s390/ptrace: get rid of long longs in psw_bits
[linux/fpc-iii.git] / drivers / acpi / processor_perflib.c
blobbb01dea39fdccfd50e0b61713b5ba983bb62285b
1 /*
2 * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
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
11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/cpufreq.h>
29 #include <linux/slab.h>
30 #include <linux/acpi.h>
31 #include <acpi/processor.h>
32 #ifdef CONFIG_X86
33 #include <asm/cpufeature.h>
34 #endif
36 #define PREFIX "ACPI: "
38 #define ACPI_PROCESSOR_CLASS "processor"
39 #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance"
40 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
41 ACPI_MODULE_NAME("processor_perflib");
43 static DEFINE_MUTEX(performance_mutex);
46 * _PPC support is implemented as a CPUfreq policy notifier:
47 * This means each time a CPUfreq driver registered also with
48 * the ACPI core is asked to change the speed policy, the maximum
49 * value is adjusted so that it is within the platform limit.
51 * Also, when a new platform limit value is detected, the CPUfreq
52 * policy is adjusted accordingly.
55 /* ignore_ppc:
56 * -1 -> cpufreq low level drivers not initialized -> _PSS, etc. not called yet
57 * ignore _PPC
58 * 0 -> cpufreq low level drivers initialized -> consider _PPC values
59 * 1 -> ignore _PPC totally -> forced by user through boot param
61 static int ignore_ppc = -1;
62 module_param(ignore_ppc, int, 0644);
63 MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \
64 "limited by BIOS, this should help");
66 #define PPC_REGISTERED 1
67 #define PPC_IN_USE 2
69 static int acpi_processor_ppc_status;
71 static int acpi_processor_ppc_notifier(struct notifier_block *nb,
72 unsigned long event, void *data)
74 struct cpufreq_policy *policy = data;
75 struct acpi_processor *pr;
76 unsigned int ppc = 0;
78 if (event == CPUFREQ_START && ignore_ppc <= 0) {
79 ignore_ppc = 0;
80 return 0;
83 if (ignore_ppc)
84 return 0;
86 if (event != CPUFREQ_ADJUST)
87 return 0;
89 mutex_lock(&performance_mutex);
91 pr = per_cpu(processors, policy->cpu);
92 if (!pr || !pr->performance)
93 goto out;
95 ppc = (unsigned int)pr->performance_platform_limit;
97 if (ppc >= pr->performance->state_count)
98 goto out;
100 cpufreq_verify_within_limits(policy, 0,
101 pr->performance->states[ppc].
102 core_frequency * 1000);
104 out:
105 mutex_unlock(&performance_mutex);
107 return 0;
110 static struct notifier_block acpi_ppc_notifier_block = {
111 .notifier_call = acpi_processor_ppc_notifier,
114 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
116 acpi_status status = 0;
117 unsigned long long ppc = 0;
120 if (!pr)
121 return -EINVAL;
124 * _PPC indicates the maximum state currently supported by the platform
125 * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
127 status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
129 if (status != AE_NOT_FOUND)
130 acpi_processor_ppc_status |= PPC_IN_USE;
132 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
133 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
134 return -ENODEV;
137 pr_debug("CPU %d: _PPC is %d - frequency %s limited\n", pr->id,
138 (int)ppc, ppc ? "" : "not");
140 pr->performance_platform_limit = (int)ppc;
142 return 0;
145 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
147 * acpi_processor_ppc_ost: Notify firmware the _PPC evaluation status
148 * @handle: ACPI processor handle
149 * @status: the status code of _PPC evaluation
150 * 0: success. OSPM is now using the performance state specificed.
151 * 1: failure. OSPM has not changed the number of P-states in use
153 static void acpi_processor_ppc_ost(acpi_handle handle, int status)
155 if (acpi_has_method(handle, "_OST"))
156 acpi_evaluate_ost(handle, ACPI_PROCESSOR_NOTIFY_PERFORMANCE,
157 status, NULL);
160 int acpi_processor_ppc_has_changed(struct acpi_processor *pr, int event_flag)
162 int ret;
164 if (ignore_ppc) {
166 * Only when it is notification event, the _OST object
167 * will be evaluated. Otherwise it is skipped.
