From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Szyprowski Subject: RE: [PATCH 0/1] v4l: videobuf2: Add DMA pool allocator Date: Mon, 17 Jan 2011 16:48:11 +0100 Message-ID: <008f01cbb65d$f4c33a40$de49aec0$%szyprowski@samsung.com> References: <1293684907-7272-1-git-send-email-jtp.park@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7BIT Return-path: Received: from mailout4.samsung.com ([203.254.224.34]:11085 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752040Ab1AQPsS (ORCPT ); Mon, 17 Jan 2011 10:48:18 -0500 In-reply-to: <1293684907-7272-1-git-send-email-jtp.park@samsung.com> Content-language: pl Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: 'Jeongtae Park' , linux-media@vger.kernel.org, linux-samsung-soc@vger.kernel.org Cc: k.debski@samsung.com, jaeryul.oh@samsung.com, jonghun.han@samsung.com, kgene.kim@samsung.com Hello, On Thursday, December 30, 2010 5:55 AM Jeongtae Park wrote: > The DMA pool allocator allocates a memory using dma_alloc_coherent(), > creates a pool using generic allocator in the initialization. > For every allocation requests, the allocator returns a part of its > memory pool using generic allocator instead of new memory allocation. > > This allocator used for devices have below limitations. > - the start address should be aligned > - the range of memory access limited to the offset from the start > address (= the allocation address should be existed in a > constant offset from the start address) > - the allocation address should be aligned > > I would be grateful for your comments. > > This patch series contains: > > [PATCH 1/1] v4l: videobuf2: Add DMA pool allocator > > Best regards, > Jeongtae Park > > Patch summary: > > Jeongtae Park (1): > v4l: videobuf2: Add DMA pool allocator > > drivers/media/video/Kconfig | 7 + > drivers/media/video/Makefile | 1 + > drivers/media/video/videobuf2-dma-pool.c | 310 ++++++++++++++++++++++++++++++ > include/media/videobuf2-dma-pool.h | 37 ++++ > 4 files changed, 355 insertions(+), 0 deletions(-) > create mode 100644 drivers/media/video/videobuf2-dma-pool.c > create mode 100644 include/media/videobuf2-dma-pool.h The code looks nice but I have one suggestion. This dma-pool memory allocator make sense only for a s5p-mfc driver. All other drivers can use dma-contig vb2 allocator directly. For this reason I suggest to move this allocator directly to drivers/media/video/s5p-mfc/ directory. Best regards -- Marek Szyprowski Samsung Poland R&D Center