diff options
Diffstat (limited to 'include/linux/cpufreq.h')
| -rw-r--r-- | include/linux/cpufreq.h | 341 |
1 files changed, 325 insertions, 16 deletions
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 718e8725de8a..631ba33bbe9f 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -36,6 +36,12 @@ struct cpufreq_governor; +enum cpufreq_table_sorting { + CPUFREQ_TABLE_UNSORTED, + CPUFREQ_TABLE_SORTED_ASCENDING, + CPUFREQ_TABLE_SORTED_DESCENDING +}; + struct cpufreq_freqs { unsigned int cpu; /* cpu nr */ unsigned int old; @@ -87,6 +93,7 @@ struct cpufreq_policy { struct cpufreq_user_policy user_policy; struct cpufreq_frequency_table *freq_table; + enum cpufreq_table_sorting freq_table_sorted; struct list_head policy_list; struct kobject kobj; @@ -102,6 +109,21 @@ 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; + + /* Cached frequency lookup from cpufreq_driver_resolve_freq. */ + unsigned int cached_target_freq; + int cached_resolved_idx; + /* Synchronization for frequency transitions */ bool transition_ongoing; /* Tracks transition status */ spinlock_t transition_lock; @@ -156,6 +178,8 @@ 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) { @@ -172,6 +196,18 @@ static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) static inline void disable_cpufreq(void) { } #endif +#ifdef CONFIG_CPU_FREQ_STAT +void cpufreq_stats_create_table(struct cpufreq_policy *policy); +void cpufreq_stats_free_table(struct cpufreq_policy *policy); +void cpufreq_stats_record_transition(struct cpufreq_policy *policy, + unsigned int new_freq); +#else +static inline void cpufreq_stats_create_table(struct cpufreq_policy *policy) { } +static inline void cpufreq_stats_free_table(struct cpufreq_policy *policy) { } +static inline void cpufreq_stats_record_transition(struct cpufreq_policy *policy, + unsigned int new_freq) { } +#endif /* CONFIG_CPU_FREQ_STAT */ + /********************************************************************* * CPUFREQ DRIVER INTERFACE * *********************************************************************/ @@ -236,6 +272,18 @@ 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); + + /* + * Caches and returns the lowest driver-supported frequency greater than + * or equal to the target frequency, subject to any driver limitations. + * Does not set the frequency. Only to be implemented for drivers with + * target(). + */ + unsigned int (*resolve_freq)(struct cpufreq_policy *policy, + unsigned int target_freq); + /* * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION * unset. @@ -426,18 +474,27 @@ static inline unsigned long cpufreq_scale(unsigned long old, u_int div, #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 +/* + * 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) struct cpufreq_governor { char name[CPUFREQ_NAME_LEN]; - int initialized; - int (*governor) (struct cpufreq_policy *policy, - unsigned int event); + int (*init)(struct cpufreq_policy *policy); + void (*exit)(struct cpufreq_policy *policy); + int (*start)(struct cpufreq_policy *policy); + void (*stop)(struct cpufreq_policy *policy); + void (*limits)(struct cpufreq_policy *policy); ssize_t (*show_setspeed) (struct cpufreq_policy *policy, char *buf); int (*store_setspeed) (struct cpufreq_policy *policy, @@ -450,18 +507,53 @@ 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); int __cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); +unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, + unsigned int target_freq); int cpufreq_register_governor(struct cpufreq_governor *governor); void cpufreq_unregister_governor(struct cpufreq_governor *governor); struct cpufreq_governor *cpufreq_default_governor(void); struct cpufreq_governor *cpufreq_fallback_governor(void); +static inline void cpufreq_policy_apply_limits(struct cpufreq_policy *policy) +{ + if (policy->max < policy->cur) + __cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H); + else if (policy->min > policy->cur) + __cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L); +} + +/* 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 * *********************************************************************/ @@ -528,11 +620,9 @@ 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); +int cpufreq_table_index_unsorted(struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation); int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, unsigned int freq); @@ -543,6 +633,227 @@ int cpufreq_boost_trigger_state(int state); int cpufreq_boost_enabled(void); int cpufreq_enable_boost_support(void); bool policy_has_boost_freq(struct cpufreq_policy *policy); + +/* Find lowest freq at or above target in a table in ascending order */ +static inline int cpufreq_table_find_index_al(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq >= target_freq) + return i; + + best = i; + } + + return best; +} + +/* Find lowest freq at or above target in a table in descending order */ +static inline int cpufreq_table_find_index_dl(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq == target_freq) + return i; + + if (freq > target_freq) { + best = i; + continue; + } + + /* No freq found above target_freq */ + if (best == -1) + return i; + + return best; + } + + return best; +} + +/* Works only on sorted freq-tables */ +static inline int cpufreq_table_find_index_l(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + target_freq = clamp_val(target_freq, policy->min, policy->max); + + if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING) + return cpufreq_table_find_index_al(policy, target_freq); + else + return cpufreq_table_find_index_dl(policy, target_freq); +} + +/* Find highest freq at or below target in a table in ascending order */ +static inline int cpufreq_table_find_index_ah(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq == target_freq) + return i; + + if (freq < target_freq) { + best = i; + continue; + } + + /* No freq found below target_freq */ + if (best == -1) + return i; + + return best; + } + + return best; +} + +/* Find highest freq at or below target in a table in descending order */ +static inline int cpufreq_table_find_index_dh(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq <= target_freq) + return i; + + best = i; + } + + return best; +} + +/* Works only on sorted freq-tables */ +static inline int cpufreq_table_find_index_h(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + target_freq = clamp_val(target_freq, policy->min, policy->max); + + if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING) + return cpufreq_table_find_index_ah(policy, target_freq); + else + return cpufreq_table_find_index_dh(policy, target_freq); +} + +/* Find closest freq to target in a table in ascending order */ +static inline int cpufreq_table_find_index_ac(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq == target_freq) + return i; + + if (freq < target_freq) { + best = i; + continue; + } + + /* No freq found below target_freq */ + if (best == -1) + return i; + + /* Choose the closest freq */ + if (target_freq - table[best].frequency > freq - target_freq) + return i; + + return best; + } + + return best; +} + +/* Find closest freq to target in a table in descending order */ +static inline int cpufreq_table_find_index_dc(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + struct cpufreq_frequency_table *table = policy->freq_table; + unsigned int freq; + int i, best = -1; + + for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { + freq = table[i].frequency; + + if (freq == target_freq) + return i; + + if (freq > target_freq) { + best = i; + continue; + } + + /* No freq found above target_freq */ + if (best == -1) + return i; + + /* Choose the closest freq */ + if (table[best].frequency - target_freq > target_freq - freq) + return i; + + return best; + } + + return best; +} + +/* Works only on sorted freq-tables */ +static inline int cpufreq_table_find_index_c(struct cpufreq_policy *policy, + unsigned int target_freq) +{ + target_freq = clamp_val(target_freq, policy->min, policy->max); + + if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING) + return cpufreq_table_find_index_ac(policy, target_freq); + else + return cpufreq_table_find_index_dc(policy, target_freq); +} + +static inline int cpufreq_frequency_table_target(struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation) +{ + if (unlikely(policy->freq_table_sorted == CPUFREQ_TABLE_UNSORTED)) + return cpufreq_table_index_unsorted(policy, target_freq, + relation); + + switch (relation) { + case CPUFREQ_RELATION_L: + return cpufreq_table_find_index_l(policy, target_freq); + case CPUFREQ_RELATION_H: + return cpufreq_table_find_index_h(policy, target_freq); + case CPUFREQ_RELATION_C: + return cpufreq_table_find_index_c(policy, target_freq); + default: + pr_err("%s: Invalid relation: %d\n", __func__, relation); + return -EINVAL; + } +} #else static inline int cpufreq_boost_trigger_state(int state) { @@ -563,8 +874,6 @@ static inline bool policy_has_boost_freq(struct cpufreq_policy *policy) return false; } #endif -/* 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; |