Re: [Qemu-devel] Release plan for 0.12.0

[Anthony Liguori]

Carl-Daniel Hailfinger wrote:
> On 02.10.2009 18:58, Jordan Justen wrote:
>   
> > On Fri, Oct 2, 2009 at 06:29, Anthony Liguori <address@hidden> wrote:
> >   
> >     
> > > So I think the best way forward is to hold off on UEFI in mainline until we
> > > can provide a single unified stack.
> > >     
> > >       
> > While it is true that a separate machine type could potentially be
> > viewed as increasing the testing requirements, I am not so sure.  If
> > QEMU has a UEFI+CSM solution, wouldn't we still have to test both UEFI
> > based OS boot and the CSM based legacy OS boot?
> >   
> >     
>
> Given that you can easily pack coreboot+SeaBIOS+UEFI into one ROM and
> have coreboot boot either SeaBIOS (BIOS interface) or UEFI (EFI
> interface), wouldn't that solve all problems in one go? You get an
> unified stack and don't have to mess around with different firmware
> files because coreboot can read in a Qemu machine config option (or
> NVRAM/CMOS) and select the interface based on that.
>   

If you want to to work seamlessly, you need to check for the EFI system 
partition to see whether it's an EFI capable OS and then fallback 
gracefully to SeaBIOS boot.

> The hardware init part would be identical for all variants, only the
> interface would differ. coreboot works now and has the benefit of
> supporting real hardware as well, so the difference between a setup
> inside Qemu and a setup on real hardware is minimal.
>   

Tianocore's OVMF project should provide all the required initialization 
for EFI on QEMU.

> The coreboot solution would also avoid converting SeaBIOS because
> SeaBIOS already works as coreboot payload (that's how coreboot
> developers call the CSM).
>   

I'll bite, what's the advantage of doing coreboot + SeaBIOS vs. SeaBIOS 
alone?  Forget about EFI for the moment, should be considering switching 
to coreboot + SeaBIOS for 0.12?

Regards,

Anthony Liguori