[Intel-gfx] [PATCH] drm/i915: Delay seqno reads on Haswell !rcs engines

[Chris Wilson]

On Tue, Apr 26, 2016 at 04:24:17PM +0100, Chris Wilson wrote:
> Haswell is showing missed interrupt syndrome again. The inference is
> that we are reading the seqno too early (i.e. before the write has been
> posted by the GPU). Increase the delay for Haswell by invalidating the
> cacheline and forcing the seqno read from memory.

Just after I sent this, my Crystalwell flagged a missed interrupt (on
bcs).
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre