From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20701 invoked by alias); 2 Apr 2008 19:40:34 -0000 Received: (qmail 20691 invoked by uid 22791); 2 Apr 2008 19:40:33 -0000 X-Spam-Check-By: sourceware.org Received: from main.gmane.org (HELO ciao.gmane.org) (80.91.229.2) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 02 Apr 2008 19:40:05 +0000 Received: from root by ciao.gmane.org with local (Exim 4.43) id 1Jh8oV-0006ZX-5h for ecos-discuss@sources.redhat.com; Wed, 02 Apr 2008 19:40:03 +0000 Received: from c-76-17-159-23.hsd1.mn.comcast.net ([76.17.159.23]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 02 Apr 2008 19:40:03 +0000 Received: from grante by c-76-17-159-23.hsd1.mn.comcast.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 02 Apr 2008 19:40:03 +0000 To: ecos-discuss@sources.redhat.com From: Grant Edwards Date: Wed, 02 Apr 2008 19:40:00 -0000 Message-ID: References: <200804022125.19510.neundorf@kde.org> <20080402193008.GE7929@lunn.ch> User-Agent: slrn/0.9.8.1pl1 (Linux) X-IsSubscribed: yes Mailing-List: contact ecos-discuss-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: ecos-discuss-owner@ecos.sourceware.org Subject: [ECOS] Re: On ARM7 can one of FIQ/IRQ be used for non-eCos stuff? X-SW-Source: 2008-04/txt/msg00024.txt.bz2 On 2008-04-02, Andrew Lunn wrote: >> Yes. I think providing an official way how to use the FIQ with >> lowest possible overhead under eCos would be good. Some kind >> of communication with eCos is required I think, e.g. a >> recommended way how to generate a regular interrupt so that if >> some condition is detected in the FIQ handler a regular ISR >> can overtake. > > I've done this before, but it used hardware support. > > The Intel StrongARM interrupt controller had a bit you could > set to cause an IRQ interrupt to happen. So in the FIQ you hit > this bit and exit the FIQ. Once interrupts are re-enabled the > IRQ goes off and you are in normal eCos interrupt context. How did eCos know where the interrupt came from? Did that bit you set have it's own unique hardware-generated ID value? > I don't know of a generic way to do this. There is no > standardised interrupt controller for ARMs. I think it's going to be target-dependent. -- Grant Edwards grante Yow! I'll eat ANYTHING at that's BRIGHT BLUE!! visi.com -- Before posting, please read the FAQ: http://ecos.sourceware.org/fom/ecos and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss