[PATCH 1/1] watchdog: don't autostart watchdog on Sunxi boards

[Andre Przywara]

On Fri,  5 Nov 2021 19:34:31 +0100
Heinrich Schuchardt <heinrich.schuchardt at canonical.com> wrote:

> The Sunxi boards only support a 16 second watchdog timeout. This is too
> short to boot Linux. The UEFI specification requires 300 seconds as
> default timeout.

As detailed in this thread here [1], I would argue that
always keeping the watchdog running at all *after* U-Boot handed
off (either via booti/bootz/bootm or via ExitBootServices) sounds
questionable to me, especially when this wasn't the case so far.
The Linux kernel boot protocols (for arm and arm64) do not speak about
a watchdog, it would be interesting to see what's the expectation is
here.

Anyway we run into real issues with current HEAD, and be it for the
short period, so disabling it by default is the right way, at least for
now.

> Change the default for CONFIG_WATCHDOG_AUTOSTART for ARCH_SUNXI.
> 
> Fixes: b147bd3607f8 ("sunxi: Enable watchdog timer support by default")
> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>

Tested-by: Andre Przywara <andre.przywara at arm.com>

Cheers,
Andre

> ---
>  drivers/watchdog/Kconfig | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index d306054a8c..1177f17fd8 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -12,6 +12,7 @@ config WATCHDOG
>  config WATCHDOG_AUTOSTART
>  	bool "Automatically start watchdog timer"
>  	depends on WDT
> +	default n if ARCH_SUNXI
>  	default y
>  	help
>  	  Automatically start watchdog timer and start servicing it during