[PATCH u-boot-mvebu 3/3] arm: mvebu: turris_omnia: disable MCU watchdog in SPL when booting over UART

[Stefan Roese]

On 16.08.21 15:11, Marek Behún wrote:
> On Mon, 16 Aug 2021 15:07:33 +0200
> Stefan Roese <sr at denx.de> wrote:
> 
>> So the MCU watchdog is some kind of very early WD and only used until
>> the SoC WD is used / enabled?
> 
> Yes, this is how it was first thought of for Omnia. Looking at the MCU
> code it seems that the watchdog can be started again after being
> disabled, so it could theoretically be used as a normal watchdog. The
> problem is that it cannot be pinged to reset the counter. It has to be
> stopped and started again, meaning there is a small window when it is
> disabled. If the system used this watchdog, this small window would
> make it vulnerable, so I don't think we should use it.

Agreed. With such a WD concept including this "window of vulnerability",
it really shouldn't be used.

Thanks,
Stefan

>>> Shall I resend this series with this new patch?
> 
>> Yes, please do.
> 
> Will do.
> 
> Marek
> 


Viele Grüße,
Stefan

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