[coreboot] [Qemu-devel] Release plan for 0.12.0

Anthony Liguori anthony at codemonkey.ws
Mon Oct 5 15:51:57 CEST 2009

Carl-Daniel Hailfinger wrote:
> What about SeaBIOS + CSM (based on DUET)?

That's not quite the same thing.

In EFI, CSM is a specification that defines how to port a legacy BIOS 
such that it runs as basically an EFI module providing the old legacy 
BIOS interfaces that OSes support.  If you have a set of legacy option 
roms and efi modules, it defines how all of those things interact with 
each other to provide a consistent experience.

It's is not at all the same as just switching between EFI and BIOS.  
It's much more tightly integrated than that.

> I can't speak for Patrick, but he probably was concerned about making
> EFI the default with BIOS as fallback instead of the other way round.
> Forcing any EFI capable (or semi-capable) OS to be booted with EFI
> instead of leaving the choice in the hand of the user (NVRAM) or picking
> the sane default (what almost all boards out there are doing) sounds
> like a non-sustainable way for Qemu.

Why?  As long as it Just Works, I don't think it will ever even cross a 
users mind.

>> We'll be stuck with legacy option roms for a long, long time.  But I
>> also expect there will be a few devices out there that only provide
>> EFI modules.
> I expect that it will be some time before we see such devices (maybe
> only at trade show demos if at all). It will start to get interesting
> once such EFI modules have to interact with classic option ROMs.

I think at the high end, we'll see these sooner than you think.


Anthony Liguori

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