From patchwork Sat Jun 26 16:23:25 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: TungChen Shih X-Patchwork-Id: 467911 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY, URIBL_BLOCKED, USER_AGENT_GIT 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 BD78EC49EA6 for ; Sat, 26 Jun 2021 16:23:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5ECC661C42 for ; Sat, 26 Jun 2021 16:23:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229916AbhFZQ0P (ORCPT ); Sat, 26 Jun 2021 12:26:15 -0400 Received: from mailgw01.mediatek.com ([60.244.123.138]:43586 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S229890AbhFZQ0P (ORCPT ); Sat, 26 Jun 2021 12:26:15 -0400 X-UUID: 9c6cadf2445d4918b45d29e5eb155797-20210627 X-UUID: 9c6cadf2445d4918b45d29e5eb155797-20210627 Received: from mtkexhb02.mediatek.inc [(172.21.101.103)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 2102777713; Sun, 27 Jun 2021 00:23:48 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs01n1.mediatek.inc (172.21.101.68) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sun, 27 Jun 2021 00:23:47 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Sun, 27 Jun 2021 00:23:47 +0800 From: TungChen Shih To: , , CC: , , , , , TungChen Shih Subject: [PATCH v2 1/1] cpufreq: fix the target freq not in the range of policy->min & max Date: Sun, 27 Jun 2021 00:23:25 +0800 Message-ID: <20210626162324.8236-1-tung-chen.shih@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org The function cpufreq_driver_resolve_freq() should return the lowest supported freq greater than or equal to the given target_freq, subject to policy (min/max) and driver limitations. However, the index returned by cpufreq_frequency_table_target() won't subject to policy min/max in some cases. In cpufreq_frequency_table_target(), this function will try to find an index for @target_freq in freq_table, and the frequency of selected index should be in the range [policy->min, policy->max], which means: policy->min <= policy->freq_table[idx].frequency <= policy->max Though "clamp_val(target_freq, policy->min, policy->max);" would have been called to check this condition, when policy->max or min is not exactly one of the frequency in the frequency table, policy->freq_table[idx].frequency may still go out of the range For example, if our sorted freq_table is [3000, 2000, 1000], and suppose we have: @target_freq = 2500 @policy->min = 2000 @policy->max = 2200 @relation = CPUFREQ_RELATION_L 1. After clamp_val(target_freq, policy->min, policy->max); @target_freq becomes 2200 2. Since we use CPUFREQ_REALTION_L, final selected freq will be 3000 which beyonds policy->max Signed-off-by: TungChen Shih --- drivers/cpufreq/cpufreq.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 802abc925b2a..8e3a17781618 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -544,8 +544,23 @@ unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, if (cpufreq_driver->target_index) { unsigned int idx; + /* to find the frequency >= target_freq */ idx = cpufreq_frequency_table_target(policy, target_freq, CPUFREQ_RELATION_L); + + /* frequency should subject to policy (min/max) */ + if (policy->freq_table[idx].frequency > policy->max) { + if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING) + idx--; + else + idx++; + } else if (policy->freq_table[idx].frequency < policy->min) { + if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING) + idx++; + else + idx--; + } + policy->cached_resolved_idx = idx; return policy->freq_table[idx].frequency; }