Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq
[linux-2.6.git] / arch / i386 / kernel / cpu / cpufreq / acpi-cpufreq.c
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 struct acpi_cpufreq_data *drv_data[NR_CPUS];
71 static struct acpi_processor_performance *acpi_perf_data[NR_CPUS];
72
73 static struct cpufreq_driver acpi_cpufreq_driver;
74
75 static unsigned int acpi_pstate_strict;
76
77 static int check_est_cpu(unsigned int cpuid)
78 {
79         struct cpuinfo_x86 *cpu = &cpu_data[cpuid];
80
81         if (cpu->x86_vendor != X86_VENDOR_INTEL ||
82             !cpu_has(cpu, X86_FEATURE_EST))
83                 return 0;
84
85         return 1;
86 }
87
88 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
89 {
90         struct acpi_processor_performance *perf;
91         int i;
92
93         perf = data->acpi_data;
94
95         for (i=0; i<perf->state_count; i++) {
96                 if (value == perf->states[i].status)
97                         return data->freq_table[i].frequency;
98         }
99         return 0;
100 }
101
102 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
103 {
104         int i;
105         struct acpi_processor_performance *perf;
106
107         msr &= INTEL_MSR_RANGE;
108         perf = data->acpi_data;
109
110         for (i=0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
111                 if (msr == perf->states[data->freq_table[i].index].status)
112                         return data->freq_table[i].frequency;
113         }
114         return data->freq_table[0].frequency;
115 }
116
117 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
118 {
119         switch (data->cpu_feature) {
120         case SYSTEM_INTEL_MSR_CAPABLE:
121                 return extract_msr(val, data);
122         case SYSTEM_IO_CAPABLE:
123                 return extract_io(val, data);
124         default:
125                 return 0;
126         }
127 }
128
129 struct msr_addr {
130         u32 reg;
131 };
132
133 struct io_addr {
134         u16 port;
135         u8 bit_width;
136 };
137
138 typedef union {
139         struct msr_addr msr;
140         struct io_addr io;
141 } drv_addr_union;
142
143 struct drv_cmd {
144         unsigned int type;
145         cpumask_t mask;
146         drv_addr_union addr;
147         u32 val;
148 };
149
150 static void do_drv_read(struct drv_cmd *cmd)
151 {
152         u32 h;
153
154         switch (cmd->type) {
155         case SYSTEM_INTEL_MSR_CAPABLE:
156                 rdmsr(cmd->addr.msr.reg, cmd->val, h);
157                 break;
158         case SYSTEM_IO_CAPABLE:
159                 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
160                                 &cmd->val,
161                                 (u32)cmd->addr.io.bit_width);
162                 break;
163         default:
164                 break;
165         }
166 }
167
168 static void do_drv_write(struct drv_cmd *cmd)
169 {
170         u32 lo, hi;
171
172         switch (cmd->type) {
173         case SYSTEM_INTEL_MSR_CAPABLE:
174                 rdmsr(cmd->addr.msr.reg, lo, hi);
175                 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
176                 wrmsr(cmd->addr.msr.reg, lo, hi);
177                 break;
178         case SYSTEM_IO_CAPABLE:
179                 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
180                                 cmd->val,
181                                 (u32)cmd->addr.io.bit_width);
182                 break;
183         default:
