Re: kern/44630: rgephy(4) likes auto-negotiation too much

[River Tarnell <r.tarnell%IEEE.ORG@localhost>]

The following reply was made to PR kern/44630; it has been noted by GNATS.

From: River Tarnell <r.tarnell%IEEE.ORG@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%NetBSD.org@localhost, gnats-admin%NetBSD.org@localhost,
        netbsd-bugs%NetBSD.org@localhost
Subject: Re: kern/44630: rgephy(4) likes auto-negotiation too much
Date: Thu, 24 Feb 2011 08:00:34 +0000

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 David Laight:
 >  > rgephy(4) enables auto-negotiation even when the user explicitly
 >  > specifies a media type.  This is unfortunate, because if the switch is
 >  > forced to 100-FD, the card will fail to negotiate and fall back to
 >  > 100-HD.  The duplex mismatch makes it so slow as to be unusable.
   
 >  Does setting the PHYs autonegotiate advertise register (ANAR)
 >  to the required mode help?
 
 Isn't this already done when 'ifconfig re0 media 100basetx' is 
 specified?
 
                 case IFM_100_TX:
                         speed = RGEPHY_S100;
                         anar |= RGEPHY_ANAR_TX_FD | RGEPHY_ANAR_TX;
 
 ANAR_TX is later removed by 'mediaopt full-duplex':
 
                         if ((ife->ifm_media & IFM_GMASK) == IFM_FDX) {
                                 speed |= RGEPHY_BMCR_FDX;
                                 gig = RGEPHY_1000CTL_AFD;
                                 anar &= ~(RGEPHY_ANAR_TX | RGEPHY_ANAR_10);
 
 ... which leaves anar = RGEPHY_ANAR_TX_FD (100Base-TX).
 
 >  IMHO that should be done instead of forcing the actual mode.
 
 In this particular case I believe this is the right solution, because 
 the switch is forced to 100-FD, i.e. auto-negotiation is disabled.
 
        - river.
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