NAME

tlp — DECchip 21x4x and clone Ethernet interfaces device driver

SYNOPSIS

tlp* at eisa? slot ?
tlp* at pci? dev ? function ?
tlp* at cardbus? function ?

Configuration of PHYs may also be necessary. See mii(4).

DESCRIPTION

The tlp device driver supports Ethernet interfaces based on the DECchip 21x4x “Tulip” (DEC fourth generation Ethernet controller) and a variety of clone chips. The Tulip has several features designed to make it flexible and reduce CPU usage:

Flexible receive filter allowing for 16 perfect matches, 16 perfect inverse matches, 512-bit hash table plus 1 perfect match, or 512-bit hash table only.
Uniform transmit descriptor architecture, configurable as a ring (allowing 2 buffers per descriptor) or a chain (allowing 1 buffer per descriptor).
Uniform receive descriptor architecture, configurable as a ring (allowing 2 buffers per descriptor) or a chain (allowing 1 buffer per descriptor).
Interrupt pacing; host may choose whether or not completion of processing of an individual descriptor causes an interrupt.
Support for jumbo packets (by disabling transmit and receive watchdog timers).
A patented transmit backoff algorithm which solves the Ethernet capture effect problem.
Flexible bus modes to optimize DMA cycles for various cache sizes and bus implementations.
Programmable transmit FIFO drain threshold to allow DMA overlap and reduce time to transmit.
Flexible media attachment facilities.

The tlp driver supports the following chips:

