[U-Boot-Users] PPC4xx OF Flat Tree Support

[Darcy Watkins]

Hello,

I am investigating migration of our AMCC405EP embedded linux based
product from arch/ppc to arch/powerpc so that I can keep on top of real
time extensions and other things that have abandoned the arch/ppc tree.
I have just got to the point where I can compile linux kernel
2.6.24-rc3-git2 under arch/powerpc, but it will not boot.  Further
investigation leads to the boot process being different between the two
arch trees.

I read up on this open firmware (OF) flattened device tree (fdt) that
gets passed to the kernel and discover that there is no support for it
in the u-boot cpu support modules for the ppc4xx CPU family.

I know that there is work in progress going on out there to migrate the
Walnut (AMCC405GP) to arch/powerpc, and a new AMCC Kilauea board based
on the new AMCC405EX processor appears under arch/powerpc - but neither
of these appear to have board support or the OF fdt support in u-boot
yet.  I checked the latest release (1.3.0) and the git repository.

My requirement essential breaks out as follows:
 1.  I need OF fdt support for ppc4xx (at least I think I need it)
 2.  I need to implement a u-boot board support for our Taihushui board.
 3.  If possible, I would like to have u-boot be able to boot a linux
kernel
     built from either arch/ppc or arch/powerpc (with some form of
option in
     the bootm command to choose, or determine it from info in the
uImage).

If anyone has useful comments, suggestions and/or can point me to
work-in-progress, patches, etc that would help me further investigate
this, I'd appreciate it.

Thanks in advance!

Regards,

Darcy