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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
37#include <linux/acpi.h>
38#include <acpi/processor.h>
39
40#include <asm/io.h>
41#include <asm/msr.h>
42#include <asm/processor.h>
43#include <asm/cpufeature.h>
44#include <asm/delay.h>
45#include <asm/uaccess.h>
46
47#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "acpi-cpufreq", msg)
48
49MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
50MODULE_DESCRIPTION("ACPI Processor P-States Driver");
51MODULE_LICENSE("GPL");
52
53enum {
54 UNDEFINED_CAPABLE = 0,
55 SYSTEM_INTEL_MSR_CAPABLE,
56 SYSTEM_IO_CAPABLE,
57};
58
59#define INTEL_MSR_RANGE (0xffff)
60#define CPUID_6_ECX_APERFMPERF_CAPABILITY (0x1)
61
62struct acpi_cpufreq_data {
63 struct acpi_processor_performance *acpi_data;
64 struct cpufreq_frequency_table *freq_table;
65 unsigned int max_freq;
66 unsigned int resume;
67 unsigned int cpu_feature;
68};
69
70static DEFINE_PER_CPU(struct acpi_cpufreq_data *, drv_data);
71
72
73static struct acpi_processor_performance *acpi_perf_data;
74
75static struct cpufreq_driver acpi_cpufreq_driver;
76
77static unsigned int acpi_pstate_strict;
78
79static int check_est_cpu(unsigned int cpuid)
80{
81 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
82
83 if (cpu->x86_vendor != X86_VENDOR_INTEL ||
84 !cpu_has(cpu, X86_FEATURE_EST))
85 return 0;
86
87 return 1;
88}
89
90static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
91{
92 struct acpi_processor_performance *perf;
93 int i;
94
95 perf = data->acpi_data;
96
97 for (i=0; i<perf->state_count; i++) {
98 if (value == perf->states[i].status)
99 return data->freq_table[i].frequency;
100 }
101 return 0;
102}
103
104static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
105{
106 int i;
107 struct acpi_processor_performance *perf;
108
109 msr &= INTEL_MSR_RANGE;
110 perf = data->acpi_data;
111
112 for (i=0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
113 if (msr == perf->states[data->freq_table[i].index].status)
114 return data->freq_table[i].frequency;
115 }
116 return data->freq_table[0].frequency;
117}
118
119static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
120{
121 switch (data->cpu_feature) {
122 case SYSTEM_INTEL_MSR_CAPABLE:
123 return extract_msr(val, data);
124 case SYSTEM_IO_CAPABLE:
125 return extract_io(val, data);
126 default:
127 return 0;
128 }
129}
130
131struct msr_addr {
132 u32 reg;
133};
134
135struct io_addr {
136 u16 port;
137 u8 bit_width;
138};
139
140typedef union {
141 struct msr_addr msr;
142 struct io_addr io;
143} drv_addr_union;
144
145struct drv_cmd {
146 unsigned int type;
147 cpumask_t mask;
148 drv_addr_union addr;
149 u32 val;
150};
151
152static void do_drv_read(struct drv_cmd *cmd)
153{
154 u32 h;
155
156 switch (cmd->type) {
157 case SYSTEM_INTEL_MSR_CAPABLE:
158 rdmsr(cmd->addr.msr.reg, cmd->val, h);
159 break;
160 case SYSTEM_IO_CAPABLE:
161 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
162 &cmd->val,
163 (u32)cmd->addr.io.bit_width);
164 break;
165 default:
166 break;
167 }
168}
169
170static void do_drv_write(struct drv_cmd *cmd)
171{
172 u32 lo, hi;
173
174 switch (cmd->type) {
175 case SYSTEM_INTEL_MSR_CAPABLE:
176 rdmsr(cmd->addr.msr.reg, lo, hi);
177 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
178 wrmsr(cmd->addr.msr.reg, lo, hi);
179 break;
180 case SYSTEM_IO_CAPABLE:
181 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
182 cmd->val,
183 (u32)cmd->addr.io.bit_width);
184 break;
185 default:
186 break;
187 }
188}
189
190static void drv_read(struct drv_cmd *cmd)
191{
192 cpumask_t saved_mask = current->cpus_allowed;
193 cmd->val = 0;
194
195 set_cpus_allowed_ptr(current, &cmd->mask);
196 do_drv_read(cmd);
197 set_cpus_allowed_ptr(current, &saved_mask);
198}
