oom: fix integer overflow of points in oom_badness
[linux-2.6.git] / drivers / cpufreq / acpi-cpufreq.c
1 /*
2  * acpi-cpufreq.c - ACPI Processor P-States Driver
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 #include <linux/slab.h>
37
38 #include <linux/acpi.h>
39 #include <linux/io.h>
40 #include <linux/delay.h>
41 #include <linux/uaccess.h>
42
43 #include <acpi/processor.h>
44
45 #include <asm/msr.h>
46 #include <asm/processor.h>
47 #include <asm/cpufeature.h>
48 #include "mperf.h"
49
50 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
51 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
52 MODULE_LICENSE("GPL");
53
54 enum {
55         UNDEFINED_CAPABLE = 0,
56         SYSTEM_INTEL_MSR_CAPABLE,
57         SYSTEM_IO_CAPABLE,
58 };
59
60 #define INTEL_MSR_RANGE         (0xffff)
61
62 struct acpi_cpufreq_data {
63         struct acpi_processor_performance *acpi_data;
64         struct cpufreq_frequency_table *freq_table;
65         unsigned int resume;
66         unsigned int cpu_feature;
67 };
68
69 static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
70
71 /* acpi_perf_data is a pointer to percpu data. */
72 static struct acpi_processor_performance __percpu *acpi_perf_data;
73
74 static struct cpufreq_driver acpi_cpufreq_driver;
75
76 static unsigned int acpi_pstate_strict;
77
78 static int check_est_cpu(unsigned int cpuid)
79 {
80         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
81
82         return cpu_has(cpu, X86_FEATURE_EST);
83 }
84
85 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
86 {
87         struct acpi_processor_performance *perf;
88         int i;
89
90         perf = data->acpi_data;
91
92         for (i = 0; i < perf->state_count; i++) {
93                 if (value == perf->states[i].status)
94                         return data->freq_table[i].frequency;
95         }
96         return 0;
97 }
98
99 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
100 {
101         int i;
102         struct acpi_processor_performance *perf;
103
104         msr &= INTEL_MSR_RANGE;
105         perf = data->acpi_data;
106
107         for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
108                 if (msr == perf->states[data->freq_table[i].index].status)
109                         return data->freq_table[i].frequency;
110         }
111         return data->freq_table[0].frequency;
112 }
113
114 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
115 {
116         switch (data->cpu_feature) {
117         case SYSTEM_INTEL_MSR_CAPABLE:
118                 return extract_msr(val, data);
119         case SYSTEM_IO_CAPABLE:
120                 return extract_io(val, data);
121         default:
122                 return 0;
123         }
124 }
125
126 struct msr_addr {
127         u32 reg;
128 };
129
130 struct io_addr {
131         u16 port;
132         u8 bit_width;
133 };
134
135 struct drv_cmd {
136         unsigned int type;
137         const struct cpumask *mask;
138         union {
139                 struct msr_addr msr;
140                 struct io_addr io;
141         } addr;
142         u32 val;
143 };
144
145 /* Called via smp_call_function_single(), on the target CPU */
146 static void do_drv_read(void *_cmd)
147 {
148         struct drv_cmd *cmd = _cmd;
149         u32 h;
150
151         switch (cmd->type) {
152         case SYSTEM_INTEL_MSR_CAPABLE:
153                 rdmsr(cmd->addr.msr.reg, cmd->val, h);
154                 break;
155         case SYSTEM_IO_CAPABLE:
156                 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
157                                 &cmd->val,
158                                 (u32)cmd->addr.io.bit_width);
159                 break;
160         default:
161                 break;
162         }
163 }
164
165 /* Called via smp_call_function_many(), on the target CPUs */
166 static void do_drv_write(void *_cmd)
167 {
168         struct drv_cmd *cmd = _cmd;
169         u32 lo, hi;
170
171         switch (cmd->type) {
172         case SYSTEM_INTEL_MSR_CAPABLE:
173                 rdmsr(cmd->addr.msr.reg, lo, hi);
174                 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
175                 wrmsr(cmd->addr.msr.reg, lo, hi);
176                 break;
177         case SYSTEM_IO_CAPABLE:
178                 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
179                                 cmd->val,
180                                 (u32)cmd->addr.io.bit_width);
181                 break;
182         default:
183                 break;
184         }
185 }
186
187 static void drv_read(struct drv_cmd *cmd)
188 {
189         int err;
190         cmd->val = 0;
191
192         err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
193         WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
194 }
195
196 static void drv_write(struct drv_cmd *cmd)
197 {
198         int this_cpu;
199
200         this_cpu = get_cpu();
