xref: /freebsd/share/man/man4/le.4 (revision e71d18f4108f0f00bcc017c3674c77df010a187c)
135591247SMarius Strobl.\"	$NetBSD: le.4,v 1.22 2004/10/04 19:12:52 rumble Exp $
235591247SMarius Strobl.\"
335591247SMarius Strobl.\"-
435591247SMarius Strobl.\" Copyright (c) 1992, 1993
535591247SMarius Strobl.\"	The Regents of the University of California.  All rights reserved.
635591247SMarius Strobl.\"
735591247SMarius Strobl.\" This software was developed by the Computer Systems Engineering group
835591247SMarius Strobl.\" at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
935591247SMarius Strobl.\" contributed to Berkeley.
1035591247SMarius Strobl.\"
1135591247SMarius Strobl.\" Redistribution and use in source and binary forms, with or without
1235591247SMarius Strobl.\" modification, are permitted provided that the following conditions
1335591247SMarius Strobl.\" are met:
1435591247SMarius Strobl.\" 1. Redistributions of source code must retain the above copyright
1535591247SMarius Strobl.\"    notice, this list of conditions and the following disclaimer.
1635591247SMarius Strobl.\" 2. Redistributions in binary form must reproduce the above copyright
1735591247SMarius Strobl.\"    notice, this list of conditions and the following disclaimer in the
1835591247SMarius Strobl.\"    documentation and/or other materials provided with the distribution.
1935591247SMarius Strobl.\" 3. Neither the name of the University nor the names of its contributors
2035591247SMarius Strobl.\"    may be used to endorse or promote products derived from this software
2135591247SMarius Strobl.\"    without specific prior written permission.
2235591247SMarius Strobl.\"
2335591247SMarius Strobl.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
2435591247SMarius Strobl.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2535591247SMarius Strobl.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2635591247SMarius Strobl.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
2735591247SMarius Strobl.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2835591247SMarius Strobl.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2935591247SMarius Strobl.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
3035591247SMarius Strobl.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
3135591247SMarius Strobl.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
3235591247SMarius Strobl.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
3335591247SMarius Strobl.\" SUCH DAMAGE.
3435591247SMarius Strobl.\"
3535591247SMarius Strobl.\"	from: Header: le.4,v 1.2 92/10/13 05:31:33 leres Exp
3635591247SMarius Strobl.\"	from: @(#)le.4	8.1 (Berkeley) 6/9/93
3735591247SMarius Strobl.\" $FreeBSD$
3835591247SMarius Strobl.\"
39e71d18f4SMarius Strobl.Dd November 9, 2006
4035591247SMarius Strobl.Dt LE 4
4135591247SMarius Strobl.Os
4235591247SMarius Strobl.Sh NAME
4335591247SMarius Strobl.Nm le
4435591247SMarius Strobl.Nd "AMD Am7900 LANCE and Am79C9xx PCnet Ethernet interface driver"
4535591247SMarius Strobl.Sh SYNOPSIS
4635591247SMarius StroblTo compile this driver into the kernel,
4735591247SMarius Stroblplace the following line in your
4835591247SMarius Stroblkernel configuration file:
4935591247SMarius Strobl.Bd -ragged -offset indent
5035591247SMarius Strobl.Cd "device le"
5135591247SMarius Strobl.Ed
5235591247SMarius Strobl.Pp
5335591247SMarius StroblAlternatively, to load the driver as a
