From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Lunn Subject: Re: [PATCH v2 net-next 0/2] net: phy: Add Edge-rate, MAC-IF driver for Microsemi PHYs Date: Thu, 8 Sep 2016 14:59:58 +0200 Message-ID: <20160908125958.GF26445@lunn.ch> References: <20160824125934.GC13406@lunn.ch> <1473326242-4198-1-git-send-email-Raju.Lakkaraju@microsemi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, f.fainelli@gmail.com, Allan.Nielsen@microsemi.com To: Raju Lakkaraju Return-path: Received: from vps0.lunn.ch ([178.209.37.122]:38812 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934510AbcIHNAA (ORCPT ); Thu, 8 Sep 2016 09:00:00 -0400 Content-Disposition: inline In-Reply-To: <1473326242-4198-1-git-send-email-Raju.Lakkaraju@microsemi.com> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Sep 08, 2016 at 02:47:20PM +0530, Raju Lakkaraju wrote: > Patch 1/2: > > This is Edge rate control feature. > As system and networking speeds increase, a signal's output transition, > also know as the edge rate or slew rate (V/ns), takes on greater importance > because high-speed signals come with a price. That price is an assortment of > interference problems like ringing on the line, signal overshoot and > undershoot, extended signal settling times, crosstalk noise, transmission line > reflections, false signal detection by the receiving device and electromagnetic > interference (EMI) -- all of which can negate the potential gains designers are > seeking when they try to increase system speeds through the use of higher > performance logic devices. The fact is, faster signaling edge rates can cause > a higher level of electrical noise or other type of interference that can > actually lead to slower line speeds and lower maximum system frequencies. > > Microsemi PHY have the provision to configure the edge rate. Edge-rate function > program the right value based on Device Tree configuration. > > Tested on Beaglebone Black with VSC 8531 PHY. > > Patch 2/2: > > This is MAC interface feature. > Microsemi PHY can support RGMII, RMII or GMII/MII interface between MAC and PHY. > MAC-IF function program the right value based on Device tree configuration. Hi Raju In future, please start a new thread for a new version of the patchset. Thanks Andrew