ATA_IREASON
ch->r_io[ATA_IREASON].res = ch->r_io[ATA_COUNT].res;
ch->r_io[ATA_IREASON].offset = ch->r_io[ATA_COUNT].offset;
switch ((ATA_IDX_INB(ch, ATA_IREASON) & (ATA_I_CMD | ATA_I_IN)) |
int reason = ATA_IDX_INB(ch, ATA_IREASON);
int reason = ATA_INB(ch->r_mem, ATA_IREASON);
ireason = ATA_INB(ch->r_mem,ATA_IREASON);