2 * acpi-cpufreq.c - ACPI Processor P-States Driver
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>
9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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.
25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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>
38 #include <linux/acpi.h>
40 #include <linux/delay.h>
41 #include <linux/uaccess.h>
43 #include <acpi/processor.h>
46 #include <asm/processor.h>
47 #include <asm/cpufeature.h>
49 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
50 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
51 MODULE_LICENSE("GPL");
53 #define PFX "acpi-cpufreq: "
56 UNDEFINED_CAPABLE = 0,
57 SYSTEM_INTEL_MSR_CAPABLE,
58 SYSTEM_AMD_MSR_CAPABLE,
62 #define INTEL_MSR_RANGE (0xffff)
63 #define AMD_MSR_RANGE (0x7)
65 #define MSR_K7_HWCR_CPB_DIS (1ULL << 25)
67 struct acpi_cpufreq_data {
68 struct cpufreq_frequency_table *freq_table;
70 unsigned int cpu_feature;
71 unsigned int acpi_perf_cpu;
72 cpumask_var_t freqdomain_cpus;
75 /* acpi_perf_data is a pointer to percpu data. */
76 static struct acpi_processor_performance __percpu *acpi_perf_data;
78 static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
80 return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
83 static struct cpufreq_driver acpi_cpufreq_driver;
85 static unsigned int acpi_pstate_strict;
86 static struct msr __percpu *msrs;
88 static bool boost_state(unsigned int cpu)
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);
99 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
100 msr = lo | ((u64)hi << 32);
101 return !(msr & MSR_K7_HWCR_CPB_DIS);
106 static void boost_set_msrs(bool enable, const struct cpumask *cpumask)
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;
118 msr_addr = MSR_K7_HWCR;
119 msr_mask = MSR_K7_HWCR_CPB_DIS;
125 rdmsr_on_cpus(cpumask, msr_addr, msrs);
127 for_each_cpu(cpu, cpumask) {
128 struct msr *reg = per_cpu_ptr(msrs, cpu);
135 wrmsr_on_cpus(cpumask, msr_addr, msrs);
138 static int _store_boost(int val)
141 boost_set_msrs(val, cpu_online_mask);
143 pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
148 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
150 struct acpi_cpufreq_data *data = policy->driver_data;
155 return cpufreq_show_cpus(data->freqdomain_cpus, buf);
158 cpufreq_freq_attr_ro(freqdomain_cpus);
160 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
161 static ssize_t store_boost(const char *buf, size_t count)
164 unsigned long val = 0;
166 if (!acpi_cpufreq_driver.boost_supported)
169 ret = kstrtoul(buf, 10, &val);
170 if (ret || (val > 1))
173 _store_boost((int) val);
178 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
181 return store_boost(buf, count);
184 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
186 return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
189 cpufreq_freq_attr_rw(cpb);
192 static int check_est_cpu(unsigned int cpuid)
194 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
196 return cpu_has(cpu, X86_FEATURE_EST);
199 static int check_amd_hwpstate_cpu(unsigned int cpuid)
201 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
203 return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
206 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
208 struct acpi_processor_performance *perf;
211 perf = to_perf_data(data);
213 for (i = 0; i < perf->state_count; i++) {
214 if (value == perf->states[i].status)
215 return data->freq_table[i].frequency;
220 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
222 struct cpufreq_frequency_table *pos;
223 struct acpi_processor_performance *perf;
225 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
226 msr &= AMD_MSR_RANGE;
228 msr &= INTEL_MSR_RANGE;
230 perf = to_perf_data(data);
232 cpufreq_for_each_entry(pos, data->freq_table)
233 if (msr == perf->states[pos->driver_data].status)
234 return pos->frequency;
235 return data->freq_table[0].frequency;
238 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
240 switch (data->cpu_feature) {
241 case SYSTEM_INTEL_MSR_CAPABLE:
242 case SYSTEM_AMD_MSR_CAPABLE:
243 return extract_msr(val, data);
244 case SYSTEM_IO_CAPABLE:
245 return extract_io(val, data);
262 const struct cpumask *mask;
270 /* Called via smp_call_function_single(), on the target CPU */
271 static void do_drv_read(void *_cmd)
273 struct drv_cmd *cmd = _cmd;
277 case SYSTEM_INTEL_MSR_CAPABLE:
278 case SYSTEM_AMD_MSR_CAPABLE:
