Version:  2.0.40 2.2.26 2.4.37 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 4.5 4.6 4.7

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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 29 
 30 #include <linux/kernel.h>
 31 #include <linux/module.h>
 32 #include <linux/init.h>
 33 #include <linux/smp.h>
 34 #include <linux/sched.h>
 35 #include <linux/cpufreq.h>
 36 #include <linux/compiler.h>
 37 #include <linux/dmi.h>
 38 #include <linux/slab.h>
 39 
 40 #include <linux/acpi.h>
 41 #include <linux/io.h>
 42 #include <linux/delay.h>
 43 #include <linux/uaccess.h>
 44 
 45 #include <acpi/processor.h>
 46 
 47 #include <asm/msr.h>
 48 #include <asm/processor.h>
 49 #include <asm/cpufeature.h>
 50 
 51 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
 52 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
 53 MODULE_LICENSE("GPL");
 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         unsigned int resume;
 69         unsigned int cpu_feature;
 70         unsigned int acpi_perf_cpu;
 71         cpumask_var_t freqdomain_cpus;
 72         void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
 73         u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
 74 };
 75 
 76 /* acpi_perf_data is a pointer to percpu data. */
 77 static struct acpi_processor_performance __percpu *acpi_perf_data;
 78 
 79 static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
 80 {
 81         return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
 82 }
 83 
 84 static struct cpufreq_driver acpi_cpufreq_driver;
 85 
 86 static unsigned int acpi_pstate_strict;
 87 static struct msr __percpu *msrs;
 88 
 89 static bool boost_state(unsigned int cpu)
 90 {
 91         u32 lo, hi;
 92         u64 msr;
 93 
 94         switch (boot_cpu_data.x86_vendor) {
 95         case X86_VENDOR_INTEL:
 96                 rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
 97                 msr = lo | ((u64)hi << 32);
 98                 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
 99         case X86_VENDOR_AMD:
100                 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
101                 msr = lo | ((u64)hi << 32);
102                 return !(msr & MSR_K7_HWCR_CPB_DIS);
103         }
104         return false;
105 }
106 
107 static void boost_set_msrs(bool enable, const struct cpumask *cpumask)
108 {
109         u32 cpu;
110         u32 msr_addr;
111         u64 msr_mask;
112 
113         switch (boot_cpu_data.x86_vendor) {
114         case X86_VENDOR_INTEL:
115                 msr_addr = MSR_IA32_MISC_ENABLE;
116                 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
117                 break;
118         case X86_VENDOR_AMD:
119                 msr_addr = MSR_K7_HWCR;
120                 msr_mask = MSR_K7_HWCR_CPB_DIS;
121                 break;
122         default:
123                 return;
124         }
125 
126         rdmsr_on_cpus(cpumask, msr_addr, msrs);
127 
128         for_each_cpu(cpu, cpumask) {
129                 struct msr *reg = per_cpu_ptr(msrs, cpu);
130                 if (enable)
131                         reg->q &= ~msr_mask;
132                 else
133                         reg->q |= msr_mask;
134         }
135 
136         wrmsr_on_cpus(cpumask, msr_addr, msrs);
137 }
138 
139 static int set_boost(int val)
140 {
141         get_online_cpus();
142         boost_set_msrs(val, cpu_online_mask);
143         put_online_cpus();
144         pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
145 
146         return 0;
147 }
148 
149 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
150 {
151         struct acpi_cpufreq_data *data = policy->driver_data;
152 
153         if (unlikely(!data))
154                 return -ENODEV;
155 
156         return cpufreq_show_cpus(data->freqdomain_cpus, buf);
157 }
158 
159 cpufreq_freq_attr_ro(freqdomain_cpus);
160 
161 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
162 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
163                          size_t count)
164 {
165         int ret;
166         unsigned int val = 0;
167 
168         if (!acpi_cpufreq_driver.set_boost)
169                 return -EINVAL;
170 
171         ret = kstrtouint(buf, 10, &val);
172         if (ret || val > 1)
173                 return -EINVAL;
174 
175         set_boost(val);
176 
177         return count;
178 }
179 
180 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
181 {
182         return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
183 }
184 
185 cpufreq_freq_attr_rw(cpb);
186 #endif
187 
188 static int check_est_cpu(unsigned int cpuid)
189 {
190         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
191 
192         return cpu_has(cpu, X86_FEATURE_EST);
193 }
194 
195 static int check_amd_hwpstate_cpu(unsigned int cpuid)
196 {
197         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
198 
199         return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
200 }
201 
202 static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
203 {
204         struct acpi_cpufreq_data *data = policy->driver_data;
205         struct acpi_processor_performance *perf;
206         int i;
207 
208         perf = to_perf_data(data);
209 
210         for (i = 0; i < perf->state_count; i++) {
211                 if (value == perf->states[i].status)
