From owner-freebsd-hackers  Thu Feb 22 05:01:52 1996
Return-Path: owner-hackers
Received: (from root@localhost)
          by freefall.freebsd.org (8.7.3/8.7.3) id FAA15929
          for hackers-outgoing; Thu, 22 Feb 1996 05:01:52 -0800 (PST)
Received: from sun4nl.NL.net (sun4nl.NL.net [193.78.240.1])
          by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id FAA15895
          for <hackers@FreeBSD.org>; Thu, 22 Feb 1996 05:01:44 -0800 (PST)
Received: from spase by sun4nl.NL.net via EUnet
	id AA19238 (5.65b/CWI-3.3); Thu, 22 Feb 1996 14:01:38 +0100
Received: (from root@localhost) by mercurius.spase.nl (8.6.11/8.6.11) id NAA11226 for hackers@FreeBSD.org; Thu, 22 Feb 1996 13:46:39 +0100
Date: Thu, 22 Feb 1996 13:46:39 +0100
From: root <root@spase.nl>
Message-Id: <199602221246.NAA11226@mercurius.spase.nl>
To: hackers@FreeBSD.org
Sender: owner-hackers@FreeBSD.org
Precedence: bulk

>From freefall.freebsd.org!owner-freebsd-hackers  Wed Feb 21 12:42:15 1996 remote from sun4nl
Received: from ra.dkuug.dk by sun4nl.NL.net with SMTP
	id AA14598 (5.65b/CWI-3.3); Wed, 21 Feb 1996 12:42:15 +0100
Received: from freefall.freebsd.org (freefall.FreeBSD.ORG [192.216.222.4]) by ra.dkuug.dk (8.6.12/8.6.12) with ESMTP id MAA05848; Wed, 21 Feb 1996 12:08:09 +0100
Received: from localhost (daemon@localhost)
          by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id BAA20545
          Wed, 21 Feb 1996 01:18:34 -0800 (PST)
Received: (from root@localhost)
          by freefall.freebsd.org (8.7.3/8.7.3) id BAA20530
          for hackers-outgoing; Wed, 21 Feb 1996 01:18:24 -0800 (PST)
Received: from baygull.rtd.com (baygull.rtd.com [198.102.68.5])
          by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id BAA20525
          for <hackers@freebsd.org>; Wed, 21 Feb 1996 01:18:21 -0800 (PST)
Received: (from news@localhost) by baygull.rtd.com (8.6.9/8.6.9.1) id CAA17073; Wed, 21 Feb 1996 02:18:08 -0700
To: hackers@FreeBSD.org
Path: freefall.freebsd.org!owner-freebsd-hackers
From: koshy@india.hp.com (A JOSEPH KOSHY)
Newsgroups: rtd.freebsd.hackers
Subject: ISA device irq/mem auto-configuration
Date: Wed, 21 Feb 1996 12:48:53 +0530
Lines: 25
Message-Id: <199602210718.AA255777134@fakir.india.hp.com>
Nntp-Posting-Host: seagull.rtd.com
Sender: owner-hackers@FreeBSD.org
Precedence: bulk


This is a basic question about how we handle boards whose IRQ, I/O and
memory ranges can be autodetected at boot time.  

Consider a network card : If the kernel has been configured for say, 
IRQ 5 but the actual board was detected at IRQ 11, whats the right thing to 
do? We could :

(a) Ignore the board : this can be pretty frustrating to the user.

(b) Print out some informative message : stating something like 
    "board setup for IRQ XX but kernel was configured for YY" and leave
    it at that.  

(c) Take in the new IRQ setting somehow and do the right thing.

Option (C) seems to me to be the right thing from the users point of
view; I don't know enough of the FreeBSD kernel to tell if it is feasible.

I have seen in some places "-1" being used as a kind of "wildcard" address
in some drivers.  Is this a convention?

Can anyone point me to further reading?   Have I missed something?

Koshy