169 if (event_flag)
170 acpi_processor_ppc_ost(pr->handle, 1);
171 return 0;
174 ret = acpi_processor_get_platform_limit(pr);
176 * Only when it is notification event, the _OST object
177 * will be evaluated. Otherwise it is skipped.
179 if (event_flag) {
180 if (ret < 0)
181 acpi_processor_ppc_ost(pr->handle, 1);
182 else
183 acpi_processor_ppc_ost(pr->handle, 0);
185 if (ret < 0)
186 return (ret);
187 else
188 return cpufreq_update_policy(pr->id);
191 int acpi_processor_get_bios_limit(int cpu, unsigned int *limit)
193 struct acpi_processor *pr;
195 pr = per_cpu(processors, cpu);
196 if (!pr || !pr->performance || !pr->performance->state_count)
197 return -ENODEV;
198 *limit = pr->performance->states[pr->performance_platform_limit].
199 core_frequency * 1000;
200 return 0;
202 EXPORT_SYMBOL(acpi_processor_get_bios_limit);
204 void acpi_processor_ppc_init(void)
206 if (!cpufreq_register_notifier
207 (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
208 acpi_processor_ppc_status |= PPC_REGISTERED;
209 else
210 printk(KERN_DEBUG
211 "Warning: Processor Platform Limit not supported.\n");
214 void acpi_processor_ppc_exit(void)
216 if (acpi_processor_ppc_status & PPC_REGISTERED)
217 cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
218 CPUFREQ_POLICY_NOTIFIER);
220 acpi_processor_ppc_status &= ~PPC_REGISTERED;
223 static int acpi_processor_get_performance_control(struct acpi_processor *pr)
225 int result = 0;
226 acpi_status status = 0;
227 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
228 union acpi_object *pct = NULL;
229 union acpi_object obj = { 0 };
232 status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
233 if (ACPI_FAILURE(status)) {
234 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT"));
235 return -ENODEV;
238 pct = (union acpi_object *)buffer.pointer;
239 if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
240 || (pct->package.count != 2)) {
241 printk(KERN_ERR PREFIX "Invalid _PCT data\n");
242 result = -EFAULT;
243 goto end;
247 * control_register
250 obj = pct->package.elements[0];
252 if ((obj.type != ACPI_TYPE_BUFFER)
253 || (obj.buffer.length < sizeof(struct acpi_pct_register))
254 || (obj.buffer.pointer == NULL)) {
255 printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n");
256 result = -EFAULT;
257 goto end;
259 memcpy(&pr->performance->control_register, obj.buffer.pointer,
260 sizeof(struct acpi_pct_register));
263 * status_register
266 obj = pct->package.elements[1];
268 if ((obj.type != ACPI_TYPE_BUFFER)
269 || (obj.buffer.length < sizeof(struct acpi_pct_register))
270 || (obj.buffer.pointer == NULL)) {
271 printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n");
272 result = -EFAULT;
273 goto end;
276 memcpy(&pr->performance->status_register, obj.buffer.pointer,
277 sizeof(struct acpi_pct_register));
279 end:
280 kfree(buffer.pointer);
282 return result;
285 #ifdef CONFIG_X86
287 * Some AMDs have 50MHz frequency multiples, but only provide 100MHz rounding
288 * in their ACPI data. Calculate the real values and fix up the _PSS data.
290 static void amd_fixup_frequency(struct acpi_processor_px *px, int i)
292 u32 hi, lo, fid, did;
293 int index = px->control & 0x00000007;
295 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
296 return;
298 if ((boot_cpu_data.x86 == 0x10 && boot_cpu_data.x86_model < 10)
299 || boot_cpu_data.x86 == 0x11) {
300 rdmsr(MSR_AMD_PSTATE_DEF_BASE + index, lo, hi);
302 * MSR C001_0064+:
303 * Bit 63: PstateEn. Read-write. If set, the P-state is valid.