184                 break;
185         }
186 }
187
188 static void drv_read(struct drv_cmd *cmd)
189 {
190         cpumask_t saved_mask = current->cpus_allowed;
191         cmd->val = 0;
192
193         set_cpus_allowed(current, cmd->mask);
194         do_drv_read(cmd);
195         set_cpus_allowed(current, saved_mask);
196 }
197
198 static void drv_write(struct drv_cmd *cmd)
199 {
200         cpumask_t saved_mask = current->cpus_allowed;
201         unsigned int i;
202
203         for_each_cpu_mask(i, cmd->mask) {
204                 set_cpus_allowed(current, cpumask_of_cpu(i));
205                 do_drv_write(cmd);
206         }
207
208         set_cpus_allowed(current, saved_mask);
209         return;
210 }
211
212 static u32 get_cur_val(cpumask_t mask)
213 {
214         struct acpi_processor_performance *perf;
215         struct drv_cmd cmd;
216
217         if (unlikely(cpus_empty(mask)))
218                 return 0;
219
220         switch (drv_data[first_cpu(mask)]->cpu_feature) {
221         case SYSTEM_INTEL_MSR_CAPABLE:
222                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
223                 cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
224                 break;
225         case SYSTEM_IO_CAPABLE:
226                 cmd.type = SYSTEM_IO_CAPABLE;
227                 perf = drv_data[first_cpu(mask)]->acpi_data;
228                 cmd.addr.io.port = perf->control_register.address;
229                 cmd.addr.io.bit_width = perf->control_register.bit_width;
230                 break;
231         default:
232                 return 0;
233         }
234
235         cmd.mask = mask;
236
237         drv_read(&cmd);
238
239         dprintk("get_cur_val = %u\n", cmd.val);
240
241         return cmd.val;
242 }
243
244 /*
245  * Return the measured active (C0) frequency on this CPU since last call
246  * to this function.
247  * Input: cpu number
248  * Return: Average CPU frequency in terms of max frequency (zero on error)
249  *
250  * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
251  * over a period of time, while CPU is in C0 state.
252  * IA32_MPERF counts at the rate of max advertised frequency
253  * IA32_APERF counts at the rate of actual CPU frequency
254  * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
255  * no meaning should be associated with absolute values of these MSRs.
256  */
257 static unsigned int get_measured_perf(unsigned int cpu)
258 {
259         union {
260                 struct {
261                         u32 lo;
262                         u32 hi;
263                 } split;
264                 u64 whole;
265         } aperf_cur, mperf_cur;
266
267         cpumask_t saved_mask;
268         unsigned int perf_percent;
269         unsigned int retval;
270
271         saved_mask = current->cpus_allowed;
272         set_cpus_allowed(current, cpumask_of_cpu(cpu));
273         if (get_cpu() != cpu) {
274                 /* We were not able to run on requested processor */
275                 put_cpu();
276                 return 0;
277         }
278
279         rdmsr(MSR_IA32_APERF, aperf_cur.split.lo, aperf_cur.split.hi);
280         rdmsr(MSR_IA32_MPERF, mperf_cur.split.lo, mperf_cur.split.hi);
281
282         wrmsr(MSR_IA32_APERF, 0,0);
283         wrmsr(MSR_IA32_MPERF, 0,0);
284
285 #ifdef __i386__
286         /*
287          * We dont want to do 64 bit divide with 32 bit kernel
288          * Get an approximate value. Return failure in case we cannot get
289          * an approximate value.
290          */
291         if (unlikely(aperf_cur.split.hi || mperf_cur.split.hi)) {
292                 int shift_count;
293                 u32 h;
294
295                 h = max_t(u32, aperf_cur.split.hi, mperf_cur.split.hi);
296                 shift_count = fls(h);
297
298                 aperf_cur.whole >>= shift_count;
299                 mperf_cur.whole >>= shift_count;
300         }
301
302         if (((unsigned long)(-1) / 100) < aperf_cur.split.lo) {
303                 int shift_count = 7;
304                 aperf_cur.split.lo >>= shift_count;
305                 mperf_cur.split.lo >>= shift_count;
306         }
307
308         if (aperf_cur.split.lo && mperf_cur.split.lo)
309                 perf_percent = (aperf_cur.split.lo * 100) / mperf_cur.split.lo;
310         else
311                 perf_percent = 0;
312
313 #else
314         if (unlikely(((unsigned long)(-1) / 100) < aperf_cur.whole)) {
315                 int shift_count = 7;
316                 aperf_cur.whole >>= shift_count;
317                 mperf_cur.whole >>= shift_count;
318         }
319
320         if (aperf_cur.whole && mperf_cur.whole)
321                 perf_percent = (aperf_cur.whole * 100) / mperf_cur.whole;
322         else
323                 perf_percent = 0;
324
325 #endif
326
327         retval = drv_data[cpu]->max_freq * perf_percent / 100;
328
329         put_cpu();
330         set_cpus_allowed(current, saved_mask);
331
332         dprintk("cpu %d: performance percent %d\n", cpu, perf_percent);
333         return retval;
334 }
335
336 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
337 {
338         struct acpi_cpufreq_data *data = drv_data[cpu];
339         unsigned int freq;
340
341         dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
342
343         if (unlikely(data == NULL ||
344                      data->acpi_data == NULL || data->freq_table == NULL)) {
345                 return 0;
346         }
347
348         freq = extract_freq(get_cur_val(cpumask_of_cpu(cpu)), data);
349         dprintk("cur freq = %u\n", freq);
350
351         return freq;
352 }
353
354 static unsigned int check_freqs(cpumask_t mask, unsigned int freq,
355                                 struct acpi_cpufreq_data *data)
356 {
357         unsigned int cur_freq;
358         unsigned int i;
359
360         for (i=0; i<100; i++) {
361                 cur_freq = extract_freq(get_cur_val(mask), data);
362                 if (cur_freq == freq)
363                         return 1;
364                 udelay(10);
365         }
366         return 0;
367 }
368
369 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
370                                unsigned int target_freq, unsigned int relation)
371 {
372         struct acpi_cpufreq_data *data = drv_data[policy->cpu];
373         struct acpi_processor_performance *perf;
374         struct cpufreq_freqs freqs;
375         cpumask_t online_policy_cpus;
376         struct drv_cmd cmd;
377         unsigned int next_state = 0; /* Index into freq_table */
378         unsigned int next_perf_state = 0; /* Index into perf table */
379         unsigned int i;
380         int result = 0;
381
382         dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
383
384         if (unlikely(data == NULL ||
385              data->acpi_data == NULL || data->freq_table == NULL)) {
386                 return -ENODEV;
387         }
388
389         perf = data->acpi_data;
390         result = cpufreq_frequency_table_target(policy,
391                                                 data->freq_table,
392                                                 target_freq,
393                                                 relation, &next_state);
394         if (unlikely(result))
395                 return -ENODEV;
396
397 #ifdef CONFIG_HOTPLUG_CPU
398         /* cpufreq holds the hotplug lock, so we are safe from here on */
399         cpus_and(online_policy_cpus, cpu_online_map, policy->cpus);
400 #else
401         online_policy_cpus = policy->cpus;
402 #endif
403
404         next_perf_state = data->freq_table[next_state].index;
405         if (perf->state == next_perf_state) {
406                 if (unlikely(data->resume)) {
407                         dprintk("Called after resume, resetting to P%d\n",
408                                 next_perf_state);
409                         data->resume = 0;
410                 } else {
411                         dprintk("Already at target state (P%d)\n",
412                                 next_perf_state);
413                         return 0;
414                 }
415         }
416
417         switch (data->cpu_feature) {
418         case SYSTEM_INTEL_MSR_CAPABLE:
419                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
420                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
421                 cmd.val = (u32) perf->states[next_perf_state].control;
422                 break;
423         case SYSTEM_IO_CAPABLE:
424                 cmd.type = SYSTEM_IO_CAPABLE;
425                 cmd.addr.io.port = perf->control_register.address;
426                 cmd.addr.io.bit_width = perf->control_register.bit_width;
427                 cmd.val = (u32) perf->states[next_perf_state].control;
428                 break;
429         default:
430                 return -ENODEV;
431         }
432
433         cpus_clear(cmd.mask);
434
435         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
436                 cmd.mask = online_policy_cpus;
437         else
438                 cpu_set(policy->cpu, cmd.mask);
439
440         freqs.old = perf->states[perf->state].core_frequency * 1000;
441         freqs.new = data->freq_table[next_state].frequency;
442         for_each_cpu_mask(i, cmd.mask) {
443                 freqs.cpu = i;
444                 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
445         }
446
447         drv_write(&cmd);
448
449         if (acpi_pstate_strict) {
450                 if (!check_freqs(cmd.mask, freqs.new, data)) {
451                         dprintk("acpi_cpufreq_target failed (%d)\n",
452                                 policy->cpu);
453                         return -EAGAIN;
454                 }
455         }
456
457         for_each_cpu_mask(i, cmd.mask) {
458                 freqs.cpu = i;
459                 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
460         }
461         perf->state = next_perf_state;
462
463         return result;
464 }
465
466 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
467 {
468         struct acpi_cpufreq_data *data = drv_data[policy->cpu];
469
470         dprintk("acpi_cpufreq_verify\n");
471
472         return cpufreq_frequency_table_verify(policy, data->freq_table);
473 }
474
475 static unsigned long
476 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
477 {
478         struct acpi_processor_performance *perf = data->acpi_data;
479
480         if (cpu_khz) {
481                 /* search the closest match to cpu_khz */
482                 unsigned int i;
483                 unsigned long freq;
484                 unsigned long freqn = perf->states[0].core_frequency * 1000;
485
486                 for (i=0; i<(perf->state_count-1); i++) {
487                         freq = freqn;
488                         freqn = perf->states[i+1].core_frequency * 1000;
489                         if ((2 * cpu_khz) > (freqn + freq)) {
490                                 perf->state = i;
491                                 return freq;
492                         }
493                 }
494                 perf->state = perf->state_count-1;
495                 return freqn;
496         } else {
497                 /* assume CPU is at P0... */
498                 perf->state = 0;
499                 return perf->states[0].core_frequency * 1000;
500         }
501 }
502
503 /*
504  * acpi_cpufreq_early_init - initialize ACPI P-States library
505  *
506  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
507  * in order to determine correct frequency and voltage pairings. We can
508  * do _PDC and _PSD and find out the processor dependency for the
509  * actual init that will happen later...
510  */
511 static int acpi_cpufreq_early_init(void)
512 {
513         struct acpi_processor_performance *data;
514         cpumask_t covered;
515         unsigned int i, j;
516
517         dprintk("acpi_cpufreq_early_init\n");
518
519         for_each_possible_cpu(i) {
520                 data = kzalloc(sizeof(struct acpi_processor_performance),
521                                GFP_KERNEL);
522                 if (!data) {
523                         for_each_cpu_mask(j, covered) {
524                                 kfree(acpi_perf_data[j]);
525                                 acpi_perf_data[j] = NULL;
526                         }
527                         return -ENOMEM;
528                 }
529                 acpi_perf_data[i] = data;
530                 cpu_set(i, covered);
531         }
532
533         /* Do initialization in ACPI core */
534         acpi_processor_preregister_performance(acpi_perf_data);
535         return 0;
536 }
537
538 #ifdef CONFIG_SMP
539 /*
540  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
541  * or do it in BIOS firmware and won't inform about it to OS. If not
542  * detected, this has a side effect of making CPU run at a different speed
543  * than OS intended it to run at. Detect it and handle it cleanly.
