1 /*
2 * acpi-cpufreq.c - ACPI Processor P-States Driver ($Revision: 1.4 $)
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) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
8 *
9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
10 *
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.
15 *
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.
20 *
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.
24 *
25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
26 */
27
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
49 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
50 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
51 MODULE_LICENSE("GPL");
52
53 enum {
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
62 struct 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
70 static DEFINE_PER_CPU(struct acpi_cpufreq_data *, drv_data);
71
72 /* acpi_perf_data is a pointer to percpu data. */
73 static struct acpi_processor_performance *acpi_perf_data;
74
75 static struct cpufreq_driver acpi_cpufreq_driver;
76
77 static unsigned int acpi_pstate_strict;
78
79 static 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
90 static 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
104 static 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
119 static 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
131 struct msr_addr {
132 u32 reg;
133 };
134
135 struct io_addr {
136 u16 port;
137 u8 bit_width;
138 };
139
140 typedef union {
141 struct msr_addr msr;
142 struct io_addr io;
143 } drv_addr_union;
144
145 struct drv_cmd {
146 unsigned int type;
147 cpumask_t mask;
148 drv_addr_union addr;
149 u32 val;
150 };
151
152 static 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
170 static 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
190 static 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(current, cmd->mask);
196 do_drv_read(cmd);
197 set_cpus_allowed(current, saved_mask);
198 }
199
200 static 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(i, cmd->mask) {
206 set_cpus_allowed(current, cpumask_of_cpu(i));
207 do_drv_write(cmd);
208 }
209
210 set_cpus_allowed(current, saved_mask);
211 return;
212 }
213
214 static u32 get_cur_val(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 * Return the measured active (C0) frequency on this CPU since last call
248 * to this function.
249 * Input: cpu number
250 * Return: Average CPU frequency in terms of max frequency (zero on error)
251 *
252 * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
253 * over a period of time, while CPU is in C0 state.
254 * IA32_MPERF counts at the rate of max advertised frequency
255 * IA32_APERF counts at the rate of actual CPU frequency
256 * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
257 * no meaning should be associated with absolute values of these MSRs.
258 */
259 static unsigned int get_measured_perf(unsigned int cpu)
260 {
261 union {
262 struct {
263 u32 lo;
264 u32 hi;
265 } split;
266 u64 whole;
267 } aperf_cur, mperf_cur;
268
269 cpumask_t saved_mask;
270 unsigned int perf_percent;
271 unsigned int retval;
272
273 saved_mask = current->cpus_allowed;
274 set_cpus_allowed(current, cpumask_of_cpu(cpu));
275 if (get_cpu() != cpu) {
276 /* We were not able to run on requested processor */
277 put_cpu();
278 return 0;
279 }
280
281 rdmsr(MSR_IA32_APERF, aperf_cur.split.lo, aperf_cur.split.hi);
282 rdmsr(MSR_IA32_MPERF, mperf_cur.split.lo, mperf_cur.split.hi);
283
284 wrmsr(MSR_IA32_APERF, 0,0);
285 wrmsr(MSR_IA32_MPERF, 0,0);
286
287 #ifdef __i386__
288 /*
289 * We dont want to do 64 bit divide with 32 bit kernel
290 * Get an approximate value. Return failure in case we cannot get
291 * an approximate value.
292 */
293 if (unlikely(aperf_cur.split.hi || mperf_cur.split.hi)) {
294 int shift_count;
295 u32 h;
296
297 h = max_t(u32, aperf_cur.split.hi, mperf_cur.split.hi);
298 shift_count = fls(h);
299
300 aperf_cur.whole >>= shift_count;
301 mperf_cur.whole >>= shift_count;
302 }
303
304 if (((unsigned long)(-1) / 100) < aperf_cur.split.lo) {
305 int shift_count = 7;
306 aperf_cur.split.lo >>= shift_count;
307 mperf_cur.split.lo >>= shift_count;
308 }
309
310 if (aperf_cur.split.lo && mperf_cur.split.lo)
311 perf_percent = (aperf_cur.split.lo * 100) / mperf_cur.split.lo;
312 else
313 perf_percent = 0;
314
315 #else
316 if (unlikely(((unsigned long)(-1) / 100) < aperf_cur.whole)) {
317 int shift_count = 7;
318 aperf_cur.whole >>= shift_count;
319 mperf_cur.whole >>= shift_count;
320 }
321
322 if (aperf_cur.whole && mperf_cur.whole)
323 perf_percent = (aperf_cur.whole * 100) / mperf_cur.whole;
324 else
325 perf_percent = 0;
326
327 #endif
328
329 retval = per_cpu(drv_data, cpu)->max_freq * perf_percent / 100;
330
331 put_cpu();
332 set_cpus_allowed(current, saved_mask);
333
334 dprintk("cpu %d: performance percent %d\n", cpu, perf_percent);
335 return retval;
336 }
337
