Glauber Costa wrote:
On Wed, 2011-05-04 at 00:02 +0200, Sebastian Herbszt wrote:
Anthony Liguori wrote:
On 05/03/2011 03:23 PM, Sebastian Herbszt wrote:
Glauber Costa wrote:
It is theorectically possible for a system to have more than one pci vga card. In particular, I am interested in the use of SGAbios as a pci device, alongside of a normal vga bios in QEMU.
Can't SGAbios be loaded as an option rom without this change?
But then you're loading it as a legacy ROM which is fairly ugly and requires additional SeaBIOS hackery.
Why is this ugly and which additional hackery does it need? SGAbios is a legacy ROM; the PNP header is disabled and there is no PCIR.
It is, but does not need to be (I've also patched sgabios to include a PCIR). Since it is a device, it is nice to have it plugged it to a bus. If for nothing else, for discovering capabilities - A guest using sgabios this way is now aware that it has a double-head system.
I don't think "it is a device", more likely a functionality. SGAbios doesn't add a new device/hardware to the system. Do you plan to add a new (emulated) PCI device and deploy SGAbios thru its BAR? Do you plan to add support for "Google Memory Console"?
Also, let us not focus only in the specifics: Having two pci vga cards is a real possibility, there's even a use case for that, as anthony mentioned.
If you call the init function of two vga roms, will the last one win and hook int 10h?
Sebastian