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+.. SPDX-License-Identifier: GPL-2.0
+
+=====================================================
+Notes on the DEC FDDIcontroller 700 (DEFZA-xx) driver
+=====================================================
+
+:Version: v.1.1.4
+
+
+DEC FDDIcontroller 700 is DEC's first-generation TURBOchannel FDDI
+network card, designed in 1990 specifically for the DECstation 5000
+model 200 workstation. The board is a single attachment station and
+it was manufactured in two variations, both of which are supported.
+
+First is the SAS MMF DEFZA-AA option, the original design implementing
+the standard MMF-PMD, however with a pair of ST connectors rather than
+the usual MIC connector. The other one is the SAS ThinWire/STP DEFZA-CA
+option, denoted 700-C, with the network medium selectable by a switch
+between the DEC proprietary ThinWire-PMD using a BNC connector and the
+standard STP-PMD using a DE-9F connector. This option can interface to
+a DECconcentrator 500 device and, in the case of the STP-PMD, also other
+FDDI equipment and was designed to make it easier to transition from
+existing IEEE 802.3 10BASE2 Ethernet and IEEE 802.5 Token Ring networks
+by providing means to reuse existing cabling.
+
+This driver handles any number of cards installed in a single system.
+They get fddi0, fddi1, etc. interface names assigned in the order of
+increasing TURBOchannel slot numbers.
+
+The board only supports DMA on the receive side. Transmission involves
+the use of PIO. As a result under a heavy transmission load there will
+be a significant impact on system performance.
+
+The board supports a 64-entry CAM for matching destination addresses.
+Two entries are preoccupied by the Directed Beacon and Ring Purger
+multicast addresses and the rest is used as a multicast filter. An
+all-multi mode is also supported for LLC frames and it is used if
+requested explicitly or if the CAM overflows. The promiscuous mode
+supports separate enables for LLC and SMT frames, but this driver
+doesn't support changing them individually.
+
+
+Known problems:
+
+None.
+
+
+To do:
+
+5. MAC address change. The card does not support changing the Media
+ Access Controller's address registers but a similar effect can be
+ achieved by adding an alias to the CAM. There is no way to disable
+ matching against the original address though.
+
+7. Queueing incoming/outgoing SMT frames in the driver if the SMT
+ receive/RMC transmit ring is full. (?)
+
+8. Retrieving/reporting FDDI/SNMP stats.
+
+
+Both success and failure reports are welcome.
+
+Maciej W. Rozycki <macro@linux-mips.org>