acpi-cpufreq: Fail initialization if driver cannot be registered
[sfrench/cifs-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
49 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
50 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
51 MODULE_LICENSE("GPL");
52
53 #define PFX "acpi-cpufreq: "
54
55 enum {
56         UNDEFINED_CAPABLE = 0,
57         SYSTEM_INTEL_MSR_CAPABLE,
58         SYSTEM_AMD_MSR_CAPABLE,
59         SYSTEM_IO_CAPABLE,
60 };
61
62 #define INTEL_MSR_RANGE         (0xffff)
63 #define AMD_MSR_RANGE           (0x7)
64
65 #define MSR_K7_HWCR_CPB_DIS     (1ULL << 25)
66
67 struct acpi_cpufreq_data {
68         struct acpi_processor_performance *acpi_data;
69         struct cpufreq_frequency_table *freq_table;
70         unsigned int resume;
71         unsigned int cpu_feature;
72         cpumask_var_t freqdomain_cpus;
73 };
74
75 static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
76
77 /* acpi_perf_data is a pointer to percpu data. */
78 static struct acpi_processor_performance __percpu *acpi_perf_data;
79
80 static struct cpufreq_driver acpi_cpufreq_driver;
81
82 static unsigned int acpi_pstate_strict;
83 static bool boost_enabled, boost_supported;
84 static struct msr __percpu *msrs;
85
86 static bool boost_state(unsigned int cpu)
87 {
88         u32 lo, hi;
89         u64 msr;
90
91         switch (boot_cpu_data.x86_vendor) {
92         case X86_VENDOR_INTEL:
93                 rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
94                 msr = lo | ((u64)hi << 32);
95                 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
96         case X86_VENDOR_AMD:
97                 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
98                 msr = lo | ((u64)hi << 32);
99                 return !(msr & MSR_K7_HWCR_CPB_DIS);
100         }
101         return false;
102 }
103
104 static void boost_set_msrs(bool enable, const struct cpumask *cpumask)
105 {
106         u32 cpu;
107         u32 msr_addr;
108         u64 msr_mask;
109
110         switch (boot_cpu_data.x86_vendor) {
111         case X86_VENDOR_INTEL:
112                 msr_addr = MSR_IA32_MISC_ENABLE;
113                 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
114                 break;
115         case X86_VENDOR_AMD:
116                 msr_addr = MSR_K7_HWCR;
117                 msr_mask = MSR_K7_HWCR_CPB_DIS;
118                 break;
119         default:
120                 return;
121         }
122
123         rdmsr_on_cpus(cpumask, msr_addr, msrs);
124
125         for_each_cpu(cpu, cpumask) {
126                 struct msr *reg = per_cpu_ptr(msrs, cpu);
127                 if (enable)
128                         reg->q &= ~msr_mask;
129                 else
130                         reg->q |= msr_mask;
131         }
132
133         wrmsr_on_cpus(cpumask, msr_addr, msrs);
134 }
135
136 static ssize_t _store_boost(const char *buf, size_t count)
137 {
138         int ret;
139         unsigned long val = 0;
140
141         if (!boost_supported)
142                 return -EINVAL;
143
144         ret = kstrtoul(buf, 10, &val);
145         if (ret || (val > 1))
146                 return -EINVAL;
147
148         if ((val && boost_enabled) || (!val && !boost_enabled))
149                 return count;
150
151         get_online_cpus();
152
153         boost_set_msrs(val, cpu_online_mask);
154
155         put_online_cpus();
156
157         boost_enabled = val;
158         pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
159
160         return count;
161 }
162
163 static ssize_t store_global_boost(struct kobject *kobj, struct attribute *attr,
164                                   const char *buf, size_t count)
165 {
166         return _store_boost(buf, count);
167 }
168
169 static ssize_t show_global_boost(struct kobject *kobj,
170                                  struct attribute *attr, char *buf)
171 {
172         return sprintf(buf, "%u\n", boost_enabled);
173 }
174
175 static struct global_attr global_boost = __ATTR(boost, 0644,
176                                                 show_global_boost,
177                                                 store_global_boost);
178
179 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
180 {
181         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
182
183         return cpufreq_show_cpus(data->freqdomain_cpus, buf);
184 }
185
186 cpufreq_freq_attr_ro(freqdomain_cpus);
187
188 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
189 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
190                          size_t count)
191 {
192         return _store_boost(buf, count);
193 }
194
195 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
196 {
197         return sprintf(buf, "%u\n", boost_enabled);
198 }
199
200 cpufreq_freq_attr_rw(cpb);
201 #endif
202
203 static int check_est_cpu(unsigned int cpuid)
204 {
205         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
206
207         return cpu_has(cpu, X86_FEATURE_EST);
208 }
209
210 static int check_amd_hwpstate_cpu(unsigned int cpuid)
