linux/arch/arm/mach-imx/cpuidle-imx6q.c
Shawn Guo 8fb76a07e2 ARM: imx6: set initial power mode in pm function
Rather than setting initial low-power mode in every single i.MX6 clock
initialization function, we should really do that in pm code.  Let's
move imx6q_set_lpm(WAIT_CLOCKED) call into imx6_pm_common_init().

While at it, let's rename the function to imx6_set_lpm() since it's
actually common for all i.MX6 SoCs.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
2015-06-03 14:44:31 +08:00

72 lines
1.5 KiB
C

/*
* Copyright (C) 2012 Freescale Semiconductor, Inc.
*
* 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/module.h>
#include <asm/cpuidle.h>
#include "common.h"
#include "cpuidle.h"
#include "hardware.h"
static atomic_t master = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(master_lock);
static int imx6q_enter_wait(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
if (atomic_inc_return(&master) == num_online_cpus()) {
/*
* With this lock, we prevent other cpu to exit and enter
* this function again and become the master.
*/
if (!spin_trylock(&master_lock))
goto idle;
imx6_set_lpm(WAIT_UNCLOCKED);
cpu_do_idle();
imx6_set_lpm(WAIT_CLOCKED);
spin_unlock(&master_lock);
goto done;
}
idle:
cpu_do_idle();
done:
atomic_dec(&master);
return index;
}
static struct cpuidle_driver imx6q_cpuidle_driver = {
.name = "imx6q_cpuidle",
.owner = THIS_MODULE,
.states = {
/* WFI */
ARM_CPUIDLE_WFI_STATE,
/* WAIT */
{
.exit_latency = 50,
.target_residency = 75,
.flags = CPUIDLE_FLAG_TIMER_STOP,
.enter = imx6q_enter_wait,
.name = "WAIT",
.desc = "Clock off",
},
},
.state_count = 2,
.safe_state_index = 0,
};
int __init imx6q_cpuidle_init(void)
{
/* Set INT_MEM_CLK_LPM bit to get a reliable WAIT mode support */
imx6q_set_int_mem_clk_lpm(true);
return cpuidle_register(&imx6q_cpuidle_driver, NULL);
}