Using latest git xf96-video-intel I experience some buffer underruns on Pipe B together with a jittering of the image on the attached LVDS.
As Jesse told me I changed the critical value for DSPARB_BSTART_SHIFT from 64 to 48 and upto now it feels good. :)
OK, it is not yet totally gone, but not that frequent as before.
On my Mac mini Core Duo with i945, I also have a blank display after some time. In this case, I need to reboot to get the display back.
I'm still talking with the chipset guys about this; hopefully we'll have a resolution soon.
Out of curiosity, what does xrandr report on your machines? Can you attach your X log with "modedebug" enabled?
*** Bug 16536 has been marked as a duplicate of this bug. ***
Created attachment 17574 [details] [review]
split dsparb appropriately
Can you guys give this patch a try? Rather than statically allocating FIFO entries, it tries to choose a good split based on the programmed modes. Hopefully this will fix things for people without introducing any regressions.
Johannes and/or Jonathan, can you give the attached patch a try? It's one of the final blockers for the 2.4 release, I want to make sure it works. If it doesn't, I've still got another idea we can try.
Created attachment 17690 [details]
I am sorry, Jesse, but your patch makes the whole thing even worse, since the display does not even come up.
Created attachment 17729 [details] [review]
fix dsparb split
Oops, had an off by one in there. This one fixes that and includes 845/865 support too. Please try again!
That one seems to work perfectly. Thanks a lot! :)
Committed a slight variation on the patch. Thanks to everyone for testing on this one!
In what branch was the commit? And what was the commit hash? The only relevant commit I see is in master, but that one (b37a2a8ca82279468e3806dcf77d5fa7bdd0e874) only talks about 855 chips.
It is commit b8ca1c747a679c931267363639fc0bc690cae2d6.