Re: atyfb & lockups
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2005-12-02 02:21:08
Well, there are other possibilities. When does the lockup occure? Immediately when booting? Later? During start of xdm/kdm? Random?
During boot, when drawing text in console mode, usually when it starts scrolling but not necessarily.
I would start to investigate the case by instrumenting and extending the fb_sync code. Try to include code there that resets the chip and switches to the noaccel counterparts of the accelerated functions when a timeout occures. That way you should have a chance to resume.
Yah, I should do something like that. I remember trying to track that bug down a while ago now, and I think I had it working by adding syncs all over the place. However, I think the problem is more likely to be some bad fifo or bandwidth setting in the engine causing it to lockup when loaded. It works if I boot MacOS and use BootX to then boot linux, though I then have different display problems (definitely look like incorrect settings of the display fifo).
Is the timeout counter ok? Maybe you should decrease/increase it. If switching to the noaccel function works, include a register dump before resetting the chip, use show_trace() etc for further debugging.
Will do all of these as soon as I find some time. My initial post was mostly to ping in case it was a known issue or somebody else already tracked it down. Ben. ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click