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;
73 void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
74 u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
77 /* acpi_perf_data is a pointer to percpu data. */
78 static struct acpi_processor_performance __percpu *acpi_perf_data;
80 static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
82 return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
85 static struct cpufreq_driver acpi_cpufreq_driver;
87 static unsigned int acpi_pstate_strict;
88 static struct msr __percpu *msrs;
90 static bool boost_state(unsigned int cpu)
95 switch (boot_cpu_data.x86_vendor) {
96 case X86_VENDOR_INTEL:
97 rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
98 msr = lo | ((u64)hi << 32);
99 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
101 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
102 msr = lo | ((u64)hi << 32);
103 return !(msr & MSR_K7_HWCR_CPB_DIS);
108 static void boost_set_msrs(bool enable, const struct cpumask *cpumask)
114 switch (boot_cpu_data.x86_vendor) {
115 case X86_VENDOR_INTEL:
116 msr_addr = MSR_IA32_MISC_ENABLE;
117 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
120 msr_addr = MSR_K7_HWCR;
121 msr_mask = MSR_K7_HWCR_CPB_DIS;
127 rdmsr_on_cpus(cpumask, msr_addr, msrs);
129 for_each_cpu(cpu, cpumask) {
130 struct msr *reg = per_cpu_ptr(msrs, cpu);
137 wrmsr_on_cpus(cpumask, msr_addr, msrs);
140 static int set_boost(int val)
143 boost_set_msrs(val, cpu_online_mask);
145 pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
150 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
152 struct acpi_cpufreq_data *data = policy->driver_data;
157 return cpufreq_show_cpus(data->freqdomain_cpus, buf);
160 cpufreq_freq_attr_ro(freqdomain_cpus);
162 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
163 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
167 unsigned int val = 0;
169 if (!acpi_cpufreq_driver.set_boost)
172 ret = kstrtouint(buf, 10, &val);
181 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
183 return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
186 cpufreq_freq_attr_rw(cpb);
189 static int check_est_cpu(unsigned int cpuid)
191 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
193 return cpu_has(cpu, X86_FEATURE_EST);
196 static int check_amd_hwpstate_cpu(unsigned int cpuid)
198 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
200 return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
203 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
205 struct acpi_processor_performance *perf;
208 perf = to_perf_data(data);
210 for (i = 0; i < perf->state_count; i++) {
211 if (value == perf->states[i].status)
212 return data->freq_table[i].frequency;
217 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
219 struct cpufreq_frequency_table *pos;
220 struct acpi_processor_performance *perf;
222 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
223 msr &= AMD_MSR_RANGE;
225 msr &= INTEL_MSR_RANGE;
227 perf = to_perf_data(data);
229 cpufreq_for_each_entry(pos, data->freq_table)
230 if (msr == perf->states[pos->driver_data].status)
231 return pos->frequency;
232 return data->freq_table[0].frequency;
235 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
237 switch (data->cpu_feature) {
238 case SYSTEM_INTEL_MSR_CAPABLE:
239 case SYSTEM_AMD_MSR_CAPABLE:
240 return extract_msr(val, data);
241 case SYSTEM_IO_CAPABLE:
242 return extract_io(val, data);
248 u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
252 rdmsr(MSR_IA32_PERF_CTL, val, dummy);
256 void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
260 rdmsr(MSR_IA32_PERF_CTL, lo, hi);
261 lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
262 wrmsr(MSR_IA32_PERF_CTL, lo, hi);
265 u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
269 rdmsr(MSR_AMD_PERF_CTL, val, dummy);
273 void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
275 wrmsr(MSR_AMD_PERF_CTL, val, 0);
278 u32 cpu_freq_read_io(struct acpi_pct_register *reg)
282 acpi_os_read_port(reg->address, &val, reg->bit_width);
286 void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
288 acpi_os_write_port(reg->address, val, reg->bit_width);
292 struct acpi_pct_register *reg;
295 void (*write)(struct acpi_pct_register *reg, u32 val);
296 u32 (*read)(struct acpi_pct_register *reg);
300 /* Called via smp_call_function_single(), on the target CPU */
301 static void do_drv_read(void *_cmd)
303 struct drv_cmd *cmd = _cmd;
305 cmd->val = cmd->func.read(cmd->reg);
308 static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
310 struct acpi_processor_performance *perf = to_perf_data(data);
311 struct drv_cmd cmd = {
312 .reg = &perf->control_register,
313 .func.read = data->cpu_freq_read,
317 err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
318 WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */
322 /* Called via smp_call_function_many(), on the target CPUs */
323 static void do_drv_write(void *_cmd)
325 struct drv_cmd *cmd = _cmd;
327 cmd->func.write(cmd->reg, cmd->val);
330 static void drv_write(struct acpi_cpufreq_data *data,
331 const struct cpumask *mask, u32 val)
333 struct acpi_processor_performance *perf = to_perf_data(data);
334 struct drv_cmd cmd = {
335 .reg = &perf->control_register,
337 .func.write = data->cpu_freq_write,
341 this_cpu = get_cpu();
342 if (cpumask_test_cpu(this_cpu, mask))
345 smp_call_function_many(mask, do_drv_write, &cmd, 1);
349 static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
353 if (unlikely(cpumask_empty(mask)))
356 val = drv_read(data, mask);
358 pr_debug("get_cur_val = %u\n", val);
363 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
365 struct acpi_cpufreq_data *data;
366 struct cpufreq_policy *policy;
368 unsigned int cached_freq;
370 pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
372 policy = cpufreq_cpu_get_raw(cpu);
373 if (unlikely(!policy))
376 data = policy->driver_data;
377 if (unlikely(!data || !data->freq_table))
380 cached_freq = data->freq_table[to_perf_data(data)->state].frequency;
381 freq = extract_freq(get_cur_val(cpumask_of(cpu), data), data);
382 if (freq != cached_freq) {
384 * The dreaded BIOS frequency change behind our back.
385 * Force set the frequency on next target call.
390 pr_debug("cur freq = %u\n", freq);
395 static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
396 struct acpi_cpufreq_data *data)
398 unsigned int cur_freq;
401 for (i = 0; i < 100; i++) {
402 cur_freq = extract_freq(get_cur_val(mask, data), data);
403 if (cur_freq == freq)
410 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
413 struct acpi_cpufreq_data *data = policy->driver_data;
414 struct acpi_processor_performance *perf;
415 const struct cpumask *mask;
416 unsigned int next_perf_state = 0; /* Index into perf table */
419 if (unlikely(data == NULL || data->freq_table == NULL)) {
423 perf = to_perf_data(data);
424 next_perf_state = data->freq_table[index].driver_data;
425 if (perf->state == next_perf_state) {
426 if (unlikely(data->resume)) {
427 pr_debug("Called after resume, resetting to P%d\n",
431 pr_debug("Already at target state (P%d)\n",
438 * The core won't allow CPUs to go away until the governor has been
439 * stopped, so we can rely on the stability of policy->cpus.
441 mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
442 cpumask_of(policy->cpu) : policy->cpus;
444 drv_write(data, mask, perf->states[next_perf_state].control);
446 if (acpi_pstate_strict) {
447 if (!check_freqs(mask, data->freq_table[index].frequency,
449 pr_debug("acpi_cpufreq_target failed (%d)\n",
456 perf->state = next_perf_state;
462 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
464 struct acpi_processor_performance *perf;
466 perf = to_perf_data(data);
468 /* search the closest match to cpu_khz */
471 unsigned long freqn = perf->states[0].core_frequency * 1000;
473 for (i = 0; i < (perf->state_count-1); i++) {
475 freqn = perf->states[i+1].core_frequency * 1000;
476 if ((2 * cpu_khz) > (freqn + freq)) {
481 perf->state = perf->state_count-1;
484 /* assume CPU is at P0... */
486 return perf->states[0].core_frequency * 1000;
490 static void free_acpi_perf_data(void)
494 /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
495 for_each_possible_cpu(i)
496 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
498 free_percpu(acpi_perf_data);
501 static int boost_notify(struct notifier_block *nb, unsigned long action,
504 unsigned cpu = (long)hcpu;
505 const struct cpumask *cpumask;
507 cpumask = get_cpu_mask(cpu);
510 * Clear the boost-disable bit on the CPU_DOWN path so that
511 * this cpu cannot block the remaining ones from boosting. On
512 * the CPU_UP path we simply keep the boost-disable flag in
513 * sync with the current global state.