201         if (cpumask_test_cpu(this_cpu, cmd->mask))
202                 do_drv_write(cmd);
203         smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
204         put_cpu();
205 }
206
207 static u32 get_cur_val(const struct cpumask *mask)
208 {
209         struct acpi_processor_performance *perf;
210         struct drv_cmd cmd;
211
212         if (unlikely(cpumask_empty(mask)))
213                 return 0;
214
215         switch (per_cpu(acfreq_data, cpumask_first(mask))->cpu_feature) {
216         case SYSTEM_INTEL_MSR_CAPABLE:
217                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
218                 cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
219                 break;
220         case SYSTEM_IO_CAPABLE:
221                 cmd.type = SYSTEM_IO_CAPABLE;
222                 perf = per_cpu(acfreq_data, cpumask_first(mask))->acpi_data;
223                 cmd.addr.io.port = perf->control_register.address;
224                 cmd.addr.io.bit_width = perf->control_register.bit_width;
225                 break;
226         default:
227                 return 0;
228         }
229
230         cmd.mask = mask;
231         drv_read(&cmd);
232
233         pr_debug("get_cur_val = %u\n", cmd.val);
234
235         return cmd.val;
236 }
237
238 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
239 {
240         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu);
241         unsigned int freq;
242         unsigned int cached_freq;
243
244         pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
245
246         if (unlikely(data == NULL ||
247                      data->acpi_data == NULL || data->freq_table == NULL)) {
248                 return 0;
249         }
250
251         cached_freq = data->freq_table[data->acpi_data->state].frequency;
252         freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
253         if (freq != cached_freq) {
254                 /*
255                  * The dreaded BIOS frequency change behind our back.
256                  * Force set the frequency on next target call.
257                  */
258                 data->resume = 1;
259         }
260
261         pr_debug("cur freq = %u\n", freq);
262
263         return freq;
264 }
265
266 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
267                                 struct acpi_cpufreq_data *data)
268 {
269         unsigned int cur_freq;
270         unsigned int i;
271
272         for (i = 0; i < 100; i++) {
273                 cur_freq = extract_freq(get_cur_val(mask), data);
274                 if (cur_freq == freq)
275                         return 1;
276                 udelay(10);
277         }
278         return 0;
279 }
280
281 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
282                                unsigned int target_freq, unsigned int relation)
283 {
284         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
285         struct acpi_processor_performance *perf;
286         struct cpufreq_freqs freqs;
287         struct drv_cmd cmd;
288         unsigned int next_state = 0; /* Index into freq_table */
289         unsigned int next_perf_state = 0; /* Index into perf table */
290         unsigned int i;
291         int result = 0;
292
293         pr_debug("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
294
295         if (unlikely(data == NULL ||
296              data->acpi_data == NULL || data->freq_table == NULL)) {
297                 return -ENODEV;
298         }
299
300         perf = data->acpi_data;
301         result = cpufreq_frequency_table_target(policy,
302                                                 data->freq_table,
303                                                 target_freq,
304                                                 relation, &next_state);
305         if (unlikely(result)) {
306                 result = -ENODEV;
307                 goto out;
308         }
309
310         next_perf_state = data->freq_table[next_state].index;
311         if (perf->state == next_perf_state) {
312                 if (unlikely(data->resume)) {
313                         pr_debug("Called after resume, resetting to P%d\n",
314                                 next_perf_state);
315                         data->resume = 0;
316                 } else {
317                         pr_debug("Already at target state (P%d)\n",
318                                 next_perf_state);
319                         goto out;
320                 }
321         }
322
323         switch (data->cpu_feature) {
324         case SYSTEM_INTEL_MSR_CAPABLE:
325                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
326                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
327                 cmd.val = (u32) perf->states[next_perf_state].control;
328                 break;
329         case SYSTEM_IO_CAPABLE:
330                 cmd.type = SYSTEM_IO_CAPABLE;