5435591247SMarius Stroblmodule at boot time, place the following line in
5535591247SMarius Strobl.Xr loader.conf 5 :
5635591247SMarius Strobl.Bd -literal -offset indent
5735591247SMarius Stroblif_le_load="YES"
5835591247SMarius Strobl.Ed
590ab9d31cSMarius Strobl.Pp
600ab9d31cSMarius StroblFor C-Bus non-PnP cards, the port address and the IRQ number have to be
610ab9d31cSMarius Stroblspecified in
620ab9d31cSMarius Strobl.Pa /boot/device.hints :
630ab9d31cSMarius Strobl.Cd hint.le.0.at="isa"
640ab9d31cSMarius Strobl.Cd hint.le.0.port="0x03d0"
650ab9d31cSMarius Strobl.Cd hint.le.0.irq="6"
660ab9d31cSMarius Strobl.Pp
670ab9d31cSMarius StroblFor ISA non-PnP cards, the port address as well as the IRQ and the DRQ
680ab9d31cSMarius Stroblnumbers have to be specified in
690ab9d31cSMarius Strobl.Pa /boot/device.hints :
700ab9d31cSMarius Strobl.Cd hint.le.0.at="isa"
710ab9d31cSMarius Strobl.Cd hint.le.0.port="0x280"
720ab9d31cSMarius Strobl.Cd hint.le.0.irq="10"
730ab9d31cSMarius Strobl.Cd hint.le.0.drq="0"
7435591247SMarius Strobl.Sh DESCRIPTION
7535591247SMarius StroblThe
7635591247SMarius Strobl.Nm
7735591247SMarius Strobldriver provides support for Ethernet adapters based on the
7835591247SMarius Strobl.Tn AMD
7935591247SMarius StroblAm7990 and Am79C90 (CMOS, pin-compatible)
8035591247SMarius StroblLocal Area Network Controller for Ethernet
8135591247SMarius Strobl.Pq Tn LANCE
820ab9d31cSMarius Stroblchips.
8335591247SMarius Strobl.Pp
8435591247SMarius StroblThe
8535591247SMarius Strobl.Nm
860ab9d31cSMarius Strobldriver also supports Ethernet adapters based on the
8735591247SMarius Strobl.Tn AMD 79C9xx
8835591247SMarius Stroblfamily of chips, which are single-chip implementations of a
8935591247SMarius Strobl.Tn LANCE
90e9646f64SMarius Stroblchip and a DMA engine.
91e9646f64SMarius StroblThis includes a superset of the
9235591247SMarius Strobl.Tn PCI
930ab9d31cSMarius Stroblbus Ethernet chips supported by the
9435591247SMarius Strobl.Xr pcn 4
9535591247SMarius Strobldriver.
9635591247SMarius StroblThe
9735591247SMarius Strobl.Nm
98e9646f64SMarius Strobldriver treats all of these
99e9646f64SMarius Strobl.Tn PCI
1000ab9d31cSMarius Stroblbus Ethernet chips as an
101e9646f64SMarius Strobl.Tn AMD Am79C970 PCnet-PCI
102e9646f64SMarius Strobland does not support the additional features like the MII bus and burst mode of
103e9646f64SMarius Strobl.Tn AMD Am79C971 PCnet-FAST
1040ab9d31cSMarius Strobland greater chips.
105e9646f64SMarius StroblThus the
10635591247SMarius Strobl.Xr pcn 4
107e9646f64SMarius Strobldriver should be preferred for the latter.
10835591247SMarius Strobl.Pp
1090ab9d31cSMarius StroblGenerally, the
1100ab9d31cSMarius Strobl.Nm
1110ab9d31cSMarius Strobldriver aims at supporting as many different chips on as many different
1120ab9d31cSMarius Stroblplatforms as possible,
1130ab9d31cSMarius Stroblpartially at the cost of the best performance with some of these.
1140ab9d31cSMarius Strobl.Pp
11535591247SMarius StroblThe
11635591247SMarius Strobl.Nm
11735591247SMarius Strobldriver supports reception and transmission of extended frames for
11835591247SMarius Strobl.Xr vlan 4 .
11935591247SMarius StroblSelective reception of multicast Ethernet frames is provided by a 64-bit mask;
12035591247SMarius Stroblmulticast destination addresses are hashed to a bit entry using the Ethernet
12135591247SMarius StroblCRC function.
