[PATCH v2 1/1] driver: watchdog: get platform clock from dt file

[Stefan Roese]

On 01.04.20 14:31, Rayagonda Kokatanur wrote:
> From: Bharat Kumar Reddy Gooty <bharat.gooty at broadcom.com>
> 
> Get the watchdog platform clock from the DTS file
> and use the same for calculating ticks in msec.
> 
> Signed-off-by: Bharat Kumar Reddy Gooty <bharat.gooty at broadcom.com>
> Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur at broadcom.com>
> ---
> Changes from v1:
>   -Address review comments from Stefan Roese,
>    Remove default timeout reading in probe() as it is read in include/wdt.h.
>    Add paranthesis on multi-line statements.

Looks much better, thanks. One comment still below...

>   drivers/watchdog/sp805_wdt.c | 13 +++++++++++--
>   1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
> index ca3ccbe76c..b9e4aee7a5 100644
> --- a/drivers/watchdog/sp805_wdt.c
> +++ b/drivers/watchdog/sp805_wdt.c
> @@ -34,6 +34,7 @@ DECLARE_GLOBAL_DATA_PTR;
>   
>   struct sp805_wdt_priv {
>   	void __iomem *reg;
> +	u32 clk_mhz;
>   };
>   
>   static int sp805_wdt_reset(struct udevice *dev)
> @@ -63,8 +64,13 @@ static int sp805_wdt_start(struct udevice *dev, u64 timeout, ulong flags)
>   	 * set 120s, the gd->bus_clk is less than 1145MHz, the load_value will
>   	 * not overflow.
>   	 */
> -	load_value = (gd->bus_clk) /
> -		(2 * 1000 * SYS_FSL_WDT_CLK_DIV) * load_time;
> +	if (gd->bus_clk) {
> +		load_value = (gd->bus_clk) /
> +			(2 * 1000 * SYS_FSL_WDT_CLK_DIV) * load_time;
> +	} else {
> +		/* platform provide clk */
> +		load_value = (timeout / 2) * (priv->clk_mhz / 1000);
> +	}
>   
>   	writel(UNLOCK, priv->reg + WDTLOCK);
>   	writel(load_value, priv->reg + WDTLOAD);
> @@ -110,6 +116,9 @@ static int sp805_wdt_ofdata_to_platdata(struct udevice *dev)
>   	if (IS_ERR(priv->reg))
>   		return PTR_ERR(priv->reg);
>   
> +	if (dev_read_u32(dev, "clk-mhz", &priv->clk_mhz))
> +		return -ENODATA;
> +

"clk-mhz" doesn't seem to be an official DT binding. Can't you use the
clk subsystem to get the base frequency of this device? On which
platform do you use the WDT driver btw?

Thanks,
Stefan