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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_SANE_1 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 EFA7BC18E19 for ; Tue, 19 Jan 2021 11:39:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C875B221E5 for ; Tue, 19 Jan 2021 11:39:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391572AbhASLgR (ORCPT ); Tue, 19 Jan 2021 06:36:17 -0500 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:55327 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405637AbhASL2O (ORCPT ); Tue, 19 Jan 2021 06:28:14 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R971e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04426;MF=zhangliguang@linux.alibaba.com;NM=1;PH=DS;RN=10;SR=0;TI=SMTPD_---0UMEykKZ_1611055592; Received: from 30.225.36.0(mailfrom:zhangliguang@linux.alibaba.com fp:SMTPD_---0UMEykKZ_1611055592) by smtp.aliyun-inc.com(127.0.0.1); Tue, 19 Jan 2021 19:26:32 +0800 Subject: Re: [PATCH] arm64/cpuinfo: Show right CPU architecture information To: Will Deacon Cc: Catalin Marinas , Anshuman Khandual , Suzuki K Poulose , Mark Brown , gustavoars@kernel.org, Vincenzo Frascino , Dave Martin , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20210119105510.27836-1-zhangliguang@linux.alibaba.com> <20210119110131.GA18433@willie-the-truck> From: =?UTF-8?B?5Lmx55+z?= Message-ID: Date: Tue, 19 Jan 2021 19:26:31 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: <20210119110131.GA18433@willie-the-truck> Content-Type: text/plain; charset=gbk; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ÔÚ 2021/1/19 19:01, Will Deacon дµÀ: > On Tue, Jan 19, 2021 at 06:55:10PM +0800, Liguang Zhang wrote: >> CPU architecture is assigned to be a fixed value, it should be obtained >> from midr register. >> >> Signed-off-by: Liguang Zhang >> --- >> arch/arm64/kernel/cpuinfo.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c >> index 77605aec25fe..0bd11e0fe9f2 100644 >> --- a/arch/arm64/kernel/cpuinfo.c >> +++ b/arch/arm64/kernel/cpuinfo.c >> @@ -191,7 +191,7 @@ static int c_show(struct seq_file *m, void *v) >> >> seq_printf(m, "CPU implementer\t: 0x%02x\n", >> MIDR_IMPLEMENTOR(midr)); >> - seq_printf(m, "CPU architecture: 8\n"); >> + seq_printf(m, "CPU architecture: %d\n", MIDR_ARCHITECTURE(midr)); > Huh? Won't this always return 0xf? Hi Will, I'm not sure. My platform return 0xf, but /proc/cpuinfo show 8. Why we assign a fixed value to cpu architecture? Regards Liguang Zhang > > Will