518 case CPU_UP_PREPARE_FROZEN:
519 boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
522 case CPU_DOWN_PREPARE:
523 case CPU_DOWN_PREPARE_FROZEN:
524 boost_set_msrs(1, cpumask);
535 static struct notifier_block boost_nb = {
536 .notifier_call = boost_notify,
540 * acpi_cpufreq_early_init - initialize ACPI P-States library
542 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
543 * in order to determine correct frequency and voltage pairings. We can
544 * do _PDC and _PSD and find out the processor dependency for the
545 * actual init that will happen later...
547 static int __init acpi_cpufreq_early_init(void)
550 pr_debug("acpi_cpufreq_early_init\n");
552 acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
553 if (!acpi_perf_data) {
554 pr_debug("Memory allocation error for acpi_perf_data.\n");
557 for_each_possible_cpu(i) {
558 if (!zalloc_cpumask_var_node(
559 &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
560 GFP_KERNEL, cpu_to_node(i))) {
562 /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
563 free_acpi_perf_data();
568 /* Do initialization in ACPI core */
569 acpi_processor_preregister_performance(acpi_perf_data);
575 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
576 * or do it in BIOS firmware and won't inform about it to OS. If not
577 * detected, this has a side effect of making CPU run at a different speed
578 * than OS intended it to run at. Detect it and handle it cleanly.
580 static int bios_with_sw_any_bug;
582 static int sw_any_bug_found(const struct dmi_system_id *d)
584 bios_with_sw_any_bug = 1;
588 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
590 .callback = sw_any_bug_found,
591 .ident = "Supermicro Server X6DLP",
593 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
594 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
595 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
601 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
603 /* Intel Xeon Processor 7100 Series Specification Update
604 * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
605 * AL30: A Machine Check Exception (MCE) Occurring during an
606 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
607 * Both Processor Cores to Lock Up. */
608 if (c->x86_vendor == X86_VENDOR_INTEL) {
609 if ((c->x86 == 15) &&
610 (c->x86_model == 6) &&
611 (c->x86_mask == 8)) {
612 printk(KERN_INFO "acpi-cpufreq: Intel(R) "
613 "Xeon(R) 7100 Errata AL30, processors may "
614 "lock up on frequency changes: disabling "
623 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
626 unsigned int valid_states = 0;
627 unsigned int cpu = policy->cpu;
628 struct acpi_cpufreq_data *data;
629 unsigned int result = 0;
630 struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
631 struct acpi_processor_performance *perf;
633 static int blacklisted;
636 pr_debug("acpi_cpufreq_cpu_init\n");
641 blacklisted = acpi_cpufreq_blacklist(c);
646 data = kzalloc(sizeof(*data), GFP_KERNEL);
650 if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
655 perf = per_cpu_ptr(acpi_perf_data, cpu);
656 data->acpi_perf_cpu = cpu;
657 policy->driver_data = data;
659 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
660 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
662 result = acpi_processor_register_performance(perf, cpu);
666 policy->shared_type = perf->shared_type;
669 * Will let policy->cpus know about dependency only when software
670 * coordination is required.
672 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
673 policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
674 cpumask_copy(policy->cpus, perf->shared_cpu_map);
676 cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
679 dmi_check_system(sw_any_bug_dmi_table);
680 if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
681 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
682 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
685 if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
686 cpumask_clear(policy->cpus);
687 cpumask_set_cpu(cpu, policy->cpus);
688 cpumask_copy(data->freqdomain_cpus,
689 topology_sibling_cpumask(cpu));
690 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
691 pr_info_once(PFX "overriding BIOS provided _PSD data\n");
695 /* capability check */
696 if (perf->state_count <= 1) {
697 pr_debug("No P-States\n");
702 if (perf->control_register.space_id != perf->status_register.space_id) {
707 switch (perf->control_register.space_id) {
708 case ACPI_ADR_SPACE_SYSTEM_IO:
709 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
710 boot_cpu_data.x86 == 0xf) {
711 pr_debug("AMD K8 systems must use native drivers.\n");
715 pr_debug("SYSTEM IO addr space\n");
716 data->cpu_feature = SYSTEM_IO_CAPABLE;
717 data->cpu_freq_read = cpu_freq_read_io;
718 data->cpu_freq_write = cpu_freq_write_io;
720 case ACPI_ADR_SPACE_FIXED_HARDWARE:
721 pr_debug("HARDWARE addr space\n");
722 if (check_est_cpu(cpu)) {
723 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
724 data->cpu_freq_read = cpu_freq_read_intel;
725 data->cpu_freq_write = cpu_freq_write_intel;
728 if (check_amd_hwpstate_cpu(cpu)) {
729 data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
730 data->cpu_freq_read = cpu_freq_read_amd;
731 data->cpu_freq_write = cpu_freq_write_amd;
737 pr_debug("Unknown addr space %d\n",
738 (u32) (perf->control_register.space_id));
743 data->freq_table = kzalloc(sizeof(*data->freq_table) *
744 (perf->state_count+1), GFP_KERNEL);
745 if (!data->freq_table) {
750 /* detect transition latency */
751 policy->cpuinfo.transition_latency = 0;
752 for (i = 0; i < perf->state_count; i++) {
753 if ((perf->states[i].transition_latency * 1000) >
754 policy->cpuinfo.transition_latency)
755 policy->cpuinfo.transition_latency =
756 perf->states[i].transition_latency * 1000;
759 /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
760 if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
761 policy->cpuinfo.transition_latency > 20 * 1000) {
762 policy->cpuinfo.transition_latency = 20 * 1000;
763 printk_once(KERN_INFO
764 "P-state transition latency capped at 20 uS\n");
768 for (i = 0; i < perf->state_count; i++) {
769 if (i > 0 && perf->states[i].core_frequency >=
770 data->freq_table[valid_states-1].frequency / 1000)
773 data->freq_table[valid_states].driver_data = i;
774 data->freq_table[valid_states].frequency =
775 perf->states[i].core_frequency * 1000;
778 data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
781 result = cpufreq_table_validate_and_show(policy, data->freq_table);
785 if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
786 printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
788 switch (perf->control_register.space_id) {
789 case ACPI_ADR_SPACE_SYSTEM_IO:
791 * The core will not set policy->cur, because
792 * cpufreq_driver->get is NULL, so we need to set it here.
793 * However, we have to guess it, because the current speed is
794 * unknown and not detectable via IO ports.
796 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
798 case ACPI_ADR_SPACE_FIXED_HARDWARE:
799 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
805 /* notify BIOS that we exist */
806 acpi_processor_notify_smm(THIS_MODULE);
808 pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
809 for (i = 0; i < perf->state_count; i++)
810 pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
811 (i == perf->state ? '*' : ' '), i,
812 (u32) perf->states[i].core_frequency,
813 (u32) perf->states[i].power,
814 (u32) perf->states[i].transition_latency);
817 * the first call to ->target() should result in us actually
818 * writing something to the appropriate registers.
825 kfree(data->freq_table);
827 acpi_processor_unregister_performance(cpu);
829 free_cpumask_var(data->freqdomain_cpus);
832 policy->driver_data = NULL;
837 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
839 struct acpi_cpufreq_data *data = policy->driver_data;
841 pr_debug("acpi_cpufreq_cpu_exit\n");
844 policy->driver_data = NULL;
845 acpi_processor_unregister_performance(data->acpi_perf_cpu);
846 free_cpumask_var(data->freqdomain_cpus);
847 kfree(data->freq_table);
854 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
856 struct acpi_cpufreq_data *data = policy->driver_data;
858 pr_debug("acpi_cpufreq_resume\n");
865 static struct freq_attr *acpi_cpufreq_attr[] = {
866 &cpufreq_freq_attr_scaling_available_freqs,
868 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
874 static struct cpufreq_driver acpi_cpufreq_driver = {
875 .verify = cpufreq_generic_frequency_table_verify,
876 .target_index = acpi_cpufreq_target,
877 .bios_limit = acpi_processor_get_bios_limit,
878 .init = acpi_cpufreq_cpu_init,
879 .exit = acpi_cpufreq_cpu_exit,
880 .resume = acpi_cpufreq_resume,
881 .name = "acpi-cpufreq",
882 .attr = acpi_cpufreq_attr,
885 static void __init acpi_cpufreq_boost_init(void)
887 if (boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)) {
893 acpi_cpufreq_driver.set_boost = set_boost;
894 acpi_cpufreq_driver.boost_enabled = boost_state(0);
896 cpu_notifier_register_begin();
898 /* Force all MSRs to the same value */
899 boost_set_msrs(acpi_cpufreq_driver.boost_enabled,
902 __register_cpu_notifier(&boost_nb);
904 cpu_notifier_register_done();
908 static void acpi_cpufreq_boost_exit(void)
911 unregister_cpu_notifier(&boost_nb);
918 static int __init acpi_cpufreq_init(void)
925 /* don't keep reloading if cpufreq_driver exists */
926 if (cpufreq_get_current_driver())
929 pr_debug("acpi_cpufreq_init\n");
931 ret = acpi_cpufreq_early_init();
935 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
936 /* this is a sysfs file with a strange name and an even stranger
937 * semantic - per CPU instantiation, but system global effect.
938 * Lets enable it only on AMD CPUs for compatibility reasons and
939 * only if configured. This is considered legacy code, which
940 * will probably be removed at some point in the future.
942 if (!check_amd_hwpstate_cpu(0)) {
943 struct freq_attr **attr;
945 pr_debug("CPB unsupported, do not expose it\n");
947 for (attr = acpi_cpufreq_attr; *attr; attr++)
954 acpi_cpufreq_boost_init();
956 ret = cpufreq_register_driver(&acpi_cpufreq_driver);
958 free_acpi_perf_data();
959 acpi_cpufreq_boost_exit();
964 static void __exit acpi_cpufreq_exit(void)
966 pr_debug("acpi_cpufreq_exit\n");
968 acpi_cpufreq_boost_exit();
970 cpufreq_unregister_driver(&acpi_cpufreq_driver);
972 free_acpi_perf_data();
975 module_param(acpi_pstate_strict, uint, 0644);
976 MODULE_PARM_DESC(acpi_pstate_strict,
977 "value 0 or non-zero. non-zero -> strict ACPI checks are "
978 "performed during frequency changes.");
980 late_initcall(acpi_cpufreq_init);
981 module_exit(acpi_cpufreq_exit);
983 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
984 X86_FEATURE_MATCH(X86_FEATURE_ACPI),
985 X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
988 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
990 static const struct acpi_device_id processor_device_ids[] = {
991 {ACPI_PROCESSOR_OBJECT_HID, },
992 {ACPI_PROCESSOR_DEVICE_HID, },
995 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
997 MODULE_ALIAS("acpi");