdomain;
550         struct acpi_processor *match_pr;
551         struct acpi_psd_package *match_pdomain;
552
553         mutex_lock(&performance_mutex);
554
555         retval = 0;
556
557         /* Call _PSD for all CPUs */
558         for_each_possible_cpu(i) {
559                 pr = processors[i];
560                 if (!pr) {
561                         /* Look only at processors in ACPI namespace */
562                         continue;
563                 }
564
565                 if (pr->performance) {
566                         retval = -EBUSY;
567                         continue;
568                 }
569
570                 if (!performance || !percpu_ptr(performance, i)) {
571                         retval = -EINVAL;
572                         continue;
573                 }
574
575                 pr->performance = percpu_ptr(performance, i);
576                 cpu_set(i, pr->performance->shared_cpu_map);
577                 if (acpi_processor_get_psd(pr)) {
578                         retval = -EINVAL;
579                         continue;
580                 }
581         }
582         if (retval)
583                 goto err_ret;
584
585         /*
586          * Now that we have _PSD data from all CPUs, lets setup P-state 
587          * domain info.
588          */
589         for_each_possible_cpu(i) {
590                 pr = processors[i];
591                 if (!pr)
592                         continue;
593
594                 /* Basic validity check for domain info */
595                 pdomain = &(pr->performance->domain_info);
596                 if ((pdomain->revision != ACPI_PSD_REV0_REVISION) ||
597                     (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES)) {
598                         retval = -EINVAL;
599                         goto err_ret;
600                 }
601                 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
602                     pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
603                     pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
604                         retval = -EINVAL;
605                         goto err_ret;
606                 }
607         }
608
609         cpus_clear(covered_cpus);
610         for_each_possible_cpu(i) {
611                 pr = processors[i];
612                 if (!pr)
613                         continue;
614
615                 if (cpu_isset(i, covered_cpus))
616                         continue;
617
618                 pdomain = &(pr->performance->domain_info);
619                 cpu_set(i, pr->performance->shared_cpu_map);
620                 cpu_set(i, covered_cpus);
621                 if (pdomain->num_processors <= 1)
622                         continue;
623
624                 /* Validate the Domain info */
625                 count_target = pdomain->num_processors;
626                 count = 1;
627                 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
628                         pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
629                 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
630                         pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW;
631                 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
632                         pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY;
633
634                 for_each_possible_cpu(j) {
635                         if (i == j)
636                                 continue;
637
638                         match_pr = processors[j];
639                         if (!match_pr)
640                                 continue;
641
642                         match_pdomain = &(match_pr->performance->domain_info);
643                         if (match_pdomain->domain != pdomain->domain)
644                                 continue;
645
646                         /* Here i and j are in the same domain */
647
648                         if (match_pdomain->num_processors != count_target) {
649                                 retval = -EINVAL;
650                                 goto err_ret;
651                         }
652
653                         if (pdomain->coord_type != match_pdomain->coord_type) {
654                                 retval = -EINVAL;
655                                 goto err_ret;
656                         }
657
658                         cpu_set(j, covered_cpus);
659                         cpu_set(j, pr->performance->shared_cpu_map);
660                         count++;
661                 }
662
663                 for_each_possible_cpu(j) {
664                         if (i == j)
665                                 continue;
666
667                         match_pr = processors[j];
668                         if (!match_pr)
669                                 continue;
670
671                         match_pdomain = &(match_pr->performance->domain_info);
672                         if (match_pdomain->domain != pdomain->domain)
673                                 continue;
674
675                         match_pr->performance->shared_type = 
676                                         pr->performance->shared_type;
677                         match_pr->performance->shared_cpu_map =
678                                 pr->performance->shared_cpu_map;
679                 }
680         }
681
682 err_ret:
683         for_each_possible_cpu(i) {
684                 pr = processors[i];
685                 if (!pr || !pr->performance)
686                         continue;
687
688                 /* Assume no coordination on any error parsing domain info */
689                 if (retval) {
690                         cpus_clear(pr->performance->shared_cpu_map);
691                         cpu_set(i, pr->performance->shared_cpu_map);
692                         pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
693                 }
694                 pr->performance = NULL; /* Will be set for real in register */
695         }
696
697         mutex_unlock(&performance_mutex);
698         return retval;
699 }
700 EXPORT_SYMBOL(acpi_processor_preregister_performance);
701
702
703 int
704 acpi_processor_register_performance(struct acpi_processor_performance
705                                     *performance, unsigned int cpu)
706 {
707         struct acpi_processor *pr;
708
709
710         if (!(acpi_processor_ppc_status & PPC_REGISTERED))
711                 return -EINVAL;
712
713         mutex_lock(&performance_mutex);
714
715         pr = processors[cpu];
716         if (!pr) {
717                 mutex_unlock(&performance_mutex);
718                 return -ENODEV;
719         }
720
721         if (pr->performance) {
722                 mutex_unlock(&performance_mutex);
723                 return -EBUSY;
724         }
725
726         WARN_ON(!performance);
727
728         pr->performance = performance;
729
730         if (acpi_processor_get_performance_info(pr)) {
731                 pr->performance = NULL;
732                 mutex_unlock(&performance_mutex);
733                 return -EIO;
734         }
735
736         acpi_cpufreq_add_file(pr);
737
738         mutex_unlock(&performance_mutex);
739         return 0;
740 }
741
742 EXPORT_SYMBOL(acpi_processor_register_performance);
743
744 void
745 acpi_processor_unregister_performance(struct acpi_processor_performance
746                                       *performance, unsigned int cpu)
747 {
748         struct acpi_processor *pr;
749
750
751         mutex_lock(&performance_mutex);
752
753         pr = processors[cpu];
754         if (!pr) {
755                 mutex_unlock(&performance_mutex);
756                 return;
757         }
758
759         if (pr->performance)
760                 kfree(pr->performance->states);
761         pr->performance = NULL;
762
763         acpi_cpufreq_remove_file(pr);
764
765         mutex_unlock(&performance_mutex);
766
767         return;
768 }
769
770 EXPORT_SYMBOL(acpi_processor_unregister_performance);