Merge branch 'pm-opp' (394f7164) · Commits · e / devices / android_kernel_sony_msm8998

arch/arm/mach-imx/mach-imx6q.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -350,7 +350,7 @@ static void __init imx6q_opp_init(void)
	return;		return;
	}		}

	if (of_init_opp_table(cpu_dev)) {		if (dev_pm_opp_of_add_table(cpu_dev)) {
	pr_warn("failed to init OPP table\n");		pr_warn("failed to init OPP table\n");
	goto put_node;		goto put_node;
	}		}

drivers/base/power/Makefile

+1 −1

Original line number	Original line	Diff line number	Diff line
	obj-$(CONFIG_PM) += sysfs.o generic_ops.o common.o qos.o runtime.o wakeirq.o		obj-$(CONFIG_PM) += sysfs.o generic_ops.o common.o qos.o runtime.o wakeirq.o
	obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o		obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o
	obj-$(CONFIG_PM_TRACE_RTC) += trace.o		obj-$(CONFIG_PM_TRACE_RTC) += trace.o
	obj-$(CONFIG_PM_OPP) += opp.o		obj-$(CONFIG_PM_OPP) += opp/
	obj-$(CONFIG_PM_GENERIC_DOMAINS) += domain.o domain_governor.o		obj-$(CONFIG_PM_GENERIC_DOMAINS) += domain.o domain_governor.o
	obj-$(CONFIG_HAVE_CLK) += clock_ops.o		obj-$(CONFIG_HAVE_CLK) += clock_ops.o

drivers/base/power/opp/Makefile

0 → 100644

+2 −0

Original line number	Original line	Diff line number	Diff line
			ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG
			obj-y += core.o cpu.o

drivers/base/power/opp.c→drivers/base/power/opp/core.c

+30 −333

Original line number	Original line	Diff line number	Diff line
	@@ -11,131 +11,14 @@
	* published by the Free Software Foundation.		* published by the Free Software Foundation.
	*/		*/

	#include <linux/cpu.h>
	#include <linux/kernel.h>
	#include <linux/errno.h>		#include <linux/errno.h>
	#include <linux/err.h>		#include <linux/err.h>
	#include <linux/slab.h>		#include <linux/slab.h>
	#include <linux/device.h>		#include <linux/device.h>
	#include <linux/list.h>
	#include <linux/rculist.h>
	#include <linux/rcupdate.h>
	#include <linux/pm_opp.h>
	#include <linux/of.h>		#include <linux/of.h>
	#include <linux/export.h>		#include <linux/export.h>

	/*		#include "opp.h"
	* Internal data structure organization with the OPP layer library is as
	* follows:
	* dev_opp_list (root)
	* \|- device 1 (represents voltage domain 1)
	* \| \|- opp 1 (availability, freq, voltage)
	* \| \|- opp 2 ..
	* ... ...
	* \| `- opp n ..
	* \|- device 2 (represents the next voltage domain)
	* ...
	* `- device m (represents mth voltage domain)
	* device 1, 2.. are represented by dev_opp structure while each opp
	* is represented by the opp structure.
	*/

	/**
	* struct dev_pm_opp - Generic OPP description structure
	* @node: opp list node. The nodes are maintained throughout the lifetime
	* of boot. It is expected only an optimal set of OPPs are
	* added to the library by the SoC framework.
	* RCU usage: opp list is traversed with RCU locks. node
	* modification is possible realtime, hence the modifications
	* are protected by the dev_opp_list_lock for integrity.
	* IMPORTANT: the opp nodes should be maintained in increasing
	* order.
	* @dynamic: not-created from static DT entries.
	* @available: true/false - marks if this OPP as available or not
	* @turbo: true if turbo (boost) OPP
	* @rate: Frequency in hertz
	* @u_volt: Target voltage in microvolts corresponding to this OPP
	* @u_volt_min: Minimum voltage in microvolts corresponding to this OPP
	* @u_volt_max: Maximum voltage in microvolts corresponding to this OPP
	* @u_amp: Maximum current drawn by the device in microamperes
	* @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
	* frequency from any other OPP's frequency.
	* @dev_opp: points back to the device_opp struct this opp belongs to
	* @rcu_head: RCU callback head used for deferred freeing
	* @np: OPP's device node.
	*
	* This structure stores the OPP information for a given device.
	*/
	struct dev_pm_opp {
	struct list_head node;

	bool available;
	bool dynamic;
	bool turbo;
	unsigned long rate;

	unsigned long u_volt;
	unsigned long u_volt_min;
	unsigned long u_volt_max;
	unsigned long u_amp;
	unsigned long clock_latency_ns;

	struct device_opp *dev_opp;
	struct rcu_head rcu_head;

	struct device_node *np;
	};

