Commit f59d3ee8 authored by Viresh Kumar's avatar Viresh Kumar Committed by Rafael J. Wysocki
Browse files

PM / OPP: Move cpu specific code to opp/cpu.c 



Move cpu device specific code out of generic opp library, and add it to
cpu.c.

Along with that, create a core-internal opp.h header, which will be used
to share structures and function prototypes within opp core.

Reviewed-by: default avatarStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 33692dc3

drivers/base/power/opp/core.c

+5 −271
Original line number Diff line number Diff line
@@ -11,131 +11,14 @@ 
 * published by the Free Software Foundation.

 */



#include <linux/cpu.h>

#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/err.h>

#include <linux/slab.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/export.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;

};

#include "opp.h"



/*

 * 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

 * 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;
@@ -579,7 +462,7 @@ static void _remove_list_dev(struct device_list_opp *list_dev, 
		  _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_list_opp *list_dev;
@@ -1262,28 +1145,8 @@ unlock: 
}

EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);



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);



/* 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)

struct device_node *_of_get_opp_desc_node(struct device *dev)

{

	/*

	 * TODO: Support for multiple OPP tables.
@@ -1427,133 +1290,4 @@ int dev_pm_opp_of_add_table(struct device *dev) 
	return ret;

}

EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_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);



/* 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);



/*

 * 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 opp node: %ld\n", __func__,

			PTR_ERR(np));

		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 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;

}

EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);

#endif

drivers/base/power/opp/cpu.c

+156 −4
Original line number Diff line number Diff line
@@ -10,17 +10,18 @@ 
 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

#include <linux/cpu.h>

#include <linux/cpufreq.h>

#include <linux/device.h>

#include <linux/err.h>

#include <linux/errno.h>

#include <linux/export.h>

#include <linux/kernel.h>

#include <linux/pm_opp.h>

#include <linux/rcupdate.h>

#include <linux/of.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:	device for which we do this operation
@@ -114,3 +115,154 @@ void dev_pm_opp_free_cpufreq_table(struct device *dev, 
}

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 opp node: %ld\n", __func__,

			PTR_ERR(np));

		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 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;

}

EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);

#endif

drivers/base/power/opp/opp.h

0 → 100644
+143 −0
Original line number Diff line number Diff line 
/*

 * Generic OPP Interface

 *

 * Copyright (C) 2009-2010 Texas Instruments Incorporated.

 *	Nishanth Menon

 *	Romit Dasgupta

 *	Kevin Hilman

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */



#ifndef __DRIVER_OPP_H__

#define __DRIVER_OPP_H__



#include <linux/device.h>

#include <linux/kernel.h>

#include <linux/list.h>

#include <linux/pm_opp.h>

#include <linux/rculist.h>

#include <linux/rcupdate.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;

};



/* Routines internal to opp core */

struct device_opp *_find_device_opp(struct device *dev);

struct device_list_opp *_add_list_dev(const struct device *dev,

				      struct device_opp *dev_opp);

struct device_node *_of_get_opp_desc_node(struct device *dev);



#endif		/* __DRIVER_OPP_H__ */

CRA Git | Maintained and supported by SUSTech CRA and CCSE