DECchip 21040 -- This is the original Tulip Ethernet chip. It supports 10Mb/s speeds over a built-in serial interface. The serial interface has support for 10BASE-T and AUI media. The AUI port may be connected to 10BASE5 AUI or 10BASE2 BNC connectors, or both, selected by a gang jumper on the board. Some boards connect the BNC connector to an external serial interface. The driver has no way of knowing this, but the external serial interface may be selected with the “manual” media setting.
Boards that include this chip include the DEC DE-435, on-board Ethernet on many DEC AlphaStation and AlphaServer systems, ZNYX ZX312, ZX312T, ZX314, ZX315, SMC 8432, SMC 8434, ACCTON EN1203, and some Cogent multi-port boards.
This chip also appears on the DEC DE-425 EISA Ethernet board. This board is a DECchip 21040 and a PLX PCI glue chip, which provides the interface to the EISA bus, and special address decoding so that the PCI configuration space registers of the 21040 are accessible in normal EISA I/O space.
The very first versions of this chip were labeled “DC1003” and “DC1003 Prototype”.
DECchip 21041 -- This is the second chip in the Tulip family, dubbed “Tulip Plus”. It supports 10Mb/s speeds over a built-in serial interface. The serial interface has support for 10BASE-T, 10BASE5 AUI, and 10BASE2 BNC media. The serial interface also includes support for IEEE 802.3u NWay over the 10BASE-T interface, for negotiation of duplex mode with the link partner.
Boards that include this chip include the DEC DE-450 and some SMC boards.
DECchip 21140 and 21140A -- This is the third chip in the Tulip family, dubbed “FasterNet”. It supports 10Mb/s speeds with a built-in 10BASE-T encoder/decoder, and 100Mb/s speeds with a built-in 100BASE PCS function. Support for 100BASE-TX and 100BASE-T4 is provided by a built-in scrambler. Support for 100BASE-FX is possible with an appropriate PMD connected to the 100BASE PCS. The 21140 and 21140A also support 10Mb/s and 100Mb/s speeds over an MII interface connected to one or more PHYs.
The 21140 and 21140A include a general purpose I/O facility, which may be used to toggle relays on the board. This facility is often used to reset individual board modules (e.g. the MII bus), select the output path of the chip (e.g. connect the UTP port on the board to the PHY, built-in 10BASE-T ENDEC, or built-in 100BASE-T PMD), or detect link status (by reading an output pin on the 100BASE-T magnetics).
The 21140 and 21140A use a standardized data structure located in the SROM to describe how the chip should be programmed for various media settings, including the internal chip pathway, and GPIO settings. If the SROM data is not in the standardized format, the device driver must know specific programming information for that particular board.
Boards that include the 21140 and 21140A include the DEC EB140, DE-500XA, DE-500AA, Asante EtherFast, DaynaPORT BlueStreak, Cogent EM100TX, EM110TX, EM440T4 multi-port, Kingston KNE100TX, older versions of the NetGear FA-310TX, SMC 9332, SMC 9334, ZNYX ZX34x multi-port, and Adaptec ANA-6944A/TX multi-port.
DECchip 21142 and 21143 -- These are the fourth and fifth chips in the Tulip family. While they have two different chip numbers, the 21142 and 21143 are essentially identical, with only minor differences related to available technology at time of manufacture. Both chips include support for 10Mb/s speeds over a built-in serial interface, and support for 10Mb/s and 100Mb/s speeds over an MII interface connected to one or more PHYs. The serial interface includes support for 10BASE-T, 10BASE5 AUI, and 10BASE2 BNC media, as well as support for IEEE 802.3u NWay over the 10BASE-T interface, for negotiation of duplex mode and link speed with the link partner.
The 21143 adds support for 100Mb/s speeds with a built-in PCS function. Support for 100BASE-TX and 100BASE-T4 is provided by a built-in scrambler. Support for 100BASE-FX is possible with an appropriate PMD connected to the 100BASE PCS.
The 21142 and 21143 include a general purpose I/O facility, which may be used to toggle relays on the board. This facility is often used to reset individual board modules (e.g. the MII bus), select the output path of the chip (e.g. connect the UTP port on the board to the PHY, built-in serial interface, or built-in 100BASE-T PMD), or detect link status (by reading an output pin on the 100BASE-T magnetics).
The 21142 and 21143 use a standardized data structure located in the SROM to describe how the chip should be programmed for various media settings, including the internal chip pathway, and GPIO settings. If the SROM data is not in the standardized format, the device driver must know specific programming information for that particular board.
Boards that include the 21142 include the DEC EB142, and on-board Ethernet on the Digital Personal Workstation (Alpha “Miata” and x86 models) and several Digital PCs.
Boards that include the 21143 include the DEC EB143, DE-500BA, several commonly-available 100BASE-FX boards, the NetGear FA-510c CardBus card, and the Compu-Shack FASTline-II PCI boards.
Lite-On 82C168 and 82C169 -- These chips, dubbed “PNIC”, were some of the first commonly-available Tulip clones, appearing on low-cost boards when it became difficult for board vendors to obtain DECchip 21140A parts. They include support for 10Mb/s speeds over a built-in 10BASE-T encoder/decoder, and 100Mb/s speeds over a built-in PCS function. Support for 100BASE-TX and 100BASE-T4 is provided by a built-in scrambler and transceiver module. The transceiver module also includes support for NWay, for negotiating duplex mode and link speed with the link partner. These chips also include support for 10Mb/s and 100Mb/s speeds over and MII interface connected to one or more PHYs.
These chips also include a GPIO facility, although it is programmed differently than the 21140's.
