NAME

     le — AMD Am7900 LANCE and Am79C9xx ILACC/PCnet Ethernet interface driver

SYNOPSIS

     To compile this driver into the kernel, place the following line in your kernel configuration file:

           device le

     Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

           if_le_load="YES"

     For ISA non-PnP adapters, the port address as well as the IRQ and the DRQ numbers have to be specified in
     /boot/device.hints:
     hint.le.0.at="isa"
     hint.le.0.port="0x280"
     hint.le.0.irq="10"
     hint.le.0.drq="0"

DESCRIPTION

     The le driver provides support for Ethernet adapters based on the AMD Am7990 and Am79C90 (CMOS,
     pin-compatible) Local Area Network Controller for Ethernet (LANCE) chips.

     The le driver also supports Ethernet adapters based on the AMD Am79C900 Integrated Local Area
     Communications Controller (ILACC) as well as the Am79C9xx PCnet family of chips, which are single-chip
     implementations of a LANCE chip and a DMA engine.  This includes a superset of the PCI bus Ethernet chips
     supported by the pcn(4) driver.  The le driver treats all of these PCI bus Ethernet chips as an AMD
     Am79C970 PCnet-PCI and does not support the additional features like the MII bus and burst mode of AMD
     Am79C971 PCnet-FAST and greater chips.  Thus the pcn(4) driver should be preferred for the latter.

     Generally, the le driver aims at supporting as many different chips on as many different platforms as
     possible, partially at the cost of the best performance with some of these.

     The le driver supports reception and transmission of extended frames for vlan(4).  Selective reception of
     multicast Ethernet frames is provided by a 64-bit mask; multicast destination addresses are hashed to a bit
     entry using the Ethernet CRC function.

HARDWARE

   ISA
     The le driver supports ISA bus Ethernet adapters which are based on the following chips:

     •   AMD Am7990 and Am79C90 LANCE
     •   AMD Am79C960 PCnet-ISA
     •   AMD Am79C961 PCnet-ISA+
     •   AMD Am79C961A PCnet-ISA II

     This includes support for the following Ethernet adapters:

     ISA non-PnP:

     •   BICC Isolan
     •   Novell NE2100

     ISA PnP:

     •   AMD AM1500T/AM2100
     •   AMD PCnet-32
     •   AMD PCnet-ISA
     •   Allied Telesyn AT-1500
     •   Boca LANCard Combo
     •   Cabletron E2100 Series DNI
     •   Cabletron E2200 Single Chip
     •   Melco Inc. LGY-IV
     •   Novell NE2100
     •   Racal InterLan EtherBlaster

     The le driver does not support the selection of media types and options via ifconfig(8) with ISA bus
     Ethernet adapters.

   PCI
     The PCI bus Ethernet chips supported by the le driver are:

     •   AMD Am53C974/Am79C970/Am79C974 PCnet-PCI
     •   AMD Am79C970A PCnet-PCI II
     •   AMD Am79C971 PCnet-FAST
     •   AMD Am79C972 PCnet-FAST+
     •   AMD Am79C973/Am79C975 PCnet-FAST III
     •   AMD Am79C976 PCnet-PRO
     •   AMD Am79C978 PCnet-Home

     This includes support for the following Ethernet adapters:

     •   AcerLAN NIC P20
     •   Allied Telesyn AT-2450 and AT-2700 series
     •   VMware emulated AMD Am79C970A PCnet-PCI II interface

     The le driver supports the selection of the following media types via ifconfig(8) with PCI bus Ethernet
     adapters:

     autoselect   Enable autoselection of the media type.

     10baseT/UTP  Select UTP media.

     10base5/AUI  Select AUI/BNC media.

     The following media option is supported with these media types:

     full-duplex  Select full duplex operation.

     Note that unlike the pcn(4) driver, the le driver does not support selecting 100Mbps (Fast Ethernet) media
     types.

   sparc64
     The le driver supports the on-board LANCE interfaces found in Sun Ultra 1 machines.  The le driver allows
     the selection of the following media types via ifconfig(8) with these on-board interfaces:

     autoselect   Enable autoselection of the media type.

     10baseT/UTP  Select UTP media.

     10base5/AUI  Select AUI media.

     When using autoselection, a default media type is selected for use by examining all ports for carrier.  The
     first media type with which a carrier is detected will be selected.  Additionally, if carrier is dropped on
     a port, the driver will switch between the possible ports until one with carrier is found.

     The le driver also supports the following Sun SBus Ethernet add-on adapters:

     •   SCSI HBA and Buffered Ethernet (SBE/S, P/N 501-1869)
     •   Fast SCSI and Buffered Ethernet (FSBE/S, P/N 501-2015 and 501-2981)

     The le driver does not support the selection of media types and options via ifconfig(8) with SBus Ethernet
     add-on adapters.

     For further information on configuring media types and options, see ifconfig(8).

DIAGNOSTICS

     le%d: overflow  More packets came in from the Ethernet than there was space in the LANCE receive buffers.
     Packets were missed.

     le%d: receive buffer error  The LANCE ran out of buffer space, packet dropped.

     le%d: lost carrier  The Ethernet carrier disappeared during an attempt to transmit.  The LANCE will finish
     transmitting the current packet, but will not automatically retry transmission if there is a collision.

     le%d: excessive collisions, tdr %d  The Ethernet was extremely busy or jammed, outbound packets were
     dropped after 16 attempts to retransmit.

     TDR is the abbreviation of "Time Domain Reflectometry".  The optionally reported TDR value is an internal
     counter of the interval between the start of a transmission and the occurrence of a collision.  This value
     can be used to determine the distance from the Ethernet tap to the point on the Ethernet cable that is
     shorted or open (unterminated).

     le%d: dropping chained buffer  A packet did not fit into a single receive buffer and was dropped.  Since
     the le driver allocates buffers large enough to receive maximum sized Ethernet packets, this means some
     other station on the LAN transmitted a packet larger than allowed by the Ethernet standard.

     le%d: transmit buffer error  The LANCE ran out of buffer space before finishing the transmission of a
     packet.  If this error occurs, the driver software has a bug.

     le%d: underflow  The LANCE ran out of buffer space before finishing the transmission of a packet.  If this
     error occurs, the driver software has a bug.

     le%d: controller failed to initialize  Driver failed to start the LANCE.  This is potentially a hardware
     failure.

     le%d: memory error  RAM failed to respond within the timeout when the LANCE wanted to read or write it.
     This is potentially a hardware failure.

     le%d: receiver disabled  The receiver of the LANCE was turned off due to an error.

     le%d: transmitter disabled  The transmitter of the LANCE was turned off due to an error.

SEE ALSO

     altq(4), arp(4), intro(4), netintro(4), pcn(4), vlan(4), ifconfig(8)

HISTORY

     The le driver was ported from NetBSD and first appeared in FreeBSD 6.1.  The NetBSD version in turn was
     derived from the le driver which first appeared in 4.4BSD.

AUTHORS

     The le driver was ported by Marius Strobl <marius@FreeBSD.org>.