[Bug 2859] Flickering or blanking on DVI output of Radeon 9200/9250

[bugzilla-daemon at annarchy.freedesktop.org]

Please do not reply to this email: if you want to comment on the bug, go to    
       
the URL shown below and enter yourcomments there.     
   
https://bugs.freedesktop.org/show_bug.cgi?id=2859          
     




------- Additional Comments From sroland at tungstengraphics.com  2007-01-18 14:54 -------
(In reply to comment #74)
> > Basically, the tmds init values are "magic numbers" used to program the tmds
> > pll, it seems different values are optimal for different pixel clocks.
> 
> If this is by any means relevant, how come that I had no problem ever with any
> pixel clock values in XFree86 and older Xorg versions? And that I also have no
> problems at all now after building and loading the DRM module (which is a ~1
> minute task so I wonder why you didn't just do it).
Not all people here might suffer from the same issue actually, just the same
symptoms. One issue seems to be display buffer underflow, which I suspect is
what you got since enabling the dri/drm (and thus using cp accel instead of
mmio) changes timing/latency considerably. It would actually be possible to
detect such underflows so we'd know if that actually was the problem in a
specific case. Obviously, some people do not suffer from that (otherwise
changing the tmds_pll values wouldn't make any difference), and enabling dri
will not make any difference there (unless the driver has some really bad bug
and programs the tmds registers differently depending on that). I can't talk for
the others but I certainly had the drm module loaded (well I mentioned running
3d apps...), though not everyone can do that (not supported with all OS).
          
     
     
--           
Configure bugmail: https://bugs.freedesktop.org/userprefs.cgi?tab=email         
     
------- You are receiving this mail because: -------
You are on the CC list for the bug, or are watching someone who is.