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 186ACC77B75 for ; Fri, 12 May 2023 09:20:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240339AbjELJUV (ORCPT ); Fri, 12 May 2023 05:20:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230486AbjELJUT (ORCPT ); Fri, 12 May 2023 05:20:19 -0400 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5014DD2DC for ; Fri, 12 May 2023 02:20:18 -0700 (PDT) Received: from [192.168.88.20] (91-154-35-171.elisa-laajakaista.fi [91.154.35.171]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 27AE62D8; Fri, 12 May 2023 11:20:06 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1683883207; bh=VWGt5kixjdflXkuIyYInfnTF9iqkcIMqcEq7zHEeUyg=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=LfeCd0790PtQdJvMeHHStWDDAJYIIxXLA5QR3V/hZ0qhjo2DsJlxOmtj86PnaMsWF RCaiF7djORTh6qc7BUOzt3kg4sfO63Ud8mQ7mPomLXPU5DlcfjzFlQNb0m/wG9RTkc ZByDZZfcZUynwdw3yypt3+Gj65+Qq5oVJ2rYUV5w= Message-ID: <37799ac8-b3ad-ad0c-a104-82249ba7b387@ideasonboard.com> Date: Fri, 12 May 2023 12:20:12 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.10.0 Subject: Re: [PATCH v6 0/8] drm/tidss: Use new connector model for tidss Content-Language: en-US To: Aradhya Bhatia , Jyri Sarha , David Airlie , Daniel Vetter , Laurent Pinchart , Andrzej Hajda , Neil Armstrong , Robert Foss , Jonas Karlman , Jernej Skrabec , Rahul T R , Swapnil Jakhade , Boris Brezillon , Francesco Dolcini Cc: DRI Development List , Linux Kernel List , Nishanth Menon , Vignesh Raghavendra , Devarsh Thakkar , Jayesh Choudhary References: <20230509093036.3303-1-a-bhatia1@ti.com> From: Tomi Valkeinen In-Reply-To: <20230509093036.3303-1-a-bhatia1@ti.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/05/2023 12:30, Aradhya Bhatia wrote: > Hi all, > > I have picked up this long standing series from Nikhil Devshatwar[1]. > > This series moves the tidss to using new connectoe model, where the SoC > driver (tidss) creates the connector and all the bridges are attached > with the flag DRM_BRIDGE_ATTACH_NO_CONNECTOR. It also now creates bridge > to support format negotiation and and 'simple' encoder to expose it to > the userspace. > > Since the bridges do not create the connector, the bus_format and > bus_flag is set via atomic hooks. > > Support format negotiations in the tfp410, sii902x and mhdp-8546 bridge > drivers as a first step before moving the connector model. > > These patches were tested on AM625-SK EVM, AM625 SoC based BeaglePlay, > and J721E-SK. Display support for AM625 SoC has not been added upstream > and is a WIP. To test this series on AM625 based platforms, basic > display support patches, (for driver + devicetree), can be found in > the "next_AttachNoConn" branch on my github fork[2]. Not exactly related to this series, but I was testing this with J7 EVM and a Dell DP monitor. I'm seeing DPCD errors quite often, which also sometimes cause link training errors. E.g.: cdns-mhdp8546 a000000.dp-bridge: Failed to read DPCD addr 0 cdns-mhdp8546 a000000.dp-bridge: Failed to adjust Link Training. I tested retrying the read/write when it fails, and that seemed to help a bit, but not always. Are you using the firmware that's on the upstream linux-firmware repo? Tomi