Subject: q: ethernet phy resets
To: None <tech-net@netbsd.org>
From: David Young <dyoung@pobox.com>
List: tech-net
Date: 12/30/2007 22:20:30
What are drivers such as nfe(4) trying to accomplish by resetting all
PHYs when there is a change of media settings?
Just for example, nfe_ifmedia_upd(),

        struct mii_softc *miisc;

        if (mii->mii_instance != 0) {
                LIST_FOREACH(miisc, &mii->mii_phys, mii_list)
                        mii_phy_reset(miisc);
        }

This seems to get under the MII/PHY abstraction a bit.  Also, by my
reading of mii_mediachg() and drivers such as ukphy(4), either the MII
framework or a PHY driver resets the PHY whenever that is necessary.

I suspect that code such as the above appears more than once in the tree
because it was copied and pasted several times from some other ethernet
driver, not because it is necessary.  Is there something I am missing?

Dave

-- 
David Young             OJC Technologies
dyoung@ojctech.com      Urbana, IL * (217) 278-3933 ext 24