From b02f6695f7601c4f8442b9cf4636802e7fa8d550 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2014 00:35:23 +0100 Subject: PM / QoS: Rename device resume latency QoS items Rename symbols, variables, functions and structure fields related do the resume latency device PM QoS type so that it is clear where they belong (in particular, to avoid confusion with the latency tolerance device PM QoS type introduced by a subsequent changeset). Update the PM QoS documentation to better reflect its current state. Signed-off-by: Rafael J. Wysocki --- include/linux/pm_qos.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'include/linux/pm_qos.h') diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 5a95013905c8..88a3680ae74c 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -32,7 +32,7 @@ enum pm_qos_flags_status { #define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC) #define PM_QOS_NETWORK_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC) #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE 0 -#define PM_QOS_DEV_LAT_DEFAULT_VALUE 0 +#define PM_QOS_RESUME_LATENCY_DEFAULT_VALUE 0 #define PM_QOS_FLAG_NO_POWER_OFF (1 << 0) #define PM_QOS_FLAG_REMOTE_WAKEUP (1 << 1) @@ -49,7 +49,7 @@ struct pm_qos_flags_request { }; enum dev_pm_qos_req_type { - DEV_PM_QOS_LATENCY = 1, + DEV_PM_QOS_RESUME_LATENCY = 1, DEV_PM_QOS_FLAGS, }; @@ -87,9 +87,9 @@ struct pm_qos_flags { }; struct dev_pm_qos { - struct pm_qos_constraints latency; + struct pm_qos_constraints resume_latency; struct pm_qos_flags flags; - struct dev_pm_qos_request *latency_req; + struct dev_pm_qos_request *resume_latency_req; struct dev_pm_qos_request *flags_req; }; @@ -196,9 +196,9 @@ int dev_pm_qos_expose_flags(struct device *dev, s32 value); void dev_pm_qos_hide_flags(struct device *dev); int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set); -static inline s32 dev_pm_qos_requested_latency(struct device *dev) +static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev) { - return dev->power.qos->latency_req->data.pnode.prio; + return dev->power.qos->resume_latency_req->data.pnode.prio; } static inline s32 dev_pm_qos_requested_flags(struct device *dev) @@ -215,7 +215,7 @@ static inline void dev_pm_qos_hide_flags(struct device *dev) {} static inline int dev_pm_qos_update_flags(struct device *dev, s32 m, bool set) { return 0; } -static inline s32 dev_pm_qos_requested_latency(struct device *dev) { return 0; } +static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev) { return 0; } static inline s32 dev_pm_qos_requested_flags(struct device *dev) { return 0; } #endif -- cgit v1.2.3 From 327adaedf2218b0e318eb393aa79cf2be64c199f Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2014 00:35:29 +0100 Subject: PM / QoS: Add no_constraints_value field to struct pm_qos_constraints Add a new field, no_constraints_value, to struct pm_qos_constraints representing a list of PM QoS constraint requests to be returned by pm_qos_get_value() when that list of requests is empty. That field will be equal to default_value for all of the existing global PM QoS classes and for the resume latency device PM QoS type, but it will be different from default_value for the new latency tolerance device PM QoS type introduced by the next changeset. Signed-off-by: Rafael J. Wysocki --- include/linux/pm_qos.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/pm_qos.h') diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 88a3680ae74c..2d8ce50877d8 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -77,6 +77,7 @@ struct pm_qos_constraints { struct plist_head list; s32 target_value; /* Do not change to 64 bit */ s32 default_value; + s32 no_constraint_value; enum pm_qos_type type; struct blocking_notifier_head *notifiers; }; -- cgit v1.2.3 From 2d984ad132a87ca2112f81f21039493176a8bca0 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2014 00:35:38 +0100 Subject: PM / QoS: Introcuce latency tolerance device PM QoS type Add a new latency tolerance device PM QoS type to be use for specifying active state (RPM_ACTIVE) memory access (DMA) latency tolerance requirements for devices. It may be used to prevent hardware from choosing overly aggressive energy-saving operation modes (causing too much latency to appear) for the whole platform. This feature reqiures hardware support, so it only will be available for devices having a new .set_latency_tolerance() callback in struct dev_pm_info populated, in which case the routine pointed to by it should implement whatever is necessary to transfer the effective requirement value to the hardware. Whenever the effective latency tolerance changes for the device, its .set_latency_tolerance() callback will be executed and the effective value will be passed to it. If that value is negative, which means that the list of latency tolerance requirements for the device is empty, the callback is expected to switch the underlying hardware latency tolerance control mechanism to an autonomous mode if available. If that