linux/drivers/cpuidle/cpuidle-exynos.c

144 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2011-2014 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* Coupled cpuidle support based on the work of:
* Colin Cross <ccross@android.com>
* Daniel Lezcano <daniel.lezcano@linaro.org>
*/
#include <linux/cpuidle.h>
#include <linux/cpu_pm.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/platform_data/cpuidle-exynos.h>
#include <asm/suspend.h>
#include <asm/cpuidle.h>
static atomic_t exynos_idle_barrier;
static struct cpuidle_exynos_data *exynos_cpuidle_pdata;
static void (*exynos_enter_aftr)(void);
static int exynos_enter_coupled_lowpower(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
int ret;
exynos_cpuidle_pdata->pre_enter_aftr();
/*
* Waiting all cpus to reach this point at the same moment
*/
cpuidle_coupled_parallel_barrier(dev, &exynos_idle_barrier);
/*
* Both cpus will reach this point at the same time
*/
ret = dev->cpu ? exynos_cpuidle_pdata->cpu1_powerdown()
: exynos_cpuidle_pdata->cpu0_enter_aftr();
if (ret)
index = ret;
/*
* Waiting all cpus to finish the power sequence before going further
*/
cpuidle_coupled_parallel_barrier(dev, &exynos_idle_barrier);
exynos_cpuidle_pdata->post_enter_aftr();
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);
exynos_enter_aftr();
return 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 = 10000,
.name = "C1",
.desc = "ARM power down",
},
},
.state_count = 2,
.safe_state_index = 0,
};
static struct cpuidle_driver exynos_coupled_idle_driver = {
.name = "exynos_coupled_idle",
.owner = THIS_MODULE,
.states = {
[0] = ARM_CPUIDLE_WFI_STATE,
[1] = {
.enter = exynos_enter_coupled_lowpower,
.exit_latency = 5000,
.target_residency = 10000,
.flags = CPUIDLE_FLAG_COUPLED |
CPUIDLE_FLAG_TIMER_STOP,
.name = "C1",
.desc = "ARM power down",
},
},
.state_count = 2,
.safe_state_index = 0,
};
static int exynos_cpuidle_probe(struct platform_device *pdev)
{
int ret;
if (IS_ENABLED(CONFIG_SMP) &&
(of_machine_is_compatible("samsung,exynos4210") ||
of_machine_is_compatible("samsung,exynos3250"))) {
exynos_cpuidle_pdata = pdev->dev.platform_data;
ret = cpuidle_register(&exynos_coupled_idle_driver,
cpu_possible_mask);
} else {
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",
},
};
builtin_platform_driver(exynos_cpuidle_driver);