211 {
212         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
213
214         return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
215 }
216
217 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
218 {
219         struct acpi_processor_performance *perf;
220         int i;
221
222         perf = data->acpi_data;
223
224         for (i = 0; i < perf->state_count; i++) {
225                 if (value == perf->states[i].status)
226                         return data->freq_table[i].frequency;
227         }
228         return 0;
229 }
230
231 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
232 {
233         int i;
234         struct acpi_processor_performance *perf;
235
236         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
237                 msr &= AMD_MSR_RANGE;
238         else
239                 msr &= INTEL_MSR_RANGE;
240
241         perf = data->acpi_data;
242
243         for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
244                 if (msr == perf->states[data->freq_table[i].driver_data].status)
245                         return data->freq_table[i].frequency;
246         }
247         return data->freq_table[0].frequency;
248 }
249
250 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
251 {
252         switch (data->cpu_feature) {
253         case SYSTEM_INTEL_MSR_CAPABLE:
254         case SYSTEM_AMD_MSR_CAPABLE:
255                 return extract_msr(val, data);
256         case SYSTEM_IO_CAPABLE:
257                 return extract_io(val, data);
258         default:
259                 return 0;
260         }
261 }
262
263 struct msr_addr {
264         u32 reg;
265 };
266
267 struct io_addr {
268         u16 port;
269         u8 bit_width;
270 };
271
272 struct drv_cmd {
273         unsigned int type;
274         const struct cpumask *mask;
275         union {
276                 struct msr_addr msr;
277                 struct io_addr io;
278         } addr;
279         u32 val;
280 };
281
282 /* Called via smp_call_function_single(), on the target CPU */
283 static void do_drv_read(void *_cmd)
284 {
285         struct drv_cmd *cmd = _cmd;
286         u32 h;
287
288         switch (cmd->type) {
289         case SYSTEM_INTEL_MSR_CAPABLE:
290         case SYSTEM_AMD_MSR_CAPABLE:
291                 rdmsr(cmd->addr.msr.reg, cmd->val, h);
292                 break;
293         case SYSTEM_IO_CAPABLE:
294                 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
295                                 &cmd->val,
296                                 (u32)cmd->addr.io.bit_width);
297                 break;
298         default:
299                 break;
300         }
301 }
302
303 /* Called via smp_call_function_many(), on the target CPUs */
304 static void do_drv_write(void *_cmd)
305 {
306         struct drv_cmd *cmd = _cmd;
307         u32 lo, hi;
308
309         switch (cmd->type) {
310         case SYSTEM_INTEL_MSR_CAPABLE:
311                 rdmsr(cmd->addr.msr.reg, lo, hi);
312                 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
313                 wrmsr(cmd->addr.msr.reg, lo, hi);
314                 break;
315         case SYSTEM_AMD_MSR_CAPABLE:
316                 wrmsr(cmd->addr.msr.reg, cmd->val, 0);
317                 break;
318         case SYSTEM_IO_CAPABLE:
319                 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
320                                 cmd->val,
321                                 (u32)cmd->addr.io.bit_width);
322                 break;
323         default:
324                 break;
325         }
326 }
327
328 static void drv_read(struct drv_cmd *cmd)
329 {
330         int err;
331         cmd->val = 0;
332
333         err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
334         WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
335 }
336
337 static void drv_write(struct drv_cmd *cmd)
338 {
339         int this_cpu;
340
341         this_cpu = get_cpu();
342         if (cpumask_test_cpu(this_cpu, cmd->mask))
343                 do_drv_write(cmd);
344         smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
345         put_cpu();
346 }
347
348 static u32 get_cur_val(const struct cpumask *mask)
349 {
350         struct acpi_processor_performance *perf;
351         struct drv_cmd cmd;
352
353         if (unlikely(cpumask_empty(mask)))
354                 return 0;
355
356         switch (per_cpu(acfreq_data, cpumask_first(mask))->cpu_feature) {
357         case SYSTEM_INTEL_MSR_CAPABLE:
358                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
359                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
360                 break;
361         case SYSTEM_AMD_MSR_CAPABLE:
362                 cmd.type = SYSTEM_AMD_MSR_CAPABLE;
363                 cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
364                 break;
365         case SYSTEM_IO_CAPABLE:
366                 cmd.type = SYSTEM_IO_CAPABLE;
367                 perf = per_cpu(acfreq_data, cpumask_first(mask))->acpi_data;
