From patchwork Tue Dec 20 10:12:25 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pierre Gondois X-Patchwork-Id: 13077709 X-Patchwork-Delegate: viresh.linux@gmail.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7857BC4332F for ; Tue, 20 Dec 2022 10:13:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233217AbiLTKND (ORCPT ); Tue, 20 Dec 2022 05:13:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39066 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233272AbiLTKNC (ORCPT ); Tue, 20 Dec 2022 05:13:02 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 4475B2653; Tue, 20 Dec 2022 02:13:01 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B99772F4; Tue, 20 Dec 2022 02:13:41 -0800 (PST) Received: from pierre123.nice.arm.com (pierre123.nice.arm.com [10.34.100.128]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id A2F863F71A; Tue, 20 Dec 2022 02:12:59 -0800 (PST) From: Pierre Gondois To: linux-kernel@vger.kernel.org Cc: james.clark@arm.com, Ionela.Voinescu@arm.com, Pierre Gondois , "Rafael J. Wysocki" , Viresh Kumar , linux-pm@vger.kernel.org Subject: [PATCH] cpufreq: CPPC: Add u64 casts to avoid overflowing Date: Tue, 20 Dec 2022 11:12:25 +0100 Message-Id: <20221220101225.3190672-1-pierre.gondois@arm.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org The fields of the _CPC object are unsigned 32-bits values. To avoid overflows while using _CPC's values, add 'u64' casts. Signed-off-by: Pierre Gondois --- drivers/cpufreq/cppc_cpufreq.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c index 432dfb4e8027..022e3555407c 100644 --- a/drivers/cpufreq/cppc_cpufreq.c +++ b/drivers/cpufreq/cppc_cpufreq.c @@ -487,7 +487,8 @@ static unsigned int get_perf_level_count(struct cpufreq_policy *policy) cpu_data = policy->driver_data; perf_caps = &cpu_data->perf_caps; max_cap = arch_scale_cpu_capacity(cpu); - min_cap = div_u64(max_cap * perf_caps->lowest_perf, perf_caps->highest_perf); + min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf, + perf_caps->highest_perf); if ((min_cap == 0) || (max_cap < min_cap)) return 0; return 1 + max_cap / CPPC_EM_CAP_STEP - min_cap / CPPC_EM_CAP_STEP; @@ -519,10 +520,10 @@ static int cppc_get_cpu_power(struct device *cpu_dev, cpu_data = policy->driver_data; perf_caps = &cpu_data->perf_caps; max_cap = arch_scale_cpu_capacity(cpu_dev->id); - min_cap = div_u64(max_cap * perf_caps->lowest_perf, - perf_caps->highest_perf); - - perf_step = CPPC_EM_CAP_STEP * perf_caps->highest_perf / max_cap; + min_cap = div_u64((u64)max_cap * perf_caps->lowest_perf, + perf_caps->highest_perf); + perf_step = div_u64((u64)CPPC_EM_CAP_STEP * perf_caps->highest_perf, + max_cap); min_step = min_cap / CPPC_EM_CAP_STEP; max_step = max_cap / CPPC_EM_CAP_STEP;