From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by dpdk.org (Postfix) with ESMTP id 4FE962C71 for ; Wed, 8 Mar 2017 15:17:02 +0100 (CET) Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Mar 2017 06:17:01 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,264,1486454400"; d="scan'208";a="74241579" Received: from bricha3-mobl3.ger.corp.intel.com ([10.237.221.61]) by fmsmga006.fm.intel.com with SMTP; 08 Mar 2017 06:16:59 -0800 Received: by (sSMTP sendmail emulation); Wed, 08 Mar 2017 14:16:58 +0000 Date: Wed, 8 Mar 2017 14:16:58 +0000 From: Bruce Richardson To: raman geetha gopalakrishnan Cc: dev@dpdk.org Message-ID: <20170308141658.GA292076@bricha3-MOBL3.ger.corp.intel.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Research and =?iso-8859-1?Q?De=ACvel?= =?iso-8859-1?Q?opment?= Ireland Ltd. User-Agent: Mutt/1.8.0 (2017-02-23) Subject: Re: [dpdk-dev] Reg DPDK & PMD X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 Mar 2017 14:17:02 -0000 On Wed, Mar 08, 2017 at 07:05:03PM +0530, raman geetha gopalakrishnan wrote: > Hi All, > > I have the following basic question. Hope to get an answer / link where i > can get myself clear. > > 1. In DPDK PMD is optimized driver for an given NIC to get maximum > performance. > That being the case why we are talking about DPDK supported NICs. > > A) My assumption is that NIC interface is standardized so that PMD > should actually work with any NIC (barring some NIC specific performance > tweaks) > is that correct? No, that assumption is not correct, which is the reason we have so many NIC drivers in DPDK. Each NIC uses a different method of talking to SW, both in terms of the registers needed to be accessed to initialize the NIC and then in terms of the metadata format used to receive or transmit packets. Regards, /Bruce > > B) if #A is correct , how can i make changes to PMD to support any NIC > ? > > if i have to put the above question in different way then it is > > 2. what is preventing us from having a common PMD layer for all NICs and > additional PMD specific to each NIC??? > > Thanks > Raman