[SeaBIOS] [Qemu-devel] [PATCH 1/8] Support PCI based option rom loading
andreas.faerber at web.de
Sun Dec 20 19:24:48 CET 2009
Am 20.12.2009 um 19:01 schrieb Alexander Graf:
> On 20.12.2009, at 18:55, Anthony Liguori wrote:
>> Alexander Graf wrote:
>>> Don't macs usually have a powerpc vgabios?
>> I'm not certain, but this is what x86emu is for in X11.
>> VGA is a PC concept and just about nothing about it really make
>> sense on a different architecture. The interface is an extension
>> of the PC BIOS (software interrupts) and the dictated memory
>> layouts are specific to the x86. I think most non-x86 systems have
>> to use native drivers for whatever graphics cards they support from
>> the start.
> Yes. The Alpha for example used stock VGABIOSes. IIRC Sparc has its
> own graphics anyways and I don't know about the others, but I
> suspect they either use x86 VGABIOSes or no VGABIOSes.
> Macs are different though. IIRC they have a normal VGA interface in
> ppc logic, but I might be wrong. Maybe it's also some OpenFirmware
> stuff. They definitely don't have an x86 VGABIOS in the graphics
> card's rom slot, but something different.
> Since we're using the Cirrus on Macs, I guess we'd need a Cirrus PPC
> VGABIOS - phew.
ATI used to sell special "Mac Edition" graphics cards. That would seem
to back up the possibility of a ppc VGABIOS on Mac.
Never tried putting such a card into a PC though or vice versa. Maybe
we'd get the same sick-coloured penguins then...? ;)
> Other PPCs on the other hand, such as the Powerstation, use x86 roms.
> Oh well, let's just export the x86 one for now but use video.x for
> video output. Looks like there'd be quite a lot of work involved in
> getting it aligned to real world mac hw :-(.
> PS: Ben, please correct me if I'm wrong.
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