qfe(7d) Devices qfe(7d)NAMEqfe - SUNW,qfe Quad Fast-Ethernet device driver
SYNOPSIS
/dev/qfe
DESCRIPTION
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 device. Func‐
tions include chip initialization, frame transit and receive, multicast
and promiscuous support, and error recovery and reporting.
SUNW,qfe
The SUNW,qfe device provides a 100Base-TX networking interface. There
are two types of SUNW,qfe device: one supporting 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 func‐
tions and external connection.
The 100Base-TX standard specifies an "auto-negotiation" protocol to
automatically select the mode and speed of operation. 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 cor‐
responding 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 primitive in
response to the DL_INFO_REQ from the user are as follows:
· The maximum SDU is 1500 (ETHERMTU - defined in <sys/ethernet.h>).
· The minimum SDU is 0.
· The dlsap address length is 8.
· The MAC type is DL_ETHER.
·
The sap length values 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
(0xFFFFFF).
Once in the DL_ATTACHED state, the user must send a DL_BIND_REQ to as‐
sociate a particular service access pointer SAP with the stream. The
qfe driver interprets the sap field within the DL_BIND_REQ as an Ether‐
net "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 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 mes‐
sage, not including initial M_PROTO mblk (message block), of all subse‐
quent 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 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 Ether‐
net 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 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.
qfe 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 primitives. The driver accepts these primitives 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 or disables
reception of all frames on the media ("promiscuous 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 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 success‐
ful 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 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 successful on this stream. 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 primitive is used to change the physical address
again or the system is rebooted, whichever comes first.
qfe Driver
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:
· 100 Mbps, full-duplex
· 100 Mbps, half-duplex
· 10 Mbps, full-duplex
· 10 Mbps, half-duplex
These speeds and modes are described in the 100Base-TX standard.
The auto−negotiation protocol automatically selects:
· Operation mode (half-duplex or full-duplex)
· Speed (100 Mbps or 10 Mbps)
The auto−negotiation protocol does the following:
· Gets all the modes of operation supported by the Link Partner
· Advertises its capabilities to the Link Partner
· Selects the highest common denominator mode of operation based on
the priorities.
·
The highest priority is given to the 100 Mbps, full-duplex; lowest
priority is given to 10 Mbps, half-duplex.
The 100Base-TX 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.
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). Some‐
times, 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 includes:
· current transceiver status
· current link status
· inter-packet gap
· local transceiver capabilities
· 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 modi‐
fied.
FILES
/dev/qfe qfe special character device
/kernel/drv/qfe.conf system wide default device driver properties
SEE ALSOndd(1M), netstat(1M), driver.conf(4), dlpi(7P)SunOS 5.10 6 May 1998 qfe(7d)
