From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261742AbUB0JGF (ORCPT ); Fri, 27 Feb 2004 04:06:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261746AbUB0JGF (ORCPT ); Fri, 27 Feb 2004 04:06:05 -0500 Received: from caramon.arm.linux.org.uk ([212.18.232.186]:34569 "EHLO caramon.arm.linux.org.uk") by vger.kernel.org with ESMTP id S261742AbUB0JGA (ORCPT ); Fri, 27 Feb 2004 04:06:00 -0500 Date: Fri, 27 Feb 2004 09:05:48 +0000 From: Russell King To: Michael Frank Cc: Benjamin Herrenschmidt , "Grover, Andrew" , Mark Gross , arjanv@redhat.com, Tim Bird , root@chaos.analogic.com, Linux Kernel list Subject: Re: Why no interrupt priorities? Message-ID: <20040227090548.A15644@flint.arm.linux.org.uk> Mail-Followup-To: Michael Frank , Benjamin Herrenschmidt , "Grover, Andrew" , Mark Gross , arjanv@redhat.com, Tim Bird , root@chaos.analogic.com, Linux Kernel list References: <1077859968.22213.163.camel@gaston> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: ; from mhf@linuxmail.org on Fri, Feb 27, 2004 at 02:26:31PM +0800 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 27, 2004 at 02:26:31PM +0800, Michael Frank wrote: > Is this to imply that edge triggered shared interrupts are used anywhere? It is (or used to be) rather common with serial ports. Remember that COM1 and COM3 were both defined to use IRQ4 and COM2 and COM4 to use IRQ3. > Never occured to me to use shared IRQ's edge triggered as this mode > _cannot_ work reliably for HW limitations. The serial driver takes great care with this - when we service such an interrupt, we keep going until we have scanned all the devices until such time that we can say "all devices are no longer signalling an interrupt". This is something it has always done - it's nothing new. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 PCMCIA - http://pcmcia.arm.linux.org.uk/ 2.6 Serial core