[U-Boot] environment expectations of config_distro_bootcmd.h

[Ian Campbell <ijc@hellion.org.uk>]

On Mon, 2014-09-29 at 14:33 -0300, Otavio Salvador wrote:
> On Mon, Sep 29, 2014 at 2:17 PM, Stephen Warren <swarren@wwwdotorg.org> wrote:
> > On 09/28/2014 08:30 AM, Ian Campbell wrote:
> >>
> >> Is there any documentation as to what environment variables a platform
> >> must provide if it uses config_distro_bootcmd.h. ${scriptaddr} seems
> >> clear but what about e.g. kernel_addr_r and friends? I suppose the use
> >> of the pxe commands has some implicit dependencies (pxe_addr_r?)
> >>
> >> Along the same lines is there any documentation regarding which
> >> variables a boot.scr which expects to be called via this mechanism can
> >> rely on. e.g. devtype/devnum/bootpart/prefix etc. Also foo_addr_r again
> >> I suppose?
> >>
> >> There is some info in the README but it says things like "these
> >> variables don't have to be defined for all boards" and worse "some
> >> boards use these variables for other purposes." ;-)
> >
> >
> > Dennis did write the following when he first sent the patch to create
> > include/config_distro_bootcmd.h:
> >
> > http://patchwork.ozlabs.org/patch/332412/
> > [U-Boot,1/6] add README.distro file

Looks pretty good to me.

> > However, I only cleaned up and resent patch 2 in that series:
> >
> > http://patchwork.ozlabs.org/patch/332413/
> > [U-Boot,2/6] add header with a generic set of boot commands defined.
> >
> > ... so the README isn't in place at present.
> 
> Could you or Dennis update it to current tree and send a patch adding
> it? I think it is a must have so we easy the migration/adoption of it
> on more and more boards.

Yes, that would be great.

Personally I'd be inclined to suggest going with the doc as posted first
and updating the advise later once agreement is reach what the advise
should be, but at least until then we'd have the list of variables etc.

Ian.