12235591247SMarius Strobl.Sh HARDWARE
1230ab9d31cSMarius Strobl.Ss C-Bus and ISA
1240ab9d31cSMarius StroblThe
1250ab9d31cSMarius Strobl.Nm
1260ab9d31cSMarius Strobldriver supports
1270ab9d31cSMarius Strobl.Tn C-Bus
1280ab9d31cSMarius Strobland
1290ab9d31cSMarius Strobl.Tn ISA
1300ab9d31cSMarius Stroblbus Ethernet adapters which are based on the following chips:
1310ab9d31cSMarius Strobl.Pp
1320ab9d31cSMarius Strobl.Bl -bullet -compact
1330ab9d31cSMarius Strobl.It
1340ab9d31cSMarius Strobl.Tn AMD Am7990 and Am79C90 LANCE
1350ab9d31cSMarius Strobl.It
1360ab9d31cSMarius Strobl.Tn AMD Am79C960 PCnet-ISA
1370ab9d31cSMarius Strobl.It
1380ab9d31cSMarius Strobl.Tn AMD Am79C961 PCnet-ISA+
1390ab9d31cSMarius Strobl.It
1400ab9d31cSMarius Strobl.Tn AMD Am79C961A PCnet-ISA II
1410ab9d31cSMarius Strobl.El
1420ab9d31cSMarius Strobl.Pp
1430ab9d31cSMarius StroblThis includes support for the following Ethernet adapters:
1440ab9d31cSMarius Strobl.Pp
1450ab9d31cSMarius StroblC-Bus non-PnP:
1460ab9d31cSMarius Strobl.Pp
1470ab9d31cSMarius Strobl.Bl -bullet -compact
1480ab9d31cSMarius Strobl.It
1490ab9d31cSMarius Strobl.Tn Contec C-NET(98)S
1500ab9d31cSMarius Strobl.El
1510ab9d31cSMarius Strobl.Pp
1520ab9d31cSMarius StroblISA non-PnP:
1530ab9d31cSMarius Strobl.Pp
1540ab9d31cSMarius Strobl.Bl -bullet -compact
1550ab9d31cSMarius Strobl.It
1560ab9d31cSMarius Strobl.Tn BICC Isolan
15735591247SMarius Strobl.\" .It
15835591247SMarius Strobl.\" .Tn Digital DEPCA
1590ab9d31cSMarius Strobl.It
1600ab9d31cSMarius Strobl.Tn Novell NE2100
1610ab9d31cSMarius Strobl.El
1620ab9d31cSMarius Strobl.Pp
1630ab9d31cSMarius StroblISA PnP:
1640ab9d31cSMarius Strobl.Pp
1650ab9d31cSMarius Strobl.Bl -bullet -compact
1660ab9d31cSMarius Strobl.It
1670ab9d31cSMarius Strobl.Tn AMD AM1500T/AM2100
1680ab9d31cSMarius Strobl.It
1690ab9d31cSMarius Strobl.Tn AMD PCnet-32
1700ab9d31cSMarius Strobl.It
1710ab9d31cSMarius Strobl.Tn AMD PCnet-ISA
1720ab9d31cSMarius Strobl.It
173e71d18f4SMarius Strobl.Tn Allied Telesyn AT-1500
174e71d18f4SMarius Strobl.It
1750ab9d31cSMarius Strobl.Tn Boca LANCard Combo
1760ab9d31cSMarius Strobl.It
1770ab9d31cSMarius Strobl.Tn Cabletron E2100 Series DNI
1780ab9d31cSMarius Strobl.It
1790ab9d31cSMarius Strobl.Tn Cabletron E2200 Single Chip
1800ab9d31cSMarius Strobl.It
1810ab9d31cSMarius Strobl.Tn Melco Inc. LGY-IV
1820ab9d31cSMarius Strobl.It
1830ab9d31cSMarius Strobl.Tn Novell NE2100
1840ab9d31cSMarius Strobl.It
1850ab9d31cSMarius Strobl.Tn Racal InterLan EtherBlaster
1860ab9d31cSMarius Strobl.El
1870ab9d31cSMarius Strobl.Pp
1880ab9d31cSMarius StroblThe
1890ab9d31cSMarius Strobl.Nm
1900ab9d31cSMarius Strobldriver does not support the selection of media types and options via
1910ab9d31cSMarius Strobl.Xr ifconfig 8
1920ab9d31cSMarius Stroblwith
1930ab9d31cSMarius Strobl.Tn C-Bus
1940ab9d31cSMarius Strobland
1950ab9d31cSMarius Strobl.Tn ISA
1960ab9d31cSMarius Stroblbus Ethernet adapters.