305 if (!(hi & BIT(31)))
306 return;
308 fid = lo & 0x3f;
309 did = (lo >> 6) & 7;
310 if (boot_cpu_data.x86 == 0x10)
311 px->core_frequency = (100 * (fid + 0x10)) >> did;
312 else
313 px->core_frequency = (100 * (fid + 8)) >> did;
316 #else
317 static void amd_fixup_frequency(struct acpi_processor_px *px, int i) {};
318 #endif
320 static int acpi_processor_get_performance_states(struct acpi_processor *pr)
322 int result = 0;
323 acpi_status status = AE_OK;
324 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
325 struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" };
326 struct acpi_buffer state = { 0, NULL };
327 union acpi_object *pss = NULL;
328 int i;
329 int last_invalid = -1;
332 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
333 if (ACPI_FAILURE(status)) {
334 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS"));
335 return -ENODEV;
338 pss = buffer.pointer;
339 if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
340 printk(KERN_ERR PREFIX "Invalid _PSS data\n");
341 result = -EFAULT;
342 goto end;
345 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
346 pss->package.count));
348 pr->performance->state_count = pss->package.count;
349 pr->performance->states =
350 kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
351 GFP_KERNEL);
352 if (!pr->performance->states) {
353 result = -ENOMEM;
354 goto end;
357 for (i = 0; i < pr->performance->state_count; i++) {
359 struct acpi_processor_px *px = &(pr->performance->states[i]);
361 state.length = sizeof(struct acpi_processor_px);
362 state.pointer = px;
364 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
366 status = acpi_extract_package(&(pss->package.elements[i]),
367 &format, &state);
368 if (ACPI_FAILURE(status)) {
369 ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data"));
370 result = -EFAULT;
371 kfree(pr->performance->states);
372 goto end;
375 amd_fixup_frequency(px, i);
377 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
378 "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
380 (u32) px->core_frequency,
381 (u32) px->power,
382 (u32) px->transition_latency,
383 (u32) px->bus_master_latency,
384 (u32) px->control, (u32) px->status));
387 * Check that ACPI's u64 MHz will be valid as u32 KHz in cpufreq
389 if (!px->core_frequency ||
390 ((u32)(px->core_frequency * 1000) !=
391 (px->core_frequency * 1000))) {
392 printk(KERN_ERR FW_BUG PREFIX
393 "Invalid BIOS _PSS frequency found for processor %d: 0x%llx MHz\n",
394 pr->id, px->core_frequency);
395 if (last_invalid == -1)
396 last_invalid = i;
397 } else {
398 if (last_invalid != -1) {
400 * Copy this valid entry over last_invalid entry
402 memcpy(&(pr->performance->states[last_invalid]),
403 px, sizeof(struct acpi_processor_px));
404 ++last_invalid;
409 if (last_invalid == 0) {
410 printk(KERN_ERR FW_BUG PREFIX
411 "No valid BIOS _PSS frequency found for processor %d\n", pr->id);
412 result = -EFAULT;
413 kfree(pr->performance->states);
414 pr->performance->states = NULL;
417 if (last_invalid > 0)
418 pr->performance->state_count = last_invalid;
420 end:
421 kfree(buffer.pointer);
423 return result;
426 int acpi_processor_get_performance_info(struct acpi_processor *pr)
428 int result = 0;
430 if (!pr || !pr->performance || !pr->handle)
431 return -EINVAL;
433 if (!acpi_has_method(pr->handle, "_PCT")) {
434 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
435 "ACPI-based processor performance control unavailable\n"));
436 return -ENODEV;
439 result = acpi_processor_get_performance_control(pr);
440 if (result)
441 goto update_bios;
443 result = acpi_processor_get_performance_states(pr);
444 if (result)
445 goto update_bios;
447 /* We need to call _PPC once when cpufreq starts */
448 if (ignore_ppc != 1)
449 result = acpi_processor_get_platform_limit(pr);
451 return result;
454 * Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that
455 * the BIOS is older than the CPU and does not know its frequencies
457 update_bios:
458 #ifdef CONFIG_X86
459 if (acpi_has_method(pr->handle, "_PPC")) {
460 if(boot_cpu_has(X86_FEATURE_EST))
461 printk(KERN_WARNING FW_BUG "BIOS needs update for CPU "
462 "frequency support\n");
464 #endif
465 return result;
467 EXPORT_SYMBOL_GPL(acpi_processor_get_performance_info);
468 int acpi_processor_notify_smm(struct module *calling_module)
470 acpi_status status;
471 static int is_done = 0;
474 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
475 return -EBUSY;
477 if (!try_module_get(calling_module))
478 return -EINVAL;
480 /* is_done is set to negative if an error occurred,
481 * and to postitive if _no_ error occurred, but SMM
482 * was already notified. This avoids double notification
483 * which might lead to unexpected results...
