0001 .. SPDX-License-Identifier: GPL-2.0
0002
0003 ======
0004 ARCnet
0005 ======
0006
0007 .. note::
0008
0009 See also arcnet-hardware.txt in this directory for jumper-setting
0010 and cabling information if you're like many of us and didn't happen to get a
0011 manual with your ARCnet card.
0012
0013 Since no one seems to listen to me otherwise, perhaps a poem will get your
0014 attention::
0015
0016 This driver's getting fat and beefy,
0017 But my cat is still named Fifi.
0018
0019 Hmm, I think I'm allowed to call that a poem, even though it's only two
0020 lines. Hey, I'm in Computer Science, not English. Give me a break.
0021
0022 The point is: I REALLY REALLY REALLY REALLY REALLY want to hear from you if
0023 you test this and get it working. Or if you don't. Or anything.
0024
0025 ARCnet 0.32 ALPHA first made it into the Linux kernel 1.1.80 - this was
0026 nice, but after that even FEWER people started writing to me because they
0027 didn't even have to install the patch. <sigh>
0028
0029 Come on, be a sport! Send me a success report!
0030
0031 (hey, that was even better than my original poem... this is getting bad!)
0032
0033
0034 .. warning::
0035
0036 If you don't e-mail me about your success/failure soon, I may be forced to
0037 start SINGING. And we don't want that, do we?
0038
0039 (You know, it might be argued that I'm pushing this point a little too much.
0040 If you think so, why not flame me in a quick little e-mail? Please also
0041 include the type of card(s) you're using, software, size of network, and
0042 whether it's working or not.)
0043
0044 My e-mail address is: apenwarr@worldvisions.ca
0045
0046 These are the ARCnet drivers for Linux.
0047
0048 This new release (2.91) has been put together by David Woodhouse
0049 <dwmw2@infradead.org>, in an attempt to tidy up the driver after adding support
0050 for yet another chipset. Now the generic support has been separated from the
0051 individual chipset drivers, and the source files aren't quite so packed with
0052 #ifdefs! I've changed this file a bit, but kept it in the first person from
0053 Avery, because I didn't want to completely rewrite it.
0054
0055 The previous release resulted from many months of on-and-off effort from me
0056 (Avery Pennarun), many bug reports/fixes and suggestions from others, and in
0057 particular a lot of input and coding from Tomasz Motylewski. Starting with
0058 ARCnet 2.10 ALPHA, Tomasz's all-new-and-improved RFC1051 support has been
0059 included and seems to be working fine!
0060
0061
0062 Where do I discuss these drivers?
0063 ---------------------------------
0064
0065 Tomasz has been so kind as to set up a new and improved mailing list.
0066 Subscribe by sending a message with the BODY "subscribe linux-arcnet YOUR
0067 REAL NAME" to listserv@tichy.ch.uj.edu.pl. Then, to submit messages to the
0068 list, mail to linux-arcnet@tichy.ch.uj.edu.pl.
0069
0070 There are archives of the mailing list at:
0071
0072 http://epistolary.org/mailman/listinfo.cgi/arcnet
0073
0074 The people on linux-net@vger.kernel.org (now defunct, replaced by
0075 netdev@vger.kernel.org) have also been known to be very helpful, especially
0076 when we're talking about ALPHA Linux kernels that may or may not work right
0077 in the first place.
0078
0079
0080 Other Drivers and Info
0081 ----------------------
0082
0083 You can try my ARCNET page on the World Wide Web at:
0084
0085 http://www.qis.net/~jschmitz/arcnet/
0086
0087 Also, SMC (one of the companies that makes ARCnet cards) has a WWW site you
0088 might be interested in, which includes several drivers for various cards
0089 including ARCnet. Try:
0090
0091 http://www.smc.com/
0092
0093 Performance Technologies makes various network software that supports
0094 ARCnet:
0095
0096 http://www.perftech.com/ or ftp to ftp.perftech.com.
0097
0098 Novell makes a networking stack for DOS which includes ARCnet drivers. Try
0099 FTPing to ftp.novell.com.
0100
0101 You can get the Crynwr packet driver collection (including arcether.com, the
0102 one you'll want to use with ARCnet cards) from
0103 oak.oakland.edu:/simtel/msdos/pktdrvr. It won't work perfectly on a 386+
0104 without patches, though, and also doesn't like several cards. Fixed
0105 versions are available on my WWW page, or via e-mail if you don't have WWW
0106 access.
0107
0108
0109 Installing the Driver
0110 ---------------------
0111
0112 All you will need to do in order to install the driver is::
0113
0114 make config
0115 (be sure to choose ARCnet in the network devices
0116 and at least one chipset driver.)
0117 make clean
0118 make zImage
0119
0120 If you obtained this ARCnet package as an upgrade to the ARCnet driver in
0121 your current kernel, you will need to first copy arcnet.c over the one in
0122 the linux/drivers/net directory.
0123
0124 You will know the driver is installed properly if you get some ARCnet
0125 messages when you reboot into the new Linux kernel.
0126
0127 There are four chipset options:
0128
0129 1. Standard ARCnet COM90xx chipset.
0130
0131 This is the normal ARCnet card, which you've probably got. This is the only
0132 chipset driver which will autoprobe if not told where the card is.
0133 It following options on the command line::
0134
0135 com90xx=[<io>[,<irq>[,<shmem>]]][,<name>] | <name>
0136
0137 If you load the chipset support as a module, the options are::
0138
0139 io=<io> irq=<irq> shmem=<shmem> device=<name>
0140
0141 To disable the autoprobe, just specify "com90xx=" on the kernel command line.
0142 To specify the name alone, but allow autoprobe, just put "com90xx=<name>"
0143
0144 2. ARCnet COM20020 chipset.
0145
0146 This is the new chipset from SMC with support for promiscuous mode (packet
0147 sniffing), extra diagnostic information, etc. Unfortunately, there is no
0148 sensible method of autoprobing for these cards. You must specify the I/O
0149 address on the kernel command line.
0150
0151 The command line options are::
0152
0153 com20020=<io>[,<irq>[,<node_ID>[,backplane[,CKP[,timeout]]]]][,name]
0154
0155 If you load the chipset support as a module, the options are::
0156
0157 io=<io> irq=<irq> node=<node_ID> backplane=<backplane> clock=<CKP>
0158 timeout=<timeout> device=<name>
0159
0160 The COM20020 chipset allows you to set the node ID in software, overriding the
0161 default which is still set in DIP switches on the card. If you don't have the
0162 COM20020 data sheets, and you don't know what the other three options refer
0163 to, then they won't interest you - forget them.
0164
0165 3. ARCnet COM90xx chipset in IO-mapped mode.
0166
0167 This will also work with the normal ARCnet cards, but doesn't use the shared
0168 memory. It performs less well than the above driver, but is provided in case
0169 you have a card which doesn't support shared memory, or (strangely) in case
0170 you have so many ARCnet cards in your machine that you run out of shmem slots.
0171 If you don't give the IO address on the kernel command line, then the driver
0172 will not find the card.
0173
0174 The command line options are::
0175
0176 com90io=<io>[,<irq>][,<name>]
0177
0178 If you load the chipset support as a module, the options are:
0179 io=<io> irq=<irq> device=<name>
0180
0181 4. ARCnet RIM I cards.
0182
0183 These are COM90xx chips which are _completely_ memory mapped. The support for
0184 these is not tested. If you have one, please mail the author with a success
0185 report. All options must be specified, except the device name.
0186 Command line options::
0187
0188 arcrimi=<shmem>,<irq>,<node_ID>[,<name>]
0189
0190 If you load the chipset support as a module, the options are::
0191
0192 shmem=<shmem> irq=<irq> node=<node_ID> device=<name>
0193
0194
0195 Loadable Module Support
0196 -----------------------
0197
0198 Configure and rebuild Linux. When asked, answer 'm' to "Generic ARCnet
0199 support" and to support for your ARCnet chipset if you want to use the
0200 loadable module. You can also say 'y' to "Generic ARCnet support" and 'm'
0201 to the chipset support if you wish.
0202
0203 ::
0204
0205 make config
0206 make clean
0207 make zImage
0208 make modules
0209
0210 If you're using a loadable module, you need to use insmod to load it, and
0211 you can specify various characteristics of your card on the command
0212 line. (In recent versions of the driver, autoprobing is much more reliable
0213 and works as a module, so most of this is now unnecessary.)