279 rdmsr(cmd->addr.msr.reg, cmd->val, h);
281 case SYSTEM_IO_CAPABLE:
282 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
284 (u32)cmd->addr.io.bit_width);
291 /* Called via smp_call_function_many(), on the target CPUs */
292 static void do_drv_write(void *_cmd)
294 struct drv_cmd *cmd = _cmd;
298 case SYSTEM_INTEL_MSR_CAPABLE:
299 rdmsr(cmd->addr.msr.reg, lo, hi);
300 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
301 wrmsr(cmd->addr.msr.reg, lo, hi);
303 case SYSTEM_AMD_MSR_CAPABLE:
304 wrmsr(cmd->addr.msr.reg, cmd->val, 0);
306 case SYSTEM_IO_CAPABLE:
307 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
309 (u32)cmd->addr.io.bit_width);
316 static void drv_read(struct drv_cmd *cmd)
321 err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
322 WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */
325 static void drv_write(struct drv_cmd *cmd)
329 this_cpu = get_cpu();
330 if (cpumask_test_cpu(this_cpu, cmd->mask))
332 smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
337 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
339 struct acpi_processor_performance *perf;
342 if (unlikely(cpumask_empty(mask)))
345 switch (data->cpu_feature) {
346 case SYSTEM_INTEL_MSR_CAPABLE:
347 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
348 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
350 case SYSTEM_AMD_MSR_CAPABLE:
351 cmd.type = SYSTEM_AMD_MSR_CAPABLE;
352 cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
354 case SYSTEM_IO_CAPABLE:
355 cmd.type = SYSTEM_IO_CAPABLE;
356 perf = to_perf_data(data);
357 cmd.addr.io.port = perf->control_register.address;
358 cmd.addr.io.bit_width = perf->control_register.bit_width;
367 pr_debug("get_cur_val = %u\n", cmd.val);
372 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
374 struct acpi_cpufreq_data *data;
375 struct cpufreq_policy *policy;
377 unsigned int cached_freq;
379 pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
381 policy = cpufreq_cpu_get_raw(cpu);
382 if (unlikely(!policy))
385 data = policy->driver_data;
386 if (unlikely(!data || !data->freq_table))
389 cached_freq = data->freq_table[to_perf_data(data)->state].frequency;
390 freq = extract_freq(get_cur_val(cpumask_of(cpu), data), data);
391 if (freq != cached_freq) {
393 * The dreaded BIOS frequency change behind our back.
394 * Force set the frequency on next target call.
399 pr_debug("cur freq = %u\n", freq);
404 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
405 struct acpi_cpufreq_data *data)
407 unsigned int cur_freq;
410 for (i = 0; i < 100; i++) {
411 cur_freq = extract_freq(get_cur_val(mask, data), data);
412 if (cur_freq == freq)
419 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
422 struct acpi_cpufreq_data *data = policy->driver_data;
423 struct acpi_processor_performance *perf;
425 unsigned int next_perf_state = 0; /* Index into perf table */
428 if (unlikely(data == NULL || data->freq_table == NULL)) {
432 perf = to_perf_data(data);
433 next_perf_state = data->freq_table[index].driver_data;
434 if (perf->state == next_perf_state) {
435 if (unlikely(data->resume)) {
436 pr_debug("Called after resume, resetting to P%d\n",
440 pr_debug("Already at target state (P%d)\n",
446 switch (data->cpu_feature) {
447 case SYSTEM_INTEL_MSR_CAPABLE:
448 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
449 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
450 cmd.val = (u32) perf->states[next_perf_state].control;
452 case SYSTEM_AMD_MSR_CAPABLE:
453 cmd.type = SYSTEM_AMD_MSR_CAPABLE;
454 cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
455 cmd.val = (u32) perf->states[next_perf_state].control;
457 case SYSTEM_IO_CAPABLE:
458 cmd.type = SYSTEM_IO_CAPABLE;
459 cmd.addr.io.port = perf->control_register.address;
460 cmd.addr.io.bit_width = perf->control_register.bit_width;
461 cmd.val = (u32) perf->states[next_perf_state].control;
468 /* cpufreq holds the hotplug lock, so we are safe from here on */
469 if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
470 cmd.mask = policy->cpus;
472 cmd.mask = cpumask_of(policy->cpu);
476 if (acpi_pstate_strict) {
477 if (!check_freqs(cmd.mask, data->freq_table[index].frequency,
479 pr_debug("acpi_cpufreq_target failed (%d)\n",
486 perf->state = next_perf_state;
493 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
495 struct acpi_processor_performance *perf;
497 perf = to_perf_data(data);
