From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from moutng.kundenserver.de ([212.227.126.187]:52944 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753038Ab1CNNc1 (ORCPT ); Mon, 14 Mar 2011 09:32:27 -0400 From: Arnd Bergmann To: KyongHo Cho Subject: Re: [PATCH 3/7] ARM: Samsung: update/rewrite Samsung SYSMMU (IOMMU) driver Date: Mon, 14 Mar 2011 14:32:19 +0100 Cc: Marek Szyprowski , linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-media@vger.kernel.org, Tomasz Stanislawski , k.debski@samsung.com, kgene.kim@samsung.com, kyungmin.park@samsung.com, Sylwester Nawrocki , Andrzej Pietrasiewicz , =?utf-8?q?=EB=8C=80=EC=9D=B8=EA=B8=B0?= , =?utf-8?q?=EA=B0=95=EB=AF=BC=EA=B7=9C?= , linux-kernel@vger.kernel.org References: <1299229274-9753-4-git-send-email-m.szyprowski@samsung.com> <201103111700.17373.arnd@arndb.de> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201103141432.19614.arnd@arndb.de> List-ID: Sender: On Monday 14 March 2011, KyongHo Cho wrote: > I think we can consider another solution for the various requirements. > I think one of the most possible solutions is VCMM. > Or we can enhance include/linux/iommu.h with reference of VCMM. I think extending or changing the existing interface would be much preferred. It's always better to limit the number of interfaces that do the same thing, and we already have more duplication than we want with the two dma-mapping.h and iommu.h interfaces. Note that any aspect of the existing interface can be changed if necessary, as long as there is a way to migrate all the existing users. Since the iommu API is not exported to user space, there is no requirement to keep it stable. Arnd