212                         return policy->freq_table[i].frequency;
213         }
214         return 0;
215 }
216 
217 static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
218 {
219         struct acpi_cpufreq_data *data = policy->driver_data;
220         struct cpufreq_frequency_table *pos;
221         struct acpi_processor_performance *perf;
222 
223         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
224                 msr &= AMD_MSR_RANGE;
225         else
226                 msr &= INTEL_MSR_RANGE;
227 
228         perf = to_perf_data(data);
229 
230         cpufreq_for_each_entry(pos, policy->freq_table)
231                 if (msr == perf->states[pos->driver_data].status)
232                         return pos->frequency;
233         return policy->freq_table[0].frequency;
234 }
235 
236 static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
237 {
238         struct acpi_cpufreq_data *data = policy->driver_data;
239 
240         switch (data->cpu_feature) {
241         case SYSTEM_INTEL_MSR_CAPABLE:
242         case SYSTEM_AMD_MSR_CAPABLE:
243                 return extract_msr(policy, val);
244         case SYSTEM_IO_CAPABLE:
245                 return extract_io(policy, val);
246         default:
247                 return 0;
248         }
249 }
250 
251 static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
252 {
253         u32 val, dummy;
254 
255         rdmsr(MSR_IA32_PERF_CTL, val, dummy);
256         return val;
257 }
258 
259 static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
260 {
261         u32 lo, hi;
262 
263         rdmsr(MSR_IA32_PERF_CTL, lo, hi);
264         lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
265         wrmsr(MSR_IA32_PERF_CTL, lo, hi);
266 }
267 
268 static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
269 {
270         u32 val, dummy;
271 
272         rdmsr(MSR_AMD_PERF_CTL, val, dummy);
273         return val;
274 }
275 
276 static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
277 {
278         wrmsr(MSR_AMD_PERF_CTL, val, 0);
279 }
280 
281 static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
282 {
283         u32 val;
284 
285         acpi_os_read_port(reg->address, &val, reg->bit_width);
286         return val;
287 }
288 
289 static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
290 {
291         acpi_os_write_port(reg->address, val, reg->bit_width);
292 }
293 
294 struct drv_cmd {
295         struct acpi_pct_register *reg;
296         u32 val;
297         union {
298                 void (*write)(struct acpi_pct_register *reg, u32 val);
299                 u32 (*read)(struct acpi_pct_register *reg);
300         } func;
301 };
302 
303 /* Called via smp_call_function_single(), on the target CPU */
304 static void do_drv_read(void *_cmd)
305 {
306         struct drv_cmd *cmd = _cmd;
307 
308         cmd->val = cmd->func.read(cmd->reg);
309 }
310 
311 static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
312 {
313         struct acpi_processor_performance *perf = to_perf_data(data);
314         struct drv_cmd cmd = {
315                 .reg = &perf->control_register,
316                 .func.read = data->cpu_freq_read,
317         };
318         int err;
319 
320         err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
321         WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
322         return cmd.val;
323 }
324 
325 /* Called via smp_call_function_many(), on the target CPUs */
326 static void do_drv_write(void *_cmd)
327 {
328         struct drv_cmd *cmd = _cmd;
329 
330         cmd->func.write(cmd->reg, cmd->val);
331 }
332 
333 static void drv_write(struct acpi_cpufreq_data *data,
334                       const struct cpumask *mask, u32 val)
335 {
336         struct acpi_processor_performance *perf = to_perf_data(data);
337         struct drv_cmd cmd = {
338                 .reg = &perf->control_register,
339                 .val = val,
340                 .func.write = data->cpu_freq_write,
341         };
342         int this_cpu;
343 
344         this_cpu = get_cpu();
345         if (cpumask_test_cpu(this_cpu, mask))
346                 do_drv_write(&cmd);
347 
348         smp_call_function_many(mask, do_drv_write, &cmd, 1);
349         put_cpu();
350 }
351 
352 static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
353 {
354         u32 val;
355 
356         if (unlikely(cpumask_empty(mask)))
357                 return 0;
358 
359         val = drv_read(data, mask);
360 
361         pr_debug("get_cur_val = %u\n", val);
362 
363         return val;
364 }
365 
366 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
367 {
368         struct acpi_cpufreq_data *data;
369         struct cpufreq_policy *policy;
370         unsigned int freq;
371         unsigned int cached_freq;
372 
373         pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
374 
375         policy = cpufreq_cpu_get_raw(cpu);
376         if (unlikely(!policy))
377                 return 0;
378 
379         data = policy->driver_data;
380         if (unlikely(!data || !policy->freq_table))
381                 return 0;
382 
383         cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
384         freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
385         if (freq != cached_freq) {
386                 /*
387                  * The dreaded BIOS frequency change behind our back.
