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=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 7655FC433E1 for ; Wed, 20 May 2020 16:03:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 54BB320759 for ; Wed, 20 May 2020 16:03:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="tqYfNJBq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726943AbgETQDz (ORCPT ); Wed, 20 May 2020 12:03:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726596AbgETQDz (ORCPT ); Wed, 20 May 2020 12:03:55 -0400 Received: from mail-pg1-x544.google.com (mail-pg1-x544.google.com [IPv6:2607:f8b0:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6BE56C061A0E; Wed, 20 May 2020 09:03:55 -0700 (PDT) Received: by mail-pg1-x544.google.com with SMTP id d10so1640823pgn.4; Wed, 20 May 2020 09:03:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=OOwuxWEO/Sl8yx5TsqcCpHvO91TmRIyEZirMBX+Uvb0=; b=tqYfNJBqFCzIdnyTQnESaY2EhitXzArebVnBxAmiWUH31YSwGkyxGT0bxmjdCnNP3I doqAT4kPg0MYs4+BiQ1Z3U1ofhnEK7ta3Pg1xLEAVVEBIzepp2mPu65oNVqpTA9bQB8b BH5ZCfTfUNCJzdtBjLYpmc20KA7BhcXfs8NywHaFaxxnayfjpnQLC9neSD3GFyRNHM89 NCu07RBOShh6FI8LU3twTebMt0uAnwfJJTbpsKJHe1sUBcZIRdUKl5PcTpo7c2QFxqZZ QO2rjpg22xaV7mFRc5Iowj9Z6nkp2FIIOKvZ947SgpukLUqvIo+PwalmnOLcrrr6llAB P0Fw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=OOwuxWEO/Sl8yx5TsqcCpHvO91TmRIyEZirMBX+Uvb0=; b=T18iy+PF1ETZQ8uWvFNV2KApObosuFGblXWl9pA8/LSOI4sySzDQpaBHONwST/fvo9 lkENUP2EJ2WuvctEtYo/EHNZVuoXqdg3aCjnWc4zEgVE2C4M5YpPCbh4w4FmtEpR8CoD VpErf4N+rba5ef9D0AUeKZDHfObWIzkGyUYBerQI/hBVsgrCyctLq6v1NCFYMSFw3y7N k+CX/ZcL/btsFE9hQxpS1VCVUojq6wy7S80Kpdq3akLOp6FhaolEV0oNJc00TYO0WmfG h66YhiO33gVgzhmZ9I3cdthVZzzX6SocQX/QKbgbZggy5biJpyIvuspTaaM6gLO8lnzl vsQA== X-Gm-Message-State: AOAM53257m8vzqvYKfvZD91iF8EKUGMNthUgOYTb1VMKDBFGatFa4EJn 3JYAHb4s2j1pGSql+tw7nqMru/sL X-Google-Smtp-Source: ABdhPJyzKgk4okw2I5EAYp6yP9oqV+jg1QwGBzglmgRe4hDbyE6yihw912kZx/Hr1COTy0fgNciqFw== X-Received: by 2002:a63:2347:: with SMTP id u7mr4590793pgm.183.1589990634413; Wed, 20 May 2020 09:03:54 -0700 (PDT) Received: from [10.230.188.43] ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id w7sm2381841pfw.82.2020.05.20.09.03.52 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 20 May 2020 09:03:53 -0700 (PDT) Subject: Re: [PATCH net-next v2 3/4] dt-bindings: net: Add RGMII internal delay for DP83869 To: Dan Murphy , Andrew Lunn Cc: hkallweit1@gmail.com, davem@davemloft.net, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org References: <20200520121835.31190-1-dmurphy@ti.com> <20200520121835.31190-4-dmurphy@ti.com> <20200520135624.GC652285@lunn.ch> <770e42bb-a5d7-fb3e-3fc1-b6f97a9aeb83@ti.com> <20200520153631.GH652285@lunn.ch> <95ab99bf-2fb5-c092-ad14-1b0a47c782a4@ti.com> From: Florian Fainelli Message-ID: <0d80a7f6-35a9-9b3f-2a8f-65b793d1ce98@gmail.com> Date: Wed, 20 May 2020 09:03:52 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Firefox/68.0 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <95ab99bf-2fb5-c092-ad14-1b0a47c782a4@ti.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/20/2020 8:56 AM, Dan Murphy wrote: > Andrew > > On 5/20/20 10:36 AM, Andrew Lunn wrote: >>>> Hi Dan >>>> >>>> Having it required with PHY_INTERFACE_MODE_RGMII_ID or >>>> PHY_INTERFACE_MODE_RGMII_RXID is pretty unusual. Normally these >>>> properties are used to fine tune the delay, if the default of 2ns does >>>> not work. >>> Also if the MAC phy-mode is configured with RGMII-ID and no internal >>> delay >>> values defined wouldn't that be counter intuitive? >> Most PHYs don't allow the delay to be fine tuned. You just pass for >> example PHY_INTERFACE_MODE_RGMII_ID to the PHY driver and it enables a >> 2ns delay. That is what people expect, and is documented. > >> Being able to tune the delay is an optional extra, which some PHYs >> support, but that is always above and beyond >> PHY_INTERFACE_MODE_RGMII_ID. > > I am interested in knowing where that is documented.  I want to RTM I > grepped for a few different words but came up empty > > Since this is a tuneable phy we need to program the ID.  2ns is the > default value > > Maybe I can change it from Required to Configurable or Used. I do not think this is properly documented, it is an established practice, but it should be clearly documented somewhere, I do not know whether that belongs in the PHY Device Tree binding or if this belongs to the PHY documentation. -- Florian