Re: Reset on Beaglebone Black has become unreliable/broken

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hello Konstantin,

On 07.01.25 14:12, Konstantin Kletschke wrote:
> On Tue, Jan 07, 2025 at 12:17:03PM +0100, Ahmad Fatoum wrote:
> Should add a delay of 1.8ms. Is this feasible?

Sounds ok to me. Please send a patch to that effect with an explanatory
comment, summarizing what hardware was observed to have what issues.

>> If it's indeed just a millisecond, I am in favor of adding this to
>> barebox upstream with a comment explaining what this fixes, even
>> if we don't fully understand it yet.
> 
> Yes, I agree to the not fully yet understood part.
> What me holds back from lowering the speed is the following:
> 
> I went into production with the final result part above and reflashe all
> our BBB devices which failed warm start without the additional delay and
> all passed 100% flawlessly after the modficication. So it is tested upon
> roughly 30 devices which failed before.

I am surprised you are still shipping new products with a Beaglebone Black,
but anyhow, we need to be pragmatic and a ~2ms delay, even if not completely
understood is an acceptable price to pay for barebox reliably starting up
on newly produced BBBs.

Cheers,
Ahmad

> 
> Kind Regards
> Konstantin
> 
> 
> 


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