485 if (is_done > 0) {
486 module_put(calling_module);
487 return 0;
488 } else if (is_done < 0) {
489 module_put(calling_module);
490 return is_done;
493 is_done = -EIO;
495 /* Can't write pstate_control to smi_command if either value is zero */
496 if ((!acpi_gbl_FADT.smi_command) || (!acpi_gbl_FADT.pstate_control)) {
497 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n"));
498 module_put(calling_module);
499 return 0;
502 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
503 "Writing pstate_control [0x%x] to smi_command [0x%x]\n",
504 acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command));
506 status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
507 (u32) acpi_gbl_FADT.pstate_control, 8);
508 if (ACPI_FAILURE(status)) {
509 ACPI_EXCEPTION((AE_INFO, status,
510 "Failed to write pstate_control [0x%x] to "
511 "smi_command [0x%x]", acpi_gbl_FADT.pstate_control,
512 acpi_gbl_FADT.smi_command));
513 module_put(calling_module);
514 return status;
517 /* Success. If there's no _PPC, we need to fear nothing, so
518 * we can allow the cpufreq driver to be rmmod'ed. */
519 is_done = 1;
521 if (!(acpi_processor_ppc_status & PPC_IN_USE))
522 module_put(calling_module);
524 return 0;
527 EXPORT_SYMBOL(acpi_processor_notify_smm);
529 static int acpi_processor_get_psd(struct acpi_processor *pr)
531 int result = 0;
532 acpi_status status = AE_OK;
533 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
534 struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"};
535 struct acpi_buffer state = {0, NULL};
536 union acpi_object *psd = NULL;
537 struct acpi_psd_package *pdomain;
539 status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer);
540 if (ACPI_FAILURE(status)) {
541 return -ENODEV;
544 psd = buffer.pointer;
545 if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) {
546 printk(KERN_ERR PREFIX "Invalid _PSD data\n");
547 result = -EFAULT;
548 goto end;
551 if (psd->package.count != 1) {
552 printk(KERN_ERR PREFIX "Invalid _PSD data\n");
553 result = -EFAULT;
554 goto end;
557 pdomain = &(pr->performance->domain_info);
559 state.length = sizeof(struct acpi_psd_package);
560 state.pointer = pdomain;
562 status = acpi_extract_package(&(psd->package.elements[0]),
563 &format, &state);
564 if (ACPI_FAILURE(status)) {
565 printk(KERN_ERR PREFIX "Invalid _PSD data\n");
566 result = -EFAULT;
567 goto end;
570 if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) {
571 printk(KERN_ERR PREFIX "Unknown _PSD:num_entries\n");
572 result = -EFAULT;
573 goto end;
576 if (pdomain->revision != ACPI_PSD_REV0_REVISION) {
577 printk(KERN_ERR PREFIX "Unknown _PSD:revision\n");
578 result = -EFAULT;
579 goto end;
582 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
583 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
584 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
585 printk(KERN_ERR PREFIX "Invalid _PSD:coord_type\n");
586 result = -EFAULT;
587 goto end;
589 end:
590 kfree(buffer.pointer);
591 return result;
594 int acpi_processor_preregister_performance(
595 struct acpi_processor_performance __percpu *performance)
597 int count_target;
598 int retval = 0;
599 unsigned int i, j;
600 cpumask_var_t covered_cpus;
601 struct acpi_processor *pr;
602 struct acpi_psd_package *pdomain;
603 struct acpi_processor *match_pr;
604 struct acpi_psd_package *match_pdomain;
606 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
607 return -ENOMEM;
609 mutex_lock(&performance_mutex);
612 * Check if another driver has already registered, and abort before
613 * changing pr->performance if it has. Check input data as well.
615 for_each_possible_cpu(i) {
616 pr = per_cpu(processors, i);
617 if (!pr) {
618 /* Look only at processors in ACPI namespace */
619 continue;
622 if (pr->performance) {
623 retval = -EBUSY;
624 goto err_out;
627 if (!performance || !per_cpu_ptr(performance, i)) {
628 retval = -EINVAL;
629 goto err_out;
633 /* Call _PSD for all CPUs */
634 for_each_possible_cpu(i) {
635 pr = per_cpu(processors, i);
636 if (!pr)
637 continue;
639 pr->performance = per_cpu_ptr(performance, i);
640 cpumask_set_cpu(i, pr->performance->shared_cpu_map);
641 if (acpi_processor_get_psd(pr)) {
642 retval = -EINVAL;
643 continue;
646 if (retval)
647 goto err_ret;
650 * Now that we have _PSD data from all CPUs, lets setup P-state
651 * domain info.
