drm/nvf0/fifo: enable support

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/core/engine/device/nve0.c

@@ -163,8 +163,8 @@ nve0_identify(struct nouveau_device *device)
 		device->oclass[NVDEV_SUBDEV_VM     ] = &nvc0_vmmgr_oclass;
 		device->oclass[NVDEV_SUBDEV_BAR    ] = &nvc0_bar_oclass;
 		device->oclass[NVDEV_ENGINE_DMAOBJ ] = &nvd0_dmaeng_oclass;
-#if 0
 		device->oclass[NVDEV_ENGINE_FIFO   ] = &nve0_fifo_oclass;
+#if 0
 		device->oclass[NVDEV_ENGINE_SW     ] = &nvc0_software_oclass;
 		device->oclass[NVDEV_ENGINE_GR     ] =  nvf0_graph_oclass;
 #endif

drivers/gpu/drm/nouveau/core/engine/fifo/nve0.c

@@ -221,8 +221,10 @@ nve0_fifo_chan_ctor(struct nouveau_object *parent,
 		}
 	}
 
-	if (i == FIFO_ENGINE_NR)
+	if (i == FIFO_ENGINE_NR) {
+		nv_error(priv, "unsupported engines 0x%08x\n", args->engine);
 		return -ENODEV;
+	}
 
 	ret = nouveau_fifo_channel_create(parent, engine, oclass, 1,
 					  priv->user.bar.offset, 0x200,