[9fans] Am97c960 etc.

[Lucio De Re <lucio@proxima.alt.za>]

First of all, hearty thanks to forsyth for his help getting a device
driver going for the PCnet-ISA controller.

I have only played with the boot/pc version, and I only know that it
initialises without panic, but I'm a lot more confident of being able
to use it now.

I did go to a lot of trouble to make "etherpcnet.c" as general as
possible, but I can only test it for the 97c960 as I have no access to
any other controller (I suppose I can try the VMware emulation, but
that strikes me as asking for trouble).  If anyone is interested, I'll
clean up the code a bit and then post the driver on my web site.

I really would like some review (it's a merge of a driver from forsyth
and the release version) before I tackle the 9/pc alternative and then
have to duplicate all the error corrections :-)  Mail me if you'd
prefer a copy by e-mail.

One item I have not understood at all in my quest for information is
Plan 9's use of bounce buffers when using DMA in a 24-bit environment.
Could someone familiar with this topic point me to the pertinent
information or source code?

++L