Commit 75d2364e authored by Srinivas Pandruvada's avatar Srinivas Pandruvada Committed by Rafael J. Wysocki

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: default avatarSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: default avatarJacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent e23feb16
#
# Generic power capping sysfs interface configuration
#
menuconfig POWERCAP
bool "Generic powercap sysfs driver"
help
The power capping sysfs interface allows kernel subsystems to expose power
capping settings to user space in a consistent way. Usually, it consists
of multiple control types that determine which settings may be exposed and
power zones representing parts of the system that can be subject to power
capping.
If you want this code to be compiled in, say Y here.
if POWERCAP
# Client driver configurations go here.
endif
obj-$(CONFIG_POWERCAP) += powercap_sys.o
/*
* Power capping class
* 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.
*
*/
#include <linux/module.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/powercap.h>
#define to_powercap_zone(n) container_of(n, struct powercap_zone, dev)
#define to_powercap_control_type(n) \
container_of(n, struct powercap_control_type, dev)
/* Power zone show function */
#define define_power_zone_show(_attr) \
static ssize_t _attr##_show(struct device *dev, \
struct device_attribute *dev_attr,\
char *buf) \
{ \
u64 value; \
ssize_t len = -EINVAL; \
struct powercap_zone *power_zone = to_powercap_zone(dev); \
\
if (power_zone->ops->get_##_attr) { \
if (!power_zone->ops->get_##_attr(power_zone, &value)) \
len = sprintf(buf, "%lld\n", value); \
} \
\
return len; \
}
/* The only meaningful input is 0 (reset), others are silently ignored */
#define define_power_zone_store(_attr) \
static ssize_t _attr##_store(struct device *dev,\
struct device_attribute *dev_attr, \
const char *buf, size_t count) \
{ \
int err; \
struct powercap_zone *power_zone = to_powercap_zone(dev); \
u64 value; \
\
err = kstrtoull(buf, 10, &value); \
if (err) \
return -EINVAL; \
if (value) \
return count; \
if (power_zone->ops->reset_##_attr) { \
if (!power_zone->ops->reset_##_attr(power_zone)) \
return count; \
} \
\
return -EINVAL; \
}
/* Power zone constraint show function */
#define define_power_zone_constraint_show(_attr) \
static ssize_t show_constraint_##_attr(struct device *dev, \
struct device_attribute *dev_attr,\
char *buf) \
{ \
u64 value; \
ssize_t len = -ENODATA; \
struct powercap_zone *power_zone = to_powercap_zone(dev); \
int id; \
struct powercap_zone_constraint *pconst;\
\
if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
return -EINVAL; \
if (id >= power_zone->const_id_cnt) \
return -EINVAL; \
pconst = &power_zone->constraints[id]; \
if (pconst && pconst->ops && pconst->ops->get_##_attr) { \
if (!pconst->ops->get_##_attr(power_zone, id, &value)) \
len = sprintf(buf, "%lld\n", value); \
} \
\
return len; \
}
/* Power zone constraint store function */
#define define_power_zone_constraint_store(_attr) \
static ssize_t store_constraint_##_attr(struct device *dev,\
struct device_attribute *dev_attr, \
const char *buf, size_t count) \
{ \
int err; \
u64 value; \
struct powercap_zone *power_zone = to_powercap_zone(dev); \
int id; \
struct powercap_zone_constraint *pconst;\
\
if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \
return -EINVAL; \
if (id >= power_zone->const_id_cnt) \
return -EINVAL; \
pconst = &power_zone->constraints[id]; \
err = kstrtoull(buf, 10, &value); \
if (err) \
return -EINVAL; \
if (pconst && pconst->ops && pconst->ops->set_##_attr) { \
if (!pconst->ops->set_##_attr(power_zone, id, value)) \
return count; \