388                  * Force set the frequency on next target call.
389                  */
390                 data->resume = 1;
391         }
392 
393         pr_debug("cur freq = %u\n", freq);
394 
395         return freq;
396 }
397 
398 static unsigned int check_freqs(struct cpufreq_policy *policy,
399                                 const struct cpumask *mask, unsigned int freq)
400 {
401         struct acpi_cpufreq_data *data = policy->driver_data;
402         unsigned int cur_freq;
403         unsigned int i;
404 
405         for (i = 0; i < 100; i++) {
406                 cur_freq = extract_freq(policy, get_cur_val(mask, data));
407                 if (cur_freq == freq)
408                         return 1;
409                 udelay(10);
410         }
411         return 0;
412 }
413 
414 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
415                                unsigned int index)
416 {
417         struct acpi_cpufreq_data *data = policy->driver_data;
418         struct acpi_processor_performance *perf;
419         const struct cpumask *mask;
420         unsigned int next_perf_state = 0; /* Index into perf table */
421         int result = 0;
422 
423         if (unlikely(!data)) {
424                 return -ENODEV;
425         }
426 
427         perf = to_perf_data(data);
428         next_perf_state = policy->freq_table[index].driver_data;
429         if (perf->state == next_perf_state) {
430                 if (unlikely(data->resume)) {
431                         pr_debug("Called after resume, resetting to P%d\n",
432                                 next_perf_state);
433                         data->resume = 0;
434                 } else {
435                         pr_debug("Already at target state (P%d)\n",
436                                 next_perf_state);
437                         return 0;
438                 }
439         }
440 
441         /*
442          * The core won't allow CPUs to go away until the governor has been
443          * stopped, so we can rely on the stability of policy->cpus.
444          */
445         mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
446                 cpumask_of(policy->cpu) : policy->cpus;
447 
448         drv_write(data, mask, perf->states[next_perf_state].control);
449 
450         if (acpi_pstate_strict) {
451                 if (!check_freqs(policy, mask,
452                                  policy->freq_table[index].frequency)) {
453                         pr_debug("acpi_cpufreq_target failed (%d)\n",
454                                 policy->cpu);
455                         result = -EAGAIN;
456                 }
457         }
458 
459         if (!result)
460                 perf->state = next_perf_state;
461 
462         return result;
463 }
464 
465 unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
466                                       unsigned int target_freq)
467 {
468         struct acpi_cpufreq_data *data = policy->driver_data;
469         struct acpi_processor_performance *perf;
470         struct cpufreq_frequency_table *entry;
471         unsigned int next_perf_state, next_freq, freq;
472 
473         /*
474          * Find the closest frequency above target_freq.
475          *
476          * The table is sorted in the reverse order with respect to the
477          * frequency and all of the entries are valid (see the initialization).
