LE(4) MidnightBSD Kernel Interfaces Manual LE(4)

NAME

le — AMD Am7900 LANCE and Am79C9xx 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"

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) chip set.

The le driver also supports PCnet adapters based on the AMD 79C9xx 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 chip sets supported by the pcn(4) driver. The le driver treats all of these PCI bus Ethernet chip sets 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 chip sets. Thus the pcn(4) driver should be preferred for the latter.

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

PCI
The PCI bus Ethernet chip sets 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

The le driver supports the following media types with these chip sets:

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 following media types are available with these:

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.

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

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〉.

MidnightBSD 0.3 January 30, 2006 MidnightBSD 0.3