From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from moutng.kundenserver.de ([212.227.126.171]:63453 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752052Ab1CJOwT (ORCPT ); Thu, 10 Mar 2011 09:52:19 -0500 From: Arnd Bergmann To: linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 3/7] ARM: Samsung: update/rewrite Samsung SYSMMU (IOMMU) driver Date: Thu, 10 Mar 2011 15:52:15 +0100 Cc: Marek Szyprowski , linux-samsung-soc@vger.kernel.org, linux-media@vger.kernel.org, t.stanislaws@samsung.com, k.debski@samsung.com, kgene.kim@samsung.com, kyungmin.park@samsung.com, s.nawrocki@samsung.com, andrzej.p@samsung.com References: <1299229274-9753-4-git-send-email-m.szyprowski@samsung.com> <1299254660-15765-1-git-send-email-m.szyprowski@samsung.com> In-Reply-To: <1299254660-15765-1-git-send-email-m.szyprowski@samsung.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201103101552.15536.arnd@arndb.de> List-ID: Sender: On Friday 04 March 2011, Marek Szyprowski wrote: > From: Andrzej Pietrasiewicz > > This patch performs a complete rewrite of sysmmu driver for Samsung platform: > - the new version introduces an api to construct device private page > tables and enables to use device private address space mode > - simplified the resource management: no more single platform > device with 32 resources is needed, better fits into linux driver model, > each sysmmu instance has it's own resource definition > - added support for sysmmu clocks > - some other minor API chages required by upcoming videobuf2 allocator > > Signed-off-by: Andrzej Pietrasiewicz > Signed-off-by: Kyungmin Park > Signed-off-by: Marek Szyprowski Please explain why create a new IOMMU API when we already have two generic ones (include/linux/iommu.h and include/linux/dma-mapping.h). Is there something that cannot be done with the common code? The first approach should be to extend the existing APIs to do what you need. Arnd