368                 cmd.addr.io.port = perf->control_register.address;
369                 cmd.addr.io.bit_width = perf->control_register.bit_width;
370                 break;
371         default:
372                 return 0;
373         }
374
375         cmd.mask = mask;
376         drv_read(&cmd);
377
378         pr_debug("get_cur_val = %u\n", cmd.val);
379
380         return cmd.val;
381 }
382
383 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
384 {
385         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu);
386         unsigned int freq;
387         unsigned int cached_freq;
388
389         pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
390
391         if (unlikely(data == NULL ||
392                      data->acpi_data == NULL || data->freq_table == NULL)) {
393                 return 0;
394         }
395
396         cached_freq = data->freq_table[data->acpi_data->state].frequency;
397         freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
398         if (freq != cached_freq) {
399                 /*
400                  * The dreaded BIOS frequency change behind our back.
401                  * Force set the frequency on next target call.
402                  */
403                 data->resume = 1;
404         }
405
406         pr_debug("cur freq = %u\n", freq);
407
408         return freq;
409 }
410
411 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
412                                 struct acpi_cpufreq_data *data)
413 {
414         unsigned int cur_freq;
415         unsigned int i;
416
417         for (i = 0; i < 100; i++) {
418                 cur_freq = extract_freq(get_cur_val(mask), data);
419                 if (cur_freq == freq)
420                         return 1;
421                 udelay(10);
422         }
423         return 0;
424 }
425
426 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
427                                unsigned int target_freq, unsigned int relation)
428 {
429         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
430         struct acpi_processor_performance *perf;
431         struct cpufreq_freqs freqs;
432         struct drv_cmd cmd;
433         unsigned int next_state = 0; /* Index into freq_table */
434         unsigned int next_perf_state = 0; /* Index into perf table */
435         int result = 0;
436
437         pr_debug("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
438
439         if (unlikely(data == NULL ||
440              data->acpi_data == NULL || data->freq_table == NULL)) {
441                 return -ENODEV;
442         }
443
444         perf = data->acpi_data;
445         result = cpufreq_frequency_table_target(policy,
446                                                 data->freq_table,
447                                                 target_freq,
448                                                 relation, &next_state);
449         if (unlikely(result)) {
450                 result = -ENODEV;
451                 goto out;
452         }
453
454         next_perf_state = data->freq_table[next_state].driver_data;
455         if (perf->state == next_perf_state) {
456                 if (unlikely(data->resume)) {
457                         pr_debug("Called after resume, resetting to P%d\n",
458                                 next_perf_state);
459                         data->resume = 0;
460                 } else {
461                         pr_debug("Already at target state (P%d)\n",
462                                 next_perf_state);
463                         goto out;
464                 }
465         }
466
467         switch (data->cpu_feature) {
468         case SYSTEM_INTEL_MSR_CAPABLE:
469                 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
470                 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
471                 cmd.val = (u32) perf->states[next_perf_state].control;
472                 break;
473         case SYSTEM_AMD_MSR_CAPABLE:
474                 cmd.type = SYSTEM_AMD_MSR_CAPABLE;
475                 cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
476                 cmd.val = (u32) perf->states[next_perf_state].control;
477                 break;
478         case SYSTEM_IO_CAPABLE:
479                 cmd.type = SYSTEM_IO_CAPABLE;
480                 cmd.addr.io.port = perf->control_register.address;
481                 cmd.addr.io.bit_width = perf->control_register.bit_width;
482                 cmd.val = (u32) perf->states[next_perf_state].control;
483                 break;
484         default:
485                 result = -ENODEV;
486                 goto out;
487         }
488
489         /* cpufreq holds the hotplug lock, so we are safe from here on */
490         if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
491                 cmd.mask = policy->cpus;
492         else
493                 cmd.mask = cpumask_of(policy->cpu);
494
495         freqs.old = perf->states[perf->state].core_frequency * 1000;
496         freqs.new = data->freq_table[next_state].frequency;
497         cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
