From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wy0-f177.google.com ([74.125.82.177]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1RPswH-0005yx-Fh for barebox@lists.infradead.org; Mon, 14 Nov 2011 09:34:54 +0000 Received: by wyi11 with SMTP id 11so5519701wyi.36 for ; Mon, 14 Nov 2011 01:34:50 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <8739drj2pf.fsf@free.fr> References: <8739drj2pf.fsf@free.fr> Date: Mon, 14 Nov 2011 12:34:50 +0300 Message-ID: From: Antony Pavlov List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: Barebox newbie questions : arch/arm/{plat, mach} split and interrupts To: Robert Jarzmik Cc: barebox@lists.infradead.org On 13 November 2011 22:29, Robert Jarzmik wrote: > As I'm a bit new to barebone, and after reading a bit the code for the ARM > architectures, I have questions : > > ... > > =A0(2) In arch/arm, I understand that interruptions are never used (do_ir= q() > =A0 =A0 implementation is quite clear about that). Is that a design decis= ion and > =A0 =A0 why ? > =A0 =A0 If so, I suppose that active polling for each device is required.= Am I > =A0 =A0 right here ? > Barebox is a firmware. So there are two main requirements for firmware: * easy adaptation for new board (new board revision); * small RAM/ROM footprint. No interrupt support will help you to fulfill the both requirements. Moreover, if you have a board with some interrupt damage (e.g. PCI interrupt pin broken or erroneously routed) you can start firmware and easy find the problem. But if your firmware use the interrupts and your board have broken PCI interrupts and console on RS232 connected via PCI when ... you will have very funny hardware quest :))) -- = Best regards, =A0 Antony Pavlov _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox