2 * acpi-cpufreq.c - ACPI Processor P-States Driver
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) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or (at
14 * your option) any later version.
16 * This program is distributed in the hope that it will be useful, but
17 * WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * General Public License for more details.
21 * You should have received a copy of the GNU General Public License along
22 * with this program; if not, write to the Free Software Foundation, Inc.,
23 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/init.h>
31 #include <linux/smp.h>
32 #include <linux/sched.h>
33 #include <linux/cpufreq.h>
34 #include <linux/compiler.h>
35 #include <linux/dmi.h>
36 #include <trace/power.h>
38 #include <linux/acpi.h>
40 #include <linux/delay.h>
41 #include <linux/uaccess.h>
43 #include <acpi/processor.h>
46 #include <asm/processor.h>
47 #include <asm/cpufeature.h>
49 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \
52 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
53 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
54 MODULE_LICENSE("GPL");
57 UNDEFINED_CAPABLE
= 0,
58 SYSTEM_INTEL_MSR_CAPABLE
,
62 #define INTEL_MSR_RANGE (0xffff)
63 #define CPUID_6_ECX_APERFMPERF_CAPABILITY (0x1)
65 struct acpi_cpufreq_data
{
66 struct acpi_processor_performance
*acpi_data
;
67 struct cpufreq_frequency_table
*freq_table
;
69 unsigned int cpu_feature
;
72 static DEFINE_PER_CPU(struct acpi_cpufreq_data
*, drv_data
);
74 struct acpi_msr_data
{
75 u64 saved_aperf
, saved_mperf
;
78 static DEFINE_PER_CPU(struct acpi_msr_data
, msr_data
);
80 DEFINE_TRACE(power_mark
);
82 /* acpi_perf_data is a pointer to percpu data. */
83 static struct acpi_processor_performance
*acpi_perf_data
;
85 static struct cpufreq_driver acpi_cpufreq_driver
;
87 static unsigned int acpi_pstate_strict
;
89 static int check_est_cpu(unsigned int cpuid
)
91 struct cpuinfo_x86
*cpu
= &cpu_data(cpuid
);
93 if (cpu
->x86_vendor
!= X86_VENDOR_INTEL
||
94 !cpu_has(cpu
, X86_FEATURE_EST
))
100 static unsigned extract_io(u32 value
, struct acpi_cpufreq_data
*data
)
102 struct acpi_processor_performance
*perf
;
105 perf
= data
->acpi_data
;
107 for (i
= 0; i
< perf
->state_count
; i
++) {
108 if (value
== perf
->states
[i
].status
)
109 return data
->freq_table
[i
].frequency
;
114 static unsigned extract_msr(u32 msr
, struct acpi_cpufreq_data
*data
)
117 struct acpi_processor_performance
*perf
;
119 msr
&= INTEL_MSR_RANGE
;
120 perf
= data
->acpi_data
;
122 for (i
= 0; data
->freq_table
[i
].frequency
!= CPUFREQ_TABLE_END
; i
++) {
123 if (msr
== perf
->states
[data
->freq_table
[i
].index
].status
)
124 return data
->freq_table
[i
].frequency
;
126 return data
->freq_table
[0].frequency
;
129 static unsigned extract_freq(u32 val
, struct acpi_cpufreq_data
*data
)
131 switch (data
->cpu_feature
) {
132 case SYSTEM_INTEL_MSR_CAPABLE
:
133 return extract_msr(val
, data
);
134 case SYSTEM_IO_CAPABLE
:
135 return extract_io(val
, data
);
152 const struct cpumask
*mask
;
160 /* Called via smp_call_function_single(), on the target CPU */
161 static void do_drv_read(void *_cmd
)
163 struct drv_cmd
*cmd
