Re: Radeon jittery post 2.6.35

[Anders Eriksson <aeriksson@fastmail.fm>]

 On 03/18/11 09:55, Anders Eriksson wrote:
>  On 03/16/11 21:09, Anders Eriksson wrote:
> >  On 03/15/11 22:46, Alex Deucher wrote:
> > >  Try booting with radeon.audio=0 on 2.6.38rc, some TVs have problems
> > > with the hdmi packets we send by default.  disabling audio will treat
> > > the hdmi like dvi.
> > >
> > > Alex
> > You seem to be on to something there. radeon.audio=0 removes
> > what appears to be all of the jitter. I say "appear", because during
> > my many test runs today, I've come across moments where my brain
> > goes "wasn't what I just noticed on the TV something abnormal?" Both
> > in fb mode (post KMS), and in X11. It's definetly improved from useless
> > for family use, to perfectly ok though.
> >
> I was too early on this one. Yesterday (.38) , and today (38-rc8),
> are both jittery in post-KMS fb mode and in X, even though I use
> radeon.audio=0.
>
> A power cycling of the TV stabilizes it though.
>
> I'd be more than happy to test out any patches or ideas you might have.
>
> -A

It turns out all the failure patterns I've thought I've seen so far up
through .38.x are moot.

However, now on .39-rc, the KMS'd console is stable, and starting X
makes it bad again.

It there anything useful I can pull from any logs on the startup of X?
Either from the X
server, or the kernel. Last time I looked at the drm log from the kernel
It was unreadable
to a mere mortal, but I hope you guys can point me to what debug knobs
to enable to get a good
view of the interesting parts (How does one start a minimal X, btw?
"xinit" gives me an
undecorated xterm with the jitter. Can one start something more minimal?)

Currently running today's git xorg-server and xf86-video-dri.

-Anders