[PATCH 1/3] clk: exynos5250: save/restore EPLL0 configuration

Tomasz Figa tomasz.figa at gmail.com
Sun Nov 10 12:01:28 EST 2013


Hi Sachin, Andrew,

On Friday 08 of November 2013 15:44:06 Sachin Kamat wrote:
> From: Andrew Bresticker <abrestic at chromium.org>
> 
> The EPLL configuration register needs to be saved across
> suspend/resume.
> 
> Signed-off-by: Andrew Bresticker <abrestic at chromium.org>
> Signed-off-by: Sachin Kamat <sachin.kamat at linaro.org>
> ---
>  drivers/clk/samsung/clk-exynos5250.c |    1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/clk/samsung/clk-exynos5250.c b/drivers/clk/samsung/clk-exynos5250.c
> index ee866e377c80..6767635dc895 100644
> --- a/drivers/clk/samsung/clk-exynos5250.c
> +++ b/drivers/clk/samsung/clk-exynos5250.c
> @@ -143,6 +143,7 @@ static unsigned long exynos5250_clk_regs[] __initdata = {
>  	SRC_CPU,
>  	DIV_CPU0,
>  	SRC_CORE1,
> +	EPLL_CON0,

What about EPLL_CON1 and EPLL_CON2? Also, have you considered register
restoration order?

Anyway, I believe it's not the correct way to restore PLL configuration.
See my Samsung PM consolidation series, especially patch [1] to see my
proposed way of handling this. (Beware of a bug that snuck into this patch
 - samsung_clk_save() is not being called for PLL registers.)

[1] http://thread.gmane.org/gmane.linux.kernel.samsung-soc/24078/focus=24087

Best regards,
Tomasz




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