From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756889Ab1LWMam (ORCPT ); Fri, 23 Dec 2011 07:30:42 -0500 Received: from mailout3.w1.samsung.com ([210.118.77.13]:32027 "EHLO mailout3.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756842Ab1LWM2I (ORCPT ); Fri, 23 Dec 2011 07:28:08 -0500 MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: TEXT/PLAIN Date: Fri, 23 Dec 2011 13:27:33 +0100 From: Marek Szyprowski Subject: [PATCH 14/14] common: DMA-mapping: add NON-CONSISTENT attribute In-reply-to: <1324643253-3024-1-git-send-email-m.szyprowski@samsung.com> To: linux-kernel@vger.kernel.org Cc: Benjamin Herrenschmidt , Thomas Gleixner , Andrew Morton , Arnd Bergmann , Stephen Rothwell , microblaze-uclinux@itee.uq.edu.au, linux-arch@vger.kernel.org, x86@kernel.org, linux-sh@vger.kernel.org, linux-alpha@vger.kernel.org, sparclinux@vger.kernel.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-mips@linux-mips.org, discuss@x86-64.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linaro-mm-sig@lists.linaro.org, Jonathan Corbet , Marek Szyprowski , Kyungmin Park , Andrzej Pietrasiewicz Message-id: <1324643253-3024-15-git-send-email-m.szyprowski@samsung.com> X-Mailer: git-send-email 1.7.7.3 References: <1324643253-3024-1-git-send-email-m.szyprowski@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org DMA_ATTR_NON_CONSISTENT lets the platform to choose to return either consistent or non-consistent memory as it sees fit. By using this API, you are guaranteeing to the platform that you have all the correct and necessary sync points for this memory in the driver should it choose to return non-consistent memory. Signed-off-by: Marek Szyprowski Signed-off-by: Kyungmin Park --- Documentation/DMA-attributes.txt | 9 +++++++++ include/linux/dma-attrs.h | 1 + 2 files changed, 10 insertions(+), 0 deletions(-) diff --git a/Documentation/DMA-attributes.txt b/Documentation/DMA-attributes.txt index 811a5d4..9120de2 100644 --- a/Documentation/DMA-attributes.txt +++ b/Documentation/DMA-attributes.txt @@ -41,3 +41,12 @@ buffered to improve performance. Since it is optional for platforms to implement DMA_ATTR_WRITE_COMBINE, those that do not will simply ignore the attribute and exhibit default behavior. + +DMA_ATTR_NON_CONSISTENT +----------------------- + +DMA_ATTR_NON_CONSISTENT lets the platform to choose to return either +consistent or non-consistent memory as it sees fit. By using this API, +you are guaranteeing to the platform that you have all the correct and +necessary sync points for this memory in the driver should it choose to +return non-consistent memory. diff --git a/include/linux/dma-attrs.h b/include/linux/dma-attrs.h index ada61e1..547ab56 100644 --- a/include/linux/dma-attrs.h +++ b/include/linux/dma-attrs.h @@ -14,6 +14,7 @@ enum dma_attr { DMA_ATTR_WRITE_BARRIER, DMA_ATTR_WEAK_ORDERING, DMA_ATTR_WRITE_COMBINE, + DMA_ATTR_NON_CONSISTENT, DMA_ATTR_MAX, }; -- 1.7.1.569.g6f426