.\" $FreeBSD$
.\" Written by Tom Rhodes
.\" This file is in the public domain.
.\"
.Dd December 29, 2002
.Dt CISS 4
.Os
.Sh NAME
.Nm ciss
.Nd Common Interface for SCSI-3 Support driver.
.Sh SYNOPSIS
For one or more adapters:
.Cd device scbus
.Cd device ciss
.Sh DESCRIPTION
.Pp
The
.Nm
driver claims to provide a common interface between generic SCSI
transports and intelligent host adapters.
.Pp
The
.Nm
driver supports
.Em CISS
as defined in the document entitled
.Dq CISS Command Interface for SCSI-3 Support Open Specification ,
Version 1.04,
Valence Number 1, dated 20001127, produced by Compaq Computer
Corporation.
.Pp
We provide a shim layer between the
.Nm
interface and CAM,
offloading most of the queueing and being-a-disk chores onto CAM.
Entry to the driver is via the PCI bus attachment
.Fa ciss_probe ,
.Fa ciss_attach ,
etc and via the CAM interface
.Fa ciss_cam_action ,
and
.Fa ciss_cam_poll .
The Compaq
.Nm
adapters require faked responses to get reasonable
behavior out of them.
In addition, the
.Nm
command set is by no means adequate to support the functionality of a RAID controller,
and thus the supported Compaq adapters utilize portions of the
control protocol from earlier Compaq adapter families.
.Pp
Currently
.Nm
only supports the
.Dq simple
transport layer over PCI.
This interface (ab)uses the I2O register set (specifically the post
queues) to exchange commands with the adapter.
Other interfaces are available, but we are not supposed to know about them,
and it is dubious whether they would provide major performance improvements
except under extreme load.
.Sh COMPATIBILITY
Non disk devices (such as internal DATs and devices
attached to the external SCSI bus) are not yet supported.
.Pp
Supported controllers include:
.Pp
.Bl -tag -compact -width "Compaq Smart Array 5* series"
.It Compaq Smart Array 5300
.It Compaq Smart Array 532
.It Compaq Smart Array 5i
.El
.Sh SEE ALSO
.Xr cam 4 ,
.Xr pass 4 ,
.Xr xpt 4 ,
.Xr camcontrol 8 ,
.Pp
.Dq CISS Command Interface for SCSI-3 Support Open Specification, Version 1.04,
Valence Number 1, dated 20001127, produced by Compaq Computer Corporation.
.Sh AUTHORS
The
.Nm
driver was written by
.An Mike Smith Aq msmith@FreeBSD.org .
This manual page is based on his comments and was written by
.An Tom Rhodes Aq trhodes@FreeBSD.org .