From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f182.google.com (mail-ig0-f182.google.com [209.85.213.182]) by kanga.kvack.org (Postfix) with ESMTP id EC1A16B003B for ; Fri, 9 May 2014 23:25:19 -0400 (EDT) Received: by mail-ig0-f182.google.com with SMTP id uy17so1910041igb.3 for ; Fri, 09 May 2014 20:25:19 -0700 (PDT) Received: from nm40.bullet.mail.ne1.yahoo.com (nm40.bullet.mail.ne1.yahoo.com. [98.138.229.33]) by mx.google.com with ESMTPS id aa7si4486058icc.48.2014.05.09.20.25.19 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Fri, 09 May 2014 20:25:19 -0700 (PDT) References: <1399690747.69805.YahooMailNeo@web160104.mail.bf1.yahoo.com> Message-ID: <1399692147.36921.YahooMailNeo@web160101.mail.bf1.yahoo.com> Date: Fri, 9 May 2014 20:22:27 -0700 (PDT) From: PINTU KUMAR Reply-To: PINTU KUMAR Subject: [MM]: IOMMU and CMA buffer sharing In-Reply-To: <1399690747.69805.YahooMailNeo@web160104.mail.bf1.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: "linux-mm@kvack.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linaro-mm-sig@lists.linaro.org" Hi, =0AI have some queries regarding IOMMU and CMA buffer sharing. =0AWe ha= ve an embedded linux device (kernel 3.10, RAM: 256Mb) in which camera and c= odec supports IOMMU but the display does not support IOMMU. =0AThus for cam= era capture we are using iommu buffers using ION/DMABUF. But for all displa= y rendering we are using CMA buffers. =0ASo, the question is how to achieve= buffer sharing (zero-copy) between Camera and Display using only IOMMU? = =0ACurrently we are achieving zero-copy using CMA. And we are exploring opt= ions to use IOMMU. =0ANow we wanted to know which option is better? To use = IOMMU or CMA? =0AIf anybody have come across these design please share your= thoughts and results. =0AThank You! =0ARegards, =0APintu -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org