	/**
	* struct device_list_opp - devices managed by 'struct device_opp'
	* @node: list node
	* @dev: device to which the struct object belongs
	* @rcu_head: RCU callback head used for deferred freeing
	*
	* This is an internal data structure maintaining the list of devices that are
	* managed by 'struct device_opp'.
	*/
	struct device_list_opp {
	struct list_head node;
	const struct device *dev;
	struct rcu_head rcu_head;
	};

	/**
	* struct device_opp - Device opp structure
	* @node: list node - contains the devices with OPPs that
	* have been registered. Nodes once added are not modified in this
	* list.
	* RCU usage: nodes are not modified in the list of device_opp,
	* however addition is possible and is secured by dev_opp_list_lock
	* @srcu_head: notifier head to notify the OPP availability changes.
	* @rcu_head: RCU callback head used for deferred freeing
	* @dev_list: list of devices that share these OPPs
	* @opp_list: list of opps
	* @np: struct device_node pointer for opp's DT node.
	* @shared_opp: OPP is shared between multiple devices.
	*
	* This is an internal data structure maintaining the link to opps attached to
	* a device. This structure is not meant to be shared to users as it is
	* meant for book keeping and private to OPP library.
	*
	* Because the opp structures can be used from both rcu and srcu readers, we
	* need to wait for the grace period of both of them before freeing any
	* resources. And so we have used kfree_rcu() from within call_srcu() handlers.
	*/
	struct device_opp {
	struct list_head node;

	struct srcu_notifier_head srcu_head;
	struct rcu_head rcu_head;
	struct list_head dev_list;
	struct list_head opp_list;

	struct device_node *np;
	unsigned long clock_latency_ns_max;
	bool shared_opp;
	struct dev_pm_opp *suspend_opp;
	};

	/*		/*
	* The root of the list of all devices. All device_opp structures branch off		* The root of the list of all devices. All device_opp structures branch off
	@@ -200,7 +83,7 @@ static struct device_opp _managed_opp(const struct device_node np)
	* is a RCU protected pointer. This means that device_opp is valid as long		* is a RCU protected pointer. This means that device_opp is valid as long
	* as we are under RCU lock.		* as we are under RCU lock.
	*/		*/
	static struct device_opp _find_device_opp(struct device dev)		struct device_opp _find_device_opp(struct device dev)
	{		{
	struct device_opp *dev_opp;		struct device_opp *dev_opp;

	@@ -579,7 +462,7 @@ static void _remove_list_dev(struct device_list_opp *list_dev,
	_kfree_list_dev_rcu);		_kfree_list_dev_rcu);
	}		}

	static struct device_list_opp _add_list_dev(const struct device dev,		struct device_list_opp _add_list_dev(const struct device dev,
	struct device_opp *dev_opp)		struct device_opp *dev_opp)
	{		{
	struct device_list_opp *list_dev;		struct device_list_opp *list_dev;
	@@ -828,8 +711,8 @@ static int _opp_add(struct device dev, struct dev_pm_opp new_opp,
	* The opp is made available by default and it can be controlled using		* The opp is made available by default and it can be controlled using
	* dev_pm_opp_enable/disable functions and may be removed by dev_pm_opp_remove.		* dev_pm_opp_enable/disable functions and may be removed by dev_pm_opp_remove.
	*		*
	* NOTE: "dynamic" parameter impacts OPPs added by the of_init_opp_table and		* NOTE: "dynamic" parameter impacts OPPs added by the dev_pm_opp_of_add_table
	* freed by of_free_opp_table.		* and freed by dev_pm_opp_of_remove_table.
	*		*
	* Locking: The internal device_opp and opp structures are RCU protected.		* Locking: The internal device_opp and opp structures are RCU protected.
	* Hence this function internally uses RCU updater strategy with mutex locks		* Hence this function internally uses RCU updater strategy with mutex locks
	@@ -1220,7 +1103,8 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_notifier);

