CAC_EISA_CHANNEL_CLEAR
CAC_EISA_CHANNEL_CLEAR) == 0);
cac_outb(sc, CAC_EISAREG_SYSTEM_DOORBELL, CAC_EISA_CHANNEL_CLEAR);
cac_outb(sc, CAC_EISAREG_LOCAL_DOORBELL, CAC_EISA_CHANNEL_CLEAR);
~CAC_EISA_CHANNEL_CLEAR);