From owner-freebsd-hackers@FreeBSD.ORG Mon Apr 10 02:47:56 2006 Return-Path: X-Original-To: hackers@freebsd.org Delivered-To: freebsd-hackers@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1B87116A400 for ; Mon, 10 Apr 2006 02:47:56 +0000 (UTC) (envelope-from mwm-keyword-freebsdhackers.102a7e@mired.org) Received: from mired.org (dsl092-153-074.wdc2.dsl.speakeasy.net [66.92.153.74]) by mx1.FreeBSD.org (Postfix) with SMTP id 4BBE243D45 for ; Mon, 10 Apr 2006 02:47:54 +0000 (GMT) (envelope-from mwm-keyword-freebsdhackers.102a7e@mired.org) Received: (qmail 10737 invoked by uid 1001); 10 Apr 2006 02:47:54 -0000 Received: by localhost.mired.org (tmda-sendmail, from uid 1001); Sun, 09 Apr 2006 22:47:53 -0400 (EDT) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <17465.51033.78362.699332@bhuda.mired.org> Date: Sun, 9 Apr 2006 22:47:53 -0400 To: "M. Warner Losh" In-Reply-To: <20060409.185335.105395062.imp@bsdimp.com> References: <9399827.1657341144611794358.JavaMail.root@vms070.mailsrvcs.net> <17465.32905.727289.260996@bhuda.mired.org> <20060409.185335.105395062.imp@bsdimp.com> X-Mailer: VM 7.17 under 21.4 (patch 19) "Constant Variable" XEmacs Lucid X-Primary-Address: mwm@mired.org X-face: "5Mnwy%?j>IIV\)A=):rjWL~NB2aH[}Yq8Z=u~vJ`"(,&SiLvbbz2W`; h9L,Yg`+vb1>RG% *h+%X^n0EZd>TM8_IB;a8F?(Fb"lw'IgCoyM.[Lg#r\ X-Delivery-Agent: TMDA/1.0.3 (Seattle Slew) From: Mike Meyer Cc: hackers@freebsd.org, babkin@users.sourceforge.net, ceri@submonkey.net, scottl@samsco.org Subject: Re: What's in a (device) name? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 Apr 2006 02:47:56 -0000 In <20060409.185335.105395062.imp@bsdimp.com>, M. Warner Losh typed: > In message: <17465.32905.727289.260996@bhuda.mired.org> > Mike Meyer writes: > : The major problem with it is that todays bus architectures don't have > : stable device addresses. Instead of devices having a fixed address on > : the bus that the user sets, the addresses are assigned as the devices > : are discovered. This is pretty much a requirement if you want to sell > : hardware to 12:00 flashers. While that's not the market that FreeBSD > : deals with, it is the hardware that FreeBSD runs on. > usb assigns addresses dynamically. Everyone else does it basically > statically. PCI slot/device numbers are static, but extreme > configurations can change the bus number. USB is popular enough and PCI changes enough that we have to be able to deal with them. Firewire would seem to be a lot like USB - hot pluggable and chainable, though I'm not sure if something like a firewire hub. What does it to do wire down device addresses? Thanks, http://www.mired.org/consulting.html Independent Network/Unix/Perforce consultant, email for more information.