.\" $NetBSD: gem.4,v 1.2 2003/02/14 15:20:18 grant Exp $
.\"
.\" Copyright (c) 2002 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.\" $FreeBSD: releng/12.2/share/man/man4/gem.4 267938 2014-06-26 21:46:14Z bapt $
.\"
.Dd December 25, 2009
.Dt GEM 4
.Os
.Sh NAME
.Nm gem
.Nd ERI/GEM/GMAC Ethernet device driver
.Sh SYNOPSIS
To compile this driver into the kernel,
place the following lines in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device miibus"
.Cd "device gem"
.Ed
.Pp
Alternatively, to load the driver as a
module at boot time, place the following line in
.Xr loader.conf 5 :
.Bd -literal -offset indent
if_gem_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver provides support for the GMAC Ethernet hardware found mostly in
the last Apple PowerBooks G3s and most G4-based Apple hardware, as
well as Sun UltraSPARC machines.
.Pp
All controllers supported by the
.Nm
driver have TCP checksum offload capability for both receive and transmit,
support for the reception and transmission of extended frames for
.Xr vlan 4
and a 512-bit multicast hash filter.
.Sh HARDWARE
Chips supported by the
.Nm
driver include:
.Pp
.Bl -bullet -compact
.It
Apple GMAC
.It
Sun ERI 10/100 Mbps Ethernet
.It
Sun GEM Gigabit Ethernet
.El
.Pp
The
following add-on cards are known to work with the
.Nm
driver at this time:
.Pp
.Bl -bullet -compact
.It
Sun Gigabit Ethernet PCI 2.0/3.0 (GBE/P)
(part no.\& 501-4373)
.It
Sun Gigabit Ethernet SBus 2.0/3.0 (GBE/S)
(part no.\& 501-4375)
.El
.Sh NOTES
On sparc64 the
.Nm
driver respects the
.Va local-mac-address?
system configuration variable which can be set in the Open Firmware boot
monitor using the
.Ic setenv
command or by
.Xr eeprom 8 .
If set to
.Dq Li false
(the default), the
.Nm
driver will use the system's default MAC address for all of its devices.
If set to
.Dq Li true ,
the unique MAC address of each interface is used if present rather than
the system's default MAC address.
.Pp
Supported interfaces having their own MAC address include the on-board
Sun ERI 10/100 Mbps on boards equipped with more than one Ethernet interface
and the Sun Gigabit Ethernet 2.0/3.0 GBE add-on cards.
.Sh SEE ALSO
.Xr altq 4 ,
.Xr miibus 4 ,
.Xr netintro 4 ,
.Xr vlan 4 ,
.Xr eeprom 8 ,
.Xr ifconfig 8
.Sh HISTORY
The
.Nm
device driver appeared in
.Nx 1.6 .
The first
.Fx
version to include it was
.Fx 5.0 .
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was written for
.Nx
by
.An Eduardo Horvath Aq Mt eeh@NetBSD.org .
It was ported to
.Fx
by
.An Thomas Moestl Aq Mt tmm@FreeBSD.org
and later on improved by
.An Marius Strobl Aq Mt marius@FreeBSD.org .
The man page was written by
.An Thomas Klausner Aq Mt wiz@NetBSD.org .