[3c90x] Remove src/drivers/3c90x.txt

Most of the 3c90x.txt file is obsolete.  The content from the file has
been placed here:

   http://etherboot.org/wiki/appnotes/3c90x_issues

src/drivers/net/3c90x.txt

@@ -1,307 +0,0 @@
-
-	Instructions for use of the 3C90X driver for EtherBoot
-
-		Original 3C905B support by:
-			Greg Beeley (Greg.Beeley@LightSys.org),
-			LightSys Technology Services, Inc.
-			February 11, 1999
-
-		Updates for 3C90X family by:
-			Steve Smith (steve.smith@juno.com)
-			October 1, 1999
-
-		Minor documentation updates by
-			Greg Beeley (Greg.Beeley@LightSys.org)
-			March 29, 2000
-
--------------------------------------------------------------------------------
-
-I   OVERVIEW
-
-    The 3c90X series ethernet cards are a group of high-performance busmaster
-    DMA cards from 3Com.  This particular driver supports both the 3c90x and
-    the 3c90xB revision cards.  3C90xC family support has been tested to some
-    degree but not extensively.
-
-    Here's the licensing information:
-
-    This program Copyright (C) 1999 LightSys Technology Services, Inc.
-    Portions Copyright (C) 1999 Steve Smith.
-
-    This program may be re-distributed in source or binary form, modified,
-    sold, or copied for any purpose, provided that the above copyright message
-    and this text are included with all source copies or derivative works, and
-    provided that the above copyright message and this text are included in the
-    documentation of any binary-only distributions.  This program is
-    distributed WITHOUT ANY WARRANTY, without even the warranty of FITNESS FOR
-    A PARTICULAR PURPOSE or MERCHANTABILITY.  Please read the associated
-    documentation "3c90x.txt" before compiling and using this driver.
-
-
-II  FLASH PROMS
-
-    The 3c90xB cards, according to the 3Com documentation, only accept the
-    following flash memory chips:
-
-	Atmel AT29C512 (64 kilobyte)
-	Atmel AT29C010 (128 kilobyte)
-
-    The 3c90x cards, according to the 3Com documentation, accept the
-    following flash memory chips capacities:
-
-	64  kb (8 kB)
-	128 kb (16 kB)
-	256 kb (32 kB) and
-	512 kb (64 kB)
-
-    Atmel AT29C512 (64 kilobyte) chips are specifically listed for both
-    adapters, but flashing on the 3c905b cards would only be supported
-    through the Atmel parts.  Any device, of the supported size, should
-    be supported when programmed by a dedicated PROM programmer (e.g.
-    not the card).
-
-    To use this driver in such a PROM, visit Atmel's web site and download
-    their .PDF file containing a list of their distributors.  Contact the
-    distributors for pricing information.  The prices are quite reasonable
-    (about $3 US each for the 64 kB part), and are comparable to what one would
-    expect for similarly sized standard EPROMs.  And, the flash chips are much
-    easier to work with, as they don't need to be UV-erased to be reprogrammed.
-    The 3C905B card actually provides a method to program the flash memory
-    while it is resident on board the card itself; if someone would like to
-    write a small DOS program to do the programming, I can provide the
-    information about the registers and so forth.
-
-    A utility program, 3c90xutil, is provided with Etherboot in the 'contrib'
-    directory that allows for the on-board flashing of the ROM while Linux
-    is running.  The program has been successfully used under Linux, but I
-    have heard problem reports of its use under FreeBSD.  Anyone willing to
-    make it work under FreeBSD is more than welcome to do so!
-
-    You also have the option of using EPROM chips - the 3C905B-TX-NM has been
-    successfully tested with 27C256 (32kB) and 27C512 (64kB) chips with a
-    specified access time of 100ns and faster.
-
-
-III GENERAL USE
-
-    Normally, the basic procedure for using this driver is as follows:
-
-	1.  Run the 3c90xcfg program on the driver diskette to enable the
-	boot PROM and set it to 64k or 128k, as appropriate.
-	2.  Build the appropriate 3c90x.fd0 or 3c90x.fd0 floppy image with
-	possibly the value CFG_3C90X_XCVR defined to the transceiver type that
-	you want to use (i.e., 10/100 rj45, AUI, coax, MII).
-	3.  Run the floppy image on the PC to be network booted, to get
-	it configured, and to verify that it will boot properly.
-	4.  Build the 3c90x.rom or 3c90x.lzrom PROM image and program
-	it into the flash or EPROM memory chip.
-	5.  Put the PROM in the ethernet card, boot and enable 'boot from
-	network first' in the system BIOS, save and reboot.
-
-    Here are some issues to be aware of:
-
-	1.  If you experience crashes or different behaviour when using the
-	boot PROM, add the setting CFG_3C90X_BOOTROM_FIX and go through the
-	steps 2-5 above.  This works around a bug in some 3c905B cards (see
-	below), but has some side-effects which may not be desirable.
