From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11855 invoked by alias); 7 Nov 2003 21:14:13 -0000 Mailing-List: contact ecos-discuss-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@sources.redhat.com Received: (qmail 11848 invoked from network); 7 Nov 2003 21:14:12 -0000 Received: from unknown (HELO hermes.chez-thomas.org) (63.225.98.241) by sources.redhat.com with SMTP; 7 Nov 2003 21:14:12 -0000 Received: by hermes.chez-thomas.org (Postfix, from userid 2000) id EBE3350D945; Fri, 7 Nov 2003 14:14:11 -0700 (MST) Received: from localhost (localhost.localdomain [127.0.0.1]) by hermes.chez-thomas.org (Postfix) with ESMTP id 2748350D8E9; Fri, 7 Nov 2003 14:14:10 -0700 (MST) From: Gary Thomas To: Aaron Case Cc: Ecos-Discuss In-Reply-To: References: Content-Type: text/plain Organization: MLB Associates Message-Id: <1068239649.6577.49.camel@hermes> Mime-Version: 1.0 Date: Fri, 07 Nov 2003 21:14:00 -0000 Content-Transfer-Encoding: 7bit X-Spam-Status: No, hits=-4.4 required=5.0 tests=AWL,EMAIL_ATTRIBUTION,IN_REP_TO,QUOTED_EMAIL_TEXT, REFERENCES,REPLY_WITH_QUOTES,USER_AGENT_XIMIAN autolearn=ham version=2.55 X-Spam-Level: X-Spam-Checker-Version: SpamAssassin 2.55 (1.174.2.19-2003-05-19-exp) Subject: Re: [ECOS] EDB7312(ARM720T) interrupts X-SW-Source: 2003-11/txt/msg00096.txt.bz2 On Fri, 2003-11-07 at 14:01, Aaron Case wrote: > Hello, > > I have a question about implementing interrupts with the rich eCos interrupt > API with the limited ARM interrupt vector table. > > >From my experience, and as mentioned in the Massa test, the ARM architecture > has only two vectors for interrupts(FIQ and IRQ) and the eCos API is > implemented more readily for architectures that have multiple entries in > their vector tables. > > It is therefore up to the software to look at the INTSR1/2/3 registers to > determine the source of the interrupt. > > So when I create my 23 different interrupts, where is the most advisable > place to decode the source of the interrupt. Ive considered having all the > IRQ's share an ISR and each have a unique DSR identifiable through the data > argument of the cyg_interrupt_create() call. > > Having all the interrupts share an ISR to decode the interrupt source SEEMS > to be more processing than the ISR was intended to handle. > > If the aforementioned approach is not in vogue(or feasible), than could > someone out there who has done this before and would be able to point me to > a post or document that describes how to approach this implementation best. > On the ARM architecture, we assume that your HAL has a function "hal_IRQ_handler()" which will interrogate your hardware and return a unique value (typically 1..N) indicating which of those interrupts has just occurred. Then there can be a potentially different ISR for each interrupt. Look at some of the ARM HALs to see how this is done. -- Gary Thomas MLB Associates -- Before posting, please read the FAQ: http://sources.redhat.com/fom/ecos and search the list archive: http://sources.redhat.com/ml/ecos-discuss