} \
\
return -ENODATA; \
}
/* Power zone information callbacks */
define_power_zone_show(power_uw);
define_power_zone_show(max_power_range_uw);
define_power_zone_show(energy_uj);
define_power_zone_store(energy_uj);
define_power_zone_show(max_energy_range_uj);
/* Power zone attributes */
static DEVICE_ATTR_RO(max_power_range_uw);
static DEVICE_ATTR_RO(power_uw);
static DEVICE_ATTR_RO(max_energy_range_uj);
static DEVICE_ATTR_RW(energy_uj);
/* Power zone constraint attributes callbacks */
define_power_zone_constraint_show(power_limit_uw);
define_power_zone_constraint_store(power_limit_uw);
define_power_zone_constraint_show(time_window_us);
define_power_zone_constraint_store(time_window_us);
define_power_zone_constraint_show(max_power_uw);
define_power_zone_constraint_show(min_power_uw);
define_power_zone_constraint_show(max_time_window_us);
define_power_zone_constraint_show(min_time_window_us);
/* For one time seeding of constraint device attributes */
struct powercap_constraint_attr {
struct device_attribute power_limit_attr;
struct device_attribute time_window_attr;
struct device_attribute max_power_attr;
struct device_attribute min_power_attr;
struct device_attribute max_time_window_attr;
struct device_attribute min_time_window_attr;
struct device_attribute name_attr;
};
static struct powercap_constraint_attr
constraint_attrs[MAX_CONSTRAINTS_PER_ZONE];
/* A list of powercap control_types */
static LIST_HEAD(powercap_cntrl_list);
/* Mutex to protect list of powercap control_types */
static DEFINE_MUTEX(powercap_cntrl_list_lock);
#define POWERCAP_CONSTRAINT_NAME_LEN 30 /* Some limit to avoid overflow */
static ssize_t show_constraint_name(struct device *dev,
struct device_attribute *dev_attr,
char *buf)
{
const char *name;
struct powercap_zone *power_zone = to_powercap_zone(dev);
int id;
ssize_t len = -ENODATA;
struct powercap_zone_constraint *pconst;
if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id))
return -EINVAL;
if (id >= power_zone->const_id_cnt)
return -EINVAL;
pconst = &power_zone->constraints[id];
if (pconst && pconst->ops && pconst->ops->get_name) {
name = pconst->ops->get_name(power_zone, id);
if (name) {
snprintf(buf, POWERCAP_CONSTRAINT_NAME_LEN,
"%s\n", name);
buf[POWERCAP_CONSTRAINT_NAME_LEN] = '\0';
len = strlen(buf);
}
}
return len;
}
static int create_constraint_attribute(int id, const char *name,
int mode,
struct device_attribute *dev_attr,
ssize_t (*show)(struct device *,
struct device_attribute *, char *),
ssize_t (*store)(struct device *,
struct device_attribute *,
const char *, size_t)
)
{
dev_attr->attr.name = kasprintf(GFP_KERNEL, "constraint_%d_%s",
id, name);
if (!dev_attr->attr.name)
return -ENOMEM;
dev_attr->attr.mode = mode;
dev_attr->show = show;
dev_attr->store = store;
return 0;
}
static void free_constraint_attributes(void)
{
int i;
for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
kfree(constraint_attrs[i].power_limit_attr.attr.name);
kfree(constraint_attrs[i].time_window_attr.attr.name);
kfree(constraint_attrs[i].name_attr.attr.name);
kfree(constraint_attrs[i].max_power_attr.attr.name);
kfree(constraint_attrs[i].min_power_attr.attr.name);
kfree(constraint_attrs[i].max_time_window_attr.attr.name);
kfree(constraint_attrs[i].min_time_window_attr.attr.name);
}
}
static int seed_constraint_attributes(void)
{
int i;
int ret;
for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) {
ret = create_constraint_attribute(i, "power_limit_uw",
S_IWUSR | S_IRUGO,
&constraint_attrs[i].power_limit_attr,
show_constraint_power_limit_uw,
store_constraint_power_limit_uw);
if (ret)
goto err_alloc;
ret = create_constraint_attribute(i, "time_window_us",
S_IWUSR | S_IRUGO,