478          */
479         entry = policy->freq_table;
480         do {
481                 entry++;
482                 freq = entry->frequency;
483         } while (freq >= target_freq && freq != CPUFREQ_TABLE_END);
484         entry--;
485         next_freq = entry->frequency;
486         next_perf_state = entry->driver_data;
487 
488         perf = to_perf_data(data);
489         if (perf->state == next_perf_state) {
490                 if (unlikely(data->resume))
491                         data->resume = 0;
492                 else
493                         return next_freq;
494         }
495 
496         data->cpu_freq_write(&perf->control_register,
497                              perf->states[next_perf_state].control);
498         perf->state = next_perf_state;
499         return next_freq;
500 }
501 
502 static unsigned long
503 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
504 {
505         struct acpi_processor_performance *perf;
506 
507         perf = to_perf_data(data);
508         if (cpu_khz) {
509                 /* search the closest match to cpu_khz */
510                 unsigned int i;
511                 unsigned long freq;
512                 unsigned long freqn = perf->states[0].core_frequency * 1000;
513 
514                 for (i = 0; i < (perf->state_count-1); i++) {
515                         freq = freqn;
516                         freqn = perf->states[i+1].core_frequency * 1000;
517                         if ((2 * cpu_khz) > (freqn + freq)) {
518                                 perf->state = i;
519                                 return freq;
520                         }
521                 }
522                 perf->state = perf->state_count-1;
523                 return freqn;
524         } else {
525                 /* assume CPU is at P0... */
526                 perf->state = 0;
527                 return perf->states[0].core_frequency * 1000;
528         }
529 }
530 
531 static void free_acpi_perf_data(void)
532 {
533         unsigned int i;
534 
535         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
536         for_each_possible_cpu(i)
537                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
538                                  ->shared_cpu_map);
539         free_percpu(acpi_perf_data);
540 }
541 
542 static int boost_notify(struct notifier_block *nb, unsigned long action,
543                       void *hcpu)
544 {
545         unsigned cpu = (long)hcpu;
546         const struct cpumask *cpumask;
547 
548         cpumask = get_cpu_mask(cpu);
549 
550         /*
551          * Clear the boost-disable bit on the CPU_DOWN path so that
552          * this cpu cannot block the remaining ones from boosting. On
553          * the CPU_UP path we simply keep the boost-disable flag in
554          * sync with the current global state.
555          */
556 
557         switch (action) {
558         case CPU_DOWN_FAILED:
559         case CPU_DOWN_FAILED_FROZEN:
560         case CPU_ONLINE:
561         case CPU_ONLINE_FROZEN:
562                 boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
563                 break;
564 
565         case CPU_DOWN_PREPARE:
566         case CPU_DOWN_PREPARE_FROZEN:
567                 boost_set_msrs(1, cpumask);
568                 break;
569 
570         default:
571                 break;
572         }
573 
574         return NOTIFY_OK;
575 }
576 
577 
578 static struct notifier_block boost_nb = {
579         .notifier_call          = boost_notify,
580 };
581 
582 /*
583  * acpi_cpufreq_early_init - initialize ACPI P-States library
584  *
585  * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
586  * in order to determine correct frequency and voltage pairings. We can
587  * do _PDC and _PSD and find out the processor dependency for the
588  * actual init that will happen later...
589  */
590 static int __init acpi_cpufreq_early_init(void)
591 {
592         unsigned int i;
593         pr_debug("acpi_cpufreq_early_init\n");
594 
595         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
596         if (!acpi_perf_data) {
597                 pr_debug("Memory allocation error for acpi_perf_data.\n");
598                 return -ENOMEM;
599         }
600         for_each_possible_cpu(i) {
601                 if (!zalloc_cpumask_var_node(
602                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
603                         GFP_KERNEL, cpu_to_node(i))) {
604 
605                         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
606                         free_acpi_perf_data();
607                         return -ENOMEM;
608                 }
609         }
610 
611         /* Do initialization in ACPI core */
612         acpi_processor_preregister_performance(acpi_perf_data);
613         return 0;
614 }
615 
616 #ifdef CONFIG_SMP
617 /*
618  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
619  * or do it in BIOS firmware and won't inform about it to OS. If not
620  * detected, this has a side effect of making CPU run at a different speed
621  * than OS intended it to run at. Detect it and handle it cleanly.
