Version:  2.0.40 2.2.26 2.4.37 2.6.39 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15

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

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