Added power cap framework documentation. This explains the use of power capping framework, sys-fs and programming interface.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruv...@linux.intel.com> --- Documentation/powercap/PowerCappingFramework.txt | 1008 ++++++++++++++++++++++ 1 file changed, 1008 insertions(+) create mode 100644 Documentation/powercap/PowerCappingFramework.txt diff --git a/Documentation/powercap/PowerCappingFramework.txt b/Documentation/powercap/PowerCappingFramework.txt new file mode 100644 index 0000000..76eb63d --- /dev/null +++ b/Documentation/powercap/PowerCappingFramework.txt @@ -0,0 +1,1008 @@ +Power Capping Framework +================================== + +The Linux Power Capping Framework provides user-space with a common +API to kernel-mode power-capping drivers. At the same time, +it provides the hardware-specific power-capping drivers with +a uniform API to user-space. + +Terminology +========================= +The Power Capping framework organizes power capping devices under a tree structure. +At the root level, each device is under some "controller", which is the enabler +of technology. For example this can be "RAPL". +Under each controllers, there are multiple power zones, which can be independently +monitored and controlled using this technology. +Each power zone can be organized as a tree with parent, children and siblings. +Each power zone defines attributes to enable power monitoring and apply +constraints on power consumption. + +For example, using RAPL, one can independently control CPU packages. Each package is +further divided in to multiple domains for core uncore, dram devices, which can +be independently controlled. As the technology gets matured, each uncore and core, +devices will be further divided into multiple domain. Here domains are called "zones" +in this documentation. + + +Experimental implantation is using two options: +Option 1: Use simple device model. Since we can't have duplicate file names under +a class even if there parents are different (Unlike a Linux directory tree), each +child will be named using their hierarchy in the tree. For example, a RAPL power +zone such as a CPU package can be called intel-rapl-0, then its children will be +named as intel-rapl-0:0, intel-rapl-0:1 etc. + +Option 2: Each controller is a device and zones and constraints under it are +created using kobjects. Here exact names of power zones can be used in the sys-fs +file names. + +The two tree's below presents representation using above options. +In this system RAPL functionality is implemented in a client driver using power-capping +framework described here. The sys-fs tree below is generated on a server system, +with two CPU packages. Each package is further divided into "core", and "dram". +============================ +Option 1 + +/sys/devices/virtual/power_cap +└── intel-rapl + ├── intel-rapl:0 + │ ├── constraint_0_name + │ ├── constraint_0_power_limit_uw + │ ├── constraint_0_time_window_us + │ ├── constraint_1_name + │ ├── constraint_1_power_limit_uw + │ ├── constraint_1_time_window_us + │ ├── device -> ../../intel-rapl [recursive, not followed] + │ ├── energy_uj + │ ├── intel-rapl:0:0 + │ │ ├── constraint_0_name + │ │ ├── constraint_0_power_limit_uw + │ │ ├── constraint_0_time_window_us + │ │ ├── device -> ../../intel-rapl:0 [recursive, not followed] + │ │ ├── energy_uj + │ │ ├── max_energy_range_uj + │ │ ├── name + │ │ ├── power + │ │ │ ├── async + │ │ │ ├── autosuspend_delay_ms + │ │ │ ├── control + │ │ │ ├── runtime_active_kids + │ │ │ ├── runtime_active_time + │ │ │ ├── runtime_enabled + │ │ │ ├── runtime_status + │ │ │ ├── runtime_suspended_time + │ │ │ └── runtime_usage + │ │ ├── subsystem -> ../../../../../../class/power_cap + │ │ │ ├── intel-rapl -> ../../devices/virtual/power_cap/intel-rapl [recursive, not followed] + │ │ │ ├── intel-rapl:0 -> ../../devices/virtual/power_cap/intel-rapl/intel-rapl:0 [recursive, not followed] + │ │ │ ├── intel-rapl:0:0 -> ../../devices/virtual/power_cap/intel-rapl/intel-rapl:0/intel-rapl:0:0 [recursive, not followed] + │ │ │ ├── intel-rapl:0:1 -> ../../devices/virtual/power_cap/intel-rapl/intel-rapl:0/intel-rapl:0:1 + │ │ │ │ ├── constraint_0_name + │ │ │ │ ├── constraint_0_power_limit_uw + │ │ │ │ ├── constraint_0_time_window_us + │ │ │ │ ├── device -> ../../intel-rapl:0 [recursive, not followed] + │ │ │ │ ├── energy_uj + │ │ │ │ ├── max_energy_range_uj + │ │ │ │ ├── name + │ │ │ │ ├── power + │ │ │ │ │ ├── async + │ │ │ │ │ ├── autosuspend_delay_ms + │ │ │ │ │ ├── control + │ │ │ │ │ ├── runtime_active_kids + │ │ │ │ │ ├── runtime_active_time + │ │ │ │ │ ├── runtime_enabled + │ │ │ │ │ ├── runtime_status + │ │ │ │ │ ├── runtime_suspended_time + │ │ │ │ │ └── runtime_usage + │ │ │ │ ├── subsystem -> ../../../../../../class/power_cap [recursive, not followed] + │ │ │ │ └── uevent + │ │ │ ├── intel-rapl:1 -> ../../devices/virtual/power_cap/intel-rapl/intel-rapl:1 + │ │ │ │ ├── constraint_0_name + │ │ │ │ ├── constraint_0_power_limit_uw + │ │ │ │ ├── constraint_0_time_window_us + │ │ │ │ ├── constraint_1_name + │ │ │ │ ├── constraint_1_power_limit_uw + │ │ │ │ ├── constraint_1_time_window_us + │ │ │ │ ├── device -> ../../intel-rapl [recursive, not followed] + │ │ │ │ ├── energy_uj + │ │ │ │ ├── intel-rapl:1:0 + │ │ │ │ │ ├── constraint_0_name + │ │ │ │ │ ├── constraint_0_power_limit_uw + │ │ │ │ │ ├── constraint_0_time_window_us + │ │ │ │ │ ├── device -> ../../intel-rapl:1 [recursive, not followed] + │ │ │ │ │ ├── energy_uj + │ │ │ │ │ ├── max_energy_range_uj + │ │ │ │ │ ├── name + │ │ │ │ │ ├── power + │ │ │ │ │ │ ├── async + │ │ │ │ │ │ ├── autosuspend_delay_ms + │ │ │ │ │ │ ├── control + │ │ │ │ │ │ ├── runtime_active_kids + │ │ │ │ │ │ ├── runtime_active_time + │ │ │ │ │ │ ├── runtime_enabled + │ │ │ │ │ │ ├── runtime_status + │ │ │ │ │ │ ├── runtime_suspended_time + │ │ │ │ │ │ └── runtime_usage + │ │ │ │ │ ├── subsystem -> ../../../../../../class/power_cap [recursive, not followed] + │ │ │ │ │ └── uevent + │ │ │ │ ├── intel-rapl:1:1 + │ │ │ │ │ ├── constraint_0_name + │ │ │ │ │ ├── constraint_0_power_limit_uw + │ │ │ │ │ ├── constraint_0_time_window_us + │ │ │ │ │ ├── device -> ../../intel-rapl:1 [recursive, not followed] + │ │ │ │ │ ├── energy_uj + │ │ │ │ │ ├── max_energy_range_uj + │ │ │ │ │ ├── name + │ │ │ │ │ ├── power + │ │ │ │ │ │ ├── async + │ │ │ │ │ │ ├── autosuspend_delay_ms + │ │ │ │ │ │ ├── control + │ │ │ │ │ │ ├── runtime_active_kids + │ │ │ │ │ │ ├── runtime_active_time + │ │ │ │ │ │ ├── runtime_enabled + │ │ │ │ │ │ ├── runtime_status + │ │ │ │ │ │ ├── runtime_suspended_time + │ │ │ │ │ │ └── runtime_usage + │ │ │ │ │ ├── subsystem -> ../../../../../../class/power_cap [recursive, not followed] + │ │ │ │ │ └── uevent + │ │ │ │ ├── max_energy_range_uj + │ │ │ │ ├── max_power_range_uw + │ │ │ │ ├── name + │ │ │ │ ├── power + │ │ │ │ │ ├── async + │ │ │ │ │ ├── autosuspend_delay_ms + │ │ │ │ │ ├── control + │ │ │ │ │ ├── runtime_active_kids + │ │ │ │ │ ├── runtime_active_time + │ │ │ │ │ ├── runtime_enabled + │ │ │ │ │ ├── runtime_status + │ │ │ │ │ ├── runtime_suspended_time + │ │ │ │ │ └── runtime_usage + │ │ │ │ ├── subsystem -> ../../../../../class/power_cap [recursive, not followed] + │ │ │ │ └── uevent + │ │ │ ├── intel-rapl:1:0 -> ../../devices/virtual/power_cap/intel-rapl/intel-rapl:1/intel-rapl:1:0 [recursive, not followed] + │ │ │ └── intel-rapl:1:1 -> ../../devices/virtual/power_cap/intel-rapl/intel-rapl:1/intel-rapl:1:1 [recursive, not followed] + │ │ └── uevent + │ ├── intel-rapl:0:1 + │ │ ├── constraint_0_name + │ │ ├── constraint_0_power_limit_uw + │ │ ├── constraint_0_time_window_us + │ │ ├── device -> ../../intel-rapl:0 [recursive, not followed] + │ │ ├── energy_uj + │ │ ├── max_energy_range_uj + │ │ ├── name + │ │ ├── power + │ │ │ ├── async + │ │ │ ├── autosuspend_delay_ms + │ │ │ ├── control + │ │ │ ├── runtime_active_kids + │ │ │ ├── runtime_active_time + │ │ │ ├── runtime_enabled + │ │ │ ├── runtime_status + │ │ │ ├── runtime_suspended_time + │ │ │ └── runtime_usage + │ │ ├── subsystem -> ../../../../../../class/power_cap [recursive, not followed] + │ │ └── uevent + │ ├── max_energy_range_uj + │ ├── max_power_range_uw + │ ├── name + │ ├── power + │ │ ├── async + │ │ ├── autosuspend_delay_ms + │ │ ├── control + │ │ ├── runtime_active_kids + │ │ ├── runtime_active_time + │ │ ├── runtime_enabled + │ │ ├── runtime_status + │ │ ├── runtime_suspended_time + │ │ └── runtime_usage + │ ├── subsystem -> ../../../../../class/power_cap [recursive, not followed] + │ └── uevent + ├── intel-rapl:1 + │ ├── constraint_0_name + │ ├── constraint_0_power_limit_uw + │ ├── constraint_0_time_window_us + │ ├── constraint_1_name + │ ├── constraint_1_power_limit_uw + │ ├── constraint_1_time_window_us + │ ├── device -> ../../intel-rapl [recursive, not followed] + │ ├── energy_uj + │ ├── intel-rapl:1:0 + │ │ ├── constraint_0_name + │ │ ├── constraint_0_power_limit_uw + │ │ ├── constraint_0_time_window_us + │ │ ├── device -> ../../intel-rapl:1 [recursive, not followed] + │ │ ├── energy_uj + │ │ ├── max_energy_range_uj + │ │ ├── name + │ │ ├── power + │ │ │ ├── async + │ │ │ ├── autosuspend_delay_ms + │ │ │ ├── control + │ │ │ ├── runtime_active_kids + │ │ │ ├── runtime_active_time + │ │ │ ├── runtime_enabled + │ │ │ ├── runtime_status + │ │ │ ├── runtime_suspended_time + │ │ │ └── runtime_usage + │ │ ├── subsystem -> ../../../../../../class/power_cap [recursive, not followed] + │ │ └── uevent + │ ├── intel-rapl:1:1 + │ │ ├── constraint_0_name + │ │ ├── constraint_0_power_limit_uw + │ │ ├── constraint_0_time_window_us + │ │ ├── device -> ../../intel-rapl:1 [recursive, not followed] + │ │ ├── energy_uj + │ │ ├── max_energy_range_uj + │ │ ├── name + │ │ ├── power + │ │ │ ├── async + │ │ │ ├── autosuspend_delay_ms + │ │ │ ├── control + │ │ │ ├── runtime_active_kids + │ │ │ ├── runtime_active_time + │ │ │ ├── runtime_enabled + │ │ │ ├── runtime_status + │ │ │ ├── runtime_suspended_time + │ │ │ └── runtime_usage + │ │ ├── subsystem -> ../../../../../../class/power_cap [recursive, not followed] + │ │ └── uevent + │ ├── max_energy_range_uj + │ ├── max_power_range_uw + │ ├── name + │ ├── power + │ │ ├── async + │ │ ├── autosuspend_delay_ms + │ │ ├── control + │ │ ├── runtime_active_kids + │ │ ├── runtime_active_time + │ │ ├── runtime_enabled + │ │ ├── runtime_status + │ │ ├── runtime_suspended_time + │ │ └── runtime_usage + │ ├── subsystem -> ../../../../../class/power_cap [recursive, not followed] + │ └── uevent + ├── power + │ ├── async + │ ├── autosuspend_delay_ms + │ ├── control + │ ├── runtime_active_kids + │ ├── runtime_active_time + │ ├── runtime_enabled + │ ├── runtime_status + │ ├── runtime_suspended_time + │ └── runtime_usage + ├── subsystem -> ../../../../class/power_cap [recursive, not followed] + └── uevent + +============================= +Option 2 + +/sys/devices/virtual/power_cap +└── intel-rapl + ├── package-0 + │ ├── constraint-0 + │ │ ├── name + │ │ ├── power_limit_uw + │ │ └── time_window_us + │ ├── constraint-1 + │ │ ├── name + │ │ ├── power_limit_uw + │ │ └── time_window_us + │ ├── core + │ │ ├── constraint-0 + │ │ │ ├── name + │ │ │ ├── power_limit_uw + │ │ │ └── time_window_us + │ │ ├── energy_uj + │ │ └── max_energy_range_uj + │ ├── dram + │ │ ├── constraint-0 + │ │ │ ├── name + │ │ │ ├── power_limit_uw + │ │ │ └── time_window_us + │ │ ├── energy_uj + │ │ └── max_energy_range_uj + │ ├── energy_uj + │ ├── max_energy_range_uj + │ └── max_power_range_uw + ├── package-1 + │ ├── constraint-0 + │ │ ├── name + │ │ ├── power_limit_uw + │ │ └── time_window_us + │ ├── constraint-1 + │ │ ├── name + │ │ ├── power_limit_uw + │ │ └── time_window_us + │ ├── core + │ │ ├── constraint-0 + │ │ │ ├── name + │ │ │ ├── power_limit_uw + │ │ │ └── time_window_us + │ │ ├── energy_uj + │ │ └── max_energy_range_uj + │ ├── dram + │ │ ├── constraint-0 + │ │ │ ├── name + │ │ │ ├── power_limit_uw + │ │ │ └── time_window_us + │ │ ├── energy_uj + │ │ └── max_energy_range_uj + │ ├── energy_uj + │ ├── max_energy_range_uj + │ └── max_power_range_uw + ├── power + │ ├── async + │ ├── autosuspend_delay_ms + │ ├── control + │ ├── runtime_active_kids + │ ├── runtime_active_time + │ ├── runtime_enabled + │ ├── runtime_status + │ ├── runtime_suspended_time + │ └── runtime_usage + ├── subsystem -> ../../../../class/power_cap + │ └── intel-rapl -> ../../devices/virtual/power_cap/intel-rapl [recursive, not followed] + └── uevent + +18 directories, 48 files + + +================================= + +Power Zone Attributes +================================= +Monitoring attributes +---------------------- + +energy_uj (rw): Current energy counter in micro-joules. Write to energy counter +resets the counter to zero. If the counter can not be reset, then this attribute +is read-only. + +max_energy_range_uj (r): Range of the above energy counter in micro-joules. + +power_uw (rw): Current power counter in micro-watts. Write to this counter +resets the counter to zero. If the counter can not be reset, then this attribute +is read-only. +max_power_range_uw (r): Range of the above energy counter in micro-watts. + +It is possible that some domains can have both power and energy counters and +ranges, but at least one is mandatory. + +Constraints +---------------- +power_limit_uw (rw): Power limit in micro-watts, which should be applicable for +the time window specified by "time_window_us". +time_window_us (rw): Time window in micro seconds. +name (ro): An optional name of the constraint + +Power Cap Client Driver Interface +================================== + +Interface API +---------------------------------- +powercap_allocate_controller - Allocates a controller + +Synopsis: + +void * powercap_allocate_controller (const char * controller_name); + +Arguments: + +controller_name + The Name of this controller, which will be shown + in the Sys-Fs Interface. + + +Description: + +Used to create a controller with the power capping class. Here controller +can represent a type of technology, which can control a range of power zones. +For example a controller can be RAPL (Running Average Power Limit) +Intel® 64 and IA-32 Processor Architectures. The name can be any string +which must be unique, otherwise this function returns NULL. +On successful allocation, this API returns a pointer to the +controller instance. + + +Name: + +powercap_deallocate_controller - Deallocates a controller + +Synopsis: + +void powercap_deallocate_controller (void * instance); + +Arguments: + +instance + A pointer to the valid controller instance. + + +Description: + +Used to deallocate a controller with the power capping class. This +takes only one argument, which is the pointer to the instance returned +by a call to powercap_allocate_controller. +When a controller is deallocated, all zones and associated constraints +are freed. + + +Name: + +powercap_zone_register - Register a power zone + +Synopsis: + +struct powercap_zone_device * powercap_zone_register (void * controller, + const char * name, + const struct powercap_zone_ops * ops, + struct powercap_zone_device * parent); + +Arguments: + +controller + A controller instance under which this zone operates. + +name + A name for this zone, this will appear in Sys-Fs I/F under + a controller or a parent zone name. + +ops + Pointer to zone operation callback structure. + +parent + A pointer to the parent power zone instance if any or NULL + + +Description: + +Used to register a power zone for a controller. Zones are organized in +a tree like structure in Sys-Fs under a controller. A power zone name +may not be unique, if they are in different level of hierarchy similar to +a file system directory tree. +A power zone must a register a pointer to a structure representing zone +callbacks. +A power zone can have a some other power zone as a parent or it can be +NULL to appear as a direct descendant of a controller. + + +Name: + +powercap_zone_unregister - Unregister a zone device + +Synopsis: + +int powercap_zone_unregister (void * controller, + struct powercap_zone_device * pcd_dev); + +Arguments: + +controller + A pointer to the valid instance of a controller. + +pcd_dev + A pointer to the valid zone instance for a controller + + +Description: + +Used to unregister a zone device for a controller. Once a zone is +unregistered then all its children and associated constraints are freed. + + +Name: + +powercap_zone_add_constraint - Register a constraint + +Synopsis: + +struct powercap_zone_constraint * powercap_zone_add_constraint (struct powercap_zone_device * pcd_dev, + struct powercap_zone_constraint_ops * ops); + +Arguments: + +pcd_dev + A pointer to the valid zone instance + +ops + A pointer to the structure defining constraint callbacks + + +Description: + +Used to unregister a register a constraint. Multiple constraints can be +registered to a zone. Each constraint define some power limits and a time +window over which this constraint is applicable. Time window and power limit +should be with in limits specified in the corresponding max/min limits. +On successful registration, it returns a pointer an instance of a constraint. + + +Name: + +powercap_zone_remove_constraint - Unregister a constraint + +Synopsis: + +int powercap_zone_remove_constraint (struct powercap_zone_device * pcd_dev, + struct powercap_zone_constraint * pconst); + +Arguments: + +pcd_dev + A pointer to the valid zone instance + +pconst + A valid constraint instance + + +Description: + +Used to unregister a constraint from a zone. + + +struct powercap_zone_constraint_ops - Define constraint callbacks + +struct powercap_zone_constraint_ops { + int (* set_power_limit_uw) (struct powercap_zone_constraint *, unsigned long); + int (* get_power_limit_uw) (struct powercap_zone_constraint *, unsigned long *); + int (* set_time_window_us) (struct powercap_zone_constraint *, unsigned long); + int (* get_time_window_us) (struct powercap_zone_constraint *, unsigned long *); + int (* get_max_power_uw) (struct powercap_zone_constraint *, unsigned long *); + int (* get_min_power_uw) (struct powercap_zone_constraint *, unsigned long *); + int (* get_max_time_window_us) (struct powercap_zone_constraint *, unsigned long *); + int (* get_min_time_window_us) (struct powercap_zone_constraint *, unsigned long *); +}; + +Members: + +set_power_limit_uw + Set power limit in micro-watts. + +get_power_limit_uw + Get power limit in micro-watts. + +set_time_window_us + Set time window in micro-seconds. + +get_time_window_us + Get time window in micro-seconds. + +get_max_power_uw + Get max power allowed in micro-watts. + +get_min_power_uw + Get min power allowed in micro-watts. + +get_max_time_window_us + Get max time window allowed in micro-seconds. + +get_min_time_window_us + Get min time window allowed in micro-seconds. + + + +Description: + +This structure is used to define the constraint callbacks for the client +drivers. The following callbacks are mandatory and can't be NULL: +set_power_limit_uw +get_power_limit_uw +set_time_window_us +get_time_window_us + + +struct powercap_zone_constraint - Defines instance of a constraint + +struct powercap_zone_constraint { + int id; + struct kobject kobj; + struct completion kobj_unregister; + struct powercap_zone_device * pcd_dev; + struct powercap_zone_constraint_ops * ops; + struct list_head node; +}; + +Members: + +id + Instance Id of this constraint. + +kobj + Kobject instance. + +kobj_unregister + Used for block on this completion variable + +pcd_dev + Pointer to the power zone for this constraint. + +ops + Pointer to the constraint callbacks. + +node + Link to other constraints for this power zone. + + + +Description: + +This defines a constraint instance. The fields of this structure are +private, and should not be used by client drivers. + + +struct powercap_zone_ops - Define power zone callbacks + +struct powercap_zone_ops { + int (* get_max_energy_range_uj) (struct powercap_zone_device *, unsigned long *); + int (* get_energy_uj) (struct powercap_zone_device *, unsigned long *); + int (* reset_energy_uj) (struct powercap_zone_device *); + int (* get_max_power_range_uw) (struct powercap_zone_device *, unsigned long *); + int (* get_power_uw) (struct powercap_zone_device *, unsigned long *); + int (* reset_power_uw) (struct powercap_zone_device *); +}; + +Members: + +get_max_energy_range_uj + Get maximum range of energy counter in + micro-joules. + +get_energy_uj + Get current energy counter in micro-joules. + +reset_energy_uj + Reset micro-joules energy counter. + +get_max_power_range_uw + Get maximum range of power counter in + micro-watts. + +get_power_uw + Get current power counter in micro-watts. + +reset_power_uw + Reset micro-watts power counter. + + + +Description: + +This structure defines zone callbacks to be implemented by client drivers. +Client drives can define both energy and power related callbacks. But at +the least one type (either power or energy) is mandatory. + + +struct powercap_zone_device - Defines instance of a power cap zone + +struct powercap_zone_device { + char name[POWERCAP_ZONE_NAME_LENGTH]; + const struct powercap_zone_ops * ops; + struct kobject kobj; + void * node; + struct completion kobj_unregister; + struct mutex lock; + struct idr idr; + struct list_head constraint_list; +}; + +Members: + +name[POWERCAP_ZONE_NAME_LENGTH] + Power zone name. + +ops + Pointer to the zone operation structure. + +kobj + Instance of a kobj. + +node + Node pointer to insert to a tree data structure. + +kobj_unregister + Used for block on this completion variable. + +lock + Mutex to protect zone related operations. + +idr + Instance to an idr entry. + +constraint_list + Link to the next power zone for this controller. + + + +Description: + +This defines a power zone instance. The fields of this structure are +private, and should not be used by client drivers. + + +struct powercap_zone_constraint_ops - Define constraint callbacks + +struct powercap_zone_constraint_ops { + int (* set_power_limit_uw) (struct powercap_zone_constraint *, unsigned long); + int (* get_power_limit_uw) (struct powercap_zone_constraint *, unsigned long *); + int (* set_time_window_us) (struct powercap_zone_constraint *, unsigned long); + int (* get_time_window_us) (struct powercap_zone_constraint *, unsigned long *); + int (* get_max_power_uw) (struct powercap_zone_constraint *, unsigned long *); + int (* get_min_power_uw) (struct powercap_zone_constraint *, unsigned long *); + int (* get_max_time_window_us) (struct powercap_zone_constraint *, unsigned long *); + int (* get_min_time_window_us) (struct powercap_zone_constraint *, unsigned long *); + char *(* get_name) (struct powercap_zone_constraint *); + void (* cleanup) (struct powercap_zone_constraint *); +}; + +Members: + +set_power_limit_uw + Set power limit in micro-watts. + +get_power_limit_uw + Get power limit in micro-watts. + +set_time_window_us + Set time window in micro-seconds. + +get_time_window_us + Get time window in micro-seconds. + +get_max_power_uw + Get max power allowed in micro-watts. + +get_min_power_uw + Get min power allowed in micro-watts. + +get_max_time_window_us + Get max time window allowed in micro-seconds. + +get_min_time_window_us + Get min time window allowed in micro-seconds. + +get_name + Get the name of constraint + +cleanup + Do any clean up before the constraint is freed +This structure is used to define the constraint callbacks for the client +drivers. The following callbacks are mandatory and can't be NULL: + set_power_limit_uw + get_power_limit_uw + set_time_window_us + get_time_window_us + + + + + +struct powercap_zone_constraint - Defines instance of a constraint + +struct powercap_zone_constraint { + int id; + struct kobject kobj; + struct completion kobj_unregister; + struct powercap_zone_device * pcd_dev; + struct powercap_zone_constraint_ops * ops; + void * drv_data; + struct list_head node; +}; + +Members: + +id + Instance Id of this constraint. + +kobj + Kobject instance. + +kobj_unregister + Used for block on this completion variable + +pcd_dev + Pointer to the power zone for this constraint. + +ops + Pointer to the constraint callbacks. + +drv_data + Driver private data + +node + Link to other constraints