1 // SPDX-License-Identifier: GPL-2.0-only
15  * or through a built-in notification mechanism.
18  * global CPU latency QoS requests and frequency QoS requests are provided.
50  * pm_qos_read_value - Return the current effective constraint value.
55 	return READ_ONCE(c->target_value);  in pm_qos_read_value()
60 	if (plist_head_empty(&c->list))  in pm_qos_get_value()
61 		return c->no_constraint_value;  in pm_qos_get_value()
63 	switch (c->type) {  in pm_qos_get_value()
65 		return plist_first(&c->list)->prio;  in pm_qos_get_value()
68 		return plist_last(&c->list)->prio;  in pm_qos_get_value()
78 	WRITE_ONCE(c->target_value, value);  in pm_qos_set_value()
82  * pm_qos_update_target - Update a list of PM QoS constraint requests.
84  * @node: Target list entry.
86  * @value: New request value for the target list entry.
89  * @action involving the @node list entry and @value on it.
108 		new_value = c->default_value;  in pm_qos_update_target()
114 		plist_del(node, &c->list);  in pm_qos_update_target()
121 		plist_del(node, &c->list);  in pm_qos_update_target()
125 		plist_add(node, &c->list);  in pm_qos_update_target()
142 	if (c->notifiers)  in pm_qos_update_target()
143 		blocking_notifier_call_chain(c->notifiers, curr_value, NULL);  in pm_qos_update_target()
149  * pm_qos_flags_remove_req - Remove device PM QoS flags request.
158 	list_del(&req->node);  in pm_qos_flags_remove_req()
159 	list_for_each_entry(req, &pqf->list, node)  in pm_qos_flags_remove_req()
160 		val |= req->flags;  in pm_qos_flags_remove_req()
162 	pqf->effective_flags = val;  in pm_qos_flags_remove_req()
166  * pm_qos_update_flags - Update a set of PM QoS flags.
183 	prev_value = list_empty(&pqf->list) ? 0 : pqf->effective_flags;  in pm_qos_update_flags()
193 		req->flags = val;  in pm_qos_update_flags()
194 		INIT_LIST_HEAD(&req->node);  in pm_qos_update_flags()
195 		list_add_tail(&req->node, &pqf->list);  in pm_qos_update_flags()
196 		pqf->effective_flags |= val;  in pm_qos_update_flags()
203 	curr_value = list_empty(&pqf->list) ? 0 : pqf->effective_flags;  in pm_qos_update_flags()
213 /* Definitions related to the CPU latency QoS. */
224  * cpu_latency_qos_limit - Return current system-wide CPU latency QoS limit.
232  * cpu_latency_qos_request_active - Check the given PM QoS request.
235  * Return: 'true' if @req has been added to the CPU latency QoS list, 'false'
240 	return req->qos == &cpu_latency_constraints;  in cpu_latency_qos_request_active()
247 	int ret = pm_qos_update_target(req->qos, &req->node, action, value);  in cpu_latency_qos_apply()
253  * cpu_latency_qos_add_request - Add new CPU latency QoS request.
258  * a new entry to the CPU latency QoS list and recompute the effective QoS
276 	req->qos = &cpu_latency_constraints;  in cpu_latency_qos_add_request()
282  * cpu_latency_qos_update_request - Modify existing CPU latency QoS request.
287  * latency QoS list along with updating the effective constraint value for that
302 	if (new_value == req->node.prio)  in cpu_latency_qos_update_request()
310  * cpu_latency_qos_remove_request - Remove existing CPU latency QoS request.
313  * Remove the CPU latency QoS request represented by @req from the CPU latency
333 /* User space interface to the CPU latency QoS via misc device. */
341 		return -ENOMEM;  in cpu_latency_qos_open()
344 	filp->private_data = req;  in cpu_latency_qos_open()
351 	struct pm_qos_request *req = filp->private_data;  in cpu_latency_qos_release()
353 	filp->private_data = NULL;  in cpu_latency_qos_release()
364 	struct pm_qos_request *req = filp->private_data;  in cpu_latency_qos_read()
369 		return -EINVAL;  in cpu_latency_qos_read()
385 			return -EFAULT;  in cpu_latency_qos_write()
394 	cpu_latency_qos_update_request(filp->private_data, value);  in cpu_latency_qos_write()
430  * freq_constraints_init - Initialize frequency QoS constraints.
