Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755749AbbGTIpD (ORCPT ); Mon, 20 Jul 2015 04:45:03 -0400 Received: from nasmtp01.atmel.com ([192.199.1.245]:21493 "EHLO DVREDG01.corp.atmel.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754500AbbGTIpA (ORCPT ); Mon, 20 Jul 2015 04:45:00 -0400 Message-ID: <55ACB506.9080505@atmel.com> Date: Mon, 20 Jul 2015 16:44:54 +0800 From: Josh Wu User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Maxime Ripard CC: Nicolas Ferre , Alexandre Belloni , , Guenter Roeck , Wei Yongjun , Ben Dooks , , "Krzysztof Kozlowski" , Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse , Fabian Frederick , Subject: Re: [PATCH 1/2] power: reset: at91: add sama5d3 reset function 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> <55ACB2C9.5070701@atmel.com> In-Reply-To: <55ACB2C9.5070701@atmel.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.168.5.13] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3433 Lines: 92 On 7/20/2015 4:35 PM, Josh Wu wrote: > 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 ?crit : >>>>> 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 >>>>>>> function 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 at91 >>>>>> drivers. I'd like to keep it that way. It was painful enough to >>>>>> remove >>>>>> all those cpu_is_at91xxx calls. >>>>> That's your call... >>>>> >>>>>> Also, using it is trying to match strings and will result in >>>>>> longer 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 != >>> 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 > same as of_match_node()/of_match_device(). Except that > of_device_is_compatible() is more efficient (in this case It calls > __of_device_is_compatible() directly) than of_match_node/of_match_device. Sorry, after checking the code a little, I'd say use the of_match_node instead of of_device_is_compatible() is better. Since After check the of_device_is_compatible() we also need to call of_match_node() again. So the simplest way is just get the match data by of_match_node() first, then check the match->data. like following: match = of_match_node(at91_reset_of_match, pdev->dev.of_node); if (match->data != sama5d3_restart) { /* we need to shutdown the ddr controller, so get ramc base */ for_each_matching_node(np, at91_ramc_of_match) { at91_ramc_base[idx] = of_iomap(np, 0); if (!at91_ramc_base[idx]) { dev_err(&pdev->dev, "Could not map ram controller address\n"); return -ENODEV; } idx++; } } at91_restart_nb.notifier_call = match->data; Best Regards, Josh Wu > >> >> - 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/