622  */
623 static int bios_with_sw_any_bug;
624 
625 static int sw_any_bug_found(const struct dmi_system_id *d)
626 {
627         bios_with_sw_any_bug = 1;
628         return 0;
629 }
630 
631 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
632         {
633                 .callback = sw_any_bug_found,
634                 .ident = "Supermicro Server X6DLP",
635                 .matches = {
636                         DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
637                         DMI_MATCH(DMI_BIOS_VERSION, "080010"),
638                         DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
639                 },
640         },
641         { }
642 };
643 
644 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
645 {
646         /* Intel Xeon Processor 7100 Series Specification Update
647          * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
648          * AL30: A Machine Check Exception (MCE) Occurring during an
649          * Enhanced Intel SpeedStep Technology Ratio Change May Cause
650          * Both Processor Cores to Lock Up. */
651         if (c->x86_vendor == X86_VENDOR_INTEL) {
652                 if ((c->x86 == 15) &&
653                     (c->x86_model == 6) &&
654                     (c->x86_mask == 8)) {
655                         pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
656                         return -ENODEV;
657                     }
658                 }
659         return 0;
660 }
661 #endif
662 
663 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
664 {
665         unsigned int i;
666         unsigned int valid_states = 0;
667         unsigned int cpu = policy->cpu;
668         struct acpi_cpufreq_data *data;
669         unsigned int result = 0;
670         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
671         struct acpi_processor_performance *perf;
672         struct cpufreq_frequency_table *freq_table;
673 #ifdef CONFIG_SMP
674         static int blacklisted;
675 #endif
676 
677         pr_debug("acpi_cpufreq_cpu_init\n");
678 
679 #ifdef CONFIG_SMP
680         if (blacklisted)
681                 return blacklisted;
682         blacklisted = acpi_cpufreq_blacklist(c);
683         if (blacklisted)
684                 return blacklisted;
685 #endif
686 
687         data = kzalloc(sizeof(*data), GFP_KERNEL);
688         if (!data)
689                 return -ENOMEM;
690 
691         if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
692                 result = -ENOMEM;
693                 goto err_free;
694         }
695 
696         perf = per_cpu_ptr(acpi_perf_data, cpu);
697         data->acpi_perf_cpu = cpu;
698         policy->driver_data = data;
699 
700         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
701                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
702 
703         result = acpi_processor_register_performance(perf, cpu);
704         if (result)
705                 goto err_free_mask;
706 
707         policy->shared_type = perf->shared_type;
708 
709         /*
710          * Will let policy->cpus know about dependency only when software
711          * coordination is required.
712          */
713         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
714             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
715                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
716         }
717         cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
718 
719 #ifdef CONFIG_SMP
720         dmi_check_system(sw_any_bug_dmi_table);
721         if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
722                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
723                 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
724         }
725 
726         if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
727                 cpumask_clear(policy->cpus);
728                 cpumask_set_cpu(cpu, policy->cpus);
729                 cpumask_copy(data->freqdomain_cpus,
730                              topology_sibling_cpumask(cpu));
731                 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
732                 pr_info_once("overriding BIOS provided _PSD data\n");
733         }
734 #endif
735 
736         /* capability check */
737         if (perf->state_count <= 1) {
738                 pr_debug("No P-States\n");
739                 result = -ENODEV;
740                 goto err_unreg;
741         }
742 
743         if (perf->control_register.space_id != perf->status_register.space_id) {
744                 result = -ENODEV;
745                 goto err_unreg;
746         }
747 
748         switch (perf->control_register.space_id) {
749         case ACPI_ADR_SPACE_SYSTEM_IO:
750                 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
751                     boot_cpu_data.x86 == 0xf) {
752                         pr_debug("AMD K8 systems must use native drivers.\n");
753                         result = -ENODEV;
754                         goto err_unreg;
755                 }
756                 pr_debug("SYSTEM IO addr space\n");
757                 data->cpu_feature = SYSTEM_IO_CAPABLE;
758                 data->cpu_freq_read = cpu_freq_read_io;
