linux-stable/include/linux/powercap.h
Srinivas Pandruvada 75d2364ea0 PowerCap: Add class driver
The power capping framework providing a consistent interface between the
kernel and user space that allows power capping drivers to expose their
settings to user space in a uniform way.
The overall design of the framework is described in the documentation
added by the previous patch in this series.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-17 00:36:06 +02:00

325 lines
13 KiB
C

/*
* powercap.h: Data types and headers for sysfs power capping interface
* Copyright (c) 2013, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.
*
*/
#ifndef __POWERCAP_H__
#define __POWERCAP_H__
#include <linux/device.h>
#include <linux/idr.h>
/*
* A power cap class device can contain multiple powercap control_types.
* Each control_type can have multiple power zones, which can be independently
* controlled. Each power zone can have one or more constraints.
*/
struct powercap_control_type;
struct powercap_zone;
struct powercap_zone_constraint;
/**
* struct powercap_control_type_ops - Define control type callbacks
* @set_enable: Enable/Disable whole control type.
* Default is enabled. But this callback allows all zones
* to be in disable state and remove any applied power
* limits. If disabled power zone can only be monitored
* not controlled.
* @get_enable: get Enable/Disable status.
* @release: Callback to inform that last reference to this
* control type is closed. So it is safe to free data
* structure associated with this control type.
* This callback is mandatory if the client own memory
* for the control type.
*
* This structure defines control type callbacks to be implemented by client
* drivers
*/
struct powercap_control_type_ops {
int (*set_enable) (struct powercap_control_type *, bool mode);
int (*get_enable) (struct powercap_control_type *, bool *mode);
int (*release) (struct powercap_control_type *);
};
/**
* struct powercap_control_type- Defines a powercap control_type
* @name: name of control_type
* @dev: device for this control_type
* @idr: idr to have unique id for its child
* @root_node: Root holding power zones for this control_type
* @ops: Pointer to callback struct
* @node_lock: mutex for control type
* @allocated: This is possible that client owns the memory
* used by this structure. In this case
* this flag is set to false by framework to
* prevent deallocation during release process.
* Otherwise this flag is set to true.
* @ctrl_inst: link to the control_type list
*
* Defines powercap control_type. This acts as a container for power
* zones, which use same method to control power. E.g. RAPL, RAPL-PCI etc.
* All fields are private and should not be used by client drivers.
*/
struct powercap_control_type {
struct device dev;
struct idr idr;
int nr_zones;
const struct powercap_control_type_ops *ops;
struct mutex lock;
bool allocated;
struct list_head node;
};
/**
* struct powercap_zone_ops - Define power zone callbacks
* @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.
* @set_enable: Enable/Disable power zone controls.
* Default is enabled.
* @get_enable: get Enable/Disable status.
* @release: Callback to inform that last reference to this
* control type is closed. So it is safe to free
* data structure associated with this
* control type. Mandatory, if client driver owns
* the power_zone memory.
*
* 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. Client drivers
* should handle mutual exclusion, if required in callbacks.
*/
struct powercap_zone_ops {
int (*get_max_energy_range_uj) (struct powercap_zone *, u64 *);
int (*get_energy_uj) (struct powercap_zone *, u64 *);
int (*reset_energy_uj) (struct powercap_zone *);
int (*get_max_power_range_uw) (struct powercap_zone *, u64 *);
int (*get_power_uw) (struct powercap_zone *, u64 *);
int (*set_enable) (struct powercap_zone *, bool mode);
int (*get_enable) (struct powercap_zone *, bool *mode);
int (*release) (struct powercap_zone *);
};
#define POWERCAP_ZONE_MAX_ATTRS 6
#define POWERCAP_CONSTRAINTS_ATTRS 8
#define MAX_CONSTRAINTS_PER_ZONE 10
/**
* struct powercap_zone- Defines instance of a power cap zone
* @id: Unique id
* @name: Power zone name.
* @control_type_inst: Control type instance for this zone.
* @ops: Pointer to the zone operation structure.
* @dev: Instance of a device.
* @const_id_cnt: Number of constraint defined.
* @idr: Instance to an idr entry for children zones.
* @parent_idr: To remove reference from the parent idr.
* @private_data: Private data pointer if any for this zone.
* @zone_dev_attrs: Attributes associated with this device.
* @zone_attr_count: Attribute count.
* @dev_zone_attr_group: Attribute group for attributes.
* @dev_attr_groups: Attribute group store to register with device.
* @allocated: This is possible that client owns the memory
* used by this structure. In this case
* this flag is set to false by framework to
* prevent deallocation during release process.
* Otherwise this flag is set to true.
* @constraint_ptr: List of constraints for this zone.
*
* This defines a power zone instance. The fields of this structure are
* private, and should not be used by client drivers.
*/
struct powercap_zone {
int id;
char *name;
void *control_type_inst;
const struct powercap_zone_ops *ops;
struct device dev;
int const_id_cnt;
struct idr idr;
struct idr *parent_idr;
void *private_data;
struct attribute **zone_dev_attrs;
int zone_attr_count;
struct attribute_group dev_zone_attr_group;
const struct attribute_group *dev_attr_groups[2]; /* 1 group + NULL */
bool allocated;
struct powercap_zone_constraint *constraints;
};
/**
* struct powercap_zone_constraint_ops - Define constraint callbacks
* @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
*
* 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
* get_name
* Client drivers should handle mutual exclusion, if required in callbacks.
