xf86-video-intel: XV using the wrong pipe

[Alan Hourihane]

On Fri, 2007-04-13 at 22:31 +0800, JM Ibanez wrote:
> Alan Hourihane <alanh at fairlite.demon.co.uk> writes:
> 
> > On Fri, 2007-04-13 at 22:02 +0800, JM Ibanez wrote:
> >> Hi,
> >> 
> >> Since bugs.freedesktop.org seems to be down, I might as well report this
> >> here. Has anyone encountered this?
> >> 
> >> On my laptop, XVideo using xf86-video-intel git seems to be using the
> >> wrong pipe (or at least, it is "hardcoded" to just one pipe). When I
> >> have another display plugged in but cloned to the laptop's display
> >> (i.e. they're displaying the same image at the same resolution), running
> >> 'mplayer -vo xv /some/mpg/file' will show output on the external display
> >> and a blue screen on the laptop display. However, when I configure
> >> dual-head (mergefb), there's output when mplayer's window is in the
> >> external display, but blue screen on the local display.
> >> 
> >> Anyone experience this aside from me?
> >
> > That's actually a feature of the chip. It can't display the overlay to
> > both pipes at the same time. 
> >
> > If you run cloned on the same pipe, then it works, but there's the
> > restriction that the same resolution & refresh rate must be compatible
> > with both output devices.
> 
> It's the *same* resolution and *same* refresh rate.
> 
> And, it gets even more interesting.
> 
> Without any external display plugged in, nothing comes out when playing
> movies on the local display; *however*, when the external display is
> plugged in and is made a clone, output shows on the external display.
> 
> It's a bug, I tell you. :)

I bet you've got the option "Clone" in your xorg.conf ??

If so, it's not a bug, it's the feature I describe. You need to do
this..

Option "MonitorLayout" "NONE,CRT+LFP"

to get true cloned on a single pipe. And make sure you remove the Clone
option.

> To illustrate in crude ASCII graphics
> 
> - on clone:
>  +------------------+  +------------------+
>  |                  |  |                  |
>  |  external/VGA    |  |   laptop/LVDS    |
>  |                  |  |                  |
>  +------------------+  +------------------+
>    displays here          blue screen here

As mentioned above. It's probably the feature, not a bug.

> - on mergefb:
>  +------------------+  +------------------+
>  |                  |  |                  |
>  |  external/VGA    |  |   laptop/LVDS    |
>  |                  |  |                  |
>  +------------------+  +------------------+
>  overlay window here,
>  displays here
>
> 
>  +------------------+  +------------------+
>  |                  |  |                  |
>  |  external/VGA    |  |   laptop/LVDS    |
>  |                  |  |                  |
>  +------------------+  +------------------+
>                        overlay window here,
>                        blue screen

That may well be a bug, it should be flipping the output pipe for Xv
when the video window moves.

> > The alternative is to use textured overlay which will work either way.
> 
> How do you enable that on the i855GM? (considering also that I have DRI
> disabled due to my virtual screen size being larger than 2048)

You need to use the latest 1.9.94 driver.

Alan.