nei(7D)

NAME

nei − Novell NE2000, NE2000plus Ethernet device Driver

SYNOPSIS

/dev/nei

AVAILABILITY

x86

DESCRIPTION

The nei Ethernet driver is a multi-threaded, loadable, clonable, STREAMS hardware driver supporting the connectionless Data Link Provider Interface, dlpi(7P), over Novell NE2000 and NE2000plus controllers. The nei driver provides basic support for the NE2000 and NE2000plus hardware. Functions include chip initialization, frame transmit and receive, multicast and “promiscuous” support, and error recovery and reporting. Multiple NE2000 and NE2000plus controllers installed within the system are supported by the driver.

APPLICATION PROGRAMMING INTERFACE

The cloning, character-special device /dev/nei is used to access all NE2000 series devices installed within the system.

nei and DLPI

The nei driver is a “style 2” Data Link Service provider. All M_PROTO and M_PCPROTO type messages are interpreted as DLPI primitives. Valid DLPI primitives are defined in <sys/dlpi.h>. An explicit DL_ATTACH_REQ message by the user is required to associate the opened stream with a particular device (ppa). The ppa ID is interpreted as an unsigned long integer and indicates the corresponding device instance (unit) number. The unit numbers are assigned sequentially to each board found. The search order is determined by the order defined in the nei.conf file. An error (DL_ERROR_ACK) is returned by the driver if the ppa field value does not correspond to a valid device instance number for this system. The device is initialized on first attach and de-initialized (stopped) on last detach.

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

• The maximum Service Data Unit (SDU) is 1500 (ETHERMTU - defined in <sys/ethernet.h>).

• The minimum SDU is 0. The driver will pad to the mandatory 60-octet minimum packet size.

• The dlsap address length is 8.

• The Media Access Control (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 service mode is DL_CLDLS.

• No optional quality of service (QOS) support is included at present, so the QOS fields are 0.

• The provider style is DL_STYLE2.

• The version is DL_VERSION_2.

• The broadcast address value is 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 Pointer (SAP) with the stream. The nei driver interprets the sap field within the DL_BIND_REQ as an Ethernet “type”; therefore, valid values for the sap field are in the [0-0xFFFF] range. Only one Ethernet type can be bound to the stream at any time.

In addition to Ethernet V2 service, an “802.3 mode” is also provided by the driver. In this mode, sap values in the range [0-1500] are treated as equivalent and represent a desire by the user for “802.3 mode”. If the value of the sap field of the DL_BIND_REQ is within this range, then the driver expects that the destination DLSAP in a DL_UNITDATA_REQ will contain the length of the data rather than a sap value. All frames received from the media that have a “type” field in this range are assumed to be 802.3 frames, and they are routed up all open streams which are bound to any sap value within this range. If more than one stream is in “802.3 mode”, then the frame will be duplicated and routed up multiple streams as DL_UNITDATA_IND messages.

The nei driver DLSAP address format consists of the 6-byte physical (Ethernet) address component followed immediately by the 2-byte sap (type) component, producing an 8-byte DLSAP address. Applications should not hardcode to this particular implementation-specific DLSAP address format, but should instead use information returned in the DL_INFO_ACK primitive to compose and decompose DLSAP addresses. The sap length, full DLSAP length, and sap/physical ordering are included within the DL_INFO_ACK. The physical address length can be computed by subtracting the sap length from the full DLSAP address length or by issuing the DL_PHYS_ADDR_REQ to obtain the current physical address associated with the stream.

Once in the DL_BOUND state, the user may transmit frames on the Ethernet by sending DL_UNITDATA_REQ messages to the nei driver. The nei driver will route received Ethernet frames up all open and bound streams that have a sap which matches the Ethernet type as DL_UNITDATA_IND messages. Received Ethernet frames are duplicated and routed up multiple open streams if necessary. The DLSAP address contained within the DL_UNITDATA_REQ and DL_UNITDATA_IND messages consists of both the sap (type) and physical (Ethernet) components.

nei Primitives

In addition to the mandatory connectionless DLPI message set, the driver also supports the following primitives:

The DL_ENABMULTI_REQ and DL_DISABMULTI_REQ primitives enable/disable reception of individual multicast group addresses. A set of multicast addresses may be iteratively created and modified on a per-stream basis using these primitives. These primitives are accepted by the driver in any state following DL_ATTACHED.

The DL_PROMISCON_REQ and DL_PROMISCOFF_REQ primitives with the DL_PROMISC_PHYS flag set in the dl_level field enables/disables reception of all “promiscuous mode” frames on the media including frames generated by the local host.

When used with the DL_PROMISC_SAP flag set, this enables/disables reception of all sap (Ethernet type) values. When used with the DL_PROMISC_MULTI flag set, this enables/disables reception of all multicast group addresses. The effect of each is always on a per-stream basis and independent of the other sap and physical level configurations on this stream or other streams.

The DL_PHYS_ADDR_REQ primitive returns the 6-octet Ethernet address currently associated (attached) to the stream in the DL_PHYS_ADDR_ACK primitive. This primitive is valid only in states following a successful DL_ATTACH_REQ.

The DL_SET_PHYS_ADDR_REQ primitive changes the 6-octet Ethernet address currently associated (attached) to this stream. The credentials of the process which originally opened this stream must be superuser or an EPERM error is returned in the DL_ERROR_ACK. This primitive is destructive in that it affects all other current and future streams attached to this device. An M_ERROR is sent up all other streams attached to this device when this primitive on this stream is successful. Once changed, all streams subsequently opened and attached to this device will obtain this new physical address. The new physical address will remain in effect until this primitive is used to change the physical address again or the system is rebooted, whichever comes first.

CONFIGURATION

nei.conf is the configuration file for the nei device driver. The nei.conf file supports the following options:

intr Specifies the IRQ level for the board.

ioaddr Specifies the iobase address for the board.

reg Specifies the physical address and length in bytes of the device’s memory-mapped address space. These are valid in shared memory mode.

mode Specifies the operating mode (shared memory or I/O mode) for the device. "smmode" specifies shared memory for the NE2000plus board; any other value defaults to I/O mode. The NE2000 board always defaults to I/O mode.

The nei driver supports the use of shared RAM only on NE2000plus boards. It is important to ensure that there are no conflicts for the board’s I/O port, shared RAM , or IRQ level. See the Solaris 2.4 x86 Driver Update Guide for additional restrictions on configuring the NE2000 and other Ethernet cards in the same system.

FILES

/dev/nei nei character special device

/kernel/drv/nei nei device driver

/kernel/drv/nei.conf
configuration file of nei driver

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