338 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
339 {
340 struct acpi_cpufreq_data *data = per_cpu(drv_data, cpu);
341 unsigned int freq;
342
343 dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
344
345 if (unlikely(data == NULL ||
346 data->acpi_data == NULL || data->freq_table == NULL)) {
347 return 0;
348 }
349
350 freq = extract_freq(get_cur_val(cpumask_of_cpu(cpu)), data);
351 dprintk("cur freq = %u\n", freq);
352
353 return freq;
354 }
355
356 static unsigned int check_freqs(cpumask_t mask, unsigned int freq,
357 struct acpi_cpufreq_data *data)
358 {
359 unsigned int cur_freq;
360 unsigned int i;
361
362 for (i=0; i<100; i++) {
363 cur_freq = extract_freq(get_cur_val(mask), data);
364 if (cur_freq == freq)
365 return 1;
366 udelay(10);
367 }
368 return 0;
369 }
370
371 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
372 unsigned int target_freq, unsigned int relation)
373 {
374 struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
375 struct acpi_processor_performance *perf;
376 struct cpufreq_freqs freqs;
377 cpumask_t online_policy_cpus;
378 struct drv_cmd cmd;
379 unsigned int next_state = 0; /* Index into freq_table */
380 unsigned int next_perf_state = 0; /* Index into perf table */
381 unsigned int i;
382 int result = 0;
383
384 dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
385
386 if (unlikely(data == NULL ||
387 data->acpi_data == NULL || data->freq_table == NULL)) {
388 return -ENODEV;
389 }
390
391 perf = data->acpi_data;
392 result = cpufreq_frequency_table_target(policy,
393 data->freq_table,
394 target_freq,
395 relation, &next_state);
396 if (unlikely(result))
397 return -ENODEV;
398
399 #ifdef CONFIG_HOTPLUG_CPU
400 /* cpufreq holds the hotplug lock, so we are safe from here on */
401 cpus_and(online_policy_cpus, cpu_online_map, policy->cpus);
402 #else
403 online_policy_cpus = policy->cpus;
404 #endif
405
406 next_perf_state = data->freq_table[next_state].index;
407 if (perf->state == next_perf_state) {
408 if (unlikely(data->resume)) {
409 dprintk("Called after resume, resetting to P%d\n",
410 next_perf_state);
411 data->resume = 0;
412 } else {
413 dprintk("Already at target state (P%d)\n",
414 next_perf_state);
415 return 0;
416 }
417 }
418
419 switch (data->cpu_feature) {
420 case SYSTEM_INTEL_MSR_CAPABLE:
421 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
422 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
423 cmd.val = (u32) perf->states[next_perf_state].control;
424 break;
425 case SYSTEM_IO_CAPABLE:
426 cmd.type = SYSTEM_IO_CAPABLE;
427 cmd.addr.io.port = perf->control_register.address;
428 cmd.addr.io.bit_width = perf->control_register.bit_width;
429 cmd.val = (u32) perf->states[next_perf_state].control;
430 break;
431 default:
432 return -ENODEV;
433 }
434
435 cpus_clear(cmd.mask);
436
437 if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
438 cmd.mask = online_policy_cpus;
439 else
440 cpu_set(policy->cpu, cmd.mask);
441
442 freqs.old = perf->states[perf->state].core_frequency * 1000;
443 freqs.new = data->freq_table[next_state].frequency;
444 for_each_cpu_mask(i, cmd.mask) {
445 freqs.cpu = i;
446 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
447 }
448
449 drv_write(&cmd);
450
451 if (acpi_pstate_strict) {
452 if (!check_freqs(cmd.mask, freqs.new, data)) {
453 dprintk("acpi_cpufreq_target failed (%d)\n",
454 policy->cpu);
455 return -EAGAIN;
456 }
457 }
458
459 for_each_cpu_mask(i, cmd.mask) {
460 freqs.cpu = i;
461 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
462 }
463 perf->state = next_perf_state;
464
465 return result;
466 }
467
468 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
469 {
470 struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
471
472 dprintk("acpi_cpufreq_verify\n");
473
474 return cpufreq_frequency_table_verify(policy, data->freq_table);
475 }
476
477 static unsigned long
478 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
479 {
480 struct acpi_processor_performance *perf = data->acpi_data;
481
482 if (cpu_khz) {
483 /* search the closest match to cpu_khz */
484 unsigned int i;
485 unsigned long freq;
486 unsigned long freqn = perf->states[0].core_frequency * 1000;
487
488 for (i=0; i<(perf->state_count-1); i++) {
489 freq = freqn;
490 freqn = perf->states[i+1].core_frequency * 1000;
491 if ((2 * cpu_khz) > (freqn + freq)) {
492 perf->state = i;
493 return freq;
494 }
495 }
496 perf->state = perf->state_count-1;
497 return freqn;
498 } else {
499 /* assume CPU is at P0... */
500 perf->state = 0;
501 return perf->states[0].core_frequency * 1000;
502 }
503 }
504
505 /*
506 * acpi_cpufreq_early_init - initialize ACPI P-States library
507 *
508 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
509 * in order to determine correct frequency and voltage pairings. We can
510 * do _PDC and _PSD and find out the processor dependency for the
511 * actual init that will happen later...