Unfortunately, these chips seem to be plagued by two unfortunate hardware bugs: in some situations, the receive logic incorrectly dumps the entire transmit FIFO into the receive chain, rather than a single Ethernet frame, and the DMA engines appear to be substandard; they must be run in store-and-forward mode, and occasionally fail to upload the filter setup frame.
Boards that include the 82C168 and 82C169 include the newer NetGear FA-310TX, the Kingston KNE110TX, and some older LinkSys LNE100TX boards.
Macronix 98713, 98713A, 98715, 98715A, and 98725 -- Of all the clones, these chips, dubbed “PMAC”, are the best. They are very close clones of their respective originals, with the exception of some slight programming magic necessary to work around an apparent hardware bug.
The 98713 is a DECchip 21140A clone. It includes all of the 21140A's features, and uses the same SROM data format.
The 98713A is a half-clone of the DECchip 21143. It has support for serial, PCS, and MII media. The serial interface has a built-in NWay function. However, the 98713A does not have a GPIO facility, and, as a result, usually does not use the same SROM format as the 21143 (no need for GPIO programming information).
The 98715, 98715A, and 98725 are more 21143-like, but lack the GPIO facility and MII. These chips also support ACPI power management.
Boards that include the Macronix chips include some SVEC boards, some SOHOWare boards, and the Compex RL100TX.
Lite-On/Macronix 82C115 -- This chip, dubbed the “PNIC-II”, was co-designed by Lite-On and Macronix. It is almost identical to the Macronix 98725, with a few exceptions: it has Wake-On-LAN support, uses a 128-bit receive filter hash table, and supports IEEE 802.3x flow control.
Boards that include the 82C115 include the newer LinkSys (Version 2) LNE100TX boards.
Winbond 89C840F -- This chip is a very low-end barely-a-clone of the 21140. It supports 10Mb/s and 100Mb/s speeds over an MII interface only, and has several programming differences from the 21140.
The receive filter is completely different: it supports only a single perfect match, and has only a 64-bit multicast filter hash table. The receive filter is programmed using special registers rather than the standard Tulip setup frame.
This chip is also plagued by a terrible DMA engine. The chip must be run in store-and-forward mode or it will often transmit garbage onto the wire.
Interrupt pacing is also less flexible on the chip.
Boards that include the 89C940F include the Complex RL100ATX, some Unicom 10/100 boards, and several no-name 10/100 boards.
ADMtek AL981 -- This chip is a low cost, single-chip (sans magnetics) 10/100 Ethernet implementation. It supports 10Mb/s and 100Mb/s speeds over an internal PHY. There is no generic MII bus; instead the IEEE 802.3u-compliant PHY is accessed via special registers on the chip. This chip also supports Wake-On-LAN and IEEE 802.3x flow control.
The receive filter on the AL981 is completely different: it supports only a single perfect match, and has only a 64-bit multicast filter hash table. The receive filter is programmed using special registers rather than the standard Tulip setup frame.
This chip also supports ACPI power management.
A list of boards which include the AL981 is not yet available.
Support for the AL981 has not yet been tested. If you have a board which uses this chip, please contact the author (listed below).
Xircom X3201-3 -- This chip is a CardBus 21143 clone with a loosely-coupled modem function (the modem is on a separate CardBus function, but the MAC portion includes a shadow of its interrupt status). Media is provided by an IEEE 802.3u-compliant PHY connected to an MII interface. These chips have no SROM; instead, the MAC address must be obtained from the card's CIS information. Unlike most other Tulip-like chips, the X3201-3 requires that transmit buffers be aligned to a 4-byte boundary. This virtually ensures that each outgoing packet must be copied into an aligned buffer, since the Ethernet header is 14 bytes long.
This chip also supports ACPI power management.
This chip is found in Xircom RealPort(tm) 10/100 CardBus Ethernet/Modem cards, as well as some Intel OEM'd RealPort(tm) and IBM Etherjet cards.
Davicom DM9102 and DM9102A -- These chips are 21104A-like with a few minor exceptions. Media is provided by an internal IEEE 802.3u-compliant PHY accessed as if it were connected to a normal MII interface. The DM9102A also provides an external MII interface, to which a HomePNA 1 PHY is typically connected. The DM9102A also includes support for CardBus.
This chip also supports ACPI power management and Wake-On-LAN.
A complete list of boards with the DM9102 and DM9102A is not available. However, the DM9102 is often found on PC motherboards that include a built-in Ethernet interface.
ASIX AX88140A and AX88141 -- These chips are 21143-like with some exceptions. Media is proved by an internal IEEE 802.3u-compliant PHY connected to an MII interface. Unlike most other Tulip-like chips, AX88140A and AX88141 both require that the transmit buffers be aligned to a 4-byte boundary.
It has a specific broadcast bit.
This chip also supports ACPI power management.
A list of boards which include the AX88140A or the AX88141 is not yet available.
Conexant RS7112 (LANfinity) -- These chips are 21143 clones with coupled modem function. Media is provided by an IEEE 802.3u-compliant PHY connected to an MII interface.
A list of boards which include the RS7112 is not yet available.

MEDIA SELECTION

Media selection done using ifconfig(8) using the standard ifmedia(4) mechanism. Refer to those manual pages for more information.

HISTORY

The tlp driver first appeared in NetBSD 1.5.

AUTHORS

The tlp driver was written by Jason R. Thorpe while employed at the Numerical Aerospace Simulation Facility, NASA Ames Research Center. The author may be contacted at <thorpej@NetBSD.org>.

ASIX AX88140A and AX881401 support was added by Rui Paulo <rpaulo@NetBSD.org>.

Conexant RS7112 support was contributed by Frank Wille <frank@phoenix.owl.de>.

BUGS

Media autosense is not yet supported for any serial or PCS function media. It is, however, supported for IEEE 802.3u-compliant PHY media.

March 26, 2006

NetBSD 6.1