value is PM_QOS_LATENCY_ANY, in turn, and the hardware supports a special "no requirement" setting, the callback is expected to use it. That allows software to prevent the hardware from automatically updating the device's latency tolerance in response to its power state changes (e.g. during transitions from D3cold to D0), which generally may be done in the autonomous latency tolerance control mode. If .set_latency_tolerance() is present for the device, a new pm_qos_latency_tolerance_us attribute will be present in the devivce's power directory in sysfs. Then, user space can use that attribute to specify its latency tolerance requirement for the device, if any. Writing "any" to it means "no requirement, but do not let the hardware control latency tolerance" and writing "auto" to it allows the hardware to be switched to the autonomous mode if there are no other requirements from the kernel side in the device's list. This changeset includes a fix from Mika Westerberg. Signed-off-by: Rafael J. Wysocki --- include/linux/pm_qos.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include/linux/pm_qos.h') diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 2d8ce50877d8..0b476019be55 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -33,6 +33,9 @@ enum pm_qos_flags_status { #define PM_QOS_NETWORK_LAT_DEFAULT_VALUE (2000 * USEC_PER_SEC) #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE 0 #define PM_QOS_RESUME_LATENCY_DEFAULT_VALUE 0 +#define PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE 0 +#define PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT (-1) +#define PM_QOS_LATENCY_ANY ((s32)(~(__u32)0 >> 1)) #define PM_QOS_FLAG_NO_POWER_OFF (1 << 0) #define PM_QOS_FLAG_REMOTE_WAKEUP (1 << 1) @@ -50,6 +53,7 @@ struct pm_qos_flags_request { enum dev_pm_qos_req_type { DEV_PM_QOS_RESUME_LATENCY = 1, + DEV_PM_QOS_LATENCY_TOLERANCE, DEV_PM_QOS_FLAGS, }; @@ -89,8 +93,10 @@ struct pm_qos_flags { struct dev_pm_qos { struct pm_qos_constraints resume_latency; + struct pm_qos_constraints latency_tolerance; struct pm_qos_flags flags; struct dev_pm_qos_request *resume_latency_req; + struct dev_pm_qos_request *latency_tolerance_req; struct dev_pm_qos_request *flags_req; }; @@ -196,6 +202,8 @@ void dev_pm_qos_hide_latency_limit(struct device *dev); int dev_pm_qos_expose_flags(struct device *dev, s32 value); void dev_pm_qos_hide_flags(struct device *dev); int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set); +s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev); +int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val); static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev) { @@ -215,6 +223,10 @@ static inline int dev_pm_qos_expose_flags(struct device *dev, s32 value) static inline void dev_pm_qos_hide_flags(struct device *dev) {} static inline int dev_pm_qos_update_flags(struct device *dev, s32 m, bool set) { return 0; } +static inline s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev) + { return PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT; } +static inline int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val) + { return 0; } static inline s32 dev_pm_qos_requested_resume_latency(struct device *dev) { return 0; } static inline s32 dev_pm_qos_requested_flags(struct device *dev) { return 0; } -- cgit v1.2.3 From 71d821fdaec08afcbfb3cf258c0d64ea0e336ff3 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2014 00:36:00 +0100 Subject: PM / QoS: Add type to dev_pm_qos_add_ancestor_request() arguments Rework dev_pm_qos_add_ancestor_request() so that device PM QoS type is passed to it as the third argument and make it support the DEV_PM_QOS_LATENCY_TOLERANCE device PM QoS type (in addition to DEV_PM_QOS_RESUME_LATENCY). That will allow the drivers of devices without latency tolerance hardware support to use their ancestors having it as proxies for their latency tolerance requirements. Signed-off-by: Rafael J. Wysocki --- include/linux/pm_qos.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'include/linux/pm_qos.h') diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 0b476019be55..9ab4bf7c4646 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -149,7 +149,8 @@ int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier); void dev_pm_qos_constraints_init(struct device *dev); void dev_pm_qos_constraints_destroy(struct device *dev); int dev_pm_qos_add_ancestor_request(struct device *dev, - struct dev_pm_qos_request *req, s32 value); + struct dev_pm_qos_request *req, + enum dev_pm_qos_req_type type, s32 value); #else static inline enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask) @@ -192,7 +193,9 @@ static inline void dev_pm_qos_constraints_destroy(struct device *dev) dev->power.power_state = PMSG_INVALID; } static inline int dev_pm_qos_add_ancestor_request(struct device *dev, - struct dev_pm_qos_request *req, s32 value) + struct dev_pm_qos_request *req, + enum dev_pm_qos_req_type type, + s32 value) { return 0; } #endif -- cgit v1.2.3