512 */
513 static int __init acpi_cpufreq_early_init(void)
514 {
515 dprintk("acpi_cpufreq_early_init\n");
516
517 acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
518 if (!acpi_perf_data) {
519 dprintk("Memory allocation error for acpi_perf_data.\n");
520 return -ENOMEM;
521 }
522
523 /* Do initialization in ACPI core */
524 acpi_processor_preregister_performance(acpi_perf_data);
525 return 0;
526 }
527
528 #ifdef CONFIG_SMP
529 /*
530 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
531 * or do it in BIOS firmware and won't inform about it to OS. If not
532 * detected, this has a side effect of making CPU run at a different speed
533 * than OS intended it to run at. Detect it and handle it cleanly.
534 */
535 static int bios_with_sw_any_bug;
536
537 static int sw_any_bug_found(const struct dmi_system_id *d)
538 {
539 bios_with_sw_any_bug = 1;
540 return 0;
541 }
542
543 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
544 {
545 .callback = sw_any_bug_found,
546 .ident = "Supermicro Server X6DLP",
547 .matches = {
548 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
549 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
550 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
551 },
552 },
553 { }
554 };
555 #endif
556
557 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
558 {
559 unsigned int i;
560 unsigned int valid_states = 0;
561 unsigned int cpu = policy->cpu;
562 struct acpi_cpufreq_data *data;
563 unsigned int result = 0;
564 struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
565 struct acpi_processor_performance *perf;
566
567 dprintk("acpi_cpufreq_cpu_init\n");
568
569 data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
570 if (!data)
571 return -ENOMEM;
572
573 data->acpi_data = percpu_ptr(acpi_perf_data, cpu);
574 per_cpu(drv_data, cpu) = data;
575
576 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
577 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
578
579 result = acpi_processor_register_performance(data->acpi_data, cpu);
580 if (result)
581 goto err_free;
582
583 perf = data->acpi_data;
584 policy->shared_type = perf->shared_type;
585
586 /*
587 * Will let policy->cpus know about dependency only when software
588 * coordination is required.
589 */
590 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
591 policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
592 policy->cpus = perf->shared_cpu_map;
593 }
594
595 #ifdef CONFIG_SMP
596 dmi_check_system(sw_any_bug_dmi_table);
597 if (bios_with_sw_any_bug && cpus_weight(policy->cpus) == 1) {
598 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
599 policy->cpus = per_cpu(cpu_core_map, cpu);
600 }
601 #endif
602
603 /* capability check */
604 if (perf->state_count <= 1) {
605 dprintk("No P-States\n");
606 result = -ENODEV;
607 goto err_unreg;
608 }
609
610 if (perf->control_register.space_id != perf->status_register.space_id) {
611 result = -ENODEV;
612 goto err_unreg;
613 }
614
615 switch (perf->control_register.space_id) {
616 case ACPI_ADR_SPACE_SYSTEM_IO:
617 dprintk("SYSTEM IO addr space\n");
618 data->cpu_feature = SYSTEM_IO_CAPABLE;
619 break;
620 case ACPI_ADR_SPACE_FIXED_HARDWARE:
621 dprintk("HARDWARE addr space\n");
622 if (!check_est_cpu(cpu)) {
623 result = -ENODEV;
624 goto err_unreg;
625 }
626 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
627 break;
628 default:
629 dprintk("Unknown addr space %d\n",
630 (u32) (perf->control_register.space_id));
631 result = -ENODEV;
632 goto err_unreg;
633 }
634
635 data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
636 (perf->state_count+1), GFP_KERNEL);
637 if (!data->freq_table) {
638 result = -ENOMEM;
639 goto err_unreg;
640 }
641
642 /* detect transition latency */
643 policy->cpuinfo.transition_latency = 0;
644 for (i=0; i<perf->state_count; i++) {
645 if ((perf->states[i].transition_latency * 1000) >
646 policy->cpuinfo.transition_latency)
647 policy->cpuinfo.transition_latency =
648 perf->states[i].transition_latency * 1000;
649 }
650
651 data->max_freq = perf->states[0].core_frequency * 1000;
652 /* table init */
653 for (i=0; i<perf->state_count; i++) {
654 if (i>0 && perf->states[i].core_frequency >=
655 data->freq_table[valid_states-1].frequency / 1000)
656 continue;
657
658 data->freq_table[valid_states].index = i;
659 data->freq_table[valid_states].frequency =
660 perf->states[i].core_frequency * 1000;
661 valid_states++;
662 }
663 data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
664 perf->state = 0;
665
666 result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
667 if (result)
668 goto err_freqfree;
669
670 switch (perf->control_register.space_id) {
671 case ACPI_ADR_SPACE_SYSTEM_IO:
672 /* Current speed is unknown and not detectable by IO port */
673 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
674 break;
675 case ACPI_ADR_SPACE_FIXED_HARDWARE:
676 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
677 policy->cur = get_cur_freq_on_cpu(cpu);
678 break;
679 default:
680 break;
681 }
682
683 /* notify BIOS that we exist */
684 acpi_processor_notify_smm(THIS_MODULE);
685
686 /* Check for APERF/MPERF support in hardware */
687 if (c->x86_vendor == X86_VENDOR_INTEL && c->cpuid_level >= 6) {
688 unsigned int ecx;
689 ecx = cpuid_ecx(6);
690 if (ecx & CPUID_6_ECX_APERFMPERF_CAPABILITY)
691 acpi_cpufreq_driver.getavg = get_measured_perf;
692 }
693
694 dprintk("CPU%u - ACPI performance management activated.\n", cpu);
695 for (i = 0; i < perf->state_count; i++)
696 dprintk(" %cP%d: %d MHz, %d mW, %d uS\n",
697 (i == perf->state ? '*' : ' '), i,
698 (u32) perf->states[i].core_frequency,
699 (u32) perf->states[i].power,
700 (u32) perf->states[i].transition_latency);
701
702 cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
703
704 /*
705 * the first call to ->target() should result in us actually
706 * writing something to the appropriate registers.
707 */
708 data->resume = 1;
709
710 return result;
711
712 err_freqfree:
713 kfree(data->freq_table);
714 err_unreg:
715 acpi_processor_unregister_performance(perf, cpu);
716 err_free:
717 kfree(data);
718 per_cpu(drv_data, cpu) = NULL;
719
720 return result;
721 }
722
723 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
724 {
725 struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
726
727 dprintk("acpi_cpufreq_cpu_exit\n");
728
729 if (data) {
730 cpufreq_frequency_table_put_attr(policy->cpu);
731 per_cpu(drv_data, policy->cpu) = NULL;
732 acpi_processor_unregister_performance(data->acpi_data,
733 policy->cpu);
734 kfree(data);
735 }
736
737 return 0;
738 }
739
740 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
741 {
742 struct acpi_cpufreq_data *data = per_cpu(drv_data, policy->cpu);
743
744 dprintk("acpi_cpufreq_resume\n");
745
746 data->resume = 1;
747
748 return 0;
749 }
750
751 static struct freq_attr *acpi_cpufreq_attr[] = {
752 &cpufreq_freq_attr_scaling_available_freqs,
753 NULL,
754 };
755
756 static struct cpufreq_driver acpi_cpufreq_driver = {
757 .verify = acpi_cpufreq_verify,
758 .target = acpi_cpufreq_target,
759 .init = acpi_cpufreq_cpu_init,
760 .exit = acpi_cpufreq_cpu_exit,
761 .resume = acpi_cpufreq_resume,
762 .name = "acpi-cpufreq",
763 .owner = THIS_MODULE,
764 .attr = acpi_cpufreq_attr,
765 };
766
767 static int __init acpi_cpufreq_init(void)
768 {
769 int ret;
770
771 dprintk("acpi_cpufreq_init\n");
772
773 ret = acpi_cpufreq_early_init();
774 if (ret)
775 return ret;
776
777 return cpufreq_register_driver(&acpi_cpufreq_driver);
778 }
779
780 static void __exit acpi_cpufreq_exit(void)
781 {
782 dprintk("acpi_cpufreq_exit\n");
783
784 cpufreq_unregister_driver(&acpi_cpufreq_driver);
785
786 free_percpu(acpi_perf_data);
787
788 return;
789 }
790
791 module_param(acpi_pstate_strict, uint, 0644);
792 MODULE_PARM_DESC(acpi_pstate_strict,
793 "value 0 or non-zero. non-zero -> strict ACPI checks are "
794 "performed during frequency changes.");
795
796 late_initcall(acpi_cpufreq_init);
797 module_exit(acpi_cpufreq_exit);
798
799 MODULE_ALIAS("acpi");
800
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