From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752469AbdAaNRP (ORCPT ); Tue, 31 Jan 2017 08:17:15 -0500 Received: from pandora.armlinux.org.uk ([78.32.30.218]:56636 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752329AbdAaNP4 (ORCPT ); Tue, 31 Jan 2017 08:15:56 -0500 Date: Tue, 31 Jan 2017 13:14:36 +0000 From: Russell King - ARM Linux To: Philipp Zabel Cc: Steve Longerbeam , Hans Verkuil , robh+dt@kernel.org, mark.rutland@arm.com, shawnguo@kernel.org, kernel@pengutronix.de, fabio.estevam@nxp.com, mchehab@kernel.org, nick@shmanahar.org, markus.heiser@darmarIT.de, laurent.pinchart+renesas@ideasonboard.com, bparrot@ti.com, geert@linux-m68k.org, arnd@arndb.de, sudipm.mukherjee@gmail.com, minghsiu.tsai@mediatek.com, tiffany.lin@mediatek.com, jean-christophe.trotin@st.com, horms+renesas@verge.net.au, niklas.soderlund+renesas@ragnatech.se, robert.jarzmik@free.fr, songjun.wu@microchip.com, andrew-ct.chen@mediatek.com, gregkh@linuxfoundation.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, devel@driverdev.osuosl.org, Steve Longerbeam , Laurent Pinchart Subject: Re: [PATCH v3 00/24] i.MX Media Driver Message-ID: <20170131131436.GW27312@n2100.armlinux.org.uk> References: <1483755102-24785-1-git-send-email-steve_longerbeam@mentor.com> <1484929911.2897.70.camel@pengutronix.de> <3fb68686-9447-2d8a-e2d2-005e4138cd43@gmail.com> <5d23d244-aa0e-401c-24a9-07f28acf1563@xs4all.nl> <1485169204.2874.57.camel@pengutronix.de> <1485257269.3600.96.camel@pengutronix.de> <20170130130657.GR27312@n2100.armlinux.org.uk> <1485857364.2932.27.camel@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1485857364.2932.27.camel@pengutronix.de> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 31, 2017 at 11:09:24AM +0100, Philipp Zabel wrote: > On Mon, 2017-01-30 at 13:06 +0000, Russell King - ARM Linux wrote: > > To help illustrate my point, consider the difference between > > MEDIA_BUS_FMT_RGB565_1X16 and MEDIA_BUS_FMT_RGB565_2X8_BE or > > MEDIA_BUS_FMT_RGB565_2X8_LE. RGB565_1X16 means 1 pixel over an effective > > 16-bit wide bus (if it's not 16-bit, then it has to be broken up into > > separate "samples".) RGB565_2X8 means 1 pixel as two 8-bit samples. > > > > So, the 10-bit bayer is 1 pixel as 1.25 bytes. Or is it, over a serial > > bus. Using the RGB565 case, 10-bit bayer over a 4 lane CSI bus becomes > > interesting: > > > > first byte 2nd 3rd > > lane 1 P0 9:2 S0 P7 9:2 > > lane 2 P1 9:2 P4 9:2 S1 > > lane 3 P2 9:2 P5 9:2 P8 9:2 > > lane 4 P3 9:2 P6 9:2 P9 9:2 > > > > S0 = P0/P1/P2/P3 least significant two bits > > S1 = P4/P5/P6/P7 least significant two bits > > > > or 2 lane CSI: > > first byte 2nd 3rd 4th 5th > > lane 1 P0 9:2 P2 S0 P5 P7 > > lane 2 P1 9:2 P3 P4 P6 S1 > > > > or 1 lane CSI: > > lane 1 P0 P1 P2 P3 S0 P4 P5 P6 P7 S1 P8 P9 ... > > These do look like three different media bus formats to me. This isn't limited to the serial side - the parallel bus side between the CSI2 interface and CSI2IPU wrapper, and the CSI2IPU wrapper and the CS0/1 interfaces is much the same with 10-bit bayer. Think of the CSI2 <-> CSI2IPU bit as the 4-lane case, lane 0 ending up on the least significant 8 bits of the 32-bit bus, lane 3 on the top 8-bits. Post CSI2IPU, it talks about a 16-bit bus in the diagrams, so that's kind of the 2-lane case above... -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.