xf86-video-intel: XV using the wrong pipe

[JM Ibanez]

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. :)

To illustrate in crude ASCII graphics

- on clone:
 +------------------+  +------------------+
 |                  |  |                  |
 |  external/VGA    |  |   laptop/LVDS    |
 |                  |  |                  |
 +------------------+  +------------------+
   displays here          blue screen here

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


 +------------------+  +------------------+
 |                  |  |                  |
 |  external/VGA    |  |   laptop/LVDS    |
 |                  |  |                  |
 +------------------+  +------------------+
                       overlay window here,
                       blue screen
>
> 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)

-- 
JM Ibanez
Software Architect
Orange & Bronze Software Labs, Ltd. Co.

jm at orangeandbronze.com
http://software.orangeandbronze.com/