[linux-2.6-block.git] / drivers / opp / cpu.c

/*
 * Generic OPP helper interface for CPU device
 *
 * Copyright (C) 2009-2014 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.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/cpu.h>
#include <linux/cpufreq.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/export.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
 * @table:	Cpufreq table returned back to caller
 *
 * Generate a cpufreq table for a provided device- this assumes that the
 * opp table is already initialized and ready for usage.
 *
 * This function allocates required memory for the cpufreq table. It is
 * expected that the caller does the required maintenance such as freeing
 * the table as required.
 *
 * Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM
 * if no memory available for the operation (table is not populated), returns 0
 * if successful and table is populated.
 *
 * WARNING: It is  important for the callers to ensure refreshing their copy of
 * the table if any of the mentioned functions have been invoked in the interim.
 */
int dev_pm_opp_init_cpufreq_table(struct device *dev,
				  struct cpufreq_frequency_table **table)
{
	struct dev_pm_opp *opp;
	struct cpufreq_frequency_table *freq_table = NULL;
	int i, max_opps, ret = 0;
	unsigned long rate;

	max_opps = dev_pm_opp_get_opp_count(dev);
	if (max_opps <= 0)
		return max_opps ? max_opps : -ENODATA;

	freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_KERNEL);
	if (!freq_table)
		return -ENOMEM;

	for (i = 0, rate = 0; i < max_opps; i++, rate++) {
		/* find next rate */
		opp = dev_pm_opp_find_freq_ceil(dev, &rate);
		if (IS_ERR(opp)) {
			ret = PTR_ERR(opp);
			goto out;
		}
		freq_table[i].driver_data = i;
		freq_table[i].frequency = rate / 1000;

		/* Is Boost/turbo opp ? */
		if (dev_pm_opp_is_turbo(opp))
			freq_table[i].flags = CPUFREQ_BOOST_FREQ;

		dev_pm_opp_put(opp);
	}

	freq_table[i].driver_data = i;
	freq_table[i].frequency = CPUFREQ_TABLE_END;

	*table = &freq_table[0];

out:
	if (ret)
		kfree(freq_table);

	return ret;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_init_cpufreq_table);

/**
 * dev_pm_opp_free_cpufreq_table() - free the cpufreq table
 * @dev:	device for which we do this operation
 * @table:	table to free
 *
 * Free up the table allocated by dev_pm_opp_init_cpufreq_table
 */
void dev_pm_opp_free_cpufreq_table(struct device *dev,
				   struct cpufreq_frequency_table **table)
{
	if (!table)
		return;

	kfree(*table);
	*table = NULL;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table);
#endif	/* CONFIG_CPU_FREQ */

void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask,
				      int last_cpu)
{
	struct device *cpu_dev;
	int cpu;

	WARN_ON(cpumask_empty(cpumask));

	for_each_cpu(cpu, cpumask) {
		if (cpu == last_cpu)
			break;

		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_find_and_remove_table(cpu_dev);
	}
}

/**
 * dev_pm_opp_cpumask_remove_table() - Removes OPP table for @cpumask
 * @cpumask:	cpumask for which OPP table needs to be removed
 *
 * This removes the OPP tables for CPUs present in the @cpumask.
 * This should be used to remove all the OPPs entries associated with
 * the cpus in @cpumask.
 */
void dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask)
{
	_dev_pm_opp_cpumask_remove_table(cpumask, -1);
}
EXPORT_SYMBOL_GPL(dev_pm_opp_cpumask_remove_table);

/**
 * dev_pm_opp_set_sharing_cpus() - Mark OPP table as shared by few CPUs
 * @cpu_dev:	CPU device for which we do this operation
 * @cpumask:	cpumask of the CPUs which share the OPP table with @cpu_dev
 *
 * This marks OPP table of the @cpu_dev as shared by the CPUs present in
 * @cpumask.
 *
 * Returns -ENODEV if OPP table isn't already present.
 */
int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev,
				const struct cpumask *cpumask)
{
	struct opp_device *opp_dev;
	struct opp_table *opp_table;
	struct device *dev;
	int cpu, ret = 0;

	opp_table = _find_opp_table(cpu_dev);
	if (IS_ERR(opp_table))
		return PTR_ERR(opp_table);