499 /* search the closest match to cpu_khz */
502 unsigned long freqn = perf->states[0].core_frequency * 1000;
504 for (i = 0; i < (perf->state_count-1); i++) {
506 freqn = perf->states[i+1].core_frequency * 1000;
507 if ((2 * cpu_khz) > (freqn + freq)) {
512 perf->state = perf->state_count-1;
515 /* assume CPU is at P0... */
517 return perf->states[0].core_frequency * 1000;
521 static void free_acpi_perf_data(void)
525 /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
526 for_each_possible_cpu(i)
527 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
529 free_percpu(acpi_perf_data);
532 static int boost_notify(struct notifier_block *nb, unsigned long action,
535 unsigned cpu = (long)hcpu;
536 const struct cpumask *cpumask;
538 cpumask = get_cpu_mask(cpu);
541 * Clear the boost-disable bit on the CPU_DOWN path so that
542 * this cpu cannot block the remaining ones from boosting. On
543 * the CPU_UP path we simply keep the boost-disable flag in
544 * sync with the current global state.
549 case CPU_UP_PREPARE_FROZEN:
550 boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
553 case CPU_DOWN_PREPARE:
554 case CPU_DOWN_PREPARE_FROZEN:
555 boost_set_msrs(1, cpumask);
566 static struct notifier_block boost_nb = {
567 .notifier_call = boost_notify,
571 * acpi_cpufreq_early_init - initialize ACPI P-States library
573 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
574 * in order to determine correct frequency and voltage pairings. We can
575 * do _PDC and _PSD and find out the processor dependency for the
576 * actual init that will happen later...
578 static int __init acpi_cpufreq_early_init(void)
581 pr_debug("acpi_cpufreq_early_init\n");
583 acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
584 if (!acpi_perf_data) {
585 pr_debug("Memory allocation error for acpi_perf_data.\n");
588 for_each_possible_cpu(i) {
589 if (!zalloc_cpumask_var_node(
590 &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
591 GFP_KERNEL, cpu_to_node(i))) {
593 /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
594 free_acpi_perf_data();
599 /* Do initialization in ACPI core */
600 acpi_processor_preregister_performance(acpi_perf_data);
606 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
607 * or do it in BIOS firmware and won't inform about it to OS. If not
608 * detected, this has a side effect of making CPU run at a different speed
609 * than OS intended it to run at. Detect it and handle it cleanly.
611 static int bios_with_sw_any_bug;
613 static int sw_any_bug_found(const struct dmi_system_id *d)
615 bios_with_sw_any_bug = 1;
619 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
621 .callback = sw_any_bug_found,
622 .ident = "Supermicro Server X6DLP",
624 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
625 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
626 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
632 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
634 /* Intel Xeon Processor 7100 Series Specification Update
635 * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
636 * AL30: A Machine Check Exception (MCE) Occurring during an
637 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
638 * Both Processor Cores to Lock Up. */
639 if (c->x86_vendor == X86_VENDOR_INTEL) {
640 if ((c->x86 == 15) &&
641 (c->x86_model == 6) &&
642 (c->x86_mask == 8)) {
643 printk(KERN_INFO "acpi-cpufreq: Intel(R) "
644 "Xeon(R) 7100 Errata AL30, processors may "
645 "lock up on frequency changes: disabling "
654 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
657 unsigned int valid_states = 0;
658 unsigned int cpu = policy->cpu;
659 struct acpi_cpufreq_data *data;
660 unsigned int result = 0;
661 struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
662 struct acpi_processor_performance *perf;
664 static int blacklisted;
667 pr_debug("acpi_cpufreq_cpu_init\n");
672 blacklisted = acpi_cpufreq_blacklist(c);
677 data = kzalloc(sizeof(*data), GFP_KERNEL);
681 if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
686 perf = per_cpu_ptr(acpi_perf_data, cpu);
687 data->acpi_perf_cpu = cpu;
688 policy->driver_data = data;
690 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
691 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
693 result = acpi_processor_register_performance(perf, cpu);
697 policy->shared_type = perf->shared_type;
700 * Will let policy->cpus know about dependency only when software
701 * coordination is required.
