Il 10/12/2013 15:53, Gerd Hoffmann ha scritto: > Hi, > >> If we could make a small guset visible change, it would be simpler to >> always make the PCI hole 1GB in size; it is currently 256MB for i440FX >> and 1.25GB for q35. > > Easy for i440fx. > > Tricky for q35 as the firmware knows qemu will not map ram above > 0xb000000 and places the mmconfig bar @ 0xb0000000. Making the window > smaller (1.25GB -> 1GB) will create a conflict there. Making it larger > (2G) will work. It's done this way to keep 0xc0000000+ free for pci > bars, and we can map up to 512MB-sized bars there.
0xc0000000-0xfebfffff is almost 1GB, so there is room for 1 512MB-size BAR. mmconfig could move to 0xf0000000-0xf7ffffff; firmware is not a problem because this would be only for new machine types. Unless I'm missing something of course. Paolo >> We can take a look as soon as the SeaBIOS patches >> are in to use QEMU-built ACPI tables. > > This is in master already. > > cheers, > Gerd > >
