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Diffstat (limited to 'kernel/Documentation/networking/de4x5.txt')
| -rw-r--r-- | kernel/Documentation/networking/de4x5.txt | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/kernel/Documentation/networking/de4x5.txt b/kernel/Documentation/networking/de4x5.txt new file mode 100644 index 000000000..c8e4ca9b2 --- /dev/null +++ b/kernel/Documentation/networking/de4x5.txt @@ -0,0 +1,178 @@ + Originally, this driver was written for the Digital Equipment + Corporation series of EtherWORKS Ethernet cards: + + DE425 TP/COAX EISA + DE434 TP PCI + DE435 TP/COAX/AUI PCI + DE450 TP/COAX/AUI PCI + DE500 10/100 PCI Fasternet + + but it will now attempt to support all cards which conform to the + Digital Semiconductor SROM Specification. The driver currently + recognises the following chips: + + DC21040 (no SROM) + DC21041[A] + DC21140[A] + DC21142 + DC21143 + + So far the driver is known to work with the following cards: + + KINGSTON + Linksys + ZNYX342 + SMC8432 + SMC9332 (w/new SROM) + ZNYX31[45] + ZNYX346 10/100 4 port (can act as a 10/100 bridge!) + + The driver has been tested on a relatively busy network using the DE425, + DE434, DE435 and DE500 cards and benchmarked with 'ttcp': it transferred + 16M of data to a DECstation 5000/200 as follows: + + TCP UDP + TX RX TX RX + DE425 1030k 997k 1170k 1128k + DE434 1063k 995k 1170k 1125k + DE435 1063k 995k 1170k 1125k + DE500 1063k 998k 1170k 1125k in 10Mb/s mode + + All values are typical (in kBytes/sec) from a sample of 4 for each + measurement. Their error is +/-20k on a quiet (private) network and also + depend on what load the CPU has. + + ========================================================================= + + The ability to load this driver as a loadable module has been included + and used extensively during the driver development (to save those long + reboot sequences). Loadable module support under PCI and EISA has been + achieved by letting the driver autoprobe as if it were compiled into the + kernel. Do make sure you're not sharing interrupts with anything that + cannot accommodate interrupt sharing! + + To utilise this ability, you have to do 8 things: + + 0) have a copy of the loadable modules code installed on your system. + 1) copy de4x5.c from the /linux/drivers/net directory to your favourite + temporary directory. + 2) for fixed autoprobes (not recommended), edit the source code near + line 5594 to reflect the I/O address you're using, or assign these when + loading by: + + insmod de4x5 io=0xghh where g = bus number + hh = device number + + NB: autoprobing for modules is now supported by default. You may just + use: + + insmod de4x5 + + to load all available boards. For a specific board, still use + the 'io=?' above. + 3) compile de4x5.c, but include -DMODULE in the command line to ensure + that the correct bits are compiled (see end of source code). + 4) if you are wanting to add a new card, goto 5. Otherwise, recompile a + kernel with the de4x5 configuration turned off and reboot. + 5) insmod de4x5 [io=0xghh] + 6) run the net startup bits for your new eth?? interface(s) manually + (usually /etc/rc.inet[12] at boot time). + 7) enjoy! + + To unload a module, turn off the associated interface(s) + 'ifconfig eth?? down' then 'rmmod de4x5'. + + Automedia detection is included so that in principle you can disconnect + from, e.g. TP, reconnect to BNC and things will still work (after a + pause whilst the driver figures out where its media went). My tests + using ping showed that it appears to work.... + + By default, the driver will now autodetect any DECchip based card. + Should you have a need to restrict the driver to DIGITAL only cards, you + can compile with a DEC_ONLY define, or if loading as a module, use the + 'dec_only=1' parameter. + + I've changed the timing routines to use the kernel timer and scheduling + functions so that the hangs and other assorted problems that occurred + while autosensing the media should be gone. A bonus for the DC21040 + auto media sense algorithm is that it can now use one that is more in + line with the rest (the DC21040 chip doesn't have a hardware timer). + The downside is the 1 