703 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
704 policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
705 cpumask_copy(policy->cpus, perf->shared_cpu_map);
707 cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
710 dmi_check_system(sw_any_bug_dmi_table);
711 if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
712 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
713 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
716 if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
717 cpumask_clear(policy->cpus);
718 cpumask_set_cpu(cpu, policy->cpus);
719 cpumask_copy(data->freqdomain_cpus,
720 topology_sibling_cpumask(cpu));
721 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
722 pr_info_once(PFX "overriding BIOS provided _PSD data\n");
726 /* capability check */
727 if (perf->state_count <= 1) {
728 pr_debug("No P-States\n");
733 if (perf->control_register.space_id != perf->status_register.space_id) {
738 switch (perf->control_register.space_id) {
739 case ACPI_ADR_SPACE_SYSTEM_IO:
740 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
741 boot_cpu_data.x86 == 0xf) {
742 pr_debug("AMD K8 systems must use native drivers.\n");
746 pr_debug("SYSTEM IO addr space\n");
747 data->cpu_feature = SYSTEM_IO_CAPABLE;
749 case ACPI_ADR_SPACE_FIXED_HARDWARE:
750 pr_debug("HARDWARE addr space\n");
751 if (check_est_cpu(cpu)) {
752 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
755 if (check_amd_hwpstate_cpu(cpu)) {
756 data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
762 pr_debug("Unknown addr space %d\n",
763 (u32) (perf->control_register.space_id));
768 data->freq_table = kzalloc(sizeof(*data->freq_table) *
769 (perf->state_count+1), GFP_KERNEL);
770 if (!data->freq_table) {
775 /* detect transition latency */
776 policy->cpuinfo.transition_latency = 0;
777 for (i = 0; i < perf->state_count; i++) {
778 if ((perf->states[i].transition_latency * 1000) >
779 policy->cpuinfo.transition_latency)
780 policy->cpuinfo.transition_latency =
781 perf->states[i].transition_latency * 1000;
784 /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
785 if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
786 policy->cpuinfo.transition_latency > 20 * 1000) {
787 policy->cpuinfo.transition_latency = 20 * 1000;
788 printk_once(KERN_INFO
789 "P-state transition latency capped at 20 uS\n");
793 for (i = 0; i < perf->state_count; i++) {
794 if (i > 0 && perf->states[i].core_frequency >=
795 data->freq_table[valid_states-1].frequency / 1000)
798 data->freq_table[valid_states].driver_data = i;
799 data->freq_table[valid_states].frequency =
800 perf->states[i].core_frequency * 1000;
803 data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
806 result = cpufreq_table_validate_and_show(policy, data->freq_table);
810 if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
811 printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
813 switch (perf->control_register.space_id) {
814 case ACPI_ADR_SPACE_SYSTEM_IO:
816 * The core will not set policy->cur, because
817 * cpufreq_driver->get is NULL, so we need to set it here.
818 * However, we have to guess it, because the current speed is
819 * unknown and not detectable via IO ports.
821 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
823 case ACPI_ADR_SPACE_FIXED_HARDWARE:
824 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
830 /* notify BIOS that we exist */
831 acpi_processor_notify_smm(THIS_MODULE);
833 pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
834 for (i = 0; i < perf->state_count; i++)
835 pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
836 (i == perf->state ? '*' : ' '), i,
837 (u32) perf->states[i].core_frequency,
838 (u32) perf->states[i].power,
839 (u32) perf->states[i].transition_latency);
842 * the first call to ->target() should result in us actually
843 * writing something to the appropriate registers.
