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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 
 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 int boost_set_msr(bool enable)
107 {
108         u32 msr_addr;
109         u64 msr_mask, val;
110 
111         switch (boot_cpu_data.x86_vendor) {
112         case X86_VENDOR_INTEL:
113                 msr_addr = MSR_IA32_MISC_ENABLE;
114                 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
115                 break;
116         case X86_VENDOR_AMD:
117                 msr_addr = MSR_K7_HWCR;
118                 msr_mask = MSR_K7_HWCR_CPB_DIS;
119                 break;
120         default:
121                 return -EINVAL;
122         }
123 
124         rdmsrl(msr_addr, val);
125 
126         if (enable)
127                 val &= ~msr_mask;
128         else
129                 val |= msr_mask;
130 
131         wrmsrl(msr_addr, val);
132         return 0;
133 }
134 
135 static void boost_set_msr_each(void *p_en)
136 {
137         bool enable = (bool) p_en;
138 
139         boost_set_msr(enable);
140 }
141 
142 static int set_boost(int val)
143 {
144         get_online_cpus();
145         on_each_cpu(boost_set_msr_each, (void *)(long)val, 1);
146         put_online_cpus();
147         pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
148 
149         return 0;
150 }
151 
152 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
153 {
154         struct acpi_cpufreq_data *data = policy->driver_data;
155 
156         if (unlikely(!data))
157                 return -ENODEV;
158 
159         return cpufreq_show_cpus(data->freqdomain_cpus, buf);
160 }
161 
162 cpufreq_freq_attr_ro(freqdomain_cpus);
163 
164 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
165 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
166                          size_t count)
167 {
168         int ret;
169         unsigned int val = 0;
170 
171         if (!acpi_cpufreq_driver.set_boost)
172                 return -EINVAL;
173 
174         ret = kstrtouint(buf, 10, &val);
175         if (ret || val > 1)
176                 return -EINVAL;
177 
178         set_boost(val);
179 
180         return count;
181 }
182 
183 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
184 {
185         return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
186 }
187 
188 cpufreq_freq_attr_rw(cpb);
189 #endif
190 
191 static int check_est_cpu(unsigned int cpuid)
192 {
193         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
194 
195         return cpu_has(cpu, X86_FEATURE_EST);
196 }
197 
198 static int check_amd_hwpstate_cpu(unsigned int cpuid)
199 {
200         struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
201 
202         return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
203 }
204 
205 static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
206 {
207         struct acpi_cpufreq_data *data = policy->driver_data;
208         struct acpi_processor_performance *perf;
209         int i;
210 
211         perf = to_perf_data(data);
212 
213         for (i = 0; i < perf->state_count; i++) {
214                 if (value == perf->states[i].status)
215                         return policy->freq_table[i].frequency;
216         }
217         return 0;
218 }
219 
220 static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
221 {
222         struct acpi_cpufreq_data *data = policy->driver_data;
223         struct cpufreq_frequency_table *pos;
224         struct acpi_processor_performance *perf;
225 
226         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
227                 msr &= AMD_MSR_RANGE;
228         else
229                 msr &= INTEL_MSR_RANGE;
230 
231         perf = to_perf_data(data);
232 
233         cpufreq_for_each_entry(pos, policy->freq_table)
234                 if (msr == perf->states[pos->driver_data].status)
235                         return pos->frequency;
236         return policy->freq_table[0].frequency;
237 }
238 
239 static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
240 {
241         struct acpi_cpufreq_data *data = policy->driver_data;
242 
243         switch (data->cpu_feature) {
244         case SYSTEM_INTEL_MSR_CAPABLE:
245         case SYSTEM_AMD_MSR_CAPABLE:
246                 return extract_msr(policy, val);
247         case SYSTEM_IO_CAPABLE:
248                 return extract_io(policy, val);
249         default:
250                 return 0;
251         }
252 }
253 
254 static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
255 {
256         u32 val, dummy;
257 
258         rdmsr(MSR_IA32_PERF_CTL, val, dummy);
259         return val;
260 }
261 
262 static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
263 {
264         u32 lo, hi;
265 
266         rdmsr(MSR_IA32_PERF_CTL, lo, hi);
267         lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
268         wrmsr(MSR_IA32_PERF_CTL, lo, hi);
269 }
270 
271 static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
272 {
273         u32 val, dummy;
274 
275         rdmsr(MSR_AMD_PERF_CTL, val, dummy);
276         return val;
277 }
278 
279 static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
280 {
281         wrmsr(MSR_AMD_PERF_CTL, val, 0);
282 }
283 
284 static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
285 {