= _cmd
;
167 case SYSTEM_INTEL_MSR_CAPABLE
:
168 rdmsr(cmd
->addr
.msr
.reg
, cmd
->val
, h
);
170 case SYSTEM_IO_CAPABLE
:
171 acpi_os_read_port((acpi_io_address
)cmd
->addr
.io
.port
,
173 (u32
)cmd
->addr
.io
.bit_width
);
180 /* Called via smp_call_function_many(), on the target CPUs */
181 static void do_drv_write(void *_cmd
)
183 struct drv_cmd
*cmd
= _cmd
;
187 case SYSTEM_INTEL_MSR_CAPABLE
:
188 rdmsr(cmd
->addr
.msr
.reg
, lo
, hi
);
189 lo
= (lo
& ~INTEL_MSR_RANGE
) | (cmd
->val
& INTEL_MSR_RANGE
);
190 wrmsr(cmd
->addr
.msr
.reg
, lo
, hi
);
192 case SYSTEM_IO_CAPABLE
:
193 acpi_os_write_port((acpi_io_address
)cmd
->addr
.io
.port
,
195 (u32
)cmd
->addr
.io
.bit_width
);
202 static void drv_read(struct drv_cmd
*cmd
)
206 smp_call_function_single(cpumask_any(cmd
->mask
), do_drv_read
, cmd
, 1);
209 static void drv_write(struct drv_cmd
*cmd
)
213 this_cpu
= get_cpu();
214 if (cpumask_test_cpu(this_cpu
, cmd
->mask
))
216 smp_call_function_many(cmd
->mask
, do_drv_write
, cmd
, 1);
220 static u32
get_cur_val(const struct cpumask
*mask
)
222 struct acpi_processor_performance
*perf
;
225 if (unlikely(cpumask_empty(mask
)))
228 switch (per_cpu(drv_data
, cpumask_first(mask
))->cpu_feature
) {
229 case SYSTEM_INTEL_MSR_CAPABLE
:
230 cmd
.type
= SYSTEM_INTEL_MSR_CAPABLE
;
231 cmd
.addr
.msr
.reg
= MSR_IA32_PERF_STATUS
;
233 case SYSTEM_IO_CAPABLE
:
234 cmd
.type
= SYSTEM_IO_CAPABLE
;
235 perf
= per_cpu(drv_data
, cpumask_first(mask
))->acpi_data
;
236 cmd
.addr
.io
.port
= perf
->control_register
.address
;
237 cmd
.addr
.io
.bit_width
= perf
->control_register
.bit_width
;
246 dprintk("get_cur_val = %u\n", cmd
.val
);
261 /* Called via smp_call_function_single(), on the target CPU */
262 static void read_measured_perf_ctrs(void *_cur
)
264 struct perf_pair
*cur
= _cur
;
266 rdmsr(MSR_IA32_APERF
, cur
->aperf
.split
.lo
, cur
->aperf
.split
.hi
);
267 rdmsr(MSR_IA32_MPERF
, cur
->mperf
.split
.lo
, cur
->mperf
.split
.hi
);
271 * Return the measured active (C0) frequency on this CPU since last call
274 * Return: Average CPU frequency in terms of max frequency (zero on error)
276 * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
277 * over a period of time, while CPU is in C0 state.
278 * IA32_MPERF counts at the rate of max advertised frequency
279 * IA32_APERF counts at the rate of actual CPU frequency
280 * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
281 * no meaning should be associated with absolute values of these MSRs.
283 static unsigned int get_measured_perf(struct cpufreq_policy
*policy
,
286 struct perf_pair readin
, cur
;
287 unsigned int perf_percent
;
290 if (smp_call_function_single(cpu
, read_measured_perf_ctrs
, &readin
, 1))
293 cur
.aperf
.whole
= readin
.aperf
.whole
-
294 per_cpu(msr_data
, cpu
).saved_aperf
;
295 cur
.mperf
.whole
= readin
.mperf
.whole
-
296 per_cpu(msr_data
, cpu
).saved_mperf
;
297 per_cpu(msr_data
, cpu
).saved_aperf
= readin
.aperf
.whole
;
298 per_cpu(msr_data
, cpu
).saved_mperf
= readin
.mperf
.whole
;
302 * We dont want to do 64 bit divide with 32 bit kernel
303 * Get an approximate value. Return failure in case we cannot get
304 * an approximate value.
