AHCI_CAP_NCS_SHIFT
((ctlr->caps & AHCI_CAP_NCS) >> AHCI_CAP_NCS_SHIFT) + 1,
ch->numslots = ((ch->caps & AHCI_CAP_NCS) >> AHCI_CAP_NCS_SHIFT) + 1;
(slots << AHCI_CAP_NCS_SHIFT) | AHCI_CAP_SXS | (sc->ports - 1);