kern/128331: [agp] nForce3-250 AGP not detected correctly

[Manfred Knick]

The following reply was made to PR kern/128331; it has been noted by GNATS.

From: Manfred Knick <manfred.knick at t-online.de>
To: bug-followup at FreeBSD.org, Manfred.Knick at T-Online.de
Cc:  
Subject: Re: kern/128331: [agp] nForce3-250 AGP not detected correctly
Date: Mon, 24 Nov 2008 12:24:25 +0100

 ADDENDUM:
 
 Digging further on, I came across
 
 http://www.ocworkbench.com/2005/uli/m1695/g1.htm
 
 which states:
 <cite>
 M1695 ... Tunnel Chip ... is ... chipset that uses a tunneling technique 
 to interconnect the two "North Bridges" as the South Bridge ...
 </cite> .
 
 Thus, the approach is as follows:
 
 [ CPU ] <-- HyperTransport Link -->  [ M1695 ] <-- HyperTransport Link 
 --> [ nForce3 250 ] <-- AGP Bus --> [ G550 ]
 
 which implies that indeed we have two host bridges, but sequentially - 
 not in parallel.