eri(7D) 							      Devices								   eri(7D)

NAME

       eri - eri Fast-Ethernet device driver

SYNOPSIS

       /dev/eri

DESCRIPTION

       The  eri  Fast  Ethernet  driver is a multi-threaded, loadable, clonable, STREAMS--based hardware driver supporting the connectionless Data
       Link Provider Interface dlpi(7P) over an eri Fast-Ethernet controller. Multiple eri devices installed within the system	are  supported	by
       the driver.

       The eri driver provides basic support for the eri hardware and handles the eri device. Functions include chip initialization, frame transit
       and receive, multicast and promiscuous support, and error recovery and reporting.

       The eri device provides 100Base-TX networking interfaces using the SUN RIO ASIC and an internal transceiver. The RIO ASIC provides the  PCI
       interface and MAC functions.  The physical layer functions are provided by the internal transceiver which connects to a RJ-45 connector.

       The 100Base-TX standard specifies an auto-negotiation protocol to automatically select the mode and speed of operation. The internal trans-
       ceiver is capable of performing auto-negotiation using the remote-end of the link (link partner) and  receives  the  capabilities   of  the
       remote  end. It selects the  highest common denominator mode of operation based on the priorities. It also supports a forced-mode of opera-
       tion under which the driver selects the mode of operation.

APPLICATION PROGRAMMING INTERFACE

       The cloning character-special device  /dev/eri is used to access all eri controllers installed within the system.

   eri and DLPI
       The  eri 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>. Refer to dlpi(7P) for more information.

       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 integer data type and indicates the corresponding device instance (unit)  number.  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 initial-
       ized on first attach and de-initialized (stopped) at 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:

	 o  The maximum SDU is 1500 (ETHERMTU - defined in  <sys/ethernet.h> ).

	 o  The minimum SDU is 0.

	 o  The dlsap address length is 8.

	 o  The MAC type is DL_ETHER.

	 o  The sap length values is -2, meaning the physical address component is followed immediately  by a 2  byte  sap  component  within  the
	    DLSAP address.

	 o  The service mode is DL_CLDLS.

	 o  Optional quality of service (QOS) is not currently supported so  QOS fields are 0.

	 o  The provider style is DL_STYLE.

	 o  The version is DL_VERSION_2.

	 o  The broadcast address value is Ethernet/IEEE broadcast address(0xFFFFFF).

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

       If  the user selects a sap with a value of 0, the receiver will be in IEEE 802.3 mode. All frames received from the media having a Ethernet
       type field in the range [0-1500] are assumed to be 802.3 frames and are routed up all open Streams which are bound to sap value 0. If  more
       than one Stream is in 802.3 mode, the frame will be duplicated and routed up multiple Streams as DL_UNITDATA_IND messages.

       In  transmission, the driver checks the sap field of the DL_BIND_REQ to determine if the value is 0 or if the Ethernet type field is in the
       range [0-1500]. If either is true, the driver computes the length of the message, not including initial M_PROTO mblk  (message  block),	of
       all subsequent DL_UNITDATA_REQ messages, and transmits 802.3 frames that have this value in the MAC frame header length field.

       The  eri  driver's 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  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  eri  driver.  The  eri
       driver  will  route  received Ethernet frames up all open and bound streams having 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.

   eri 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 EPERM is returned in the DL_ERROR_ACK. This primitive is destructive
       because it affects all current and future streams attached to this device. An  M_ERROR is sent up all other streams attached to this device
       when this primitive is successful on this stream.
	Once changed, all streams subsequently opened and attached to this device will obtain this new physical address.  Once changed, the physi-
       cal address will remain until this primitive is used to change the physical address again or the system is rebooted, whichever comes first.

   eri DRIVER
       By default, the eri driver performs auto-negotiation to	select the mode and speed of the link, which can  be  in  one  of  the	 following
       modes, as described in the 100Base-TX standard:

	 o  100 Mbps, full-duplex

	 o  100 Mbps, half-duplex

	 o  10 Mbps, full-duplex

	 o  10 Mbps, half-duplex

       The auto-negotiation protocol automatically selects:

	 o  Operation mode (half-duplex or full-duplex)

	 o  Speed (100 Mbps or 10 Mbps)

       The auto-negotiation protocol does the following:

	 o
	    Gets all modes of operation supported by the link partner

	 o  Advertises its capabilities to the Link Partner

	 o  Selects the highest common denominator mode of operation based on the  priorities

       The  internal  transceiver is capable of all of the operating speeds and modes listed above. By default, auto-negotiation is used to select
       the speed and the mode of the link and the common mode of operation with the link partner.

       For users who want to select the speed and mode of  the link, the eri device supports programmable IPG (Inter-Packet Gap)  parameters  ipg1
       and  ipg2. Sometimes, the user may want to alter these values depending on whether the driver supports 10 Mbps or 100 Mpbs and accordingly,
       IPG will be set to 9.6 or 0.96 microseconds.

   eri Parameter List
       The eri driver provides for setting and getting various parameters for the  eri device. The parameter  list  includes  current  transceiver
       status, current link status, inter-packet gap, local transceiver capabilities and link partner capabilities.

       The  local transceiver has two set of capabilities: one set reflects  hardware capabilities, which are  read-only (RO) parameters. The sec-
       ond set reflects the values chosen by the user and is used in speed selection and possess read/write (RW) capability. At boot  time,  these
       two  sets  of  capabilities  will be the same. Because the current default value of these parameters can only be read and not modified, the
       link partner capabilities are also read only.

FILES

       /dev/eri 		       eri special character device.

       /kernel/drv/eri.conf		System wide default device driver properties

       /kernel/drv/sparcv9/eri		64 bit device driver

SEE ALSO

       ndd(1M), netstat(1M), driver.conf(4), hme(7D), qfe(7D), dlpi(7P)

SunOS 5.10							    1 Mar 2000								   eri(7D)