diff options
Diffstat (limited to 'include/linux/cpufreq.h')
| -rw-r--r-- | include/linux/cpufreq.h | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 718e8725d..4e81e08db 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -102,6 +102,17 @@ struct cpufreq_policy { */ struct rw_semaphore rwsem; + /* + * Fast switch flags: + * - fast_switch_possible should be set by the driver if it can + * guarantee that frequency can be changed on any CPU sharing the + * policy and that the change will affect all of the policy CPUs then. + * - fast_switch_enabled is to be set by governors that support fast + * freqnency switching with the help of cpufreq_enable_fast_switch(). + */ + bool fast_switch_possible; + bool fast_switch_enabled; + /* Synchronization for frequency transitions */ bool transition_ongoing; /* Tracks transition status */ spinlock_t transition_lock; @@ -156,6 +167,8 @@ 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); +void cpufreq_enable_fast_switch(struct cpufreq_policy *policy); +void cpufreq_disable_fast_switch(struct cpufreq_policy *policy); #else static inline unsigned int cpufreq_get(unsigned int cpu) { @@ -236,6 +249,8 @@ struct cpufreq_driver { unsigned int relation); /* Deprecated */ int (*target_index)(struct cpufreq_policy *policy, unsigned int index); + unsigned int (*fast_switch)(struct cpufreq_policy *policy, + unsigned int target_freq); /* * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION * unset. @@ -426,6 +441,20 @@ static inline unsigned long cpufreq_scale(unsigned long old, u_int div, #define CPUFREQ_POLICY_POWERSAVE (1) #define CPUFREQ_POLICY_PERFORMANCE (2) +/* + * The polling frequency depends on the capability of the processor. Default + * polling frequency is 1000 times the transition latency of the processor. The + * ondemand governor will work on any processor with transition latency <= 10ms, + * using appropriate sampling rate. + * + * For CPUs with transition latency > 10ms (mostly drivers with CPUFREQ_ETERNAL) + * the ondemand governor will not work. All times here are in us (microseconds). + */ +#define MIN_SAMPLING_RATE_RATIO (2) +#define LATENCY_MULTIPLIER (1000) +#define MIN_LATENCY_MULTIPLIER (20) +#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000) + /* Governor Events */ #define CPUFREQ_GOV_START 1 #define CPUFREQ_GOV_STOP 2 @@ -450,6 +479,8 @@ struct cpufreq_governor { }; /* Pass a target to the cpufreq driver */ +unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, + unsigned int target_freq); int cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); @@ -462,6 +493,29 @@ void cpufreq_unregister_governor(struct cpufreq_governor *governor); struct cpufreq_governor *cpufreq_default_governor(void); struct cpufreq_governor *cpufreq_fallback_governor(void); +/* Governor attribute set */ +struct gov_attr_set { + struct kobject kobj; + struct list_head policy_list; + struct mutex update_lock; + int usage_count; +}; + +/* sysfs ops for cpufreq governors */ +extern const struct sysfs_ops governor_sysfs_ops; + +void gov_attr_set_init(struct gov_attr_set *attr_set, struct list_head *list_node); +void gov_attr_set_get(struct gov_attr_set *attr_set, struct list_head *list_node); +unsigned int gov_attr_set_put(struct gov_attr_set *attr_set, struct list_head *list_node); + +/* Governor sysfs attribute */ +struct governor_attr { + struct attribute attr; + ssize_t (*show)(struct gov_attr_set *attr_set, char *buf); + ssize_t (*store)(struct gov_attr_set *attr_set, const char *buf, + size_t count); +}; + /********************************************************************* * FREQUENCY TABLE HELPERS * *********************************************************************/ |