[U-Boot] [POST] retrieving the results in Linux ?

[Wolfgang Denk]

Dear Valentin Longchamp,

In message <4E146E9F.4000705 at keymile.com> you wrote:
> 
> In the POST documentation, it is clearly stated:
> 
> > 2) The results of tests shall be saved so that it will be possible to
> >    retrieve them from Linux.
> 
> I have two questions here:
> 
> - I don't find where the result actually is saved. Was this implemented already
> ? Was the logbuffer intented for this (call to logbuff_log in post_log) ?

Yes.  The idea is to share the log buffer between U-Boot and Linux
(hence it's allocation at the very end of the RAM).  Of course you
need support for this feature in Linux, too.  IIRC this has not yet
made it's way into mainline.

> - If I was wrong for the first question (the results actually are saved), where
> can I find some information about how to retrieve these results ?

The plan is to share the log buffer, in both directions: Linux can
read the POST results, and U-Boot can read the last Linux messages
after a crash / reboot.  Actually, after a reboot you can read the
last messages from the _previously_ running kernel in Linux, too
(assuming there are no wraparounds, of course).

Best regards,

Wolfgang Denk

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