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-rw-r--r--drivers/powercap/Kconfig8
-rw-r--r--drivers/powercap/Makefile1
-rw-r--r--drivers/powercap/dtpm.c333
-rw-r--r--drivers/powercap/dtpm_cpu.c55
-rw-r--r--drivers/powercap/dtpm_devfreq.c203
-rw-r--r--drivers/powercap/dtpm_subsys.h22
6 files changed, 542 insertions, 80 deletions
diff --git a/drivers/powercap/Kconfig b/drivers/powercap/Kconfig
index 8242e8c5ed77..515e3ceb3393 100644
--- a/drivers/powercap/Kconfig
+++ b/drivers/powercap/Kconfig
@@ -46,6 +46,7 @@ config IDLE_INJECT
config DTPM
bool "Power capping for Dynamic Thermal Power Management (EXPERIMENTAL)"
+ depends on OF
help
This enables support for the power capping for the dynamic
thermal power management userspace engine.
@@ -56,4 +57,11 @@ config DTPM_CPU
help
This enables support for CPU power limitation based on
energy model.
+
+config DTPM_DEVFREQ
+ bool "Add device power capping based on the energy model"
+ depends on DTPM && ENERGY_MODEL
+ help
+ This enables support for device power limitation based on
+ energy model.
endif
diff --git a/drivers/powercap/Makefile b/drivers/powercap/Makefile
index fabcf388a8d3..494617cdad88 100644
--- a/drivers/powercap/Makefile
+++ b/drivers/powercap/Makefile
@@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_DTPM) += dtpm.o
obj-$(CONFIG_DTPM_CPU) += dtpm_cpu.o
+obj-$(CONFIG_DTPM_DEVFREQ) += dtpm_devfreq.o
obj-$(CONFIG_POWERCAP) += powercap_sys.o
obj-$(CONFIG_INTEL_RAPL_CORE) += intel_rapl_common.o
obj-$(CONFIG_INTEL_RAPL) += intel_rapl_msr.o
diff --git a/drivers/powercap/dtpm.c b/drivers/powercap/dtpm.c
index 8cb45f2d3d78..ce920f17f45f 100644
--- a/drivers/powercap/dtpm.c
+++ b/drivers/powercap/dtpm.c
@@ -23,6 +23,9 @@
#include <linux/powercap.h>
#include <linux/slab.h>
#include <linux/mutex.h>
+#include <linux/of.h>
+
+#include "dtpm_subsys.h"
#define DTPM_POWER_LIMIT_FLAG 0
@@ -48,9 +51,7 @@ static int get_max_power_range_uw(struct powercap_zone *pcz, u64 *max_power_uw)
{
struct dtpm *dtpm = to_dtpm(pcz);
- mutex_lock(&dtpm_lock);
*max_power_uw = dtpm->power_max - dtpm->power_min;
- mutex_unlock(&dtpm_lock);
return 0;
}
@@ -80,14 +81,7 @@ static int __get_power_uw(struct dtpm *dtpm, u64 *power_uw)
static int get_power_uw(struct powercap_zone *pcz, u64 *power_uw)
{
- struct dtpm *dtpm = to_dtpm(pcz);
- int ret;
-
- mutex_lock(&dtpm_lock);
- ret = __get_power_uw(dtpm, power_uw);
- mutex_unlock(&dtpm_lock);
-
- return ret;
+ return __get_power_uw(to_dtpm(pcz), power_uw);
}
static void __dtpm_rebalance_weight(struct dtpm *dtpm)
@@ -130,7 +124,16 @@ static void __dtpm_add_power(struct dtpm *dtpm)
}
}
-static int __dtpm_update_power(struct dtpm *dtpm)
+/**
+ * dtpm_update_power - Update the power on the dtpm
+ * @dtpm: a pointer to a dtpm structure to update
+ *
+ * Function to update the power values of the dtpm node specified in
+ * parameter. These new values will be propagated to the tree.
