On Thu, 05 Nov 2015, Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> wrote: > On Thu, Nov 05, 2015 at 01:11:38PM +0200, Mika Kuoppala wrote: >> We have a timed release of a forcewake when using >> I915_READ/WRITE macros. wait_for() macro will go to quite >> long sleep if the first read doesn't satisfy the condition for >> successful exit. With these two interacting, it is possible that >> we lose the forcewake during the wait_for() and the subsequent read >> will reaquire forcewake. >> >> Further experiments with skl shows that when we lose forcewake, >> we lose the reset request we submitted. So reset request register >> is not power context saved. >> >> Grab forcewakes for all engines before starting the reset/request >> dance so that all requests stay valid for the duration of reset >> requisition across all the engines. >> >> v2: Add comment on power well sleeps. Wrap the reset handling >> under forcewake instead of just reset requests (Chris) >> >> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92774 >> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> >> Tested-by: Tomi Sarvela <tomix.p.sarvela@xxxxxxxxx> (v1, v2) >> Signed-off-by: Mika Kuoppala <mika.kuoppala@xxxxxxxxx> > Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Pushed to drm-intel-next-fixes, thanks for the patch and review. BR, Jani. -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