&constraint_attrs[i].time_window_attr,
show_constraint_time_window_us,
store_constraint_time_window_us);
if (ret)
goto err_alloc;
ret = create_constraint_attribute(i, "name", S_IRUGO,
&constraint_attrs[i].name_attr,
show_constraint_name,
NULL);
if (ret)
goto err_alloc;
ret = create_constraint_attribute(i, "max_power_uw", S_IRUGO,
&constraint_attrs[i].max_power_attr,
show_constraint_max_power_uw,
NULL);
if (ret)
goto err_alloc;
ret = create_constraint_attribute(i, "min_power_uw", S_IRUGO,
&constraint_attrs[i].min_power_attr,
show_constraint_min_power_uw,
NULL);
if (ret)
goto err_alloc;
ret = create_constraint_attribute(i, "max_time_window_us",
S_IRUGO,
&constraint_attrs[i].max_time_window_attr,
show_constraint_max_time_window_us,
NULL);
if (ret)
goto err_alloc;
ret = create_constraint_attribute(i, "min_time_window_us",
S_IRUGO,
&constraint_attrs[i].min_time_window_attr,
show_constraint_min_time_window_us,
NULL);
if (ret)
goto err_alloc;
}
return 0;
err_alloc:
free_constraint_attributes();
return ret;
}
static int create_constraints(struct powercap_zone *power_zone,
int nr_constraints,
struct powercap_zone_constraint_ops *const_ops)
{
int i;
int ret = 0;
int count;
struct powercap_zone_constraint *pconst;
if (!power_zone || !const_ops || !const_ops->get_power_limit_uw ||
!const_ops->set_power_limit_uw ||
!const_ops->get_time_window_us ||
!const_ops->set_time_window_us)
return -EINVAL;
count = power_zone->zone_attr_count;
for (i = 0; i < nr_constraints; ++i) {
pconst = &power_zone->constraints[i];
pconst->ops = const_ops;
pconst->id = power_zone->const_id_cnt;
power_zone->const_id_cnt++;
power_zone->zone_dev_attrs[count++] =
&constraint_attrs[i].power_limit_attr.attr;
power_zone->zone_dev_attrs[count++] =
&constraint_attrs[i].time_window_attr.attr;
if (pconst->ops->get_name)
power_zone->zone_dev_attrs[count++] =
&constraint_attrs[i].name_attr.attr;
if (pconst->ops->get_max_power_uw)
power_zone->zone_dev_attrs[count++] =
&constraint_attrs[i].max_power_attr.attr;
if (pconst->ops->get_min_power_uw)
power_zone->zone_dev_attrs[count++] =
&constraint_attrs[i].min_power_attr.attr;
if (pconst->ops->get_max_time_window_us)
power_zone->zone_dev_attrs[count++] =
&constraint_attrs[i].max_time_window_attr.attr;
if (pconst->ops->get_min_time_window_us)
power_zone->zone_dev_attrs[count++] =
&constraint_attrs[i].min_time_window_attr.attr;
}
power_zone->zone_attr_count = count;
return ret;
}
static bool control_type_valid(void *control_type)
{
struct powercap_control_type *pos = NULL;
bool found = false;
mutex_lock(&powercap_cntrl_list_lock);
list_for_each_entry(pos, &powercap_cntrl_list, node) {
if (pos == control_type) {
found = true;
break;
}
}
mutex_unlock(&powercap_cntrl_list_lock);
return found;
}
static ssize_t name_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct powercap_zone *power_zone = to_powercap_zone(dev);
return sprintf(buf, "%s\n", power_zone->name);
}
static DEVICE_ATTR_RO(name);
/* Create zone and attributes in sysfs */
static void create_power_zone_common_attributes(
struct powercap_zone *power_zone)
{
int count = 0;
power_zone->zone_dev_attrs[count++] = &dev_attr_name.attr;
if (power_zone->ops->get_max_energy_range_uj)
power_zone->zone_dev_attrs[count++] =
&dev_attr_max_energy_range_uj.attr;
if (power_zone->ops->get_energy_uj)
power_zone->zone_dev_attrs[count++] =
&dev_attr_energy_uj.attr;
if (power_zone->ops->get_power_uw)
power_zone->zone_dev_attrs[count++] =
&dev_attr_power_uw.attr;
if (power_zone->ops->get_max_power_range_uw)
power_zone->zone_dev_attrs[count++] =
&dev_attr_max_power_range_uw.attr;
power_zone->zone_dev_attrs[count] = NULL;
power_zone->zone_attr_count = count;
