[PATCH] ARM: AM43xx: clk: Change the wdt1 func clk src to per_32k clk
Tero Kristo
t-kristo at ti.com
Tue Apr 22 03:06:37 PDT 2014
On 04/16/2014 07:14 AM, Lokesh Vutla wrote:
> WDT1 module can take one of the below clocks as input functional
> clock -
> - On-Chip 32K RC Osc [default/reset]
> - 32K from PRCM
>
> The On-Chip 32K RC Osc clock is not an accurate clock-source as per
> the design/spec, so as a result, for example, timer which supposed
> to get expired @60Sec, but will expire somewhere ~@40Sec, which is
> not expected by any use-case.
>
> The solution here is to switch the input clock-source to PRCM
> generated 32K clock-source during boot-time itself.
> This is derived from AM33xx clock file.
I guess this patch should wait until we have a proper solution upstream
for selecting parents based on DT data, unless you have pressing need to
merge this as a temporary hack.
-Tero
>
> Signed-off-by: Lokesh Vutla <lokeshvutla at ti.com>
> ---
> drivers/clk/ti/clk-43xx.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/drivers/clk/ti/clk-43xx.c b/drivers/clk/ti/clk-43xx.c
> index 67c8de5..ae2524e 100644
> --- a/drivers/clk/ti/clk-43xx.c
> +++ b/drivers/clk/ti/clk-43xx.c
> @@ -110,9 +110,22 @@ static struct ti_dt_clk am43xx_clks[] = {
>
> int __init am43xx_dt_clk_init(void)
> {
> + struct clk *clk1, *clk2;
> +
> ti_dt_clocks_register(am43xx_clks);
>
> omap2_clk_disable_autoidle_all();
>
> + /*
> + * The On-Chip 32K RC Osc clock is not an accurate clock-source as per
> + * the design/spec, so as a result, for example, timer which supposed
> + * to get expired @60Sec, but will expire somewhere ~@40Sec, which is
> + * not expected by any use-case, so change WDT1 clock source to PRCM
> + * 32KHz clock.
> + */
> + clk1 = clk_get_sys(NULL, "wdt1_fck");
> + clk2 = clk_get_sys(NULL, "clkdiv32k_ick");
> + clk_set_parent(clk1, clk2);
> +
> return 0;
> }
>
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