From owner-freebsd-hackers Tue Sep 12 05:36:10 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.freebsd.org (8.6.12/8.6.6) id FAA04427 for hackers-outgoing; Tue, 12 Sep 1995 05:36:10 -0700 Received: from kryten.atinc.com (kryten.Atinc.COM [198.138.38.7]) by freefall.freebsd.org (8.6.12/8.6.6) with ESMTP id FAA04420 for ; Tue, 12 Sep 1995 05:36:07 -0700 Received: (jmb@localhost) by kryten.atinc.com (8.6.9/8.3) id IAA09405; Tue, 12 Sep 1995 08:28:39 -0400 Date: Tue, 12 Sep 1995 08:28:34 -0400 (EDT) From: "Jonathan M. Bresler" Subject: Re: Help! :-( (fwd) To: Joe Greco cc: "Jordan K. Hubbard" , gibbs@freefall.freebsd.org, hackers@freebsd.org In-Reply-To: <199509120403.XAA18652@brasil.moneng.mei.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: hackers-owner@freebsd.org Precedence: bulk On Mon, 11 Sep 1995, Joe Greco wrote: > > Can you explain a little more about this system? What's in the thing? > > I've never seen one of these: > > chip2 rev 2 on pci0:11 > > Before! :-) you can get details from the book _pci_system_architecture_ by tom shanley and don anderson, addison-wesley. look at the chapter on "pci device configuration". as i understand it, a pci-pci bridge connects two pci busses in a heirarchical topology (2 host-pci bridges can be used to form a peer relationship). > As it's been explained to me, that is a PCI to PCI bridge ("PPB"), which > "connects" two PCI busses together, or somesuch. It's a gateway onto a > different bus. Apparently certain PCI peripherals, such as 4-way Ethernet > cards, like to glue 4 PCI controllers together on a bus and then provide a > single gateway onto the system's PCI bus. In this case, the AHA3940 > apparently puts two controllers behind a PPB. I'm mostly familiar with bus > bridges in other contexts, so I am not sure that my description is totally > correct, and I have no idea what the issues all are. > > I'll be the first to admit that PCI puzzles me. I'm not really a PC > hardware guy - I leave that to the geniuses like Rod. Speaking of Rod, he > was the one who sold execpc.com the motherboard and PCI Ethernet cards in > question. > > Thanks, > > ... Joe > > ------------------------------------------------------------------------------- > Joe Greco - Systems Administrator jgreco@ns.sol.net > Solaria Public Access UNIX - Milwaukee, WI 414/342-4847 > Jonathan M. Bresler jmb@kryten.atinc.com | Analysis & Technology, Inc. FreeBSD Postmaster jmb@FreeBSD.Org | 2341 Jeff Davis Hwy play go. | Arlington, VA 22202 ride bike. hack FreeBSD.--ah the good life | 703-418-2800 x346