[SeaBIOS] [PATCHv2] coreboot: Try to auto-detect if the CBFS anchor pointer is a relative pointer

Kevin O'Connor kevin at koconnor.net
Tue Jul 14 20:38:01 CEST 2015

On Wed, Jul 08, 2015 at 06:02:32PM -0700, Julius Werner wrote:
> I guess this heuristic should be very unlikely to fail with the
> current cbfstool implementation, so I'd be fine with it (at least as
> long as SeaBIOS is x86-only... non-x86 CBFS put the header close to
> the start address instead).
> Still, is anyone except Chrome OS actually using CONFIG_CBFS_LOCATION
> and absolute offsets?

Thanks for reviewing.  SeaBIOS is x86 only.  As far as I know only the
Chrome machines use CONFIG_CBFS_LOCATION.

>Because we have completely switched over now,
> and the absolute offset was hacked in as part of our SeaBIOS build
> script which is now updated, so at least with our SDK you can't really
> build a new SeaBIOS with the old-style absolute offset unless you
> intentionally revert some stuff. If there's no other system out there
> that still relies on absolute offsets, I'd suggest to just switch over
> to the new relative style completely.

That's a good point.

There are a couple of people building Chromebox roms though, and I'm a
little leery of breaking their pre-existing build scripts.  (Syching
the build scripts with a particular SeaBIOS commit is annoying for
those just wishing to try out the latest build.)

So, I'm inclined to commit this hack, but view it as something that
can get removed in a year or so.

Thanks again,

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