for this power zone. + + + +Description: + +This defines a constraint instance. The fields of this structure are +private, and should not be used by client drivers. + + +struct powercap_zone_ops - Define power zone callbacks + +struct powercap_zone_ops { + int (* get_max_energy_range_uj) (struct powercap_zone_device *, unsigned long *); + int (* get_energy_uj) (struct powercap_zone_device *, unsigned long *); + int (* reset_energy_uj) (struct powercap_zone_device *); + int (* get_max_power_range_uw) (struct powercap_zone_device *, unsigned long *); + int (* get_power_uw) (struct powercap_zone_device *, unsigned long *); + int (* reset_power_uw) (struct powercap_zone_device *); + void (* cleanup) (struct powercap_zone_device *); +}; + +Members: + +get_max_energy_range_uj + Get maximum range of energy counter in + micro-joules. + +get_energy_uj + Get current energy counter in micro-joules. + +reset_energy_uj + Reset micro-joules energy counter. + +get_max_power_range_uw + Get maximum range of power counter in + micro-watts. + +get_power_uw + Get current power counter in micro-watts. + +reset_power_uw + Reset micro-watts power counter. + +cleanup + Do any clean up before the zone is freed + + + +Description: + +This structure defines zone callbacks to be implemented by client drivers. +Client drives can define both energy and power related callbacks. But at +the least one type (either power or energy) is mandatory. + + +struct powercap_zone_device - Defines instance of a power cap zone + +struct powercap_zone_device { + char name[POWERCAP_ZONE_NAME_LENGTH]; + void * controller_inst; + const struct powercap_zone_ops * ops; + struct kobject kobj; + void * node; + struct completion kobj_unregister; + struct mutex lock; + struct idr idr; + void * drv_data; + struct list_head constraint_list; +}; + +Members: + +name[POWERCAP_ZONE_NAME_LENGTH] + Power zone name. + +controller_inst + Controller instance for this zone + +ops + Pointer to the zone operation structure. + +kobj + Instance of a kobj. + +node + Node pointer to insert to a tree data structure. + +kobj_unregister + Used for block on this completion variable. + +lock + Mutex to protect zone related operations. + +idr + Instance to an idr entry. + +drv_data + Driver private data + +constraint_list + Link to the next power zone for this controller. + + + +Description: + +This defines a power zone instance. The fields of this structure are +private, and should not be used by client drivers. + + +Name: + +powercap_set_zone_data - Set private data for a zone + +Synopsis: + +void powercap_set_zone_data (struct powercap_zone_device * pcd_dev, + void * pdata); + +Arguments: + +pcd_dev + A pointer to the valid zone instance. + +pdata + A pointer to the user private data. + + +Description: + +Allows client drivers to associate some private data to zone instance. + + +Name: + +powercap_get_zone_data - Get private data for a zone + +Synopsis: + +void * powercap_get_zone_data (struct powercap_zone_device * pcd_dev); + +Arguments: + +pcd_dev + A pointer to the valid zone instance. + + +Description: + +Allows client drivers to get private data associate with a zone, +using call to powercap_set_zone_data. + + +Name: + +powercap_set_constraint_data - Set private data for a constraint + +Synopsis: + +void powercap_set_constraint_data (struct powercap_zone_constraint * pconst, + void * pdata); + +Arguments: + +pconst + A pointer to the valid constraint instance. + +pdata + A pointer to the user private data. + + +Description: + +Allows client drivers to associate some private data to constraint instance. + + +Name: + +powercap_get_constraint_data - Get private data for a constraint + +Synopsis: + +void * powercap_get_constraint_data (struct powercap_zone_constraint * pconst); + +Arguments: + +pconst + A pointer to the valid constraint instance. + + +Description: + +Allows client drivers to get private data associate with a constraint, +using call to powercap_set_constraint_data. + -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/