-        Please note that you have to boot off a floppy (not PROM!) once for
-        this fix to take effect.
-	2.  The possible need to manually set the CFG_3C90X_XCVR value to
-	configure the transceiver type.  Values are listed below.
-	3.  The possible need to define CFG_3C90X_PRESERVE_XCVR for use in
-	operating systems that don't intelligently determine the
-	transceiver type.
-
-    Some things that are on the 'To-Do' list, perhaps for me, but perhaps
-    for any other volunteers out there:
-
-	1.  Extend the driver to fully implement the auto-select
-	algorithm if the card has multiple media ports.
-	2.  Fix any bugs in the code <grin>....
-	3.  Extend the driver to support the 3c905c revision cards
-	"officially".  Right now, the support has been primarily empirical
-	and not based on 3c905C documentation.
-
-    Now for the details....
-
-    This driver has been tested on roughly 300 systems.  The main two
-    configuration issues to contend with are:
-
-	1.  Ensure that PCI Busmastering is enabled for the adapter (configured
-	in the CMOS setup)
-	2.  Some systems don't work properly with the adapter when plug and
-	play OS is enabled; I always set it to "No" or "Disabled" -- this makes
-	it easier and really doesn't adversely affect anything.
-
-    Roughly 95% of the systems worked when configured properly.  A few
-    have issues with booting locally once the boot PROM has been installed
-    (this number has been less than 2%).  Other configuration issues that
-    to check:
-
-	1.  Newer BIOS's actually work correctly with the network boot order.
-	Set the network adapter first.  Most older BIOS's automatically go to
-	the network boot PROM first.
-	2.  For systems where the adapter was already installed and is just
-	having the PROM installed, try setting the "reset configuration data"
-	to yes in the CMOS setup if the BIOS isn't seen at first.  If your BIOS
-	doesn't have this option, remove the card, start the system, shut down,
-	install the card and restart (or switch to a different PCI slot).
-	3.  Make sure the CMOS security settings aren't preventing a boot.
-
-    The 3c905B cards have a significant 'bug' that relates to the flash prom:
-    unless the card is set internally to the MII transceiver, it will only
-    read the first 8k of the PROM image.  Don't ask why -- it seems really
-    obscure, but it has to do with the way they mux'd the address lines
-    from the PCI bus to the ROM.  Unfortunately, most of us are not using
-    MII transceivers, and even the .lzrom image ends up being just a little
-    bit larger than 8k.  Note that the workaround for this is disabled by
-    default, because the Windows NT 4.0 driver does not like it (no packets
-    are transmitted).
-
-    So, the solution that I've used is to internally set the card's nvram
-    configuration to use MII when it boots.  The 3c905b driver does this
-    automatically.  This way, the 16k prom image can be loaded into memory,
-    and then the 3c905b driver can set the temporary configuration of the
-    card to an appropriate value, either configurable by the user or chosen
-    by the driver.
-
-    To enable the 3c905B bugfix, which is necessary for these cards when 
-    booting from the Flash ROM, define -DCFG_3C90X_BOOTROM_FIX when building,
-    create a floppy image and boot it once.
-    Thereafter, the card should accept the larger prom image.
-
-    The driver should choose an appropriate transceiver on the card.  However,
-    if it doesn't on your card or if you need to, for instance, set your
-    card to 10mbps when connected to an unmanaged 10/100 hub, you can specify
-    which transceiver you want to use.  To do this, build the 3c905b.fd0
-    image with -DCFG_3C90X_XCVR=x, where 'x' is one of the following
-    values:
-
-	0	10Base-T
-	1	10mbps AUI
-	3	10Base-2 (thinnet/coax)
-	4	100Base-TX
-	5	100Base-FX
-	6	MII
-	8	Auto-negotiation 10Base-T / 100Base-TX (usually the default)
-	9	MII External MAC Mode
-	255	Allow driver to choose an 'appropriate' media port.
-
-    Then proceed from step 2 in the above 'general use' instructions.  The
-    .rom image can be built with CFG_3C90X_XCVR set to a value, but you
-    normally don't want to do this, since it is easier to change the
-    transceiver type by rebuilding a new floppy, changing the BIOS to floppy
-    boot, booting, and then changing the BIOS back to network boot.  If
-    CFG_3C90X_XCVR is not set in a particular build, it just uses the
-    current configuration (either its 'best guess' or whatever the stored
-    CFG_3C90X_XCVR value was from the last time it was set).
