If wrap just happened we need to prevent emitting waits for
pre wrap values. Detect this and emit no-ops instead.
v2: Use olr > seqno to detect wrap instead of *seqno == 0
as suggested by Chris Wilson.
v3: Use last used seqno to detect the wraparound. From
Chris Wilson
v4: Fixed unnecessary last_seqno assigment
References: https://bugs.freedesktop.org/show_bug.cgi?id=57967
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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