	#ifdef CONFIG_OF		#ifdef CONFIG_OF
	/**		/**
	* of_free_opp_table() - Free OPP table entries created from static DT entries		* dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
			* entries
	* @dev: device pointer used to lookup device OPPs.		* @dev: device pointer used to lookup device OPPs.
	*		*
	* Free OPPs created using static entries present in DT.		* Free OPPs created using static entries present in DT.
	@@ -1231,7 +1115,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_notifier);
	* that this function is NOT called under RCU protection or in contexts where		* that this function is NOT called under RCU protection or in contexts where
	* mutex cannot be locked.		* mutex cannot be locked.
	*/		*/
	void of_free_opp_table(struct device *dev)		void dev_pm_opp_of_remove_table(struct device *dev)
	{		{
	struct device_opp *dev_opp;		struct device_opp *dev_opp;
	struct dev_pm_opp opp, tmp;		struct dev_pm_opp opp, tmp;
	@@ -1266,91 +1150,34 @@ void of_free_opp_table(struct device *dev)
	unlock:		unlock:
	mutex_unlock(&dev_opp_list_lock);		mutex_unlock(&dev_opp_list_lock);
	}		}
	EXPORT_SYMBOL_GPL(of_free_opp_table);		EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);

	void of_cpumask_free_opp_table(cpumask_var_t cpumask)
	{
	struct device *cpu_dev;
	int cpu;

	WARN_ON(cpumask_empty(cpumask));

	for_each_cpu(cpu, cpumask) {
	cpu_dev = get_cpu_device(cpu);
	if (!cpu_dev) {
	pr_err("%s: failed to get cpu%d device\n", __func__,
	cpu);
	continue;
	}

	of_free_opp_table(cpu_dev);
	}
	}
	EXPORT_SYMBOL_GPL(of_cpumask_free_opp_table);

	/* Returns opp descriptor node from its phandle. Caller must do of_node_put() */		/* Returns opp descriptor node for a device, caller must do of_node_put() */
	static struct device_node *		struct device_node _of_get_opp_desc_node(struct device dev)
	_of_get_opp_desc_node_from_prop(struct device dev, const struct property prop)
	{		{
	struct device_node *opp_np;

	opp_np = of_find_node_by_phandle(be32_to_cpup(prop->value));
	if (!opp_np) {
	dev_err(dev, "%s: Prop: %s contains invalid opp desc phandle\n",
	__func__, prop->name);
	return ERR_PTR(-EINVAL);
	}

	return opp_np;
	}

	/* Returns opp descriptor node for a device. Caller must do of_node_put() */
	static struct device_node _of_get_opp_desc_node(struct device dev)
	{
	const struct property *prop;

	prop = of_find_property(dev->of_node, "operating-points-v2", NULL);
	if (!prop)
	return ERR_PTR(-ENODEV);
	if (!prop->value)
	return ERR_PTR(-ENODATA);

	/*		/*
	* TODO: Support for multiple OPP tables.		* TODO: Support for multiple OPP tables.
	*		*
	* There should be only ONE phandle present in "operating-points-v2"		* There should be only ONE phandle present in "operating-points-v2"
	* property.		* property.
	*/		*/
	if (prop->length != sizeof(__be32)) {
	dev_err(dev, "%s: Invalid opp desc phandle\n", __func__);
	return ERR_PTR(-EINVAL);
	}

	return _of_get_opp_desc_node_from_prop(dev, prop);		return of_parse_phandle(dev->of_node, "operating-points-v2", 0);
	}		}

	/* Initializes OPP tables based on new bindings */		/* Initializes OPP tables based on new bindings */
	static int _of_init_opp_table_v2(struct device *dev,		static int _of_add_opp_table_v2(struct device dev, struct device_node opp_np)
	const struct property *prop)
	{		{
	struct device_node opp_np, np;		struct device_node *np;
	struct device_opp *dev_opp;		struct device_opp *dev_opp;
	int ret = 0, count = 0;		int ret = 0, count = 0;

	if (!prop->value)
	return -ENODATA;

	/* Get opp node */
	opp_np = _of_get_opp_desc_node_from_prop(dev, prop);
	if (IS_ERR(opp_np))
	return PTR_ERR(opp_np);

	dev_opp = _managed_opp(opp_np);		dev_opp = _managed_opp(opp_np);
	if (dev_opp) {		if (dev_opp) {
	/* OPPs are already managed */		/* OPPs are already managed */
	if (!_add_list_dev(dev, dev_opp))		if (!_add_list_dev(dev, dev_opp))
	ret = -ENOMEM;		ret = -ENOMEM;
	goto put_opp_np;		return ret;
	}		}

	/* We have opp-list node now, iterate over it and add OPPs */		/* We have opp-list node now, iterate over it and add OPPs */
	@@ -1366,10 +1193,8 @@ static int _of_init_opp_table_v2(struct device *dev,
	}		}

	/* There should be one of more OPP defined */		/* There should be one of more OPP defined */
	if (WARN_ON(!count)) {		if (WARN_ON(!count))
	ret = -ENOENT;		return -ENOENT;
	goto put_opp_np;
	}

	dev_opp = _find_device_opp(dev);		dev_opp = _find_device_opp(dev);
	if (WARN_ON(IS_ERR(dev_opp))) {		if (WARN_ON(IS_ERR(dev_opp))) {
	@@ -1380,19 +1205,16 @@ static int _of_init_opp_table_v2(struct device *dev,
	dev_opp->np = opp_np;		dev_opp->np = opp_np;
	dev_opp->shared_opp = of_property_read_bool(opp_np, "opp-shared");		dev_opp->shared_opp = of_property_read_bool(opp_np, "opp-shared");

	of_node_put(opp_np);
	return 0;		return 0;

	free_table:		free_table:
	of_free_opp_table(dev);		dev_pm_opp_of_remove_table(dev);
	put_opp_np:
	of_node_put(opp_np);

	return ret;		return ret;
	}		}

	/* Initializes OPP tables based on old-deprecated bindings */		/* Initializes OPP tables based on old-deprecated bindings */
	static int _of_init_opp_table_v1(struct device *dev)		static int _of_add_opp_table_v1(struct device *dev)
	{		{
	const struct property *prop;		const struct property *prop;
	const __be32 *val;		const __be32 *val;
	@@ -1429,7 +1251,7 @@ static int _of_init_opp_table_v1(struct device *dev)
	}		}

	/**		/**
	* of_init_opp_table() - Initialize opp table from device tree		* dev_pm_opp_of_add_table() - Initialize opp table from device tree
	* @dev: device pointer used to lookup device OPPs.		* @dev: device pointer used to lookup device OPPs.
	*		*
	* Register the initial OPP table with the OPP library for given device.		* Register the initial OPP table with the OPP library for given device.
	@@ -1451,153 +1273,28 @@ static int _of_init_opp_table_v1(struct device *dev)
	* -ENODATA when empty 'operating-points' property is found		* -ENODATA when empty 'operating-points' property is found
	* -EINVAL when invalid entries are found in opp-v2 table		* -EINVAL when invalid entries are found in opp-v2 table
	*/		*/
	int of_init_opp_table(struct device *dev)		int dev_pm_opp_of_add_table(struct device *dev)
	{		{
	const struct property *prop;		struct device_node *opp_np;
			int ret;

	/*		/*
	* OPPs have two version of bindings now. The older one is deprecated,		* OPPs have two version of bindings now. The older one is deprecated,
	* try for the new binding first.		* try for the new binding first.
	*/		*/
	prop = of_find_property(dev->of_node, "operating-points-v2", NULL);		opp_np = _of_get_opp_desc_node(dev);
	if (!prop) {		if (!opp_np) {
	/*		/*
	* Try old-deprecated bindings for backward compatibility with		* Try old-deprecated bindings for backward compatibility with
	* older dtbs.		* older dtbs.
	*/		*/
	return _of_init_opp_table_v1(dev);		return _of_add_opp_table_v1(dev);
	}

	return _of_init_opp_table_v2(dev, prop);
	}
	EXPORT_SYMBOL_GPL(of_init_opp_table);

	int of_cpumask_init_opp_table(cpumask_var_t cpumask)
	{
	struct device *cpu_dev;
	int cpu, ret = 0;

	WARN_ON(cpumask_empty(cpumask));

	for_each_cpu(cpu, cpumask) {
	cpu_dev = get_cpu_device(cpu);
	if (!cpu_dev) {
	pr_err("%s: failed to get cpu%d device\n", __func__,
	cpu);
	continue;
	}

	ret = of_init_opp_table(cpu_dev);
	if (ret) {
	pr_err("%s: couldn't find opp table for cpu:%d, %d\n",
	__func__, cpu, ret);

	/* Free all other OPPs */
	of_cpumask_free_opp_table(cpumask);
	break;
	}
	}

	return ret;
	}
	EXPORT_SYMBOL_GPL(of_cpumask_init_opp_table);

