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 84E5AC433FE for ; Fri, 4 Feb 2022 22:37:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351015AbiBDWhT (ORCPT ); Fri, 4 Feb 2022 17:37:19 -0500 Received: from mail-oo1-f54.google.com ([209.85.161.54]:42799 "EHLO mail-oo1-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233433AbiBDWhS (ORCPT ); Fri, 4 Feb 2022 17:37:18 -0500 Received: by mail-oo1-f54.google.com with SMTP id w5-20020a4a9785000000b0030956914befso6250853ooi.9; Fri, 04 Feb 2022 14:37:18 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=1Xkm+wQR2CLWbK9ZiKadmiL63/Ces5dU1DXtwlkexAk=; b=FYt81DfnK3fJY7ZvdMVR4STrcT7U2uMCKcdeGEg4x+Xz/KrIWQcx9xURQCORntJRAc msv7F5ZRgF3Qpy/9A7SmeIJyzzUrJlxxSXrSckh37gJ+o//msScaRCBy57nVrqHJ48jG QGEyRZlUF9aKNcFXBOGn+Ibihwj47Xq7oE4eFFIEn3zZVpli5JAmCxgo3w19bJtzYE0e KTdYKF9APJXWERIlgwDR0rU2hE/h2F0h7n7YtXAV4upbQSVVqNqnIS6uAD+SPNkuZN7b 0BpawghAtr4tFuYlT4CNXlyP6c3xGjNbeYxkRTFA9mqkeDHoDDSYXACMhkc2DZPJVNoG xmOQ== X-Gm-Message-State: AOAM5311M7wAe0OzQTNh+ApaUKLM9zYugJq2vP9FfB0yOXM2vjQ4gugo Bf5Ki3QVPIETm9ux8/HrAVRVr7MURg== X-Google-Smtp-Source: ABdhPJxyooWnERKMMOe817RvnVcNz3HD2yH1iZf7YhESaOMD+6htuNPS+q5rU09UCiBaA5VXRwqxnQ== X-Received: by 2002:a05:6870:e495:: with SMTP id v21mr317265oag.288.1644014237767; Fri, 04 Feb 2022 14:37:17 -0800 (PST) Received: from robh.at.kernel.org (66-90-148-213.dyn.grandenetworks.net. [66.90.148.213]) by smtp.gmail.com with ESMTPSA id h2sm1215234ots.51.2022.02.04.14.37.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Feb 2022 14:37:17 -0800 (PST) Received: (nullmailer pid 3310469 invoked by uid 1000); Fri, 04 Feb 2022 22:37:16 -0000 Date: Fri, 4 Feb 2022 16:37:16 -0600 From: Rob Herring To: Rajeev Nandan Cc: dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, sean@poorly.run, daniel@ffwll.ch, quic_abhinavk@quicinc.com, quic_kalyant@quicinc.com, quic_mkrishn@quicinc.com, linux-arm-msm@vger.kernel.org, airlied@linux.ie, jonathan@marek.ca, dmitry.baryshkov@linaro.org, swboyd@chromium.org, freedreno@lists.freedesktop.org, robh+dt@kernel.org, robdclark@gmail.com Subject: Re: [v5 1/3] dt-bindings: msm/dsi: Add 10nm dsi phy tuning properties Message-ID: References: <1643573719-32095-1-git-send-email-quic_rajeevny@quicinc.com> <1643573719-32095-2-git-send-email-quic_rajeevny@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1643573719-32095-2-git-send-email-quic_rajeevny@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 31 Jan 2022 01:45:17 +0530, Rajeev Nandan wrote: > In most cases, the default values of DSI PHY tuning registers should be > sufficient as they are fully optimized. However, in some cases where > extreme board parasitics cause the eye shape to degrade, the override > bits can be used to improve the signal quality. > > The general guidelines for DSI PHY tuning include: > - High and moderate data rates may benefit from the drive strength and > drive level tuning. > - Drive strength tuning will affect the output impedance and may be used > for matching optimization. > - Drive level tuning will affect the output levels without affecting the > impedance. > > The clock and data lanes have a calibration circuitry feature. The drive > strength tuning can be done by adjusting rescode offset for hstop/hsbot, > and the drive level tuning can be done by adjusting the LDO output level > for the HSTX drive. > > Signed-off-by: Rajeev Nandan > --- > > Changes in v2: > - More details in the commit text (Stephen Boyd) > - Use human understandable values (Stephen Boyd, Dmitry Baryshkov) > - Do not take values that are going to be unused (Dmitry Baryshkov) > > Changes in v3: > - Use "qcom," prefix (Dmitry Baryshkov) > - Remove encoding from phy-drive-ldo-level (Dmitry Baryshkov) > - Use negative values instead of two's complement (Dmitry, Rob Herring) > > Changes in v4: > - Fix dt_binding_check error (Rob Herring's bot) > > Changes in v5: > - None > > .../bindings/display/msm/dsi-phy-10nm.yaml | 36 ++++++++++++++++++++++ > 1 file changed, 36 insertions(+) > Reviewed-by: Rob Herring