AT_HCYL
ata_ctlp->ac_hcyl = (uchar_t *)ioaddr1 + AT_HCYL;
if (ddi_get8(io_hdl, (uchar_t *)ioaddr + AT_HCYL) == ATAPI_SIG_HI &&
ddi_put8(io_hdl, (uchar_t *)ioaddr + AT_HCYL, 0);