AHCI_P_FBS_EN
ATA_OUTL(ch->r_mem, AHCI_P_FBS, AHCI_P_FBS_EN | AHCI_P_FBS_DEC);
ATA_OUTL(ch->r_mem, AHCI_P_FBS, AHCI_P_FBS_EN |
ch->fbs_enabled ? AHCI_P_FBS_EN : 0);