Tearing on VGA output, LVDS OK on 950GMA with xf86-video-intel-2.6.10

kokoko3k · 2010-03-06 12:35:56

I'm crossposting this message i sent on intel-graphics ml and xorg bugzilla, because maybe some of you can point me to a solution.

i own an asus eeepc1005ha, it uses intel gma 950.
Playing a video on the internal LVDS panel is very pleasing and tear
free, but as soon as i connect the vga output, i can notice tearing or
flickering on the picture.
I tried all possible configurations:
-Booting with the lid open (tty on LVDS) and then switching to xorg
with a VGA only output. (VGA tears)
-Booting with the lid closed (tty on VGA) and using xorg on VGA. (VGA tears)
-VGA+LVDS in clone mode (VGA and LVDS tears)
-VGA+LVDS in multihead mode (expanded desktop) (VGA and LVDS tears)

Using xv adaptor via mplayer results in a different tear effect, seems
more like a flickering, while the GL output definitely tears.

I couldn't try overlay adaptor because i don't have a 2.6.33 kernel yet
(believe it or not, i've seen overlay tearing too with an old intel
driver in the past, i think 2.7.1, in a cloned mode if lvds was at
60hz, while vga was at 70hz)

I'm using xf86-video-intel 2.10.0 and kernel 2.6.32.9

I used the framerate test videos available here:
http://spng.se/frame-rate-test/

Thanks for reading.

Last edited by kokoko3k (2010-03-07 08:23:48)

steve___ · 2010-03-07 16:13:31

When cross posting I suggest including the urls to the other posts.

I have two machine with intel cards in them. I haven't used the computers for a while now but when I was I noticed video tearing. To solve the problem I used this command:

mplayer -vo xv:port="$(xvinfo |grep -A 2 "Adaptor #0" |grep base |sed s'/port base: //')"

I haven't tested the command with the newer drivers nor the newer kernels. I hope this helps you.

kokoko3k · 2010-03-07 16:47:13

You're right, here's the references:
http://lists.freedesktop.org/archives/i … 06092.html
http://bugs.freedesktop.org/show_bug.cgi?id=26925

About your command, i'll try, but what it does is just picking the first port from first adaptor, right?
By now (xf86-video-intel 2.10.0 and kernel 2.6.32.9), we just have a single adaptor, the textured one;
why the first port should make a difference?
Maybe with your setup the overlay adaptor was picked, and in 99% of the cases that would certanly help.
As a side note, newer mplayer versions comes with an useful option: -vo xv:adaptor=#

What i think is that vblank interrupts generation is (and was) messed up in the drivers code.
see:

(believe it or not, i've seen overlay tearing too with an old intel
driver in the past, i think 2.7.1, in a cloned mode if lvds was at
60hz, while vga was at 70hz)

steve___ · 2010-03-07 17:14:43

kokoko3k wrote:

why the first port should make a difference?
Maybe with your setup the overlay adaptor was picked, and in 99% of the cases that would certanly help.
As a side note, newer mplayer versions comes with an useful option: -vo xv:adaptor=#

My first port was the xv overlay adaptor. That command was part of a function in my $HOME/.bashrc file, as the port was different on my two machines.

What i think is that vblank interrupts generation is (and was) messed up in the drivers code.
see:
(believe it or not, i've seen overlay tearing too with an old intel
driver in the past, i think 2.7.1, in a cloned mode if lvds was at
60hz, while vga was at 70hz)

Yeah, seeing as I haven't used those machines in a while, I wasn't sure the command I supplied was relevant... thus I was hoping it would help you. Once I noticed the video tearing it was all I could see :-/

Arch Linux

#1 2010-03-06 12:35:56

Tearing on VGA output, LVDS OK on 950GMA with xf86-video-intel-2.6.10

#2 2010-03-07 16:13:31

Re: Tearing on VGA output, LVDS OK on 950GMA with xf86-video-intel-2.6.10

#3 2010-03-07 16:47:13

Re: Tearing on VGA output, LVDS OK on 950GMA with xf86-video-intel-2.6.10

#4 2010-03-07 17:14:43

Re: Tearing on VGA output, LVDS OK on 950GMA with xf86-video-intel-2.6.10

Board footer