[U-Boot] OMAP watchdog timer reset on BBB

[Sam Protsenko]

Hi Stefan,

On Thu, Sep 12, 2019 at 5:38 PM Stefan Roese <sr at denx.de> wrote:
>
> Hi Sam,
>
> On 12.09.19 15:45, Sam Protsenko wrote:
> > Hi Suniel,
> >
> > After transition to DM WDT, watchdog timer on BeagleBone Black resets
> > the board after 1 minute or so. I'm using this defconfig: [1]. After
> > disabling CONFIG_WDT and CONFIG_WATCHDOG options the board doesn't
> > reset. I guess it might be happening on other boards using
> > CONFIG_WDT_OMAP3 as well. The issue can be reproduced by stopping in
> > U-Boot shell (=>) and waiting for 1 minute.
> >
> > Do you know by chance why it might be happening, or maybe some fix
> > already exists?
> >
> > Thanks!
> >
> > [1] https://pastebin.ubuntu.com/p/Zz5bY6cYXS/
>
> So you have enabled the watchdog and should see something like this
> upon bootup:
>
> WDT:   Started without servicing (60s timeout)
>
> Is this correct? Then you need to enable the U-Boot internal WDT
> servicing by enabling CONFIG_WATCHDOG as well, as this will
> result in the internal U-Boot servicing of the watchdog. Then
> you should see this upon bootup and no reset will appear in
> U-Boot:
>
> WDT:   Started with servicing (60s timeout)
>

I'm seeing this ("with servicing") line, and CONFIG_WATCHDOG is
already enabled in am335x_evm_defconfig. So I think it's an issue,
which *probably* appeared when watchdog drivers were converted to
Driver Model (this defconfig is using CONFIG_WDT + CONFIG_WDT_OMAP3
options). Any clues what can be wrong?

> Does this help?
>
> Thanks,
> Stefan