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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5557DC00144 for ; Mon, 1 Aug 2022 12:15:45 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E265791E51; Mon, 1 Aug 2022 12:15:39 +0000 (UTC) Received: from mail-ed1-x530.google.com (mail-ed1-x530.google.com [IPv6:2a00:1450:4864:20::530]) by gabe.freedesktop.org (Postfix) with ESMTPS id E8B6B91D8D for ; Mon, 1 Aug 2022 12:15:20 +0000 (UTC) Received: by mail-ed1-x530.google.com with SMTP id m8so13438740edd.9 for ; Mon, 01 Aug 2022 05:15:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc; bh=CVzfo9DdvisneyDXyobtn/e72u2h3ldYCnBHERW/QDg=; b=AzXDGT8PxyvKO2GDmJBHBhkMSyIE+rqMegJ1iSeOWOptSdPzzCOkEv4KXhKyW2pd0C aWS1EOIVCL6Nl5X22R7fZkmVLgSsLMagBd/pGJ2vV6udhZa8NraikeHKLRGLVNORIDUm qS2YsL1gUA+i4jhZy61a44KqSvY1eXMvdVgPNSEHQa8niAJK8pz9y14DwgktEKBdyp1x g0XCgLBvbJfX3WocJDHQu07L2SFQZeyyGXt7l9GIE06i+ykTumxKcZ6AStmkS9jj4WRP kUjGKyCNvtGXpVH0GanQ6LKUUv3chImjv3h5WPZSYMg24Py/tKGrepMsQ9y402jH8Rvl CV8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc; bh=CVzfo9DdvisneyDXyobtn/e72u2h3ldYCnBHERW/QDg=; b=7v8FW3mqoP5QNSGYh7FPziOsDfbwsV+9fEv7/OC8Exa9u0QrnpAVe6XVSagtWWMarS OsMIK5UY3YJjp3n9jhE3VqY3AYugt0Rc1UVoMbJw2wsZxWoPTFlbcJyMtwRLV6noIFvi 2rZUj6JIaz4DsG1ySwQmo5MbygjiBR1qxSs3yMQqZBj/e+7NiE3V4MB0qi8H/ShQWk99 OeSgvm/3/VFRtl9lYrMNeg9Lgn879jJ49gZyvgBLV2wiEC22m2yI+XEk7bVDqkKk6IS8 OTzDONbdjiyMsyVTSVSYWz9qR0BwWorUbD9iiTwtl43tUmQQ3/OugSsArUZquaF74lJ/ XR6w== X-Gm-Message-State: ACgBeo2SNcTA9/eTk3zFVVaGkF0QryvijLK09d8rALvJHyblqtWkOxmt /oCnyRZoiyJfnYPelLp9ZITFDZl7W5Bahe0+Jvk= X-Google-Smtp-Source: AA6agR526khjrrpLYsW1IgG91hYvV5KATrbamHAryv/kbSTBgGUs6YndPqhMLeLaGOlrgw5dvWh8puw+QSBPyXScJgI= X-Received: by 2002:a50:bace:0:b0:43d:370a:e1c1 with SMTP id x72-20020a50bace000000b0043d370ae1c1mr12778947ede.193.1659356118908; Mon, 01 Aug 2022 05:15:18 -0700 (PDT) MIME-Version: 1.0 References: <20220801061956.3wkakhwatvqlngff@pengutronix.de> In-Reply-To: From: Adam Ford Date: Mon, 1 Aug 2022 07:15:07 -0500 Message-ID: Subject: Re: imx8mm lcdif->dsi->adv7535 no video, no errors To: Marco Felsch Content-Type: text/plain; charset="UTF-8" X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Marek Vasut , Jagan Teki , Jernej Skrabec , Laurent Pinchart , Andrzej Hajda , Jonas Karlman , David Airlie , Robert Foss , Sascha Hauer , Neil Armstrong , Linux Kernel Mailing List , dri-devel , Shawn Guo , Marek Szyprowski , Pengutronix Kernel Team , arm-soc , NXP Linux Team Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Aug 1, 2022 at 5:54 AM Adam Ford wrote: > > On Mon, Aug 1, 2022 at 1:20 AM Marco Felsch wrote: > > > > Hi Adam, > > > > On 22-07-30, Adam Ford wrote: > > > Hey all, > > > > > > I am trying to test Jagan's patch series [1] to add support for the > > > samsung dsim bridge which is used on the imx8mm to output DSI video. > > > The DSIM gets the video from the mxsfb, and in my case, the DSI is > > > sent to the adv7535 for connecting to HDMI. > > > > So you're using the NXP recommended evalboard setup :) > > Yes and no. Our design also adds audio to theADV7535 in addition to > the video signal. > For the 8M Plus design, we're looking to see if there are any 4K > DSI->HDMI bridge chips available. > > > > > > I have been able to get the device tree setup and I don't get any > > > errors. The Linux system appears to think the video is connected as > > > determined by modetest: > > > > ... > > > > > Unfortunately, there is no video in my monitor, and my monitor states > > > there is no signal. > > > > This is pretty much known, at least on our side. We also have a few more > > patches on top of the series [1] for fixing the horizontal porches. Our > > current status is that we can get only one mode out of the ADV7535 which > > is 1080P. Our assumption is that the ADV7535 needs some attentions > > (fixes) but we can't verify that since the documentation is under NDA. > > I am glad I am not alone. Thanks for the tip. That gives me > something to investigate. > > > > > If I use NXP's downstream kernel, this same hardware configuration > > > works fine and I can see the video. > > > > This is because of the NXP downstream kernel porch 'calculation' and > > workarounds. The values they are using for calculation don't take any > > mode values into account and instead they are using a table. We