759                 data->cpu_freq_write = cpu_freq_write_io;
760                 break;
761         case ACPI_ADR_SPACE_FIXED_HARDWARE:
762                 pr_debug("HARDWARE addr space\n");
763                 if (check_est_cpu(cpu)) {
764                         data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
765                         data->cpu_freq_read = cpu_freq_read_intel;
766                         data->cpu_freq_write = cpu_freq_write_intel;
767                         break;
768                 }
769                 if (check_amd_hwpstate_cpu(cpu)) {
770                         data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
771                         data->cpu_freq_read = cpu_freq_read_amd;
772                         data->cpu_freq_write = cpu_freq_write_amd;
773                         break;
774                 }
775                 result = -ENODEV;
776                 goto err_unreg;
777         default:
778                 pr_debug("Unknown addr space %d\n",
779                         (u32) (perf->control_register.space_id));
780                 result = -ENODEV;
781                 goto err_unreg;
782         }
783 
784         freq_table = kzalloc(sizeof(*freq_table) *
785                     (perf->state_count+1), GFP_KERNEL);
786         if (!freq_table) {
787                 result = -ENOMEM;
788                 goto err_unreg;
789         }
790 
791         /* detect transition latency */
792         policy->cpuinfo.transition_latency = 0;
793         for (i = 0; i < perf->state_count; i++) {
794                 if ((perf->states[i].transition_latency * 1000) >
795                     policy->cpuinfo.transition_latency)
796                         policy->cpuinfo.transition_latency =
797                             perf->states[i].transition_latency * 1000;
798         }
799 
800         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
801         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
802             policy->cpuinfo.transition_latency > 20 * 1000) {
803                 policy->cpuinfo.transition_latency = 20 * 1000;
804                 pr_info_once("P-state transition latency capped at 20 uS\n");
805         }
806 
807         /* table init */
808         for (i = 0; i < perf->state_count; i++) {
809                 if (i > 0 && perf->states[i].core_frequency >=
810                     freq_table[valid_states-1].frequency / 1000)
811                         continue;
812 
813                 freq_table[valid_states].driver_data = i;
814                 freq_table[valid_states].frequency =
815                     perf->states[i].core_frequency * 1000;
816                 valid_states++;
817         }
818         freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
819         perf->state = 0;
820 
821         result = cpufreq_table_validate_and_show(policy, freq_table);
822         if (result)
823                 goto err_freqfree;
824 
825         if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
826                 pr_warn(FW_WARN "P-state 0 is not max freq\n");
827 
828         switch (perf->control_register.space_id) {
829         case ACPI_ADR_SPACE_SYSTEM_IO:
830                 /*
831                  * The core will not set policy->cur, because
832                  * cpufreq_driver->get is NULL, so we need to set it here.
833                  * However, we have to guess it, because the current speed is
834                  * unknown and not detectable via IO ports.
835                  */
836                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
837                 break;
838         case ACPI_ADR_SPACE_FIXED_HARDWARE:
839                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
840                 break;
841         default:
842                 break;
843         }
844 
845         /* notify BIOS that we exist */
846         acpi_processor_notify_smm(THIS_MODULE);
847 
848         pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
849         for (i = 0; i < perf->state_count; i++)
850                 pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
851                         (i == perf->state ? '*' : ' '), i,
852                         (u32) perf->states[i].core_frequency,
853                         (u32) perf->states[i].power,
854                         (u32) perf->states[i].transition_latency);
855 
856         /*
857          * the first call to ->target() should result in us actually
858          * writing something to the appropriate registers.
859          */
860         data->resume = 1;
861 
862         policy->fast_switch_possible = !acpi_pstate_strict &&
863                 !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
864 
865         return result;
866 
867 err_freqfree:
868         kfree(freq_table);
869 err_unreg:
870         acpi_processor_unregister_performance(cpu);
871 err_free_mask:
872         free_cpumask_var(data->freqdomain_cpus);
873 err_free:
874         kfree(data);
875         policy->driver_data = NULL;
876 
877         return result;
878 }
879 
880 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
881 {
882         struct acpi_cpufreq_data *data = policy->driver_data;
