linux/drivers/cpufreq/exynos-cpufreq.c

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/*
* Copyright (c) 2010-2011 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* EXYNOS - CPU frequency scaling support for EXYNOS series
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/regulator/consumer.h>
#include <linux/cpufreq.h>
#include <linux/platform_device.h>
#include <plat/cpu.h>
#include "exynos-cpufreq.h"
static struct exynos_dvfs_info *exynos_info;
static struct regulator *arm_regulator;
static unsigned int locking_frequency;
static int exynos_cpufreq_get_index(unsigned int freq)
{
struct cpufreq_frequency_table *freq_table = exynos_info->freq_table;
struct cpufreq_frequency_table *pos;
cpufreq_for_each_entry(pos, freq_table)
if (pos->frequency == freq)
break;
if (pos->frequency == CPUFREQ_TABLE_END)
return -EINVAL;
return pos - freq_table;
}
static int exynos_cpufreq_scale(unsigned int target_freq)
{
struct cpufreq_frequency_table *freq_table = exynos_info->freq_table;
unsigned int *volt_table = exynos_info->volt_table;
struct cpufreq_policy *policy = cpufreq_cpu_get(0);
unsigned int arm_volt, safe_arm_volt = 0;
unsigned int mpll_freq_khz = exynos_info->mpll_freq_khz;
unsigned int old_freq;
int index, old_index;
int ret = 0;
old_freq = policy->cur;
/*
* The policy max have been changed so that we cannot get proper
* old_index with cpufreq_frequency_table_target(). Thus, ignore
* policy and get the index from the raw frequency table.
*/
old_index = exynos_cpufreq_get_index(old_freq);
if (old_index < 0) {
ret = old_index;
goto out;
}
index = exynos_cpufreq_get_index(target_freq);
if (index < 0) {
ret = index;
goto out;
}
/*
* ARM clock source will be changed APLL to MPLL temporary
* To support this level, need to control regulator for
* required voltage level
*/
if (exynos_info->need_apll_change != NULL) {
if (exynos_info->need_apll_change(old_index, index) &&
(freq_table[index].frequency < mpll_freq_khz) &&
(freq_table[old_index].frequency < mpll_freq_khz))
safe_arm_volt = volt_table[exynos_info->pll_safe_idx];
}
arm_volt = volt_table[index];
/* When the new frequency is higher than current frequency */
if ((target_freq > old_freq) && !safe_arm_volt) {
/* Firstly, voltage up to increase frequency */
ret = regulator_set_voltage(arm_regulator, arm_volt, arm_volt);
if (ret) {
pr_err("%s: failed to set cpu voltage to %d\n",
__func__, arm_volt);
return ret;
}
}
if (safe_arm_volt) {
ret = regulator_set_voltage(arm_regulator, safe_arm_volt,
safe_arm_volt);
if (ret) {
pr_err("%s: failed to set cpu voltage to %d\n",
__func__, safe_arm_volt);
return ret;
}
}
exynos_info->set_freq(old_index, index);
/* When the new frequency is lower than current frequency */
if ((target_freq < old_freq) ||
((target_freq > old_freq) && safe_arm_volt)) {
/* down the voltage after frequency change */
ret = regulator_set_voltage(arm_regulator, arm_volt,
arm_volt);
if (ret) {
pr_err("%s: failed to set cpu voltage to %d\n",
__func__, arm_volt);
goto out;
}
}
out:
cpufreq_cpu_put(policy);
return ret;
}
cpufreq: Implement light weight ->target_index() routine Currently, the prototype of cpufreq_drivers target routines is: int target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); And most of the drivers call cpufreq_frequency_table_target() to get a valid index of their frequency table which is closest to the target_freq. And they don't use target_freq and relation after that. So, it makes sense to just do this work in cpufreq core before calling cpufreq_frequency_table_target() and simply pass index instead. But this can be done only with drivers which expose their frequency table with cpufreq core. For others we need to stick with the old prototype of target() until those drivers are converted to expose frequency tables. This patch implements the new light weight prototype for target_index() routine. It looks like this: int target_index(struct cpufreq_policy *policy, unsigned int index); CPUFreq core will call cpufreq_frequency_table_target() before calling this routine and pass index to it. Because CPUFreq core now requires to call routines present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time. This also marks target() interface as deprecated. So, that new drivers avoid using it. And Documentation is updated accordingly. It also converts existing .target() to newly defined light weight .target_index() routine for many driver. Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Russell King <linux@arm.linux.org.uk> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
