qfe - SUNW,qfe Quad Fast-Ethernet device driver
The SUNW,qfe Quad Fast-Ethernet driver is a multi-threaded,
loadable, clonable, STREAMS hardware driver supporting the
connectionless Data Link Provider Interface, dlpi(7P), over
a SUNW,qfe Quad Fast-Ethernet controller. Multiple SUNW,qfe
controllers installed within the system are supported by the
driver. The qfe driver provides basic support for the
SUNW,qfe hardware. It is used to handle the SUNW,qfe dev-
ice. Functions include chip initialization, frame transit
and receive, multicast and promiscuous support, and error
recovery and reporting.
The SUNW,qfe device provides a 100Base-TX networking inter-
face. There are two types of SUNW,qfe device: one support-
ing Sbus and the other supporting the PCI bus interface. The
Sbus SUNW,qfe device uses Sun's FEPS ASIC, which provides
the Sbus interface and MAC functions. The PCI
SUNW,qfe device uses Sun's PFEX ASIC to provide the PCI
interface and MAC functions. Both connect with the 100Base-
TX on-board transceiver, which connects to a RJ45 connector
to provide the Physical layer functions and external con-
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/qfe is used to
access all SUNW,qfe controllers installed within the system.
qfe and DLPI
The qfe 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.
The driver returns an error (DL_ERROR_ACK) 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 service access pointer
SAP with the stream. The qfe 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 "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 multi-
ple 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 qfe 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 qfe
driver. The qfe 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 also supports the following primitives.
The DL_ENABMULTI_REQ and DL_DISABMULTI_REQ primitives enable
or 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. The driver accepts these primitives in any state
The DL_PROMISCON_REQ and DL_PROMISCOFF_REQ primitives with
the DL_PROMISC_PHYS flag set in the dl_level field enables
or disables reception of all frames on the media ("promis-
cuous mode"), including frames generated by the local host.
When used with the DL_PROMISC_SAP flag set this enables or
disables reception of all sap (Ethernet type) values. When
used with the DL_PROMISC_MULTI flag set this enables or dis-
ables 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 Eth-
ernet address currently associated (attached) to this
stream. The credentials of the process which originally
opened this stream must be root. 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 qfe driver performs "auto-negotiation" to
select the mode and speed of the link.
The link can be in one of the four following modes:
o 100 Mbps, full-duplex
o 100 Mbps, half-duplex
o 10 Mbps, full-duplex
o 10 Mbps, half-duplex
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.
o The highest priority is given to the 100 Mbps, full-
duplex; lowest priority is given to 10 Mbps, half-
The 100Base-TX transceiver is capable of all of the operat-
ing 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.
Sometimes, the user may want to select the speed and mode of
the link. The SUNW,qfe 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.
qfe Parameter List
The qfe driver provides for setting and getting various
parameters for the SUNW,qfe device. The parameter list
o current transceiver status
o current link status
o inter-packet gap
o local transceiver capabilities
o link partner capabilities
The local transceiver has two sets of capabilities: one set
reflects the capabilities of the hardware, which are read-
only (RO) parameters, and the second set, which reflects the
values chosen by the user, 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.
qfe 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