+ *
+ * Return: zero on success, -EINVAL if the values are inconsistent
+ */
+int dtpm_update_power(struct dtpm *dtpm)
{
int ret;
@@ -153,26 +156,6 @@ static int __dtpm_update_power(struct dtpm *dtpm)
}
/**
- * dtpm_update_power - Update the power on the dtpm
- * @dtpm: a pointer to a dtpm structure to update
- *
- * Function to update the power values of the dtpm node specified in
- * parameter. These new values will be propagated to the tree.
- *
- * Return: zero on success, -EINVAL if the values are inconsistent
- */
-int dtpm_update_power(struct dtpm *dtpm)
-{
- int ret;
-
- mutex_lock(&dtpm_lock);
- ret = __dtpm_update_power(dtpm);
- mutex_unlock(&dtpm_lock);
-
- return ret;
-}
-
-/**
* dtpm_release_zone - Cleanup when the node is released
* @pcz: a pointer to a powercap_zone structure
*
@@ -188,48 +171,28 @@ int dtpm_release_zone(struct powercap_zone *pcz)
struct dtpm *dtpm = to_dtpm(pcz);
struct dtpm *parent = dtpm->parent;
- mutex_lock(&dtpm_lock);
-
- if (!list_empty(&dtpm->children)) {
- mutex_unlock(&dtpm_lock);
+ if (!list_empty(&dtpm->children))
return -EBUSY;
- }
if (parent)
list_del(&dtpm->sibling);
__dtpm_sub_power(dtpm);
- mutex_unlock(&dtpm_lock);
-
if (dtpm->ops)
dtpm->ops->release(dtpm);
+ else
+ kfree(dtpm);
- if (root == dtpm)
- root = NULL;
-
- kfree(dtpm);
-
- return 0;
-}
-
-static int __get_power_limit_uw(struct dtpm *dtpm, int cid, u64 *power_limit)
-{
- *power_limit = dtpm->power_limit;
return 0;
}
static int get_power_limit_uw(struct powercap_zone *pcz,
int cid, u64 *power_limit)
{
- struct dtpm *dtpm = to_dtpm(pcz);
- int ret;
-
- mutex_lock(&dtpm_lock);
- ret = __get_power_limit_uw(dtpm, cid, power_limit);
- mutex_unlock(&dtpm_lock);
-
- return ret;
+ *power_limit = to_dtpm(pcz)->power_limit;
+
+ return 0;
}
/*
@@ -289,7 +252,7 @@ static int __set_power_limit_uw(struct dtpm *dtpm, int cid, u64 power_limit)
ret = __set_power_limit_uw(child, cid, power);
if (!ret)
- ret = __get_power_limit_uw(child, cid, &power);
+ ret = get_power_limit_uw(&child->zone, cid, &power);
if (ret)
break;
@@ -307,8 +270,6 @@ static int set_power_limit_uw(struct powercap_zone *pcz,
struct dtpm *dtpm = to_dtpm(pcz);
int ret;
- mutex_lock(&dtpm_lock);
-
/*
* Don't allow values outside of the power range previously
* set when initializing the power numbers.
@@ -320,8 +281,6 @@ static int set_power_limit_uw(struct powercap_zone *pcz,
pr_debug("%s: power limit: %llu uW, power max: %llu uW\n",
dtpm->zone.name, dtpm->power_limit, dtpm->power_max);
- mutex_unlock(&dtpm_lock);
-
return ret;
}
@@ -332,11 +291,7 @@ static const char *get_constraint_name(struct powercap_zone *pcz, int cid)
static int get_max_power_uw(struct powercap_zone *pcz, int id, u64 *max_power)
{
- struct dtpm *dtpm = to_dtpm(pcz);
-
- mutex_lock(&dtpm_lock);
- *max_power = dtpm->power_max;
- mutex_unlock(&dtpm_lock);
+ *max_power = to_dtpm(pcz)->power_max;
return 0;
}
@@ -439,8 +394,6 @@ int dtpm_register(const char *name, struct dtpm *dtpm, struct dtpm *parent)
if (IS_ERR(pcz))
return PTR_ERR(pcz);
- mutex_lock(&dtpm_lock);
-
if (parent) {
list_add_tail(&dtpm->sibling, &parent->children);
dtpm->parent = parent;
@@ -456,19 +409,253 @@ int dtpm_register(const char *name, struct dtpm *dtpm, struct dtpm *parent)
pr_debug("Registered dtpm node '%s' / %llu-%llu uW, \n",
dtpm->zone.name, dtpm->power_min, dtpm->power_max);
- mutex_unlock(&dtpm_lock);
+ return 0;
+}
+
+static struct dtpm *dtpm_setup_virtual(const struct dtpm_node *hierarchy,
+ struct dtpm *parent)
+{
+ struct dtpm *dtpm;
+ int ret;
+
+ dtpm = kzalloc(sizeof(*dtpm), GFP_KERNEL);
+ if (!dtpm)
+ return ERR_PTR(-ENOMEM);
+ dtpm_init(dtpm, NULL);
+
+ ret = dtpm_register(hierarchy->name, dtpm, parent);
+ if (ret) {
+ pr_err("Failed to register dtpm node '%s': %d\n",
+ hierarchy->name, ret);
+ kfree(dtpm);
+ return ERR_PTR(ret);
+ }
+
+ return dtpm;
+}
+
+static struct dtpm *dtpm_setup_dt(const struct dtpm_node *hierarchy,
+ struct dtpm *parent)
+{
+ struct device_node *np;
+ int i, ret;
+
+ np = of_find_node_by_path(hierarchy->name);
+ if (!np) {
+ pr_err("Failed to find '%s'\n", hierarchy->name);
+ return ERR_PTR(-ENXIO);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(dtpm_subsys); i++) {
+
+ if (!dtpm_subsys[i]->setup)
+ continue;
+
+ ret = dtpm_subsys[i]->setup(parent, np);
+ if (ret) {
+ pr_err("Failed to setup '%s': %d\n", dtpm_subsys[i]->name, ret);
+ of_node_put(np);
+ return ERR_PTR(ret);
+ }
+ }
+
+ of_node_put(np);
+
+ /*
+ * By returning a NULL pointer, we let know the caller there
+ * is no child for us as we are a leaf of the tree
+ */
+ return NULL;
+}
+
+typedef struct dtpm * (*dtpm_node_callback_t)(const struct dtpm_node *, struct dtpm *);
+
+static dtpm_node_callback_t dtpm_node_callback[] = {
+ [DTPM_NODE_VIRTUAL] = dtpm_setup_virtual,
+ [DTPM_NODE_DT] = dtpm_setup_dt,
+};
+
+static int dtpm_for_each_child(const struct dtpm_node *hierarchy,
+ const struct dtpm_node *it, struct dtpm *parent)
+{
+ struct dtpm *dtpm;
+ int i, ret;
+
+ for (i = 0; hierarchy[i].name; i++) {
+
+ if (hierarchy[i].parent != it)
+ continue;
+
+ dtpm = dtpm_node_callback[hierarchy[i].type](&hierarchy[i], parent);
+
+ /*
+ * A NULL pointer means there is no children, hence we
+ * continue without going deeper in the recursivity.
+ */
+ if (!dtpm)
+ continue;
+
+ /*
+ * There are multiple reasons why the callback could
+ * fail. The generic glue is abstracting the backend
+ * and therefore it is not possible to report back or
+ * take a decision based on the error. In any case,
+ * if this call fails, it is not critical in the
+ * hierarchy creation, we can assume the underlying
+ * service is not found, so we continue without this
+ * branch in the tree but with a warning to log the
+ * information the node was not created.
+ */
+ if (IS_ERR(dtpm)) {
+ pr_warn("Failed to create '%s' in the hierarchy\n",
+ hierarchy[i].name);
+ continue;
+ }
+
+ ret = dtpm_for_each_child(hierarchy, &hierarchy[i], dtpm);
+ if (ret)
+ return ret;
+ }
return 0;
}
-static int __init init_dtpm(void)
+/**
+ * dtpm_create_hierarchy - Create the dtpm hierarchy
+ * @hierarchy: An array of struct dtpm_node describing the hierarchy
+ *
+ * The function is called by the platform specific code with the
+ * description of the different node in the hierarchy. It creates the
+ * tree in the sysfs filesystem under the powercap dtpm entry.
+ *
+ * The expected tree has the format:
+ *
+ * struct dtpm_node hierarchy[] = {
+ * [0] { .name = "topmost", type = DTPM_NODE_VIRTUAL },
+ * [1] { .name = "package", .type = DTPM_NODE_VIRTUAL, .parent = &hierarchy[0] },
+ * [2] { .name = "/cpus/cpu0", .type = DTPM_NODE_DT, .parent = &hierarchy[1] },
+ * [3] { .name = "/cpus/cpu1", .type = DTPM_NODE_DT, .parent = &hierarchy[1] },
+ * [4] { .name = "/cpus/cpu2", .type = DTPM_NODE_DT, .parent = &hierarchy[1] },
+ * [5] { .name = "/cpus/cpu3", .type = DTPM_NODE_DT, .parent = &hierarchy[1] },
+ * [6] { }
+ * };
+ *
+ * The last element is always an empty one and marks the end of the
+ * array.
+ *
+ * Return: zero on success, a negative value in case of error. Errors
+ * are reported back from the underlying functions.
+ */
+int dtpm_create_hierarchy(struct of_device_id *dtpm_match_table)
{
+ const struct of_device_id *match;
+ const struct dtpm_node *hierarchy;
+ struct device_node *np;
+ int i, ret;
+
+ mutex_lock(&dtpm_lock);
+
+ if (pct) {
+ ret = -EBUSY;
+ goto out_unlock;
+ }
+
pct = powercap_register_control_type(NULL, "dtpm", NULL);
if (IS_ERR(pct)) {
pr_err("Failed to register control type\n");
- return PTR_ERR(pct);
+ ret = PTR_ERR(pct);
+ goto out_pct;
}
+ ret = -ENODEV;
+ np = of_find_node_by_path("/");
+ if (!np)
+ goto out_err;
+
+ match = of_match_node(dtpm_match_table, np);
+
+ of_node_put(np);
+
+ if (!match)
+ goto out_err;
+
+ hierarchy = match->data;
+ if (!hierarchy) {
+ ret = -EFAULT;
+ goto out_err;
+ }
+
+ ret = dtpm_for_each_child(hierarchy, NULL, NULL);
+ if (ret)
+ goto out_err;
+
+ for (i = 0; i < ARRAY_SIZE(dtpm_subsys); i++) {
+
+ if (!dtpm_subsys[i]->init)
+ continue;
+
+ ret = dtpm_subsys[i]->init();
+ if (ret)
+ pr_info("Failed to initialize '%s': %d",
+ dtpm_subsys[i]->name, ret);
+ }
+
+ mutex_unlock(&dtpm_lock);
+
return 0;
+
+out_err:
+ powercap_unregister_control_type(pct);
+out_pct:
+ pct = NULL;
+out_unlock:
+ mutex_unlock(&dtpm_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dtpm_create_hierarchy);
+
+static void __dtpm_destroy_hierarchy(struct dtpm *dtpm)
+{
+ struct dtpm *child, *aux;
+
+ list_for_each_entry_safe(child, aux, &dtpm->children, sibling)
+ __dtpm_destroy_hierarchy(child);
+
+ /*
+ * At this point, we know all children were removed from the
+ * recursive call before
+ */
+ dtpm_unregister(dtpm);
+}
+
+void dtpm_destroy_hierarchy(void)
+{
+ int i;
+
+ mutex_lock(&dtpm_lock);
+
+ if (!pct)
+ goto out_unlock;
+
+ __dtpm_destroy_hierarchy(root);
+
+
+ for (i = 0; i < ARRAY_SIZE(dtpm_subsys); i++) {
+
+ if (!dtpm_subsys[i]->exit)
+ continue;
+
+ dtpm_subsys[i]->exit();
+ }
+
+ powercap_unregister_control_type(pct);
+
+ pct = NULL;
+
+ root = NULL;
+
+out_unlock:
+ mutex_unlock(&dtpm_lock);
}
-late_initcall(init_dtpm);
+EXPORT_SYMBOL_GPL(dtpm_destroy_hierarchy);
diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c
index b740866b228d..bca2f912d349 100644
--- a/drivers/powercap/dtpm_cpu.c
+++ b/drivers/powercap/dtpm_cpu.c
@@ -21,6 +21,7 @@
#include <linux/cpuhotplug.h>
