[OE-core] Updating u-boot for oe-core or meta-yocto

[Richard Purdie]

I did a little research and I'd like to try and help us move forward.

The "problem" at the moment is both oe-core and meta-ti have u-boot
recipes. If Yocto were to merge in the meta-ti recipe to meta-yocto it
would overshadow the oe-core recipe. I believe Yocto wants to encourage
sharing a core on codebases like u-boot which are receptive and working
to facilitate collaboration (not unlike Yocto itself).

Valid questions are therefore:

a) What can we do to the u-boot recipe in core to make it customisable
from layers like meta-ti

b) Is it possible for the u-boot recipe in meta-ti to be a .bbappend
rather than a recipe which overwrites the default.

For a), I know Darren has some patches which drop the COMPATIBLE_MACHINE
usage for example and instead raise the skip parsing exception when
UBOOT_MACHINE isn't set which is a step in the right direction. If we
find other issues, lets fix them.

For b), I talked to Koen and he's going to see how feasible this is
although as always with this kind of issue there are various
complicating factors.

Hopefully if we work both sides of the problem we can get this resolved.
Darren, if you could send out some of your patches so far (e.g. for
COMPATIBLE_MACHINE) that might be helpful.

If the ultimate answer is that no, meta-ti has so many changes or
specific requirements that mean it needs to stay a .bb file then lets
cross that bridge if we come to it but I think this discussion makes
sense before reaching that conclusion. Its possible the last release of
u-boot has sufficient beagle support for yocto's needs and we could use
that instead.

Just on a more general note, the agreement on resolving the beagleboard
issue stands as is. The plan is to make beagleboard support in
meta-yocto as near a copy of the meta-ti pieces as possible with the
exception of the kernel where linux-yocto will import the needed patches
to demo the kernel tooling functionality. The layer tooling under
development will automate the process of syncing those pieces. I think
everyone is happy with the agreement and we just need to address some
corner cases like u-boot.

Cheers,

Richard