if (ixFeatureCtrlDeviceRead() == IX_FEATURE_CTRL_DEVICE_TYPE_IXP42X) {
                                switch (ixFeatureCtrlProductIdRead() & IX_FEATURE_CTRL_SILICON_STEPPING_MASK) {
                                case IX_FEATURE_CTRL_SILICON_TYPE_B0:
+                               default: /* newer than B0 */
                                        /*
-                                        * If it is B0 Silicon, we only enable port when its corresponding
-                                        * Eth Coprocessor is available.
+                                        * If it is B0 or newer Silicon, we
+                                        * only enable port when its
+                                        * corresponding Eth Coprocessor is
+                                        * available.
                                         */
                                        if (ixFeatureCtrlComponentCheck(IX_FEATURECTRL_ETH0) ==
                                            IX_FEATURE_CTRL_COMPONENT_ENABLED)