306 if (unlikely(cur
.aperf
.split
.hi
|| cur
.mperf
.split
.hi
)) {
310 h
= max_t(u32
, cur
.aperf
.split
.hi
, cur
.mperf
.split
.hi
);
311 shift_count
= fls(h
);
313 cur
.aperf
.whole
>>= shift_count
;
314 cur
.mperf
.whole
>>= shift_count
;
317 if (((unsigned long)(-1) / 100) < cur
.aperf
.split
.lo
) {
319 cur
.aperf
.split
.lo
>>= shift_count
;
320 cur
.mperf
.split
.lo
>>= shift_count
;
323 if (cur
.aperf
.split
.lo
&& cur
.mperf
.split
.lo
)
324 perf_percent
= (cur
.aperf
.split
.lo
* 100) / cur
.mperf
.split
.lo
;
329 if (unlikely(((unsigned long)(-1) / 100) < cur
.aperf
.whole
)) {
331 cur
.aperf
.whole
>>= shift_count
;
332 cur
.mperf
.whole
>>= shift_count
;
335 if (cur
.aperf
.whole
&& cur
.mperf
.whole
)
336 perf_percent
= (cur
.aperf
.whole
* 100) / cur
.mperf
.whole
;
342 retval
= (policy
->cpuinfo
.max_freq
* perf_percent
) / 100;
347 static unsigned int get_cur_freq_on_cpu(unsigned int cpu
)
349 struct acpi_cpufreq_data
*data
= per_cpu(drv_data
, cpu
);
351 unsigned int cached_freq
;
353 dprintk("get_cur_freq_on_cpu (%d)\n", cpu
);
355 if (unlikely(data
== NULL
||
356 data
->acpi_data
== NULL
|| data
->freq_table
== NULL
)) {
360 cached_freq
= data
->freq_table
[data
->acpi_data
->state
].frequency
;
361 freq
= extract_freq(get_cur_val(cpumask_of(cpu
)), data
);
362 if (freq
!= cached_freq
) {
364 * The dreaded BIOS frequency change behind our back.
365 * Force set the frequency on next target call.
370 dprintk("cur freq = %u\n", freq
);
375 static unsigned int check_freqs(const struct cpumask
*mask
, unsigned int freq
,
376 struct acpi_cpufreq_data
*data
)
378 unsigned int cur_freq
;
381 for (i
= 0; i
< 100; i
++) {
382 cur_freq
= extract_freq(get_cur_val(mask
), data
);
383 if (cur_freq
== freq
)
390 static int acpi_cpufreq_target(struct cpufreq_policy
*policy
,
391 unsigned int target_freq
, unsigned int relation
)
393 struct acpi_cpufreq_data
*data
= per_cpu(drv_data
, policy
->cpu
);
394 struct acpi_processor_performance
*perf
;
395 struct cpufreq_freqs freqs
;
397 unsigned int next_state
= 0; /* Index into freq_table */
398 unsigned int next_perf_state
= 0; /* Index into perf table */
401 struct power_trace it
;
403 dprintk("acpi_cpufreq_target %d (%d)\n", target_freq
, policy
->cpu
);
405 if (unlikely(data
== NULL
||
406 data
->acpi_data
== NULL
|| data
->freq_table
== NULL
)) {
410 perf
= data
->acpi_data
;
411 result
= cpufreq_frequency_table_target(policy
,
414 relation
, &next_state
);
415 if (unlikely(result
)) {
420 next_perf_state
= data
->freq_table
[next_state
].index
;
421 if (perf
->state
== next_perf_state
) {
422 if (unlikely(data
->resume
)) {
423 dprintk("Called after resume, resetting to P%d\n",
427 dprintk("Already at target state (P%d)\n",
433 trace_power_mark(&it
, POWER_PSTATE
, next_perf_state
);
435 switch (data
->cpu_feature
) {
436 case SYSTEM_INTEL_MSR_CAPABLE
:
437 cmd
.type
= SYSTEM_INTEL_MSR_CAPABLE
;
438 cmd
.addr
.msr
.reg
= MSR_IA32_PERF_CTL
;
439 cmd
.val
= (u32
) perf
->states
[next_perf_state
].control
;
441 case SYSTEM_IO_CAPABLE
:
442 cmd
.type
= SYSTEM_IO_CAPABLE
;
443 cmd