286         u32 val;
287 
288         acpi_os_read_port(reg->address, &val, reg->bit_width);
289         return val;
290 }
291 
292 static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
293 {
294         acpi_os_write_port(reg->address, val, reg->bit_width);
295 }
296 
297 struct drv_cmd {
298         struct acpi_pct_register *reg;
299         u32 val;
300         union {
301                 void (*write)(struct acpi_pct_register *reg, u32 val);
302                 u32 (*read)(struct acpi_pct_register *reg);
303         } func;
304 };
305 
306 /* Called via smp_call_function_single(), on the target CPU */
307 static void do_drv_read(void *_cmd)
308 {
309         struct drv_cmd *cmd = _cmd;
310 
311         cmd->val = cmd->func.read(cmd->reg);
312 }
313 
314 static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
315 {
316         struct acpi_processor_performance *perf = to_perf_data(data);
317         struct drv_cmd cmd = {
318                 .reg = &perf->control_register,
319                 .func.read = data->cpu_freq_read,
320         };
321         int err;
322 
323         err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
324         WARN_ON_ONCE(err);      /* smp_call_function_any() was buggy? */
325         return cmd.val;
326 }
327 
328 /* Called via smp_call_function_many(), on the target CPUs */
329 static void do_drv_write(void *_cmd)
330 {
331         struct drv_cmd *cmd = _cmd;
332 
333         cmd->func.write(cmd->reg, cmd->val);
334 }
335 
336 static void drv_write(struct acpi_cpufreq_data *data,
337                       const struct cpumask *mask, u32 val)
338 {
339         struct acpi_processor_performance *perf = to_perf_data(data);
340         struct drv_cmd cmd = {
341                 .reg = &perf->control_register,
342                 .val = val,
343                 .func.write = data->cpu_freq_write,
344         };
345         int this_cpu;
346 
347         this_cpu = get_cpu();
348         if (cpumask_test_cpu(this_cpu, mask))
349                 do_drv_write(&cmd);
350 
351         smp_call_function_many(mask, do_drv_write, &cmd, 1);
352         put_cpu();
353 }
354 
355 static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
356 {
357         u32 val;
358 
359         if (unlikely(cpumask_empty(mask)))
360                 return 0;
361 
362         val = drv_read(data, mask);
363 
364         pr_debug("get_cur_val = %u\n", val);
365 
366         return val;
367 }
368 
369 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
370 {
371         struct acpi_cpufreq_data *data;
372         struct cpufreq_policy *policy;
373         unsigned int freq;
374         unsigned int cached_freq;
375 
376         pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
377 
378         policy = cpufreq_cpu_get_raw(cpu);
379         if (unlikely(!policy))
380                 return 0;
381 
382         data = policy->driver_data;
383         if (unlikely(!data || !policy->freq_table))
384                 return 0;
385 
386         cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
387         freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
388         if (freq != cached_freq) {
389                 /*
390                  * The dreaded BIOS frequency change behind our back.
391                  * Force set the frequency on next target call.
392                  */
393                 data->resume = 1;
394         }
395 
396         pr_debug("cur freq = %u\n", freq);
397 
398         return freq;
399 }
400 
401 static unsigned int check_freqs(struct cpufreq_policy *policy,
402                                 const struct cpumask *mask, unsigned int freq)
403 {
404         struct acpi_cpufreq_data *data = policy->driver_data;
405         unsigned int cur_freq;
406         unsigned int i;
407 
408         for (i = 0; i < 100; i++) {
409                 cur_freq = extract_freq(policy, get_cur_val(mask, data));
410                 if (cur_freq == freq)
411                         return 1;
412                 udelay(10);
413         }
414         return 0;
415 }
416 
417 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
418                                unsigned int index)
419 {
420         struct acpi_cpufreq_data *data = policy->driver_data;
421         struct acpi_processor_performance *perf;
422         const struct cpumask *mask;
423         unsigned int next_perf_state = 0; /* Index into perf table */
424         int result = 0;
425 
426         if (unlikely(!data)) {
427                 return -ENODEV;
428         }
429 
430         perf = to_perf_data(data);
431         next_perf_state = policy->freq_table[index].driver_data;
432         if (perf->state == next_perf_state) {
433                 if (unlikely(data->resume)) {
434                         pr_debug("Called after resume, resetting to P%d\n",
435                                 next_perf_state);
436                         data->resume = 0;
437                 } else {
438                         pr_debug("Already at target state (P%d)\n",
439                                 next_perf_state);
440                         return 0;
441                 }
442         }
443 
444         /*
445          * The core won't allow CPUs to go away until the governor has been
446          * stopped, so we can rely on the stability of policy->cpus.
447          */
448         mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
449                 cpumask_of(policy->cpu) : policy->cpus;
450 
451         drv_write(data, mask, perf->states[next_perf_state].control);
452 
453         if (acpi_pstate_strict) {
454                 if (!check_freqs(policy, mask,
455                                  policy->freq_table[index].frequency)) {
456                         pr_debug("acpi_cpufreq_target failed (%d)\n",
457                                 policy->cpu);
458                         result = -EAGAIN;
459                 }
460         }
461 
462         if (!result)
463                 perf->state = next_perf_state;
464 
465         return result;
466 }
467 
468 unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
469                                       unsigned int target_freq)
470 {
471         struct acpi_cpufreq_data *data = policy->driver_data;
472         struct acpi_processor_performance *perf;
473         struct cpufreq_frequency_table *entry;
474         unsigned int next_perf_state, next_freq, index;
475 
476         /*
477          * Find the closest frequency above target_freq.
478          */
479         if (policy->cached_target_freq == target_freq)
480                 index = policy->cached_resolved_idx;
481         else
482                 index = cpufreq_table_find_index_dl(policy, target_freq);
483 
484         entry = &policy->freq_table[index];
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 cpufreq_boost_online(unsigned int cpu)
543 {
544         /*
545          * On the CPU_UP path we simply keep the boost-disable flag
546          * in sync with the current global state.
547          */
548         return boost_set_msr(acpi_cpufreq_driver.boost_enabled);
549 }
550 
551 static int cpufreq_boost_down_prep(unsigned int cpu)
552 {
553         /*
554          * Clear the boost-disable bit on the CPU_DOWN path so that
555          * this cpu cannot block the remaining ones from boosting.
556          */
557         return boost_set_msr(1);
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                         pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
634                         return -ENODEV;
635                     }
636                 }
637         return 0;
638 }
639 #endif
640 
641 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
642 {
643         unsigned int i;
644         unsigned int valid_states = 0;
645         unsigned int cpu = policy->cpu;
646         struct acpi_cpufreq_data *data;
647         unsigned int result = 0;
648         struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
649         struct acpi_processor_performance *perf;
650         struct cpufreq_frequency_table *freq_table;
651 #ifdef CONFIG_SMP
652         static int blacklisted;
653 #endif
654 
655         pr_debug("acpi_cpufreq_cpu_init\n");
656 
657 #ifdef CONFIG_SMP
658         if (blacklisted)
659                 return blacklisted;
660         blacklisted = acpi_cpufreq_blacklist(c);
661         if (blacklisted)
662                 return blacklisted;
663 #endif
664 
665         data = kzalloc(sizeof(*data), GFP_KERNEL);
666         if (!data)
667                 return -ENOMEM;
668 
669         if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
670                 result = -ENOMEM;
671                 goto err_free;
672         }
673 
674         perf = per_cpu_ptr(acpi_perf_data, cpu);
675         data->acpi_perf_cpu = cpu;
676         policy->driver_data = data;
677 
678         if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
679                 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
680 
681         result = acpi_processor_register_performance(perf, cpu);
682         if (result)
683                 goto err_free_mask;
684 
685         policy->shared_type = perf->shared_type;
686 
687         /*
688          * Will let policy->cpus know about dependency only when software
689          * coordination is required.
