EN_INTR_RET      2351 dev/ic/midway.c     EN_INTR_RET(0); /* not us */
EN_INTR_RET      2373 dev/ic/midway.c     EN_INTR_RET(1); /* for us */
EN_INTR_RET      2600 dev/ic/midway.c   EN_INTR_RET(1); /* for us */