The dnet Ethernet driver is a multithreaded, loadable, clonable, STREAMS GLD driver. Multiple controllers installed within the system are supported by the driver. The dnet driver functions include controller initialization, frame transmit and receive, functional addresses, promiscuous and multicast support, and error recovery and reporting.

The cloning character-special device, /dev/dnet, is used to access all DEC 21040/21041/21140 devices installed in the system.

The dnet driver is dependent on /kernel/misc/gld, a loadable kernel module that provides the dnet driver with the DLPI and STREAMS functionality required of a LAN driver. See gld(7D) for more details on the primitives supported by the driver.

The device is initialized on the first attach and de-initialized (stopped) on the last detach.

The values returned by the driver in the DL_INFO_ACK primitive in response to a DL_INFO_REQ from the user are as follows:

• The maximum SDU is 1500 (ETHERMTU - defined in <sys/ethernet.h>).
• The minimum SDU is 0.
• The DLSAP address length is 8.
• The MAC type is DL_ETHER.
• The sap length value is -2, meaning the physical address component is followed immediately by a 2-byte sap component within the DLSAP address.
• The broadcast address value is the Ethernet/IEEE broadcast address (FF:FF:FF:FF:FF:FF).

Once in the DL_ATTACHED state, the user must send a DL_BIND_REQ to associate a particular Service Access Point (SAP) with the stream.

The PCI configuration process varies from system to system. Follow the instructions provided by the vendor.

Known Problems and Limitations

The /kernel/drv/dnet.conf file supports the following options:

full-duplex

For full duplex operation use full-duplex=1, for half duplex use full-duplex=0. Half-duplex operation gives better results on older 10mbit networks.

speed

For 10mbit operation use speed=10, for 100mbit operation use speed=100. Certain 21140 based cards will operate at either speed. Use the speed property to override the 100mbit default in this case.

/dev/dnet

character special device

/kernel/drv/dnet.conf

dnet configuration file

See attributes(5) for descriptions of the following attributes:

attributes(5), dlpi(7P), gld(7D) streamio(7I)

Writing Device Drivers

STREAMS Programming Guide

Network Interfaces Programmer's Guide