Merge tag 'trace-printf-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...
[drm/drm-misc.git] / drivers / cpufreq / acpi-cpufreq.c
blobc9ebacf5c88e2448cbe952da1946d4ec941a5b1c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * acpi-cpufreq.c - ACPI Processor P-States Driver
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
8 * Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
9 */
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/smp.h>
17 #include <linux/sched.h>
18 #include <linux/cpufreq.h>
19 #include <linux/compiler.h>
20 #include <linux/dmi.h>
21 #include <linux/slab.h>
22 #include <linux/string_helpers.h>
23 #include <linux/platform_device.h>
25 #include <linux/acpi.h>
26 #include <linux/io.h>
27 #include <linux/delay.h>
28 #include <linux/uaccess.h>
30 #include <acpi/processor.h>
31 #include <acpi/cppc_acpi.h>
33 #include <asm/msr.h>
34 #include <asm/processor.h>
35 #include <asm/cpufeature.h>
36 #include <asm/cpu_device_id.h>
38 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
39 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
40 MODULE_LICENSE("GPL");
42 enum {
43 UNDEFINED_CAPABLE = 0,
44 SYSTEM_INTEL_MSR_CAPABLE,
45 SYSTEM_AMD_MSR_CAPABLE,
46 SYSTEM_IO_CAPABLE,
49 #define INTEL_MSR_RANGE (0xffff)
50 #define AMD_MSR_RANGE (0x7)
51 #define HYGON_MSR_RANGE (0x7)
53 struct acpi_cpufreq_data {
54 unsigned int resume;
55 unsigned int cpu_feature;
56 unsigned int acpi_perf_cpu;
57 cpumask_var_t freqdomain_cpus;
58 void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
59 u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
62 /* acpi_perf_data is a pointer to percpu data. */
63 static struct acpi_processor_performance __percpu *acpi_perf_data;
65 static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
67 return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
70 static struct cpufreq_driver acpi_cpufreq_driver;
72 static unsigned int acpi_pstate_strict;
74 static bool boost_state(unsigned int cpu)
76 u64 msr;
78 switch (boot_cpu_data.x86_vendor) {
79 case X86_VENDOR_INTEL:
80 case X86_VENDOR_CENTAUR:
81 case X86_VENDOR_ZHAOXIN:
82 rdmsrl_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &msr);
83 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
84 case X86_VENDOR_HYGON:
85 case X86_VENDOR_AMD:
86 rdmsrl_on_cpu(cpu, MSR_K7_HWCR, &msr);
87 return !(msr & MSR_K7_HWCR_CPB_DIS);
89 return false;
92 static int boost_set_msr(bool enable)
94 u32 msr_addr;
95 u64 msr_mask, val;
97 switch (boot_cpu_data.x86_vendor) {
98 case X86_VENDOR_INTEL:
99 case X86_VENDOR_CENTAUR:
100 case X86_VENDOR_ZHAOXIN:
101 msr_addr = MSR_IA32_MISC_ENABLE;
102 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
103 break;
104 case X86_VENDOR_HYGON:
105 case X86_VENDOR_AMD:
106 msr_addr = MSR_K7_HWCR;
107 msr_mask = MSR_K7_HWCR_CPB_DIS;
108 break;
109 default:
110 return -EINVAL;
113 rdmsrl(msr_addr, val);
115 if (enable)
116 val &= ~msr_mask;
117 else
118 val |= msr_mask;
120 wrmsrl(msr_addr, val);
121 return 0;
124 static void boost_set_msr_each(void *p_en)
126 bool enable = (bool) p_en;
128 boost_set_msr(enable);
131 static int set_boost(struct cpufreq_policy *policy, int val)
133 on_each_cpu_mask(policy->cpus, boost_set_msr_each,
134 (void *)(long)val, 1);
135 pr_debug("CPU %*pbl: Core Boosting %s.\n",
136 cpumask_pr_args(policy->cpus), str_enabled_disabled(val));
138 return 0;
141 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
143 struct acpi_cpufreq_data *data = policy->driver_data;
145 if (unlikely(!data))
146 return -ENODEV;
148 return cpufreq_show_cpus(data->freqdomain_cpus, buf);
151 cpufreq_freq_attr_ro(freqdomain_cpus);
153 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
154 static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
155 size_t count)
157 int ret;
158 unsigned int val = 0;
160 if (!acpi_cpufreq_driver.set_boost)
161 return -EINVAL;
163 ret = kstrtouint(buf, 10, &val);
164 if (ret || val > 1)
165 return -EINVAL;
167 cpus_read_lock();
168 set_boost(policy, val);
169 cpus_read_unlock();
171 return count;
174 static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
176 return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
179 cpufreq_freq_attr_rw(cpb);
180 #endif
182 static int check_est_cpu(unsigned int cpuid)
184 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
186 return cpu_has(cpu, X86_FEATURE_EST);
189 static int check_amd_hwpstate_cpu(unsigned int cpuid)
191 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
193 return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
196 static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
198 struct acpi_cpufreq_data *data = policy->driver_data;
199 struct acpi_processor_performance *perf;
200 int i;
202 perf = to_perf_data(data);
204 for (i = 0; i < perf->state_count; i++) {
205 if (value == perf->states[i].status)
206 return policy->freq_table[i].frequency;
208 return 0;
211 static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
213 struct acpi_cpufreq_data *data = policy->driver_data;
214 struct cpufreq_frequency_table *pos;
215 struct acpi_processor_performance *perf;
217 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
218 msr &= AMD_MSR_RANGE;
219 else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
220 msr &= HYGON_MSR_RANGE;
221 else
222 msr &= INTEL_MSR_RANGE;
224 perf = to_perf_data(data);
226 cpufreq_for_each_entry(pos, policy->freq_table)
227 if (msr == perf->states[pos->driver_data].status)
228 return pos->frequency;
229 return policy->freq_table[0].frequency;
232 static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
234 struct acpi_cpufreq_data *data = policy->driver_data;
236 switch (data->cpu_feature) {
237 case SYSTEM_INTEL_MSR_CAPABLE:
238 case SYSTEM_AMD_MSR_CAPABLE:
239 return extract_msr(policy, val);
240 case SYSTEM_IO_CAPABLE:
241 return extract_io(policy, val);
242 default:
243 return 0;
247 static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
249 u32 val, dummy __always_unused;
251 rdmsr(MSR_IA32_PERF_CTL, val, dummy);
252 return val;
255 static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
257 u32 lo, hi;
259 rdmsr(MSR_IA32_PERF_CTL, lo, hi);
260 lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
261 wrmsr(MSR_IA32_PERF_CTL, lo, hi);
264 static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
266 u32 val, dummy __always_unused;
268 rdmsr(MSR_AMD_PERF_CTL, val, dummy);
269 return val;
272 static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
274 wrmsr(MSR_AMD_PERF_CTL, val, 0);
277 static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
279 u32 val;
281 acpi_os_read_port(reg->address, &val, reg->bit_width);
282 return val;
285 static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
287 acpi_os_write_port(reg->address, val, reg->bit_width);
290 struct drv_cmd {
291 struct acpi_pct_register *reg;
292 u32 val;
293 union {
294 void (*write)(struct acpi_pct_register *reg, u32 val);
295 u32 (*read)(struct acpi_pct_register *reg);
296 } func;
299 /* Called via smp_call_function_single(), on the target CPU */