*/
struct powercap_zone_constraint_ops {
int (*set_power_limit_uw) (struct powercap_zone *, int, u64);
int (*get_power_limit_uw) (struct powercap_zone *, int, u64 *);
int (*set_time_window_us) (struct powercap_zone *, int, u64);
int (*get_time_window_us) (struct powercap_zone *, int, u64 *);
int (*get_max_power_uw) (struct powercap_zone *, int, u64 *);
int (*get_min_power_uw) (struct powercap_zone *, int, u64 *);
int (*get_max_time_window_us) (struct powercap_zone *, int, u64 *);
int (*get_min_time_window_us) (struct powercap_zone *, int, u64 *);
const char *(*get_name) (struct powercap_zone *, int);
};
/**
* struct powercap_zone_constraint- Defines instance of a constraint
* @id: Instance Id of this constraint.
* @power_zone: Pointer to the power zone for this constraint.
* @ops: Pointer to the constraint callbacks.
*
* This defines a constraint instance.
*/
struct powercap_zone_constraint {
int id;
struct powercap_zone *power_zone;
struct powercap_zone_constraint_ops *ops;
};
/* For clients to get their device pointer, may be used for dev_dbgs */
#define POWERCAP_GET_DEV(power_zone) (&power_zone->dev)
/**
* powercap_set_zone_data() - Set private data for a zone
* @power_zone: A pointer to the valid zone instance.
* @pdata: A pointer to the user private data.
*
* Allows client drivers to associate some private data to zone instance.
*/
static inline void powercap_set_zone_data(struct powercap_zone *power_zone,
void *pdata)
{
if (power_zone)
power_zone->private_data = pdata;
}
/**
* powercap_get_zone_data() - Get private data for a zone
* @power_zone: A pointer to the valid zone instance.
*
* Allows client drivers to get private data associate with a zone,
* using call to powercap_set_zone_data.
*/
static inline void *powercap_get_zone_data(struct powercap_zone *power_zone)
{
if (power_zone)
return power_zone->private_data;
return NULL;
}
/**
* powercap_register_control_type() - Register a control_type with framework
* @control_type: Pointer to client allocated memory for the control type
* structure storage. If this is NULL, powercap framework
* will allocate memory and own it.
* Advantage of this parameter is that client can embed
* this data in its data structures and allocate in a
* single call, preventing multiple allocations.
* @control_type_name: The Name of this control_type, which will be shown
* in the sysfs Interface.
* @ops: Callbacks for control type. This parameter is optional.
*
* Used to create a control_type with the power capping class. Here control_type
* can represent a type of technology, which can control a range of power zones.
* For example a control_type 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.
* A pointer to the control_type instance is returned on success.
*/
struct powercap_control_type *powercap_register_control_type(
struct powercap_control_type *control_type,
const char *name,
const struct powercap_control_type_ops *ops);
/**
* powercap_unregister_control_type() - Unregister a control_type from framework
* @instance: A pointer to the valid control_type instance.
*
* Used to unregister a control_type with the power capping class.
* All power zones registered under this control type have to be unregistered
* before calling this function, or it will fail with an error code.
*/
int powercap_unregister_control_type(struct powercap_control_type *instance);
/* Zone register/unregister API */
/**
* powercap_register_zone() - Register a power zone
* @power_zone: Pointer to client allocated memory for the power zone structure
* storage. If this is NULL, powercap framework will allocate
* memory and own it. Advantage of this parameter is that client
* can embed this data in its data structures and allocate in a
* single call, preventing multiple allocations.
* @control_type: A control_type instance under which this zone operates.
* @name: A name for this zone.
* @parent: A pointer to the parent power zone instance if any or NULL
* @ops: Pointer to zone operation callback structure.
* @no_constraints: Number of constraints for this zone
* @const_ops: Pointer to constraint callback structure
*
* Register a power zone under a given control type. A power zone must register
* a pointer to a structure representing zone callbacks.
* A power zone can be located under a parent power zone, in which case @parent
* should point to it. Otherwise, if @parent is NULL, the new power zone will
* be located directly under the given control type
* For each power zone there may be a number of constraints that appear in the
* sysfs under that zone as attributes with unique numeric IDs.
* Returns pointer to the power_zone on success.
*/
struct powercap_zone *powercap_register_zone(
struct powercap_zone *power_zone,
struct powercap_control_type *control_type,
const char *name,
struct powercap_zone *parent,
const struct powercap_zone_ops *ops,
int nr_constraints,
struct powercap_zone_constraint_ops *const_ops);
/**
* powercap_unregister_zone() - Unregister a zone device
* @control_type: A pointer to the valid instance of a control_type.
* @power_zone: A pointer to the valid zone instance for a control_type
*
* Used to unregister a zone device for a control_type. Caller should
* make sure that children for this zone are unregistered first.
*/
int powercap_unregister_zone(struct powercap_control_type *control_type,
struct powercap_zone *power_zone);
#endif