Hi Piotr,
Piotr Brostovski wrote:
I used the tools mknbi and wraplinux for making an NBI or elf image from the kernel.
..
Do anyone have an idea why this doesn't work?
Yes.
As you know, both mknbi and wraplinux add some glue to the Linux kernel binary to turn it into a "boot image."
That glue relies on BIOS interrupt services however, and coreboot does not provide any such services by design.
Instead, you can use mkelfImage. It isn't really maintained anymore but we're making it available from the coreboot.org repo.
The glue added by mkelfImage does not rely on BIOS interrupt services and it is indeed the old-and-tried way of starting Linux from coreboot.
http://coreboot.org/Mkelfimage
Note the comment on that page about using vmlinux as payload directly. If you have a chance to test that, please let us know the result!
//Peter