19735591247SMarius Strobl.\" .Ss EISA
19835591247SMarius Strobl.\" The
19935591247SMarius Strobl.\" .Tn EISA
20035591247SMarius Strobl.\" bus Ethernet cards supported by the
20135591247SMarius Strobl.\" .Nm
20235591247SMarius Strobl.\" driver are:
20335591247SMarius Strobl.\" .Pp
20435591247SMarius Strobl.\" .Bl -bullet -compact
20535591247SMarius Strobl.\" .It
20635591247SMarius Strobl.\" .Tn DEC DE422
20735591247SMarius Strobl.\" .El
20835591247SMarius Strobl.\" .Ss MCA
20935591247SMarius Strobl.\" The
21035591247SMarius Strobl.\" .Tn MCA
21135591247SMarius Strobl.\" bus Ethernet cards supported by the
21235591247SMarius Strobl.\" .Nm
21335591247SMarius Strobl.\" driver are:
21435591247SMarius Strobl.\" .Pp
21535591247SMarius Strobl.\" .Bl -bullet -compact
21635591247SMarius Strobl.\" .It
21735591247SMarius Strobl.\" .Tn SKNET Personal MC2
21835591247SMarius Strobl.\" .It
21935591247SMarius Strobl.\" .Tn SKNET MC2+
22035591247SMarius Strobl.\" .El
22135591247SMarius Strobl.Ss PCI
22235591247SMarius StroblThe
22335591247SMarius Strobl.Tn PCI
2240ab9d31cSMarius Stroblbus Ethernet chips supported by the
22535591247SMarius Strobl.Nm
22635591247SMarius Strobldriver are:
22735591247SMarius Strobl.Pp
22835591247SMarius Strobl.Bl -bullet -compact
22935591247SMarius Strobl.It
23035591247SMarius Strobl.Tn AMD Am53C974/Am79C970/Am79C974 PCnet-PCI
23135591247SMarius Strobl.It
23235591247SMarius Strobl.Tn AMD Am79C970A PCnet-PCI II
23335591247SMarius Strobl.It
23435591247SMarius Strobl.Tn AMD Am79C971 PCnet-FAST
23535591247SMarius Strobl.It
23635591247SMarius Strobl.Tn AMD Am79C972 PCnet-FAST+
23735591247SMarius Strobl.It
23835591247SMarius Strobl.Tn AMD Am79C973/Am79C975 PCnet-FAST III
23935591247SMarius Strobl.It
24035591247SMarius Strobl.Tn AMD Am79C976 PCnet-PRO
24135591247SMarius Strobl.It
24235591247SMarius Strobl.Tn AMD Am79C978 PCnet-Home
24335591247SMarius Strobl.El
24435591247SMarius Strobl.Pp
24535591247SMarius StroblThe
24635591247SMarius Strobl.Nm
2470ab9d31cSMarius Strobldriver supports the following media types with these chips:
248ae91966bSRuslan Ermilov.Bl -tag -width ".Cm 10base5/AUI"
249ae91966bSRuslan Ermilov.It Cm autoselect
25035591247SMarius StroblEnable autoselection of the media type.
251ae91966bSRuslan Ermilov.It Cm 10baseT/UTP
25235591247SMarius StroblSelect UTP media.
253ae91966bSRuslan Ermilov.It Cm 10base5/AUI
25435591247SMarius StroblSelect AUI/BNC media.
