diff options
Diffstat (limited to 'drivers/powercap')
| -rw-r--r-- | drivers/powercap/Kconfig | 19 | ||||
| -rw-r--r-- | drivers/powercap/Makefile | 1 | ||||
| -rw-r--r-- | drivers/powercap/powercap_sys.c | 683 |
3 files changed, 703 insertions, 0 deletions
diff --git a/drivers/powercap/Kconfig b/drivers/powercap/Kconfig new file mode 100644 index 000000000000..a37055eb5ebc --- /dev/null +++ b/drivers/powercap/Kconfig @@ -0,0 +1,19 @@ +# +# 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 diff --git a/drivers/powercap/Makefile b/drivers/powercap/Makefile new file mode 100644 index 000000000000..6defbc8dc4bf --- /dev/null +++ b/drivers/powercap/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_POWERCAP) += powercap_sys.o diff --git a/drivers/powercap/powercap_sys.c b/drivers/powercap/powercap_sys.c new file mode 100644 index 000000000000..c22fa4c78eaa --- /dev/null +++ b/drivers/powercap/powercap_sys.c @@ -0,0 +1,683 @@ +/* + * 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"); |