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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=unavailable 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 BFEA8C43613 for ; Mon, 24 Jun 2019 13:13:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9920F204EC for ; Mon, 24 Jun 2019 13:13:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="39ByeK7q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730740AbfFXNNR (ORCPT ); Mon, 24 Jun 2019 09:13:17 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:53004 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727065AbfFXNNR (ORCPT ); Mon, 24 Jun 2019 09:13:17 -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:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=w71H7qbKzheuPjLTSksNNI0MO2TJKsefOHajDzNwZgs=; b=39ByeK7qX2ak7a7iM7z8+DWROE KFDEQzjJaWASnQiIZ2oZU7hW5oKBH3vw5ic18SbPnO8IpKNSZ8JhOGkJAXtSIoJxj+hqb9Z+2XP6t ZSwePeCn44vuBv9RYayRq4GJ5odIldzQZZiA9G4KqoN7/QaexM0h6H9yh0XchlMfXkME=; Received: from andrew by vps0.lunn.ch with local (Exim 4.89) (envelope-from ) id 1hfOmR-0004ll-Ta; Mon, 24 Jun 2019 15:13:07 +0200 Date: Mon, 24 Jun 2019 15:13:07 +0200 From: Andrew Lunn To: Parshuram Raju Thombare Cc: "nicolas.ferre@microchip.com" , "davem@davemloft.net" , "f.fainelli@gmail.com" , "linux@armlinux.org.uk" , "netdev@vger.kernel.org" , "hkallweit1@gmail.com" , "linux-kernel@vger.kernel.org" , Rafal Ciepiela , Anil Joy Varughese , Piotr Sroka Subject: Re: [PATCH v4 4/5] net: macb: add support for high speed interface Message-ID: <20190624131307.GA17872@lunn.ch> References: <1561281419-6030-1-git-send-email-pthombar@cadence.com> <1561281806-13991-1-git-send-email-pthombar@cadence.com> <20190623150902.GB28942@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Jun 24, 2019 at 06:52:51AM +0000, Parshuram Raju Thombare wrote: > Hi Andrew, > > >> +enum { > >> + MACB_SERDES_RATE_5_PT_15625Gbps = 5, > >> + MACB_SERDES_RATE_10_PT_3125Gbps = 10, > >> +}; > >What do the units mean here? Why would you clock the SERDES at 15Tbps, > >or 3Tbps? 3.125Mbps would give you 2.5Gbps when using 8b/10b encoding. > > > MACB_SERDES_RATE_5_PT_15625Gbps is for 5.15625Gbps, I think this should be just > MACB_SERDES_RATE_5_Gbps and MACB_SERDES_RATE_10_Gbps. I will do it in next patch set. OK. > >Xilinx documentation: > >https://urldefense.proofpoint.com/v2/url?u=https- > >3A__www.xilinx.com_support_documentation_ip-5Fdocumentation_usxgmii_v1- > >5F1_pg251- > >2Dusxgmii.pdf&d=DwIBAg&c=aUq983L2pue2FqKFoP6PGHMJQyoJ7kl3s3GZ- > >_haXqY&r=GTefrem3hiBCnsjCOqAuapQHRN8-rKC1FRbk0it- > >LDs&m=6V8fNIg49czRjfvVtDJ5BbR28p9UPlLLyB7fah7ypcw&s=LsDphgLBe1VDpM > >_K9pkuyal873WeKqHDv64NDRUWy1Q&e= > >seems to suggest USXGMII uses a fixed rate of 10.3125Gb/s. So why do > >you need to change the rate? > For USXGMII, Cadence MAC need to be correctly programmed for external serdes rate. What i'm saying is that the USXGMII rate is fixed. So why do you need a device tree property for the SERDES rate? Andrew