25535591247SMarius Strobl.El
25635591247SMarius Strobl.Pp
25735591247SMarius StroblThe following media option is supported with these media types:
258ae91966bSRuslan Ermilov.Bl -tag -width ".Cm full-duplex"
259ae91966bSRuslan Ermilov.It Cm full-duplex
26035591247SMarius StroblSelect full duplex operation.
26135591247SMarius Strobl.El
26235591247SMarius Strobl.Pp
26335591247SMarius StroblNote that unlike the
26435591247SMarius Strobl.Xr pcn 4
26535591247SMarius Strobldriver, the
26635591247SMarius Strobl.Nm
26735591247SMarius Strobldriver does not support selecting 100Mbps (Fast Ethernet) media types.
26835591247SMarius Strobl.Ss sparc64
26935591247SMarius StroblThe
27035591247SMarius Strobl.Nm
27135591247SMarius Strobldriver supports the on-board
27235591247SMarius Strobl.Tn LANCE
27335591247SMarius Stroblinterfaces found in
27435591247SMarius Strobl.Tn Sun Ultra 1
27535591247SMarius Stroblmachines.
27635591247SMarius StroblThe following media types are available with these:
277ae91966bSRuslan Ermilov.Bl -tag -width ".Cm 10base5/AUI"
278ae91966bSRuslan Ermilov.It Cm autoselect
27935591247SMarius StroblEnable autoselection of the media type.
280ae91966bSRuslan Ermilov.It Cm 10baseT/UTP
28135591247SMarius StroblSelect UTP media.
282ae91966bSRuslan Ermilov.It Cm 10base5/AUI
28335591247SMarius StroblSelect AUI media.
28435591247SMarius Strobl.El
28535591247SMarius Strobl.Pp
28635591247SMarius StroblWhen using autoselection, a default media type is selected for use by
28735591247SMarius Stroblexamining all ports for carrier.
28835591247SMarius StroblThe first media type with which a carrier is detected will be selected.
28935591247SMarius StroblAdditionally, if carrier is dropped on a port, the driver will switch
29035591247SMarius Stroblbetween the possible ports until one with carrier is found.
29135591247SMarius Strobl.\" .Pp
29235591247SMarius Strobl.\" The
29335591247SMarius Strobl.\" .Nm
29435591247SMarius Strobl.\" driver also supports
29535591247SMarius Strobl.\" .Tn SBus
29635591247SMarius Strobl.\" Ethernet cards.
29735591247SMarius Strobl.\" These include:
29835591247SMarius Strobl.\" .Bl -bullet -compact
29935591247SMarius Strobl.\" .It
30035591247SMarius Strobl.\" SBE/S
30135591247SMarius Strobl.\" .Tn SCSI
30235591247SMarius Strobl.\" and Buffered Ethernet
30335591247SMarius Strobl.\" (Sun P/N 501-1860)
30435591247SMarius Strobl.\" .It
30535591247SMarius Strobl.\" FSBE/S
30635591247SMarius Strobl.\" Fast
30735591247SMarius Strobl.\" .Tn SCSI
30835591247SMarius Strobl.\" and Buffered Ethernet
30935591247SMarius Strobl.\" (Sun P/N 501-2015)
31035591247SMarius Strobl.\" .El
31135591247SMarius Strobl.Pp
31235591247SMarius StroblFor further information on configuring media types and options, see
31335591247SMarius Strobl.Xr ifconfig 8 .
31435591247SMarius Strobl.Sh DIAGNOSTICS
31535591247SMarius Strobl.Bl -diag
31635591247SMarius Strobl.It "le%d: overflow"
31735591247SMarius StroblMore packets came in from the Ethernet than there was space in the
31835591247SMarius Strobl.Tn LANCE
31935591247SMarius Stroblreceive buffers.
32035591247SMarius StroblPackets were missed.
32135591247SMarius Strobl.It "le%d: receive buffer error"
32235591247SMarius StroblThe
32335591247SMarius Strobl.Tn LANCE
32435591247SMarius Stroblran out of buffer space, packet dropped.
