linux/drivers/cpuidle/cpuidle-exynos.c

100 lines
2.1 KiB
C

/* linux/arch/arm/mach-exynos/cpuidle.c
*
* Copyright (c) 2011 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* 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/cpuidle.h>
#include <linux/cpu_pm.h>
#include <linux/export.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <asm/proc-fns.h>
#include <asm/suspend.h>
#include <asm/cpuidle.h>
static void (*exynos_enter_aftr)(void);
static int idle_finisher(unsigned long flags)
{
exynos_enter_aftr();
cpu_do_idle();
return 1;
}
static int exynos_enter_core0_aftr(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
cpu_pm_enter();
cpu_suspend(0, idle_finisher);
cpu_pm_exit();
return index;
}
static int exynos_enter_lowpower(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
int new_index = index;
/* AFTR can only be entered when cores other than CPU0 are offline */
if (num_online_cpus() > 1 || dev->cpu != 0)
new_index = drv->safe_state_index;
if (new_index == 0)
return arm_cpuidle_simple_enter(dev, drv, new_index);
else
return exynos_enter_core0_aftr(dev, drv, new_index);
}
static struct cpuidle_driver exynos_idle_driver = {
.name = "exynos_idle",
.owner = THIS_MODULE,
.states = {
[0] = ARM_CPUIDLE_WFI_STATE,
[1] = {
.enter = exynos_enter_lowpower,
.exit_latency = 300,
.target_residency = 100000,
.flags = CPUIDLE_FLAG_TIME_VALID,
.name = "C1",
.desc = "ARM power down",
},
},
.state_count = 2,
.safe_state_index = 0,
};
static int exynos_cpuidle_probe(struct platform_device *pdev)
{
int ret;
exynos_enter_aftr = (void *)(pdev->dev.platform_data);
ret = cpuidle_register(&exynos_idle_driver, NULL);
if (ret) {
dev_err(&pdev->dev, "failed to register cpuidle driver\n");
return ret;
}
return 0;
}
static struct platform_driver exynos_cpuidle_driver = {
.probe = exynos_cpuidle_probe,
.driver = {
.name = "exynos_cpuidle",
.owner = THIS_MODULE,
},
};
module_platform_driver(exynos_cpuidle_driver);