-
-    [[ Note for the more technically inclined:  The CFG_3C90X_XCVR value is
-    programmed into a register in the card's NVRAM that was reserved for
-    LanWorks PROM images to use.  When the driver boots, the card comes
-    up in MII mode, and the driver checks the LanWorks register to find
-    out if the user specified a transceiver type.  If it finds that
-    information, it uses that, otherwise it picks a transceiver that the
-    card has based on the 3c905b's MediaOptions register.  This driver isn't
-    quite smart enough to always determine which media port is actually
-    _connected_; maybe someone else would like to take on that task (it
-    actually involves sending a self-directed packet and seeing if it
-    comes back.  IF it does, that port is connected). ]]
-
-    Another issue to keep in mind is that it is possible that some OS'es
-    might not be happy with the way I've handled the PROM-image hack with
-    setting MII mode on bootup.  Linux 2.0.35 does not have this problem.
-    Behavior of other systems may vary.  The 3com documentation specifically
-    says that, at least with the card that I have, the device driver in the
-    OS should auto-select the media port, so other drivers should work fine
-    with this 'hack'.  However, if yours doesn't seem to, you can try defining
-    CFG_3C90X_PRESERVE_XCVR when building to cause Etherboot to keep the
-    working setting (that allowed the bootp/tftp process) across the eth_reset
-    operation.
-
-
-IV  FOR DEVELOPERS....
-
-    If you would like to fix/extend/etc. this driver, feel free to do so; just
-    be sure you can test the modified version on the 3c905B-TX cards that the
-    driver was originally designed for.  This section of this document gives
-    some information that might be relevant to a programmer.
-
-    A.  Main Entry Point
-
-	a3c90x_probe is the main entry point for this driver.  It is referred
-	to in an array in 'config.c'.
-
-    B.  Other Important Functions
-
-	The functions a3c90x_transmit, a3c90x_poll, a3c90x_reset, and
-	a3c90x_disable are static functions that EtherBoot finds out about
-	as a  result of a3c90x_probe setting entries in the nic structure
-	for them.  The EtherBoot framework does not use interrupts.  It is
-	polled.  All transmit and receive operations are initiated by the
-	etherboot framework, not by an interrupt or by the driver.
-
-    C.  Internal Functions
-
-	The following functions are internal to the driver:
-
-	a3c90x_internal_IssueCommand - sends a command to the 3c905b card.
-	a3c90x_internal_SetWindow - shifts between one of eight register
-	windows onboard the 3c90x.  The bottom 16 bytes of the card's
-	I/O space are multiplexed among 128 bytes, only 16 of which are
-	visible at any one time.  This SetWindow function selects one of
-	the eight sets.
-	a3c90x_internal_ReadEeprom - reads a word (16 bits) from the
-	card's onboard nvram.  This is NOT the BIOS boot rom.  This is
-	where the card stores such things as its hardware address.
-	a3c90x_internal_WriteEeprom - writes a word (16 bits) to the
-	card's nvram, and recomputes the eeprom checksum.
-	a3c90x_internal_WriteEepromWord - writes a word (16 bits) to the
-	card's nvram.  Used by the above routine.
-	a3c90x_internal_WriteEepromWord - writes a word (16 bits) to the
-	card's nvram.  Used by the above routine.
-
-    D.  Globals
-
-	All global variables are inside a global structure named INF_3C90X.
-	So, wherever you see that structure referenced, you know the variable
-	is a global.  Just keeps things a little neater.
-
-    E.  Enumerations
-
-	There are quite a few enumerated type definitions for registers and
-	so forth, many for registers that I didn't even touch in the driver.
-	Register types start with 'reg', window numbers (for SetWindow)
-	start with 'win', and commands (for IssueCommand) start with 'cmd'.
-	Register offsets also include an indication in the name as to the
-	size of the register (_b = byte, _w = word, _l = long), and which
-	window the register is in, if it is windowed (0-7).
-
-    F.  Why the 'a3c90x' name?
-
-	I had to come up with a letter at the beginning of all of the
-	identifiers, since 3com so conveniently had their name start with a
-	number.  Another driver used 't' (for 'three'?); I chose 'a' for
-	no reason at all.
-
-Addendum by Jorge L. deLyra <delyra@latt.if.usp.br>, 22Nov2000 re
-working around the 3C905 hardware bug mentioned above:
-
-Use this floppy to fix any 3COM model 3C905B PCI 10/100 Ethernet cards
-that fail to load and run the boot program the first time around. If
-they have a "Lucent" rather than a "Broadcom" chipset these cards have
-a configuration bug that causes a hang when trying to load the boot
-program from the PROM, if you try to use them right out of the box.
-
-The boot program in this floppy is the file named 3c905b-tpo100.rom
-from Etherboot version 4.6.10, compiled with the bugfix parameter
-
-			CFG_3C90X_BOOTROM_FIX
-
-You have to take the chip off the card and boot the system once using
-this floppy. Once loaded from the floppy, the boot program will access
-the card and change some setting in it, correcting the problem. After
-that you may use either this boot program or the normal one, compiled
-without this bugfix parameter, to boot the machine from the PROM chip.
-
-[Any recent Etherboot version should do, not just 4.6.10 - Ed.]