}
static void powercap_release(struct device *dev)
{
bool allocated;
if (dev->parent) {
struct powercap_zone *power_zone = to_powercap_zone(dev);
/* Store flag as the release() may free memory */
allocated = power_zone->allocated;
/* Remove id from parent idr struct */
idr_remove(power_zone->parent_idr, power_zone->id);
/* Destroy idrs allocated for this zone */
idr_destroy(&power_zone->idr);
kfree(power_zone->name);
kfree(power_zone->zone_dev_attrs);
kfree(power_zone->constraints);
if (power_zone->ops->release)
power_zone->ops->release(power_zone);
if (allocated)
kfree(power_zone);
} else {
struct powercap_control_type *control_type =
to_powercap_control_type(dev);
/* Store flag as the release() may free memory */
allocated = control_type->allocated;
idr_destroy(&control_type->idr);
mutex_destroy(&control_type->lock);
if (control_type->ops && control_type->ops->release)
control_type->ops->release(control_type);
if (allocated)
kfree(control_type);
}
}
static ssize_t enabled_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
bool mode = true;
/* Default is enabled */
if (dev->parent) {
struct powercap_zone *power_zone = to_powercap_zone(dev);
if (power_zone->ops->get_enable)
if (power_zone->ops->get_enable(power_zone, &mode))
mode = false;
} else {
struct powercap_control_type *control_type =
to_powercap_control_type(dev);
if (control_type->ops && control_type->ops->get_enable)
if (control_type->ops->get_enable(control_type, &mode))
mode = false;
}
return sprintf(buf, "%d\n", mode);
}
static ssize_t enabled_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
bool mode;
if (strtobool(buf, &mode))
return -EINVAL;
if (dev->parent) {
struct powercap_zone *power_zone = to_powercap_zone(dev);
if (power_zone->ops->set_enable)
if (!power_zone->ops->set_enable(power_zone, mode))
return len;
} else {
struct powercap_control_type *control_type =
to_powercap_control_type(dev);
if (control_type->ops && control_type->ops->set_enable)
if (!control_type->ops->set_enable(control_type, mode))
return len;
}
return -ENOSYS;
}
static struct device_attribute powercap_def_attrs[] = {
__ATTR(enabled, S_IWUSR | S_IRUGO, enabled_show,
enabled_store),
__ATTR_NULL
};
static struct class powercap_class = {
.name = "powercap",
.dev_release = powercap_release,
.dev_attrs = powercap_def_attrs,
};
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)
{
int result;
int nr_attrs;
if (!name || !control_type || !ops ||
nr_constraints > MAX_CONSTRAINTS_PER_ZONE ||
(!ops->get_energy_uj && !ops->get_power_uw) ||
!control_type_valid(control_type))
return ERR_PTR(-EINVAL);
if (power_zone) {
if (!ops->release)
return ERR_PTR(-EINVAL);
memset(power_zone, 0, sizeof(*power_zone));
} else {
power_zone = kzalloc(sizeof(*power_zone), GFP_KERNEL);
if (!power_zone)
return ERR_PTR(-ENOMEM);
power_zone->allocated = true;
}
power_zone->ops = ops;
power_zone->control_type_inst = control_type;
if (!parent) {
power_zone->dev.parent = &control_type->dev;
power_zone->parent_idr = &control_type->idr;
} else {
power_zone->dev.parent = &parent->dev;
power_zone->parent_idr = &parent->idr;
}
power_zone->dev.class = &powercap_class;
mutex_lock(&control_type->lock);
/* Using idr to get the unique id */
result = idr_alloc(power_zone->parent_idr, NULL, 0, 0, GFP_KERNEL);
if (result < 0)
goto err_idr_alloc;
power_zone->id = result;
idr_init(&power_zone->idr);
power_zone->name = kstrdup(name, GFP_KERNEL);
if (!power_zone->name)
goto err_name_alloc;
dev_set_name(&power_zone->dev, "%s:%x",
dev_name(power_zone->dev.parent),
power_zone->id);
power_zone->constraints = kzalloc(sizeof(*power_zone->constraints) *
nr_constraints, GFP_KERNEL);
