Il 24/09/2014 22:57, Alex Williamson ha scritto: > Right, that's the physical mapping, Andy's patches are mimicking that > behavior virtually. Seabios reserves memory, creates e820 entries, and > "maps" the hardware by writing to these registers. That triggers QEMU > to adjust the MemoryRegion in the guest address space which is an mmap > to the host address space, using /dev/mem for now, but hopefully the > vfio file descriptor in the future (I should be careful what I hope > for). Yeah, I remember discussing that with Andrew on IRC. So he did implement that idea. > The opregion is pretty trivial because the write is to the IGD itself. > The others are to the host bridge, so we need to figure out what sort of > abstraction makes sense to get that back into vfio code. Do we have to support all chipsets? IIUC the more recent devices need fewer and fewer "backdoors". Paolo > Perhaps vfio creates all the memory regions and registers them into an > igd service and the host bridge can make calls like: > > gtt = igd_get_gtt_mr(); > > which returns NULL and nothing happens or the registered MemoryRegion > and the host bridge places it into the address space. Thanks, _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