32535591247SMarius Strobl.It "le%d: lost carrier"
32635591247SMarius StroblThe Ethernet carrier disappeared during an attempt to transmit.
32735591247SMarius StroblThe
32835591247SMarius Strobl.Tn LANCE
32935591247SMarius Stroblwill finish transmitting the current packet,
33035591247SMarius Stroblbut will not automatically retry transmission if there is a collision.
33135591247SMarius Strobl.It "le%d: excessive collisions, tdr %d"
33235591247SMarius StroblThe Ethernet was extremely busy or jammed,
33335591247SMarius Strobloutbound packets were dropped after 16 attempts to retransmit.
33435591247SMarius Strobl.Pp
33535591247SMarius StroblTDR
33635591247SMarius Stroblis the abbreviation of
33735591247SMarius Strobl.Qq Time Domain Reflectometry .
33835591247SMarius StroblThe optionally reported TDR value is an internal counter of the interval
33935591247SMarius Stroblbetween the start of a transmission and the occurrence of a collision.
34035591247SMarius StroblThis value can be used to determine the distance from the Ethernet tap to
34135591247SMarius Stroblthe point on the Ethernet cable that is shorted or open (unterminated).
34235591247SMarius Strobl.It "le%d: dropping chained buffer"
34335591247SMarius StroblA packet did not fit into a single receive buffer and was dropped.
34435591247SMarius StroblSince the
34535591247SMarius Strobl.Nm
34635591247SMarius Strobldriver allocates buffers large enough to receive maximum sized Ethernet
34735591247SMarius Stroblpackets, this means some other station on the LAN transmitted a packet
34835591247SMarius Strobllarger than allowed by the Ethernet standard.
34935591247SMarius Strobl.It "le%d: transmit buffer error"
35035591247SMarius StroblThe
35135591247SMarius Strobl.Tn LANCE
35235591247SMarius Stroblran out of buffer space before finishing the transmission of a packet.
35335591247SMarius StroblIf this error occurs, the driver software has a bug.
35435591247SMarius Strobl.It "le%d: underflow"
35535591247SMarius StroblThe
35635591247SMarius Strobl.Tn LANCE
35735591247SMarius Stroblran out of buffer space before finishing the transmission of a packet.
35835591247SMarius StroblIf this error occurs, the driver software has a bug.
35935591247SMarius Strobl.It "le%d: controller failed to initialize"
36035591247SMarius StroblDriver failed to start the
36135591247SMarius Strobl.Tn LANCE .
36235591247SMarius StroblThis is potentially a hardware failure.
36335591247SMarius Strobl.It "le%d: memory error"
36435591247SMarius StroblRAM failed to respond within the timeout when the
36535591247SMarius Strobl.Tn LANCE
36635591247SMarius Stroblwanted to read or write it.
36735591247SMarius StroblThis is potentially a hardware failure.
36835591247SMarius Strobl.It "le%d: receiver disabled"
36935591247SMarius StroblThe receiver of the
37035591247SMarius Strobl.Tn LANCE
37135591247SMarius Stroblwas turned off due to an error.
37235591247SMarius Strobl.It "le%d: transmitter disabled"
37335591247SMarius StroblThe transmitter of the
37435591247SMarius Strobl.Tn LANCE
37535591247SMarius Stroblwas turned off due to an error.
37635591247SMarius Strobl.El
37735591247SMarius Strobl.Sh SEE ALSO
37835591247SMarius Strobl.Xr arp 4 ,
37935591247SMarius Strobl.Xr intro 4 ,
38035591247SMarius Strobl.Xr netintro 4 ,
38135591247SMarius Strobl.Xr pcn 4 ,
38235591247SMarius Strobl.Xr vlan 4 ,
38335591247SMarius Strobl.Xr ifconfig 8
38435591247SMarius Strobl.Sh HISTORY
38535591247SMarius StroblThe
38635591247SMarius Strobl.Nm
38735591247SMarius Strobldriver was ported from
38835591247SMarius Strobl.Nx
38935591247SMarius Strobland first appeared in
39035591247SMarius Strobl.Fx 6.1 .
