[U-Boot] [PATCH 4/4] udoo: fix watchdog setting

Giuseppe Pagano
2013-11-07T11:49:18Z

Hi Stefano,

On Thu, 2013-11-07 at 09:19 +0100, Stefano Babic wrote:
> Hi Giuseppe,
>
> On 06/11/2013 21:44, Giuseppe Pagano wrote:
> > To have watchdog quiet during kernel boot it is necessary to
> > change gpio wdt trigger direction.
> >
>
> Sorry, this is not a good explanation. You force a GPIO to drop a
> feture, instead of disabling the feature itself. And maybe some other
> people want to have this feature enabled.
>
> Which is the timeout for the watchdog ? Why is it hitting too soon ?
>
> Fix should be not done simply removing the effect, but checking the cause.

I know, my explanation was poor.
uDoo use APX823-31W5 as watchdog chip. Timeout is about 1.2 seconds.
To disabled watchdog during kernel boot, WDI pin of that chip needs to
be in "high impedance" state. As far as I known mx6 gpio configuration
does not contemplate tristate, so the option I choose is to set pin as
input and in "high impedance". If wdt gpio is leaved as output che chip
resets.

>
> Best regards,
> Stefano Babic
>

Best regards,
Giuseppe Pagano