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 X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1EDEBC433DF for ; Fri, 10 Jul 2020 01:38:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DCA4B206A1 for ; Fri, 10 Jul 2020 01:38:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="kxMyTpnO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726446AbgGJBis (ORCPT ); Thu, 9 Jul 2020 21:38:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726433AbgGJBis (ORCPT ); Thu, 9 Jul 2020 21:38:48 -0400 Received: from mail-ua1-x942.google.com (mail-ua1-x942.google.com [IPv6:2607:f8b0:4864:20::942]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AACFCC08C5DC for ; Thu, 9 Jul 2020 18:38:47 -0700 (PDT) Received: by mail-ua1-x942.google.com with SMTP id j21so1326144ual.11 for ; Thu, 09 Jul 2020 18:38:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=rwZ3DYshMM6TxgS7HlmiJMG3O0eqLFDjVA0qiqONL9c=; b=kxMyTpnOoVqLAx06Eq/BG8dsTt2HetQM+osslhZwLZLc6qwsmlW+bGHiIJ4xrH96dS b8Z4AmXJ6eAlGURzDiRvOaW6caIuXF3dnOU9Me9Ji2G9SrPTWdoTpsd8DSYGzmMWDoCP 9QKK+ffBMstJ7DjkzVsc4yRl/QNqfbFX9q+ZY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=rwZ3DYshMM6TxgS7HlmiJMG3O0eqLFDjVA0qiqONL9c=; b=NngxFoRye4uB8qws7snkIJnFnAED38mDFhALBmfUV28C6TLzDY3sPZ9ZCfxJ8iYUog f9t57x3iTC0zluNjV/ADCQnMkWxwm8uKqGkEGZnAE+qrVU3w6hVCU1NglAi7QHYGUnGQ cUVXuerGk6snMUdRics+MwdKMcPx1bjTuLKOtjUoNR73kzXdlKUYbRPkpGk7RkAibE5Z vU7bOjYqU029jiz3m9bKxmfGmg9HRS/dZNsat9fdVG8YN5Jtidjdi+lm8CEVYxYypDLW BjKTXFAwqBvMTeJoKMPY69P3h3u6kdUCmdtM9Pg17HYS1/T2LInEtjwamIEPoWC3dXLf SPMw== X-Gm-Message-State: AOAM531dVKlZIi5joJC98ZGAM7TgLY9YSNJDDYYurLArsqD9xSYKug9W +apkWyqY1x1NPgweCiujkcFMtaCm2CQ= X-Google-Smtp-Source: ABdhPJzTxts4BDPGHBIKTgxeXMEy/z9MEXs9q8WrCg5glZrIqSIyPuHPJ2V8b+IT+INtekP+6cihJw== X-Received: by 2002:a9f:320c:: with SMTP id x12mr12597169uad.45.1594345126329; Thu, 09 Jul 2020 18:38:46 -0700 (PDT) Received: from mail-vs1-f49.google.com (mail-vs1-f49.google.com. [209.85.217.49]) by smtp.gmail.com with ESMTPSA id i7sm528362vsi.10.2020.07.09.18.38.43 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 09 Jul 2020 18:38:44 -0700 (PDT) Received: by mail-vs1-f49.google.com with SMTP id a17so2153526vsq.6 for ; Thu, 09 Jul 2020 18:38:43 -0700 (PDT) X-Received: by 2002:a67:e046:: with SMTP id n6mr20302730vsl.6.1594345122863; Thu, 09 Jul 2020 18:38:42 -0700 (PDT) MIME-Version: 1.0 References: <20191218143416.v3.6.Iaf8d698f4e5253d658ae283d2fd07268076a7c27@changeid> <20200710011935.GA7056@gentoo.org> In-Reply-To: <20200710011935.GA7056@gentoo.org> From: Doug Anderson Date: Thu, 9 Jul 2020 18:38:31 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v3 6/9] drm/bridge: ti-sn65dsi86: Use 18-bit DP if we can To: steev@kali.org Cc: Laurent Pinchart , Andrzej Hajda , David Airlie , Bjorn Andersson , Daniel Vetter , dri-devel , Jeffrey Hugo , Jernej Skrabec , Jonas Karlman , linux-arm-msm , LKML , Neil Armstrong , Rob Clark , Rob Clark , Sean Paul , Steev Klimaszewski Content-Type: text/plain; charset="UTF-8" Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Hi, On Thu, Jul 9, 2020 at 6:19 PM Steev Klimaszewski wrote: > > Hi Doug, > > I've been testing 5.8 and linux-next on the Lenovo Yoga C630, and with this patch applied, there is really bad banding on the display. > > I'm really bad at explaining it, but you can see the differences in the following: > > 24bit (pre-5.8) - https://dev.gentoo.org/~steev/files/image0.jpg > > 18bit (5.8/linux-next) - https://dev.gentoo.org/~steev/files/image1.jpg Presumably this means that your panel is defined improperly? If the panel reports that it's a 6 bits per pixel panel but it's actually an 8 bits per pixel panel then you'll run into this problem. I would have to assume you have a bunch of out of tree patches to support your hardware since I don't see any device trees in linuxnext (other than cheza) that use this bridge chip. Otherwise I could try to check and confirm that was the problem. -Doug