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 3099CC43613 for ; Sun, 23 Jun 2019 15:09:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8C1CF20645 for ; Sun, 23 Jun 2019 15:09:24 +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="M3dZBZAT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726653AbfFWPJW (ORCPT ); Sun, 23 Jun 2019 11:09:22 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:50410 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726429AbfFWPJV (ORCPT ); Sun, 23 Jun 2019 11:09:21 -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=DK1nBU1K8tD9huiEBUso9OtrNSNj9E95x9HSnFZclIk=; b=M3dZBZAT7/s2rorVn4rP6NWRlC 2TgYcr7mxF5VScrsdoRIWF30AY2Mn5f/ECLiXRFCx6mzoG4hpXZQc3sUBYkMyTL6tL/BLk48Hn7nB rBkZuZlnSlHlYPnl4xlmdS2DXujJhbfHncT3wvu90mSzctrzknNwiaUCiRgswJtL2zWU=; Received: from andrew by vps0.lunn.ch with local (Exim 4.89) (envelope-from ) id 1hf474-0007rk-5S; Sun, 23 Jun 2019 17:09:02 +0200 Date: Sun, 23 Jun 2019 17:09:02 +0200 From: Andrew Lunn To: Parshuram 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, rafalc@cadence.com, aniljoy@cadence.com, piotrs@cadence.com Subject: Re: [PATCH v4 4/5] net: macb: add support for high speed interface Message-ID: <20190623150902.GB28942@lunn.ch> References: <1561281419-6030-1-git-send-email-pthombar@cadence.com> <1561281806-13991-1-git-send-email-pthombar@cadence.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1561281806-13991-1-git-send-email-pthombar@cadence.com> 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 > +enum { > + HS_MAC_SPEED_100M, > + HS_MAC_SPEED_1000M, > + HS_MAC_SPEED_2500M, > + HS_MAC_SPEED_5000M, > + HS_MAC_SPEED_10000M, > + HS_MAC_SPEED_25000M, > +}; > + > +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. > + if (bp->phy_interface == PHY_INTERFACE_MODE_USXGMII) { > + switch (bp->serdes_rate) { > + case MACB_SERDES_RATE_5_PT_15625Gbps: > + rate = 78125000; > + break; > + case MACB_SERDES_RATE_10_PT_3125Gbps: > + rate = 156250000; > + break; > + default: > + return; > + } Xilinx documentation: https://www.xilinx.com/support/documentation/ip_documentation/usxgmii/v1_1/pg251-usxgmii.pdf seems to suggest USXGMII uses a fixed rate of 10.3125Gb/s. So why do you need to change the rate? Andrew