Re: [Qemu-devel] How to get 1280x1024 display from guest running Xorg?

[Robin Atwood]

On Wednesday 21 Feb 2007, Ben Taylor wrote:
> ---- Robin Atwood <address@hidden> wrote:
> > This has been driving me mad! I have just installed Solaris 10 under Qemu
> > and specified the Xorg server to be used. I created xorg.conf with
> > xorgconfig and X started fine at 1024x768 using the Cirrus driver. When I
> > edited xorg.conf to specify a 1280x1024 display, the Xorg.0.log file
> > showed "no mode".
>
> You may have to define HorizSync and VertRefresh in the xorg.conf file.
>
> I have a nexenta alpha 6 with updates that just comes up in 1280x800 by
> setting the HorizSync value in the xorg.conf.
>
> > Now, I
> > have both Win XP and Plan 9 running at 1280x1024, so I booted up XP and
> > poked around the "Display/Settings" dialog and determined XP was running
> > the display at 1280x1024 at 43Hz interlaced and 16 bit colour.
>
> So you also need to define DefaultDepth in the xorg.conf file.
>
> > So, using the
> > handy http://xtiming.sourceforge.net site, I generated a mode line like
> > XP's and added it to the xorg.conf file. X refused the interlaced mode so
> > I tried an uninterlaced one at 43Hz. That kind of worked but only
> > rendered half the screen! Everything else I tried got rejected as "bad
> > mode..."
>
> Since the virtual monitor doesn't specify EDID, it is unlikely to be able
> to handle resolutions over the basic ones.  I know that a while ago (maybe
> 18 months) I was able to get something like 1156x864 out of the adapter
> with early versions of Solaris express.
> .
>
> > So does someone have a magic modeline or xorg.conf to get Xorg going in a
> > guest at high-res? There's another guy on the Linux-under-Qemu forum with
> > the same problem hosting Ubuntu. I am using qemu 0.9, FWIW.
>
> Probably a combination of HorizSync/VertRefresh in the monitor section,
> DefaultDepth in the Screen section, and a mode line, you might get what
> you want.

Solved it, and it was so simple! There is a qemu CLI option "-std-vga" which 
causes an enhanced Bochs VGA adaptor to be emulated. So, specify that when 
you boot, use the VESA driver in xorg.conf and the default 1280x1024 mode now 
works.

From the man page:
-std-vga
 Simulate a standard VGA card with Bochs VBE extensions (default is Cirrus 
Logic GD5446 PCI VGA). If your guest OS supports the VESA 2.0 VBE extensions 
(e.g. Windows XP) and if you want to use high resolution modes (>= 
1280x1024x16) then you should use this option. 

I think this is a recent update because I recall looking at this option and 
deciding it was not what I needed. Or, I am going blind...

Cheers...
-Robin.
-- 
----------------------------------------------------------------------
Robin Atwood.

"Ship me somewheres east of Suez, where the best is like the worst,
 Where there ain't no Ten Commandments an' a man can raise a thirst"
         from "Mandalay" by Rudyard Kipling
----------------------------------------------------------------------