199
200static void drv_write(struct drv_cmd *cmd)
201{
202 cpumask_t saved_mask = current->cpus_allowed;
203 unsigned int i;
204
205 for_each_cpu_mask_nr(i, cmd->mask) {
206 set_cpus_allowed_ptr(current, &cpumask_of_cpu(i));
207 do_drv_write(cmd);
208 }
209
210 set_cpus_allowed_ptr(current, &saved_mask);
211 return;
212}
213
214static u32 get_cur_val(const cpumask_t *mask)
215{
216 struct acpi_processor_performance *perf;
217 struct drv_cmd cmd;
218
219 if (unlikely(cpus_empty(*mask)))
220 return 0;
221
222 switch (per_cpu(drv_data, first_cpu(*mask))->cpu_feature) {
223 case SYSTEM_INTEL_MSR_CAPABLE:
224 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
225 cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
226 break;
227 case SYSTEM_IO_CAPABLE:
228 cmd.type = SYSTEM_IO_CAPABLE;
229 perf = per_cpu(drv_data, first_cpu(*mask))->acpi_data;
230 cmd.addr.io.port = perf->control_register.address;
231 cmd.addr.io.bit_width = perf->control_register.bit_width;
232 break;
233 default:
234 return 0;
235 }
236
237 cmd.mask = *mask;
238
239 drv_read(&cmd);
240
241 dprintk("get_cur_val = %u\n", cmd.val);
242
243 return cmd.val;
244}
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259static unsigned int get_measured_perf(struct cpufreq_policy *policy,
260 unsigned int cpu)
261{
262 union {
263 struct {
264 u32 lo;
265 u32 hi;
266 } split;
267 u64 whole;
268 } aperf_cur, mperf_cur;
269
270 cpumask_t saved_mask;
271 unsigned int perf_percent;
272 unsigned int retval;
273
274 saved_mask = current->cpus_allowed;
275 set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
276 if (get_cpu() != cpu) {
277
278 put_cpu();
279 return 0;
280 }
281
282 rdmsr(MSR_IA32_APERF, aperf_cur.split.lo, aperf_cur.split.hi);
283 rdmsr(MSR_IA32_MPERF, mperf_cur.split.lo, mperf_cur.split.hi);
284
285 wrmsr(MSR_IA32_APERF, 0,0);
286 wrmsr(MSR_IA32_MPERF, 0,0);
287
288#ifdef __i386__
289
290
291
292
293
294 if (unlikely(aperf_cur.split.hi || mperf_cur.split.hi)) {
295 int shift_count;
296 u32 h;
297
298 h = max_t(u32, aperf_cur.split.hi, mperf_cur.split.hi);
299 shift_count = fls(h);
300
301 aperf_cur.whole >>= shift_count;
302 mperf_cur.whole >>= shift_count;
303 }
304
305 if (((unsigned long)(-1) / 100) < aperf_cur.split.lo) {
306 int shift_count = 7;
307 aperf_cur.split.lo >>= shift_count;
308 mperf_cur.split.lo >>= shift_count;
309 }
310
311 if (aperf_cur.split.lo && mperf_cur.split.lo)
312 perf_percent = (aperf_cur.split.lo * 100) / mperf_cur.split.lo;
313 else
314 perf_percent = 0;
315
316#else
317 if (unlikely(((unsigned long)(-1) / 100) < aperf_cur.whole)) {
318 int shift_count = 7;
319 aperf_cur.whole >>= shift_count;
320 mperf_cur.whole >>= shift_count;
321 }
322
323 if (aperf_cur.whole && mperf_cur.whole)
324 perf_percent = (aperf_cur.whole * 100) / mperf_cur.whole;
325 else
326 perf_percent = 0;
327
328#endif
329
330 retval = per_cpu(drv_data, policy->cpu)->max_freq * perf_percent / 100;
331
332 put_cpu();
333 set_cpus_allowed_ptr(current, &saved_mask);
334
335 dprintk("cpu %d: performance percent %d\n", cpu, perf_percent);
336 return retval;
337}
338
339static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
340{
341 struct acpi_cpufreq_data *data = per_cpu(drv_data, cpu);
342 unsigned int freq;
343 unsigned int cached_freq;
344
345 dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
346
347 if (unlikely(data == NULL ||
348 data->acpi_data == NULL || data->freq_table == NULL)) {
349 return 0;
350 }
351
352 cached_freq = data->freq_table[data->acpi_data->state].frequency;
353 freq = extract_freq(get_cur_val(&cpumask_of_cpu(cpu)), data);
354 if (freq != cached_freq) {
355
356
357
358
359 data->resume = 1;
360 }
361
362 dprintk("cur freq = %u\n", freq);
363
364 return freq;
365}
366