.addr
.io
.port
= perf
->control_register
.address
;
444 cmd
.addr
.io
.bit_width
= perf
->control_register
.bit_width
;
445 cmd
.val
= (u32
) perf
->states
[next_perf_state
].control
;
452 /* cpufreq holds the hotplug lock, so we are safe from here on */
453 if (policy
->shared_type
!= CPUFREQ_SHARED_TYPE_ANY
)
454 cmd
.mask
= policy
->cpus
;
456 cmd
.mask
= cpumask_of(policy
->cpu
);
458 freqs
.old
= perf
->states
[perf
->state
].core_frequency
* 1000;
459 freqs
.new = data
->freq_table
[next_state
].frequency
;
460 for_each_cpu(i
, cmd
.mask
) {
462 cpufreq_notify_transition(&freqs
, CPUFREQ_PRECHANGE
);
467 if (acpi_pstate_strict
) {
468 if (!check_freqs(cmd
.mask
, freqs
.new, data
)) {
469 dprintk("acpi_cpufreq_target failed (%d)\n",
476 for_each_cpu(i
, cmd
.mask
) {
478 cpufreq_notify_transition(&freqs
, CPUFREQ_POSTCHANGE
);
480 perf
->state
= next_perf_state
;
486 static int acpi_cpufreq_verify(struct cpufreq_policy
*policy
)
488 struct acpi_cpufreq_data
*data
= per_cpu(drv_data
, policy
->cpu
);
490 dprintk("acpi_cpufreq_verify\n");
492 return cpufreq_frequency_table_verify(policy
, data
->freq_table
);
496 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data
*data
, unsigned int cpu
)
498 struct acpi_processor_performance
*perf
= data
->acpi_data
;
501 /* search the closest match to cpu_khz */
504 unsigned long freqn
= perf
->states
[0].core_frequency
* 1000;
506 for (i
= 0; i
< (perf
->state_count
-1); i
++) {
508 freqn
= perf
->states
[i
+1].core_frequency
* 1000;
509 if ((2 * cpu_khz
) > (freqn
+ freq
)) {
514 perf
->state
= perf
->state_count
-1;
517 /* assume CPU is at P0... */
519 return perf
->states
[0].core_frequency
* 1000;
523 static void free_acpi_perf_data(void)
527 /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
528 for_each_possible_cpu(i
)
529 free_cpumask_var(per_cpu_ptr(acpi_perf_data
, i
)
531 free_percpu(acpi_perf_data
);
535 * acpi_cpufreq_early_init - initialize ACPI P-States library
537 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
538 * in order to determine correct frequency and voltage pairings. We can
539 * do _PDC and _PSD and find out the processor dependency for the
540 * actual init that will happen later...
542 static int __init
acpi_cpufreq_early_init(void)
545 dprintk("acpi_cpufreq_early_init\n");
547 acpi_perf_data
= alloc_percpu(struct acpi_processor_performance
);
548 if (!acpi_perf_data
) {
549 dprintk("Memory allocation error for acpi_perf_data.\n");
552 for_each_possible_cpu(i
) {
553 if (!zalloc_cpumask_var_node(
554 &per_cpu_ptr(acpi_perf_data
, i
)->shared_cpu_map
,
555 GFP_KERNEL
, cpu_to_node(i
))) {
557 /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
558 free_acpi_perf_data();
563 /* Do initialization in ACPI core */
564 acpi_processor_preregister_performance(acpi_perf_data
);
570 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
571 * or do it in BIOS firmware and won't inform about it to OS. If not
572 * detected, this has a side effect of making CPU run at a different speed
573 * than OS intended it to run at. Detect it and handle it cleanly.
