From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brad Boyer Subject: Re: [PATCH] ata: libata depends on HAS_DMA Date: Tue, 12 May 2009 21:34:09 -0700 Message-ID: <20090513043409.GA13577@cynthia.pants.nu> References: <20090511222702.352192505@arndb.de> <200905112238.55404.arnd@arndb.de> <20090512090602.65722342@lxorguk.ukuu.org.uk> <200905121123.21436.arnd@arndb.de> <20090513033027.GA13193@cynthia.pants.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-m68k-owner@vger.kernel.org To: Michael Schmitz Cc: Arnd Bergmann , Alan Cox , linux-kernel@vger.kernel.org, Jeff Garzik , linux-ide@vger.kernel.org, takata@linux-m32r.org, geert@linux-m68k.org, linux-m68k@lists.linux-m68k.org, ysato@users.sourceforge.jp List-Id: linux-ide@vger.kernel.org On Wed, May 13, 2009 at 06:12:31AM +0200, Michael Schmitz wrote: > The Atari IDE interface does not use DMA. I don't see what addition of DMA > mapping for IDE would achieve. The macide driver doesn't support anything with DMA hardware either. In fact, no m68k Macintosh has both DMA capability and an IDE controller. However, we do support the basic DMA routines on the main m68k platforms. It's just not used for IDE. I think the proposed change was to require that the DMA routines be present, not that the IDE ports actually have to have a DMA capability. > If it doesn't interfere with plain PIO mode, fine. I agree. There definitely needs to still be support for IDE ports that don't have DMA capability. Brad Boyer flar@allandria.com From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751910AbZEMEf0 (ORCPT ); Wed, 13 May 2009 00:35:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751458AbZEMEfK (ORCPT ); Wed, 13 May 2009 00:35:10 -0400 Received: from [76.245.85.235] ([76.245.85.235]:41152 "EHLO cynthia.pants.nu" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750998AbZEMEfJ (ORCPT ); Wed, 13 May 2009 00:35:09 -0400 Date: Tue, 12 May 2009 21:34:09 -0700 From: Brad Boyer To: Michael Schmitz Cc: Arnd Bergmann , Alan Cox , linux-kernel@vger.kernel.org, Jeff Garzik , linux-ide@vger.kernel.org, takata@linux-m32r.org, geert@linux-m68k.org, linux-m68k@vger.kernel.org, ysato@users.sourceforge.jp Subject: Re: [PATCH] ata: libata depends on HAS_DMA Message-ID: <20090513043409.GA13577@cynthia.pants.nu> References: <20090511222702.352192505@arndb.de> <200905112238.55404.arnd@arndb.de> <20090512090602.65722342@lxorguk.ukuu.org.uk> <200905121123.21436.arnd@arndb.de> <20090513033027.GA13193@cynthia.pants.nu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 13, 2009 at 06:12:31AM +0200, Michael Schmitz wrote: > The Atari IDE interface does not use DMA. I don't see what addition of DMA > mapping for IDE would achieve. The macide driver doesn't support anything with DMA hardware either. In fact, no m68k Macintosh has both DMA capability and an IDE controller. However, we do support the basic DMA routines on the main m68k platforms. It's just not used for IDE. I think the proposed change was to require that the DMA routines be present, not that the IDE ports actually have to have a DMA capability. > If it doesn't interfere with plain PIO mode, fine. I agree. There definitely needs to still be support for IDE ports that don't have DMA capability. Brad Boyer flar@allandria.com