From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Wu Subject: Re: [PATCH 1/2] power: reset: at91: add sama5d3 reset function Date: Mon, 20 Jul 2015 16:35:21 +0800 Message-ID: <55ACB2C9.5070701@atmel.com> References: <1436436947-11210-1-git-send-email-josh.wu@atmel.com> <20150710060350.GA3127@piout.net> <559F7AC4.6050008@atmel.com> <20150710120907.GC3127@piout.net> <20150710123148.GA28632@lukather> <559FEED3.5080505@atmel.com> <55A32EC8.4080309@atmel.com> <20150720075231.GQ28632@lukather> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from eusmtp01.atmel.com ([212.144.249.243]:39304 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932295AbbGTIfc (ORCPT ); Mon, 20 Jul 2015 04:35:32 -0400 In-Reply-To: <20150720075231.GQ28632@lukather> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Maxime Ripard Cc: Nicolas Ferre , Alexandre Belloni , linux-arm-kernel@lists.infradead.org, Guenter Roeck , Wei Yongjun , Ben Dooks , linux-kernel@vger.kernel.org, Krzysztof Kozlowski , Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse , Fabian Frederick , linux-pm@vger.kernel.org Hi, Maxime On 7/20/2015 3:52 PM, Maxime Ripard wrote: > Hi Josh, > > On Mon, Jul 13, 2015 at 11:21:44AM +0800, Josh Wu wrote: >> On 7/11/2015 12:12 AM, Nicolas Ferre wrote: >>> Le 10/07/2015 14:31, Maxime Ripard a =E9crit : >>>> On Fri, Jul 10, 2015 at 02:09:07PM +0200, Alexandre Belloni wrote: >>>>> Hi, >>>>> >>>>> On 10/07/2015 at 15:56:52 +0800, Josh Wu wrote : >>>>>> I would agree with Maxime. Currently all latest chip reset funct= ion is >>>>>> compatible with the atmel,sama5d3-rstc. >>>>>> So check compatible string is enough for now. >>>>>> But of cause if we have other incompatible reset in future with = new chip, >>>>>> the structure like you said is needed. >>>>> We managed to avoid using of_machine_is_compatible() in all the a= t91 >>>>> drivers. I'd like to keep it that way. It was painful enough to r= emove >>>>> all those cpu_is_at91xxx calls. >>>> That's your call... >>>> >>>>> Also, using it is trying to match strings and will result in long= er boot >>>>> times. >>>> Have you looked at the implementation of of_match_device? If that'= s >>>> really a concern to you, you should actually avoid it. >>> I agree: let's keep it simple and use of_match_device(). >> Ok. I will keep it as it is now: use the (match->data !=3D sama5d3_= restart) >> for the condition. > I'm not just that's been an option in our discussion so far. > > Nicolas said that he was agreeing with me, but at the same time said > the complete opposite of what I was arguing for, so I'm not really > sure what's really on his mind, but the two options that were > discussed were to remove that test, and either: > > - Use of_device_is_compatible to prevent the loop execution Thank you for explaining, it is clear to me. I'll take this above option. As the of_device_is_compatible() almost=20 same as of_match_node()/of_match_device(). Except that=20 of_device_is_compatible() is more efficient (in this case It calls=20 __of_device_is_compatible() directly) than of_match_node/of_match_devic= e. > > - define a structure with a flag to say whether you need the ram > controller quirk or not, and test that flag. > > Maxime > Best Regards, Josh Wu