drm/i915: Reset context image on engines after triggering the reset

We try to fixup the context image after the reset to ensure that there
are no more pending writes from the hw that may conflict and to fixup
any that were in flight.

Fixes: a1ef70e1 ("drm/i915: Add support for per engine reset recovery")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170721123238.16428-2-chris@chris-wilson.co.ukSigned-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.c

@@ -1950,6 +1950,8 @@ int i915_reset_engine(struct intel_engine_cs *engine)
 		goto out;
 	}
 
+	ret = intel_gpu_reset(engine->i915, intel_engine_flag(engine));
+
 	/*
 	 * The request that caused the hang is stuck on elsp, we know the
 	 * active request and can drop it, adjust head to skip the offending
@@ -1957,9 +1959,6 @@ int i915_reset_engine(struct intel_engine_cs *engine)
 	 */
 	i915_gem_reset_engine(engine, active_request);
 
-	/* Finally, reset just this engine. */
-	ret = intel_gpu_reset(engine->i915, intel_engine_flag(engine));
-
 	i915_gem_reset_finish_engine(engine);
 
 	if (ret) {