drm/i915: Do a full device reset after being wedged

We only call unset_wedged on the global reset path (since it's a global
operation), so if we are terminally wedged and wish to reset, take the
full device reset path rather than the quicker individual engine resets.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180903083337.13134-1-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_irq.c

@@ -3309,7 +3309,8 @@ void i915_handle_error(struct drm_i915_private *dev_priv,
 	 * Try engine reset when available. We fall back to full reset if
 	 * single reset fails.
 	 */
-	if (intel_has_reset_engine(dev_priv)) {
+	if (intel_has_reset_engine(dev_priv) &&
+	    !i915_terminally_wedged(&dev_priv->gpu_error)) {
 		for_each_engine_masked(engine, dev_priv, engine_mask, tmp) {
 			BUILD_BUG_ON(I915_RESET_MODESET >= I915_RESET_ENGINE);
 			if (test_and_set_bit(I915_RESET_ENGINE + engine->id,