#include <linux/dtpm.h>
#include <linux/energy_model.h>
+#include <linux/of.h>
#include <linux/pm_qos.h>
#include <linux/slab.h>
#include <linux/units.h>
@@ -150,10 +151,17 @@ static int update_pd_power_uw(struct dtpm *dtpm)
static void pd_release(struct dtpm *dtpm)
{
struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm);
+ struct cpufreq_policy *policy;
if (freq_qos_request_active(&dtpm_cpu->qos_req))
freq_qos_remove_request(&dtpm_cpu->qos_req);
+ policy = cpufreq_cpu_get(dtpm_cpu->cpu);
+ if (policy) {
+ for_each_cpu(dtpm_cpu->cpu, policy->related_cpus)
+ per_cpu(dtpm_per_cpu, dtpm_cpu->cpu) = NULL;
+ }
+
kfree(dtpm_cpu);
}
@@ -178,11 +186,26 @@ static int cpuhp_dtpm_cpu_offline(unsigned int cpu)
static int cpuhp_dtpm_cpu_online(unsigned int cpu)
{
struct dtpm_cpu *dtpm_cpu;
+
+ dtpm_cpu = per_cpu(dtpm_per_cpu, cpu);
+ if (dtpm_cpu)
+ return dtpm_update_power(&dtpm_cpu->dtpm);
+
+ return 0;
+}
+
+static int __dtpm_cpu_setup(int cpu, struct dtpm *parent)
+{
+ struct dtpm_cpu *dtpm_cpu;
struct cpufreq_policy *policy;
struct em_perf_domain *pd;
char name[CPUFREQ_NAME_LEN];
int ret = -ENOMEM;
+ dtpm_cpu = per_cpu(dtpm_per_cpu, cpu);
+ if (dtpm_cpu)
+ return 0;
+
policy = cpufreq_cpu_get(cpu);
if (!policy)
return 0;
@@ -191,10 +214,6 @@ static int cpuhp_dtpm_cpu_online(unsigned int cpu)
if (!pd)
return -EINVAL;
- dtpm_cpu = per_cpu(dtpm_per_cpu, cpu);
- if (dtpm_cpu)
- return dtpm_update_power(&dtpm_cpu->dtpm);
-
dtpm_cpu = kzalloc(sizeof(*dtpm_cpu), GFP_KERNEL);
if (!dtpm_cpu)
return -ENOMEM;
@@ -207,7 +226,7 @@ static int cpuhp_dtpm_cpu_online(unsigned int cpu)
snprintf(name, sizeof(name), "cpu%d-cpufreq", dtpm_cpu->cpu);
- ret = dtpm_register(name, &dtpm_cpu->dtpm, NULL);
+ ret = dtpm_register(name, &dtpm_cpu->dtpm, parent);
if (ret)
goto out_kfree_dtpm_cpu;
@@ -231,7 +250,18 @@ out_kfree_dtpm_cpu:
return ret;
}
-static int __init dtpm_cpu_init(void)
+static int dtpm_cpu_setup(struct dtpm *dtpm, struct device_node *np)
+{
+ int cpu;
+
+ cpu = of_cpu_node_to_id(np);
+ if (cpu < 0)
+ return 0;
+
+ return __dtpm_cpu_setup(cpu, dtpm);
+}
+
+static int dtpm_cpu_init(void)
{
int ret;
@@ -269,4 +299,15 @@ static int __init dtpm_cpu_init(void)
return 0;
}
-DTPM_DECLARE(dtpm_cpu, dtpm_cpu_init);
+static void dtpm_cpu_exit(void)
+{
+ cpuhp_remove_state_nocalls(CPUHP_AP_ONLINE_DYN);
+ cpuhp_remove_state_nocalls(CPUHP_AP_DTPM_CPU_DEAD);
+}
+
+struct dtpm_subsys_ops dtpm_cpu_ops = {
+ .name = KBUILD_MODNAME,
+ .init = dtpm_cpu_init,
+ .exit = dtpm_cpu_exit,
+ .setup = dtpm_cpu_setup,
+};
diff --git a/drivers/powercap/dtpm_devfreq.c b/drivers/powercap/dtpm_devfreq.c
new file mode 100644
index 000000000000..91276761a31d
--- /dev/null
+++ b/drivers/powercap/dtpm_devfreq.c
@@ -0,0 +1,203 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2021 Linaro Limited
+ *
+ * Author: Daniel Lezcano <daniel.lezcano@linaro.org>
+ *
+ * The devfreq device combined with the energy model and the load can
+ * give an estimation of the power consumption as well as limiting the
+ * power.
