AX88x90 updates

After focusing so much time on that old Toshiba card, I thought I'd see if I could get something more modern working as well. I've had one card in my bag knocking around in my bag based on the AX88790 chip. This is the corega FEther II-PXD. I saw it on sale in Akihabara when I was there a few weeks ago, and this card came from Akihabara a few years ago from a friend in Japan. So I thought I'd try it out.

Well, at first it didn't work too well. The MII code was finding gobs of PHYs that were phantoms. This in turned caused bad things to happen when dhclient(8) was run.

There turned out to be three root causes. First, the mii bit-bang code was wrong for reads, yielding bad register reads. Second, the AX88790 has an odd quirk for talking to its internal PHY, so more code was needed to cope with that. Third, the reset code for the NE2000 was also causing problems, so I rewrote it to be AX88x90 reset code. Finally, the internal phy for the AX88790 has a few quirks in silicon that need software workarounds.

Once I'd corrected these problems, the card started working again. Since most of this data is readily available on the net (the asix web site has datasheets for these parts), I'll skip over all the blow-by-blow details. I hopefully had enough comments in the code for people to follow along, as well as the datasheet should make what I've done easy to see.

Now, the arduous task of testing all the AX88x90 cards in my collections... The target card now works correctly, and I believe all of the ones in my collection will work too. Maybe I'll get to the point were all my ed-based PC Cards in my collection will work (except for the Mitsubushi B8895 which I've given up on, and the ones I don't have proper dongles for).

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