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 4.5

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

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