This page contains information on using Linux with the DEC 21040/21041/21140/21142/21143 "Tulip" chips, as used on the SMC PCI EtherPower and many other ethercards. This device driver also supports work-alike chips from LiteOn, ASIX, and MXIC, and relabeled PNIC chips from LinkSys and Netgear. The master copy of this page resides on the CESDIS WWW server.
See also the
The driver for the DEC "Tulip" series chips is available from this web page. It has been integrated with the kernel source tree since 1.1.90, although it remained commented out in the configuration file through 1.2.13. The driver version now available works with far more cards than the driver version available prior to kernel 2.0.31.
This driver was written to support the Beowulf cluster project at CESDIS. For Beowulf-specific information, read the Beowulf project description. Most of the current Beowulf cluster at least use one channel of Tulip-based Fast Ethernet.
Linux has a facility for linking device drivers into the running kernel. This is called Modules support. While probing for ISA devices at run time is a bad idea, some device drivers for PCI cards may be safely installed in this way. (And I'll even concede that it might be a Good Idea ;-)
Here's how to make and load the Modules version:
If you get an "linux/version.h no such file or directory" you either
have not installed the kernel source code, or you haven't run
cd /usr/src/linux; make include/linux/version.hyet. Some distributions allow you to install just the essential header files of the kernel source code, including a pre-built "version.h", so this isn't always necessary.
When using multiport cards with some (brain-damaged, but technically not broken) PCI BIOSes the Tulip chips are detected in reverse order. This isn't a problem if where all chips have individual address EEPROMs, but some multiport cards have only a single EEPROM on the "first" chip which is now detected last. The current work-around is implemented by compiling the driver with '-DREVERSE_PROBE_ORDER=1'.
When loaded as a module the following variables may be set:
name type description debug int The debug message level, 0 (no messages) to 6 (wordy). options int The media type override and card operation settings. (See below.) Add 16 or 0x10 for full duplex.Valid media types are:
|0||Auto-select (default to the 10baseT link)|
|12||10baseT (no autoselect), v0.69 and later only|
Notes: Not all cards can have their media type set with 'options'. Many cards support multiple media types with a single MII transceiver, and must always be set to an MII type (preferably 11, but other values 9-15 advertise only a single capability).
An example of loading the Tulip module is insmod tulip.o debug=1 options=0,16 This sets the debug message level to minimal messages, sets the first card to the auto-sense the media type, and the second to forced-full-duplex. (Note: card ordering is set by the motherboard's PCI BIOS.)
Support for the Tulip driver is now being handled through the mailing lists email@example.com for news general information and firstname.lastname@example.org for bug reports and problems.
To subscribe to a list, send a message with the contents "subscribe" e.g.:
A diagnostic program is available to help debug media selection and board-setup problems.
Due inaccurate documentation, autonegotiation cannot be enabled on the PNIC chip.
Most Ethernet chips can match a single unicast address -- their own station address -- and support a statistical (aka hash) filter for initial filtering of unwanted multicast packets. This is typically done by taking the CRC intermediate result just after destination address arrives, and using a few bits as the index into a table of which multicast packets are acceptable. The typical chip has 64 bins and uses six bits of CRC.
The Tulip does much better than this. The typical operating mode is matching the incoming destination address against a list of 16 addresses. After reserving two entries for the broadcast and station address, that means up to 14 multicast addresses may be perfectly filtered. With more than 14 multicast addresses the chip matches against a single unicast address and uses a statistical multicast filter with 512 bins, resulting in much better filtering than the 64 bin chips.
The new driver automatically switches media types attempting to find a valid selection. 21040 boards start with the 10baseT port, and switch to the AUI (usually 10base2) media if no link beat is detected. 21041 boards rotate among 10baseT, 10base2 and AUI connectors looking for activity. 21140 and later boards use the EEPROM information to select and switch among media types. If there is no valid EEPROM media table (i.e. a old board design), the driver uses an internal table based on the ethernet address prefix. If no internal table is found, the driver configures the chip to use an MII transceiver.
Macronix network products web page, http://www.mxic.com.tw/publish/2276.htm.
Many Ethernet adapter cards use the Tulip chip. The list grows so rapidly that it's impossible to keep up to date, but here are cards that I have received reports on:
is located at the
Goddard Space Flight Center in Greenbelt MD.