367static unsigned int check_freqs(const cpumask_t *mask, unsigned int freq,
368 struct acpi_cpufreq_data *data)
369{
370 unsigned int cur_freq;
371 unsigned int i;
372
373 for (i=0; i<100; i++) {
374 cur_freq = extract_freq(get_cur_val(mask), data);
375 if (cur_freq == freq)
376 return 1;
377 udelay(10);
378 }
379 return 0;
380}
381
382static int acpi_cpufreq_target(struct cpufreq_policy *policy,
383 unsigned int target_freq, unsigned int relation)
384{
385 struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
386 struct acpi_processor_performance *perf;
387 struct cpufreq_freqs freqs;
388 cpumask_t online_policy_cpus;
389 struct drv_cmd cmd;
390 unsigned int next_state = 0;
391 unsigned int next_perf_state = 0;
392 unsigned int i;
393 int result = 0;
394
395 dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
396
397 if (unlikely(data == NULL ||
398 data->acpi_data == NULL || data->freq_table == NULL)) {
399 return -ENODEV;
400 }
401
402 perf = data->acpi_data;
403 result = cpufreq_frequency_table_target(policy,
404 data->freq_table,
405 target_freq,
406 relation, &next_state);
407 if (unlikely(result))
408 return -ENODEV;
409
410#ifdef CONFIG_HOTPLUG_CPU
411
412 cpus_and(online_policy_cpus, cpu_online_map, policy->cpus);
413#else
414 online_policy_cpus = policy->cpus;
415#endif
416
417 next_perf_state = data->freq_table[next_state].index;
418 if (perf->state == next_perf_state) {
419 if (unlikely(data->resume)) {
420 dprintk("Called after resume, resetting to P%d\n",
421 next_perf_state);
422 data->resume = 0;
423 } else {
424 dprintk("Already at target state (P%d)\n",
425 next_perf_state);
426 return 0;
427 }
428 }
429
430 switch (data->cpu_feature) {
431 case SYSTEM_INTEL_MSR_CAPABLE:
432 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
433 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
434 cmd.val = (u32) perf->states[next_perf_state].control;
435 break;
436 case SYSTEM_IO_CAPABLE:
437 cmd.type = SYSTEM_IO_CAPABLE;
438 cmd.addr.io.port = perf->control_register.address;
439 cmd.addr.io.bit_width = perf->control_register.bit_width;
440 cmd.val = (u32) perf->states[next_perf_state].control;
441 break;
442 default:
443 return -ENODEV;
444 }
445
446 cpus_clear(cmd.mask);
447
448 if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
449 cmd.mask = online_policy_cpus;
450 else
451 cpu_set(policy->cpu, cmd.mask);
452
453 freqs.old = perf->states[perf->state].core_frequency * 1000;
454 freqs.new = data->freq_table[next_state].frequency;
455 for_each_cpu_mask_nr(i, cmd.mask) {
456 freqs.cpu = i;
457 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
458 }
459
460 drv_write(&cmd);
461
462 if (acpi_pstate_strict) {
463 if (!check_freqs(&cmd.mask, freqs.new, data)) {
464 dprintk("acpi_cpufreq_target failed (%d)\n",
465 policy->cpu);
466 return -EAGAIN;
467 }
468 }
469
470 for_each_cpu_mask_nr(i, cmd.mask) {
471 freqs.cpu = i;
472 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
473 }
474 perf->state = next_perf_state;
475
476 return result;
477}
478
479static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
480{
481 struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
482
483 dprintk("acpi_cpufreq_verify\n");
484
485 return cpufreq_frequency_table_verify(policy, data->freq_table);
486}
487
488static unsigned long
489acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
490{
491 struct acpi_processor_performance *perf = data->acpi_data;
492
493 if (cpu_khz) {
494
495 unsigned int i;
496 unsigned long freq;
497 unsigned long freqn = perf->states[0].core_frequency * 1000;
498
499 for (i=0; i<(perf->state_count-1); i++) {
500 freq = freqn;
501 freqn = perf->states[i+1].core_frequency * 1000;
502 if ((2 * cpu_khz) > (freqn + freq)) {
503 perf->state = i;
504 return freq;
505 }
506 }
507 perf->state = perf->state_count-1;
