hme - SUNW,hme Fast-Ethernet device driver
The SUNW,hme Fast-Ethernet driver is a multi-threaded,
loadable, clonable, STREAMS hardware driver supporting the
connectionless Data Link Provider Interface, dlpi(7P), over
a SUNW,hme Fast-Ethernet controller. The motherboard and
add-in SBus SUNW,hme controllers of several varieties are
supported. Multiple SUNW,hme controllers installed within
the system are supported by the driver.
The hme driver provides basic support for the SUNW,hme
hardware. It is used to handle the SUNW,hme device. Func-
tions include chip initialization, frame transit and
receive, multicast and promiscuous support, and error
recovery and reporting. SUNW,hme The SUNW,hme device pro-
vides 100Base-TX networking interfaces using SUN's FEPS ASIC
and an Internal Transceiver. The FEPS ASIC provides the Sbus
interface and MAC functions and the Physical layer functions
are provided by the Internal Transceiver which connects to a
RJ-45 connector. In addition to the RJ-45 connector, an MII
(Media Independent Interface) connector is also provided on
all SUNW,hme devices except the SunSwith SBus adapter
board. The MII interface is used to connect to an External
Transceiver which may use any physical media (copper or
fiber) specified in the 100Base-TX standard. When an Exter-
nal Transceiver is connected to the MII, the driver selects
the External Transceiver and disables the Internal Tran-
The 100Base-TX standard specifies an "auto-negotiation" pro-
tocol to automatically select the mode and speed of opera-
tion. The Internal transceiver is capable of doing "auto-
negotiation" with 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 forced-mode of operation
where the driver can select the mode of operation.
APPLICATION PROGRAMMING INTERFACE
The cloning character-special device /dev/hme is used to
access all SUNW,hme controllers installed within the system.
hme and DLPI
The hme 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 long 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 No optional quality of service (QOS) support is
included at present so the QOS fields are 0.
o The provider style is DL_STYLE2.
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 hme 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
If the user selects a sap with a value of 0, the receiver
will be in "802.3 mode". All frames received from the media
having a "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" then 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 if the sap value is 0, and if the destination
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 hme 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 use infor-
mation 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 hme
driver. The hme driver will route received Ethernet frames
up all those 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 multi-
ple open streams if necessary. The DLSAP address contained
within the DL_UNITDATA_REQ and DL_UNITDATA_IND messages con-
sists of both the sap (type) and physical (Ethernet) com-
In addition to the mandatory connectionless DLPI message set
the driver additionally 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. Otherwise EPERM 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 is suc-
cessful on this stream. Once changed, all streams subse-
quently opened and attached to this device will obtain this
new physical address. Once changed, the physical address
will remain until this primitive is used to change the phy-
sical address again or the system is rebooted, whichever
By default, the hme driver performs "auto-negotiation" to
select the mode and speed of the link, when the Internal
Transceiver is used.
When an External Transceiver is connected to the MII inter-
face, the driver selects the External Transceiver for net-
working operations. If the External Transceiver supports
"auto-negotiation", the driver uses the auto-negotiation
procedure to select the link speed and mode. If the External
Transceiver does not support auto-negotiation, it will
select the highest priority mode supported by the tran-
o 100 Mbps, full-duplex
o 100 Mbps, half-duplex
o 10 Mbps, full-duplex
o 10 Mbps, half-duplex
The link can be in one of the 4 following modes:
These speeds and modes are described in the 100Base-TX stan-
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 the 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. When the internal transceiver
is used, by default, auto-negotiation is used to select the
speed and the mode of the link and the common mode of opera-
tion with the Link Partner.
When an external transceiver is connected to the MII inter-
face, the driver selects the external transceiver for net-
working operations. If the external transceiver supports
o The driver uses the auto-negotiation procedure to
select the link speed and mode.
If the external transceiver does not support auto-
o The driver selects the highest priority mode supported
by the transceiver.
Sometimes, the user may want to select the speed and mode of
the link. The SUNW,hme device supports programmable "IPG"
(Inter-Packet Gap) parameters ipg1 and ipg2. By default,
the driver sets ipg1 to 8 byte-times and ipg2 to 4 byte-
times (which are the standard values). 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.
hme Parameter List
The hme driver provides for setting and getting various
parameters for the SUNW,hme device. The parameter list
current transceiver status
current link status
local transceiver capabilities
link partner capabilities
The local transceiver has two set of capabilities: one set
reflects the capabilities of the hardware, which are read-
only (RO) parameters and the second set reflects the values
chosen by the user and is used in speed selection. There
are read/write (RW) capabilities. At boot time, these two
sets of capabilities will be the same. The Link Partner
capabilities are also read only parameters because the
current default value of these parameters can only be read
and cannot be modified.
hme special character device
System-wide default device driver properties
ndd(1M), netstat(1M), driver.conf(4), dlpi(7P), le(7D)
Man(1) output converted with