[U-Boot] [PATCH] wandboard: add pxe support, set default boot command like highbank

[Otavio Salvador]

On Tue, Aug 6, 2013 at 1:22 PM, Dennis Gilmore <dennis at ausil.us> wrote:
...
> My issue with this is, we produce a unified image, it could be an
> installer image or a installed disk image. it has a unified kernel in
> it and can run on any number of soc's but we also need to provide
> tooling that will setup the u-boot image so that it can be loaded by
> different boards. be it copying files into place or dding the binary
> into some offset. it kills the portability. i can't pull a sdcard from
> one board with one type of soc and plug it into another and have it
> just boot.

U-Boot is the hardest part of whole chain to make it cross SoC (and
cross Vendor SoC is even harder) as it needs to set pins and registers
which vary from one to another. So even using DeviceTree there I am
not aware of a way to make it to work for i.MX6 and Allwinner SoCs
without using different binaries. You can certainly share the binary
among different boards of same SoC (or SoC family) but across them I
am not aware of it being possible.

>> > > U-Boot is perfectly able to import such settings from text files
>> > > (or text blobs stored somewhere, even attached to the U-Boot
>> > > image, if you want), so just use the text files separately,
>> > > instead of hard compiling them into the code.
>> >
>> > In my case, I don't want to compile the environment into u-boot. But
>> > some people do as I copied my scripts from Tegra which has them
>> > built-in. Since built-in is C and standalone is text file, sharing
>> > is impossible. That is the main thing I'd like to see changed.
>> > Whether we support merging builtin and standalone envs is secondary.
>>
>> Who says "impossible" here?  When using a file system with write
>> support, you can use "env export -t" to create a text representation
>> and write it out to the file system (or store it in some reserved area
>> on some storage device).
> Exactly what i want to avoid. I really do want it compiled into the
> binary. because then I only have to put one file into place. on those
> systems needing it.
>
> another solution for me would be a unified u-boot that runs on all
> soc's and all boards. Everytime we have to do something different for a
> board or soc family is a step away from having something truly
> universal and portable.

What Wolfgang is saying here is it will still be a single file but
made in two steps. One U-Boot binary, another cluing the environment
to it.
...

Regards,

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://projetos.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750