On 07/21/15 14:08, Alexander Graf wrote: > On 07/20/15 21:06, Laszlo Ersek wrote: >> Cc'ing Alex >> >> On 07/13/15 12:15, Paolo Bonzini wrote: >>> >>> On 13/07/2015 09:32, Gerd Hoffmann wrote: >>>>> and virtio-vga is only compiled on 64-bit Intel? >>>> There is virtio-gpu-pci ... >>>> >>>> Any specific reason why we need vga compatibility on !x86? >>> I was actually thinking about 32-bit x86. :) I agree that !x86 is not >>> necessary. >> I disagree :) >> >> (This is actually my more important followup to this thread; the other >> message I just couldn't resist sending.) >> >> Gerd recently contributed virtio-vga support to OvmfPkg/QemuVideoDxe: >> >> https://github.com/tianocore/edk2/commit/94210dc9 >> >> That support depends on vga compat. All fine. >> >> What's probably not obvious is that I had ported >> PcAtChipsetPkg/PciHostBridgeDxe to ArmVirtPkg -- which drives Alex's >> generic PCIe host bridge, exposed on qemu-system-(arm|aarch64) -M virt >> -- and included OvmfPkg/QemuVideoDxe in the ArmVirtQemu.dsc build too. >> >> That means you can currently stick a -device VGA into -M virt, and it >> will work. Since OvmfPkg/QemuVideoDxe recognizes virtio-vga (see edk2 > > For some definition of work, yes :). It will work perfectly fine with > TCG, you will run into cache coherency problems with KVM because the > guest maps MMIO regions (like the vram) as uncached while QEMU accesses > it as cached.
Yes, I'm aware, I just didn't want to drag that thread into this discusson as well ;) > >> 94210dc9 again), and the driver is included by ArmVirtQemu.dsc, I think >> it would be probably useful to build the device model for arm/aarch64 >> targets too. >> >> See also QEMU commit 332261de2b (together with its parent commits). > > I agree. Also, as far as I understood Marc, his hope was that the fix to > halfway working VGA emulation would be virtio-gpu. Not sure how (if!) we're going to be able to drive that from the firmware! :) Thanks Laszlo
