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From: Terry Lambert <terry@lambert.org>
Message-Id: <199605062329.QAA22177@phaeton.artisoft.com>
Subject: Re: shared interrupts?
To: hasty@rah.star-gate.com (Amancio Hasty Jr.)
Date: Mon, 6 May 1996 16:29:14 -0700 (MST)
Cc: terry@lambert.org, freebsd-hackers@FreeBSD.ORG
In-Reply-To: <199605062302.QAA00292@rah.star-gate.com> from "Amancio Hasty Jr." at May 6, 96 04:02:52 pm
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> > > Is it possible for PCI devices to shared interrupts?
> > 
> > Yes.
> > 
> > > And if so how does one identify which device is generating the interrupt?
> > 
> > One asks each device sharing the interrupt "Are *yo* talking to *me*?".
> > 
> > 8-).
> 
> Okay, specifically how does one ask each device "Are you really talking
> to me?"

You need to ask Stephan -- my copy of the PCI spec is at home.  8-(.

I believe PCI requires a status register.

The default PCI code already does this because Intel OEM products
division motherboards like to throw everything onto the same interrupt
by default (Plato, Zeus, et al).


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.