	/* Required only for V1 bindings, as v2 can manage it from DT itself */
	int set_cpus_sharing_opps(struct device *cpu_dev, cpumask_var_t cpumask)
	{
	struct device_list_opp *list_dev;
	struct device_opp *dev_opp;
	struct device *dev;
	int cpu, ret = 0;

	rcu_read_lock();

	dev_opp = _find_device_opp(cpu_dev);
	if (IS_ERR(dev_opp)) {
	ret = -EINVAL;
	goto out_rcu_read_unlock;
	}

	for_each_cpu(cpu, cpumask) {
	if (cpu == cpu_dev->id)
	continue;

	dev = get_cpu_device(cpu);
	if (!dev) {
	dev_err(cpu_dev, "%s: failed to get cpu%d device\n",
	__func__, cpu);
	continue;
	}

	list_dev = _add_list_dev(dev, dev_opp);
	if (!list_dev) {
	dev_err(dev, "%s: failed to add list-dev for cpu%d device\n",
	__func__, cpu);
	continue;
	}
	}
	out_rcu_read_unlock:
	rcu_read_unlock();

	return 0;
	}
	EXPORT_SYMBOL_GPL(set_cpus_sharing_opps);

	/*
	* Works only for OPP v2 bindings.
	*
	* cpumask should be already set to mask of cpu_dev->id.
	* Returns -ENOENT if operating-points-v2 bindings aren't supported.
	*/
	int of_get_cpus_sharing_opps(struct device *cpu_dev, cpumask_var_t cpumask)
	{
	struct device_node np, tmp_np;
	struct device *tcpu_dev;
	int cpu, ret = 0;

	/* Get OPP descriptor node */
	np = _of_get_opp_desc_node(cpu_dev);
	if (IS_ERR(np)) {
	dev_dbg(cpu_dev, "%s: Couldn't find opp node: %ld\n", __func__,
	PTR_ERR(np));
	return -ENOENT;
	}		}

	/* OPPs are shared ? */		ret = _of_add_opp_table_v2(dev, opp_np);
	if (!of_property_read_bool(np, "opp-shared"))		of_node_put(opp_np);
	goto put_cpu_node;

	for_each_possible_cpu(cpu) {
	if (cpu == cpu_dev->id)
	continue;

	tcpu_dev = get_cpu_device(cpu);
	if (!tcpu_dev) {
	dev_err(cpu_dev, "%s: failed to get cpu%d device\n",
	__func__, cpu);
	ret = -ENODEV;
	goto put_cpu_node;
	}

	/* Get OPP descriptor node */
	tmp_np = _of_get_opp_desc_node(tcpu_dev);
	if (IS_ERR(tmp_np)) {
	dev_err(tcpu_dev, "%s: Couldn't find opp node: %ld\n",
	__func__, PTR_ERR(tmp_np));
	ret = PTR_ERR(tmp_np);
	goto put_cpu_node;
	}

	/* CPUs are sharing opp node */
	if (np == tmp_np)
	cpumask_set_cpu(cpu, cpumask);

	of_node_put(tmp_np);
	}

	put_cpu_node:
	of_node_put(np);
	return ret;		return ret;
	}		}
	EXPORT_SYMBOL_GPL(of_get_cpus_sharing_opps);		EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
	#endif		#endif

drivers/cpufreq/cpufreq_opp.c→drivers/base/power/opp/cpu.c

+267 −0

Original line number	Original line	Diff line number	Diff line
	/*		/*
	* Generic OPP helper interface for CPUFreq drivers		* Generic OPP helper interface for CPU device
	*		*
	* Copyright (C) 2009-2014 Texas Instruments Incorporated.		* Copyright (C) 2009-2014 Texas Instruments Incorporated.
	* Nishanth Menon		* Nishanth Menon
	@@ -10,16 +10,18 @@
	* it under the terms of the GNU General Public License version 2 as		* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.		* published by the Free Software Foundation.
	*/		*/
			#include <linux/cpu.h>
	#include <linux/cpufreq.h>		#include <linux/cpufreq.h>
	#include <linux/device.h>
	#include <linux/err.h>		#include <linux/err.h>
	#include <linux/errno.h>		#include <linux/errno.h>
	#include <linux/export.h>		#include <linux/export.h>
	#include <linux/kernel.h>		#include <linux/of.h>
	#include <linux/pm_opp.h>
	#include <linux/rcupdate.h>
	#include <linux/slab.h>		#include <linux/slab.h>

			#include "opp.h"

			#ifdef CONFIG_CPU_FREQ

	/**		/**
	* dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device		* dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device
	* @dev: device for which we do this operation		* @dev: device for which we do this operation
	@@ -112,3 +114,154 @@ void dev_pm_opp_free_cpufreq_table(struct device *dev,
	*table = NULL;		*table = NULL;
	}		}
	EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table);		EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table);
			#endif /* CONFIG_CPU_FREQ */

			/* Required only for V1 bindings, as v2 can manage it from DT itself */
			int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
			{
			struct device_list_opp *list_dev;
			struct device_opp *dev_opp;
			struct device *dev;
			int cpu, ret = 0;

			rcu_read_lock();

			dev_opp = _find_device_opp(cpu_dev);
			if (IS_ERR(dev_opp)) {
			ret = -EINVAL;
			goto out_rcu_read_unlock;
			}

			for_each_cpu(cpu, cpumask) {
			if (cpu == cpu_dev->id)
			continue;

			dev = get_cpu_device(cpu);
			if (!dev) {
			dev_err(cpu_dev, "%s: failed to get cpu%d device\n",
			__func__, cpu);
			continue;
			}

			list_dev = _add_list_dev(dev, dev_opp);
			if (!list_dev) {
			dev_err(dev, "%s: failed to add list-dev for cpu%d device\n",
			__func__, cpu);
			continue;
			}
			}
			out_rcu_read_unlock:
			rcu_read_unlock();

			return 0;
			}
			EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);

			#ifdef CONFIG_OF
			void dev_pm_opp_of_cpumask_remove_table(cpumask_var_t cpumask)
			{
			struct device *cpu_dev;
			int cpu;

			WARN_ON(cpumask_empty(cpumask));

			for_each_cpu(cpu, cpumask) {
			cpu_dev = get_cpu_device(cpu);
			if (!cpu_dev) {
			pr_err("%s: failed to get cpu%d device\n", __func__,
			cpu);
			continue;
			}

			dev_pm_opp_of_remove_table(cpu_dev);
			}
			}
			EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);

			int dev_pm_opp_of_cpumask_add_table(cpumask_var_t cpumask)
			{
			struct device *cpu_dev;
			int cpu, ret = 0;

			WARN_ON(cpumask_empty(cpumask));

			for_each_cpu(cpu, cpumask) {
			cpu_dev = get_cpu_device(cpu);
			if (!cpu_dev) {
			pr_err("%s: failed to get cpu%d device\n", __func__,
			cpu);
			continue;
			}

			ret = dev_pm_opp_of_add_table(cpu_dev);
			if (ret) {
			pr_err("%s: couldn't find opp table for cpu:%d, %d\n",
			__func__, cpu, ret);

			/* Free all other OPPs */
			dev_pm_opp_of_cpumask_remove_table(cpumask);
			break;
			}
			}

			return ret;
			}
			EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);

			/*
			* Works only for OPP v2 bindings.
			*
			* cpumask should be already set to mask of cpu_dev->id.
			* Returns -ENOENT if operating-points-v2 bindings aren't supported.
			*/
			int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
			{
			struct device_node np, tmp_np;
			struct device *tcpu_dev;
			int cpu, ret = 0;

			/* Get OPP descriptor node */
			np = _of_get_opp_desc_node(cpu_dev);
			if (!np) {
			dev_dbg(cpu_dev, "%s: Couldn't find cpu_dev node.\n", __func__);
			return -ENOENT;
			}

			/* OPPs are shared ? */
			if (!of_property_read_bool(np, "opp-shared"))
			goto put_cpu_node;

			for_each_possible_cpu(cpu) {
			if (cpu == cpu_dev->id)
			continue;

			tcpu_dev = get_cpu_device(cpu);
			if (!tcpu_dev) {
			dev_err(cpu_dev, "%s: failed to get cpu%d device\n",
			__func__, cpu);
			ret = -ENODEV;
			goto put_cpu_node;
			}

			/* Get OPP descriptor node */
			tmp_np = _of_get_opp_desc_node(tcpu_dev);
			if (!tmp_np) {
			dev_err(tcpu_dev, "%s: Couldn't find tcpu_dev node.\n",
			__func__);
			ret = -ENOENT;
			goto put_cpu_node;
			}

			/* CPUs are sharing opp node */
			if (np == tmp_np)
			cpumask_set_cpu(cpu, cpumask);

			of_node_put(tmp_np);
			}

			put_cpu_node:
			of_node_put(np);
			return ret;
			}
			EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
			#endif