On Wed, Jul 17, 2013 at 3:18 AM, Selim T. Erdogan <
se...@alumni.cs.utexas.edu> wrote:
> Joel Rees, 16.07.2013:
> > On Mon, Jul 15, 2013 at 4:52 PM, Joel Rees <joel.r...@gmail.com> wrote:
> >
> > > On Mon, Jul 15, 2013 at 6:36 AM, Mike Kupfer <m.kup...@acm.org> wrote:
> > >
> > >> Joel Rees wrote:
> > >>
> > >> > > Anybody else seen this? Have an idea what's going on?
> > >>
> > >> I haven't seen this, nor do I know what's going on, but here are some
> > >> things I would check if I were seeing that sort of video breakage:
> > >>
> > >
> > > Thanks for responding. I was wondering if everyone had kill-filed me.
> > >
> > >
> > >> Do you have compositing enabled (under Window Manager Tweaks)? If you
> > >> do, does the problem go away if you disable compositing?
> > >>
> > >
> > > Compositing is not enabled, according to the GUI. Maybe I should try
> > > enabling it. (My son's monopolizing the box right now.)
> > >
> >
> > Hmm. I enabled compositing and, while the blit leftovers don't
> immediately
> > go away, sometimes, but not always, several seconds after they appear,
> they
> > go away.
> >
> >
> > > I'm assuming that you're using more or less standard Xfce.
> > >
> > >
> > > Haven't been ambitious enough to do a lot of modding, so it should be.
> But
> > > I'm not confident I got all the implicit dependencies taken care of
> when I
> > > upgraded from squeeze to wheezy.
> > >
> > >
> > >> If that's
> > >> incorrect, a more detailed description of your desktop setup would be
> > >> helpful.
> > >>
> > >> And do you know what video card you're using and what driver?
> > >>
> > >
> > > On-board graphics on a cheap AMD (Sempron) motherboard -- VIA
> KM266pro, I
> > > think, maybe KM400, + VT8237 -- from about eight or nine years ago.
> > >
> >
> > >From "lspci -nn | grep VGA" :
> >
> > 01:00.0 VGA compatible controller [0300]: VIA Technologies, Inc.
> > KM400/KN400/P4M800 [S3 UniChrome] [1106:7205] (rev 01)
>
> I actually have the same card (in an Averatec 3200 series laptop from
> 2004, with an AMD Athlon processor) and I might have a solution for you.
> For several months now, I've had some minor problems where I suspected
> the video driver was the issue and finally this weekend I dove into the
> code to check things out. So your timing is good. :)
>
Great!
> The "leftover stuff" problem isn't actually one that I'm having directly
> but it is similar to something I've seen. For a long time, when I
> turned the computer on after hibernating, sometimes my graphics would be
> messed up and I would have to log out and back in to fix it. I haven't
> had it happen very much recently but I'm not sure it was fixed directly
> because it seems related to my next problem...
>
> I use gnome-3 in fallback mode and the icons at the top right ---
> battery, sound, network --- wouldn' get updated to reflect the
> current state, though the hovering-clicking functions worked correctly.
> They would only get refreshed when I went to a virtual terminal with
> ctrl-alt-f1 and came back with alt-f7.
>
Yeah, the delayed refresh aspect does sound similar.
> This weekend I figured out that this not-refreshing is due to the driver
> switching its default to Exa, from Xaa. When I put
>
> Option "AccelMethod" "Xaa"
>
> in the Device section of my xorg.conf, the icons are refreshed
> properly.
And I have no xor.cong. Running pure default. Last time I generated an
xorg.conf, I decided I didn't want to do that any more. But I guess it has
to be. So I just ran
Xorg :1 -configure
and it tells me that the number of created screens does not match the
number of detected devices. Heh. But it gave me an xorg.conf.new in the
/root directory with enough device lines to try mucking with it. Lots of
stuff to mess with if I had time, various buffer sizes, BIOS settings
(although, with only 3/4G of system RAM, trying to tune the buffer sizes
could turn into a great thumb-twiddling exercise.
Setting "DisableIRQ" to "False" doesn't change things, at any rate.
Forgetting the quotes makes X11 not want to work, but the trusty old startx
works well enough to keep me in business testing without rebooting.
And ... setting "AccelMethod" to "Xaa" as you suggest ...
... does seem to cure the hesitation and the trash on the screen leftover
from botched blits.
This will definitely make it easier to use git and svn.
> Maybe this could fix your problem too. (This is just a
> workaround at the moment but I'm going to look into this some more.)
>
> The other problem I've noticed was that colors were cockeyed --- like
> the blue and the red were flipped or something --- when I played videos
> in vlc. I now have a patch that fixes this.
>
> Playing videos in totem also has problems, which I thought I'd noticed
> around the time I noticed it in vlc, but checking it again, it's a
> different problem --- videos show as a single garbled image --- and I
> haven't investigated that yet.
>
> I will be filing bugs for the exa-not-refreshing and flipped-colors
> issues this week but I wanted to test things one last time. I'll let
> the list know when I file the bugs.
>
> > I guess this is the appropriate comment on the state of the driver:
> >
> > http://packages.debian.org/wheezy/xserver-xorg-video-openchrome
> > --- hardware acceleration has been ripped out of the sourceforge code.
> >
> > Which sounds like some NPE went after the project.
>
> I looked up NPE and got Non-Practicing Entity. Is that what you
> meant? That wasn't what happened for this driver, as far as I know.
> In fact, at the url you gave above:
> ---
> Support for hardware acceleration (XvMC) for all chipsets has
> subsequently been ripped out of the unichrome.sf.net driver. Therefore
> your only option if you wish to make use of the acceleration features of
> your VIA chip with free and open-source drivers is to use this version
> of the driver.
> ---
> Meaning XvMC acceleration support is in the openchrome driver in debian.
>
> Here's the story: there was/is a driver called unichrome for these via
> cards that had both video acceleration and 3d.
> (The debian package description even has a URL for it:
> http://unichrome.sourceforge.net/) But the main developer of unichrome
> thought the code quality of the people working on the XvMC stuff was not
> good enough and there were disagreements. Eventually, he ripped
> that stuff out and openchrome was forked.
>
> (I've used unichrome in the past but I haven't tried it out in a
> couple of years. It doesn't get developed anymore, as far as I know,
> but I ran across a message on its list recently from somebody saying he
> managed to install it. I think its 3d support was better than
> openchrome's at the times when they first forked but they might
> have caught up. I don't know.)
>
> The bugs we're experiencing are probably due to there not being too much
> development activity around the openchrome driver and also regressions
> affecting older cards going unnoticed since there aren't too many users
> anymore.
>
> Selim
>
Thanks for the background on the unichrome versus openchrome projects.
--
Joel Rees
