ARM: imx: add cpuidle support for i.mx6ul

This patch enables cpuidle driver for i.MX6UL, it
reuses i.MX6SX's cpuidle driver, 3 levels of cpuidle
supported:

1. ARM WFI;
2. SOC in WAIT mode;
3. SOC in WAIT mode + ARM power off.

As i.MX6UL has cortex-A7 CORE with an internal L2
cache, so flushing it before powering down ARM platform
is necessary, flush_cache_all() in last step of cpu_suspend
has very small overhead, just call it to avoid cache
type check for different platforms.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
This commit is contained in:
Anson Huang 2016-08-29 23:41:12 +08:00 committed by Shawn Guo
parent 6ae44aa651
commit 547e8f5269
2 changed files with 13 additions and 0 deletions

View file

@ -9,6 +9,7 @@
#include <linux/cpuidle.h>
#include <linux/cpu_pm.h>
#include <linux/module.h>
#include <asm/cacheflush.h>
#include <asm/cpuidle.h>
#include <asm/suspend.h>
@ -17,6 +18,15 @@
static int imx6sx_idle_finish(unsigned long val)
{
/*
* for Cortex-A7 which has an internal L2
* cache, need to flush it before powering
* down ARM platform, since flushing L1 cache
* here again has very small overhead, compared
* to adding conditional code for L2 cache type,
* just call flush_cache_all() is fine.
*/
flush_cache_all();
cpu_do_idle();
return 0;

View file

@ -16,6 +16,7 @@
#include <asm/mach/map.h>
#include "common.h"
#include "cpuidle.h"
static void __init imx6ul_enet_clk_init(void)
{
@ -79,6 +80,8 @@ static void __init imx6ul_init_irq(void)
static void __init imx6ul_init_late(void)
{
imx6sx_cpuidle_init();
if (IS_ENABLED(CONFIG_ARM_IMX6Q_CPUFREQ))
platform_device_register_simple("imx6q-cpufreq", -1, NULL, 0);
}