From owner-freebsd-alpha  Mon Jun 24 11: 7:12 2002
Delivered-To: freebsd-alpha@freebsd.org
Received: from beppo.feral.com (beppo.feral.com [192.67.166.79])
	by hub.freebsd.org (Postfix) with ESMTP id C033D37B4B9
	for <alpha@FreeBSD.ORG>; Mon, 24 Jun 2002 11:05:20 -0700 (PDT)
Received: from mailhost.feral.com (mjacob@mailhost.feral.com [192.67.166.1])
	by beppo.feral.com (8.11.3/8.11.3) with ESMTP id g5OI4sO81913;
	Mon, 24 Jun 2002 11:04:54 -0700 (PDT)
	(envelope-from mjacob@feral.com)
Date: Mon, 24 Jun 2002 11:04:53 -0700 (PDT)
From: Matthew Jacob <mjacob@feral.com>
X-Sender: mjacob@beppo
Reply-To: mjacob@feral.com
To: Andrew Gallatin <gallatin@cs.duke.edu>
Cc: "M. Warner Losh" <imp@village.org>, ticso@cicely.de,
	alpha@FreeBSD.ORG
Subject: Re: Wither the nexus driver?
In-Reply-To: <15638.39243.635286.767878@grasshopper.cs.duke.edu>
Message-ID: <Pine.BSF.4.21.0206241101160.94821-100000@beppo>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Sender: owner-freebsd-alpha@FreeBSD.ORG
Precedence: bulk
List-ID: <freebsd-alpha.FreeBSD.ORG>
List-Archive: <http://docs.freebsd.org/mail/> (Web Archive)
List-Help: <mailto:majordomo@FreeBSD.ORG?subject=help> (List Instructions)
List-Subscribe: <mailto:majordomo@FreeBSD.ORG?subject=subscribe%20freebsd-alpha>
List-Unsubscribe: <mailto:majordomo@FreeBSD.ORG?subject=unsubscribe%20freebsd-alpha>
X-Loop: FreeBSD.org


note that on 8X00 and 4100 systems that the PCI chipset is *not* the root
nexus (or shouldn't be)

The 8X00 main system bus is the TLSB (turbolaser), which has different memory,
cpu or I/O modules. The I/O modules KFTIA/KTFTH then send hoses out to
outlying boxes. One of these happens to be a DWLPX (pci controller), but many
others are possible, including FutureBus (which shows you how *long* futurebus
has been rolling around).

The 4100 main system bus has MCbus as the main system bus. It has MCPCIA
modules which are the PCI interfaces.

This is has always been a peeve of mine about *BSD usage of root 'nexus'- the
assumption that the PCI chipset is the one and only nexus.

On Mon, 24 Jun 2002, Andrew Gallatin wrote:

> 
> M. Warner Losh writes:
>  > In message: <20020623233355.GE53233@cicely5.cicely.de>
>  >             Bernd Walter <ticso@cicely5.cicely.de> writes:
>  > : root node is the chipset:
>  > : [67]cicely9# devinfo 
>  > : cia0
>  > 
>  > OK.  Is cia the only chipset, or are there others?
> 
> There are many more.  
> 
> apecs, dwlpx, irongate, lca, mcpcia, t2, tsunami.
> And I'm probably leaving a few out.
> 
> Drew
> 
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-alpha" in the body of the message
> 


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-alpha" in the body of the message