patch-2.4.17 linux/Documentation/networking/tulip.txt

• Lines: 227
• Date: Thu Jan 1 00:00:00 1970
• Orig file: linux-2.4.16/Documentation/networking/tulip.txt
• Orig date: Fri Mar 2 19:02:14 2001

diff -Naur -X /home/marcelo/lib/dontdiff linux-2.4.16/Documentation/networking/tulip.txt linux/Documentation/networking/tulip.txt
@@ -1,226 +0,0 @@
-                Tulip Ethernet Card Driver
-	  Maintained by Jeff Garzik <jgarzik@mandrakesoft.com>
-
-The Tulip driver was developed by Donald Becker and changed by
-Takashi Manabe and a cast of thousands.
-
-For 2.4.x and later kernels, the Linux Tulip driver is available at
-http://sourceforge.net/projects/tulip/
-
-	This driver is for the Digital "Tulip" Ethernet adapter interface.
-	It should work with most DEC 21*4*-based chips/ethercards, as well as
-	with work-alike chips from Lite-On (PNIC) and Macronix (MXIC) and ASIX.
-
-	The author may be reached as becker@scyld.com, or C/O
-	Center of Excellence in Space Data and Information Sciences
-	   Code 930.5, Goddard Space Flight Center, Greenbelt MD 20771
-
-	Additional information on Donald Becker's tulip.c
-	is available at http://www.scyld.com/network/tulip.html
-
-
-
-
-				Theory of Operation
-
-Board Compatibility
-===================
-
-This device driver is designed for the DECchip "Tulip", Digital's
-single-chip ethernet controllers for PCI.  Supported members of the family
-are the 21040, 21041, 21140, 21140A, 21142, and 21143.  Similar work-alike
-chips from Lite-On, Macronics, ASIX, Compex and other listed below are also
-supported.
-
-These chips are used on at least 140 unique PCI board designs.  The great
-number of chips and board designs supported is the reason for the
-driver size and complexity.  Almost of the increasing complexity is in the
-board configuration and media selection code.  There is very little
-increasing in the operational critical path length.
-
-Board-specific settings
-=======================
-
-PCI bus devices are configured by the system at boot time, so no jumpers
-need to be set on the board.  The system BIOS preferably should assign the
-PCI INTA signal to an otherwise unused system IRQ line.
-
-Some boards have EEPROMs tables with default media entry.  The factory default
-is usually "autoselect".  This should only be overridden when using
-transceiver connections without link beat e.g. 10base2 or AUI, or (rarely!)
-for forcing full-duplex when used with old link partners that do not do
-autonegotiation.
-
-Driver operation
-================
-
-Ring buffers
-------------
-
-The Tulip can use either ring buffers or lists of Tx and Rx descriptors.
-This driver uses statically allocated rings of Rx and Tx descriptors, set at
-compile time by RX/TX_RING_SIZE.  This version of the driver allocates skbuffs
-for the Rx ring buffers at open() time and passes the skb->data field to the
-Tulip as receive data buffers.  When an incoming frame is less than
-RX_COPYBREAK bytes long, a fresh skbuff is allocated and the frame is
-copied to the new skbuff.  When the incoming frame is larger, the skbuff is
-passed directly up the protocol stack and replaced by a newly allocated
-skbuff.
-
-The RX_COPYBREAK value is chosen to trade-off the memory wasted by
-using a full-sized skbuff for small frames vs. the copying costs of larger
-frames.  For small frames the copying cost is negligible (esp. considering
-that we are pre-loading the cache with immediately useful header
-information).  For large frames the copying cost is non-trivial, and the
-larger copy might flush the cache of useful data.  A subtle aspect of this
-choice is that the Tulip only receives into longword aligned buffers, thus
-the IP header at offset 14 isn't longword aligned for further processing.
-Copied frames are put into the new skbuff at an offset of "+2", thus copying
-has the beneficial effect of aligning the IP header and preloading the
-cache.
-
-Synchronization
----------------
-The driver runs as two independent, single-threaded flows of control.  One
-is the send-packet routine, which enforces single-threaded use by the
-dev->tbusy flag.  The other thread is the interrupt handler, which is single
-threaded by the hardware and other software.
-
-The send packet thread has partial control over the Tx ring and 'dev->tbusy'
-flag.  It sets the tbusy flag whenever it's queuing a Tx packet. If the next
-queue slot is empty, it clears the tbusy flag when finished otherwise it sets
-the 'tp->tx_full' flag.
-
-The interrupt handler has exclusive control over the Rx ring and records stats
-from the Tx ring.  (The Tx-done interrupt can't be selectively turned off, so
-we can't avoid the interrupt overhead by having the Tx routine reap the Tx
-stats.)	 After reaping the stats, it marks the queue entry as empty by setting
-the 'base' to zero.	 Iff the 'tp->tx_full' flag is set, it clears both the
-tx_full and tbusy flags.
-
-Notes
-=====
-
-Thanks to Duke Kamstra of SMC for long ago providing an EtherPower board.
-Greg LaPolla at Linksys provided PNIC and other Linksys boards.
-Znyx provided a four-port card for testing.
-
-References
-==========
-
-http://cesdis.gsfc.nasa.gov/linux/misc/NWay.html
-http://www.digital.com  (search for current 21*4* datasheets and "21X4 SROM")
-http://www.national.com/pf/DP/DP83840A.html
-http://www.asix.com.tw/pmac.htm
-http://www.admtek.com.tw/
-
-Errata
-======
-
-The old DEC databooks were light on details.
-The 21040 databook claims that CSR13, CSR14, and CSR15 should each be the last
-register of the set CSR12-15 written.  Hmmm, now how is that possible?
-
-The DEC SROM format is very badly designed not precisely defined, leading to
-part of the media selection junkheap below.  Some boards do not have EEPROM
-media tables and need to be patched up.  Worse, other boards use the DEC
-design kit media table when it isn't correct for their board.
-
-We cannot use MII interrupts because there is no defined GPIO pin to attach
-them.  The MII transceiver status is polled using an kernel timer.
-
-
-Source tree tour
-================
-The following is a list of files comprising the Tulip ethernet driver in
-drivers/net/tulip subdirectory.
-
-21142.c		- 21142-specific h/w interaction
-eeprom.c	- EEPROM reading and parsing
-interrupt.c	- Interrupt handler
-media.c		- Media selection and MII support
-pnic.c		- PNIC-specific h/w interaction
-timer.c		- Main driver timer, and misc h/w timers
-tulip.h		- Private driver header
-tulip_core.c	- Driver core (a.k.a. where "everything else" goes)
-
-
-
-Version history
-===============
-0.9.14 (February 20, 2000):
-* Fix PNIC problems (Manfred Spraul)
-* Add new PCI id for Accton comet
-* Support Davicom tulips
-* Fix oops in eeprom parsing
-* Enable workarounds for early PCI chipsets
-* IA64, hppa csr0 support
-* Support media types 5, 6
-* Interpret a bit more of the 21142 SROM extended media type 3
-* Add missing delay in eeprom reading
-
-0.9.11 (November 3, 2000):
-* Eliminate extra bus accesses when sharing interrupts (prumpf)
-* Barrier following ownership descriptor bit flip (prumpf)
-* Endianness fixes for >14 addresses in setup frames (prumpf)
-* Report link beat to kernel/userspace via netif_carrier_*. (kuznet)
-* Better spinlocking in set_rx_mode.
-* Fix I/O resource request failure error messages (DaveM catch)
-* Handle DMA allocation failure.
-
-0.9.10 (September 6, 2000):
-* Simple interrupt mitigation (via jamal)
-* More PCI ids
-
-0.9.9 (August 11, 2000):
-* More PCI ids
-
-0.9.8 (July 13, 2000):
-* Correct signed/unsigned comparison for dummy frame index
-* Remove outdated references to struct enet_statistics
-
-0.9.7 (June 17, 2000):
-* Timer cleanups (Andrew Morton)
-* Alpha compile fix (somebody?)
-
-0.9.6 (May 31, 2000):
-* Revert 21143-related support flag patch
-* Add HPPA/media-table debugging printk
-
-0.9.5 (May 30, 2000):
-* HPPA support (willy@puffingroup)
-* CSR6 bits and tulip.h cleanup (Chris Smith)
-* Improve debugging messages a bit
-* Add delay after CSR13 write in t21142_start_nway
-* Remove unused ETHER_STATS code
-* Convert 'extern inline' to 'static inline' in tulip.h (Chris Smith)
-* Update DS21143 support flags in tulip_chip_info[]
-* Use spin_lock_irq, not _irqsave/restore, in tulip_start_xmit()
-* Add locking to set_rx_mode()
-* Fix race with chip setting DescOwned bit (Hal Murray)
-* Request 100% of PIO and MMIO resource space assigned to card
-* Remove error message from pci_enable_device failure
-
-0.9.4.3 (April 14, 2000):
-* mod_timer fix (Hal Murray)
-* PNIC2 resuscitation (Chris Smith)
-
-0.9.4.2 (March 21, 2000):
-* Fix 21041 CSR7, CSR13/14/15 handling
-* Merge some PCI ids from tulip 0.91x
-* Merge some HAS_xxx flags and flag settings from tulip 0.91x
-* asm/io.h fix (submitted by many) and cleanup
-* s/HAS_NWAY143/HAS_NWAY/
-* Cleanup 21041 mode reporting
-* Small code cleanups
-
-0.9.4.1 (March 18, 2000):
-* Finish PCI DMA conversion (davem)
-* Do not netif_start_queue() at end of tulip_tx_timeout() (kuznet)
-* PCI DMA fix (kuznet)
-* eeprom.c code cleanup
-* Remove Xircom Tulip crud
-
-
-[EOF]
-