544  */
545 static int bios_with_sw_any_bug;
546
547 static int sw_any_bug_found(struct dmi_system_id *d)
548 {
549         bios_with_sw_any_bug = 1;
550         return 0;
551 }
552
553 static struct dmi_system_id sw_any_bug_dmi_table[] = {
554         {
555                 .callback = sw_any_bug_found,
556                 .ident = "Supermicro Server X6DLP",
557                 .matches = {
558                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
559                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
560                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
561                 },
562         },
563         { }
564 };
565 #endif
566
567 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
568 {
569         unsigned int i;
570         unsigned int valid_states = 0;
571         unsigned int cpu = policy->cpu;
572         struct acpi_cpufreq_data *data;
573         unsigned int result = 0;
574         struct cpuinfo_x86 *c = &cpu_data[policy->cpu];
575         struct acpi_processor_performance *perf;
576
577         dprintk("acpi_cpufreq_cpu_init\n");
578
579         if (!acpi_perf_data[cpu])
580                 return -ENODEV;
581
582         data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
583         if (!data)
584                 return -ENOMEM;
585
586         data->acpi_data = acpi_perf_data[cpu];
587         drv_data[cpu] = data;
588
589         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
590                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
591
592         result = acpi_processor_register_performance(data->acpi_data, cpu);
593         if (result)
594                 goto err_free;
595
596         perf = data->acpi_data;
597         policy->shared_type = perf->shared_type;
598
599         /*
600          * Will let policy->cpus know about dependency only when software
601          * coordination is required.
602          */
603         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
604             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
605                 policy->cpus = perf->shared_cpu_map;
606         }
607
608 #ifdef CONFIG_SMP
609         dmi_check_system(sw_any_bug_dmi_table);
610         if (bios_with_sw_any_bug && cpus_weight(policy->cpus) == 1) {
611                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
612                 policy->cpus = cpu_core_map[cpu];
613         }
614 #endif
615
616         /* capability check */
617         if (perf->state_count <= 1) {
618                 dprintk("No P-States\n");
619                 result = -ENODEV;
620                 goto err_unreg;
621         }
622
623         if (perf->control_register.space_id != perf->status_register.space_id) {
624                 result = -ENODEV;
625                 goto err_unreg;
626         }
627
628         switch (perf->control_register.space_id) {
629         case ACPI_ADR_SPACE_SYSTEM_IO:
630                 dprintk("SYSTEM IO addr space\n");
631                 data->cpu_feature = SYSTEM_IO_CAPABLE;
632                 break;
633         case ACPI_ADR_SPACE_FIXED_HARDWARE:
634                 dprintk("HARDWARE addr space\n");
635                 if (!check_est_cpu(cpu)) {
636                         result = -ENODEV;
637                         goto err_unreg;
638                 }
639                 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
640                 break;
641         default:
642                 dprintk("Unknown addr space %d\n",
643                         (u32) (perf->control_register.space_id));
644                 result = -ENODEV;
645                 goto err_unreg;
646         }
647
648         data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
649                     (perf->state_count+1), GFP_KERNEL);
650         if (!data->freq_table) {
651                 result = -ENOMEM;
652                 goto err_unreg;
653         }
654
655         /* detect transition latency */
656         policy->cpuinfo.transition_latency = 0;
657         for (i=0; i<perf->state_count; i++) {
658                 if ((perf->states[i].transition_latency * 1000) >
659                     policy->cpuinfo.transition_latency)
660                         policy->cpuinfo.transition_latency =
661                             perf->states[i].transition_latency * 1000;
662         }
663         policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
664
665         data->max_freq = perf->states[0].core_frequency * 1000;
666         /* table init */
667         for (i=0; i<perf->state_count; i++) {
668                 if (i>0 && perf->states[i].core_frequency ==
669                     perf->states[i-1].core_frequency)
670                         continue;
671
672                 data->freq_table[valid_states].index = i;
673                 data->freq_table[valid_states].frequency =
674                     perf->states[i].core_frequency * 1000;
675                 valid_states++;
676         }
677         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
678         perf->state = 0;
679
680         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
681         if (result)
682                 goto err_freqfree;
683
684         switch (perf->control_register.space_id) {
685         case ACPI_ADR_SPACE_SYSTEM_IO:
686                 /* Current speed is unknown and not detectable by IO port */
687                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
688                 break;
689         case ACPI_ADR_SPACE_FIXED_HARDWARE:
690                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
691                 policy->cur = get_cur_freq_on_cpu(cpu);
692                 break;
693         default:
694                 break;
695         }
696
697         /* notify BIOS that we exist */
698         acpi_processor_notify_smm(THIS_MODULE);
699
700         /* Check for APERF/MPERF support in hardware */
701         if (c->x86_vendor == X86_VENDOR_INTEL && c->cpuid_level >= 6) {
702                 unsigned int ecx;
703                 ecx = cpuid_ecx(6);
704                 if (ecx & CPUID_6_ECX_APERFMPERF_CAPABILITY)
705                         acpi_cpufreq_driver.getavg = get_measured_perf;
706         }
707
708         dprintk("CPU%u - ACPI performance management activated.\n", cpu);
709         for (i = 0; i < perf->state_count; i++)
710                 dprintk("     %cP%d: %d MHz, %d mW, %d uS\n",
711                         (i == perf->state ? '*' : ' '), i,
712                         (u32) perf->states[i].core_frequency,
713                         (u32) perf->states[i].power,
714                         (u32) perf->states[i].transition_latency);
715
716         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
717
718         /*
719          * the first call to ->target() should result in us actually
720          * writing something to the appropriate registers.
721          */
722         data->resume = 1;
723
724         return result;
725
726 err_freqfree:
727         kfree(data->freq_table);
728 err_unreg:
729         acpi_processor_unregister_performance(perf, cpu);
730 err_free:
731         kfree(data);
732         drv_data[cpu] = NULL;
733
734         return result;
735 }
736
737 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
738 {
739         struct acpi_cpufreq_data *data = drv_data[policy->cpu];
740
741         dprintk("acpi_cpufreq_cpu_exit\n");
742
743         if (data) {
744                 cpufreq_frequency_table_put_attr(policy->cpu);
745                 drv_data[policy->cpu] = NULL;
746                 acpi_processor_unregister_performance(data->acpi_data,
747                                                       policy->cpu);
748                 kfree(data);
749         }
750
751         return 0;
752 }
753
754 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
755 {
756         struct acpi_cpufreq_data *data = drv_data[policy->cpu];
757
758         dprintk("acpi_cpufreq_resume\n");
759
760         data->resume = 1;
761
762         return 0;
763 }
764
765 static struct freq_attr *acpi_cpufreq_attr[] = {
766         &cpufreq_freq_attr_scaling_available_freqs,
767         NULL,
768 };
769
770 static struct cpufreq_driver acpi_cpufreq_driver = {
771         .verify = acpi_cpufreq_verify,
772         .target = acpi_cpufreq_target,
773         .init = acpi_cpufreq_cpu_init,
774         .exit = acpi_cpufreq_cpu_exit,
775         .resume = acpi_cpufreq_resume,
776         .name = "acpi-cpufreq",
777         .owner = THIS_MODULE,
778         .attr = acpi_cpufreq_attr,
779 };
780
781 static int __init acpi_cpufreq_init(void)
782 {
783         dprintk("acpi_cpufreq_init\n");
784
785         acpi_cpufreq_early_init();
786
787         return cpufreq_register_driver(&acpi_cpufreq_driver);
788 }
789
790 static void __exit acpi_cpufreq_exit(void)
791 {
792         unsigned int i;
793         dprintk("acpi_cpufreq_exit\n");
794
795         cpufreq_unregister_driver(&acpi_cpufreq_driver);
796
797         for_each_possible_cpu(i) {
798                 kfree(acpi_perf_data[i]);
799                 acpi_perf_data[i] = NULL;
800         }
801         return;
802 }
803
804 module_param(acpi_pstate_strict, uint, 0644);
805 MODULE_PARM_DESC(acpi_pstate_strict,
806         "value 0 or non-zero. non-zero -> strict ACPI checks are "
807         "performed during frequency changes.");
808
809 late_initcall(acpi_cpufreq_init);
810 module_exit(acpi_cpufreq_exit);
811
812 MODULE_ALIAS("acpi");