don't > > know where those values come from. > > I would think the VESA group would have something like these published. > > > > > I have checked the clk_summary, and the working and non-working > > > conditions both have clock rates that are the same for DSI, LCDIF and > > > related items. The power domains connected to the lcdif and the dsi > > > show they are active. > > > > > > Since I go no errors, and Linux looks like it's happy, I was hoping > > > someone from who better understands the interconnections between all > > > these bridge layers might be able to offer a suggestion of something > > > to investigate and/or try. > > > > > > The kernel repo I am using is from Jagan located here: > > > > > > [1] - https://github.com/openedev/kernel > > > > > > I am not convinced it's a device tree issue since I get no errors when > > > the drivers enumerate, but I can provide my device tree updates if > > > that helps. > > > > Please see above. Our debugging showed that there is a strange behaviour > > of the ADV7535 but we don't have any documentation. > Thanks for the comments. > > I'll look to see what I have for documentation. I know my company > signed a bunch of NDA stuff and we have an HDMI license. I'll go > through NXP's patches to their kernel and compare with whatever > documentation I can find to see if I can make any improvements. I checked our datasheet vault and I found no programming guide for the ADV7535. :-( I've put in a request to see if we can get one. I found one for the adv7511 on Analog Device's web site: https://www.analog.com/media/en/technical-documentation/user-guides/ADV7511_Programming_Guide.pdf They have a table of values for the different resolutions. I am guessing they might be the same or similar for 7535. I'm going to look into NXP's alterations to this driver when I have more time. adam > > adam > > > > Regards, > > Marco 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DD7C6C00144 for ; Mon, 1 Aug 2022 12:32:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:Subject:Message-ID:Date:From: In-Reply-To:References:MIME-Version:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=E5OM7MP9H7t7QLNaBCg6Y+6vnOvNXgCKV2Tfbt9eev8=; 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Mon, 01 Aug 2022 05:15:18 -0700 (PDT) MIME-Version: 1.0 References: <20220801061956.3wkakhwatvqlngff@pengutronix.de> In-Reply-To: From: Adam Ford Date: Mon, 1 Aug 2022 07:15:07 -0500 Message-ID: Subject: Re: imx8mm lcdif->dsi->adv7535 no video, no errors To: Marco Felsch Cc: dri-devel , Marek Vasut , Stefan Agner , Fabio Estevam , Daniel Vetter , Jonas Karlman , David Airlie , Robert Foss , Sascha Hauer , Neil Armstrong , NXP Linux Team , Jernej Skrabec , Linux Kernel Mailing List , Laurent Pinchart , Andrzej Hajda , Marek Szyprowski , Shawn Guo , Pengutronix Kernel Team , arm-soc , Jagan Teki X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220801_051524_480770_C33CAAF2 X-CRM114-Status: GOOD ( 52.48 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Aug 1, 2022 at 5:54 AM Adam Ford wrote: > > On Mon, Aug 1, 2022 at 1:20 AM Marco Felsch wrote: > > > > Hi Adam, > > > > On 22-07-30, Adam Ford wrote: > > > Hey all, > > > > > > I am trying to test Jagan's patch series [1] to add support for the > > > samsung dsim bridge which is used on the imx8mm to output DSI video. > > > The DSIM gets the video from the mxsfb, and in my case, the DSI is > > > sent to the adv7535 for connecting to HDMI. > > > > So you're using the NXP recommended evalboard setup :) > > Yes and no. Our design also adds audio to theADV7535 in addition to > the video signal. > For the 8M Plus design, we're looking to see if there are any 4K > DSI->HDMI bridge chips available. > > > > > > I have been able to get the device tree setup and I don't get any > > > errors. The Linux system appears to think the video is connected as > > > determined by modetest: > > > > ... > > > > > Unfortunately, there is no video in my monitor, and my monitor states > > > there is no signal. > > > > This is pretty much known, at least on our side. We also have a few more > > patches on top of the series [1] for fixing the horizontal porches. Our > > current status is that we can get only one mode out of the ADV7535 which > > is 1080P. Our assumption is that the ADV7535 needs some attentions > > (fixes) but we can't verify that since the documentation is under NDA. > > I am glad I am not alone. Thanks for the tip. That gives me > something to investigate. > > > > > If I use NXP's downstream kernel, this same hardware configuration > > > works fine and I can see the video. > > > > This is because of the NXP downstream kernel porch 'calculation' and > > workarounds. The values they are using for calculation don't take any > > mode values into account and instead they are using a table. We don't > > know where those values come from. > > I would think the VESA group would have something like these published. > > > > > I have checked the clk_summary, and the working and non-working > > > conditions both have clock rates that are the same for DSI, LCDIF and > > > related items. The power domains connected to the lcdif and the dsi > > > show they are active. > > > > > > Since I go no errors, and Linux looks like it's happy, I was hoping > > > someone from who better understands the interconnections between all > > > these bridge layers might be able to offer a suggestion of something > > > to investigate and/or try. > > > > > > The kernel repo I am using is from Jagan located here: > > > > > > [1] - https://github.com/openedev/kernel > > > > > > I am not convinced it's a device tree issue since I get no errors when > > > the drivers enumerate, but I can provide my device tree updates if > > > that helps. > > > > Please see above. Our debugging showed that there is a strange behaviour > > of the ADV7535 but we don't have any documentation. > Thanks for the comments. > > I'll look to see what I have for documentation. I know my company > signed a bunch of NDA stuff and we have an HDMI license. I'll go > through NXP's patches to their kernel and compare with whatever > documentation I can find to see if I can make any improvements. I checked our datasheet vault and I found no programming guide for the ADV7535. :-( I've put in a request to see if we can get one. I found one for the adv7511 on Analog Device's web site: https://www.analog.com/media/en/technical-documentation/user-guides/ADV7511_Programming_Guide.pdf They have a table of values for the different resolutions. I am guessing they might be the same or similar for 7535. I'm going to look into NXP's alterations to this driver when I have more time. adam > > adam > > > > Regards, > > Marco _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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 52354C00144 for ; Mon, 1 Aug 2022 12:36:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231269AbiHAMg2 (ORCPT ); Mon, 1 Aug 2022 08:36:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234350AbiHAMgJ (ORCPT ); Mon, 1 Aug 2022 08:36:09 -0400 Received: from mail-ed1-x535.google.com (mail-ed1-x535.google.com [IPv6:2a00:1450:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 013BDBF40 for ; Mon, 1 Aug 2022 05:15:20 -0700 (PDT) Received: by mail-ed1-x535.google.com with SMTP id b96so3156468edf.0 for ; Mon, 01 Aug 2022 05:15:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc; bh=CVzfo9DdvisneyDXyobtn/e72u2h3ldYCnBHERW/QDg=; b=AzXDGT8PxyvKO2GDmJBHBhkMSyIE+rqMegJ1iSeOWOptSdPzzCOkEv4KXhKyW2pd0C aWS1EOIVCL6Nl5X22R7fZkmVLgSsLMagBd/pGJ2vV6udhZa8NraikeHKLRGLVNORIDUm qS2YsL1gUA+i4jhZy61a44KqSvY1eXMvdVgPNSEHQa8niAJK8pz9y14DwgktEKBdyp1x g0XCgLBvbJfX3WocJDHQu07L2SFQZeyyGXt7l9GIE06i+ykTumxKcZ6AStmkS9jj4WRP kUjGKyCNvtGXpVH0GanQ6LKUUv3chImjv3h5WPZSYMg24Py/tKGrepMsQ9y402jH8Rvl CV8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc; bh=CVzfo9DdvisneyDXyobtn/e72u2h3ldYCnBHERW/QDg=; b=o2dHUdi1VcdceX6zbwfg/bUh4QCHxEFTPf1tKtrJGog+sXTuoYCck2DTw0Wik4wbT4 uXb+nVhDmRAHDQMTzivSaL1/THbgEJDTVgZHE7OIlFrl7cvwswfsFQsp9wlSTXeDI54g M3GUR1EiXou1XMpxtbCXJetiFiKP9SE5L/u1JSsHVEC5UouZ5q3OhJ5Mzx+ggR5/4BZm SkyhfHSHfP1U8LKBtjmF6bZNRdRN1abrBsJDlZXtHu4v84OwvkNSpDGgKBvMm4BCRwD/ eD+hYZMANvGHABjix6GbBWyOjC6cZkr5CeqoTBvN8mi402gFy3KiXuK1f/E+JL9IPpv4 op0Q== X-Gm-Message-State: ACgBeo2ea+G2S5aZcqdPnGJwA38DYtCxjftS+4FGs0sC6PrD1Jfhg2Me HfOwlntTTG2ckFLwo1mjpIQV6LIaoyeLuPfea8IwdkJ7CgmNbQ== X-Google-Smtp-Source: AA6agR526khjrrpLYsW1IgG91hYvV5KATrbamHAryv/kbSTBgGUs6YndPqhMLeLaGOlrgw5dvWh8puw+QSBPyXScJgI= X-Received: by 2002:a50:bace:0:b0:43d:370a:e1c1 with SMTP id x72-20020a50bace000000b0043d370ae1c1mr12778947ede.193.1659356118908; Mon, 01 Aug 2022 