AHCI(4)                   OpenBSD Programmer's Manual                  AHCI(4)

NAME
     ahci - Advanced Host Controller Interface for Serial ATA

SYNOPSIS
     ahci* at pci?
     ahci* at jmb?
     scsibus* at ahci?

DESCRIPTION
     The ahci driver provides support for Serial ATA controllers conforming to
     the Advanced Host Controller Interface specification.

     Several AHCI capable controllers also provide a compatibility mode that
     causes them to appear as a traditional ATA controller supported by
     pciide(4).

     Although ahci controllers are actual ATA controllers, the driver emulates
     SCSI via a translation layer.

     Setting the lowest bit (0x1) of the driver flags forces ahci to negotiate
     SATA 1 (1.5 Gb/s) transfer speeds only.  It may be useful where higher
     speeds are unstable.

SEE ALSO
     intro(4), jmb(4), pci(4), pciide(4), scsi(4)

HISTORY
     The ahci driver first appeared in OpenBSD 4.1.

AUTHORS
     The ahci driver was written by David Gwynne <dlg@openbsd.org> and
     Christopher Pascoe <pascoe@openbsd.org>.

OpenBSD 4.7                    December 12, 2009                             1