39135591247SMarius StroblThe
39235591247SMarius Strobl.Nx
39335591247SMarius Stroblversion in turn was derived from the
39435591247SMarius Strobl.Nm
39535591247SMarius Strobldriver which first appeared in
39635591247SMarius Strobl.Bx 4.4 .
39735591247SMarius Strobl.Sh AUTHORS
39835591247SMarius StroblThe
39935591247SMarius Strobl.Nm
40035591247SMarius Strobldriver was ported by
40135591247SMarius Strobl.An "Marius Strobl" Aq marius@FreeBSD.org .
40235591247SMarius Strobl.\" .Sh BUGS
40335591247SMarius Strobl.\" The Am7990 Revision C chips have a bug which causes garbage to be inserted
40435591247SMarius Strobl.\" in front of the received packet occasionally.
40535591247SMarius Strobl.\" The work-around is to ignore packets with an invalid destination address
40635591247SMarius Strobl.\" (garbage will usually not match), by double-checking the destination
40735591247SMarius Strobl.\" address of every packet in the driver.
40835591247SMarius Strobl.\" This work-around can be enabled with the
40935591247SMarius Strobl.\" .Dv LANCE_REVC_BUG
41035591247SMarius Strobl.\" kernel option.
41135591247SMarius Strobl.\" .Pp
41235591247SMarius Strobl.\" When
41335591247SMarius Strobl.\" .Dv LANCE_REVC_BUG
41435591247SMarius Strobl.\" is enabled, the
41535591247SMarius Strobl.\" .Nm
41635591247SMarius Strobl.\" driver executes one or two calls to an inline Ethernet address comparison
41735591247SMarius Strobl.\" function for every received packet.
41835591247SMarius Strobl.\" On the
41935591247SMarius Strobl.\" .Tn MC68000
42035591247SMarius Strobl.\" it is exactly eight instructions of 16 bits each.
42135591247SMarius Strobl.\" There is one comparison for each unicast packet, and two comparisons for
42235591247SMarius Strobl.\" each broadcast packet.
42335591247SMarius Strobl.\" .Pp
42435591247SMarius Strobl.\" In summary, the cost of the LANCE_REVC_BUG option is:
42535591247SMarius Strobl.\" .Bl -enum -compact
42635591247SMarius Strobl.\" .It
42735591247SMarius Strobl.\" loss of multicast support, and
42835591247SMarius Strobl.\" .It
42935591247SMarius Strobl.\" eight extra
43035591247SMarius Strobl.\" .Tn CPU
43135591247SMarius Strobl.\" instructions per received packet, sometimes sixteen, depending on both the
43235591247SMarius Strobl.\" processor, and the type of packet.
43335591247SMarius Strobl.\" .El
43435591247SMarius Strobl.\" .Pp
43535591247SMarius Strobl.\" All sun3 systems are presumed to have this bad revision of the Am7990,
43635591247SMarius Strobl.\" until proven otherwise.
43735591247SMarius Strobl.\" Alas, the only way to prove what revision of the chip is in a particular
43835591247SMarius Strobl.\" system is inspection of the date code on the chip package,
43935591247SMarius Strobl.\" to compare against a list of what chip revisions were fabricated between
44035591247SMarius Strobl.\" which dates.
44135591247SMarius Strobl.\" .Pp
44235591247SMarius Strobl.\" Alas, the Am7990 chip is so old that
44335591247SMarius Strobl.\" .Tn AMD
44435591247SMarius Strobl.\" has
44535591247SMarius Strobl.\" .Qq de-archived
44635591247SMarius Strobl.\" the production information about it; pending a search elsewhere, we do not
44735591247SMarius Strobl.\" know how to identify the revision C chip from the date codes.
448