From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933733AbbLOVJ2 (ORCPT ); Tue, 15 Dec 2015 16:09:28 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:57612 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753527AbbLOVJ0 (ORCPT ); Tue, 15 Dec 2015 16:09:26 -0500 Subject: Re: [PATCH] net: emac: emac gigabit ethernet controller driver To: Arnd Bergmann Cc: Christopher Covington , Florian Fainelli , Gilad Avidov , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org, sdharia@codeaurora.org, shankerd@codeaurora.org, gregkh@linuxfoundation.org, vikrams@codeaurora.org References: <1450138740-32562-1-git-send-email-gavidov@codeaurora.org> <1594472.ixZvj6PYdz@wuerfel> <56702EEC.8000506@codeaurora.org> <1579270.z2ZaCA4LQo@wuerfel> From: Timur Tabi Message-ID: <56708183.4090005@codeaurora.org> Date: Tue, 15 Dec 2015 15:09:23 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:42.0) Gecko/20100101 Firefox/42.0 SeaMonkey/2.39 MIME-Version: 1.0 In-Reply-To: <1579270.z2ZaCA4LQo@wuerfel> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Arnd Bergmann wrote: > If that's in the probe() called from it function, just use writel() everywhere, > a few extra microseconds won't kill the boot time. In general, if a user would > notice the difference, use the relaxed version and add a comment to explain > how you proved it's correct, otherwise stay with the default accessors. What about adding a wmb() after the last writel()? This driver does that a lot. Is that something we want to discourage? I can understand how we would want to make sure that the last write is posted before the function exits.