Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751717AbdGaAsG (ORCPT ); Sun, 30 Jul 2017 20:48:06 -0400 Received: from out20-39.mail.aliyun.com ([115.124.20.39]:56703 "EHLO out20-39.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751641AbdGaAsD (ORCPT ); Sun, 30 Jul 2017 20:48:03 -0400 X-Alimail-AntiSpam: AC=CONTINUE;BC=0.08504315|-1;FP=0|0|0|0|0|-1|-1|-1;HT=e02c03305;MF=yong.deng@magewell.com;NM=1;PH=DS;RN=25;RT=25;SR=0;TI=SMTPD_---.8XZeJXP_1501462063; Date: Mon, 31 Jul 2017 08:47:44 +0800 From: Yong To: Maxime Ripard Cc: Baruch Siach , Mauro Carvalho Chehab , Rob Herring , Mark Rutland , Chen-Yu Tsai , Greg Kroah-Hartman , "David S. Miller" , Hans Verkuil , Arnd Bergmann , Hugues Fruchet , Yannick Fertre , Philipp Zabel , Benoit Parrot , Benjamin Gaignard , Jean-Christophe Trotin , Ramesh Shanmugasundaram , Minghsiu Tsai , Krzysztof Kozlowski , Robert Jarzmik , linux-media@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com Subject: Re: [PATCH v2 1/3] media: V3s: Add support for Allwinner CSI. Message-Id: <20170731084744.3d8d9f632858241c54efd185@magewell.com> In-Reply-To: <20170727122551.qca4atjeet6whfrs@flea.lan> References: <1501131697-1359-1-git-send-email-yong.deng@magewell.com> <1501131697-1359-2-git-send-email-yong.deng@magewell.com> <20170727121644.jtpge4x432gfxhvw@tarshish> <20170727122551.qca4atjeet6whfrs@flea.lan> X-Mailer: Sylpheed 3.6.0 (GTK+ 2.24.30; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1648 Lines: 52 On Thu, 27 Jul 2017 14:25:51 +0200 Maxime Ripard wrote: > On Thu, Jul 27, 2017 at 03:16:44PM +0300, Baruch Siach wrote: > > Hi Yong, > > > > I managed to get the Frame Done interrupt with the previous version of this > > driver on the A33 OLinuXino. No data yet (all zeros). I'm still working on it. > > > > One comment below. > > > > On Thu, Jul 27, 2017 at 01:01:35PM +0800, Yong Deng wrote: > > > Allwinner V3s SoC have two CSI module. CSI0 is used for MIPI interface > > > and CSI1 is used for parallel interface. This is not documented in > > > datasheet but by testing and guess. > > > > > > This patch implement a v4l2 framework driver for it. > > > > > > Currently, the driver only support the parallel interface. MIPI-CSI2, > > > ISP's support are not included in this patch. > > > > > > Signed-off-by: Yong Deng > > > --- > > > > [...] > > > > > +static int update_buf_addr(struct sun6i_csi *csi, dma_addr_t addr) > > > +{ > > > + struct sun6i_csi_dev *sdev = sun6i_csi_to_dev(csi); > > > + /* transform physical address to bus address */ > > > + dma_addr_t bus_addr = addr - 0x40000000; > > > > What is the source of this magic number? Is it platform dependent? Are there > > other devices doing DMA that need this adjustment? > > This is the RAM base address in most (but not all) Allwinner > SoCs. You'll want to use PHYS_OFFSET instead. I have try to use PHYS_OFFSET. But I found it is not 0x40000000. I will try it again. > > Maxime > > -- > Maxime Ripard, Free Electrons > Embedded Linux and Kernel engineering > http://free-electrons.com Thanks, Yong