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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 94960C2D0EC for ; Fri, 27 Mar 2020 15:45:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6B00A20936 for ; Fri, 27 Mar 2020 15:45:05 +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="bPPkVIFb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727393AbgC0PpD (ORCPT ); Fri, 27 Mar 2020 11:45:03 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:34284 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726515AbgC0PpD (ORCPT ); Fri, 27 Mar 2020 11:45:03 -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=Pm/asNb1Pns7utlRhHbrECwkl0DqjgsSY9mzrFMWbfc=; b=bPPkVIFbYibgLevFJDBOJPj9z8 vLZPFE4CZqVSOcg9UstAwQmVVhdcjPIkgLkeDbZiXK3wfVC9q4l/VkbVHndf0uxEA4l3lmnhvUTa6 pExzEGX0D5qVstXT3yGsZR0Am0t+PtD7PgcCmE+JQHMW7IQuXkJ3EDqm2dN1R+y6Kb/M=; Received: from andrew by vps0.lunn.ch with local (Exim 4.93) (envelope-from ) id 1jHrA8-0002qY-2y; Fri, 27 Mar 2020 16:44:48 +0100 Date: Fri, 27 Mar 2020 16:44:48 +0100 From: Andrew Lunn To: Russell King - ARM Linux admin Cc: Florinel Iordache , "davem@davemloft.net" , "netdev@vger.kernel.org" , "f.fainelli@gmail.com" , "hkallweit1@gmail.com" , "devicetree@vger.kernel.org" , "linux-doc@vger.kernel.org" , "robh+dt@kernel.org" , "mark.rutland@arm.com" , "kuba@kernel.org" , "corbet@lwn.net" , "shawnguo@kernel.org" , Leo Li , "Madalin Bucur (OSS)" , Ioana Ciornei , "linux-kernel@vger.kernel.org" Subject: Re: [EXT] Re: [PATCH net-next 2/9] dt-bindings: net: add backplane dt bindings Message-ID: <20200327154448.GK11004@lunn.ch> References: <1585230682-24417-1-git-send-email-florinel.iordache@nxp.com> <1585230682-24417-3-git-send-email-florinel.iordache@nxp.com> <20200327010411.GM3819@lunn.ch> <20200327152849.GP25745@shell.armlinux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200327152849.GP25745@shell.armlinux.org.uk> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org > What worries me is the situation which I've been working on, where > we want access to the PCS PHYs, and we can't have the PCS PHYs > represented as a phylib PHY because we may have a copper PHY behind > the PCS PHY, and we want to be talking to the copper PHY in the > first instance (the PCS PHY effectivel ybecomes a slave to the > copper PHY.) I guess we need to clarify what KR actually means. If we have a backplane with a MAC on each end, i think modelling it as a PHY could work. If however, we have a MAC connected to a backplane, and on the end of the backplane is a traditional PHY, or an SFP cage, we have problems. As your point out, we cannot have two PHYs in a chain for one MAC. But i agree with Russell. We need a general solution of how we deal with PCSs. Andrew