Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753856Ab0HZOOy (ORCPT ); Thu, 26 Aug 2010 10:14:54 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:41012 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753813Ab0HZOOw convert rfc822-to-8bit (ORCPT ); Thu, 26 Aug 2010 10:14:52 -0400 From: "Guzman Lugo, Fernando" To: FUJITA Tomonori CC: "linux-omap@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "ohad@wizery.com" , "hiroshi.doyu@nokia.com" , "ameya.palande@nokia.com" , "felipe.contreras@nokia.com" Date: Thu, 26 Aug 2010 09:13:16 -0500 Subject: RE: [PATCH 8/9] dspbridge: add map support for big buffers Thread-Topic: [PATCH 8/9] dspbridge: add map support for big buffers Thread-Index: ActFJ29is6oB/tQ5RGOIv/ZsjaVfHAAAWRLC Message-ID: <496565EC904933469F292DDA3F1663E602F10ED4B4@dlee06.ent.ti.com> References: <496565EC904933469F292DDA3F1663E602F10ED4B1@dlee06.ent.ti.com> <20100826215554N.fujita.tomonori@lab.ntt.co.jp> <496565EC904933469F292DDA3F1663E602F10ED4B3@dlee06.ent.ti.com>,<20100826230139Y.fujita.tomonori@lab.ntt.co.jp> In-Reply-To: <20100826230139Y.fujita.tomonori@lab.ntt.co.jp> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1753 Lines: 37 ________________________________________ >From: FUJITA Tomonori [fujita.tomonori@lab.ntt.co.jp] >Sent: Thursday, August 26, 2010 9:03 AM >To: Guzman Lugo, Fernando >Cc: fujita.tomonori@lab.ntt.co.jp; linux-omap@vger.kernel.org; linux-kernel@vger.kernel.org; ohad@wizery.com; hiroshi.doyu@nokia.com; ameya.palande@nokia.com; >felipe.contreras@nokia.com >Subject: RE: [PATCH 8/9] dspbridge: add map support for big buffers > >On Thu, 26 Aug 2010 08:16:24 -0500 >"Guzman Lugo, Fernando" wrote: > >> >From a quick look, arch/arm/plat-omap/iovmm.c does nothing wrong about >> >scatter gather chaining. arm/arm/mm/dma-mapping.c looks fine too about >> >it. Maybe just defining ARCH_HAS_SG_CHAIN works? >> >> I can try, but it looks tricky for me. Maybe someone else can tell us why >> SG chain is not supported for ARM or if there is a problem just defining >> ARCH_HAS_SG_CHAIN. > >I suppose that nobody in ARM has been interested in the feature. It >was invented to improve I/O performance with large I/O requests. No >wonder embeded people aren't interested in it. > >fujita@rose:~/git/linux-2.6$ find arch -name 'scatterlist.h'|xargs grep HAS_SG >arch/x86/include/asm/scatterlist.h:#define ARCH_HAS_SG_CHAIN >arch/ia64/include/asm/scatterlist.h:#define ARCH_HAS_SG_CHAIN >arch/sparc/include/asm/scatterlist.h:#define ARCH_HAS_SG_CHAIN >arch/powerpc/include/asm/scatterlist.h:#define ARCH_HAS_SG_CHAIN Ok, so let me try SG chain, that should be the correct fix. Thanks a lot, Fernando. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/