Re: [Qemu-devel] [PATCH rebased for-1.8] i386: pc: align gpa<->hpa on 1GB boundary (v6)

[Gerd Hoffmann]

  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.

>   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