653 for_each_possible_cpu(i) {
654 pr = per_cpu(processors, i);
655 if (!pr)
656 continue;
658 if (cpumask_test_cpu(i, covered_cpus))
659 continue;
661 pdomain = &(pr->performance->domain_info);
662 cpumask_set_cpu(i, pr->performance->shared_cpu_map);
663 cpumask_set_cpu(i, covered_cpus);
664 if (pdomain->num_processors <= 1)
665 continue;
667 /* Validate the Domain info */
668 count_target = pdomain->num_processors;
669 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
670 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
671 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
672 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW;
673 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
674 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY;
676 for_each_possible_cpu(j) {
677 if (i == j)
678 continue;
680 match_pr = per_cpu(processors, j);
681 if (!match_pr)
682 continue;
684 match_pdomain = &(match_pr->performance->domain_info);
685 if (match_pdomain->domain != pdomain->domain)
686 continue;
688 /* Here i and j are in the same domain */
690 if (match_pdomain->num_processors != count_target) {
691 retval = -EINVAL;
692 goto err_ret;
695 if (pdomain->coord_type != match_pdomain->coord_type) {
696 retval = -EINVAL;
697 goto err_ret;
700 cpumask_set_cpu(j, covered_cpus);
701 cpumask_set_cpu(j, pr->performance->shared_cpu_map);
704 for_each_possible_cpu(j) {
705 if (i == j)
706 continue;
708 match_pr = per_cpu(processors, j);
709 if (!match_pr)
710 continue;
712 match_pdomain = &(match_pr->performance->domain_info);
713 if (match_pdomain->domain != pdomain->domain)
714 continue;
716 match_pr->performance->shared_type =
717 pr->performance->shared_type;
718 cpumask_copy(match_pr->performance->shared_cpu_map,
719 pr->performance->shared_cpu_map);
723 err_ret:
724 for_each_possible_cpu(i) {
725 pr = per_cpu(processors, i);
726 if (!pr || !pr->performance)
727 continue;
729 /* Assume no coordination on any error parsing domain info */
730 if (retval) {
731 cpumask_clear(pr->performance->shared_cpu_map);
732 cpumask_set_cpu(i, pr->performance->shared_cpu_map);
733 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL;
735 pr->performance = NULL; /* Will be set for real in register */
738 err_out:
739 mutex_unlock(&performance_mutex);
740 free_cpumask_var(covered_cpus);
741 return retval;
743 EXPORT_SYMBOL(acpi_processor_preregister_performance);
746 acpi_processor_register_performance(struct acpi_processor_performance
747 *performance, unsigned int cpu)
749 struct acpi_processor *pr;
751 if (!(acpi_processor_ppc_status & PPC_REGISTERED))
752 return -EINVAL;
754 mutex_lock(&performance_mutex);
756 pr = per_cpu(processors, cpu);
757 if (!pr) {
758 mutex_unlock(&performance_mutex);
759 return -ENODEV;
762 if (pr->performance) {
763 mutex_unlock(&performance_mutex);
764 return -EBUSY;
767 WARN_ON(!performance);
769 pr->performance = performance;
771 if (acpi_processor_get_performance_info(pr)) {
772 pr->performance = NULL;
773 mutex_unlock(&performance_mutex);
774 return -EIO;
777 mutex_unlock(&performance_mutex);
778 return 0;
781 EXPORT_SYMBOL(acpi_processor_register_performance);
783 void acpi_processor_unregister_performance(unsigned int cpu)
785 struct acpi_processor *pr;
787 mutex_lock(&performance_mutex);
789 pr = per_cpu(processors, cpu);
790 if (!pr) {
791 mutex_unlock(&performance_mutex);
792 return;
795 if (pr->performance)
796 kfree(pr->performance->states);
797 pr->performance = NULL;
799 mutex_unlock(&performance_mutex);
801 return;
804 EXPORT_SYMBOL(acpi_processor_unregister_performance);