+ *
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cpumask.h>
+#include <linux/devfreq.h>
+#include <linux/dtpm.h>
+#include <linux/energy_model.h>
+#include <linux/of.h>
+#include <linux/pm_qos.h>
+#include <linux/slab.h>
+#include <linux/units.h>
+
+struct dtpm_devfreq {
+ struct dtpm dtpm;
+ struct dev_pm_qos_request qos_req;
+ struct devfreq *devfreq;
+};
+
+static struct dtpm_devfreq *to_dtpm_devfreq(struct dtpm *dtpm)
+{
+ return container_of(dtpm, struct dtpm_devfreq, dtpm);
+}
+
+static int update_pd_power_uw(struct dtpm *dtpm)
+{
+ struct dtpm_devfreq *dtpm_devfreq = to_dtpm_devfreq(dtpm);
+ struct devfreq *devfreq = dtpm_devfreq->devfreq;
+ struct device *dev = devfreq->dev.parent;
+ struct em_perf_domain *pd = em_pd_get(dev);
+
+ dtpm->power_min = pd->table[0].power;
+ dtpm->power_min *= MICROWATT_PER_MILLIWATT;
+
+ dtpm->power_max = pd->table[pd->nr_perf_states - 1].power;
+ dtpm->power_max *= MICROWATT_PER_MILLIWATT;
+
+ return 0;
+}
+
+static u64 set_pd_power_limit(struct dtpm *dtpm, u64 power_limit)
+{
+ struct dtpm_devfreq *dtpm_devfreq = to_dtpm_devfreq(dtpm);
+ struct devfreq *devfreq = dtpm_devfreq->devfreq;
+ struct device *dev = devfreq->dev.parent;
+ struct em_perf_domain *pd = em_pd_get(dev);
+ unsigned long freq;
+ u64 power;
+ int i;
+
+ for (i = 0; i < pd->nr_perf_states; i++) {
+
+ power = pd->table[i].power * MICROWATT_PER_MILLIWATT;
+ if (power > power_limit)
+ break;
+ }
+
+ freq = pd->table[i - 1].frequency;
+
+ dev_pm_qos_update_request(&dtpm_devfreq->qos_req, freq);
+
+ power_limit = pd->table[i - 1].power * MICROWATT_PER_MILLIWATT;
+
+ return power_limit;
+}
+
+static void _normalize_load(struct devfreq_dev_status *status)
+{
+ if (status->total_time > 0xfffff) {
+ status->total_time >>= 10;
+ status->busy_time >>= 10;
+ }
+
+ status->busy_time <<= 10;
+ status->busy_time /= status->total_time ? : 1;
+
+ status->busy_time = status->busy_time ? : 1;
+ status->total_time = 1024;
+}
+
+static u64 get_pd_power_uw(struct dtpm *dtpm)
+{
+ struct dtpm_devfreq *dtpm_devfreq = to_dtpm_devfreq(dtpm);
+ struct devfreq *devfreq = dtpm_devfreq->devfreq;
+ struct device *dev = devfreq->dev.parent;
+ struct em_perf_domain *pd = em_pd_get(dev);
+ struct devfreq_dev_status status;
+ unsigned long freq;
+ u64 power;
+ int i;
+
+ mutex_lock(&devfreq->lock);
+ status = devfreq->last_status;
+ mutex_unlock(&devfreq->lock);
+
+ freq = DIV_ROUND_UP(status.current_frequency, HZ_PER_KHZ);
+ _normalize_load(&status);
+
+ for (i = 0; i < pd->nr_perf_states; i++) {
+
+ if (pd->table[i].frequency < freq)
+ continue;
+
+ power = pd->table[i].power * MICROWATT_PER_MILLIWATT;
