From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61E98C19F2B for ; Thu, 4 Aug 2022 09:57:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239201AbiHDJ5f (ORCPT ); Thu, 4 Aug 2022 05:57:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41092 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231982AbiHDJ5d (ORCPT ); Thu, 4 Aug 2022 05:57:33 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51EA66610F for ; Thu, 4 Aug 2022 02:57:31 -0700 (PDT) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oJXbR-000870-GW; Thu, 04 Aug 2022 11:57:17 +0200 Received: from mfe by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1oJXbP-0007zS-7a; Thu, 04 Aug 2022 11:57:15 +0200 Date: Thu, 4 Aug 2022 11:57:15 +0200 From: Marco Felsch To: Adam Ford Cc: Dave Stevenson , Neil Armstrong , David Airlie , dri-devel , Laurent Pinchart , Andrzej Hajda , Marek Szyprowski , Marek Vasut , Jernej Skrabec , Jagan Teki , robert.chiras@nxp.com, laurentiu.palcu@nxp.com, NXP Linux Team , Jonas Karlman , Sascha Hauer , arm-soc , Linux Kernel Mailing List , Robert Foss , Pengutronix Kernel Team , Shawn Guo Subject: Re: imx8mm lcdif->dsi->adv7535 no video, no errors Message-ID: <20220804095715.d3ay7yvn2adxdo4x@pengutronix.de> References: <20220802080820.jyf3tfpgcj3pvbtp@pengutronix.de> <20220803062024.vn7awasmifkp5xow@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180716 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: mfe@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 22-08-03, Adam Ford wrote: > On Wed, Aug 3, 2022 at 7:17 AM Dave Stevenson ... > > Not meaning to butt in, but I have datasheets for ADV7533 and 7535 > > from previously looking at these chips. > > Thanks for the feedback. > > > Mine fairly plainly states: > > "The DSI receiver input supports DSI video mode operation only, and > > specifically, only supports nonburst mode with sync pulses". > > Non-burst mode meaning that the DSI pixel rate MUST be the same as the > > HDMI pixel rate. > > Mine also states the DSI source needs to provide correct video timing > with start and stop sync packets. > > If I remember correctly, it seemed like Marek V wanted the hard coded > samsung,burst-clock-frequency to go away so the clock frequency could > be set dynamically. As previously said, this is something on our TODO list too :) but needs a bit more infrastructure work. > I have attempted to do some of this work based on what I am seeing in > the NXP kernel, and I get get my monitor to sync at some resolutions, > but the screen is usually all green or all blue, so it's not really a > success. The clock part appears to be good enough to make the monitor > see some sort of signal, so I am going to investigate the calculation > of the rest of the video timings to see if I can fix the color issue. Please don't pay to much attention to the NXP kernel. No one have a glue where those porches came from. If I specify the burst-clock-freq. to 445.5 and set the lane number to 4 and hack in the porches values from NXP, than I get a 720P output too. But this isn't the way to go instead we should calc the porches settings and the burst-clock-frequency dynamiclly to provide more than just a few resolutions. But for that we need a clear understanding of how the ADV is working. I will prepare a repo to day and will send you a link with the hack patches in it, so you can test it :) Regards, Marco