2 * acpi-cpufreq.c - ACPI Processor P-States Driver
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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
40 #include <linux/acpi.h>
42 #include <linux/delay.h>
43 #include <linux/uaccess.h>
45 #include <acpi/processor.h>
48 #include <asm/processor.h>
49 #include <asm/cpufeature.h>
51 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
52 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
53 MODULE_LICENSE("GPL");
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 {
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);
76 /* acpi_perf_data is a pointer to percpu data. */
77 static struct acpi_processor_performance __percpu *acpi_perf_data;
79 static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
81 return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
84 static struct cpufreq_driver acpi_cpufreq_driver;
86 static unsigned int acpi_pstate_strict;
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 int boost_set_msr(bool enable)
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;
117 msr_addr = MSR_K7_HWCR;
118 msr_mask = MSR_K7_HWCR_CPB_DIS;
124 rdmsrl(msr_addr, val);
131 wrmsrl(msr_addr, val);
135 static void boost_set_msr_each(void *p_en)
137 bool enable = (bool) p_en;
139 boost_set_msr(enable);
142 static int set_boost(int val)
145 on_each_cpu(boost_set_msr_each, (void *)(long)val, 1);
147 pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
152 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
154 struct acpi_cpufreq_data *data = policy->driver_data;
159 return cpufreq_show_cpus(data->freqdomain_cpus, buf);
162 cpufreq_freq_attr_ro(freqdomain_cpus);
164 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
165 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
169 unsigned int val = 0;
171 if (!acpi_cpufreq_driver.set_boost)
174 ret = kstrtouint(buf, 10, &val);
183 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
185 return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
188 cpufreq_freq_attr_rw(cpb);
191 static int check_est_cpu(unsigned int cpuid)
193 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
195 return cpu_has(cpu, X86_FEATURE_EST);
198 static int check_amd_hwpstate_cpu(unsigned int cpuid)
200 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
202 return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
205 static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
207 struct acpi_cpufreq_data *data = policy->driver_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 policy->freq_table[i].frequency;
220 static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
222 struct acpi_cpufreq_data *data = policy->driver_data;
223 struct cpufreq_frequency_table *pos;
224 struct acpi_processor_performance *perf;
226 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
227 msr &= AMD_MSR_RANGE;
229 msr &= INTEL_MSR_RANGE;
231 perf = to_perf_data(data);
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;
239 static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
241 struct acpi_cpufreq_data *data = policy->driver_data;
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);
254 static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
258 rdmsr(MSR_IA32_PERF_CTL, val, dummy);
262 static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
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);
271 static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
275 rdmsr(MSR_AMD_PERF_CTL, val, dummy);
279 static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
281 wrmsr(MSR_AMD_PERF_CTL, val, 0);
284 static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
288 acpi_os_read_port(reg->address, &val, reg->bit_width);
292 static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
294 acpi_os_write_port(reg->address, val, reg->bit_width);
298 struct acpi_pct_register *reg;
301 void (*write)(struct acpi_pct_register *reg, u32 val);
302 u32 (*read)(struct acpi_pct_register *reg);
306 /* Called via smp_call_function_single(), on the target CPU */
307 static void do_drv_read(void *_cmd)
309 struct drv_cmd *cmd = _cmd;
311 cmd->val = cmd->func.read(cmd->reg);
314 static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
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,
323 err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
324 WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */
328 /* Called via smp_call_function_many(), on the target CPUs */
329 static void do_drv_write(void *_cmd)
331 struct drv_cmd *cmd = _cmd;
333 cmd->func.write(cmd->reg, cmd->val);
336 static void drv_write(struct acpi_cpufreq_data *data,
337 const struct cpumask *mask, u32 val)
339 struct acpi_processor_performance *perf = to_perf_data(data);
340 struct drv_cmd cmd = {
341 .reg = &perf->control_register,
343 .func.write = data->cpu_freq_write,
347 this_cpu = get_cpu();
348 if (cpumask_test_cpu(this_cpu, mask))
351 smp_call_function_many(mask, do_drv_write, &cmd, 1);
355 static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
359 if (unlikely(cpumask_empty(mask)))
362 val = drv_read(data, mask);
364 pr_debug("get_cur_val = %u\n", val);
369 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
371 struct acpi_cpufreq_data *data;
372 struct cpufreq_policy *policy;
374 unsigned int cached_freq;
376 pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
378 policy = cpufreq_cpu_get_raw(cpu);
379 if (unlikely(!policy))
382 data = policy->driver_data;
383 if (unlikely(!data || !policy->freq_table))
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) {
390 * The dreaded BIOS frequency change behind our back.
391 * Force set the frequency on next target call.
396 pr_debug("cur freq = %u\n", freq);
401 static unsigned int check_freqs(struct cpufreq_policy *policy,
402 const struct cpumask *mask, unsigned int freq)
404 struct acpi_cpufreq_data *data = policy->driver_data;
405 unsigned int cur_freq;
408 for (i = 0; i < 100; i++) {
409 cur_freq = extract_freq(policy, get_cur_val(mask, data));
410 if (cur_freq == freq)
417 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
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 */
426 if (unlikely(!data)) {
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",
438 pr_debug("Already at target state (P%d)\n",
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.
448 mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
449 cpumask_of(policy->cpu) : policy->cpus;
451 drv_write(data, mask, perf->states[next_perf_state].control);
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",
463 perf->state = next_perf_state;
468 static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
469 unsigned int target_freq)
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;
477 * Find the closest frequency above target_freq.
479 if (policy->cached_target_freq == target_freq)
480 index = policy->cached_resolved_idx;
482 index = cpufreq_table_find_index_dl(policy, target_freq);
484 entry = &policy->freq_table[index];
485 next_freq = entry->frequency;
486 next_perf_state = entry->driver_data;
488 perf = to_perf_data(data);
489 if (perf->state == next_perf_state) {
490 if (unlikely(data->resume))
496 data->cpu_freq_write(&perf->control_register,
497 perf->states[next_perf_state].control);
498 perf->state = next_perf_state;
503 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
505 struct acpi_processor_performance *perf;
507 perf = to_perf_data(data);
509 /* search the closest match to cpu_khz */
512 unsigned long freqn = perf->states[0].core_frequency * 1000;
514 for (i = 0; i < (perf->state_count-1); i++) {
516 freqn = perf->states[i+1].core_frequency * 1000;
517 if ((2 * cpu_khz) > (freqn + freq)) {
522 perf->state = perf->state_count-1;
525 /* assume CPU is at P0... */
527 return perf->states[0].core_frequency * 1000;
531 static void free_acpi_perf_data(void)
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)
539 free_percpu(acpi_perf_data);
542 static int cpufreq_boost_online(unsigned int cpu)
545 * On the CPU_UP path we simply keep the boost-disable flag
546 * in sync with the current global state.
548 return boost_set_msr(acpi_cpufreq_driver.boost_enabled);
551 static int cpufreq_boost_down_prep(unsigned int cpu)
554 * Clear the boost-disable bit on the CPU_DOWN path so that
555 * this cpu cannot block the remaining ones from boosting.
557 return boost_set_msr(1);
561 * acpi_cpufreq_early_init - initialize ACPI P-States library
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...
568 static int __init acpi_cpufreq_early_init(void)
571 pr_debug("acpi_cpufreq_early_init\n");
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");
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))) {
583 /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
584 free_acpi_perf_data();
589 /* Do initialization in ACPI core */
590 acpi_processor_preregister_performance(acpi_perf_data);
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.
601 static int bios_with_sw_any_bug;
603 static int sw_any_bug_found(const struct dmi_system_id *d)
605 bios_with_sw_any_bug = 1;
609 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
611 .callback = sw_any_bug_found,
612 .ident = "Supermicro Server X6DLP",
614 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
615 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
616 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
622 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
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_stepping == 8)) {
633 pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
641 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
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;
652 static int blacklisted;
655 pr_debug("acpi_cpufreq_cpu_init\n");
660 blacklisted = acpi_cpufreq_blacklist(c);
665 data = kzalloc(sizeof(*data), GFP_KERNEL);
669 if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
674 perf = per_cpu_ptr(acpi_perf_data, cpu);
675 data->acpi_perf_cpu = cpu;
676 policy->driver_data = data;
678 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
679 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
681 result = acpi_processor_register_performance(perf, cpu);
685 policy->shared_type = perf->shared_type;
688 * Will let policy->cpus know about dependency only when software
689 * coordination is required.
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);
695 cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
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));
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");
714 /* capability check */
715 if (perf->state_count <= 1) {
716 pr_debug("No P-States\n");
721 if (perf->control_register.space_id != perf->status_register.space_id) {
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");
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;
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;
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;
756 pr_debug("Unknown addr space %d\n",
757 (u32) (perf->control_register.space_id));
762 freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),
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;
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");
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)
791 freq_table[valid_states].driver_data = i;
792 freq_table[valid_states].frequency =
793 perf->states[i].core_frequency * 1000;
796 freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
797 policy->freq_table = freq_table;
800 switch (perf->control_register.space_id) {
801 case ACPI_ADR_SPACE_SYSTEM_IO:
803 * The core will not set policy->cur, because
804 * cpufreq_driver->get is NULL, so we need to set it here.
805 * However, we have to guess it, because the current speed is
806 * unknown and not detectable via IO ports.
808 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
810 case ACPI_ADR_SPACE_FIXED_HARDWARE:
811 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
817 /* notify BIOS that we exist */
818 acpi_processor_notify_smm(THIS_MODULE);
820 pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
821 for (i = 0; i < perf->state_count; i++)
822 pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
823 (i == perf->state ? '*' : ' '), i,
824 (u32) perf->states[i].core_frequency,
825 (u32) perf->states[i].power,
826 (u32) perf->states[i].transition_latency);
829 * the first call to ->target() should result in us actually
830 * writing something to the appropriate registers.
834 policy->fast_switch_possible = !acpi_pstate_strict &&
835 !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
840 acpi_processor_unregister_performance(cpu);
842 free_cpumask_var(data->freqdomain_cpus);
845 policy->driver_data = NULL;
850 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
852 struct acpi_cpufreq_data *data = policy->driver_data;
854 pr_debug("acpi_cpufreq_cpu_exit\n");
856 policy->fast_switch_possible = false;
857 policy->driver_data = NULL;
858 acpi_processor_unregister_performance(data->acpi_perf_cpu);
859 free_cpumask_var(data->freqdomain_cpus);
860 kfree(policy->freq_table);
866 static void acpi_cpufreq_cpu_ready(struct cpufreq_policy *policy)
868 struct acpi_processor_performance *perf = per_cpu_ptr(acpi_perf_data,
871 if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
872 pr_warn(FW_WARN "P-state 0 is not max freq\n");
875 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
877 struct acpi_cpufreq_data *data = policy->driver_data;
879 pr_debug("acpi_cpufreq_resume\n");
886 static struct freq_attr *acpi_cpufreq_attr[] = {
887 &cpufreq_freq_attr_scaling_available_freqs,
889 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
895 static struct cpufreq_driver acpi_cpufreq_driver = {
896 .verify = cpufreq_generic_frequency_table_verify,
897 .target_index = acpi_cpufreq_target,
898 .fast_switch = acpi_cpufreq_fast_switch,
899 .bios_limit = acpi_processor_get_bios_limit,
900 .init = acpi_cpufreq_cpu_init,
901 .exit = acpi_cpufreq_cpu_exit,
902 .ready = acpi_cpufreq_cpu_ready,
903 .resume = acpi_cpufreq_resume,
904 .name = "acpi-cpufreq",
905 .attr = acpi_cpufreq_attr,
908 static enum cpuhp_state acpi_cpufreq_online;
910 static void __init acpi_cpufreq_boost_init(void)
914 if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)))
917 acpi_cpufreq_driver.set_boost = set_boost;
918 acpi_cpufreq_driver.boost_enabled = boost_state(0);
921 * This calls the online callback on all online cpu and forces all
922 * MSRs to the same value.
924 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online",
925 cpufreq_boost_online, cpufreq_boost_down_prep);
927 pr_err("acpi_cpufreq: failed to register hotplug callbacks\n");
930 acpi_cpufreq_online = ret;
933 static void acpi_cpufreq_boost_exit(void)
935 if (acpi_cpufreq_online > 0)
936 cpuhp_remove_state_nocalls(acpi_cpufreq_online);
939 static int __init acpi_cpufreq_init(void)
946 /* don't keep reloading if cpufreq_driver exists */
947 if (cpufreq_get_current_driver())
950 pr_debug("acpi_cpufreq_init\n");
952 ret = acpi_cpufreq_early_init();
956 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
957 /* this is a sysfs file with a strange name and an even stranger
958 * semantic - per CPU instantiation, but system global effect.
959 * Lets enable it only on AMD CPUs for compatibility reasons and
960 * only if configured. This is considered legacy code, which
961 * will probably be removed at some point in the future.
963 if (!check_amd_hwpstate_cpu(0)) {
964 struct freq_attr **attr;
966 pr_debug("CPB unsupported, do not expose it\n");
968 for (attr = acpi_cpufreq_attr; *attr; attr++)
975 acpi_cpufreq_boost_init();
977 ret = cpufreq_register_driver(&acpi_cpufreq_driver);
979 free_acpi_perf_data();
980 acpi_cpufreq_boost_exit();
985 static void __exit acpi_cpufreq_exit(void)
987 pr_debug("acpi_cpufreq_exit\n");
989 acpi_cpufreq_boost_exit();
991 cpufreq_unregister_driver(&acpi_cpufreq_driver);
993 free_acpi_perf_data();
996 module_param(acpi_pstate_strict, uint, 0644);
997 MODULE_PARM_DESC(acpi_pstate_strict,
998 "value 0 or non-zero. non-zero -> strict ACPI checks are "
999 "performed during frequency changes.");
1001 late_initcall(acpi_cpufreq_init);
1002 module_exit(acpi_cpufreq_exit);
1004 static const struct x86_cpu_id acpi_cpufreq_ids[] = {
1005 X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1006 X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1009 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1011 static const struct acpi_device_id processor_device_ids[] = {
1012 {ACPI_PROCESSOR_OBJECT_HID, },
1013 {ACPI_PROCESSOR_DEVICE_HID, },
1016 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1018 MODULE_ALIAS("acpi");