'jiffies' (10ms) resolution. + + IEEE 802.3u MII interface code has been added in anticipation that some + products may use it in the future. + + The SMC9332 card has a non-compliant SROM which needs fixing - I have + patched this driver to detect it because the SROM format used complies + to a previous DEC-STD format. + + I have removed the buffer copies needed for receive on Intels. I cannot + remove them for Alphas since the Tulip hardware only does longword + aligned DMA transfers and the Alphas get alignment traps with non + longword aligned data copies (which makes them really slow). No comment. + + I have added SROM decoding routines to make this driver work with any + card that supports the Digital Semiconductor SROM spec. This will help + all cards running the dc2114x series chips in particular. Cards using + the dc2104x chips should run correctly with the basic driver. I'm in + debt to <mjacob@feral.com> for the testing and feedback that helped get + this feature working. So far we have tested KINGSTON, SMC8432, SMC9332 + (with the latest SROM complying with the SROM spec V3: their first was + broken), ZNYX342 and LinkSys. ZNYX314 (dual 21041 MAC) and ZNYX 315 + (quad 21041 MAC) cards also appear to work despite their incorrectly + wired IRQs. + + I have added a temporary fix for interrupt problems when some SCSI cards + share the same interrupt as the DECchip based cards. The problem occurs + because the SCSI card wants to grab the interrupt as a fast interrupt + (runs the service routine with interrupts turned off) vs. this card + which really needs to run the service routine with interrupts turned on. + This driver will now add the interrupt service routine as a fast + interrupt if it is bounced from the slow interrupt. THIS IS NOT A + RECOMMENDED WAY TO RUN THE DRIVER and has been done for a limited time + until people sort out their compatibility issues and the kernel + interrupt service code is fixed. YOU SHOULD SEPARATE OUT THE FAST + INTERRUPT CARDS FROM THE SLOW INTERRUPT CARDS to ensure that they do not + run on the same interrupt. PCMCIA/CardBus is another can of worms... + + Finally, I think I have really fixed the module loading problem with + more than one DECchip based card. As a side effect, I don't mess with + the device structure any more which means that if more than 1 card in + 2.0.x is installed (4 in 2.1.x), the user will have to edit + linux/drivers/net/Space.c to make room for them. Hence, module loading + is the preferred way to use this driver, since it doesn't have this + limitation. + + Where SROM media detection is used and full duplex is specified in the + SROM, the feature is ignored unless lp->params.fdx is set at compile + time OR during a module load (insmod de4x5 args='eth??:fdx' [see + below]). This is because there is no way to automatically detect full + duplex links except through autonegotiation. When I include the + autonegotiation feature in the SROM autoconf code, this detection will + occur automatically for that case. + + Command line arguments are now allowed, similar to passing arguments + through LILO. This will allow a per adapter board set up of full duplex + and media. The only lexical constraints are: the board name (dev->name) + appears in the list before its parameters. The list of parameters ends + either at the end of the parameter list or with another board name. The + following parameters are allowed: + + fdx for full duplex + autosense to set the media/speed; with the following + sub-parameters: + TP, TP_NW, BNC, AUI, BNC_AUI, 100Mb, 10Mb, AUTO + + Case sensitivity is important for the sub-parameters. They *must* be + upper case. Examples: + + insmod de4x5 args='eth1:fdx autosense=BNC eth0:autosense=100Mb'. + + For a compiled in driver, in linux/drivers/net/CONFIG, place e.g. + DE4X5_OPTS = -DDE4X5_PARM='"eth0:fdx autosense=AUI eth2:autosense=TP"' + + Yes, I know full duplex isn't permissible on BNC or AUI; they're just + examples. By default, full duplex is turned off and AUTO is the default + autosense setting. In reality, I expect only the full duplex option to + be used. Note the use of single quotes in the two examples above and the + lack of commas to separate items. |