	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;
		}

		opp_dev = _add_opp_dev(dev, opp_table);
		if (!opp_dev) {
			dev_err(dev, "%s: failed to add opp-dev for cpu%d device\n",
				__func__, cpu);
			continue;
		}

		/* Mark opp-table as multiple CPUs are sharing it now */
		opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
	}

	dev_pm_opp_put_opp_table(opp_table);

	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 and -EINVAL if the OPP
 * table's status is access-unknown.
 */
int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)
{
	struct opp_device *opp_dev;
	struct opp_table *opp_table;
	int ret = 0;

	opp_table = _find_opp_table(cpu_dev);
	if (IS_ERR(opp_table))
		return PTR_ERR(opp_table);

	if (opp_table->shared_opp == OPP_TABLE_ACCESS_UNKNOWN) {
		ret = -EINVAL;
		goto put_opp_table;
	}

	cpumask_clear(cpumask);

	if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
		mutex_lock(&opp_table->lock);
		list_for_each_entry(opp_dev, &opp_table->dev_list, node)
			cpumask_set_cpu(opp_dev->dev->id, cpumask);
		mutex_unlock(&opp_table->lock);
	} else {
		cpumask_set_cpu(cpu_dev->id, cpumask);
	}

put_opp_table:
	dev_pm_opp_put_opp_table(opp_table);

