OpenCloudOS-Kernel/arch/arm/mach-at91/cpuidle.c

69 lines
1.6 KiB
C

/*
* based on arch/arm/mach-kirkwood/cpuidle.c
*
* CPU idle support for AT91 SoC
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*
* The cpu idle uses wait-for-interrupt and RAM self refresh in order
* to implement two idle states -
* #1 wait-for-interrupt
* #2 wait-for-interrupt and RAM self refresh
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/cpuidle.h>
#include <linux/io.h>
#include <linux/export.h>
#include <asm/proc-fns.h>
#include <asm/cpuidle.h>
#include <mach/cpu.h>
#include "pm.h"
#define AT91_MAX_STATES 2
/* Actual code that puts the SoC in different idle states */
static int at91_enter_idle(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
if (cpu_is_at91rm9200())
at91rm9200_standby();
else if (cpu_is_at91sam9g45())
at91sam9g45_standby();
else if (cpu_is_at91sam9263())
at91sam9263_standby();
else
at91sam9_standby();
return index;
}
static struct cpuidle_driver at91_idle_driver = {
.name = "at91_idle",
.owner = THIS_MODULE,
.states[0] = ARM_CPUIDLE_WFI_STATE,
.states[1] = {
.enter = at91_enter_idle,
.exit_latency = 10,
.target_residency = 10000,
.flags = CPUIDLE_FLAG_TIME_VALID,
.name = "RAM_SR",
.desc = "WFI and DDR Self Refresh",
},
.state_count = AT91_MAX_STATES,
};
/* Initialize CPU idle by registering the idle states */
static int __init at91_init_cpuidle(void)
{
return cpuidle_register(&at91_idle_driver, NULL);
}
device_initcall(at91_init_cpuidle);