[PATCH] watchdog: Fix watchdog enablement in SPL and TPL

[Marek Vasut]

On 8/31/21 8:49 AM, Marcel Ziswiler wrote:
> Hi Marek
> 
> On Tue, 2021-08-31 at 00:03 +0200, Marek Vasut wrote:
>> Commit 830d29ac372 ("watchdog: Allow to use CONFIG_WDT without starting watchdog")
>> completely broke WDT operation in both SPL and TPL, in either case those
>> WDTs are never enabled. Fix it by filling in the missing Kconfig options
>> for SPL and TPL.
>>
>> Fixes: 830d29ac372 ("watchdog: Allow to use CONFIG_WDT without starting watchdog")
>> Signed-off-by: Marek Vasut <marex at denx.de>
>> Cc: Pali Rohar <pali at kernel.org>
>> Cc: Stefan Roese <sr at denx.de>
>> ---
>>   drivers/watchdog/Kconfig | 20 ++++++++++++++++++++
>>   1 file changed, 20 insertions(+)
>>
>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>> index f0ff2612a6b..65d974c4dd5 100644
>> --- a/drivers/watchdog/Kconfig
>> +++ b/drivers/watchdog/Kconfig
>> @@ -273,4 +273,24 @@ config SPL_WDT
>>            Enable driver model for watchdog timer in SPL.
>>            This is similar to CONFIG_WDT in U-Boot.
>>   
>> +config SPL_WATCHDOG_AUTOSTART
>> +       bool "Automatically start watchdog timer in SPL"
>> +       depends on SPL && WDT
>> +       default y
>> +       help
>> +         Automatically start watchdog timer and start servicing it during
>> +         SPL phase. Enabled by default. Disable this option if you want
>> +         to compile U-Boot with CONFIG_WDT support but do not want to
>> +         activate watchdog, like when CONFIG_WDT option is disabled.
>> +
>> +config TPL_WATCHDOG_AUTOSTART
>> +       bool "Automatically start watchdog timer in TPL"
>> +       depends on TPL && WDT
>> +       default y
>> +       help
>> +         Automatically start watchdog timer and start servicing it during
>> +         TPL phase. Enabled by default. Disable this option if you want
>> +         to compile U-Boot with CONFIG_WDT support but do not want to
>> +         activate watchdog, like when CONFIG_WDT option is disabled.
>> +
>>   endmenu
> 
> Those Kconfig entries look fine. However, I am wondering where exactly they get used. Am I missing anything?

Have a look at the patch this Fixes:, if those Kconfig entries are not 
present, the WDT is disabled in SPL and TPL unconditionally.

It could be that if you're using some non-free or proprietary preloader 
instead of SPL, you won't run into this problem.