	return ret;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_get_sharing_cpus);
Commit	Line	Data
a0dd7b79	1	/*
33692dc3	2	* Generic OPP helper interface for CPU device
a0dd7b79 NM	3	*
	4	* Copyright (C) 2009-2014 Texas Instruments Incorporated.
	5	* Nishanth Menon
	6	* Romit Dasgupta
	7	* Kevin Hilman
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*/
d6d2a528 VK	13
	14	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	15
f59d3ee8	16	#include <linux/cpu.h>
a0dd7b79	17	#include <linux/cpufreq.h>
a0dd7b79 NM	18	#include <linux/err.h>
	19	#include <linux/errno.h>
	20	#include <linux/export.h>
a0dd7b79 NM	21	#include <linux/slab.h>
a0dd7b79 NM	22
f59d3ee8 VK	23	#include "opp.h"
f59d3ee8 VK	24
33692dc3	25	#ifdef CONFIG_CPU_FREQ
f59d3ee8	26
a0dd7b79 NM	27	/**
	28	* dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device
	29	* @dev: device for which we do this operation
	30	* @table: Cpufreq table returned back to caller
	31	*
	32	* Generate a cpufreq table for a provided device- this assumes that the
2c2709dc	33	* opp table is already initialized and ready for usage.
a0dd7b79 NM	34	*
	35	* This function allocates required memory for the cpufreq table. It is
	36	* expected that the caller does the required maintenance such as freeing
	37	* the table as required.
	38	*
	39	* Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM
	40	* if no memory available for the operation (table is not populated), returns 0
	41	* if successful and table is populated.
	42	*
	43	* WARNING: It is important for the callers to ensure refreshing their copy of
	44	* the table if any of the mentioned functions have been invoked in the interim.
a0dd7b79 NM	45	*/
	46	int dev_pm_opp_init_cpufreq_table(struct device *dev,
	47	struct cpufreq_frequency_table **table)
	48	{
	49	struct dev_pm_opp *opp;
	50	struct cpufreq_frequency_table *freq_table = NULL;
	51	int i, max_opps, ret = 0;
	52	unsigned long rate;
	53
a0dd7b79	54	max_opps = dev_pm_opp_get_opp_count(dev);
8a31d9d9 VK	55	if (max_opps <= 0)
8a31d9d9 VK	56	return max_opps ? max_opps : -ENODATA;
a0dd7b79	57
4a823c0b	58	freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_KERNEL);
8a31d9d9 VK	59	if (!freq_table)
8a31d9d9 VK	60	return -ENOMEM;
a0dd7b79 NM	61
	62	for (i = 0, rate = 0; i < max_opps; i++, rate++) {
	63	/* find next rate */
	64	opp = dev_pm_opp_find_freq_ceil(dev, &rate);
	65	if (IS_ERR(opp)) {
	66	ret = PTR_ERR(opp);
	67	goto out;
	68	}
	69	freq_table[i].driver_data = i;
	70	freq_table[i].frequency = rate / 1000;
79eea44a BZ	71
	72	/* Is Boost/turbo opp ? */
	73	if (dev_pm_opp_is_turbo(opp))
	74	freq_table[i].flags = CPUFREQ_BOOST_FREQ;
8a31d9d9 VK	75
8a31d9d9 VK	76	dev_pm_opp_put(opp);
a0dd7b79 NM	77	}
	78
	79	freq_table[i].driver_data = i;
	80	freq_table[i].frequency = CPUFREQ_TABLE_END;
	81
	82	*table = &freq_table[0];
	83
	84	out:
a0dd7b79 NM	85	if (ret)
	86	kfree(freq_table);
	87
	88	return ret;
	89	}
	90	EXPORT_SYMBOL_GPL(dev_pm_opp_init_cpufreq_table);
	91
	92	/**
	93	* dev_pm_opp_free_cpufreq_table() - free the cpufreq table
	94	* @dev: device for which we do this operation
	95	* @table: table to free
	96	*
	97	* Free up the table allocated by dev_pm_opp_init_cpufreq_table
	98	*/
	99	void dev_pm_opp_free_cpufreq_table(struct device *dev,
	100	struct cpufreq_frequency_table **table)
	101	{
	102	if (!table)
	103	return;
	104
	105	kfree(*table);
	106	*table = NULL;
	107	}
	108	EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table);
33692dc3	109	#endif /* CONFIG_CPU_FREQ */
f59d3ee8	110
2a4eb735	111	void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask,
404b1369	112	int last_cpu)
f59d3ee8 VK	113	{
	114	struct device *cpu_dev;
	115	int cpu;
	116
	117	WARN_ON(cpumask_empty(cpumask));
	118
	119	for_each_cpu(cpu, cpumask) {
404b1369 VK	120	if (cpu == last_cpu)
	121	break;
	122
f59d3ee8 VK	123	cpu_dev = get_cpu_device(cpu);
	124	if (!cpu_dev) {