850 kfree(data->freq_table);
852 acpi_processor_unregister_performance(cpu);
854 free_cpumask_var(data->freqdomain_cpus);
857 policy->driver_data = NULL;
862 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
864 struct acpi_cpufreq_data *data = policy->driver_data;
866 pr_debug("acpi_cpufreq_cpu_exit\n");
869 policy->driver_data = NULL;
870 acpi_processor_unregister_performance(data->acpi_perf_cpu);
871 free_cpumask_var(data->freqdomain_cpus);
872 kfree(data->freq_table);
879 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
881 struct acpi_cpufreq_data *data = policy->driver_data;
883 pr_debug("acpi_cpufreq_resume\n");
890 static struct freq_attr *acpi_cpufreq_attr[] = {
891 &cpufreq_freq_attr_scaling_available_freqs,
893 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
899 static struct cpufreq_driver acpi_cpufreq_driver = {
900 .verify = cpufreq_generic_frequency_table_verify,
901 .target_index = acpi_cpufreq_target,
902 .bios_limit = acpi_processor_get_bios_limit,
903 .init = acpi_cpufreq_cpu_init,
904 .exit = acpi_cpufreq_cpu_exit,
905 .resume = acpi_cpufreq_resume,
906 .name = "acpi-cpufreq",
907 .attr = acpi_cpufreq_attr,
908 .set_boost = _store_boost,
911 static void __init acpi_cpufreq_boost_init(void)
913 if (boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)) {
919 acpi_cpufreq_driver.boost_supported = true;
920 acpi_cpufreq_driver.boost_enabled = boost_state(0);
922 cpu_notifier_register_begin();
924 /* Force all MSRs to the same value */
925 boost_set_msrs(acpi_cpufreq_driver.boost_enabled,
928 __register_cpu_notifier(&boost_nb);
930 cpu_notifier_register_done();
934 static void acpi_cpufreq_boost_exit(void)
937 unregister_cpu_notifier(&boost_nb);
944 static int __init acpi_cpufreq_init(void)
951 /* don't keep reloading if cpufreq_driver exists */
952 if (cpufreq_get_current_driver())
955 pr_debug("acpi_cpufreq_init\n");
957 ret = acpi_cpufreq_early_init();
961 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
962 /* this is a sysfs file with a strange name and an even stranger
963 * semantic - per CPU instantiation, but system global effect.
964 * Lets enable it only on AMD CPUs for compatibility reasons and
965 * only if configured. This is considered legacy code, which
966 * will probably be removed at some point in the future.
968 if (!check_amd_hwpstate_cpu(0)) {
969 struct freq_attr **attr;
971 pr_debug("CPB unsupported, do not expose it\n");
973 for (attr = acpi_cpufreq_attr; *attr; attr++)
980 acpi_cpufreq_boost_init();
982 ret = cpufreq_register_driver(&acpi_cpufreq_driver);
984 free_acpi_perf_data();
985 acpi_cpufreq_boost_exit();
990 static void __exit acpi_cpufreq_exit(void)
992 pr_debug("acpi_cpufreq_exit\n");
994 acpi_cpufreq_boost_exit();
996 cpufreq_unregister_driver(&acpi_cpufreq_driver);
998 free_acpi_perf_data();
1001 module_param(acpi_pstate_strict, uint, 0644);
1002 MODULE_PARM_DESC(acpi_pstate_strict,
1003 "value 0 or non-zero. non-zero -> strict ACPI checks are "
1004 "performed during frequency changes.");
1006 late_initcall(acpi_cpufreq_init);
1007 module_exit(acpi_cpufreq_exit);
1009 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
1010 X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1011 X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1014 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1016 static const struct acpi_device_id processor_device_ids[] = {
1017 {ACPI_PROCESSOR_OBJECT_HID, },
1018 {ACPI_PROCESSOR_DEVICE_HID, },
1021 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1023 MODULE_ALIAS("acpi");