Commit 72b2fd5c authored by Linus Walleij's avatar Linus Walleij
Browse files

cpufreq: update DB8500 cpufreq driver 



This updates the ux500 cpufreq driver to the new interface from the
updated DB8500 PRCMU

Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: default avatarDave Jones <davej@redhat.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent 46936340

drivers/cpufreq/db8500-cpufreq.c

+63 −104
Original line number Diff line number Diff line 
/*

 * CPU frequency scaling for u8500

 * Inspired by linux/arch/arm/mach-davinci/cpufreq.c

 *

 * Copyright (C) STMicroelectronics 2009

 * Copyright (C) ST-Ericsson SA 2010

 *

 * License Terms: GNU General Public License v2

 *

 * Author: Sundar Iyer <sundar.iyer@stericsson.com>

 * Author: Martin Persson <martin.persson@stericsson.com>

 * Author: Jonas Aaberg <jonas.aberg@stericsson.com>

 *

 */



#include <linux/platform_device.h>

#include <linux/kernel.h>

#include <linux/cpufreq.h>

#include <linux/delay.h>

#include <linux/slab.h>

#include <linux/mfd/db8500-prcmu.h>



#include <mach/hardware.h>



#define DRIVER_NAME "cpufreq-u8500"

#define CPUFREQ_NAME "u8500"



static struct device *dev;

#include <mach/id.h>



static struct cpufreq_frequency_table freq_table[] = {

	[0] = {

		.index = 0,

		.frequency = 200000,

		.frequency = 300000,

	},

	[1] = {

		.index = 1,

		.frequency = 300000,

		.frequency = 600000,

	},

	[2] = {

		/* Used for MAX_OPP, if available */

		.index = 2,

		.frequency = 600000,

		.frequency = CPUFREQ_TABLE_END,

	},

	[3] = {

		/* Used for CPU_OPP_MAX, if available */

		.index = 3,

		.frequency = CPUFREQ_TABLE_END,

	},

	[4] = {

		.index = 4,

		.frequency = CPUFREQ_TABLE_END,

	},

};



static enum prcmu_cpu_opp index2opp[] = {

	CPU_OPP_EXT_CLK,

	CPU_OPP_50,

	CPU_OPP_100,

	CPU_OPP_MAX

static enum arm_opp idx2opp[] = {

	ARM_50_OPP,

	ARM_100_OPP,

	ARM_MAX_OPP

};



static struct freq_attr *db8500_cpufreq_attr[] = {

	&cpufreq_freq_attr_scaling_available_freqs,

	NULL,

};



static int u8500_cpufreq_verify_speed(struct cpufreq_policy *policy)

static int db8500_cpufreq_verify_speed(struct cpufreq_policy *policy)

{

	return cpufreq_frequency_table_verify(policy, freq_table);

}



static int u8500_cpufreq_target(struct cpufreq_policy *policy,

static int db8500_cpufreq_target(struct cpufreq_policy *policy,

				unsigned int target_freq,

				unsigned int relation)

{

	struct cpufreq_freqs freqs;

	unsigned int index;

	int ret = 0;

	unsigned int idx;



	/*

	 * Ensure desired rate is within allowed range.  Some govenors

	 * (ondemand) will just pass target_freq=0 to get the minimum.

	 */

	/* scale the target frequency to one of the extremes supported */

	if (target_freq < policy->cpuinfo.min_freq)

		target_freq = policy->cpuinfo.min_freq;

	if (target_freq > policy->cpuinfo.max_freq)

		target_freq = policy->cpuinfo.max_freq;



	ret = cpufreq_frequency_table_target(policy, freq_table,

					     target_freq, relation, &index);

	if (ret < 0) {

		dev_err(dev, "Could not look up next frequency\n");

		return ret;

	/* Lookup the next frequency */

	if (cpufreq_frequency_table_target

	    (policy, freq_table, target_freq, relation, &idx)) {

		return -EINVAL;

	}



	freqs.old = policy->cur;

	freqs.new = freq_table[index].frequency;

	freqs.new = freq_table[idx].frequency;

	freqs.cpu = policy->cpu;



	if (freqs.old == freqs.new) {

		dev_dbg(dev, "Current and target frequencies are equal\n");

	if (freqs.old == freqs.new)

		return 0;

	}



	dev_dbg(dev, "transition: %u --> %u\n", freqs.old, freqs.new);

	/* pre-change notification */

	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);



	ret = prcmu_set_cpu_opp(index2opp[index]);

	if (ret < 0) {

		dev_err(dev, "Failed to set OPP level\n");

		return ret;

	/* request the PRCM unit for opp change */

	if (prcmu_set_arm_opp(idx2opp[idx])) {

		pr_err("db8500-cpufreq:  Failed to set OPP level\n");

		return -EINVAL;

	}



	/* post change notification */

	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);



	return ret;

	return 0;