0214
0215 For example::
0216
0217 cd /usr/src/linux/modules
0218 insmod arcnet.o
0219 insmod com90xx.o
0220 insmod com20020.o io=0x2e0 device=eth1
0221
0222
0223 Using the Driver
0224 ----------------
0225
0226 If you build your kernel with ARCnet COM90xx support included, it should
0227 probe for your card automatically when you boot. If you use a different
0228 chipset driver complied into the kernel, you must give the necessary options
0229 on the kernel command line, as detailed above.
0230
0231 Go read the NET-2-HOWTO and ETHERNET-HOWTO for Linux; they should be
0232 available where you picked up this driver. Think of your ARCnet as a
0233 souped-up (or down, as the case may be) Ethernet card.
0234
0235 By the way, be sure to change all references from "eth0" to "arc0" in the
0236 HOWTOs. Remember that ARCnet isn't a "true" Ethernet, and the device name
0237 is DIFFERENT.
0238
0239
0240 Multiple Cards in One Computer
0241 ------------------------------
0242
0243 Linux has pretty good support for this now, but since I've been busy, the
0244 ARCnet driver has somewhat suffered in this respect. COM90xx support, if
0245 compiled into the kernel, will (try to) autodetect all the installed cards.
0246
0247 If you have other cards, with support compiled into the kernel, then you can
0248 just repeat the options on the kernel command line, e.g.::
0249
0250 LILO: linux com20020=0x2e0 com20020=0x380 com90io=0x260
0251
0252 If you have the chipset support built as a loadable module, then you need to
0253 do something like this::
0254
0255 insmod -o arc0 com90xx
0256 insmod -o arc1 com20020 io=0x2e0
0257 insmod -o arc2 com90xx
0258
0259 The ARCnet drivers will now sort out their names automatically.
0260
0261
0262 How do I get it to work with...?
0263 --------------------------------
0264
0265 NFS:
0266 Should be fine linux->linux, just pretend you're using Ethernet cards.
0267 oak.oakland.edu:/simtel/msdos/nfs has some nice DOS clients. There
0268 is also a DOS-based NFS server called SOSS. It doesn't multitask
0269 quite the way Linux does (actually, it doesn't multitask AT ALL) but
0270 you never know what you might need.
0271
0272 With AmiTCP (and possibly others), you may need to set the following
0273 options in your Amiga nfstab: MD 1024 MR 1024 MW 1024
0274 (Thanks to Christian Gottschling <ferksy@indigo.tng.oche.de>
0275 for this.)
0276
0277 Probably these refer to maximum NFS data/read/write block sizes. I
0278 don't know why the defaults on the Amiga didn't work; write to me if
0279 you know more.
0280
0281 DOS:
0282 If you're using the freeware arcether.com, you might want to install
0283 the driver patch from my web page. It helps with PC/TCP, and also
0284 can get arcether to load if it timed out too quickly during
0285 initialization. In fact, if you use it on a 386+ you REALLY need
0286 the patch, really.
0287
0288 Windows:
0289 See DOS :) Trumpet Winsock works fine with either the Novell or
0290 Arcether client, assuming you remember to load winpkt of course.
0291
0292 LAN Manager and Windows for Workgroups:
0293 These programs use protocols that
0294 are incompatible with the Internet standard. They try to pretend
0295 the cards are Ethernet, and confuse everyone else on the network.
0296
0297 However, v2.00 and higher of the Linux ARCnet driver supports this
0298 protocol via the 'arc0e' device. See the section on "Multiprotocol
0299 Support" for more information.
0300
0301 Using the freeware Samba server and clients for Linux, you can now
0302 interface quite nicely with TCP/IP-based WfWg or Lan Manager
0303 networks.
0304
0305 Windows 95:
0306 Tools are included with Win95 that let you use either the LANMAN
0307 style network drivers (NDIS) or Novell drivers (ODI) to handle your
0308 ARCnet packets. If you use ODI, you'll need to use the 'arc0'
0309 device with Linux. If you use NDIS, then try the 'arc0e' device.
0310 See the "Multiprotocol Support" section below if you need arc0e,
0311 you're completely insane, and/or you need to build some kind of
0312 hybrid network that uses both encapsulation types.
0313
0314 OS/2:
0315 I've been told it works under Warp Connect with an ARCnet driver from
0316 SMC. You need to use the 'arc0e' interface for this. If you get
0317 the SMC driver to work with the TCP/IP stuff included in the
0318 "normal" Warp Bonus Pack, let me know.
0319
0320 ftp.microsoft.com also has a freeware "Lan Manager for OS/2" client
0321 which should use the same protocol as WfWg does. I had no luck
0322 installing it under Warp, however. Please mail me with any results.
0323
0324 NetBSD/AmiTCP:
0325 These use an old version of the Internet standard ARCnet
0326 protocol (RFC1051) which is compatible with the Linux driver v2.10
0327 ALPHA and above using the arc0s device. (See "Multiprotocol ARCnet"
0328 below.) ** Newer versions of NetBSD apparently support RFC1201.
0329
0330
0331 Using Multiprotocol ARCnet
0332 --------------------------
0333
0334 The ARCnet driver v2.10 ALPHA supports three protocols, each on its own
0335 "virtual network device":
0336
0337 ====== ===============================================================
0338 arc0 RFC1201 protocol, the official Internet standard which just
0339 happens to be 100% compatible with Novell's TRXNET driver.
0340 Version 1.00 of the ARCnet driver supported _only_ this
0341 protocol. arc0 is the fastest of the three protocols (for
0342 whatever reason), and allows larger packets to be used
0343 because it supports RFC1201 "packet splitting" operations.
0344 Unless you have a specific need to use a different protocol,
0345 I strongly suggest that you stick with this one.
0346
0347 arc0e "Ethernet-Encapsulation" which sends packets over ARCnet
0348 that are actually a lot like Ethernet packets, including the
0349 6-byte hardware addresses. This protocol is compatible with
0350 Microsoft's NDIS ARCnet driver, like the one in WfWg and
0351 LANMAN. Because the MTU of 493 is actually smaller than the
0352 one "required" by TCP/IP (576), there is a chance that some
0353 network operations will not function properly. The Linux
0354 TCP/IP layer can compensate in most cases, however, by
0355 automatically fragmenting the TCP/IP packets to make them
0356 fit. arc0e also works slightly more slowly than arc0, for
0357 reasons yet to be determined. (Probably it's the smaller
0358 MTU that does it.)
0359
0360 arc0s The "[s]imple" RFC1051 protocol is the "previous" Internet
0361 standard that is completely incompatible with the new
0362 standard. Some software today, however, continues to
0363 support the old standard (and only the old standard)
0364 including NetBSD and AmiTCP. RFC1051 also does not support
0365 RFC1201's packet splitting, and the MTU of 507 is still
0366 smaller than the Internet "requirement," so it's quite
0367 possible that you may run into problems. It's also slower
0368 than RFC1201 by about 25%, for the same reason as arc0e.
0369
0370 The arc0s support was contributed by Tomasz Motylewski
0371 and modified somewhat by me. Bugs are probably my fault.
0372 ====== ===============================================================
0373
0374 You can choose not to compile arc0e and arc0s into the driver if you want -
0375 this will save you a bit of memory and avoid confusion when eg. trying to
0376 use the "NFS-root" stuff in recent Linux kernels.
0377
0378 The arc0e and arc0s devices are created automatically when you first
0379 ifconfig the arc0 device. To actually use them, though, you need to also
0380 ifconfig the other virtual devices you need. There are a number of ways you
0381 can set up your network then:
0382
0383
0384 1. Single Protocol.
0385
0386 This is the simplest way to configure your network: use just one of the
0387 two available protocols. As mentioned above, it's a good idea to use
0388 only arc0 unless you have a good reason (like some other software, ie.
0389 WfWg, that only works with arc0e).
0390
0391 If you need only arc0, then the following commands should get you going::
0392
0393 ifconfig arc0 MY.IP.ADD.RESS
0394 route add MY.IP.ADD.RESS arc0
0395 route add -net SUB.NET.ADD.RESS arc0
0396 [add other local routes here]
0397
0398 If you need arc0e (and only arc0e), it's a little different::
0399
0400 ifconfig arc0 MY.IP.ADD.RESS
0401 ifconfig arc0e MY.IP.ADD.RESS
0402 route add MY.IP.ADD.RESS arc0e
0403 route add -net SUB.NET.ADD.RESS arc0e
0404
0405 arc0s works much the same way as arc0e.
0406
0407
0408 2. More than one protocol on the same wire.
0409
0410 Now things start getting confusing. To even try it, you may need to be
0411 partly crazy. Here's what *I* did. :) Note that I don't include arc0s in
0412 my home network; I don't have any NetBSD or AmiTCP computers, so I only
0413 use arc0s during limited testing.
0414
0415 I have three computers on my home network; two Linux boxes (which prefer
0416 RFC1201 protocol, for reasons listed above), and one XT that can't run
0417 Linux but runs the free Microsoft LANMAN Client instead.
0418
0419 Worse, one of the Linux computers (freedom) also has a modem and acts as
0420 a router to my Internet provider. The other Linux box (insight) also has
0421 its own IP address and needs to use freedom as its default gateway. The
0422 XT (patience), however, does not have its own Internet IP address and so
0423 I assigned it one on a "private subnet" (as defined by RFC1597).
0424
0425 To start with, take a simple network with just insight and freedom.
0426 Insight needs to:
0427
0428 - talk to freedom via RFC1201 (arc0) protocol, because I like it
0429 more and it's faster.
0430 - use freedom as its Internet gateway.
0431
0432 That's pretty easy to do. Set up insight like this::
0433
0434 ifconfig arc0 insight
0435 route add insight arc0
0436 route add freedom arc0 /* I would use the subnet here (like I said
0437 to in "single protocol" above),
0438 but the rest of the subnet
0439 unfortunately lies across the PPP
0440 link on freedom, which confuses
0441 things. */
0442 route add default gw freedom
0443
0444 And freedom gets configured like so::
0445
0446 ifconfig arc0 freedom
0447 route add freedom arc0
0448 route add insight arc0
0449 /* and default gateway is configured by pppd */
0450
0451 Great, now insight talks to freedom directly on arc0, and sends packets
0452 to the Internet through freedom. If you didn't know how to do the above,
0453 you should probably stop reading this section now because it only gets
0454 worse.
0455
0456 Now, how do I add patience into the network? It will be using LANMAN
0457 Client, which means I need the arc0e device. It needs to be able to talk
0458 to both insight and freedom, and also use freedom as a gateway to the
0459 Internet. (Recall that patience has a "private IP address" which won't
0460 work on the Internet; that's okay, I configured Linux IP masquerading on
0461 freedom for this subnet).
0462
0463 So patience (necessarily; I don't have another IP number from my
0464 provider) has an IP address on a different subnet than freedom and
0465 insight, but needs to use freedom as an Internet gateway. Worse, most
0466 DOS networking programs, including LANMAN, have braindead networking
0467 schemes that rely completely on the netmask and a 'default gateway' to
0468 determine how to route packets. This means that to get to freedom or
0469 insight, patience WILL send through its default gateway, regardless of
0470 the fact that both freedom and insight (courtesy of the arc0e device)
0471 could understand a direct transmission.
0472
0473 I compensate by giving freedom an extra IP address - aliased 'gatekeeper' -
0474 that is on my private subnet, the same subnet that patience is on. I
0475 then define gatekeeper to be the default gateway for patience.
0476
0477 To configure freedom (in addition to the commands above)::
0478
0479 ifconfig arc0e gatekeeper
0480 route add gatekeeper arc0e
0481 route add patience arc0e
0482
0483 This way, freedom will send all packets for patience through arc0e,
0484 giving its IP address as gatekeeper (on the private subnet). When it
0485 talks to insight or the Internet, it will use its "freedom" Internet IP
0486 address.
0487
0488 You will notice that we haven't configured the arc0e device on insight.
0489 This would work, but is not really necessary, and would require me to
0490 assign insight another special IP number from my private subnet. Since
0491 both insight and patience are using freedom as their default gateway, the
0492 two can already talk to each other.
0493
0494 It's quite fortunate that I set things up like this the first time (cough
0495 cough) because it's really handy when I boot insight into DOS. There, it
0496 runs the Novell ODI protocol stack, which only works with RFC1201 ARCnet.