	125	pr_err("%s: failed to get cpu%d device\n", __func__,
	126	cpu);
	127	continue;
	128	}
	129
2a4eb735	130	_dev_pm_opp_find_and_remove_table(cpu_dev);
f59d3ee8 VK	131	}
f59d3ee8 VK	132	}
411466c5 SH	133
	134	/**
	135	* dev_pm_opp_cpumask_remove_table() - Removes OPP table for @cpumask
	136	* @cpumask: cpumask for which OPP table needs to be removed
	137	*
	138	* This removes the OPP tables for CPUs present in the @cpumask.
	139	* This should be used to remove all the OPPs entries associated with
	140	* the cpus in @cpumask.
411466c5 SH	141	*/
	142	void dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask)
	143	{
2a4eb735	144	_dev_pm_opp_cpumask_remove_table(cpumask, -1);
411466c5 SH	145	}
	146	EXPORT_SYMBOL_GPL(dev_pm_opp_cpumask_remove_table);
	147
2c93104f VK	148	/**
	149	* dev_pm_opp_set_sharing_cpus() - Mark OPP table as shared by few CPUs
	150	* @cpu_dev: CPU device for which we do this operation
	151	* @cpumask: cpumask of the CPUs which share the OPP table with @cpu_dev
	152	*
	153	* This marks OPP table of the @cpu_dev as shared by the CPUs present in
	154	* @cpumask.
	155	*
	156	* Returns -ENODEV if OPP table isn't already present.
2c93104f	157	*/
dde370b2	158	int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev,
ddbb74bc	159	const struct cpumask *cpumask)
2c93104f VK	160	{
	161	struct opp_device *opp_dev;
	162	struct opp_table *opp_table;
	163	struct device *dev;
	164	int cpu, ret = 0;
	165
2c93104f	166	opp_table = _find_opp_table(cpu_dev);
5b650b38 VK	167	if (IS_ERR(opp_table))
5b650b38 VK	168	return PTR_ERR(opp_table);
2c93104f VK	169
	170	for_each_cpu(cpu, cpumask) {
	171	if (cpu == cpu_dev->id)
	172	continue;
	173
	174	dev = get_cpu_device(cpu);
	175	if (!dev) {
	176	dev_err(cpu_dev, "%s: failed to get cpu%d device\n",
	177	__func__, cpu);
	178	continue;
	179	}
	180
	181	opp_dev = _add_opp_dev(dev, opp_table);
	182	if (!opp_dev) {
	183	dev_err(dev, "%s: failed to add opp-dev for cpu%d device\n",
	184	__func__, cpu);
	185	continue;
	186	}
46e7a4e1 VK	187
46e7a4e1 VK	188	/* Mark opp-table as multiple CPUs are sharing it now */
79ee2e8f	189	opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
2c93104f	190	}
5b650b38 VK	191
5b650b38 VK	192	dev_pm_opp_put_opp_table(opp_table);
2c93104f VK	193
	194	return ret;
	195	}
	196	EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);
6f707daa VK	197
	198	/**
	199	* dev_pm_opp_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with @cpu_dev
	200	* @cpu_dev: CPU device for which we do this operation
	201	* @cpumask: cpumask to update with information of sharing CPUs
	202	*
	203	* This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
	204	*
79ee2e8f VK	205	* Returns -ENODEV if OPP table isn't already present and -EINVAL if the OPP
79ee2e8f VK	206	* table's status is access-unknown.
6f707daa	207	*/
ddbb74bc	208	int dev_pm_opp_get_sharing_cpus(struct device cpu_dev, struct cpumask cpumask)
6f707daa VK	209	{
	210	struct opp_device *opp_dev;
	211	struct opp_table *opp_table;
	212	int ret = 0;
	213
6f707daa	214	opp_table = _find_opp_table(cpu_dev);
5b650b38 VK	215	if (IS_ERR(opp_table))
5b650b38 VK	216	return PTR_ERR(opp_table);
6f707daa	217
79ee2e8f VK	218	if (opp_table->shared_opp == OPP_TABLE_ACCESS_UNKNOWN) {
79ee2e8f VK	219	ret = -EINVAL;
5b650b38	220	goto put_opp_table;
79ee2e8f VK	221	}
79ee2e8f VK	222
6f707daa VK	223	cpumask_clear(cpumask);
6f707daa VK	224
79ee2e8f	225	if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
3d255699	226	mutex_lock(&opp_table->lock);
6f707daa VK	227	list_for_each_entry(opp_dev, &opp_table->dev_list, node)
6f707daa VK	228	cpumask_set_cpu(opp_dev->dev->id, cpumask);
3d255699	229	mutex_unlock(&opp_table->lock);
6f707daa VK	230	} else {
	231	cpumask_set_cpu(cpu_dev->id, cpumask);
	232	}
	233
5b650b38 VK	234	put_opp_table:
5b650b38 VK	235	dev_pm_opp_put_opp_table(opp_table);
6f707daa VK	236
	237	return ret;
	238	}
	239	EXPORT_SYMBOL_GPL(dev_pm_opp_get_sharing_cpus);