2013-10-25 14:15:48 +00:00
static int exynos_target(struct cpufreq_policy *policy, unsigned int index)
{
return exynos_cpufreq_scale(exynos_info->freq_table[index].frequency);
}
static int exynos_cpufreq_cpu_init(struct cpufreq_policy *policy)
{
policy->clk = exynos_info->cpu_clk;
policy->suspend_freq = locking_frequency;
return cpufreq_generic_init(policy, exynos_info->freq_table, 100000);
}
static struct cpufreq_driver exynos_driver = {
.flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
.verify = cpufreq_generic_frequency_table_verify,
cpufreq: Implement light weight ->target_index() routine Currently, the prototype of cpufreq_drivers target routines is: int target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation); And most of the drivers call cpufreq_frequency_table_target() to get a valid index of their frequency table which is closest to the target_freq. And they don't use target_freq and relation after that. So, it makes sense to just do this work in cpufreq core before calling cpufreq_frequency_table_target() and simply pass index instead. But this can be done only with drivers which expose their frequency table with cpufreq core. For others we need to stick with the old prototype of target() until those drivers are converted to expose frequency tables. This patch implements the new light weight prototype for target_index() routine. It looks like this: int target_index(struct cpufreq_policy *policy, unsigned int index); CPUFreq core will call cpufreq_frequency_table_target() before calling this routine and pass index to it. Because CPUFreq core now requires to call routines present in freq_table.c CONFIG_CPU_FREQ_TABLE must be enabled all the time. This also marks target() interface as deprecated. So, that new drivers avoid using it. And Documentation is updated accordingly. It also converts existing .target() to newly defined light weight .target_index() routine for many driver. Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Russell King <linux@arm.linux.org.uk> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
2013-10-25 14:15:48 +00:00
.target_index = exynos_target,
.get = cpufreq_generic_get,
.init = exynos_cpufreq_cpu_init,
.name = "exynos_cpufreq",
.attr = cpufreq_generic_attr,
#ifdef CONFIG_ARM_EXYNOS_CPU_FREQ_BOOST_SW
.boost_supported = true,
#endif
#ifdef CONFIG_PM
.suspend = cpufreq_generic_suspend,
#endif
};
static int exynos_cpufreq_probe(struct platform_device *pdev)
{
int ret = -EINVAL;
exynos_info = kzalloc(sizeof(*exynos_info), GFP_KERNEL);
if (!exynos_info)
return -ENOMEM;
if (soc_is_exynos4210())
ret = exynos4210_cpufreq_init(exynos_info);
else if (soc_is_exynos4212() || soc_is_exynos4412())
ret = exynos4x12_cpufreq_init(exynos_info);
else if (soc_is_exynos5250())
ret = exynos5250_cpufreq_init(exynos_info);
else
return 0;
if (ret)
goto err_vdd_arm;
if (exynos_info->set_freq == NULL) {
pr_err("%s: No set_freq function (ERR)\n", __func__);
goto err_vdd_arm;
}
arm_regulator = regulator_get(NULL, "vdd_arm");
if (IS_ERR(arm_regulator)) {
pr_err("%s: failed to get resource vdd_arm\n", __func__);
goto err_vdd_arm;
}
/* Done here as we want to capture boot frequency */
locking_frequency = clk_get_rate(exynos_info->cpu_clk) / 1000;
if (!cpufreq_register_driver(&exynos_driver))
return 0;
pr_err("%s: failed to register cpufreq driver\n", __func__);
regulator_put(arm_regulator);
err_vdd_arm:
kfree(exynos_info);
return -EINVAL;
}
static struct platform_driver exynos_cpufreq_platdrv = {
.driver = {
.name = "exynos-cpufreq",
.owner = THIS_MODULE,
},
.probe = exynos_cpufreq_probe,
};
module_platform_driver(exynos_cpufreq_platdrv);