0497 In this mode it would be impossible for insight to communicate directly
0498 with patience, since the Novell stack is incompatible with Microsoft's
0499 Ethernet-Encap. Without changing any settings on freedom or patience, I
0500 simply set freedom as the default gateway for insight (now in DOS,
0501 remember) and all the forwarding happens "automagically" between the two
0502 hosts that would normally not be able to communicate at all.
0503
0504 For those who like diagrams, I have created two "virtual subnets" on the
0505 same physical ARCnet wire. You can picture it like this::
0506
0507
0508 [RFC1201 NETWORK] [ETHER-ENCAP NETWORK]
0509 (registered Internet subnet) (RFC1597 private subnet)
0510
0511 (IP Masquerade)
0512 /---------------\ * /---------------\
0513 | | * | |
0514 | +-Freedom-*-Gatekeeper-+ |
0515 | | | * | |
0516 \-------+-------/ | * \-------+-------/
0517 | | |
0518 Insight | Patience
0519 (Internet)
0520
0521
0522
0523 It works: what now?
0524 -------------------
0525
0526 Send mail describing your setup, preferably including driver version, kernel
0527 version, ARCnet card model, CPU type, number of systems on your network, and
0528 list of software in use to me at the following address:
0529
0530 apenwarr@worldvisions.ca
0531
0532 I do send (sometimes automated) replies to all messages I receive. My email
0533 can be weird (and also usually gets forwarded all over the place along the
0534 way to me), so if you don't get a reply within a reasonable time, please
0535 resend.
0536
0537
0538 It doesn't work: what now?
0539 --------------------------
0540
0541 Do the same as above, but also include the output of the ifconfig and route
0542 commands, as well as any pertinent log entries (ie. anything that starts
0543 with "arcnet:" and has shown up since the last reboot) in your mail.
0544
0545 If you want to try fixing it yourself (I strongly recommend that you mail me
0546 about the problem first, since it might already have been solved) you may
0547 want to try some of the debug levels available. For heavy testing on
0548 D_DURING or more, it would be a REALLY good idea to kill your klogd daemon
0549 first! D_DURING displays 4-5 lines for each packet sent or received. D_TX,
0550 D_RX, and D_SKB actually DISPLAY each packet as it is sent or received,
0551 which is obviously quite big.
0552
0553 Starting with v2.40 ALPHA, the autoprobe routines have changed
0554 significantly. In particular, they won't tell you why the card was not
0555 found unless you turn on the D_INIT_REASONS debugging flag.
0556
0557 Once the driver is running, you can run the arcdump shell script (available
0558 from me or in the full ARCnet package, if you have it) as root to list the
0559 contents of the arcnet buffers at any time. To make any sense at all out of
0560 this, you should grab the pertinent RFCs. (some are listed near the top of
0561 arcnet.c). arcdump assumes your card is at 0xD0000. If it isn't, edit the
0562 script.
0563
0564 Buffers 0 and 1 are used for receiving, and Buffers 2 and 3 are for sending.
0565 Ping-pong buffers are implemented both ways.
0566
0567 If your debug level includes D_DURING and you did NOT define SLOW_XMIT_COPY,
0568 the buffers are cleared to a constant value of 0x42 every time the card is
0569 reset (which should only happen when you do an ifconfig up, or when Linux
0570 decides that the driver is broken). During a transmit, unused parts of the
0571 buffer will be cleared to 0x42 as well. This is to make it easier to figure
0572 out which bytes are being used by a packet.
0573
0574 You can change the debug level without recompiling the kernel by typing::
0575
0576 ifconfig arc0 down metric 1xxx
0577 /etc/rc.d/rc.inet1
0578
0579 where "xxx" is the debug level you want. For example, "metric 1015" would put
0580 you at debug level 15. Debug level 7 is currently the default.
0581
0582 Note that the debug level is (starting with v1.90 ALPHA) a binary
0583 combination of different debug flags; so debug level 7 is really 1+2+4 or
0584 D_NORMAL+D_EXTRA+D_INIT. To include D_DURING, you would add 16 to this,
0585 resulting in debug level 23.
0586
0587 If you don't understand that, you probably don't want to know anyway.
0588 E-mail me about your problem.
0589
0590
0591 I want to send money: what now?
0592 -------------------------------
0593
0594 Go take a nap or something. You'll feel better in the morning.
