[Intel-gfx] [PATCH v2 2/2] drm/i915/guc: handle GuC messages received with CTB disabled

[Chris Wilson]

Quoting Daniele Ceraolo Spurio (2019-06-21 19:21:23)
> There is a very small chance of triggering a log flush event when
> enabling or disabling CT buffers. Events triggered while CT buffers
> are disabled are logged in the SCRATCH_15 register using the same bits
> used in the CT message payload. Since our communication channel with
> GuC is turned off, we can save the message and handle it after we turn
> it back on.
> GuC should be idle and not generate more events in the meantime because
> we're not talking to it.
> 
> v2: clear the mmio register on stop_communication as well (Chris)
> 
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>

I'll take your word that the guc leaves useful tidbits of info there.
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris