From owner-freebsd-net@FreeBSD.ORG  Sun Sep 26 09:36:47 2004
Return-Path: <owner-freebsd-net@FreeBSD.ORG>
Delivered-To: freebsd-net@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 2CD7916A4CE
	for <freebsd-net@FreeBSD.ORG>; Sun, 26 Sep 2004 09:36:47 +0000 (GMT)
Received: from mail-svr1.cs.utah.edu (brahma.cs.utah.edu [155.98.64.200])
	by mx1.FreeBSD.org (Postfix) with ESMTP id E55A843D1D
	for <freebsd-net@FreeBSD.ORG>; Sun, 26 Sep 2004 09:36:46 +0000 (GMT)
	(envelope-from vaibhave@cs.utah.edu)
Received: from faith.cs.utah.edu (faith.cs.utah.edu [155.98.65.40])
	by mail-svr1.cs.utah.edu (Postfix) with ESMTP id 493CF346F1
	for <freebsd-net@FreeBSD.ORG>; Sun, 26 Sep 2004 03:36:40 -0600 (MDT)
Received: by faith.cs.utah.edu (Postfix, from userid 4969)
	id 44B2F2EC21; Sun, 26 Sep 2004 03:36:38 -0600 (MDT)
Received: from localhost (localhost [127.0.0.1])
	by faith.cs.utah.edu (Postfix) with ESMTP id BD51534406
	for <freebsd-net@FreeBSD.ORG>; Sun, 26 Sep 2004 09:36:38 +0000 (UTC)
Date: Sun, 26 Sep 2004 03:36:38 -0600 (MDT)
From: Vaibhave Agarwal <vaibhave@cs.utah.edu>
To: freebsd-net@FreeBSD.ORG
In-Reply-To: <200205080916.g489GDec019355@cairo.anu.edu.au>
Message-ID: <Pine.GSO.4.50L0.0409260327070.20904-100000@faith.cs.utah.edu>
References: <200205080916.g489GDec019355@cairo.anu.edu.au>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Subject: configure Intel 82559 Ethernet card for "Early Interrupts"
X-BeenThere: freebsd-net@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-net>
List-Post: <mailto:freebsd-net@freebsd.org>
List-Help: <mailto:freebsd-net-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 26 Sep 2004 09:36:47 -0000

hi all

I am trying to configure Intel 82559 10/100 Mbps Ethernet card to generate
"Early Interrupts", so that I can receive interrupts from the driver, long
before the whole packet is transferred to the host memory.

I have set the Early Receive Interrupt field in the CSR register of the
card. But still I am not getting these interrupts.

The reason I found out was that the card generates interrupt if the
ethernet header's type/length field is set to 0-1500 value i.e. set
to length of  the packet. But if it is set to Type field ( 0x800 for ip
packet) then  according to the Intel's manual , the interrupt is generated
only if "the  device is configured to generate early interrupts on IP
frames"

Do anybody know how can I configure the device to generate early
interrupts  for IP frames OR any other way to get around with this
problem??

thanks
vaibhave