}



static unsigned int u8500_cpufreq_getspeed(unsigned int cpu)

static unsigned int db8500_cpufreq_getspeed(unsigned int cpu)

{

	int i;



	for (i = 0; prcmu_get_cpu_opp() != index2opp[i]; i++)

	/* request the prcm to get the current ARM opp */

	for (i = 0; prcmu_get_arm_opp() != idx2opp[i]; i++)

		;

	return freq_table[i].frequency;

}



static int __cpuinit u8500_cpu_init(struct cpufreq_policy *policy)

static int __cpuinit db8500_cpufreq_init(struct cpufreq_policy *policy)

{

	int res;

	int i;



	BUILD_BUG_ON(ARRAY_SIZE(index2opp) + 1 != ARRAY_SIZE(freq_table));

	BUILD_BUG_ON(ARRAY_SIZE(idx2opp) + 1 != ARRAY_SIZE(freq_table));



	if (cpu_is_u8500v2()) {

		freq_table[1].frequency = 400000;

		freq_table[2].frequency = 800000;

	if (cpu_is_u8500v2() && !prcmu_is_u8400()) {

		freq_table[0].frequency = 400000;

		freq_table[1].frequency = 800000;

		if (prcmu_has_arm_maxopp())

			freq_table[3].frequency = 1000000;

			freq_table[2].frequency = 1000000;

	}



	/* get policy fields based on the table */
@@ -136,13 +120,17 @@ static int __cpuinit u8500_cpu_init(struct cpufreq_policy *policy) 
	if (!res)

		cpufreq_frequency_table_get_attr(freq_table, policy->cpu);

	else {

		dev_err(dev, "u8500-cpufreq : Failed to read policy table\n");

		pr_err("db8500-cpufreq : Failed to read policy table\n");

		return res;

	}



	policy->min = policy->cpuinfo.min_freq;

	policy->max = policy->cpuinfo.max_freq;

	policy->cur = u8500_cpufreq_getspeed(policy->cpu);

	policy->cur = db8500_cpufreq_getspeed(policy->cpu);



	for (i = 0; freq_table[i].frequency != policy->cur; i++)

		;



	policy->governor = CPUFREQ_DEFAULT_GOVERNOR;



	/*
@@ -150,61 +138,32 @@ static int __cpuinit u8500_cpu_init(struct cpufreq_policy *policy) 
	 *	   function with no/some/all drivers in the notification

	 *	   list.

	 */

	policy->cpuinfo.transition_latency = 200 * 1000; /* in ns */

	policy->cpuinfo.transition_latency = 20 * 1000; /* in ns */



	/* policy sharing between dual CPUs */

	cpumask_copy(policy->cpus, &cpu_present_map);



	policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;



	return res;

}



static struct freq_attr *u8500_cpufreq_attr[] = {

	&cpufreq_freq_attr_scaling_available_freqs,

	NULL,

};

static int u8500_cpu_exit(struct cpufreq_policy *policy)

{

	cpufreq_frequency_table_put_attr(policy->cpu);

	return 0;

}



static struct cpufreq_driver u8500_driver = {

	.owner = THIS_MODULE,

static struct cpufreq_driver db8500_cpufreq_driver = {

	.flags  = CPUFREQ_STICKY,

	.verify = u8500_cpufreq_verify_speed,

	.target = u8500_cpufreq_target,

	.get = u8500_cpufreq_getspeed,

	.init = u8500_cpu_init,

	.exit = u8500_cpu_exit,

	.name = CPUFREQ_NAME,

	.attr = u8500_cpufreq_attr,

	.verify = db8500_cpufreq_verify_speed,

	.target = db8500_cpufreq_target,

	.get    = db8500_cpufreq_getspeed,

	.init   = db8500_cpufreq_init,

	.name   = "DB8500",

	.attr   = db8500_cpufreq_attr,

};



static int __init u8500_cpufreq_probe(struct platform_device *pdev)

static int __init db8500_cpufreq_register(void)

{

	dev = &pdev->dev;

	return cpufreq_register_driver(&u8500_driver);

}



static int __exit u8500_cpufreq_remove(struct platform_device *pdev)

{

	return cpufreq_unregister_driver(&u8500_driver);

}

	if (!cpu_is_u8500v20_or_later())

		return -ENODEV;



static struct platform_driver u8500_cpufreq_driver = {

	.driver = {

		.name	 = DRIVER_NAME,

		.owner	 = THIS_MODULE,

	},

	.remove = __exit_p(u8500_cpufreq_remove),

};



static int __init u8500_cpufreq_init(void)

{

	return platform_driver_probe(&u8500_cpufreq_driver,

				     &u8500_cpufreq_probe);

	pr_info("cpufreq for DB8500 started\n");

	return cpufreq_register_driver(&db8500_cpufreq_driver);

}



device_initcall(u8500_cpufreq_init);
 
device_initcall(db8500_cpufreq_register);