drm/i915/icl: Forcibly evict stale csb entries
Gen11 fails to deliver wrt global observation point on tail/entry updates and we sometimes see old entry. Use clflush to forcibly evict our possibly stale copy of the cacheline in hopes that we get fresh one from gpu. Obviously there is something amiss in the coherency protocol so this can be consired as a workaround until real cause is found. The working hardware will do the evict without our cue anyways, so the cost in there should be ameliorated by that fact. v2: for next pass, s/flush/evict, add reset (Chris) References: https://bugzilla.freedesktop.org/show_bug.cgi?id=108315 Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by:Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by:
Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20181205134612.24822-1-mika.kuoppala@linux.intel.com
parent
490b8c65
Please register or sign in to comment