From patchwork Fri Jan 8 15:14:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ionela Voinescu X-Patchwork-Id: 12006845 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 X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 145D1C433DB for ; Fri, 8 Jan 2021 15:20:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2B49239EB for ; Fri, 8 Jan 2021 15:20:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726650AbhAHPUd (ORCPT ); Fri, 8 Jan 2021 10:20:33 -0500 Received: from foss.arm.com ([217.140.110.172]:52996 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726600AbhAHPUd (ORCPT ); Fri, 8 Jan 2021 10:20:33 -0500 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 41474113E; Fri, 8 Jan 2021 07:19:48 -0800 (PST) Received: from e108754-lin.cambridge.arm.com (unknown [10.1.198.32]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 0B29C3F70D; Fri, 8 Jan 2021 07:19:46 -0800 (PST) From: Ionela Voinescu To: rjw@rjwysocki.net, viresh.kumar@linaro.org, manivannan.sadhasivam@linaro.org, agross@kernel.org, bjorn.andersson@linaro.org Cc: amitk@kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Ionela Voinescu Subject: [PATCH] cpufreq: Revert "cpufreq: qcom-hw: Use devm_platform_ioremap_resource() to simplify code" Date: Fri, 8 Jan 2021 15:14:06 +0000 Message-Id: <20210108151406.23595-1-ionela.voinescu@arm.com> X-Mailer: git-send-email 2.29.2.dirty MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org This reverts commit f17b3e44320b4079e69135c63d1e416b0703a21e. This commit introduces a regression on platforms using the driver, by failing to initialise a policy, when one is created post hotplug. When all the CPUs of a policy are hoptplugged out, the call to .exit() and later to devm_iounmap() does not release the memory region that was requested during devm_platform_ioremap_resource(). Therefore, a subsequent call to .init() will result in the following error, which will prevent a new policy to be initialised: qcom-cpufreq-hw 17d43000.cpufreq: can't request region for resource [mem 0x17d43000-0x17d443ff] Signed-off-by: Ionela Voinescu --- Hi guys, I noticed the issue described in the commit message on DB845c platforms on 5.11-rc2. I tried to fix this, rather than revert it, but I did not find any better way to fix this, other than possibly calling devm_release_mem_region() directly in the cpufreq driver or reworking some of the resource management functions. But in comparison, reverting the patch still seemed the cleaner solution to me. Hope it helps, Ionela. drivers/cpufreq/qcom-cpufreq-hw.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) base-commit: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62 prerequisite-patch-id: a6b26dcf2cc7750362150ced269bc05a6cbd0a05 diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c index 9ed5341dc515..79e637616856 100644 --- a/drivers/cpufreq/qcom-cpufreq-hw.c +++ b/drivers/cpufreq/qcom-cpufreq-hw.c @@ -280,6 +280,7 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy) struct of_phandle_args args; struct device_node *cpu_np; struct device *cpu_dev; + struct resource *res; void __iomem *base; struct qcom_cpufreq_data *data; int ret, index; @@ -303,9 +304,13 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy) index = args.args[0]; - base = devm_platform_ioremap_resource(pdev, index); - if (IS_ERR(base)) - return PTR_ERR(base); + res = platform_get_resource(pdev, IORESOURCE_MEM, index); + if (!res) + return -ENODEV; + + base = devm_ioremap(dev, res->start, resource_size(res)); + if (!base) + return -ENOMEM; data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); if (!data) {