Chris Wilson writes:
> Be paranoid and make sure we flush any and all writes out of the WCB
> before performing the UC mmio to update the RING_TAIL. (An UC write
> should itself be enough to do the flush, hence the paranoia here.) Quite
> infrequently, we see problems where the GPU seems to
Be paranoid and make sure we flush any and all writes out of the WCB
before performing the UC mmio to update the RING_TAIL. (An UC write
should itself be enough to do the flush, hence the paranoia here.) Quite
infrequently, we see problems where the GPU seems to overshoot the
RING_TAIL and so
