eri - eri Fast-Ethernet device driver
The eri Fast Ethernet driver is a multi-threaded, loadable,
clonable, STREAMS-based hardware driver supporting the con-
nectionless 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 initiali-
zation, 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 phy-
sical layer functions are provided by the internal tran-
sceiver which connects to a RJ-45 connector.
The 100Base-TX standard specifies an auto-negotiation proto-
col to automatically select the mode and speed of operation.
The internal transceiver 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 operation
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 initialized
on first attach and de-initialized (stopped) at last detach.
The values returned by the driver in the DL_INFO_ACK primi-
tive in response to the DL_INFO_REQ from the user are as
o The maximum SDU is 1500 (ETHERMTU - defined in
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
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," there-
fore valid values for the sap field are in the [0-0xFFFF]
range. Only one Ethernet type can be bound to the stream at
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 Ether-
net 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 par-
ticular 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 Ether-
net 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.
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 prim-
itives. 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 configura-
tions 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 Eth-
ernet 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
Once changed, all streams subsequently opened and attached
to this device will obtain this new physical address. Once
changed, the physical address will remain until this primi-
tive is used to change the physical address again or the
system is rebooted, whichever comes first.
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
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
o Advertises its capabilities to the Link Partner
o Selects the highest common denominator mode of opera-
tion 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 sup-
ports 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
The local transceiver has two set of capabilities: one set
reflects hardware capabilities, which are read-only (RO)
parameters. The second 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 capabili-
ties 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.
eri special character device.
System wide default device driver properties
64 bit device driver
ndd(1M), netstat(1M), driver.conf(4), hme(7D), qfe(7D),
Man(1) output converted with