| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20250115-feature_regulator_pw_budget-v2-1-0a44b949e6bc@bootlin.com>
Date: Wed, 15 Jan 2025 15:41:57 +0100
From: Kory Maincent <kory.maincent@...tlin.com>
To: Liam Girdwood <lgirdwood@...il.com>, Mark Brown <broonie@...nel.org>,
Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>,
Conor Dooley <conor+dt@...nel.org>
Cc: Thomas Petazzoni <thomas.petazzoni@...tlin.com>,
linux-kernel@...r.kernel.org, devicetree@...r.kernel.org,
Oleksij Rempel <o.rempel@...gutronix.de>, kernel@...gutronix.de,
Kory Maincent <kory.maincent@...tlin.com>
Subject: [PATCH v2 1/2] regulator: Add support for power budget
Introduce power budget management for the regulator device. Enable tracking
of available power capacity by providing helpers to request and release
power budget allocations.
Signed-off-by: Kory Maincent <kory.maincent@...tlin.com>
---
Change in v2:
- Add event notifier in case of power request over budget.
- Track how much budget is used instead of free power budget.
---
drivers/regulator/core.c | 114 +++++++++++++++++++++++++++++++++++++
drivers/regulator/of_regulator.c | 3 +
include/linux/regulator/consumer.h | 21 +++++++
include/linux/regulator/driver.h | 2 +
include/linux/regulator/machine.h | 2 +
5 files changed, 142 insertions(+)
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index c092b78c5f12..6c0ef1182248 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -917,6 +917,26 @@ static ssize_t bypass_show(struct device *dev,
}
static DEVICE_ATTR_RO(bypass);
+static ssize_t power_budget_milliwatt_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", rdev->constraints->pw_budget_mW);
+}
+static DEVICE_ATTR_RO(power_budget_milliwatt);
+
+static ssize_t power_requested_milliwatt_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct regulator_dev *rdev = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", rdev->pw_requested_mW);
+}
+static DEVICE_ATTR_RO(power_requested_milliwatt);
+
#define REGULATOR_ERROR_ATTR(name, bit) \
static ssize_t name##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
@@ -1149,6 +1169,10 @@ static void print_constraints_debug(struct regulator_dev *rdev)
if (constraints->valid_modes_mask & REGULATOR_MODE_STANDBY)
count += scnprintf(buf + count, len - count, "standby ");
+ if (constraints->pw_budget_mW)
+ count += scnprintf(buf + count, len - count, "%d mW budget",
+ constraints->pw_budget_mW);
+
if (!count)
count = scnprintf(buf, len, "no parameters");
else
@@ -1627,6 +1651,9 @@ static int set_machine_constraints(struct regulator_dev *rdev)
rdev->last_off = ktime_get();
}
+ if (!rdev->constraints->pw_budget_mW)
+ rdev->constraints->pw_budget_mW = INT_MAX;
+
print_constraints(rdev);
return 0;
}
@@ -4601,6 +4628,87 @@ int regulator_get_current_limit(struct regulator *regulator)
}
EXPORT_SYMBOL_GPL(regulator_get_current_limit);
+/**
+ * regulator_get_unclaimed_power_budget - get regulator unclaimed power budget
+ * @regulator: regulator source
+ *
+ * Return: Unclaimed power budget of the regulator in mW.
+ */
+int regulator_get_unclaimed_power_budget(struct regulator *regulator)
+{
+ return regulator->rdev->constraints->pw_budget_mW -
+ regulator->rdev->pw_requested_mW;
+}
+EXPORT_SYMBOL_GPL(regulator_get_unclaimed_power_budget);
+
+/**
+ * regulator_request_power_budget - request power budget on a regulator
+ * @regulator: regulator source
+ * @pw_req: Power requested
+ *
+ * Return: 0 on success or a negative error number on failure.
+ */
+int regulator_request_power_budget(struct regulator *regulator,
+ unsigned int pw_req)
+{
+ struct regulator_dev *rdev = regulator->rdev;
+ int ret = 0, pw_tot_req;
+
+ regulator_lock(rdev);
+ if (rdev->supply) {
+ ret = regulator_request_power_budget(rdev->supply, pw_req);
+ if (ret < 0)
+ goto out;
+ }
+
+ pw_tot_req = rdev->pw_requested_mW + pw_req;
+ if (pw_tot_req > rdev->constraints->pw_budget_mW) {
+ rdev_warn(rdev, "power requested %d mW out of budget %d mW",
+ pw_req,
+ rdev->constraints->pw_budget_mW - rdev->pw_requested_mW);
+ regulator_notifier_call_chain(rdev,
+ REGULATOR_EVENT_OVER_CURRENT_WARN,
+ NULL);
+ ret = -ERANGE;
+ goto out;
+ }
+
+ rdev->pw_requested_mW = pw_tot_req;
+out:
+ regulator_unlock(rdev);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(regulator_request_power_budget);
+
+/**
+ * regulator_free_power_budget - free power budget on a regulator
+ * @regulator: regulator source
+ * @pw: Power to be released.
+ *
+ * Return: Power budget of the regulator in mW.
+ */
+void regulator_free_power_budget(struct regulator *regulator,
+ unsigned int pw)
+{
+ struct regulator_dev *rdev = regulator->rdev;
+ int pw_tot_req;
+
+ regulator_lock(rdev);
+ if (rdev->supply)
+ regulator_free_power_budget(rdev->supply, pw);
+
+ pw_tot_req = rdev->pw_requested_mW - pw;
+ if (pw_tot_req >= 0)
+ rdev->pw_requested_mW = pw_tot_req;
+ else
+ rdev_warn(rdev,
+ "too much power freed %d mW (already requested %d mW)",
+ pw, rdev->pw_requested_mW);
+
+ regulator_unlock(rdev);
+}
+EXPORT_SYMBOL_GPL(regulator_free_power_budget);
+
/**
* regulator_set_mode - set regulator operating mode
* @regulator: regulator source
@@ -5239,6 +5347,8 @@ static struct attribute *regulator_dev_attrs[] = {
&dev_attr_suspend_standby_mode.attr,
&dev_attr_suspend_mem_mode.attr,
&dev_attr_suspend_disk_mode.attr,
+ &dev_attr_power_budget_milliwatt.attr,
+ &dev_attr_power_requested_milliwatt.attr,
NULL
};
@@ -5320,6 +5430,10 @@ static umode_t regulator_attr_is_visible(struct kobject *kobj,
attr == &dev_attr_suspend_disk_mode.attr)
return ops->set_suspend_mode ? mode : 0;
+ if (attr == &dev_attr_power_budget_milliwatt.attr ||
+ attr == &dev_attr_power_requested_milliwatt.attr)
+ return rdev->constraints->pw_budget_mW != INT_MAX ? mode : 0;
+
return mode;
}
diff --git a/drivers/regulator/of_regulator.c b/drivers/regulator/of_regulator.c
index 6af8411679c7..011088c57891 100644
--- a/drivers/regulator/of_regulator.c
+++ b/drivers/regulator/of_regulator.c
@@ -125,6 +125,9 @@ static int of_get_regulation_constraints(struct device *dev,
if (constraints->min_uA != constraints->max_uA)
constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
+ if (!of_property_read_u32(np, "regulator-power-budget-milliwatt", &pval))
+ constraints->pw_budget_mW = pval;
+
constraints->boot_on = of_property_read_bool(np, "regulator-boot-on");
constraints->always_on = of_property_read_bool(np, "regulator-always-on");
if (!constraints->always_on) /* status change should be possible. */
diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h
index bcba3935c6f9..ffe912f345ae 100644
--- a/include/linux/regulator/consumer.h
+++ b/include/linux/regulator/consumer.h
@@ -233,6 +233,11 @@ int regulator_sync_voltage(struct regulator *regulator);
int regulator_set_current_limit(struct regulator *regulator,
int min_uA, int max_uA);
int regulator_get_current_limit(struct regulator *regulator);
+int regulator_get_unclaimed_power_budget(struct regulator *regulator);
+int regulator_request_power_budget(struct regulator *regulator,
+ unsigned int pw_req);
+void regulator_free_power_budget(struct regulator *regulator,
+ unsigned int pw);
int regulator_set_mode(struct regulator *regulator, unsigned int mode);
unsigned int regulator_get_mode(struct regulator *regulator);
@@ -526,6 +531,22 @@ static inline int regulator_get_current_limit(struct regulator *regulator)
return 0;
}
+static inline int regulator_get_unclaimed_power_budget(struct regulator *regulator)
+{
+ return INT_MAX;
+}
+
+static inline int regulator_request_power_budget(struct regulator *regulator,
+ unsigned int pw_req)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline void regulator_free_power_budget(struct regulator *regulator,
+ unsigned int pw)
+{
+}
+
static inline int regulator_set_mode(struct regulator *regulator,
unsigned int mode)
{
diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h
index 5b66caf1695d..4a216fdba354 100644
--- a/include/linux/regulator/driver.h
+++ b/include/linux/regulator/driver.h
@@ -656,6 +656,8 @@ struct regulator_dev {
int cached_err;
bool use_cached_err;
spinlock_t err_lock;
+
+ int pw_requested_mW;
};
/*
diff --git a/include/linux/regulator/machine.h b/include/linux/regulator/machine.h
index b3db09a7429b..1fc440c5c4c7 100644
--- a/include/linux/regulator/machine.h
+++ b/include/linux/regulator/machine.h
@@ -113,6 +113,7 @@ struct notification_limit {
* @min_uA: Smallest current consumers may set.
* @max_uA: Largest current consumers may set.
* @ilim_uA: Maximum input current.
+ * @pw_budget_mW: Power budget for the regulator in mW.
* @system_load: Load that isn't captured by any consumer requests.
*
* @over_curr_limits: Limits for acting on over current.
@@ -185,6 +186,7 @@ struct regulation_constraints {
int max_uA;
int ilim_uA;
+ int pw_budget_mW;
int system_load;
/* used for coupled regulators */
--
2.34.1
Powered by blists - more mailing lists