[SeaBIOS] [Qemu-devel] [RESEND PATCH v2] pciinit: Enable default VGA device

Alex Williamson alex.williamson at redhat.com
Wed Mar 20 06:45:26 CET 2013

On Tue, 2013-03-19 at 22:52 -0600, Alex Williamson wrote:
> On Tue, 2013-03-19 at 19:08 -0400, Kevin O'Connor wrote:
> > On Mon, Mar 18, 2013 at 09:07:21PM -0600, Alex Williamson wrote:
> > > As QEMU gains PCI bridge and PCIe root port support, we won't always
> > > find the VGA device on the root bus.  We therefore need to add support
> > > to find and enable a VGA device and the path to it through the VGA
> > > Enable support in the PCI bridge control register.
> > 
> > Thanks.  I'm okay with the change.  It would be nice if someone more
> > familiar with the QEMU side could ack this patch.
> > 
> > As a minor nitpick - there is a pci_config_maskw() that would simplify
> > your code.
> Ah, that does clean it up a bit.  Actually, hold off on this patch.  I'm
> getting VGA routing setup as I expect, but guests are not happy with the
> other apertures on the bridges and I'm not sure if I'm contributing to
> that problem yet.  Thanks,

Turns out it's this:

commit 76e58028d28e78431f9de3cee0b3c88d807fa39d
Author: Kevin O'Connor <kevin at koconnor.net>
Date:   Wed Mar 6 21:50:09 2013 -0500

    acpi: Eliminate BDAT parameter passing to DSDT code.
    The "BDAT" construct is the only ACPI mechanism that relies on SeaBIOS
    reserved memory.  Replace it with the SSDT based template system.
    Signed-off-by: Kevin O'Connor <kevin at koconnor.net>

I'll look at it more tomorrow, I should already be asleep by now.  When
I boot a linux guest on qemu with a device behind a bridge I see "no
compatible bridge window for <range>" messages and the apertures get
de-programmed.  So I think the VGA patch here still works, but it's kind
of useless as only the VGA ranges get routed and we can't even get to
VESA modes because of the apertures getting shutdown.  Thanks,


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