Re: [Qemu-devel] SPARC64: unable to boot OpenBIOS from git master

["Michael S. Tsirkin" <mst@redhat.com>]

On Sat, Mar 03, 2012 at 03:09:16PM +0000, Blue Swirl wrote:
> On Mon, Feb 27, 2012 at 06:36, Mark Cave-Ayland
> <mark.cave-ayland@ilande.co.uk> wrote:
> > Hi all,
> >
> > I've been experimenting with SPARC64 under QEMU, and with current git master
> > I am unable to boot OpenBIOS at all with the following error:
> >
> > OpenBIOS for Sparc64
> > Unhandled Exception 0x0000000000000032
> > PC = 0x00000000ffd19d84 NPC = 0x00000000ffd19d88
> > Stopping execution
> >
> > Using git bisect indicates that the problem lies with the following commit:
> >
> >
> > commit d5f27e88699f14c802d66c01de70e5ea37b7153a
> > Author: Michael S. Tsirkin <mst@redhat.com>
> > Date:   Tue Feb 21 15:57:58 2012 +0200
> >
> >    pci: set memory type for memory behind the bridge
> >
> >    As we make upper bits in IO and prefetcheable memory
> >    registers writeable, we should declare support
> >    for 64 bit prefetcheable memory and 32 bit io
> >    in the bridge.
> >
> >    This changes the default for apb, dec, but I'm guessing
> >    they got the defaults wrong by accident.
> >    Alternatively, we could let bridges declare lack of
> >    64 bit support and make the upper bits read-only zero.
> >
> >    With this applied, we can drop these bits
> >    from express code.
> >
> >    Reported-by: Gerd Hoffmann <kraxel@redhat.com>
> >    Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> >
> >    Could someone familiar with apb,dec ack this please?
> >    Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
> >
> >
> > Does anyone have an idea as to whether this is something that needs to be
> > fixed in QEMU or OpenBIOS?
> 
> No idea. Michael, should the commit be reverted?
> 
> It's easy to confirm the bug, just run qemu-system-sparc64 without any
> arguments. Bug: black screen, no bug: yellow screen with OpenBIOS boot
> text.
> 
> In fact, it's pretty annoying to see that even this very minimal
> amount of testing effort has not been spent by a critical subsystem
> maintainer.

My bad, I just sent out a fix.

> >
> > Many thanks,
> >
> > Mark.
> >