From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-m49208.qiye.163.com (mail-m49208.qiye.163.com [45.254.49.208]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DC68433EB06; Thu, 22 Jan 2026 07:27:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.254.49.208 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769066837; cv=none; b=uVMDPh0NrVYWApqDN9KcdXG1CnF39nZPsUtBBUN0PtcqUMrFTazkDOGoPGyfM4GRcPGEuWVGJosVOW4eIjEPaC2t5+tQOXaW0wJ2aDLwOk+ZkH8Q5pFRMb5C6laZimjnziUksLdDzTyC+y1PUY+C92d29P5r22vp57hduReeb9A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769066837; c=relaxed/simple; bh=e+HGaijuNfShAZ24U1rDRUxjbly2NpM3NgkOMJprROk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=JVIPwdymHx0J/gRnXYJIzha7AYKdvtjj7or/dwbMczDa4R6I9T6yBWs6p54fA5Z16T7tRXBo2DDXHczGYYQzlJBWSGn8/BMkflCtWIy68gtHM13jfl27pvlx1rU3I0bJdVXZlZOHN6lbV0oy0pN7JZT2FDt28L7XNHvcI39G+AU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com; spf=pass smtp.mailfrom=rock-chips.com; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b=e/1/N/h6; arc=none smtp.client-ip=45.254.49.208 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b="e/1/N/h6" Received: from [127.0.0.1] (unknown [58.22.7.114]) by smtp.qiye.163.com (Hmail) with ESMTP id 318437bb3; Thu, 22 Jan 2026 09:44:11 +0800 (GMT+08:00) Message-ID: Date: Thu, 22 Jan 2026 09:44:10 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/3] arm64: dts: rockchip: Change gmac phy-mode to rgmii-id for rk3576 board To: Andrew Lunn , Chaoyi Chen Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Heiko Stuebner , Alexey Charkov , Shawn Lin , Sebastian Reichel , Andy Yan , Nicolas Frattaroli , Detlev Casanova , Stephen Chen , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org References: <20260121031548.402-1-kernel@airkyi.com> Content-Language: en-US From: Chaoyi Chen In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-HM-Tid: 0a9be35f986103abkunm2cc02e0dab60f X-HM-MType: 1 X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFDSUNOT01LS0k3V1ktWUFJV1kPCRoVCBIfWUFZGk8fSVZCSx5CSU0ZTktMSEhWFRQJFh oXVRMBExYaEhckFA4PWVdZGBILWUFZTkNVSUlVTFVKSk9ZV1kWGg8SFR0UWUFZT0tIVUpLSU9PT0 hVSktLVUpCS0tZBg++ DKIM-Signature: a=rsa-sha256; b=e/1/N/h6wrnqA7VHwQI73Bv34Hxa4/97ZmtUIfQ98i+pN998XA6ELUU5l3UrHj0OtN2BVxucSQZnHneR/br2JWwSE3OPwK/ati9o9WrghKL5I6wF94M0lxfFLcSQGYTLNIWk/7d2Rk3YzVRq4Md5rNnxD8qN8B2H+YLJjd2afoM=; c=relaxed/relaxed; s=default; d=rock-chips.com; v=1; bh=xepetMOANOmDjgKxqlDl2/kYrljTtdNa/MYCm6NNH4g=; h=date:mime-version:subject:message-id:from; Hi Andrew, On 1/21/2026 8:57 PM, Andrew Lunn wrote: > On Wed, Jan 21, 2026 at 11:15:45AM +0800, Chaoyi Chen wrote: >> From: Chaoyi Chen >> >> According to the description in the net documentation, PHY modes >> "rgmii", "rgmii-rxid" and "rgmii-txid" modes require the clock signal >> to be delayed on the PCB. >> >> The Rockchip platform has long used the above mentioned PHY modes and >> private delay prop to describe the internal IO delay settings of the >> chip, which is inconsistent with what is described in the documentation. >> >> Some background, for RK3576, you can assume that: >> >> tx_delay_time(ns) = 0.0579 * delay_line_count + 0.105 > > Where did this formula come from? Is it in the datasheet. > These are measured values obtained from hardware signal testing. They are not documented in the TRM. -- Best, Chaoyi