Re: [Qemu-devel] [Qemu-ppc] [PATCH 2/2] spapr: Add support for -vga option

[Matthew Garrett <mjg59@srcf.ucam.org>]

Dave Airlie wrote the dirty handling code, so Cc:ing him. I suspect 
transitioning offb over to a similar design would be fine by him.

On Mon, Jul 23, 2012 at 04:40:21PM +1000, Benjamin Herrenschmidt wrote:
> On Wed, 2012-06-27 at 17:25 -0500, Anthony Liguori wrote:
> 
> > If a user asks for something and we can't make it work, we should fail.
> 
> Note that QEMU's cirrus works fine with the new kernel cirrusdrmfb, so
> I say we should allow it (needs to be able to the powerpc device .mak
> as well tho.
> 
> It shouldn't be primary because old RHEL's iirc used to have cirrusfb
> enabled and that would blow due to guest kernel bugs among others.
> 
> I haven't had a chance to try whatever userspace DDX the Xorg folks have
> come up with to use on top of cirrusdrmfb, so that might need a bit of
> fixing but there's no reason not to allow -vga cirrus at this point.
> 
> Note to Matthew: cirrusdrmfb is a LOT SLOWER than offb for a similar
> SW only dumb framebuffer, probably has to do with the way it does the
> "dirty" stuff, not sure ...
> 
> Why not draw directly into the emulated vram ?
> 
> Cheers,
> Ben.
> 
> 
> 
-- 
Matthew Garrett | mjg59@srcf.ucam.org