300 static void do_drv_read(void *_cmd)
302 struct drv_cmd *cmd = _cmd;
304 cmd->val = cmd->func.read(cmd->reg);
307 static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
309 struct acpi_processor_performance *perf = to_perf_data(data);
310 struct drv_cmd cmd = {
311 .reg = &perf->control_register,
312 .func.read = data->cpu_freq_read,
314 int err;
316 err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
317 WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */
318 return cmd.val;
321 /* Called via smp_call_function_many(), on the target CPUs */
322 static void do_drv_write(void *_cmd)
324 struct drv_cmd *cmd = _cmd;
326 cmd->func.write(cmd->reg, cmd->val);
329 static void drv_write(struct acpi_cpufreq_data *data,
330 const struct cpumask *mask, u32 val)
332 struct acpi_processor_performance *perf = to_perf_data(data);
333 struct drv_cmd cmd = {
334 .reg = &perf->control_register,
335 .val = val,
336 .func.write = data->cpu_freq_write,
338 int this_cpu;
340 this_cpu = get_cpu();
341 if (cpumask_test_cpu(this_cpu, mask))
342 do_drv_write(&cmd);
344 smp_call_function_many(mask, do_drv_write, &cmd, 1);
345 put_cpu();
348 static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
350 u32 val;
352 if (unlikely(cpumask_empty(mask)))
353 return 0;
355 val = drv_read(data, mask);
357 pr_debug("%s = %u\n", __func__, val);
359 return val;
362 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
364 struct acpi_cpufreq_data *data;
365 struct cpufreq_policy *policy;
366 unsigned int freq;
367 unsigned int cached_freq;
369 pr_debug("%s (%d)\n", __func__, cpu);
371 policy = cpufreq_cpu_get_raw(cpu);
372 if (unlikely(!policy))
373 return 0;
375 data = policy->driver_data;
376 if (unlikely(!data || !policy->freq_table))
377 return 0;
379 cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
380 freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
381 if (freq != cached_freq) {
383 * The dreaded BIOS frequency change behind our back.
384 * Force set the frequency on next target call.
386 data->resume = 1;
389 pr_debug("cur freq = %u\n", freq);
391 return freq;
394 static unsigned int check_freqs(struct cpufreq_policy *policy,
395 const struct cpumask *mask, unsigned int freq)
397 struct acpi_cpufreq_data *data = policy->driver_data;
398 unsigned int cur_freq;
399 unsigned int i;
401 for (i = 0; i < 100; i++) {
402 cur_freq = extract_freq(policy, get_cur_val(mask, data));
403 if (cur_freq == freq)
404 return 1;
405 udelay(10);
407 return 0;
410 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
411 unsigned int index)
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 */
417 int result = 0;
419 if (unlikely(!data)) {
420 return -ENODEV;
423 perf = to_perf_data(data);
424 next_perf_state = policy->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",
428 next_perf_state);
429 data->resume = 0;
430 } else {
431 pr_debug("Already at target state (P%d)\n",
432 next_perf_state);
433 return 0;
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(policy, mask,
448 policy->freq_table[index].frequency)) {
449 pr_debug("%s (%d)\n", __func__, policy->cpu);
450 result = -EAGAIN;
454 if (!result)
455 perf->state = next_perf_state;
457 return result;
460 static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
461 unsigned int target_freq)
463 struct acpi_cpufreq_data *data = policy->driver_data;
464 struct acpi_processor_performance *perf;
465 struct cpufreq_frequency_table *entry;
466 unsigned int next_perf_state, next_freq, index;
469 * Find the closest frequency above target_freq.
