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=-5.8 required=3.0 tests=BAYES_00,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 7969AC49361 for ; Sun, 13 Jun 2021 16:31:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60879610FB for ; Sun, 13 Jun 2021 16:31:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231984AbhFMQd6 (ORCPT ); Sun, 13 Jun 2021 12:33:58 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:33660 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231915AbhFMQd4 (ORCPT ); Sun, 13 Jun 2021 12:33:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Transfer-Encoding:Content-Disposition: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:From: Sender:Reply-To:Subject:Date:Message-ID:To:Cc:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Content-Disposition: In-Reply-To:References; bh=Rfpd3/bKKCNWwkSNXhRu75K3KXs2S+zGTIfGuFswvLs=; b=Mj gvFaDw3lND4PyN5ThRZiMAoB5uVhB8oTRYdmQeDsMwhF3KyM2kqkeBIwVSAxR3XUA01KZ9BLPz2fn dLKNsN7NN2rWKswvyPjZuuoisztG4KxMa/3s/sqhpF2C+Utc0c7z0ED94Cud5rML6G7k9WNdgxPBZ 1SfGlSYoF/AC9/E=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1lsT1M-009B5K-CB; Sun, 13 Jun 2021 18:31:36 +0200 Date: Sun, 13 Jun 2021 18:31:36 +0200 From: Andrew Lunn To: =?utf-8?B?5ZGo55Cw5p2w?= Cc: davem@davemloft.net, kuba@kernel.org, robh+dt@kernel.org, peppe.cavallaro@st.com, alexandre.torgue@foss.st.com, joabreu@synopsys.com, mcoquelin.stm32@gmail.com, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, dongsheng.qiu@ingenic.com, aric.pzqi@ingenic.com, rick.tyliu@ingenic.com, sihui.liu@ingenic.com, jun.jiang@ingenic.com, sernia.zhou@foxmail.com, paul@crapouillou.net Subject: Re: [PATCH v2 2/2] net: stmmac: Add Ingenic SoCs MAC support. Message-ID: References: <1623260110-25842-1-git-send-email-zhouyanjie@wanyeetech.com> <1623260110-25842-3-git-send-email-zhouyanjie@wanyeetech.com> <405696cb-5987-0e56-87f8-5a1443eadc19@wanyeetech.com> <346f64d9-6949-b506-258f-4cfa7eb22784@wanyeetech.com> <12f35415-532e-5514-bc97-683fb9655091@wanyeetech.com> <20210613163452.1f01d418@zhouyanjie-virtual-machine> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210613163452.1f01d418@zhouyanjie-virtual-machine> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sun, Jun 13, 2021 at 04:34:52PM +0800, 周琰杰 wrote: > 于 Thu, 10 Jun 2021 16:57:29 +0200 > Andrew Lunn 写道: > > > > Here is Ingenic's reply, the time length corresponding to a unit is > > > 19.5ps (19500fs). > > > > Sometimes, there is a negative offset in the delays. So a delay value > > of 0 written to the register actually means -200ps or something. > > Ah, perhaps this explains why we still need to add fine-tuning > parameter in rgmii-id and rgmii-txid modes to ensure that the network > works properly. Please try to find this out. rgmii means no delay. If the hardware is doing -500pS by default, you need to take this into account, and add the 500pS back on. Andrew