437 	c = &qos->min_freq;  in freq_constraints_init()
438 	plist_head_init(&c->list);  in freq_constraints_init()
439 	c->target_value = FREQ_QOS_MIN_DEFAULT_VALUE;  in freq_constraints_init()
440 	c->default_value = FREQ_QOS_MIN_DEFAULT_VALUE;  in freq_constraints_init()
441 	c->no_constraint_value = FREQ_QOS_MIN_DEFAULT_VALUE;  in freq_constraints_init()
442 	c->type = PM_QOS_MAX;  in freq_constraints_init()
443 	c->notifiers = &qos->min_freq_notifiers;  in freq_constraints_init()
444 	BLOCKING_INIT_NOTIFIER_HEAD(c->notifiers);  in freq_constraints_init()
446 	c = &qos->max_freq;  in freq_constraints_init()
447 	plist_head_init(&c->list);  in freq_constraints_init()
448 	c->target_value = FREQ_QOS_MAX_DEFAULT_VALUE;  in freq_constraints_init()
449 	c->default_value = FREQ_QOS_MAX_DEFAULT_VALUE;  in freq_constraints_init()
450 	c->no_constraint_value = FREQ_QOS_MAX_DEFAULT_VALUE;  in freq_constraints_init()
451 	c->type = PM_QOS_MIN;  in freq_constraints_init()
452 	c->notifiers = &qos->max_freq_notifiers;  in freq_constraints_init()
453 	BLOCKING_INIT_NOTIFIER_HEAD(c->notifiers);  in freq_constraints_init()
457  * freq_qos_read_value - Get frequency QoS constraint for a given list.
470 			pm_qos_read_value(&qos->min_freq);  in freq_qos_read_value()
475 			pm_qos_read_value(&qos->max_freq);  in freq_qos_read_value()
486  * freq_qos_apply - Add/modify/remove frequency QoS request.
498 	switch(req->type) {  in freq_qos_apply()
500 		ret = pm_qos_update_target(&req->qos->min_freq, &req->pnode,  in freq_qos_apply()
504 		ret = pm_qos_update_target(&req->qos->max_freq, &req->pnode,  in freq_qos_apply()
508 		ret = -EINVAL;  in freq_qos_apply()
515  * freq_qos_add_request - Insert new frequency QoS request into a given list.
521  * Insert a new entry into the @qos list of requests, recompute the effective
535 		return -EINVAL;  in freq_qos_add_request()
539 		return -EINVAL;  in freq_qos_add_request()
541 	req->qos = qos;  in freq_qos_add_request()
542 	req->type = type;  in freq_qos_add_request()
545 		req->qos = NULL;  in freq_qos_add_request()
546 		req->type = 0;  in freq_qos_add_request()
554  * freq_qos_update_request - Modify existing frequency QoS request.
567 		return -EINVAL;  in freq_qos_update_request()
571 		return -EINVAL;  in freq_qos_update_request()
573 	if (req->pnode.prio == new_value)  in freq_qos_update_request()
581  * freq_qos_remove_request - Remove frequency QoS request from its list.
595 		return -EINVAL;  in freq_qos_remove_request()
599 		return -EINVAL;  in freq_qos_remove_request()
602 	req->qos = NULL;  in freq_qos_remove_request()
603 	req->type = 0;  in freq_qos_remove_request()
610  * freq_qos_add_notifier - Add frequency QoS change notifier.
622 		return -EINVAL;  in freq_qos_add_notifier()
626 		ret = blocking_notifier_chain_register(qos->min_freq.notifiers,  in freq_qos_add_notifier()
630 		ret = blocking_notifier_chain_register(qos->max_freq.notifiers,  in freq_qos_add_notifier()
635 		ret = -EINVAL;  in freq_qos_add_notifier()
643  * freq_qos_remove_notifier - Remove frequency QoS change notifier.
655 		return -EINVAL;  in freq_qos_remove_notifier()
659 		ret = blocking_notifier_chain_unregister(qos->min_freq.notifiers,  in freq_qos_remove_notifier()
663 		ret = blocking_notifier_chain_unregister(qos->max_freq.notifiers,  in freq_qos_remove_notifier()
668 		ret = -EINVAL;  in freq_qos_remove_notifier()