+ power *= status.busy_time;
+ power >>= 10;
+
+ return power;
+ }
+
+ return 0;
+}
+
+static void pd_release(struct dtpm *dtpm)
+{
+ struct dtpm_devfreq *dtpm_devfreq = to_dtpm_devfreq(dtpm);
+
+ if (dev_pm_qos_request_active(&dtpm_devfreq->qos_req))
+ dev_pm_qos_remove_request(&dtpm_devfreq->qos_req);
+
+ kfree(dtpm_devfreq);
+}
+
+static struct dtpm_ops dtpm_ops = {
+ .set_power_uw = set_pd_power_limit,
+ .get_power_uw = get_pd_power_uw,
+ .update_power_uw = update_pd_power_uw,
+ .release = pd_release,
+};
+
+static int __dtpm_devfreq_setup(struct devfreq *devfreq, struct dtpm *parent)
+{
+ struct device *dev = devfreq->dev.parent;
+ struct dtpm_devfreq *dtpm_devfreq;
+ struct em_perf_domain *pd;
+ int ret = -ENOMEM;
+
+ pd = em_pd_get(dev);
+ if (!pd) {
+ ret = dev_pm_opp_of_register_em(dev, NULL);
+ if (ret) {
+ pr_err("No energy model available for '%s'\n", dev_name(dev));
+ return -EINVAL;
+ }
+ }
+
+ dtpm_devfreq = kzalloc(sizeof(*dtpm_devfreq), GFP_KERNEL);
+ if (!dtpm_devfreq)
+ return -ENOMEM;
+
+ dtpm_init(&dtpm_devfreq->dtpm, &dtpm_ops);
+
+ dtpm_devfreq->devfreq = devfreq;
+
+ ret = dtpm_register(dev_name(dev), &dtpm_devfreq->dtpm, parent);
+ if (ret) {
+ pr_err("Failed to register '%s': %d\n", dev_name(dev), ret);
+ kfree(dtpm_devfreq);
+ return ret;
+ }
+
+ ret = dev_pm_qos_add_request(dev, &dtpm_devfreq->qos_req,
+ DEV_PM_QOS_MAX_FREQUENCY,
+ PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE);
+ if (ret) {
+ pr_err("Failed to add QoS request: %d\n", ret);
+ goto out_dtpm_unregister;
+ }
+
+ dtpm_update_power(&dtpm_devfreq->dtpm);
+
+ return 0;
+
+out_dtpm_unregister:
+ dtpm_unregister(&dtpm_devfreq->dtpm);
+
+ return ret;
+}
+
+static int dtpm_devfreq_setup(struct dtpm *dtpm, struct device_node *np)
+{
+ struct devfreq *devfreq;
+
+ devfreq = devfreq_get_devfreq_by_node(np);
+ if (IS_ERR(devfreq))
+ return 0;
+
+ return __dtpm_devfreq_setup(devfreq, dtpm);
+}
+
+struct dtpm_subsys_ops dtpm_devfreq_ops = {
+ .name = KBUILD_MODNAME,
+ .setup = dtpm_devfreq_setup,
+};
diff --git a/drivers/powercap/dtpm_subsys.h b/drivers/powercap/dtpm_subsys.h
new file mode 100644
index 000000000000..db1712938a96
--- /dev/null
+++ b/drivers/powercap/dtpm_subsys.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2022 Linaro Ltd
+ *
+ * Author: Daniel Lezcano <daniel.lezcano@linaro.org>
+ */
+#ifndef ___DTPM_SUBSYS_H__
+#define ___DTPM_SUBSYS_H__
+
+extern struct dtpm_subsys_ops dtpm_cpu_ops;
+extern struct dtpm_subsys_ops dtpm_devfreq_ops;
+
+struct dtpm_subsys_ops *dtpm_subsys[] = {
+#ifdef CONFIG_DTPM_CPU
+ &dtpm_cpu_ops,
+#endif
+#ifdef CONFIG_DTPM_DEVFREQ
+ &dtpm_devfreq_ops,
+#endif
+};
+
+#endif