[LinuxBIOS] Interest in a Free Software BIOS for Radeon cards?

Oliver McFadden z3ro.geek at gmail.com
Sun Dec 9 23:47:02 CET 2007


I'm interested in a free software BIOS for the newer Radeon cards which use the
AtomBIOS format. The previous legacy BIOS is completely x86 assembly code unique
to each card, but the AtomBIOS is modular and *should* be easier to replace. I
haven't really done any serious work on this yet, and it's just a spare time
project (which isn't very much because of other projects and real life) but
there seems to be some interest.

There is some information on my blog (http://olivermcfadden.livejournal.com/)
trying to figure out how to flash these cards, but I think it's some kind of
GPIO based SPI interface.

AMD have released some register information for the Radeon cards
(http://www.x.org/docs/AMD/42589_rv630_rrg_1.01o.pdf and
http://www.x.org/docs/AMD/RRG-216M56-03oOEM.pdf) and a working AtomBIOS parser
in the radeonhd driver

I believe the parser in radeonhd is also compiled into the BIOS flashed to the
card. I guessed this from some left over preprocessor defines, etc.

As far as I know, the AtomBIOS on the card consists of an interpreter in x86
code, some binary scripts executed by the interpreter, and some data tables, all
wrapped up inside the PCI expansion ROM format.

The opcodes and format of the binary scripts and data tables are described by
the parser code, so I think there is enough information, except for how to
actually flash the on-card ROM...

I don't whether there is much interest for this project, but at least one
LinuxBIOS developer seems interested, so let's see where it goes...

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