575 static int bios_with_sw_any_bug
;
577 static int sw_any_bug_found(const struct dmi_system_id
*d
)
579 bios_with_sw_any_bug
= 1;
583 static const struct dmi_system_id sw_any_bug_dmi_table
[] = {
585 .callback
= sw_any_bug_found
,
586 .ident
= "Supermicro Server X6DLP",
588 DMI_MATCH(DMI_SYS_VENDOR
, "Supermicro"),
589 DMI_MATCH(DMI_BIOS_VERSION
, "080010"),
590 DMI_MATCH(DMI_PRODUCT_NAME
, "X6DLP"),
597 static int acpi_cpufreq_cpu_init(struct cpufreq_policy
*policy
)
600 unsigned int valid_states
= 0;
601 unsigned int cpu
= policy
->cpu
;
602 struct acpi_cpufreq_data
*data
;
603 unsigned int result
= 0;
604 struct cpuinfo_x86
*c
= &cpu_data(policy
->cpu
);
605 struct acpi_processor_performance
*perf
;
607 dprintk("acpi_cpufreq_cpu_init\n");
609 data
= kzalloc(sizeof(struct acpi_cpufreq_data
), GFP_KERNEL
);
613 data
->acpi_data
= per_cpu_ptr(acpi_perf_data
, cpu
);
614 per_cpu(drv_data
, cpu
) = data
;
616 if (cpu_has(c
, X86_FEATURE_CONSTANT_TSC
))
617 acpi_cpufreq_driver
.flags
|= CPUFREQ_CONST_LOOPS
;
619 result
= acpi_processor_register_performance(data
->acpi_data
, cpu
);
623 perf
= data
->acpi_data
;
624 policy
->shared_type
= perf
->shared_type
;
627 * Will let policy->cpus know about dependency only when software
628 * coordination is required.
630 if (policy
->shared_type
== CPUFREQ_SHARED_TYPE_ALL
||
631 policy
->shared_type
== CPUFREQ_SHARED_TYPE_ANY
) {
632 cpumask_copy(policy
->cpus
, perf
->shared_cpu_map
);
634 cpumask_copy(policy
->related_cpus
, perf
->shared_cpu_map
);
637 dmi_check_system(sw_any_bug_dmi_table
);
638 if (bios_with_sw_any_bug
&& cpumask_weight(policy
->cpus
) == 1) {
639 policy
->shared_type
= CPUFREQ_SHARED_TYPE_ALL
;
640 cpumask_copy(policy
->cpus
, cpu_core_mask(cpu
));
644 /* capability check */
645 if (perf
->state_count
<= 1) {
646 dprintk("No P-States\n");
651 if (perf
->control_register
.space_id
!= perf
->status_register
.space_id
) {
656 switch (perf
->control_register
.space_id
) {
657 case ACPI_ADR_SPACE_SYSTEM_IO
:
658 dprintk("SYSTEM IO addr space\n");
659 data
->cpu_feature
= SYSTEM_IO_CAPABLE
;
661 case ACPI_ADR_SPACE_FIXED_HARDWARE
:
662 dprintk("HARDWARE addr space\n");
663 if (!check_est_cpu(cpu
)) {
667 data
->cpu_feature
= SYSTEM_INTEL_MSR_CAPABLE
;
670 dprintk("Unknown addr space %d\n",
671 (u32
) (perf
->control_register
.space_id
));
676 data
->freq_table
= kmalloc(sizeof(struct cpufreq_frequency_table
) *
677 (perf
->state_count
+1), GFP_KERNEL
);
678 if (!data
->freq_table
) {
683 /* detect transition latency */
684 policy
->cpuinfo
.transition_latency
= 0;
685 for (i
= 0; i
< perf
->state_count
; i
++) {
686 if ((perf
->states
[i
].transition_latency
* 1000) >
687 policy
->cpuinfo
.transition_latency
)
688 policy
->cpuinfo
.transition_latency
=
689 perf
->states
[i
].transition_latency
* 1000;
692 /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
693 if (perf
->control_register
.space_id
== ACPI_ADR_SPACE_FIXED_HARDWARE
&&
694 policy
->cpuinfo
.transition_latency
> 20 * 1000) {
695 policy
->cpuinfo
.transition_latency
= 20 * 1000;
696 printk_once(KERN_INFO
697 "P-state transition latency capped at 20 uS\n");
701 for (i
= 0; i
< perf
->state_count
; i
++) {
702 if (i
> 0 && perf
->states
[i
].core_frequency
>=
703 data
->freq_table
[valid_states
-1].frequency
/ 1000)
706 data
->freq_table
[valid_states
].index
= i
;
707 data
->freq_table
[valid_states
].frequency
=
708 perf
->states
[i
].core_frequency
* 1000;
711 data
->freq_table
[valid_states
].frequency
= CPUFREQ_TABLE_END
;
714 result
= cpufreq_frequency_table_cpuinfo(policy
, data
->freq_table
);
718 if (perf
->states
[0].core_frequency
* 1000 != policy
->cpuinfo
.max_freq
)
719 printk(KERN_WARNING FW_WARN
"P-state 0 is not max freq\n");
721 switch (perf
->control_register
.space_id
) {
722 case ACPI_ADR_SPACE_SYSTEM_IO
:
723 /* Current speed is unknown and not detectable by IO port */
724 policy
->cur
= acpi_cpufreq_guess_freq(data
, policy
->cpu
);
726 case ACPI_ADR_SPACE_FIXED_HARDWARE
:
727 acpi_cpufreq_driver
.get
= get_cur_freq_on_cpu
;
728 policy
->cur
= get_cur_freq_on_cpu(cpu
);
734 /* notify BIOS that we exist */
735 acpi_processor_notify_smm(THIS_MODULE
);
737 /* Check for APERF/MPERF support in hardware */
738 if (c
->x86_vendor
== X86_VENDOR_INTEL
&& c
->cpuid_level
>= 6) {
741 if (ecx
& CPUID_6_ECX_APERFMPERF_CAPABILITY
)
742 acpi_cpufreq_driver
.getavg
= get_measured_perf
;
745 dprintk("CPU%u - ACPI performance management activated.\n", cpu
);
746 for (i
= 0; i
< perf
->state_count
; i
++)
747 dprintk(" %cP%d: %d MHz, %d mW, %d uS\n",
748 (i
== perf
->state
? '*' : ' '), i
,
749 (u32
) perf
->states
[i
].core_frequency
,
750 (u32
) perf
->states
[i
].power
,
751 (u32
) perf
->states
[i
].transition_latency
);
753 cpufreq_frequency_table_get_attr(data
->freq_table
, policy
->cpu
);
756 * the first call to ->target() should result in us actually
757 * writing something to the appropriate registers.
764 kfree(data
->freq_table
);
766 acpi_processor_unregister_performance(perf
, cpu
);
769 per_cpu(drv_data
, cpu
) = NULL
;
774 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy
*policy
)
776 struct acpi_cpufreq_data
*data
= per_cpu(drv_data
, policy
->cpu
);
778 dprintk("acpi_cpufreq_cpu_exit\n");
781 cpufreq_frequency_table_put_attr(policy
->cpu
);
782 per_cpu(drv_data
, policy
->cpu
) = NULL
;
783 acpi_processor_unregister_performance(data
->acpi_data
,
791 static int acpi_cpufreq_resume(struct cpufreq_policy
*policy
)
793 struct acpi_cpufreq_data
*data
= per_cpu(drv_data
, policy
->cpu
);
795 dprintk("acpi_cpufreq_resume\n");
802 static struct freq_attr
*acpi_cpufreq_attr
[] = {
803 &cpufreq_freq_attr_scaling_available_freqs
,
807 static struct cpufreq_driver acpi_cpufreq_driver
= {
808 .verify
= acpi_cpufreq_verify
,
809 .target
= acpi_cpufreq_target
,
810 .init
= acpi_cpufreq_cpu_init
,
811 .exit
= acpi_cpufreq_cpu_exit
,
812 .resume
= acpi_cpufreq_resume
,
813 .name
= "acpi-cpufreq",
814 .owner
= THIS_MODULE
,
815 .attr
= acpi_cpufreq_attr
,
818 static int __init
acpi_cpufreq_init(void)
825 dprintk("acpi_cpufreq_init\n");
827 ret
= acpi_cpufreq_early_init();
831 ret
= cpufreq_register_driver(&acpi_cpufreq_driver
);
833 free_acpi_perf_data();
838 static void __exit
acpi_cpufreq_exit(void)
840 dprintk("acpi_cpufreq_exit\n");
842 cpufreq_unregister_driver(&acpi_cpufreq_driver
);
844 free_percpu(acpi_perf_data
);
847 module_param(acpi_pstate_strict
, uint
, 0644);
848 MODULE_PARM_DESC(acpi_pstate_strict
,
849 "value 0 or non-zero. non-zero -> strict ACPI checks are "
850 "performed during frequency changes.");
852 late_initcall(acpi_cpufreq_init
);
853 module_exit(acpi_cpufreq_exit
);
855 MODULE_ALIAS("acpi");