883 
884         pr_debug("acpi_cpufreq_cpu_exit\n");
885 
886         policy->fast_switch_possible = false;
887         policy->driver_data = NULL;
888         acpi_processor_unregister_performance(data->acpi_perf_cpu);
889         free_cpumask_var(data->freqdomain_cpus);
890         kfree(policy->freq_table);
891         kfree(data);
892 
893         return 0;
894 }
895 
896 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
897 {
898         struct acpi_cpufreq_data *data = policy->driver_data;
899 
900         pr_debug("acpi_cpufreq_resume\n");
901 
902         data->resume = 1;
903 
904         return 0;
905 }
906 
907 static struct freq_attr *acpi_cpufreq_attr[] = {
908         &cpufreq_freq_attr_scaling_available_freqs,
909         &freqdomain_cpus,
910 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
911         &cpb,
912 #endif
913         NULL,
914 };
915 
916 static struct cpufreq_driver acpi_cpufreq_driver = {
917         .verify         = cpufreq_generic_frequency_table_verify,
918         .target_index   = acpi_cpufreq_target,
919         .fast_switch    = acpi_cpufreq_fast_switch,
920         .bios_limit     = acpi_processor_get_bios_limit,
921         .init           = acpi_cpufreq_cpu_init,
922         .exit           = acpi_cpufreq_cpu_exit,
923         .resume         = acpi_cpufreq_resume,
924         .name           = "acpi-cpufreq",
925         .attr           = acpi_cpufreq_attr,
926 };
927 
928 static void __init acpi_cpufreq_boost_init(void)
929 {
930         if (boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)) {
931                 msrs = msrs_alloc();
932 
933                 if (!msrs)
934                         return;
935 
936                 acpi_cpufreq_driver.set_boost = set_boost;
937                 acpi_cpufreq_driver.boost_enabled = boost_state(0);
938 
939                 cpu_notifier_register_begin();
940 
941                 /* Force all MSRs to the same value */
942                 boost_set_msrs(acpi_cpufreq_driver.boost_enabled,
943                                cpu_online_mask);
944 
945                 __register_cpu_notifier(&boost_nb);
946 
947                 cpu_notifier_register_done();
948         }
949 }
950 
951 static void acpi_cpufreq_boost_exit(void)
952 {
953         if (msrs) {
954                 unregister_cpu_notifier(&boost_nb);
955 
956                 msrs_free(msrs);
957                 msrs = NULL;
958         }
959 }
960 
961 static int __init acpi_cpufreq_init(void)
962 {
963         int ret;
964 
965         if (acpi_disabled)
966                 return -ENODEV;
967 
968         /* don't keep reloading if cpufreq_driver exists */
969         if (cpufreq_get_current_driver())
970                 return -EEXIST;
971 
972         pr_debug("acpi_cpufreq_init\n");
973 
974         ret = acpi_cpufreq_early_init();
975         if (ret)
976                 return ret;
977 
978 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
979         /* this is a sysfs file with a strange name and an even stranger
980          * semantic - per CPU instantiation, but system global effect.
981          * Lets enable it only on AMD CPUs for compatibility reasons and
982          * only if configured. This is considered legacy code, which
983          * will probably be removed at some point in the future.
984          */
985         if (!check_amd_hwpstate_cpu(0)) {
986                 struct freq_attr **attr;
987 
988                 pr_debug("CPB unsupported, do not expose it\n");
989 
990                 for (attr = acpi_cpufreq_attr; *attr; attr++)
991                         if (*attr == &cpb) {
992                                 *attr = NULL;
993                                 break;
994                         }
995         }
996 #endif
997         acpi_cpufreq_boost_init();
998 
999         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
1000         if (ret) {
1001                 free_acpi_perf_data();
1002                 acpi_cpufreq_boost_exit();
1003         }
1004         return ret;
1005 }
1006 
1007 static void __exit acpi_cpufreq_exit(void)
1008 {
1009         pr_debug("acpi_cpufreq_exit\n");
1010 
1011         acpi_cpufreq_boost_exit();
1012 
1013         cpufreq_unregister_driver(&acpi_cpufreq_driver);
1014 
1015         free_acpi_perf_data();
1016 }
1017 
1018 module_param(acpi_pstate_strict, uint, 0644);
1019 MODULE_PARM_DESC(acpi_pstate_strict,
1020         "value 0 or non-zero. non-zero -> strict ACPI checks are "
1021         "performed during frequency changes.");
1022 
1023 late_initcall(acpi_cpufreq_init);
1024 module_exit(acpi_cpufreq_exit);
1025 
1026 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
1027         X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1028         X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1029         {}
1030 };
1031 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1032 
1033 static const struct acpi_device_id processor_device_ids[] = {
1034         {ACPI_PROCESSOR_OBJECT_HID, },
1035         {ACPI_PROCESSOR_DEVICE_HID, },
1036         {},
1037 };
1038 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1039 
1040 MODULE_ALIAS("acpi");
1041 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us