[coyotos-dev] Looking for ideas - image loading

[Jeroen C. Visser]

On Jan 29, 2008 11:17 AM, Jonathan S. Shapiro <shap at eros-os.com> wrote:
> I was looking for a solution that would work with ELF boot loaders and
> also with most of the cross-development loaders. Since almost all of
> them know how to load ELF these days (and if needed, ELF can be
> converted to SREC), I decided to add an ELF segment.
>
> In case it may suggest a useful approach for your future work, you may
> want to have a look at the script. The critical bits are:
>
>   1. Change in the kernel Makefile to produce coyotos.reloc.o, which
>      produces a fully resolved but not yet relocated kernel.
>
>   2. coymerge, which bundles the mkimage file into a .o, combines it
>      with coyotos.reloc.o, and executes the final, relocating link step
>      to produce the executable.

Thanks for breaking that down!

I originally settled on the concatenation hack because I couldn't
teach U-Boot to pass a command-line to Coyotos in less than 30 minutes
on my board. (I've since learned that this is a known U-Boot issue for
my board.)

This new approach is a lot better: one should now be able to fold a
well-formed Coyotos ELF image (kernel/ipl) into a single *compressed*
U-boot image file that will (net)boot on any recent *stock* U-Boot
install. (U-Boot has problems packaging standalone coyimage files
because it doesn't recognize the file format.)

Yay!

-JCV