From owner-freebsd-current@FreeBSD.ORG  Fri Apr 12 13:20:47 2013
Return-Path: <owner-freebsd-current@FreeBSD.ORG>
Delivered-To: freebsd-current@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by hub.freebsd.org (Postfix) with ESMTP id BB15ADC9;
 Fri, 12 Apr 2013 13:20:47 +0000 (UTC)
 (envelope-from phk@phk.freebsd.dk)
Received: from phk.freebsd.dk (phk.freebsd.dk [130.225.244.222])
 by mx1.freebsd.org (Postfix) with ESMTP id 819EF7CB;
 Fri, 12 Apr 2013 13:20:47 +0000 (UTC)
Received: from critter.freebsd.dk (critter.freebsd.dk [192.168.61.3])
 by phk.freebsd.dk (Postfix) with ESMTP id 4BBD089FC1;
 Fri, 12 Apr 2013 13:20:46 +0000 (UTC)
Received: from critter.freebsd.dk (localhost [127.0.0.1])
 by critter.freebsd.dk (8.14.6/8.14.6) with ESMTP id r3CDKjW6005177;
 Fri, 12 Apr 2013 13:20:45 GMT (envelope-from phk@phk.freebsd.dk)
To: lev@FreeBSD.org
Subject: Re: Intel D2500CC motherboard and strange RS232/UART behavior
In-reply-to: <98147894.20130412171822@serebryakov.spb.ru>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
References: <229402991.20130407172016@serebryakov.spb.ru>
 <201304101016.57894.jhb@freebsd.org> <20130411070139.GR76354@funkthat.com>
 <201304111050.37055.jhb@freebsd.org> <1449.1365716268@critter.freebsd.dk>
 <98147894.20130412171822@serebryakov.spb.ru>
Content-Type: text/plain; charset=ISO-8859-1
Date: Fri, 12 Apr 2013 13:20:45 +0000
Message-ID: <5176.1365772845@critter.freebsd.dk>
Cc: John-Mark Gurney <jmg@funkthat.com>, freebsd-current@freebsd.org,
 Adrian Chadd <adrian@freebsd.org>
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.14
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
 <freebsd-current.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-current>, 
 <mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-current>,
 <mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 12 Apr 2013 13:20:47 -0000

In message <98147894.20130412171822@serebryakov.spb.ru>, Lev Serebryakov writes
:

> I mean, there is no good way to distinguish between this (hardware)
> implementation and "true" 4 single UART chips, when it is identify
> itself as "generic 16550 UART", 4 times, at 4 I/O addresses.

That is a kernel configuration issue entirely separate from the
question about the hardware being built to allow and support
interrupt sharing in the first place.

Many old ISA cards also were not recognizable and required hint'ing,
for the exact same reason.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.