498
499         drv_write(&cmd);
500
501         if (acpi_pstate_strict) {
502                 if (!check_freqs(cmd.mask, freqs.new, data)) {
503                         pr_debug("acpi_cpufreq_target failed (%d)\n",
504                                 policy->cpu);
505                         result = -EAGAIN;
506                         freqs.new = freqs.old;
507                 }
508         }
509
510         cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
511
512         if (!result)
513                 perf->state = next_perf_state;
514
515 out:
516         return result;
517 }
518
519 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
520 {
521         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
522
523         pr_debug("acpi_cpufreq_verify\n");
524
525         return cpufreq_frequency_table_verify(policy, data->freq_table);
526 }
527
528 static unsigned long
529 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
530 {
531         struct acpi_processor_performance *perf = data->acpi_data;
532
533         if (cpu_khz) {
534                 /* search the closest match to cpu_khz */
535                 unsigned int i;
536                 unsigned long freq;
537                 unsigned long freqn = perf->states[0].core_frequency * 1000;
538
539                 for (i = 0; i < (perf->state_count-1); i++) {
540                         freq = freqn;
541                         freqn = perf->states[i+1].core_frequency * 1000;
542                         if ((2 * cpu_khz) > (freqn + freq)) {
543                                 perf->state = i;
544                                 return freq;
545                         }
546                 }
547                 perf->state = perf->state_count-1;
548                 return freqn;
549         } else {
550                 /* assume CPU is at P0... */
551                 perf->state = 0;
552                 return perf->states[0].core_frequency * 1000;
553         }
554 }
555
556 static void free_acpi_perf_data(void)
557 {
558         unsigned int i;
559
560         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
561         for_each_possible_cpu(i)
562                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
563                                  ->shared_cpu_map);
564         free_percpu(acpi_perf_data);
565 }
566
567 static int boost_notify(struct notifier_block *nb, unsigned long action,
568                       void *hcpu)
569 {
570         unsigned cpu = (long)hcpu;
571         const struct cpumask *cpumask;
572
573         cpumask = get_cpu_mask(cpu);
574
575         /*
576          * Clear the boost-disable bit on the CPU_DOWN path so that
577          * this cpu cannot block the remaining ones from boosting. On
578          * the CPU_UP path we simply keep the boost-disable flag in
579          * sync with the current global state.
580          */
581
582         switch (action) {
583         case CPU_UP_PREPARE:
584         case CPU_UP_PREPARE_FROZEN:
585                 boost_set_msrs(boost_enabled, cpumask);
586                 break;
587
588         case CPU_DOWN_PREPARE:
589         case CPU_DOWN_PREPARE_FROZEN:
590                 boost_set_msrs(1, cpumask);
591                 break;
592
593         default:
594                 break;
595         }
596
597         return NOTIFY_OK;
598 }
599
600
601 static struct notifier_block boost_nb = {
602         .notifier_call          = boost_notify,
603 };
604
605 /*
606  * acpi_cpufreq_early_init - initialize ACPI P-States library
607  *
608  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
609  * in order to determine correct frequency and voltage pairings. We can
610  * do _PDC and _PSD and find out the processor dependency for the
611  * actual init that will happen later...
612  */
613 static int __init acpi_cpufreq_early_init(void)
614 {
615         unsigned int i;
616         pr_debug("acpi_cpufreq_early_init\n");
617
618         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
619         if (!acpi_perf_data) {
620                 pr_debug("Memory allocation error for acpi_perf_data.\n");
621                 return -ENOMEM;
622         }
623         for_each_possible_cpu(i) {
624                 if (!zalloc_cpumask_var_node(
625                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
626                         GFP_KERNEL, cpu_to_node(i))) {
627
628                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
629                         free_acpi_perf_data();
630                         return -ENOMEM;
631                 }
632         }
633
634         /* Do initialization in ACPI core */
635         acpi_processor_preregister_performance(acpi_perf_data);
636         return 0;
637 }
638
639 #ifdef CONFIG_SMP
640 /*
641  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
642  * or do it in BIOS firmware and won't inform about it to OS. If not
643  * detected, this has a side effect of making CPU run at a different speed
644  * than OS intended it to run at. Detect it and handle it cleanly.
645  */
646 static int bios_with_sw_any_bug;
647
648 static int sw_any_bug_found(const struct dmi_system_id *d)
649 {
650         bios_with_sw_any_bug = 1;
651         return 0;
652 }
653
654 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
655         {
656                 .callback = sw_any_bug_found,
657                 .ident = "Supermicro Server X6DLP",
658                 .matches = {
659                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
660                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
661                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
662                 },
663         },
664         { }
665 };
666
667 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
668 {
669         /* Intel Xeon Processor 7100 Series Specification Update
670          * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
671          * AL30: A Machine Check Exception (MCE) Occurring during an
672          * Enhanced Intel SpeedStep Technology Ratio Change May Cause
673          * Both Processor Cores to Lock Up. */
674         if (c->x86_vendor == X86_VENDOR_INTEL) {
675                 if ((c->x86 == 15) &&
676                     (c->x86_model == 6) &&
677                     (c->x86_mask == 8)) {
678                         printk(KERN_INFO "acpi-cpufreq: Intel(R) "
679                             "Xeon(R) 7100 Errata AL30, processors may "
680                             "lock up on frequency changes: disabling "
681                             "acpi-cpufreq.\n");
682                         return -ENODEV;
683                     }
684                 }
685         return 0;
686 }
687 #endif
688
689 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
690 {
691         unsigned int i;
692         unsigned int valid_states = 0;
693         unsigned int cpu = policy->cpu;
694         struct acpi_cpufreq_data *data;
695         unsigned int result = 0;
696         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
697         struct acpi_processor_performance *perf;
698 #ifdef CONFIG_SMP
699         static int blacklisted;
700 #endif
701
702         pr_debug("acpi_cpufreq_cpu_init\n");
703
704 #ifdef CONFIG_SMP
705         if (blacklisted)
706                 return blacklisted;
707         blacklisted = acpi_cpufreq_blacklist(c);
708         if (blacklisted)
709                 return blacklisted;
710 #endif
711
712         data = kzalloc(sizeof(*data), GFP_KERNEL);
713         if (!data)
714                 return -ENOMEM;
715
716         if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
717                 result = -ENOMEM;
718                 goto err_free;
719         }
720
721         data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
722         per_cpu(acfreq_data, cpu) = data;
723
724         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
725                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
726
727         result = acpi_processor_register_performance(data->acpi_data, cpu);
728         if (result)
729                 goto err_free_mask;
730
731         perf = data->acpi_data;
732         policy->shared_type = perf->shared_type;
733
734         /*
735          * Will let policy->cpus know about dependency only when software
736          * coordination is required.
737          */
738         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
739             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
740                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
741         }
742         cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
743
744 #ifdef CONFIG_SMP
745         dmi_check_system(sw_any_bug_dmi_table);
746         if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
747                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
748                 cpumask_copy(policy->cpus, cpu_core_mask(cpu));
749         }
750
751         if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
752                 cpumask_clear(policy->cpus);
753                 cpumask_set_cpu(cpu, policy->cpus);
754                 cpumask_copy(data->freqdomain_cpus, cpu_sibling_mask(cpu));
755                 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
756                 pr_info_once(PFX "overriding BIOS provided _PSD data\n");
757         }
758 #endif
759
760         /* capability check */
761         if (perf->state_count <= 1) {
762                 pr_debug("No P-States\n");
763                 result = -ENODEV;
764                 goto err_unreg;
765         }
766
767         if (perf->control_register.space_id != perf->status_register.space_id) {
768                 result = -ENODEV;
769                 goto err_unreg;
770         }
771
772         switch (perf->control_register.space_id) {
773         case ACPI_ADR_SPACE_SYSTEM_IO:
774                 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
775                     boot_cpu_data.x86 == 0xf) {
776                         pr_debug("AMD K8 systems must use native drivers.\n");
777                         result = -ENODEV;
778                         goto err_unreg;
779                 }
780                 pr_debug("SYSTEM IO addr space\n");
781                 data->cpu_feature = SYSTEM_IO_CAPABLE;
782                 break;
783         case ACPI_ADR_SPACE_FIXED_HARDWARE:
784                 pr_debug("HARDWARE addr space\n");
785                 if (check_est_cpu(cpu)) {
786                         data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
787                         break;
788                 }
789                 if (check_amd_hwpstate_cpu(cpu)) {
790                         data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
791                         break;
792                 }
793                 result = -ENODEV;
794                 goto err_unreg;
795         default:
796                 pr_debug("Unknown addr space %d\n",
797                         (u32) (perf->control_register.space_id));
798                 result = -ENODEV;
799                 goto err_unreg;
800         }
801
802         data->freq_table = kmalloc(sizeof(*data->freq_table) *
803                     (perf->state_count+1), GFP_KERNEL);
804         if (!data->freq_table) {
805                 result = -ENOMEM;
806                 goto err_unreg;
807         }
808
809         /* detect transition latency */
810         policy->cpuinfo.transition_latency = 0;
811         for (i = 0; i < perf->state_count; i++) {
812                 if ((perf->states[i].transition_latency * 1000) >
813                     policy->cpuinfo.transition_latency)
814                         policy->cpuinfo.transition_latency =
815                             perf->states[i].transition_latency * 1000;
816         }
817
818         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
819         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
820             policy->cpuinfo.transition_latency > 20 * 1000) {
821                 policy->cpuinfo.transition_latency = 20 * 1000;
822                 printk_once(KERN_INFO
823                             "P-state transition latency capped at 20 uS\n");
824         }
825
826         /* table init */
827         for (i = 0; i < perf->state_count; i++) {
828                 if (i > 0 && perf->states[i].core_frequency >=
829                     data->freq_table[valid_states-1].frequency / 1000)
830                         continue;
831
832                 data->freq_table[valid_states].driver_data = i;
833                 data->freq_table[valid_states].frequency =
834                     perf->states[i].core_frequency * 1000;
835                 valid_states++;
836         }
837         data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
838         perf->state = 0;
839
840         result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
841         if (result)
842                 goto err_freqfree;
843
844         if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
845                 printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
846
847         switch (perf->control_register.space_id) {
848         case ACPI_ADR_SPACE_SYSTEM_IO:
849                 /* Current speed is unknown and not detectable by IO port */
850                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
851                 break;
852         case ACPI_ADR_SPACE_FIXED_HARDWARE:
853                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
854                 policy->cur = get_cur_freq_on_cpu(cpu);
855                 break;
856         default:
857                 break;
858         }
859
860         /* notify BIOS that we exist */
861         acpi_processor_notify_smm(THIS_MODULE);
862
863         pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
864         for (i = 0; i < perf->state_count; i++)
865                 pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
866                         (i == perf->state ? '*' : ' '), i,
867                         (u32) perf->states[i].core_frequency,
868                         (u32) perf->states[i].power,
869                         (u32) perf->states[i].transition_latency);
870
871         cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
872
873         /*
874          * the first call to ->target() should result in us actually
875          * writing something to the appropriate registers.
876          */
877         data->resume = 1;
878
879         return result;
880
881 err_freqfree:
882         kfree(data->freq_table);
883 err_unreg:
884         acpi_processor_unregister_performance(perf, cpu);
885 err_free_mask:
886         free_cpumask_var(data->freqdomain_cpus);
887 err_free:
888         kfree(data);
889         per_cpu(acfreq_data, cpu) = NULL;
890
891         return result;
892 }
893
894 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
895 {
896         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
897
898         pr_debug("acpi_cpufreq_cpu_exit\n");
899
900         if (data) {
901                 cpufreq_frequency_table_put_attr(policy->cpu);
902                 per_cpu(acfreq_data, policy->cpu) = NULL;
903                 acpi_processor_unregister_performance(data->acpi_data,
904                                                       policy->cpu);
905                 free_cpumask_var(data->freqdomain_cpus);
906                 kfree(data->freq_table);
907                 kfree(data);
908         }
909
910         return 0;
911 }
912
913 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
914 {
915         struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
916
917         pr_debug("acpi_cpufreq_resume\n");
918
919         data->resume = 1;
920
921         return 0;
922 }
923
924 static struct freq_attr *acpi_cpufreq_attr[] = {
925         &cpufreq_freq_attr_scaling_available_freqs,
926         &freqdomain_cpus,
927         NULL,   /* this is a placeholder for cpb, do not remove */
928         NULL,
929 };
930
931 static struct cpufreq_driver acpi_cpufreq_driver = {
932         .verify         = acpi_cpufreq_verify,
933         .target         = acpi_cpufreq_target,
934         .bios_limit     = acpi_processor_get_bios_limit,
935         .init           = acpi_cpufreq_cpu_init,
936         .exit           = acpi_cpufreq_cpu_exit,
937         .resume         = acpi_cpufreq_resume,
938         .name           = "acpi-cpufreq",
939         .attr           = acpi_cpufreq_attr,
940 };
941
942 static void __init acpi_cpufreq_boost_init(void)
943 {
944         if (boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)) {
945                 msrs = msrs_alloc();
946
947                 if (!msrs)
948                         return;
949
950                 boost_supported = true;
951                 boost_enabled = boost_state(0);
952
953                 get_online_cpus();
954
955                 /* Force all MSRs to the same value */
956                 boost_set_msrs(boost_enabled, cpu_online_mask);
957
958                 register_cpu_notifier(&boost_nb);
959
960                 put_online_cpus();
961         } else
962                 global_boost.attr.mode = 0444;
963
964         /* We create the boost file in any case, though for systems without
965          * hardware support it will be read-only and hardwired to return 0.
966          */
967         if (cpufreq_sysfs_create_file(&(global_boost.attr)))
968                 pr_warn(PFX "could not register global boost sysfs file\n");
969         else
970                 pr_debug("registered global boost sysfs file\n");
971 }
972
973 static void __exit acpi_cpufreq_boost_exit(void)
974 {
975         cpufreq_sysfs_remove_file(&(global_boost.attr));
976
977         if (msrs) {
978                 unregister_cpu_notifier(&boost_nb);
979
980                 msrs_free(msrs);
981                 msrs = NULL;
982         }
983 }
984
985 static int __init acpi_cpufreq_init(void)
986 {
987         int ret;
988
989         if (acpi_disabled)
990                 return -ENODEV;
991
992         /* don't keep reloading if cpufreq_driver exists */
993         if (cpufreq_get_current_driver())
994                 return -EEXIST;
995
996         pr_debug("acpi_cpufreq_init\n");
997
998         ret = acpi_cpufreq_early_init();
999         if (ret)
1000                 return ret;
1001
1002 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
1003         /* this is a sysfs file with a strange name and an even stranger
1004          * semantic - per CPU instantiation, but system global effect.
1005          * Lets enable it only on AMD CPUs for compatibility reasons and
1006          * only if configured. This is considered legacy code, which
1007          * will probably be removed at some point in the future.
1008          */
1009         if (check_amd_hwpstate_cpu(0)) {
1010                 struct freq_attr **iter;
1011
1012                 pr_debug("adding sysfs entry for cpb\n");
1013
1014                 for (iter = acpi_cpufreq_attr; *iter != NULL; iter++)
1015                         ;
1016
1017                 /* make sure there is a terminator behind it */
1018                 if (iter[1] == NULL)
1019                         *iter = &cpb;
1020         }
1021 #endif
1022
1023         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
1024         if (ret)
1025                 free_acpi_perf_data();
1026         else
1027                 acpi_cpufreq_boost_init();
1028
1029         return ret;
1030 }
1031
1032 static void __exit acpi_cpufreq_exit(void)
1033 {
1034         pr_debug("acpi_cpufreq_exit\n");
1035
1036         acpi_cpufreq_boost_exit();
1037
1038         cpufreq_unregister_driver(&acpi_cpufreq_driver);
1039
1040         free_acpi_perf_data();
1041 }
1042
1043 module_param(acpi_pstate_strict, uint, 0644);
1044 MODULE_PARM_DESC(acpi_pstate_strict,
1045         "value 0 or non-zero. non-zero -> strict ACPI checks are "
1046         "performed during frequency changes.");
1047
1048 late_initcall(acpi_cpufreq_init);
1049 module_exit(acpi_cpufreq_exit);
1050
1051 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
1052         X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1053         X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1054         {}
1055 };
1056 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1057
1058 static const struct acpi_device_id processor_device_ids[] = {
1059         {ACPI_PROCESSOR_OBJECT_HID, },
1060         {ACPI_PROCESSOR_DEVICE_HID, },
1061         {},
1062 };
1063 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1064
1065 MODULE_ALIAS("acpi");