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=-8.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 7A79FC433DF for ; Mon, 10 Aug 2020 10:21:43 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4302620729 for ; Mon, 10 Aug 2020 10:21:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="p053652D" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4302620729 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ynOdpo2FhfwbhtCGMSw4WhNmYYhZMpf1XciRuqx1QCE=; b=p053652DaTpT0BY5he3SdQA3F Ux5RNpapdpXzZX9qblYYNca9ucOQJXWRydDp+29LEXdq7mPmXbC/P3u4yi2IcT/2wQEH/BR8WK6j5 UvGzI6cCmntnOwK3gfkrIoTvV1YElAyXafBQJxLSXRFCA9Pm+V6N2HbiAjwPltUzIjasCoeZzg/qQ EH9cFRnk8OjSBO2ZhlCFaS6cH78ShTpvuSvMyW77D8fZXFd1qk655DBLZufaft8/mPdJnvat7Ffka qczn+42DxraqG1SQQFsNMdSaY44OTpUAmpHHaL9dwSXx5BKEQpJtglEe/r1nyZ6VlyK5fyWdjHjeG zwDmPb59Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k54uR-0007gx-CF; Mon, 10 Aug 2020 10:20:03 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1k54uP-0007gD-4X for linux-arm-kernel@lists.infradead.org; Mon, 10 Aug 2020 10:20:02 +0000 Received: from gaia (unknown [95.146.230.158]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 65823206C3; Mon, 10 Aug 2020 10:19:57 +0000 (UTC) Date: Mon, 10 Aug 2020 11:19:55 +0100 From: Catalin Marinas To: Sudeep Holla Subject: Re: [PATCH -next] arm64: Export __cpu_logical_map Message-ID: <20200810101954.GA9480@gaia> References: <20200724030433.22287-1-wangkefeng.wang@huawei.com> <82f750c4-d423-1ed8-a158-e75153745e07@huawei.com> <20200724131059.GB6521@bogus> <00cf6e67-16ed-872d-2c16-0ceea6b6f514@nvidia.com> <20200727160515.GA8003@bogus> <20200810074956.GB28091@bogus> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200810074956.GB28091@bogus> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200810_062001_338270_96741D0E X-CRM114-Status: GOOD ( 35.24 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kefeng Wang , Viresh Kumar , "linux-kernel@vger.kernel.org List" , Mikko Perttunen , Hulk Robot , Bibek Basu , Thierry Reding , linux-tegra , Sumit Gupta , Jon Hunter , Will Deacon , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Aug 10, 2020 at 08:49:56AM +0100, Sudeep Holla wrote: > On Sat, Aug 01, 2020 at 05:46:43PM +0530, Sumit Gupta wrote: > > > > > > > ERROR: modpost: "__cpu_logical_map" [drivers/cpufreq/tegra194-cpufreq.ko] undefined! > > > > > > > > > > > > > > ARM64 tegra194-cpufreq driver use cpu_logical_map, export > > > > > > > __cpu_logical_map to fix build issue. > > > > > > > > > > > > > > > > > I wonder why like other instances in the drivers, the mpidr is not get > > > > > directly from the cpu. The cpufreq_driver->init call happens when the cpu > > > > > is being brought online and is executed on the required cpu IIUC. > > > > > > > > Yes, this occurs during hotplug case. > > > > But in the case of system boot, 'cpufreq_driver->init' is called later > > > > during cpufreq platform driver's probe. The value of CPU in 'policy->cpu' > > > > can be different from the current CPU. That's why read_cpuid_mpidr() can't > > > > be used. > > > > > > Fair enough, why not do cross call like in set_target ? Since it is one-off > > > in init, I don't see any issue when you are doing it runtime for set_target. > > > > > > > > read_cpuid_mpidr() is inline and avoids having to export the logical_cpu_map. > > > > > Though we may not add physical hotplug anytime soon, less dependency > > > > > on this cpu_logical_map is better given that we can resolve this without > > > > > the need to access the map. > > > > > > To be honest, we have tried to remove all the dependency on cluster id > > > in generic code as it is not well defined. This one is tegra specific > > > driver so should be fine. But I am still bit nervous to export > > > cpu_logical_map as we have no clue what that would mean for physical > > > hotplug. > > > > As suggested, I have done below change to get the cluster number using > > read_cpuid_mpidr(). Please review and suggest if this looks ok? > > I will send formal patch if the change is fine. > > > > diff --git a/drivers/cpufreq/tegra194-cpufreq.c > > b/drivers/cpufreq/tegra194-cpufreq.c > > index bae527e..06f5ccf 100644 > > --- a/drivers/cpufreq/tegra194-cpufreq.c > > +++ b/drivers/cpufreq/tegra194-cpufreq.c > > @@ -56,9 +56,11 @@ struct read_counters_work { > > > > static struct workqueue_struct *read_counters_wq; > > > > -static enum cluster get_cpu_cluster(u8 cpu) > > +static void get_cpu_cluster(void *cluster) > > { > > - return MPIDR_AFFINITY_LEVEL(cpu_logical_map(cpu), 1); > > + u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK; > > + > > + *((uint32_t *) cluster) = MPIDR_AFFINITY_LEVEL(mpidr, 1); > > } > > > > /* > > @@ -186,8 +188,10 @@ static unsigned int tegra194_get_speed(u32 cpu) > > static int tegra194_cpufreq_init(struct cpufreq_policy *policy) > > { > > struct tegra194_cpufreq_data *data = cpufreq_get_driver_data(); > > - int cl = get_cpu_cluster(policy->cpu); > > u32 cpu; > > + u32 cl; > > + > > + smp_call_function_single(policy->cpu, get_cpu_cluster, &cl, true); > > Thanks for this, looks good to me. You can add: > > Reviewed-by: Sudeep Holla I already merged Kefeng's __cpu_logical_map fix (commit eaecca9e7710) but if the above goes in, I can drop the EXPORT_SYMBOL part (and keep the rest as it's a good refactoring). -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel