From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [RFC 2/2] ethtool: Add support for DMA Coalescing feature config to ethtool. Date: Fri, 17 Jun 2011 14:54:20 -0400 (EDT) Message-ID: <20110617.145420.866989290749857501.davem@davemloft.net> References: <1308071606-6333-1-git-send-email-carolyn.wyborny@intel.com> <20110616.233354.508986372720173787.davem@davemloft.net> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, bhutchings@solarflare.com To: carolyn.wyborny@intel.com Return-path: Received: from shards.monkeyblade.net ([198.137.202.13]:56168 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751880Ab1FQSy0 (ORCPT ); Fri, 17 Jun 2011 14:54:26 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: From: "Wyborny, Carolyn" Date: Fri, 17 Jun 2011 08:50:11 -0700 > I will add a fuller description of the feature in my updated patch. > I thought the feature was more well known. Quick description is that > it's a power saving feature that causes the adapter to coalesce its > DMA writes at low traffic times to save power on the platform by > reducing wakeups. The parameter is intended as a simple u32 value, > not just an on or off, but also to allow a variety of configuration > by adapter vendors, with validation of the input on the driver side. > Since I left out the implementation in my patch, this wasn't clear. > I will also fix this in my next submission. The value cannot have adapter specific meaning, you must define it precisely and in a generic manner, such that the user can specify the same setting across different card types.