From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A2409C6778F for ; Sat, 7 Jul 2018 06:16:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4EE4021CDA for ; Sat, 7 Jul 2018 06:16:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4EE4021CDA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=c-sky.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752018AbeGGGQm (ORCPT ); Sat, 7 Jul 2018 02:16:42 -0400 Received: from smtp2200-217.mail.aliyun.com ([121.197.200.217]:35555 "EHLO smtp2200-217.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750949AbeGGGQl (ORCPT ); Sat, 7 Jul 2018 02:16:41 -0400 X-Alimail-AntiSpam: AC=CONTINUE;BC=0.1416438|-1;CH=green;FP=0|0|0|0|0|-1|-1|-1;HT=e02c03305;MF=ren_guo@c-sky.com;NM=1;PH=DS;RN=12;RT=12;SR=0;TI=SMTPD_---.CNM-2hy_1530944166; Received: from localhost(mailfrom:ren_guo@c-sky.com fp:SMTPD_---.CNM-2hy_1530944166) by smtp.aliyun-inc.com(10.147.40.7); Sat, 07 Jul 2018 14:16:06 +0800 Date: Sat, 7 Jul 2018 14:16:06 +0800 From: Guo Ren To: Mark Rutland Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, daniel.lezcano@linaro.org, jason@lakedaemon.net, arnd@arndb.de, c-sky_gcc_upstream@c-sky.com, gnu-csky@mentor.com, thomas.petazzoni@bootlin.com, wbx@uclibc-ng.org, green.hu@gmail.com Subject: Re: [PATCH V2 16/19] csky: SMP support Message-ID: <20180707061606.GA26276@guoren> References: <21d859826fe19aecaa2aefe3103d6d33e6f1b925.1530465326.git.ren_guo@c-sky.com> <20180706052432.q74gql32dtj5gj3b@salmiak> <20180706113200.GA27148@guoren> <20180706114352.6r7zkjunoafqtr3s@lakrids.cambridge.arm.com> <20180706122631.GA30265@guoren> <20180706162100.3iimik242cied2c6@lakrids.cambridge.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180706162100.3iimik242cied2c6@lakrids.cambridge.arm.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 06, 2018 at 05:21:00PM +0100, Mark Rutland wrote: > Please don't open-code this. Use of_device_is_available(), which checks > the status property itself. e.g. > > void __init setup_smp(void) > { > struct device_node *node = NULL; > > while ((node = of_find_node_by_type(node, "cpu"))) { > if (!of_device_is_available(node)) > continue; > > ... > } > } Ok, approve. > Please use the reg property, you need it to describe which particular > CPUs are available. > > You probably also want a mapping from Linux logical CPU id to your > physical CPU id, and a sanity check on this. See arm64 for an example. Yes, you are right. Reg property could determine which bit of CPU in cr<0, 29> could be booted. Thx for the tips. Guo Ren