Version:  2.0.40 2.2.26 2.4.37 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4

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

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