if (!power_zone->constraints)
goto err_const_alloc;
nr_attrs = nr_constraints * POWERCAP_CONSTRAINTS_ATTRS +
POWERCAP_ZONE_MAX_ATTRS + 1;
power_zone->zone_dev_attrs = kzalloc(sizeof(void *) *
nr_attrs, GFP_KERNEL);
if (!power_zone->zone_dev_attrs)
goto err_attr_alloc;
create_power_zone_common_attributes(power_zone);
result = create_constraints(power_zone, nr_constraints, const_ops);
if (result)
goto err_dev_ret;
power_zone->zone_dev_attrs[power_zone->zone_attr_count] = NULL;
power_zone->dev_zone_attr_group.attrs = power_zone->zone_dev_attrs;
power_zone->dev_attr_groups[0] = &power_zone->dev_zone_attr_group;
power_zone->dev_attr_groups[1] = NULL;
power_zone->dev.groups = power_zone->dev_attr_groups;
result = device_register(&power_zone->dev);
if (result)
goto err_dev_ret;
control_type->nr_zones++;
mutex_unlock(&control_type->lock);
return power_zone;
err_dev_ret:
kfree(power_zone->zone_dev_attrs);
err_attr_alloc:
kfree(power_zone->constraints);
err_const_alloc:
kfree(power_zone->name);
err_name_alloc:
idr_remove(power_zone->parent_idr, power_zone->id);
err_idr_alloc:
if (power_zone->allocated)
kfree(power_zone);
mutex_unlock(&control_type->lock);
return ERR_PTR(result);
}
EXPORT_SYMBOL_GPL(powercap_register_zone);
int powercap_unregister_zone(struct powercap_control_type *control_type,
struct powercap_zone *power_zone)
{
if (!power_zone || !control_type)
return -EINVAL;
mutex_lock(&control_type->lock);
control_type->nr_zones--;
mutex_unlock(&control_type->lock);
device_unregister(&power_zone->dev);
return 0;
}
EXPORT_SYMBOL_GPL(powercap_unregister_zone);
struct powercap_control_type *powercap_register_control_type(
struct powercap_control_type *control_type,
const char *name,
const struct powercap_control_type_ops *ops)
{
int result;
if (!name)
return ERR_PTR(-EINVAL);
if (control_type) {
if (!ops || !ops->release)
return ERR_PTR(-EINVAL);
memset(control_type, 0, sizeof(*control_type));
} else {
control_type = kzalloc(sizeof(*control_type), GFP_KERNEL);
if (!control_type)
return ERR_PTR(-ENOMEM);
control_type->allocated = true;
}
mutex_init(&control_type->lock);
control_type->ops = ops;
INIT_LIST_HEAD(&control_type->node);
control_type->dev.class = &powercap_class;
dev_set_name(&control_type->dev, name);
result = device_register(&control_type->dev);
if (result) {
if (control_type->allocated)
kfree(control_type);
return ERR_PTR(result);
}
idr_init(&control_type->idr);
mutex_lock(&powercap_cntrl_list_lock);
list_add_tail(&control_type->node, &powercap_cntrl_list);
mutex_unlock(&powercap_cntrl_list_lock);
return control_type;
}
EXPORT_SYMBOL_GPL(powercap_register_control_type);
int powercap_unregister_control_type(struct powercap_control_type *control_type)
{
struct powercap_control_type *pos = NULL;
if (control_type->nr_zones) {
dev_err(&control_type->dev, "Zones of this type still not freed\n");
return -EINVAL;
}
mutex_lock(&powercap_cntrl_list_lock);
list_for_each_entry(pos, &powercap_cntrl_list, node) {
if (pos == control_type) {
list_del(&control_type->node);
mutex_unlock(&powercap_cntrl_list_lock);
device_unregister(&control_type->dev);
return 0;
}
}
mutex_unlock(&powercap_cntrl_list_lock);
return -ENODEV;
}
EXPORT_SYMBOL_GPL(powercap_unregister_control_type);
static int __init powercap_init(void)
{
int result = 0;
result = seed_constraint_attributes();
if (result)
return result;
result = class_register(&powercap_class);
return result;
}
device_initcall(powercap_init);
MODULE_DESCRIPTION("PowerCap sysfs Driver");
MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
MODULE_LICENSE("GPL v2");
/*
* 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
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