331                 cmd.addr.io.port = perf->control_register.address;
332                 cmd.addr.io.bit_width = perf->control_register.bit_width;
333                 cmd.val = (u32) perf->states[next_perf_state].control;
334                 break;
335         default:
336                 result = -ENODEV;
337                 goto out;
338         }
339
340         /* cpufreq holds the hotplug lock, so we are safe from here on */
341         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
342                 cmd.mask = policy->cpus;
343         else
344                 cmd.mask = cpumask_of(policy->cpu);
345
346         freqs.old = perf->states[perf->state].core_frequency * 1000;
347         freqs.new = data->freq_table[next_state].frequency;
348         for_each_cpu(i, policy->cpus) {
349                 freqs.cpu = i;
350                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
351         }
352
353         drv_write(&cmd);
354
355         if (acpi_pstate_strict) {
356                 if (!check_freqs(cmd.mask, freqs.new, data)) {
357                         pr_debug("acpi_cpufreq_target failed (%d)\n",
358                                 policy->cpu);
359                         result = -EAGAIN;
360                         goto out;
361                 }
362         }
363
364         for_each_cpu(i, policy->cpus) {
365                 freqs.cpu = i;
366                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
367         }
368         perf->state = next_perf_state;
369
370 out:
371         return result;
372 }
373
374 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
375 {
376         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
377
378         pr_debug("acpi_cpufreq_verify\n");
379
380         return cpufreq_frequency_table_verify(policy, data->freq_table);
381 }
382
383 static unsigned long
384 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
385 {
386         struct acpi_processor_performance *perf = data->acpi_data;
387
388         if (cpu_khz) {
389                 /* search the closest match to cpu_khz */
390                 unsigned int i;
391                 unsigned long freq;
392                 unsigned long freqn = perf->states[0].core_frequency * 1000;
393
394                 for (i = 0; i < (perf->state_count-1); i++) {
395                         freq = freqn;
396                         freqn = perf->states[i+1].core_frequency * 1000;
397                         if ((2 * cpu_khz) > (freqn + freq)) {
398                                 perf->state = i;
399                                 return freq;
400                         }
401                 }
402                 perf->state = perf->state_count-1;
403                 return freqn;
404         } else {
405                 /* assume CPU is at P0... */
406                 perf->state = 0;
407                 return perf->states[0].core_frequency * 1000;
408         }
409 }
410
411 static void free_acpi_perf_data(void)
412 {
413         unsigned int i;
414
415         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
416         for_each_possible_cpu(i)
417                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
418                                  ->shared_cpu_map);
419         free_percpu(acpi_perf_data);
420 }
421
422 /*
423  * acpi_cpufreq_early_init - initialize ACPI P-States library
424  *
425  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
426  * in order to determine correct frequency and voltage pairings. We can
427  * do _PDC and _PSD and find out the processor dependency for the
428  * actual init that will happen later...
429  */
430 static int __init acpi_cpufreq_early_init(void)
431 {
432         unsigned int i;
433         pr_debug("acpi_cpufreq_early_init\n");
434
435         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
436         if (!acpi_perf_data) {
437                 pr_debug("Memory allocation error for acpi_perf_data.\n");
438                 return -ENOMEM;
439         }
440         for_each_possible_cpu(i) {
441                 if (!zalloc_cpumask_var_node(
442                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
443                         GFP_KERNEL, cpu_to_node(i))) {
444
445                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
446                         free_acpi_perf_data();
447                         return -ENOMEM;
448                 }
449         }
450
451         /* Do initialization in ACPI core */
452         acpi_processor_preregister_performance(acpi_perf_data);
453         return 0;
454 }
455
456 #ifdef CONFIG_SMP
457 /*
458  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
459  * or do it in BIOS firmware and won't inform about it to OS. If not
460  * detected, this has a side effect of making CPU run at a different speed
461  * than OS intended it to run at. Detect it and handle it cleanly.