471 if (policy->cached_target_freq == target_freq)
472 index = policy->cached_resolved_idx;
473 else
474 index = cpufreq_table_find_index_dl(policy, target_freq,
475 false);
477 entry = &policy->freq_table[index];
478 next_freq = entry->frequency;
479 next_perf_state = entry->driver_data;
481 perf = to_perf_data(data);
482 if (perf->state == next_perf_state) {
483 if (unlikely(data->resume))
484 data->resume = 0;
485 else
486 return next_freq;
489 data->cpu_freq_write(&perf->control_register,
490 perf->states[next_perf_state].control);
491 perf->state = next_perf_state;
492 return next_freq;
495 static unsigned long
496 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
498 struct acpi_processor_performance *perf;
500 perf = to_perf_data(data);
501 if (cpu_khz) {
502 /* search the closest match to cpu_khz */
503 unsigned int i;
504 unsigned long freq;
505 unsigned long freqn = perf->states[0].core_frequency * 1000;
507 for (i = 0; i < (perf->state_count-1); i++) {
508 freq = freqn;
509 freqn = perf->states[i+1].core_frequency * 1000;
510 if ((2 * cpu_khz) > (freqn + freq)) {
511 perf->state = i;
512 return freq;
515 perf->state = perf->state_count-1;
516 return freqn;
517 } else {
518 /* assume CPU is at P0... */
519 perf->state = 0;
520 return perf->states[0].core_frequency * 1000;
524 static void free_acpi_perf_data(void)
526 unsigned int i;
528 /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
529 for_each_possible_cpu(i)
530 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
531 ->shared_cpu_map);
532 free_percpu(acpi_perf_data);
535 static int cpufreq_boost_down_prep(unsigned int cpu)
538 * Clear the boost-disable bit on the CPU_DOWN path so that
539 * this cpu cannot block the remaining ones from boosting.
541 return boost_set_msr(1);
545 * acpi_cpufreq_early_init - initialize ACPI P-States library
547 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
548 * in order to determine correct frequency and voltage pairings. We can
549 * do _PDC and _PSD and find out the processor dependency for the
550 * actual init that will happen later...
552 static int __init acpi_cpufreq_early_init(void)
554 unsigned int i;
555 pr_debug("%s\n", __func__);
557 acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
558 if (!acpi_perf_data) {
559 pr_debug("Memory allocation error for acpi_perf_data.\n");
560 return -ENOMEM;
562 for_each_possible_cpu(i) {
563 if (!zalloc_cpumask_var_node(
564 &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
565 GFP_KERNEL, cpu_to_node(i))) {
567 /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
568 free_acpi_perf_data();
569 return -ENOMEM;
573 /* Do initialization in ACPI core */
574 acpi_processor_preregister_performance(acpi_perf_data);
575 return 0;
578 #ifdef CONFIG_SMP
580 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
581 * or do it in BIOS firmware and won't inform about it to OS. If not
582 * detected, this has a side effect of making CPU run at a different speed
583 * than OS intended it to run at. Detect it and handle it cleanly.
585 static int bios_with_sw_any_bug;
587 static int sw_any_bug_found(const struct dmi_system_id *d)
589 bios_with_sw_any_bug = 1;
590 return 0;
593 static const struct dmi_system_id sw_any_bug_dmi_table[] = {
595 .callback = sw_any_bug_found,
596 .ident = "Supermicro Server X6DLP",
597 .matches = {
598 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
599 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
600 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
606 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
608 /* Intel Xeon Processor 7100 Series Specification Update
609 * https://www.intel.com/Assets/PDF/specupdate/314554.pdf
610 * AL30: A Machine Check Exception (MCE) Occurring during an
611 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
612 * Both Processor Cores to Lock Up. */
