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+ Originally, this driver was written for the Digital Equipment
+ Corporation series of EtherWORKS Ethernet cards:
+ DE434 TP 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:
+ 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:
+ 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
+ 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.