There is no point to register the cpuidle driver for the 5440 as it has only one WFI state which is the default idle function when the cpuidle driver is disabled.
By disabling cpuidle we prevent to enter to the governor computation for nothing, thus saving a lot of processing time.
The only drawback is the statistic via sysfs on this state which is lost but it is meaningless and it could be retrieved from the ftrace easily.
Signed-off-by: Daniel Lezcano daniel.lezcano@linaro.org Reviewed-by: Tomasz Figa t.figa@samsung.com Acked-by: Amit Kucheria amit.kucheria@linaro.org --- arch/arm/mach-exynos/cpuidle.c | 3 --- arch/arm/mach-exynos/exynos.c | 3 +++ 2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c index ed7a439..d7091e0 100644 --- a/arch/arm/mach-exynos/cpuidle.c +++ b/arch/arm/mach-exynos/cpuidle.c @@ -133,9 +133,6 @@ static int exynos_cpuidle_probe(struct platform_device *pdev) { int ret;
- if (soc_is_exynos5440()) - exynos_idle_driver.state_count = 1; - ret = cpuidle_register(&exynos_idle_driver, NULL); if (ret) { dev_err(&pdev->dev, "failed to register cpuidle driver\n"); diff --git a/arch/arm/mach-exynos/exynos.c b/arch/arm/mach-exynos/exynos.c index b567361..fe8dac8 100644 --- a/arch/arm/mach-exynos/exynos.c +++ b/arch/arm/mach-exynos/exynos.c @@ -227,6 +227,9 @@ static struct platform_device exynos_cpuidle = {
void __init exynos_cpuidle_init(void) { + if (soc_is_exynos5440()) + return; + platform_device_register(&exynos_cpuidle); }