690          */
691         if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
692             policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
693                 cpumask_copy(policy->cpus, perf->shared_cpu_map);
694         }
695         cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
696 
697 #ifdef CONFIG_SMP
698         dmi_check_system(sw_any_bug_dmi_table);
699         if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
700                 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
701                 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
702         }
703 
704         if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
705                 cpumask_clear(policy->cpus);
706                 cpumask_set_cpu(cpu, policy->cpus);
707                 cpumask_copy(data->freqdomain_cpus,
708                              topology_sibling_cpumask(cpu));
709                 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
710                 pr_info_once("overriding BIOS provided _PSD data\n");
711         }
712 #endif
713 
714         /* capability check */
715         if (perf->state_count <= 1) {
716                 pr_debug("No P-States\n");
717                 result = -ENODEV;
718                 goto err_unreg;
719         }
720 
721         if (perf->control_register.space_id != perf->status_register.space_id) {
722                 result = -ENODEV;
723                 goto err_unreg;
724         }
725 
726         switch (perf->control_register.space_id) {
727         case ACPI_ADR_SPACE_SYSTEM_IO:
728                 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
729                     boot_cpu_data.x86 == 0xf) {
730                         pr_debug("AMD K8 systems must use native drivers.\n");
731                         result = -ENODEV;
732                         goto err_unreg;
733                 }
734                 pr_debug("SYSTEM IO addr space\n");
735                 data->cpu_feature = SYSTEM_IO_CAPABLE;
736                 data->cpu_freq_read = cpu_freq_read_io;
737                 data->cpu_freq_write = cpu_freq_write_io;
738                 break;
739         case ACPI_ADR_SPACE_FIXED_HARDWARE:
740                 pr_debug("HARDWARE addr space\n");
741                 if (check_est_cpu(cpu)) {
742                         data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
743                         data->cpu_freq_read = cpu_freq_read_intel;
744                         data->cpu_freq_write = cpu_freq_write_intel;
745                         break;
746                 }
747                 if (check_amd_hwpstate_cpu(cpu)) {
748                         data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
749                         data->cpu_freq_read = cpu_freq_read_amd;
750                         data->cpu_freq_write = cpu_freq_write_amd;
751                         break;
752                 }
753                 result = -ENODEV;
754                 goto err_unreg;
755         default:
756                 pr_debug("Unknown addr space %d\n",
757                         (u32) (perf->control_register.space_id));
758                 result = -ENODEV;
759                 goto err_unreg;
760         }
761 
762         freq_table = kzalloc(sizeof(*freq_table) *
763                     (perf->state_count+1), GFP_KERNEL);
764         if (!freq_table) {
765                 result = -ENOMEM;
766                 goto err_unreg;
767         }
768 
769         /* detect transition latency */
770         policy->cpuinfo.transition_latency = 0;
771         for (i = 0; i < perf->state_count; i++) {
772                 if ((perf->states[i].transition_latency * 1000) >
773                     policy->cpuinfo.transition_latency)
774                         policy->cpuinfo.transition_latency =
775                             perf->states[i].transition_latency * 1000;
776         }
777 
778         /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
779         if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
780             policy->cpuinfo.transition_latency > 20 * 1000) {
781                 policy->cpuinfo.transition_latency = 20 * 1000;
782                 pr_info_once("P-state transition latency capped at 20 uS\n");
783         }
784 
785         /* table init */
786         for (i = 0; i < perf->state_count; i++) {
787                 if (i > 0 && perf->states[i].core_frequency >=
788                     freq_table[valid_states-1].frequency / 1000)
789                         continue;
790 
791                 freq_table[valid_states].driver_data = i;
792                 freq_table[valid_states].frequency =
793                     perf->states[i].core_frequency * 1000;
794                 valid_states++;
795         }
796         freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
797         perf->state = 0;
798 
799         result = cpufreq_table_validate_and_show(policy, freq_table);
800         if (result)
801                 goto err_freqfree;
802 
803         if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
804                 pr_warn(FW_WARN "P-state 0 is not max freq\n");
805 
806         switch (perf->control_register.space_id) {
807         case ACPI_ADR_SPACE_SYSTEM_IO:
808                 /*
809                  * The core will not set policy->cur, because
810                  * cpufreq_driver->get is NULL, so we need to set it here.
811                  * However, we have to guess it, because the current speed is
812                  * unknown and not detectable via IO ports.
813                  */
814                 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
815                 break;
816         case ACPI_ADR_SPACE_FIXED_HARDWARE:
817                 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
818                 break;
819         default:
820                 break;
821         }
822 
823         /* notify BIOS that we exist */
824         acpi_processor_notify_smm(THIS_MODULE);
825 
826         pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
827         for (i = 0; i < perf->state_count; i++)
828                 pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
829                         (i == perf->state ? '*' : ' '), i,
830                         (u32) perf->states[i].core_frequency,
831                         (u32) perf->states[i].power,
832                         (u32) perf->states[i].transition_latency);
833 
834         /*
835          * the first call to ->target() should result in us actually
836          * writing something to the appropriate registers.
837          */
838         data->resume = 1;
839 
840         policy->fast_switch_possible = !acpi_pstate_strict &&
841                 !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
842 
843         return result;
844 
845 err_freqfree:
846         kfree(freq_table);
847 err_unreg:
848         acpi_processor_unregister_performance(cpu);
849 err_free_mask:
850         free_cpumask_var(data->freqdomain_cpus);
851 err_free:
852         kfree(data);
853         policy->driver_data = NULL;
854 
855         return result;
856 }
857 
858 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
859 {
860         struct acpi_cpufreq_data *data = policy->driver_data;
861 
862         pr_debug("acpi_cpufreq_cpu_exit\n");
863 
864         policy->fast_switch_possible = false;
865         policy->driver_data = NULL;
866         acpi_processor_unregister_performance(data->acpi_perf_cpu);
867         free_cpumask_var(data->freqdomain_cpus);
868         kfree(policy->freq_table);
869         kfree(data);
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         .fast_switch    = acpi_cpufreq_fast_switch,
898         .bios_limit     = acpi_processor_get_bios_limit,
899         .init           = acpi_cpufreq_cpu_init,
900         .exit           = acpi_cpufreq_cpu_exit,
901         .resume         = acpi_cpufreq_resume,
902         .name           = "acpi-cpufreq",
903         .attr           = acpi_cpufreq_attr,
904 };
905 
906 static enum cpuhp_state acpi_cpufreq_online;
907 
908 static void __init acpi_cpufreq_boost_init(void)
909 {
910         int ret;
911 
912         if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)))
913                 return;
914 
915         acpi_cpufreq_driver.set_boost = set_boost;
916         acpi_cpufreq_driver.boost_enabled = boost_state(0);
917 
918         /*
919          * This calls the online callback on all online cpu and forces all
920          * MSRs to the same value.
921          */
922         ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online",
923                                 cpufreq_boost_online, cpufreq_boost_down_prep);
924         if (ret < 0) {
925                 pr_err("acpi_cpufreq: failed to register hotplug callbacks\n");
926                 return;
927         }
928         acpi_cpufreq_online = ret;
929 }
930 
931 static void acpi_cpufreq_boost_exit(void)
932 {
933         if (acpi_cpufreq_online > 0)
934                 cpuhp_remove_state_nocalls(acpi_cpufreq_online);
935 }
936 
937 static int __init acpi_cpufreq_init(void)
938 {
939         int ret;
940 
941         if (acpi_disabled)
942                 return -ENODEV;
943 
944         /* don't keep reloading if cpufreq_driver exists */
945         if (cpufreq_get_current_driver())
946                 return -EEXIST;
947 
948         pr_debug("acpi_cpufreq_init\n");
949 
950         ret = acpi_cpufreq_early_init();
951         if (ret)
952                 return ret;
953 
954 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
955         /* this is a sysfs file with a strange name and an even stranger
956          * semantic - per CPU instantiation, but system global effect.
957          * Lets enable it only on AMD CPUs for compatibility reasons and
958          * only if configured. This is considered legacy code, which
959          * will probably be removed at some point in the future.
960          */
961         if (!check_amd_hwpstate_cpu(0)) {
962                 struct freq_attr **attr;
963 
964                 pr_debug("CPB unsupported, do not expose it\n");
965 
966                 for (attr = acpi_cpufreq_attr; *attr; attr++)
967                         if (*attr == &cpb) {
968                                 *attr = NULL;
969                                 break;
970                         }
971         }
972 #endif
973         acpi_cpufreq_boost_init();
974 
975         ret = cpufreq_register_driver(&acpi_cpufreq_driver);
976         if (ret) {
977                 free_acpi_perf_data();
978                 acpi_cpufreq_boost_exit();
979         }
980         return ret;
981 }
982 
983 static void __exit acpi_cpufreq_exit(void)
984 {
985         pr_debug("acpi_cpufreq_exit\n");
986 
987         acpi_cpufreq_boost_exit();
988 
989         cpufreq_unregister_driver(&acpi_cpufreq_driver);
990 
991         free_acpi_perf_data();
992 }
993 
994 module_param(acpi_pstate_strict, uint, 0644);
995 MODULE_PARM_DESC(acpi_pstate_strict,
996         "value 0 or non-zero. non-zero -> strict ACPI checks are "
997         "performed during frequency changes.");
998 
999 late_initcall(acpi_cpufreq_init);
1000 module_exit(acpi_cpufreq_exit);
1001 
1002 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
1003         X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1004         X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1005         {}
1006 };
1007 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1008 
1009 static const struct acpi_device_id processor_device_ids[] = {
1010         {ACPI_PROCESSOR_OBJECT_HID, },
1011         {ACPI_PROCESSOR_DEVICE_HID, },
1012         {},
1013 };
1014 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1015 
1016 MODULE_ALIAS("acpi");
1017 

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