508 return freqn;
509 } else {
510
511 perf->state = 0;
512 return perf->states[0].core_frequency * 1000;
513 }
514}
515
516
517
518
519
520
521
522
523
524static int __init acpi_cpufreq_early_init(void)
525{
526 dprintk("acpi_cpufreq_early_init\n");
527
528 acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
529 if (!acpi_perf_data) {
530 dprintk("Memory allocation error for acpi_perf_data.\n");
531 return -ENOMEM;
532 }
533
534
535 acpi_processor_preregister_performance(acpi_perf_data);
536 return 0;
537}
538
539#ifdef CONFIG_SMP
540
541
542
543
544
545
546static int bios_with_sw_any_bug;
547
548static int sw_any_bug_found(const struct dmi_system_id *d)
549{
550 bios_with_sw_any_bug = 1;
551 return 0;
552}
553
554static const struct dmi_system_id sw_any_bug_dmi_table[] = {
555 {
556 .callback = sw_any_bug_found,
557 .ident = "Supermicro Server X6DLP",
558 .matches = {
559 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
560 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
561 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
562 },
563 },
564 { }
565};
566#endif
567
568static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
569{
570 unsigned int i;
571 unsigned int valid_states = 0;
572 unsigned int cpu = policy->cpu;
573 struct acpi_cpufreq_data *data;
574 unsigned int result = 0;
575 struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
576 struct acpi_processor_performance *perf;
577
578 dprintk("acpi_cpufreq_cpu_init\n");
579
580 data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
581 if (!data)
582 return -ENOMEM;
583
584 data->acpi_data = percpu_ptr(acpi_perf_data, cpu);
585 per_cpu(drv_data, cpu) = data;
586
587 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
588 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
589
590 result = acpi_processor_register_performance(data->acpi_data, cpu);
591 if (result)
592 goto err_free;
593
594 perf = data->acpi_data;
595 policy->shared_type = perf->shared_type;
596
597
598
599
600
601 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
602 policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
603 policy->cpus = perf->shared_cpu_map;
604 }
605 policy->related_cpus = perf->shared_cpu_map;
606
607#ifdef CONFIG_SMP
608 dmi_check_system(sw_any_bug_dmi_table);
609 if (bios_with_sw_any_bug && cpus_weight(policy->cpus) == 1) {
610 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
611 policy->cpus = per_cpu(cpu_core_map, cpu);
612 }
613#endif
614
615
616 if (perf->state_count <= 1) {
617 dprintk("No P-States\n");
618 result = -ENODEV;
619 goto err_unreg;
620 }
621
622 if (perf->control_register.space_id != perf->status_register.space_id) {
623 result = -ENODEV;
624 goto err_unreg;
625 }
626
627 switch (perf->control_register.space_id) {
628 case ACPI_ADR_SPACE_SYSTEM_IO:
629 dprintk("SYSTEM IO addr space\n");
630 data->cpu_feature = SYSTEM_IO_CAPABLE;
631 break;
632 case ACPI_ADR_SPACE_FIXED_HARDWARE:
633 dprintk("HARDWARE addr space\n");
634 if (!check_est_cpu(cpu)) {
635 result = -ENODEV;
636 goto err_unreg;
637 }
638 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
639 break;
640 default:
641 dprintk("Unknown addr space %d\n",
642 (u32) (perf->control_register.space_id));
643 result = -ENODEV;
644 goto err_unreg;
645 }
646
647 data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
648 (perf->state_count+1), GFP_KERNEL);
649 if (!data->freq_table) {
650 result = -ENOMEM;
651 goto err_unreg;
652 }
653
654
655 policy->cpuinfo.transition_latency = 0;
656 for (i=0; i<perf->state_count; i++) {
657 if ((perf->states[i].transition_latency * 1000) >
658 policy->cpuinfo.transition_latency)
659 policy->cpuinfo.transition_latency =
660 perf->states[i].transition_latency * 1000;
661 }
662
