[coreboot] Intel Leaf Hill Coreboot Trouble

[Peter Stuge]

Hi Cameron,

Cameron Craig wrote:
> I have managed to create a bootable image using an out of date copy
> of coreboot and U-Boot, provided by Intel under NDA.

coreboot code is always covered by the GPL, regardless of where it came
from. If Intel tries to bind you in a contradictory agreement I don't
think that holds. Check with a lawyer.

I think U-Boot is GPL-licensed too.


> The stitching process used to generate the image is a little ugly:
> a set of Windows tools are provided (or pointed at) by Intel to
> stitch the various blobs together to create an 8MB image.  We would
> like to move away from this process.  Using the cbfs tool it looks
> like we are getting a legacy image composed entirely of a single
> CBFS.

What does a current cbfstool print output for that image?


> However, as far as I understand, the latest coreboot release (v4.6)
> should be capable of producing a 16MB working image without the use
> of external tools.

I would suggest reducing variables. So start with the same size. And
reuse as many bits and pieces (descriptors, blobs, etc.) as possible
from the working image.


> 4.       Extract Flash Descriptor from an existing Leaf Hill UEFI image (./ifdtool --extract leaf_hill_ref_board_uefi.bin)

What about the flash descriptor from the working forked coreboot build?


> Other than that, I currently have no working theories as to what
> the root cause is ☹

Firmware development is lots of fun! :)


> Is there anything obviously wrong with this process?

If the flash descriptors match and bar the added variables then no,
not really.


I would recommend to focus on increasing debug capability. If all
else fails then even looking at the SPI flash clock and data signals
with a scope or logic analyzer can be useful.

If there's a speaker on the board then you can try spkmodem. It's
noisy, but fun, and works early.


//Peter