Comment 13 for bug 541511

Created an attachment (id=34353)
new patch with totally reworked chipset flush

I've combined a few of my previous, non-working ideas and combined them into this new patch. Hopefully this adapts better to different cpu/chipset combinations (i.e. better chance that it not only works on my machine). The new chipset flush is a magic dance involving a flock of canaries ;)

The magic values (look at include/drm/intel-gtt.h, but not at the comments, their stale) probably need some tuning. But this new chipset flush is adaptive (fyi it reports the maximum number of retries in the regular chipset flush no. reporting), so I hope it works out of the box.

Unfortunately I haven't yet fixed the BUG_ON in put_pages. For some odd reason I can't reproduce it here anymore and reviewing the code hasn't revealed anything yet.

As usual, testing reports highly welcome.