Subject: Re: Setting the default port on ethernet cards
To: Chris G. Demetriou <cgd@cs.cmu.edu>
From: Jonathan Stone <jonathan@DSG.Stanford.EDU>
List: tech-net
Date: 04/23/1997 17:37:47
> Are there any cards other than the 3c59x's that set up their ASIC
> based on EEPROM contents at powerup time?


>I'm pretty sure that the SMC/WD ISA boards (at least some models) do
>as well.

I agree, but with all due respect, that's not the point.  Eric's point
is that if a 3c595 comes up in 10Mbit mode on a 100Mbit segment, it
will wedge the entire 100Mbit segment (at least until it gets
ifconfig'ed to 100Mbit mode).  That be due to 100mbit hubs backing
down all their ports to 10Mbits when they see a 10Mbit card.  Either
way, the 100Mbit cards without autosense are then screwed until the
10Mbit card is reconfigured.

That's something that *should* be fixed.  Other 10/100 cards supported
by NetBSD don't seem to have this particular problem, because they can
do NWay autosense in hardware, and/or don't automatically go on the
air at powerup time.

I wasn't aware of any 10/100Mbit SMC/WD isa cards.  Booting an SMC
card with the wrong media just means the card is talking to thin air,
rather than wedging an entire segment.



>You _can_ simly leave the interface alone and let ifconfig do the
>right thing, but that doesn't necessarily help for:
>
>        (1) netbooting,

Yes. I wanted to make this point too.  But we might reasonably assume
someone going to the trouble of burning an inserting bootPROMs can set
the default media type with the vendor utilities.  Personally, I don't
think 100Mbit should be anywhere near that painful.

The issue of needing to get the media type right without OS
intervention seems the same, though.



>        (2) the case where you want to reboot into DOS, and have the
>           card/packet driver use the right port automatically.

Huh? If you're already dual-booting to DOS, then the marginal cost of
setting set the oncard NVRAM to the desired port with the vendor's DOS
utility is very low.  Just fix it next time you're in DOS.  Yes,
that's inelegant, but not exactly unlivable-with.

And, as above, leaving the interface alone till ifconfig fixes it,
isn't really a viable option for some cards and media.  The vendor DOS
utility is required. Ugh. I'd like to see *BSD make that unecessary,
but it is more urgent on some cards than on others.