From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from galahad.ideasonboard.com ([185.26.127.97]:48479 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753989AbbIINUQ (ORCPT ); Wed, 9 Sep 2015 09:20:16 -0400 From: Laurent Pinchart To: Sakari Ailus Cc: linux-media@vger.kernel.org, pawel@osciak.com, m.szyprowski@samsung.com, kyungmin.park@samsung.com, hverkuil@xs4all.nl, Sumit Semwal , Rob Clark , Daniel Vetter , Laura Abbott Subject: Re: [RFC 00/11] vb2: Handle user cache hints, allow drivers to choose cache coherency Date: Wed, 09 Sep 2015 16:20:14 +0300 Message-ID: <2585884.0AruC9DFGi@avalon> In-Reply-To: <1441708435-12736-1-git-send-email-sakari.ailus@linux.intel.com> References: <1441708435-12736-1-git-send-email-sakari.ailus@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org List-ID: + Sumit, Rob, Laura and Daniel who have discussed cache optimization with me at LPC in the context of dmabuf. The full patch set can be found at https://www.mail-archive.com/linux-media@vger.kernel.org/msg92120.html On Tuesday 08 September 2015 13:33:44 Sakari Ailus wrote: > Hi folks, > > This RFC patchset achieves two main objectives: > > 1. Respects cache flags passed from the user space. As no driver nor > videobuf2 has (ever?) implemented them, the two flags are replaced by a > single one (V4L2_BUF_FLAG_NO_CACHE_SYNC) and the two old flags are > deprecated. This is done since a single flag provides the driver with > enough information on what to do. (See more info in patch 4.) > > 2. Allows a driver using videobuf2 dma-contig memory type to choose > whether it prefers coherent or non-coherent CPU access to buffer memory > for MMAP and USERPTR buffers. This could be later extended to be specified > by the user, and per buffer if needed. > > Only dma-contig memory type is changed but the same could be done to > dma-sg as well. I can add it to the set if people are happy with the > changes to dma-contig. -- Regards, Laurent Pinchart