Merge phase #3 (IOMMU) of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux...
[linux-2.6] / arch / x86 / 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 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_ptr(current, &cmd->mask);
196         do_drv_read(cmd);
197         set_cpus_allowed_ptr(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_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
214 static 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  * 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(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                 /* We were not able to run on requested processor */
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          * We dont want to do 64 bit divide with 32 bit kernel
291          * Get an approximate value. Return failure in case we cannot get
292          * an approximate value.
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
339 static 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                  * The dreaded BIOS frequency change behind our back.
357                  * Force set the frequency on next target call.
358                  */
359                 data->resume = 1;
360         }
361
362         dprintk("cur freq = %u\n", freq);
363
364         return freq;
365 }
366
367 static 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
382 static 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; /* Index into freq_table */
391         unsigned int next_perf_state = 0; /* Index into perf table */
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         /* cpufreq holds the hotplug lock, so we are safe from here on */
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
479 static 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
488 static unsigned long
489 acpi_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                 /* search the closest match to cpu_khz */
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                 /* assume CPU is at P0... */
511                 perf->state = 0;
512                 return perf->states[0].core_frequency * 1000;
513         }
514 }
515
516 /*
517  * acpi_cpufreq_early_init - initialize ACPI P-States library
518  *
519  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
520  * in order to determine correct frequency and voltage pairings. We can
521  * do _PDC and _PSD and find out the processor dependency for the
522  * actual init that will happen later...
523  */
524 static 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         /* Do initialization in ACPI core */
535         acpi_processor_preregister_performance(acpi_perf_data);
536         return 0;
537 }
538
539 #ifdef CONFIG_SMP
540 /*
541  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
542  * or do it in BIOS firmware and won't inform about it to OS. If not
543  * detected, this has a side effect of making CPU run at a different speed
544  * than OS intended it to run at. Detect it and handle it cleanly.
545  */
546 static int bios_with_sw_any_bug;
547
548 static int sw_any_bug_found(const struct dmi_system_id *d)
549 {
550         bios_with_sw_any_bug = 1;
551         return 0;
552 }
553
554 static 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
568 static 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          * Will let policy->cpus know about dependency only when software
599          * coordination is required.
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         /* capability check */
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         /* detect transition latency */
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         /* table init */
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                 /* Current speed is unknown and not detectable by IO port */
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         /* notify BIOS that we exist */
696         acpi_processor_notify_smm(THIS_MODULE);
697
698         /* Check for APERF/MPERF support in hardware */
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          * the first call to ->target() should result in us actually
718          * writing something to the appropriate registers.
719          */
720         data->resume = 1;
721
722         return result;
723
724 err_freqfree:
725         kfree(data->freq_table);
726 err_unreg:
727         acpi_processor_unregister_performance(perf, cpu);
728 err_free:
729         kfree(data);
730         per_cpu(drv_data, cpu) = NULL;
731
732         return result;
733 }
734
735 static 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
752 static 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
763 static struct freq_attr *acpi_cpufreq_attr[] = {
764         &cpufreq_freq_attr_scaling_available_freqs,
765         NULL,
766 };
767
768 static 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
779 static int __init acpi_cpufreq_init(void)
780 {
781         int ret;
782
783         dprintk("acpi_cpufreq_init\n");
784
785         ret = acpi_cpufreq_early_init();
786         if (ret)
787                 return ret;
788
789         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
790         if (ret)
791                 free_percpu(acpi_perf_data);
792
793         return ret;
794 }
795
796 static void __exit acpi_cpufreq_exit(void)
797 {
798         dprintk("acpi_cpufreq_exit\n");
799
800         cpufreq_unregister_driver(&acpi_cpufreq_driver);
801
802         free_percpu(acpi_perf_data);
803 }
804
805 module_param(acpi_pstate_strict, uint, 0644);
806 MODULE_PARM_DESC(acpi_pstate_strict,
807         "value 0 or non-zero. non-zero -> strict ACPI checks are "
808         "performed during frequency changes.");
809
810 late_initcall(acpi_cpufreq_init);
811 module_exit(acpi_cpufreq_exit);
812
813 MODULE_ALIAS("acpi");