613 if (c->x86_vendor == X86_VENDOR_INTEL) {
614 if ((c->x86 == 15) &&
615 (c->x86_model == 6) &&
616 (c->x86_stepping == 8)) {
617 pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
618 return -ENODEV;
621 return 0;
623 #endif
625 #ifdef CONFIG_ACPI_CPPC_LIB
626 static u64 get_max_boost_ratio(unsigned int cpu)
628 struct cppc_perf_caps perf_caps;
629 u64 highest_perf, nominal_perf;
630 int ret;
632 if (acpi_pstate_strict)
633 return 0;
635 ret = cppc_get_perf_caps(cpu, &perf_caps);
636 if (ret) {
637 pr_debug("CPU%d: Unable to get performance capabilities (%d)\n",
638 cpu, ret);
639 return 0;
642 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
643 ret = amd_get_boost_ratio_numerator(cpu, &highest_perf);
644 if (ret) {
645 pr_debug("CPU%d: Unable to get boost ratio numerator (%d)\n",
646 cpu, ret);
647 return 0;
649 } else {
650 highest_perf = perf_caps.highest_perf;
653 nominal_perf = perf_caps.nominal_perf;
655 if (!highest_perf || !nominal_perf) {
656 pr_debug("CPU%d: highest or nominal performance missing\n", cpu);
657 return 0;
660 if (highest_perf < nominal_perf) {
661 pr_debug("CPU%d: nominal performance above highest\n", cpu);
662 return 0;
665 return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf);
667 #else
668 static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; }
669 #endif
671 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
673 struct cpufreq_frequency_table *freq_table;
674 struct acpi_processor_performance *perf;
675 struct acpi_cpufreq_data *data;
676 unsigned int cpu = policy->cpu;
677 struct cpuinfo_x86 *c = &cpu_data(cpu);
678 unsigned int valid_states = 0;
679 unsigned int result = 0;
680 u64 max_boost_ratio;
681 unsigned int i;
682 #ifdef CONFIG_SMP
683 static int blacklisted;
684 #endif
686 pr_debug("%s\n", __func__);
688 #ifdef CONFIG_SMP
689 if (blacklisted)
690 return blacklisted;
691 blacklisted = acpi_cpufreq_blacklist(c);
692 if (blacklisted)
693 return blacklisted;
694 #endif
696 data = kzalloc(sizeof(*data), GFP_KERNEL);
697 if (!data)
698 return -ENOMEM;
700 if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
701 result = -ENOMEM;
702 goto err_free;
705 perf = per_cpu_ptr(acpi_perf_data, cpu);
706 data->acpi_perf_cpu = cpu;
707 policy->driver_data = data;
709 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
710 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
712 result = acpi_processor_register_performance(perf, cpu);
713 if (result)
714 goto err_free_mask;
716 policy->shared_type = perf->shared_type;
719 * Will let policy->cpus know about dependency only when software
720 * coordination is required.
722 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
723 policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
724 cpumask_copy(policy->cpus, perf->shared_cpu_map);
726 cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
728 #ifdef CONFIG_SMP
729 dmi_check_system(sw_any_bug_dmi_table);
730 if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
731 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
732 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
735 if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 &&
736 !acpi_pstate_strict) {
737 cpumask_clear(policy->cpus);
738 cpumask_set_cpu(cpu, policy->cpus);
739 cpumask_copy(data->freqdomain_cpus,
740 topology_sibling_cpumask(cpu));
741 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
742 pr_info_once("overriding BIOS provided _PSD data\n");
744 #endif
746 /* capability check */
747 if (perf->state_count <= 1) {
748 pr_debug("No P-States\n");
749 result = -ENODEV;
750 goto err_unreg;
753 if (perf->control_register.space_id != perf->status_register.space_id) {
754 result = -ENODEV;
755 goto err_unreg;
758 switch (perf->control_register.space_id) {
759 case ACPI_ADR_SPACE_SYSTEM_IO:
760 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
761 boot_cpu_data.x86 == 0xf) {
762 pr_debug("AMD K8 systems must use native drivers.\n");
763 result = -ENODEV;
764 goto err_unreg;
766 pr_debug("SYSTEM IO addr space\n");
767 data->cpu_feature = SYSTEM_IO_CAPABLE;
768 data->cpu_freq_read = cpu_freq_read_io;
769 data->cpu_freq_write = cpu_freq_write_io;
770 break;
771 case ACPI_ADR_SPACE_FIXED_HARDWARE:
772 pr_debug("HARDWARE addr space\n");
773 if (check_est_cpu(cpu)) {
774 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
775 data->cpu_freq_read = cpu_freq_read_intel;
776 data->cpu_freq_write = cpu_freq_write_intel;
777 break;
779 if (check_amd_hwpstate_cpu(cpu)) {
780 data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
781 data->cpu_freq_read = cpu_freq_read_amd;
782 data->cpu_freq_write = cpu_freq_write_amd;
783 break;
785 result = -ENODEV;
786 goto err_unreg;
787 default:
788 pr_debug("Unknown addr space %d\n",
789 (u32) (perf->control_register.space_id));
790 result = -ENODEV;
791 goto err_unreg;
794 freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),
795 GFP_KERNEL);
796 if (!freq_table) {
797 result = -ENOMEM;
798 goto err_unreg;
801 /* detect transition latency */
802 policy->cpuinfo.transition_latency = 0;
803 for (i = 0; i < perf->state_count; i++) {
804 if ((perf->states[i].transition_latency * 1000) >
805 policy->cpuinfo.transition_latency)
806 policy->cpuinfo.transition_latency =
807 perf->states[i].transition_latency * 1000;
810 /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
811 if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
812 policy->cpuinfo.transition_latency > 20 * 1000) {
813 policy->cpuinfo.transition_latency = 20 * 1000;
814 pr_info_once("P-state transition latency capped at 20 uS\n");
817 /* table init */
818 for (i = 0; i < perf->state_count; i++) {
819 if (i > 0 && perf->states[i].core_frequency >=
820 freq_table[valid_states-1].frequency / 1000)
821 continue;
823 freq_table[valid_states].driver_data = i;
824 freq_table[valid_states].frequency =
825 perf->states[i].core_frequency * 1000;
826 valid_states++;
828 freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
830 max_boost_ratio = get_max_boost_ratio(cpu);
831 if (max_boost_ratio) {
832 unsigned int freq = freq_table[0].frequency;
835 * Because the loop above sorts the freq_table entries in the
836 * descending order, freq is the maximum frequency in the table.
837 * Assume that it corresponds to the CPPC nominal frequency and
838 * use it to set cpuinfo.max_freq.
840 policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT;
841 } else {
843 * If the maximum "boost" frequency is unknown, ask the arch
844 * scale-invariance code to use the "nominal" performance for
845 * CPU utilization scaling so as to prevent the schedutil
846 * governor from selecting inadequate CPU frequencies.
848 arch_set_max_freq_ratio(true);
851 policy->freq_table = freq_table;
852 perf->state = 0;
854 switch (perf->control_register.space_id) {
855 case ACPI_ADR_SPACE_SYSTEM_IO:
857 * The core will not set policy->cur, because
858 * cpufreq_driver->get is NULL, so we need to set it here.
859 * However, we have to guess it, because the current speed is
860 * unknown and not detectable via IO ports.
862 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
863 break;
864 case ACPI_ADR_SPACE_FIXED_HARDWARE:
865 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
866 break;
867 default:
868 break;
871 /* notify BIOS that we exist */
872 acpi_processor_notify_smm(THIS_MODULE);
874 pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
875 for (i = 0; i < perf->state_count; i++)
876 pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
877 (i == perf->state ? '*' : ' '), i,
878 (u32) perf->states[i].core_frequency,
879 (u32) perf->states[i].power,
880 (u32) perf->states[i].transition_latency);
883 * the first call to ->target() should result in us actually
884 * writing something to the appropriate registers.
886 data->resume = 1;
888 policy->fast_switch_possible = !acpi_pstate_strict &&
889 !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
891 if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency)
892 pr_warn(FW_WARN "P-state 0 is not max freq\n");
894 if (acpi_cpufreq_driver.set_boost) {
895 set_boost(policy, acpi_cpufreq_driver.boost_enabled);
896 policy->boost_enabled = acpi_cpufreq_driver.boost_enabled;
899 return result;
901 err_unreg:
902 acpi_processor_unregister_performance(cpu);
903 err_free_mask:
904 free_cpumask_var(data->freqdomain_cpus);
905 err_free:
906 kfree(data);
907 policy->driver_data = NULL;
909 return result;
912 static void acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
914 struct acpi_cpufreq_data *data = policy->driver_data;
916 pr_debug("%s\n", __func__);
918 cpufreq_boost_down_prep(policy->cpu);
919 policy->fast_switch_possible = false;
920 policy->driver_data = NULL;
921 acpi_processor_unregister_performance(data->acpi_perf_cpu);
922 free_cpumask_var(data->freqdomain_cpus);
923 kfree(policy->freq_table);
924 kfree(data);
927 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
929 struct acpi_cpufreq_data *data = policy->driver_data;
931 pr_debug("%s\n", __func__);
933 data->resume = 1;
935 return 0;
938 static struct freq_attr *acpi_cpufreq_attr[] = {
939 &cpufreq_freq_attr_scaling_available_freqs,
940 &freqdomain_cpus,
941 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
942 &cpb,
943 #endif
944 NULL,
947 static struct cpufreq_driver acpi_cpufreq_driver = {
948 .verify = cpufreq_generic_frequency_table_verify,
949 .target_index = acpi_cpufreq_target,
950 .fast_switch = acpi_cpufreq_fast_switch,
951 .bios_limit = acpi_processor_get_bios_limit,
952 .init = acpi_cpufreq_cpu_init,
953 .exit = acpi_cpufreq_cpu_exit,
954 .resume = acpi_cpufreq_resume,
955 .name = "acpi-cpufreq",
956 .attr = acpi_cpufreq_attr,
959 static void __init acpi_cpufreq_boost_init(void)
961 if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {
962 pr_debug("Boost capabilities not present in the processor\n");
963 return;
966 acpi_cpufreq_driver.set_boost = set_boost;
967 acpi_cpufreq_driver.boost_enabled = boost_state(0);
970 static int __init acpi_cpufreq_probe(struct platform_device *pdev)
972 int ret;
974 if (acpi_disabled)
975 return -ENODEV;
977 /* don't keep reloading if cpufreq_driver exists */
978 if (cpufreq_get_current_driver())
979 return -ENODEV;
981 pr_debug("%s\n", __func__);
983 ret = acpi_cpufreq_early_init();
984 if (ret)
985 return ret;
987 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
988 /* this is a sysfs file with a strange name and an even stranger
989 * semantic - per CPU instantiation, but system global effect.
990 * Lets enable it only on AMD CPUs for compatibility reasons and
991 * only if configured. This is considered legacy code, which
992 * will probably be removed at some point in the future.
994 if (!check_amd_hwpstate_cpu(0)) {
995 struct freq_attr **attr;
997 pr_debug("CPB unsupported, do not expose it\n");
999 for (attr = acpi_cpufreq_attr; *attr; attr++)
1000 if (*attr == &cpb) {
1001 *attr = NULL;
1002 break;
1005 #endif
1006 acpi_cpufreq_boost_init();
1008 ret = cpufreq_register_driver(&acpi_cpufreq_driver);
1009 if (ret) {
1010 free_acpi_perf_data();
1012 return ret;
1015 static void acpi_cpufreq_remove(struct platform_device *pdev)
1017 pr_debug("%s\n", __func__);
1019 cpufreq_unregister_driver(&acpi_cpufreq_driver);
1021 free_acpi_perf_data();
1024 static struct platform_driver acpi_cpufreq_platdrv = {
1025 .driver = {
1026 .name = "acpi-cpufreq",
1028 .remove = acpi_cpufreq_remove,
1031 static int __init acpi_cpufreq_init(void)
1033 return platform_driver_probe(&acpi_cpufreq_platdrv, acpi_cpufreq_probe);
1036 static void __exit acpi_cpufreq_exit(void)
1038 platform_driver_unregister(&acpi_cpufreq_platdrv);
1041 module_param(acpi_pstate_strict, uint, 0644);
1042 MODULE_PARM_DESC(acpi_pstate_strict,
1043 "value 0 or non-zero. non-zero -> strict ACPI checks are "
1044 "performed during frequency changes.");
1046 late_initcall(acpi_cpufreq_init);
1047 module_exit(acpi_cpufreq_exit);
1049 MODULE_ALIAS("platform:acpi-cpufreq");