/* * linux/include/linux/cpufreq.h * * Copyright (C) 2001 Russell King * (C) 2002 - 2003 Dominik Brodowski * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #ifndef _LINUX_CPUFREQ_H #define _LINUX_CPUFREQ_H #include #include #include #include #include /********************************************************************* * CPUFREQ INTERFACE * *********************************************************************/ /* * Frequency values here are CPU kHz * * Maximum transition latency is in nanoseconds - if it's unknown, * CPUFREQ_ETERNAL shall be used. */ #define CPUFREQ_ETERNAL (-1) #define CPUFREQ_NAME_LEN 16 /* Print length for names. Extra 1 space for accomodating '\n' in prints */ #define CPUFREQ_NAME_PLEN (CPUFREQ_NAME_LEN + 1) struct cpufreq_governor; struct cpufreq_freqs { unsigned int cpu; /* cpu nr */ unsigned int old; unsigned int new; u8 flags; /* flags of cpufreq_driver, see below. */ }; struct cpufreq_cpuinfo { unsigned int max_freq; unsigned int min_freq; /* in 10^(-9) s = nanoseconds */ unsigned int transition_latency; }; struct cpufreq_real_policy { unsigned int min; /* in kHz */ unsigned int max; /* in kHz */ unsigned int policy; /* see above */ struct cpufreq_governor *governor; /* see below */ }; struct cpufreq_policy { /* CPUs sharing clock, require sw coordination */ cpumask_var_t cpus; /* Online CPUs only */ cpumask_var_t related_cpus; /* Online + Offline CPUs */ unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs should set cpufreq */ unsigned int cpu; /* cpu nr of CPU managing this policy */ unsigned int last_cpu; /* cpu nr of previous CPU that managed * this policy */ struct cpufreq_cpuinfo cpuinfo;/* see above */ unsigned int min; /* in kHz */ unsigned int max; /* in kHz */ unsigned int cur; /* in kHz, only needed if cpufreq * governors are used */ unsigned int policy; /* see above */ struct cpufreq_governor *governor; /* see below */ void *governor_data; bool governor_enabled; /* governor start/stop flag */ struct work_struct update; /* if update_policy() needs to be * called, but you're in IRQ context */ struct cpufreq_real_policy user_policy; struct list_head policy_list; struct kobject kobj; struct completion kobj_unregister; /* * The rules for this semaphore: * - Any routine that wants to read from the policy structure will * do a down_read on this semaphore. * - Any routine that will write to the policy structure and/or may take away * the policy altogether (eg. CPU hotplug), will hold this lock in write * mode before doing so. * * Additional rules: * - Lock should not be held across * __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT); */ struct rw_semaphore rwsem; }; /* Only for ACPI */ #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */ #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ #ifdef CONFIG_CPU_FREQ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); void cpufreq_cpu_put(struct cpufreq_policy *policy); #else static inline struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) { return NULL; } static inline void cpufreq_cpu_put(struct cpufreq_policy *policy) { } #endif static inline bool policy_is_shared(struct cpufreq_policy *policy) { return cpumask_weight(policy->cpus) > 1; } /* /sys/devices/system/cpu/cpufreq: entry point for global variables */ extern struct kobject *cpufreq_global_kobject; int cpufreq_get_global_kobject(void); void cpufreq_put_global_kobject(void); int cpufreq_sysfs_create_file(const struct attribute *attr); void cpufreq_sysfs_remove_file(const struct attribute *attr); #ifdef CONFIG_CPU_FREQ unsigned int cpufreq_get(unsigned int cpu); unsigned int cpufreq_quick_get(unsigned int cpu); unsigned int cpufreq_quick_get_max(unsigned int cpu); void disable_cpufreq(void); u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy); int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu); int cpufreq_update_policy(unsigned int cpu); bool have_governor_per_policy(void); struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy); #else static inline unsigned int cpufreq_get(unsigned int cpu) { return 0; } static inline unsigned int cpufreq_quick_get(unsigned int cpu) { return 0; } static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) { return 0; } static inline void disable_cpufreq(void) { } #endif /********************************************************************* * CPUFREQ DRIVER INTERFACE * *********************************************************************/ #define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */ #define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */ struct freq_attr { struct attribute attr; ssize_t (*show)(struct cpufreq_policy *, char *); ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); }; #define cpufreq_freq_attr_ro(_name) \ static struct freq_attr _name = \ __ATTR(_name, 0444, show_##_name, NULL) #define cpufreq_freq_attr_ro_perm(_name, _perm) \ static struct freq_attr _name = \ __ATTR(_name, _perm, show_##_name, NULL) #define cpufreq_freq_attr_rw(_name) \ static struct freq_attr _name = \ __ATTR(_name, 0644, show_##_name, store_##_name) struct global_attr { struct attribute attr; ssize_t (*show)(struct kobject *kobj, struct attribute *attr, char *buf); ssize_t (*store)(struct kobject *a, struct attribute *b, const char *c, size_t count); }; #define define_one_global_ro(_name) \ static struct global_attr _name = \ __ATTR(_name, 0444, show_##_name, NULL) #define define_one_global_rw(_name) \ static struct global_attr _name = \ __ATTR(_name, 0644, show_##_name, store_##_name) struct cpufreq_driver { char name[CPUFREQ_NAME_LEN]; u8 flags; /* needed by all drivers */ int (*init) (struct cpufreq_policy *policy); int (*verify) (struct cpufreq_policy *policy); /* define one out of two */ int (*setpolicy) (struct cpufreq_policy *policy); int (*target) (struct cpufreq_policy *policy, /* Deprecated */ unsigned int target_freq, unsigned int relation); int (*target_index) (struct cpufreq_policy *policy, unsigned int index); /* should be defined, if possible */ unsigned int (*get) (unsigned int cpu); /* optional */ int (*bios_limit) (int cpu, unsigned int *limit); int (*exit) (struct cpufreq_policy *policy); int (*suspend) (struct cpufreq_policy *policy); int (*resume) (struct cpufreq_policy *policy); struct freq_attr **attr; }; /* flags */ #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if all ->init() calls failed */ #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other kernel "constants" aren't affected by frequency transitions */ #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume speed mismatches */ /* * This should be set by platforms having multiple clock-domains, i.e. * supporting multiple policies. With this sysfs directories of governor would * be created in cpu/cpu/cpufreq/ directory and so they can use the same * governor with different tunables for different clusters. */ #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3) /* * Driver will do POSTCHANGE notifications from outside of their ->target() * routine and so must set cpufreq_driver->flags with this flag, so that core * can handle them specially. */ #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4) int cpufreq_register_driver(struct cpufreq_driver *driver_data); int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); const char *cpufreq_get_current_driver(void); static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, unsigned int min, unsigned int max) { if (policy->min < min) policy->min = min; if (policy->max < min) policy->max = min; if (policy->min > max) policy->min = max; if (policy->max > max) policy->max = max; if (policy->min > policy->max) policy->min = policy->max; return; } static inline void cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy) { cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq); } /********************************************************************* * CPUFREQ NOTIFIER INTERFACE * *********************************************************************/ #define CPUFREQ_TRANSITION_NOTIFIER (0) #define CPUFREQ_POLICY_NOTIFIER (1) /* Transition notifiers */ #define CPUFREQ_PRECHANGE (0) #define CPUFREQ_POSTCHANGE (1) #define CPUFREQ_RESUMECHANGE (8) #define CPUFREQ_SUSPENDCHANGE (9) /* Policy Notifiers */ #define CPUFREQ_ADJUST (0) #define CPUFREQ_INCOMPATIBLE (1) #define CPUFREQ_NOTIFY (2) #define CPUFREQ_START (3) #define CPUFREQ_UPDATE_POLICY_CPU (4) #ifdef CONFIG_CPU_FREQ int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); void cpufreq_notify_transition(struct cpufreq_policy *policy, struct cpufreq_freqs *freqs, unsigned int state); void cpufreq_notify_post_transition(struct cpufreq_policy *policy, struct cpufreq_freqs *freqs, int transition_failed); #else /* CONFIG_CPU_FREQ */ static inline int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) { return 0; } static inline int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) { return 0; } #endif /* !CONFIG_CPU_FREQ */ /** * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch * safe) * @old: old value * @div: divisor * @mult: multiplier * * * new = old * mult / div */ static inline unsigned long cpufreq_scale(unsigned long old, u_int div, u_int mult) { #if BITS_PER_LONG == 32 u64 result = ((u64) old) * ((u64) mult); do_div(result, div); return (unsigned long) result; #elif BITS_PER_LONG == 64 unsigned long result = old * ((u64) mult); result /= div; return result; #endif } /********************************************************************* * CPUFREQ GOVERNORS * *********************************************************************/ /* * If (cpufreq_driver->target) exists, the ->governor decides what frequency * within the limits is used. If (cpufreq_driver->setpolicy> exists, these * two generic policies are available: */ #define CPUFREQ_POLICY_POWERSAVE (1) #define CPUFREQ_POLICY_PERFORMANCE (2) /* Governor Events */ #define CPUFREQ_GOV_START 1 #define CPUFREQ_GOV_STOP 2 #define CPUFREQ_GOV_LIMITS 3 #define CPUFREQ_GOV_POLICY_INIT 4 #define CPUFREQ_GOV_POLICY_EXIT 5 struct cpufreq_governor { char name[CPUFREQ_NAME_LEN]; int initialized; int (*governor) (struct cpufreq_policy *policy, unsigned int event); ssize_t (*show_setspeed) (struct cpufreq_policy *policy, char *buf); int (*store_setspeed) (struct cpufreq_policy *policy, unsigned int freq); unsigned int max_transition_latency; /* HW must be able to switch to next freq faster than this value in nano secs or we will fallback to performance governor */ struct list_head governor_list; struct module *owner; }; /* Pass a target to the cpufreq driver */ int cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); int __cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); int cpufreq_register_governor(struct cpufreq_governor *governor); void cpufreq_unregister_governor(struct cpufreq_governor *governor); /* CPUFREQ DEFAULT GOVERNOR */ /* * Performance governor is fallback governor if any other gov failed to auto * load due latency restrictions */ #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE extern struct cpufreq_governor cpufreq_gov_performance; #endif #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance) #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE) extern struct cpufreq_governor cpufreq_gov_powersave; #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave) #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE) extern struct cpufreq_governor cpufreq_gov_userspace; #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace) #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND) extern struct cpufreq_governor cpufreq_gov_ondemand; #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand) #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE) extern struct cpufreq_governor cpufreq_gov_conservative; #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative) #endif /********************************************************************* * FREQUENCY TABLE HELPERS * *********************************************************************/ #define CPUFREQ_ENTRY_INVALID ~0 #define CPUFREQ_TABLE_END ~1 struct cpufreq_frequency_table { unsigned int driver_data; /* driver specific data, not used by core */ unsigned int frequency; /* kHz - doesn't need to be in ascending * order */ }; int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table); int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table); int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy); int cpufreq_frequency_table_target(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table, unsigned int target_freq, unsigned int relation, unsigned int *index); void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy); ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf); /* the following funtion is for cpufreq core use only */ struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); /* the following are really really optional */ extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; extern struct freq_attr *cpufreq_generic_attr[]; void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table, unsigned int cpu); void cpufreq_frequency_table_put_attr(unsigned int cpu); int cpufreq_table_validate_and_show(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table); int cpufreq_generic_init(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table, unsigned int transition_latency); static inline int cpufreq_generic_exit(struct cpufreq_policy *policy) { cpufreq_frequency_table_put_attr(policy->cpu); return 0; } #endif /* _LINUX_CPUFREQ_H */