05:15:18 -0700 (PDT) MIME-Version: 1.0 References: <20220801061956.3wkakhwatvqlngff@pengutronix.de> In-Reply-To: From: Adam Ford Date: Mon, 1 Aug 2022 07:15:07 -0500 Message-ID: Subject: Re: imx8mm lcdif->dsi->adv7535 no video, no errors To: Marco Felsch Cc: dri-devel , Marek Vasut , Stefan Agner , Fabio Estevam , Daniel Vetter , Jonas Karlman , David Airlie , Robert Foss , Sascha Hauer , Neil Armstrong , NXP Linux Team , Jernej Skrabec , Linux Kernel Mailing List , Laurent Pinchart , Andrzej Hajda , Marek Szyprowski , Shawn Guo , Pengutronix Kernel Team , arm-soc , Jagan Teki Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 1, 2022 at 5:54 AM Adam Ford wrote: > > On Mon, Aug 1, 2022 at 1:20 AM Marco Felsch wrote: > > > > Hi Adam, > > > > On 22-07-30, Adam Ford wrote: > > > Hey all, > > > > > > I am trying to test Jagan's patch series [1] to add support for the > > > samsung dsim bridge which is used on the imx8mm to output DSI video. > > > The DSIM gets the video from the mxsfb, and in my case, the DSI is > > > sent to the adv7535 for connecting to HDMI. > > > > So you're using the NXP recommended evalboard setup :) > > Yes and no. Our design also adds audio to theADV7535 in addition to > the video signal. > For the 8M Plus design, we're looking to see if there are any 4K > DSI->HDMI bridge chips available. > > > > > > I have been able to get the device tree setup and I don't get any > > > errors. The Linux system appears to think the video is connected as > > > determined by modetest: > > > > ... > > > > > Unfortunately, there is no video in my monitor, and my monitor states > > > there is no signal. > > > > This is pretty much known, at least on our side. We also have a few more > > patches on top of the series [1] for fixing the horizontal porches. Our > > current status is that we can get only one mode out of the ADV7535 which > > is 1080P. Our assumption is that the ADV7535 needs some attentions > > (fixes) but we can't verify that since the documentation is under NDA. > > I am glad I am not alone. Thanks for the tip. That gives me > something to investigate. > > > > > If I use NXP's downstream kernel, this same hardware configuration > > > works fine and I can see the video. > > > > This is because of the NXP downstream kernel porch 'calculation' and > > workarounds. The values they are using for calculation don't take any > > mode values into account and instead they are using a table. We don't > > know where those values come from. > > I would think the VESA group would have something like these published. > > > > > I have checked the clk_summary, and the working and non-working > > > conditions both have clock rates that are the same for DSI, LCDIF and > > > related items. The power domains connected to the lcdif and the dsi > > > show they are active. > > > > > > Since I go no errors, and Linux looks like it's happy, I was hoping > > > someone from who better understands the interconnections between all > > > these bridge layers might be able to offer a suggestion of something > > > to investigate and/or try. > > > > > > The kernel repo I am using is from Jagan located here: > > > > > > [1] - https://github.com/openedev/kernel > > > > > > I am not convinced it's a device tree issue since I get no errors when > > > the drivers enumerate, but I can provide my device tree updates if > > > that helps. > > > > Please see above. Our debugging showed that there is a strange behaviour > > of the ADV7535 but we don't have any documentation. > Thanks for the comments. > > I'll look to see what I have for documentation. I know my company > signed a bunch of NDA stuff and we have an HDMI license. I'll go > through NXP's patches to their kernel and compare with whatever > documentation I can find to see if I can make any improvements. I checked our datasheet vault and I found no programming guide for the ADV7535. :-( I've put in a request to see if we can get one. I found one for the adv7511 on Analog Device's web site: https://www.analog.com/media/en/technical-documentation/user-guides/ADV7511_Programming_Guide.pdf They have a table of values for the different resolutions. I am guessing they might be the same or similar for 7535. I'm going to look into NXP's alterations to this driver when I have more time. adam > > adam > > > > Regards, > > Marco