On Tue, Aug 13, 2013 at 10:29 PM, Daniel Vetter <daniel@xxxxxxxx> wrote: > On Tue, Aug 13, 2013 at 11:55:17AM -0700, Stéphane Marchesin wrote: >> It's basically the same deal as the RC6+ issues on ivy bridge >> except this time with RC6 on sandy bridge. Like last time the >> core of the issue is that the timings don't work 100% with our >> voltage regulator. So from time to time, the kernel will print >> a warning message about the GPU not getting out of RC6. In >> particular, I found this fairly easy to reproduce during >> suspend/resume. >> >> Changing the threshold to 125000 instead of 50000 seems to fix >> the issue. The previous patch used 150000 but as it turns out >> this doesn't work everywhere. After getting such a machine, I >> bisected the highest value which works, which is 125000, so here >> it is. >> >> I also measured the idle power usage before/after this patch and >> didn't see a difference on a sandy bridge laptop. On haswell and >> up, it makes a big difference, so we want to keep it at 50k >> there. It also seems like haswell doesn't have the RC6 issues >> that sandy bridge has so the 50k value is fine. >> >> Signed-off-by: Stéphane Marchesin <marcheu@xxxxxxxxxxxx> > Queued for -next, thanks for the patch. And it blew up: https://bugs.freedesktop.org/show_bug.cgi?id=71656 What do? We probably need a sysfs knob for this crap. Presuming no one has a brilliant idea I'll queue the revert next week. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
