1.\" $NetBSD: gem.4,v 1.10 2010/01/15 19:24:49 joerg Exp $ 2.\" 3.\" Copyright (c) 2002 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 16.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 17.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 18.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 19.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25.\" POSSIBILITY OF SUCH DAMAGE. 26.\" 27.Dd September 15, 2008 28.Dt GEM 4 29.Os 30.Sh NAME 31.Nm gem 32.Nd ERI/GEM/GMAC Ethernet device driver 33.Sh SYNOPSIS 34.Cd "gem* at pci? dev ? function ?" 35.Cd "gem* at sbus? slot ? offset ?" 36.Pp 37Configuration of PHYs may also be necessary. 38See 39.Xr mii 4 . 40.Sh DESCRIPTION 41The 42.Nm 43driver provides support for the GMac Ethernet hardware found mostly in 44the last Apple PowerBooks G3s and most G4-based Apple hardware, as 45well as many Sun UltraSPARCs. 46.Pp 47Cards supported by this driver include: 48.Bl -bullet -compact -offset indent 49.It 50Sun GEM gigabit ethernet (SX fibre variants) 51.It 52Sun ERI 10/100 53.It 54Apple GMAC 55.El 56.Pp 57The GEM family supports hardware checksumming to assist in computing 58IPv4 TCP checksums. 59The 60.Nm 61driver supports this feature of the chip. 62See 63.Xr ifconfig 8 64for information on how to enable this feature. 65.Sh SEE ALSO 66.Xr bmtphy 4 , 67.Xr ifmedia 4 , 68.Xr intro 4 , 69.Xr mii 4 , 70.Xr ifconfig 8 71.Rs 72.%T "GEM Gigabit Ethernet ASIC Specification" 73.%A Sun Microsystems 74.%U http://www.sun.com/processors/manuals/ge.pdf 75.Re 76.Rs 77.%T "Sbus GEM Specification" 78.%A Sun Microsystems 79.%U http://mediacast.sun.com/users/Barton808/media/gem_sbus-1.pdf 80.Re 81.Sh HISTORY 82The 83.Nm 84device driver appeared in 85.Nx 1.6 . 86Support for PCI SX fibre cards was added in 87.Nx 5.0 . 88Support for SBus SX fibre cards was added in 89.Nx 5.0 . 90.Sh AUTHORS 91.An -nosplit 92The 93.Nm 94driver was written by 95.An Eduardo Horvath 96.Aq eeh@NetBSD.org . 97SX fibre support was added by 98.An Julian Coleman 99.Aq jdc@NetBSD.org . 100The man page was written by 101.An Thomas Klausner 102.Aq wiz@NetBSD.org . 103.Sh BUGS 104The hardware checksumming support does not support IPv4 UDP, although this was 105allowed prior to 106.Nx 5.0 . 107Also, the hardware IPv4 TCP receive checksumming support has bugs, so this is 108disabled. 109.Pp 110On the SX fibre variants of the hardware, the link will stay down if there is 111a duplex mismatch. 112Also, packet transmission may fail when in 113.Cm half-duplex 114mode. 115