drm/i915/guc: Demote GuC error messages

We're using those functions in selftests, and the callers are expected
to do the error handling anyways. Let's demote all GuC actions and
doorbell creation to DEBUG_DRIVER.
Signed-off-by: NMichał Winiarski <michal.winiarski@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180319095348.9716-12-michal.winiarski@intel.com

drivers/gpu/drm/i915/intel_guc.c

@@ -362,9 +362,10 @@ int intel_guc_send_mmio(struct intel_guc *guc, const u32 *action, u32 len)
 		if (ret != -ETIMEDOUT)
 			ret = -EIO;
 
-		DRM_WARN("INTEL_GUC_SEND: Action 0x%X failed;"
-			 " ret=%d status=0x%08X response=0x%08X\n",
-			 action[0], ret, status, I915_READ(SOFT_SCRATCH(15)));
+		DRM_DEBUG_DRIVER("INTEL_GUC_SEND: Action 0x%X failed;"
+				 " ret=%d status=0x%08X response=0x%08X\n",
+				 action[0], ret, status,
+				 I915_READ(SOFT_SCRATCH(15)));
 	}
 
 	intel_uncore_forcewake_put(dev_priv, guc->send_regs.fw_domains);

drivers/gpu/drm/i915/intel_guc_submission.c

@@ -231,8 +231,8 @@ static int create_doorbell(struct intel_guc_client *client)
 	if (ret) {
 		__destroy_doorbell(client);
 		__update_doorbell_desc(client, GUC_DOORBELL_INVALID);
-		DRM_ERROR("Couldn't create client %u doorbell: %d\n",
-			  client->stage_id, ret);
+		DRM_DEBUG_DRIVER("Couldn't create client %u doorbell: %d\n",
+				 client->stage_id, ret);
 		return ret;
 	}