Commit 6f707daa authored by Viresh Kumar's avatar Viresh Kumar Committed by Rafael J. Wysocki
Browse files

PM / OPP: Add dev_pm_opp_get_sharing_cpus() 



OPP core allows a platform to mark OPP table as shared, when the
platform isn't using operating-points-v2 bindings.

And, so there should be a non DT way of finding out if the OPP table is
shared or not.

This patch adds dev_pm_opp_get_sharing_cpus(), which first tries to get
OPP sharing information from the opp-table (in case it is already marked
as shared), otherwise it uses the existing DT way of finding sharing
information.

Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent dde370b2

drivers/base/power/opp/cpu.c

+45 −0
Original line number Diff line number Diff line
@@ -330,3 +330,48 @@ unlock: 
	return ret;

}

EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);



/**

 * dev_pm_opp_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with @cpu_dev

 * @cpu_dev:	CPU device for which we do this operation

 * @cpumask:	cpumask to update with information of sharing CPUs

 *

 * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.

 *

 * Returns -ENODEV if OPP table isn't already present.

 *

 * Locking: The internal opp_table and opp structures are RCU protected.

 * Hence this function internally uses RCU updater strategy with mutex locks

 * to keep the integrity of the internal data structures. Callers should ensure

 * that this function is *NOT* called under RCU protection or in contexts where

 * mutex cannot be locked.

 */

int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)

{

	struct opp_device *opp_dev;

	struct opp_table *opp_table;

	int ret = 0;



	mutex_lock(&opp_table_lock);



	opp_table = _find_opp_table(cpu_dev);

	if (IS_ERR(opp_table)) {

		ret = PTR_ERR(opp_table);

		goto unlock;

	}



	cpumask_clear(cpumask);



	if (opp_table->shared_opp) {

		list_for_each_entry(opp_dev, &opp_table->dev_list, node)

			cpumask_set_cpu(opp_dev->dev->id, cpumask);

	} else {

		cpumask_set_cpu(cpu_dev->id, cpumask);

	}



unlock:

	mutex_unlock(&opp_table_lock);



	return ret;

}

EXPORT_SYMBOL_GPL(dev_pm_opp_get_sharing_cpus);

include/linux/pm_opp.h

+6 −0
Original line number Diff line number Diff line
@@ -66,6 +66,7 @@ int dev_pm_opp_set_regulator(struct device *dev, const char *name); 
void dev_pm_opp_put_regulator(struct device *dev);

int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq);

int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, const cpumask_var_t cpumask);

int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask);

#else

static inline unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)

{
@@ -184,6 +185,11 @@ static inline int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, const cpum 
	return -ENOTSUPP;

}



static inline int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)

{

	return -EINVAL;

}



#endif		/* CONFIG_PM_OPP */



#if defined(CONFIG_PM_OPP) && defined(CONFIG_OF)

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