As you might have read on other pages on this server, I am a collector of old computers with Microchannel bus, like the PS/2 series made by IBM. A few months ago, I was given a stack of SKNET Junior Ethernet cards and even a PS/2 Model 80-311 with three SKNET MC2 boards :-)
However, I prefer to run Linux on my PS/2's, and didn't find a Linux driver for them. The nearest one I found was a driver for the SK_G16, which is quite similar in its structure to the microchannel variants, however the driver is relatively old (last modification in 1994) and not loadable as a module, therefore not allowing to control more than one board. So I decided to write a new driver from scratch. Here is the result:
You may download the sources here. The driver was developed with kernel version 2.0.35 and tested on a couple of PS/2 machines, both linked statically into the kernel and loaded as a module. Supported boards are the SKNET junior MC2 and the SKNET MC2(+). The current version is confirmed to run with 2.2 kernels (in fact it has become part of the Linux kernel distribution with 2.2.10) and with the experimental 2.3.46 kernel. Configurations with more than one card were tested with up to three boards. Mixing cards of both types should work also, though I haven't tested this. Interrupt sharing should work, but I didn't have a machine full enough that the configuration program would have needed to assign an interrupt to more than one board.
The driver is GPL, so you are free to use and improve it, but like always, it comes without any warranty: If you smash something with it, you're the proud owner of all remaining chunks ;-)
Apart from the driver sources themselves, you will find a patch file to modify some other files in the Linux kernel tree. This way, the driver will show up as a configuration option just like all other network drivers. The patches are relative to a 2.0.35 source tree patched with the MCA patches available on www.dgmicro.com.
A big thank you to SK for their quick and competent support; within half an hour after sending my request for documentation I had all documents I needed, including sample programs!