663 data->max_freq = perf->states[0].core_frequency * 1000;
664
665 for (i=0; i<perf->state_count; i++) {
666 if (i>0 && perf->states[i].core_frequency >=
667 data->freq_table[valid_states-1].frequency / 1000)
668 continue;
669
670 data->freq_table[valid_states].index = i;
671 data->freq_table[valid_states].frequency =
672 perf->states[i].core_frequency * 1000;
673 valid_states++;
674 }
675 data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
676 perf->state = 0;
677
678 result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
679 if (result)
680 goto err_freqfree;
681
682 switch (perf->control_register.space_id) {
683 case ACPI_ADR_SPACE_SYSTEM_IO:
684
685 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
686 break;
687 case ACPI_ADR_SPACE_FIXED_HARDWARE:
688 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
689 policy->cur = get_cur_freq_on_cpu(cpu);
690 break;
691 default:
692 break;
693 }
694
695
696 acpi_processor_notify_smm(THIS_MODULE);
697
698
699 if (c->x86_vendor == X86_VENDOR_INTEL && c->cpuid_level >= 6) {
700 unsigned int ecx;
701 ecx = cpuid_ecx(6);
702 if (ecx & CPUID_6_ECX_APERFMPERF_CAPABILITY)
703 acpi_cpufreq_driver.getavg = get_measured_perf;
704 }
705
706 dprintk("CPU%u - ACPI performance management activated.\n", cpu);
707 for (i = 0; i < perf->state_count; i++)
708 dprintk(" %cP%d: %d MHz, %d mW, %d uS\n",
709 (i == perf->state ? '*' : ' '), i,
710 (u32) perf->states[i].core_frequency,
711 (u32) perf->states[i].power,
712 (u32) perf->states[i].transition_latency);
713
714 cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
715
716
717
718
719
720 data->resume = 1;
721
722 return result;
723
724err_freqfree:
725 kfree(data->freq_table);
726err_unreg:
727 acpi_processor_unregister_performance(perf, cpu);
728err_free:
729 kfree(data);
730 per_cpu(drv_data, cpu) = NULL;
731
732 return result;
733}
734
735static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
736{
737 struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
738
739 dprintk("acpi_cpufreq_cpu_exit\n");
740
741 if (data) {
742 cpufreq_frequency_table_put_attr(policy->cpu);
743 per_cpu(drv_data, policy->cpu) = NULL;
744 acpi_processor_unregister_performance(data->acpi_data,
745 policy->cpu);
746 kfree(data);
747 }
748
749 return 0;
750}
751
752static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
753{
754 struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
755
756 dprintk("acpi_cpufreq_resume\n");
757
758 data->resume = 1;
759
760 return 0;
761}
762
763static struct freq_attr *acpi_cpufreq_attr[] = {
764 &cpufreq_freq_attr_scaling_available_freqs,
765 NULL,
766};
767
768static struct cpufreq_driver acpi_cpufreq_driver = {
769 .verify = acpi_cpufreq_verify,
770 .target = acpi_cpufreq_target,
771 .init = acpi_cpufreq_cpu_init,
772 .exit = acpi_cpufreq_cpu_exit,
773 .resume = acpi_cpufreq_resume,
774 .name = "acpi-cpufreq",
775 .owner = THIS_MODULE,
776 .attr = acpi_cpufreq_attr,
777};
778
779static int __init acpi_cpufreq_init(void)
780{
781 int ret;
782
783 if (acpi_disabled)
784 return 0;
785
786 dprintk("acpi_cpufreq_init\n");
787
788 ret = acpi_cpufreq_early_init();
789 if (ret)
790 return ret;
791
792 ret = cpufreq_register_driver(&acpi_cpufreq_driver);
793 if (ret)
794 free_percpu(acpi_perf_data);
795
796 return ret;
797}
798
799static void __exit acpi_cpufreq_exit(void)
800{
801 dprintk("acpi_cpufreq_exit\n");
802
803 cpufreq_unregister_driver(&acpi_cpufreq_driver);
804
805 free_percpu(acpi_perf_data);
806}
807
808module_param(acpi_pstate_strict, uint, 0644);
809MODULE_PARM_DESC(acpi_pstate_strict,
810 "value 0 or non-zero. non-zero -> strict ACPI checks are "
811 "performed during frequency changes.");
812
813late_initcall(acpi_cpufreq_init);
814module_exit(acpi_cpufreq_exit);
815
816MODULE_ALIAS("acpi");