ahci.4: Fix typo.
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1.\" $OpenBSD: ahci.4,v 1.7 2008/04/19 01:18:39 djm Exp $
2.\"
3.\" Copyright (c) 2006 David Gwynne <dlg@openbsd.org>
4.\"
5.\" Permission to use, copy, modify, and distribute this software for any
6.\" purpose with or without fee is hereby granted, provided that the above
7.\" copyright notice and this permission notice appear in all copies.
8.\"
9.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14.\" TORTIOUS ACTION, ARISING OUT OF
15.\" PERFORMANCE OF THIS SOFTWARE.
16.\"
17.Dd June 15, 2009
18.Dt AHCI 4
19.Os
20.Sh NAME
21.Nm ahci
22.Nd Advanced Host Controller Interface for Serial ATA
23.Sh SYNOPSIS
24To compile this driver into the kernel,
25place the following line in your
26kernel configuration file:
27.Bd -ragged -offset indent
28.Cd "device ahci"
29.Ed
30.Pp
31Alternatively, to load the driver as a
32module at boot time, place the following line in
33.Xr loader.conf 5 :
34.Bd -literal -offset indent
35ahci_load="YES"
36.Ed
37.Sh DESCRIPTION
38The
39.Nm
40driver provides support for Serial ATA controllers conforming to the
41Advanced Host Controller Interface specification.
42.Pp
5a205d6e 43Several AHCI capable controllers also provide a compatibility mode that
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44causes them to appear as a traditional ATA controller supported by
45.Xr nata 4 .
46.Pp
47Although
48.Nm
49controllers are actual ATA controllers, the driver emulates SCSI via a
50translation layer.
51.Pp
52Setting the lowest bit (0x1) of the driver flags forces
53.Nm
54to negotiate SATA 1 (1.5 Gb/s) transfer speeds only.
55It may be useful where higher speeds are unstable.
56.Sh SEE ALSO
57.Xr intro 4 ,
58.Xr pci 4 ,
59.Xr nata 4 ,
60.Xr scsi 4 ,
61.Xr loader.conf 5
62.Sh HISTORY
63The
64.Nm
65driver first appeared in
66.Dx 2.3 .
67.Sh AUTHORS
68.An -nosplit
69The
70.Nm
71driver was originally written by
72.An David Gwynne Aq dlg@openbsd.org
73and
74.An Christopher Pascoe Aq pascoe@openbsd.org
75for
76.Ox .
77.Pp
78It was ported to
79.Dx
80by
81.An Matt Dillon Aq dillon@apollo.backplane.com
82who added new features such as port multiplier support.