I am trying to get a CardBus ethernet card woking.

My old laptop (Compaq Presario 1600) has Texas Instruments
PCI-1211 CardBus bridge. I have added its DID/VID pair to
variant[] array in /sys/src/9/pc/pccard.c:64 and recompiled 9pcf
kernel. Now I see in /dev/kmesg;

#Y0: TI PCI-1211 Cardbus Controller, 03800000 intl 9

and, under #Y, a cb0ctl file. So far, so good. (is it not? How do
I make sure it's really OK?)

Now, with a 3com 3CCFE575BT ethernet card inserted, kmesg
says

#Y0: TI PCI-1211 Cardbus Controller, 03800000 intl 9
PCI.32.0.0 mem[1] 03c00080 128
PCI.32.0.0 mem[2] 03c00000 128
tcm59Xpci: port 0xFFFFFFFF in use

Oh no, ioalloc() in /sys/src/9/etherelnk.c:1472 is failing? I see
no /net/ether bound.

I poke around a bit:

I've just run into something similar with a Netgear GA511, which is
actually a Realtek 8169, and a Ricoh Cardbus bridge. The cardbus code
allocates ports from 0x400 to 0x5ff with ioreserve() and then the
ethernet driver can't allocate ports at 0x400 with ioalloc(). jmk may
have a fix for this.