462  */
463 static int bios_with_sw_any_bug;
464
465 static int sw_any_bug_found(const struct dmi_system_id *d)
466 {
467         bios_with_sw_any_bug = 1;
468         return 0;
469 }
470
471 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
472         {
473                 .callback = sw_any_bug_found,
474                 .ident = "Supermicro Server X6DLP",
475                 .matches = {
476                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
477                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
478                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
479                 },
480         },
481         { }
482 };
483
484 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
485 {
486         /* Intel Xeon Processor 7100 Series Specification Update
487          * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
488          * AL30: A Machine Check Exception (MCE) Occurring during an
489          * Enhanced Intel SpeedStep Technology Ratio Change May Cause
490          * Both Processor Cores to Lock Up. */
491         if (c->x86_vendor == X86_VENDOR_INTEL) {
492                 if ((c->x86 == 15) &&
493                     (c->x86_model == 6) &&
494                     (c->x86_mask == 8)) {
495                         printk(KERN_INFO "acpi-cpufreq: Intel(R) "
496                             "Xeon(R) 7100 Errata AL30, processors may "
497                             "lock up on frequency changes: disabling "
498                             "acpi-cpufreq.\n");
499                         return -ENODEV;
500                     }
501                 }
502         return 0;
503 }
504 #endif
505
506 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
507 {
508         unsigned int i;
509         unsigned int valid_states = 0;
510         unsigned int cpu = policy->cpu;
511         struct acpi_cpufreq_data *data;
512         unsigned int result = 0;
513         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
514         struct acpi_processor_performance *perf;
515 #ifdef CONFIG_SMP
516         static int blacklisted;
517 #endif
518
519         pr_debug("acpi_cpufreq_cpu_init\n");
520
521 #ifdef CONFIG_SMP
522         if (blacklisted)
523                 return blacklisted;
524         blacklisted = acpi_cpufreq_blacklist(c);
525         if (blacklisted)
526                 return blacklisted;
527 #endif
528
529         data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
530         if (!data)
531                 return -ENOMEM;
532
533         data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
534         per_cpu(acfreq_data, cpu) = data;
535
536         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
537                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
538
539         result = acpi_processor_register_performance(data->acpi_data, cpu);
540         if (result)
541                 goto err_free;
542
543         perf = data->acpi_data;
544         policy->shared_type = perf->shared_type;
545
546         /*
547          * Will let policy->cpus know about dependency only when software
548          * coordination is required.
549          */
550         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
551             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
552                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
553         }
554         cpumask_copy(policy->related_cpus, perf->shared_cpu_map);
555
556 #ifdef CONFIG_SMP
557         dmi_check_system(sw_any_bug_dmi_table);
558         if (bios_with_sw_any_bug && cpumask_weight(policy->cpus) == 1) {
559                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
560                 cpumask_copy(policy->cpus, cpu_core_mask(cpu));
561         }
562 #endif
563
564         /* capability check */
565         if (perf->state_count <= 1) {
566                 pr_debug("No P-States\n");
567                 result = -ENODEV;
568                 goto err_unreg;
569         }
570
571         if (perf->control_register.space_id != perf->status_register.space_id) {
572                 result = -ENODEV;
573                 goto err_unreg;
574         }
575
576         switch (perf->control_register.space_id) {
577         case ACPI_ADR_SPACE_SYSTEM_IO:
578                 pr_debug("SYSTEM IO addr space\n");
579                 data->cpu_feature = SYSTEM_IO_CAPABLE;
580                 break;
581         case ACPI_ADR_SPACE_FIXED_HARDWARE:
582                 pr_debug("HARDWARE addr space\n");
583                 if (!check_est_cpu(cpu)) {
584                         result = -ENODEV;
585                         goto err_unreg;
586                 }
587                 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
588                 break;
589         default:
590                 pr_debug("Unknown addr space %d\n",
591                         (u32) (perf->control_register.space_id));
592                 result = -ENODEV;
593                 goto err_unreg;
594         }
595
596         data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
597                     (perf->state_count+1), GFP_KERNEL);
598         if (!data->freq_table) {
599                 result = -ENOMEM;
600                 goto err_unreg;
601         }
602
603         /* detect transition latency */
604         policy->cpuinfo.transition_latency = 0;
605         for (i = 0; i < perf->state_count; i++) {
606                 if ((perf->states[i].transition_latency * 1000) >
607                     policy->cpuinfo.transition_latency)
608                         policy->cpuinfo.transition_latency =
609                             perf->states[i].transition_latency * 1000;
610         }
611
612         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
613         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
614             policy->cpuinfo.transition_latency > 20 * 1000) {
615                 policy->cpuinfo.transition_latency = 20 * 1000;
616                 printk_once(KERN_INFO
617                             "P-state transition latency capped at 20 uS\n");
618         }
619
620         /* table init */
621         for (i = 0; i < perf->state_count; i++) {
622                 if (i > 0 && perf->states[i].core_frequency >=
623                     data->freq_table[valid_states-1].frequency / 1000)
624                         continue;
625
626                 data->freq_table[valid_states].index = i;
627                 data->freq_table[valid_states].frequency =
628                     perf->states[i].core_frequency * 1000;
629                 valid_states++;
630         }
631         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
632         perf->state = 0;
633
634         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
635         if (result)
636                 goto err_freqfree;
637
638         if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
639                 printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
640
641         switch (perf->control_register.space_id) {
642         case ACPI_ADR_SPACE_SYSTEM_IO:
643                 /* Current speed is unknown and not detectable by IO port */
644                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
645                 break;
646         case ACPI_ADR_SPACE_FIXED_HARDWARE:
647                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
648                 policy->cur = get_cur_freq_on_cpu(cpu);
649                 break;
650         default:
651                 break;
652         }
653
654         /* notify BIOS that we exist */
655         acpi_processor_notify_smm(THIS_MODULE);
656
657         /* Check for APERF/MPERF support in hardware */
658         if (boot_cpu_has(X86_FEATURE_APERFMPERF))
659                 acpi_cpufreq_driver.getavg = cpufreq_get_measured_perf;
660
661         pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
662         for (i = 0; i < perf->state_count; i++)
663                 pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
664                         (i == perf->state ? '*' : ' '), i,
665                         (u32) perf->states[i].core_frequency,
666                         (u32) perf->states[i].power,
667                         (u32) perf->states[i].transition_latency);
668
669         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
670
671         /*
672          * the first call to ->target() should result in us actually
673          * writing something to the appropriate registers.
674          */
675         data->resume = 1;
676
677         return result;
678
679 err_freqfree:
680         kfree(data->freq_table);
681 err_unreg:
682         acpi_processor_unregister_performance(perf, cpu);
683 err_free:
684         kfree(data);
685         per_cpu(acfreq_data, cpu) = NULL;
686
687         return result;
688 }
689
690 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
691 {
692         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
693
694         pr_debug("acpi_cpufreq_cpu_exit\n");
695
696         if (data) {
697                 cpufreq_frequency_table_put_attr(policy->cpu);
698                 per_cpu(acfreq_data, policy->cpu) = NULL;
699                 acpi_processor_unregister_performance(data->acpi_data,
700                                                       policy->cpu);
701                 kfree(data->freq_table);
702                 kfree(data);
703         }
704
705         return 0;
706 }
707
708 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
709 {
710         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
711
712         pr_debug("acpi_cpufreq_resume\n");
713
714         data->resume = 1;
715
716         return 0;
717 }
718
719 static struct freq_attr *acpi_cpufreq_attr[] = {
720         &cpufreq_freq_attr_scaling_available_freqs,
721         NULL,
722 };
723
724 static struct cpufreq_driver acpi_cpufreq_driver = {
725         .verify         = acpi_cpufreq_verify,
726         .target         = acpi_cpufreq_target,
727         .bios_limit     = acpi_processor_get_bios_limit,
728         .init           = acpi_cpufreq_cpu_init,
729         .exit           = acpi_cpufreq_cpu_exit,
730         .resume         = acpi_cpufreq_resume,
731         .name           = "acpi-cpufreq",
732         .owner          = THIS_MODULE,
733         .attr           = acpi_cpufreq_attr,
734 };
735
736 static int __init acpi_cpufreq_init(void)
737 {
738         int ret;
739
740         if (acpi_disabled)
741                 return 0;
742
743         pr_debug("acpi_cpufreq_init\n");
744
745         ret = acpi_cpufreq_early_init();
746         if (ret)
747                 return ret;
748
749         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
750         if (ret)
751                 free_acpi_perf_data();
752
753         return ret;
754 }
755
756 static void __exit acpi_cpufreq_exit(void)
757 {
758         pr_debug("acpi_cpufreq_exit\n");
759
760         cpufreq_unregister_driver(&acpi_cpufreq_driver);
761
762         free_acpi_perf_data();
763 }
764
765 module_param(acpi_pstate_strict, uint, 0644);
766 MODULE_PARM_DESC(acpi_pstate_strict,
767         "value 0 or non-zero. non-zero -> strict ACPI checks are "
768         "performed during frequency changes.");
769
770 late_initcall(acpi_cpufreq_init);
771 module_exit(acpi_cpufreq_exit);
772
773 MODULE_ALIAS("acpi");