linux/arch/arm/mach-imx/cpuidle-imx6q.c
Daniel Lezcano 54a4644b7a ARM: imx: cpuidle: use init/exit common routine
The code intializes the cpuidle driver at different places.
The cpuidle driver for :
  * imx5 : is in the pm-imx5.c, the init function is in cpuidle.c
  * imx6 : is in cpuidle-imx6q.c, the init function is in cpuidle.c
           and cpuidle-imx6q.c

Instead of having the cpuidle code spread across different files,
let's create a driver for each SoC and use the common register function.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-23 13:45:23 +02:00

76 lines
1.7 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 <asm/proc-fns.h>
#include "common.h"
#include "cpuidle.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;
imx6q_set_lpm(WAIT_UNCLOCKED);
cpu_do_idle();
imx6q_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_TIME_VALID |
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)
{
/* Need to enable SCU standby for entering WAIT modes */
imx_scu_standby_enable();
/* Set chicken bit to get a reliable WAIT mode support */
imx6q_set_chicken_bit();
return cpuidle_register(&imx6q_cpuidle_driver, NULL);
}