forked from Minki/linux
90ca2979ed
Entering and leaving WFI is really cheap so there's no reason to have much of a residency requirement for the state. Lower it to 1ms. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
92 lines
2.1 KiB
C
92 lines
2.1 KiB
C
/* linux/arch/arm/mach-s3c64xx/cpuidle.c
|
|
*
|
|
* Copyright (c) 2011 Wolfson Microelectronics, plc
|
|
* 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/kernel.h>
|
|
#include <linux/init.h>
|
|
#include <linux/cpuidle.h>
|
|
#include <linux/io.h>
|
|
#include <linux/export.h>
|
|
#include <linux/time.h>
|
|
|
|
#include <asm/proc-fns.h>
|
|
|
|
#include <mach/map.h>
|
|
|
|
#include <mach/regs-sys.h>
|
|
#include <mach/regs-syscon-power.h>
|
|
|
|
static int s3c64xx_enter_idle(struct cpuidle_device *dev,
|
|
struct cpuidle_driver *drv,
|
|
int index)
|
|
{
|
|
struct timeval before, after;
|
|
unsigned long tmp;
|
|
int idle_time;
|
|
|
|
local_irq_disable();
|
|
do_gettimeofday(&before);
|
|
|
|
/* Setup PWRCFG to enter idle mode */
|
|
tmp = __raw_readl(S3C64XX_PWR_CFG);
|
|
tmp &= ~S3C64XX_PWRCFG_CFG_WFI_MASK;
|
|
tmp |= S3C64XX_PWRCFG_CFG_WFI_IDLE;
|
|
__raw_writel(tmp, S3C64XX_PWR_CFG);
|
|
|
|
cpu_do_idle();
|
|
|
|
do_gettimeofday(&after);
|
|
local_irq_enable();
|
|
idle_time = (after.tv_sec - before.tv_sec) * USEC_PER_SEC +
|
|
(after.tv_usec - before.tv_usec);
|
|
|
|
dev->last_residency = idle_time;
|
|
return index;
|
|
}
|
|
|
|
static struct cpuidle_state s3c64xx_cpuidle_set[] = {
|
|
[0] = {
|
|
.enter = s3c64xx_enter_idle,
|
|
.exit_latency = 1,
|
|
.target_residency = 1,
|
|
.flags = CPUIDLE_FLAG_TIME_VALID,
|
|
.name = "IDLE",
|
|
.desc = "System active, ARM gated",
|
|
},
|
|
};
|
|
|
|
static struct cpuidle_driver s3c64xx_cpuidle_driver = {
|
|
.name = "s3c64xx_cpuidle",
|
|
.owner = THIS_MODULE,
|
|
.state_count = ARRAY_SIZE(s3c64xx_cpuidle_set),
|
|
};
|
|
|
|
static struct cpuidle_device s3c64xx_cpuidle_device = {
|
|
.state_count = ARRAY_SIZE(s3c64xx_cpuidle_set),
|
|
};
|
|
|
|
static int __init s3c64xx_init_cpuidle(void)
|
|
{
|
|
int ret;
|
|
|
|
memcpy(s3c64xx_cpuidle_driver.states, s3c64xx_cpuidle_set,
|
|
sizeof(s3c64xx_cpuidle_set));
|
|
cpuidle_register_driver(&s3c64xx_cpuidle_driver);
|
|
|
|
ret = cpuidle_register_device(&s3c64xx_cpuidle_device);
|
|
if (ret) {
|
|
pr_err("Failed to register cpuidle device: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
device_initcall(s3c64xx_init_cpuidle);
|