Re: [PATCH] watchdog: imx_sc_wdt: Pretimeout should follow SCU firmware format

[Guenter Roeck]

On 10/9/19 12:37 AM, Anson Huang wrote:
> SCU firmware calculates pretimeout based on current time stamp
> instead of watchdog timeout stamp, need to convert the pretimeout
> to SCU firmware's timeout value.
>
> Fixes: 15f7d7fc5542 ("watchdog: imx_sc: Add pretimeout support")
> Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
>   drivers/watchdog/imx_sc_wdt.c | 8 +++++++-
>   1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/watchdog/imx_sc_wdt.c b/drivers/watchdog/imx_sc_wdt.c
> index 7ea5cf5..8ed89f0 100644
> --- a/drivers/watchdog/imx_sc_wdt.c
> +++ b/drivers/watchdog/imx_sc_wdt.c
> @@ -99,8 +99,14 @@ static int imx_sc_wdt_set_pretimeout(struct watchdog_device *wdog,
>   {
>   	struct arm_smccc_res res;
>   
> +	/*
> +	 * SCU firmware calculates pretimeout based on current time
> +	 * stamp instead of watchdog timeout stamp, need to convert
> +	 * the pretimeout to SCU firmware's timeout value.
> +	 */
>   	arm_smccc_smc(IMX_SIP_TIMER, IMX_SIP_TIMER_SET_PRETIME_WDOG,
> -		      pretimeout * 1000, 0, 0, 0, 0, 0, &res);
> +		      (wdog->timeout - pretimeout) * 1000, 0, 0, 0,
> +		      0, 0, &res);
>   	if (res.a0)
>   		return -EACCES;
>