From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Sune Subject: Re: [PATCH v2 1/2] Added ETH_SPEED_CAP bitmap in rte_eth_dev_info Date: Thu, 18 Jun 2015 17:06:44 +0200 Message-ID: <5582DE84.5040702@bisdn.de> References: <98CBD80474FA8B44BF855DF32C47DC358AF172@smartserver.smartshare.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: quoted-printable To: dev@dpdk.org, Thomas Monjalon Return-path: Received: from mx.bisdn.de (mx.bisdn.de [185.27.182.31]) by dpdk.org (Postfix) with ESMTP id E30DBC3E6 for ; Thu, 18 Jun 2015 17:06:45 +0200 (CEST) In-Reply-To: <98CBD80474FA8B44BF855DF32C47DC358AF172@smartserver.smartshare.dk> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 18/06/15 16:43, Morten Br=F8rup wrote: > Regarding the PHY speed ABI: > > =20 > > 1. The Ethernet PHY ABI for speed, duplex, etc. should be common throug= hout the entire DPDK. It might be confusing if some structures/functions = use a bitmask to indicate PHY speed/duplex/personality/etc. and other str= uctures/functions use a combination of an unsigned integer, duplex flag, = personality enumeration etc. (By personality enumeration, I am referring = to PHYs with multiple electrical interfaces. E.g. a dual personality PHY = might have both an RJ45 copper interface and an SFP module interface, whe= reof only one can be active at any time.) Thomas was sending a similar comment and I agreed to do a unified speed=20 bitmap for both capabilities and link negotiation/link info (v3, waiting=20 for 2.2 merge window): http://dpdk.org/ml/archives/dev/2015-June/019207.html > > =20 > > 2. The auto-negotiation standard allows the PHY to announce (to its lin= k partner) any subset of its capabilities to its link partner. E.g. a sta= ndard 10/100/100 Ethernet PHY (which can handle both 10 and 100 Mbit/s in= both half and full duplex and 1 Gbit/s full duplex) can be configured to= announce 10 Mbit/s half duplex and 100 Mbit/s full duplex capabilities t= o its link partner. (Of course, more useful combinations are normally ann= ounced, but the purpose of the example is to show that any combination is= possible.) > > =20 > > The ABI for auto-negotiation should include options to select the list = of capabilities to announce to the link partner. The Linux PHY ABI only a= llows forcing a selected speed and duplex (thereby disabling auto-negotia= tion) or enabling auto-negotiation (thereby announcing all possible speed= s and duplex combinations the PHY is capable of). Don't make the same mis= take in DPDK. I see what you mean, and you are probably right. In any case this is for=20 a separate patch, if we think it is a necessary feature to implement. Nevertheless, this makes me rethink about the proposal from Thomas about=20 unifying _100_HD/_100_FD to 100M, because you will need this=20 granularity, eventually. @Thomas: opinions? Thanks Marc p.s. Please configure your email client to reply using "In-Reply-To:" to=20 allow clients and ML archives to use threading. > =20 > > PS: While working for Vitesse Semiconductors (an Ethernet chip company)= a long time ago, I actually wrote the API for their line of Ethernet PHY= s. So I have hands on experience in this area. > > =20 > > =20 > > Med venlig hilsen / kind regards > > =20 > > Morten Br=F8rup > > CTO > > =20 > > =20 > > =20 > > SmartShare Systems A/S > > Tonsbakken 16-18 > > DK-2740 Skovlunde > > Denmark > > =20 > > Office +45 70 20 00 93 > > Direct +45 89 93 50 22 > > Mobile +45 25 40 82 12 > > =20 > > mb@smartsharesystems.com > > www.smartsharesystems.com > > =20 >