diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 222c3e01397c..57b93e3d8f29 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -267,4 +267,48 @@ static inline s32 dev_pm_qos_raw_resume_latency(struct device *dev) } #endif +#define FREQ_QOS_MIN_DEFAULT_VALUE 0 +#define FREQ_QOS_MAX_DEFAULT_VALUE (-1) + +enum freq_qos_req_type { + FREQ_QOS_MIN = 1, + FREQ_QOS_MAX, +}; + +struct freq_constraints { + struct pm_qos_constraints min_freq; + struct blocking_notifier_head min_freq_notifiers; + struct pm_qos_constraints max_freq; + struct blocking_notifier_head max_freq_notifiers; +}; + +struct freq_qos_request { + enum freq_qos_req_type type; + struct plist_node pnode; + struct freq_constraints *qos; +}; + +static inline int freq_qos_request_active(struct freq_qos_request *req) +{ + return !IS_ERR_OR_NULL(req->qos); +} + +void freq_constraints_init(struct freq_constraints *qos); + +s32 freq_qos_read_value(struct freq_constraints *qos, + enum freq_qos_req_type type); + +int freq_qos_add_request(struct freq_constraints *qos, + struct freq_qos_request *req, + enum freq_qos_req_type type, s32 value); +int freq_qos_update_request(struct freq_qos_request *req, s32 new_value); +int freq_qos_remove_request(struct freq_qos_request *req); + +int freq_qos_add_notifier(struct freq_constraints *qos, + enum freq_qos_req_type type, + struct notifier_block *notifier); +int freq_qos_remove_notifier(struct freq_constraints *qos, + enum freq_qos_req_type type, + struct notifier_block *notifier); + #endif diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 9568a2fe7c11..04e83fdfbe80 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -650,3 +650,243 @@ static int __init pm_qos_power_init(void) } late_initcall(pm_qos_power_init); + +/* Definitions related to the frequency QoS below. */ + +/** + * freq_constraints_init - Initialize frequency QoS constraints. + * @qos: Frequency QoS constraints to initialize. + */ +void freq_constraints_init(struct freq_constraints *qos) +{ + struct pm_qos_constraints *c; + + c = &qos->min_freq; + plist_head_init(&c->list); + c->target_value = FREQ_QOS_MIN_DEFAULT_VALUE; + c->default_value = FREQ_QOS_MIN_DEFAULT_VALUE; + c->no_constraint_value = FREQ_QOS_MIN_DEFAULT_VALUE; + c->type = PM_QOS_MAX; + c->notifiers = &qos->min_freq_notifiers; + BLOCKING_INIT_NOTIFIER_HEAD(c->notifiers); + + c = &qos->max_freq; + plist_head_init(&c->list); + c->target_value = FREQ_QOS_MAX_DEFAULT_VALUE; + c->default_value = FREQ_QOS_MAX_DEFAULT_VALUE; + c->no_constraint_value = FREQ_QOS_MAX_DEFAULT_VALUE; + c->type = PM_QOS_MIN; + c->notifiers = &qos->max_freq_notifiers; + BLOCKING_INIT_NOTIFIER_HEAD(c->notifiers); +} + +/** + * freq_qos_read_value - Get frequency QoS constraint for a given list. + * @qos: Constraints to evaluate. + * @type: QoS request type. + */ +s32 freq_qos_read_value(struct freq_constraints *qos, + enum freq_qos_req_type type) +{ + s32 ret; + + switch (type) { + case FREQ_QOS_MIN: + ret = IS_ERR_OR_NULL(qos) ? + FREQ_QOS_MIN_DEFAULT_VALUE : + pm_qos_read_value(&qos->min_freq); + break; + case FREQ_QOS_MAX: + ret = IS_ERR_OR_NULL(qos) ? + FREQ_QOS_MAX_DEFAULT_VALUE : + pm_qos_read_value(&qos->max_freq); + break; + default: + WARN_ON(1); + ret = 0; + } + + return ret; +} + +/** + * freq_qos_apply - Add/modify/remove frequency QoS request. + * @req: Constraint request to apply. + * @action: Action to perform (add/update/remove). + * @value: Value to assign to the QoS request. + */ +static int freq_qos_apply(struct freq_qos_request *req, + enum pm_qos_req_action action, s32 value) +{ + int ret; + + switch(req->type) { + case FREQ_QOS_MIN: + ret = pm_qos_update_target(&req->qos->min_freq, &req->pnode, + action, value); + break; + case FREQ_QOS_MAX: + ret = pm_qos_update_target(&req->qos->max_freq, &req->pnode, + action, value); + break; + default: + ret = -EINVAL; + } + + return ret; +} + +/** + * freq_qos_add_request - Insert new frequency QoS request into a given list. + * @qos: Constraints to update. + * @req: Preallocated request object. + * @type: Request type. + * @value: Request value. + * + * Insert a new entry into the @qos list of requests, recompute the effective + * QoS constraint value for that list and initialize the @req object. The + * caller needs to save that object for later use in updates and removal. + * + * Return 1 if the effective constraint value has changed, 0 if the effective + * constraint value has not changed, or a negative error code on failures. + */ +int freq_qos_add_request(struct freq_constraints *qos, + struct freq_qos_request *req, + enum freq_qos_req_type type, s32 value) +{ + int ret; + + if (IS_ERR_OR_NULL(qos) || !req) + return -EINVAL; + + if (WARN(freq_qos_request_active(req), + "%s() called for active request\n", __func__)) + return -EINVAL; + + req->qos = qos; + req->type = type; + ret = freq_qos_apply(req, PM_QOS_ADD_REQ, value); + if (ret < 0) { + req->qos = NULL; + req->type = 0; + } + + return ret; +} +EXPORT_SYMBOL_GPL(freq_qos_add_request); + +/** + * freq_qos_update_request - Modify existing frequency QoS request. + * @req: Request to modify. + * @new_value: New request value. + * + * Update an existing frequency QoS request along with the effective constraint + * value for the list of requests it belongs to. + * + * Return 1 if the effective constraint value has changed, 0 if the effective + * constraint value has not changed, or a negative error code on failures. + */ +int freq_qos_update_request(struct freq_qos_request *req, s32 new_value) +{ + if (!req) + return -EINVAL; + + if (WARN(!freq_qos_request_active(req), + "%s() called for unknown object\n", __func__)) + return -EINVAL; + + if (req->pnode.prio == new_value) + return 0; + + return freq_qos_apply(req, PM_QOS_UPDATE_REQ, new_value); +} +EXPORT_SYMBOL_GPL(freq_qos_update_request); + +/** + * freq_qos_remove_request - Remove frequency QoS request from its list. + * @req: Request to remove. + * + * Remove the given frequency QoS request from the list of constraints it + * belongs to and recompute the effective constraint value for that list. + * + * Return 1 if the effective constraint value has changed, 0 if the effective + * constraint value has not changed, or a negative error code on failures. + */ +int freq_qos_remove_request(struct freq_qos_request *req) +{ + if (!req) + return -EINVAL; + + if (WARN(!freq_qos_request_active(req), + "%s() called for unknown object\n", __func__)) + return -EINVAL; + + return freq_qos_apply(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); +} +EXPORT_SYMBOL_GPL(freq_qos_remove_request); + +/** + * freq_qos_add_notifier - Add frequency QoS change notifier. + * @qos: List of requests to add the notifier to. + * @type: Request type. + * @notifier: Notifier block to add. + */ +int freq_qos_add_notifier(struct freq_constraints *qos, + enum freq_qos_req_type type, + struct notifier_block *notifier) +{ + int ret; + + if (IS_ERR_OR_NULL(qos) || !notifier) + return -EINVAL; + + switch (type) { + case FREQ_QOS_MIN: + ret = blocking_notifier_chain_register(qos->min_freq.notifiers, + notifier); + break; + case FREQ_QOS_MAX: + ret = blocking_notifier_chain_register(qos->max_freq.notifiers, + notifier); + break; + default: + WARN_ON(1); + ret = -EINVAL; + } + + return ret; +} +EXPORT_SYMBOL_GPL(freq_qos_add_notifier); + +/** + * freq_qos_remove_notifier - Remove frequency QoS change notifier. + * @qos: List of requests to remove the notifier from. + * @type: Request type. + * @notifier: Notifier block to remove. + */ +int freq_qos_remove_notifier(struct freq_constraints *qos, + enum freq_qos_req_type type, + struct notifier_block *notifier) +{ + int ret; + + if (IS_ERR_OR_NULL(qos) || !notifier) + return -EINVAL; + + switch (type) { + case FREQ_QOS_MIN: + ret = blocking_notifier_chain_unregister(qos->min_freq.notifiers, + notifier); + break; + case FREQ_QOS_MAX: + ret = blocking_notifier_chain_unregister(qos->max_freq.notifiers, + notifier); + break; + default: + WARN_ON(1); + ret = -EINVAL; + } + + return ret; +} +EXPORT_SYMBOL_GPL(freq_qos_remove_notifier);