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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT autolearn=ham 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 7F7F6C004D3 for ; Mon, 22 Oct 2018 18:19:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2746720645 for ; Mon, 22 Oct 2018 18:19:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="vFQI9JLm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2746720645 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lunn.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728948AbeJWCjI (ORCPT ); Mon, 22 Oct 2018 22:39:08 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:40462 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727820AbeJWCjH (ORCPT ); Mon, 22 Oct 2018 22:39:07 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date; bh=X2MjUn5SdTxwbjQ7NS4UuOUNhjuzvI6CH3UTbd6MP5Q=; b=vFQI9JLmGhAV7soC++/8Io3SdVaal+DHRZjLnWCYaxjjY29RT3oGYknoIfbBO56vLxeNCn+Dvoxt97dH8IoIAqBb6Y4fXi5hilzzMh3qkaRbuVvyQ2Rd1UWEYIGKDboJ5YjmzQcb+7Bx/Bgrz6xalO5YCRG2gTrODWaQvz/2U84=; Received: from andrew by vps0.lunn.ch with local (Exim 4.84_2) (envelope-from ) id 1gEenO-0000bB-8o; Mon, 22 Oct 2018 20:19:18 +0200 Date: Mon, 22 Oct 2018 20:19:18 +0200 From: Andrew Lunn To: Richard Genoud Cc: Willy Tarreau , linux-kernel@vger.kernel.org, Thomas Petazzoni , Antoine Tenart , Gregory CLEMENT , Yelena Krivosheev , Maxime Chevallier , Nicolas Ferre , netdev@vger.kernel.org Subject: Re: CRC errors between mvneta and macb Message-ID: <20181022181918.GF24112@lunn.ch> References: <20181019154439.GC24045@1wt.eu> <31385a3b-2196-94d0-7f4f-52e37ee07a28@sorico.fr> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <31385a3b-2196-94d0-7f4f-52e37ee07a28@sorico.fr> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > I dug more on the subject, and I think I found what Marvell's PHY/MAC > doesn't like. Hi Richard What PHY is being used? > After analyzing the ethernet frame on the Davicom PHY's output (pin > TX+), I find out that the FCS errors occurs when the ethernet preamble > is longer than 56bits. (something like 58 or 60 bits) Some Marvell PHYs have a register bit which might be of interest: Page 2, register 16, bit 6. 0 = Pad odd nibble preambles in copper receive packets. 1 = Pass as is and do not pad odd nibble preambles in Andrew