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=-5.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,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 20B29C432C0 for ; Wed, 27 Nov 2019 08:36:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DD38320684 for ; Wed, 27 Nov 2019 08:36:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="yHpRnVxI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726135AbfK0IgY (ORCPT ); Wed, 27 Nov 2019 03:36:24 -0500 Received: from mail-pf1-f196.google.com ([209.85.210.196]:34400 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726133AbfK0IgY (ORCPT ); Wed, 27 Nov 2019 03:36:24 -0500 Received: by mail-pf1-f196.google.com with SMTP id n13so10637636pff.1 for ; Wed, 27 Nov 2019 00:36:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=kEWlTxImZpdkwXhGS8325FceSNRBs8VLhunG13s9KAM=; b=yHpRnVxIjSPnmIdbMbeu/tYzFBYDtKTTB287cO1KR1bARwSmREn/eQP74Bl7Af9/y8 a82ewmL2RBQDxl2XmBxTNBAL+KaxJmKAwlKSRl+2cOkk7//wvP6vjlBiIup/h7v2jo8V hD3ZtLbo9ZCwivNiTAZq2pUpGLBvhYf0Fvj3PTlMiN0akT2u3kqKvVPIDeYgrbSC2Cb9 ERUMql/9D07dmErr5NA8VCMA753S+WHPa1jovOmvlhsanFxOuurKFWr5XnitU2n4yk0s 6g95m1QCflgnf2y6N/vMnCzgc3LucbF8wwRMWAlX49Y/dCTaJfA0G0K6Ehqx6Ay7WAr2 baJg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=kEWlTxImZpdkwXhGS8325FceSNRBs8VLhunG13s9KAM=; b=kWfP72U7x8K3NbeHKYCKhnjZddKveL8jjhMFM9PNWryF1qluIHEnFt+DPWlS6GE2d4 mCvZb3bEkusebq6yRlNSgegQPFVuUc1G1OZoUzmVe4KrQuxolvqf/uxjsSCj8jmIFblW GlGQY/lxuVSjRlJazztjZ21K/xOkFJ1Cq4ydhh4yh33byZzV+Cf9Ogrwp29ZVFS3bKFc Iq+jFICNYMAk52H9mSqdmhUmBoj4FYv1DveRkCNoAbq4SdYGSCLIa785k6VMrw6n9GnQ S78ncdT7y9UEZd6oCqALbcw3R8Yvc2jXvI2zaBfiStDbuLJ8k39nW07bWj1Wqd41ALLf 9mZA== X-Gm-Message-State: APjAAAVYgKRE/w81bBnDpOQco+dppMxo7j6mOE/wXPiln1L1yVWy9vqk gAbEcMHO0S5YmHg/GPUhCzBcLQ== X-Google-Smtp-Source: APXvYqz6ciA/bE2sIdxV8IrR+vllOp4Mb3eFxMKadK3NK074FLo5rfjIe4sBJET8JrQj229M/EAXpQ== X-Received: by 2002:a63:1b1f:: with SMTP id b31mr3451053pgb.177.1574843782900; Wed, 27 Nov 2019 00:36:22 -0800 (PST) Received: from localhost ([122.171.112.123]) by smtp.gmail.com with ESMTPSA id k24sm15884442pfk.63.2019.11.27.00.36.21 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 27 Nov 2019 00:36:21 -0800 (PST) Date: Wed, 27 Nov 2019 14:06:19 +0530 From: Viresh Kumar To: "Andrew-sh.Cheng" Cc: MyungJoo Ham , Kyungmin Park , Chanwoo Choi , Rob Herring , Mark Rutland , Matthias Brugger , "Rafael J. Wysocki" , Nishanth Menon , Stephen Boyd , linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, srv_heupstream@mediatek.com, fan.chen@mediatek.com Subject: Re: [v5, PATCH 4/5] cpufreq: mediatek: add opp notification for SVS support Message-ID: <20191127083619.etocnhpyyut3hzwq@vireshk-i7> References: <1574769046-28449-1-git-send-email-andrew-sh.cheng@mediatek.com> <1574769046-28449-5-git-send-email-andrew-sh.cheng@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1574769046-28449-5-git-send-email-andrew-sh.cheng@mediatek.com> User-Agent: NeoMutt/20180716-391-311a52 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On 26-11-19, 19:50, Andrew-sh.Cheng wrote: > diff --git a/drivers/cpufreq/mediatek-cpufreq.c b/drivers/cpufreq/mediatek-cpufreq.c > index 4b0cc50dd93b..7c37ab31230a 100644 > --- a/drivers/cpufreq/mediatek-cpufreq.c > +++ b/drivers/cpufreq/mediatek-cpufreq.c > @@ -42,6 +42,10 @@ struct mtk_cpu_dvfs_info { > struct list_head list_head; > int intermediate_voltage; > bool need_voltage_tracking; > + struct mutex lock; /* avoid notify and policy race condition */ Will a read-write lock be better suited here for performance reasons ? > + struct notifier_block opp_nb; > + int opp_cpu; > + unsigned long opp_freq; > }; > > static LIST_HEAD(dvfs_info_list); > @@ -231,6 +235,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, > vproc = dev_pm_opp_get_voltage(opp); > dev_pm_opp_put(opp); > > + mutex_lock(&info->lock); > /* > * If the new voltage or the intermediate voltage is higher than the > * current voltage, scale up voltage first. > @@ -242,6 +247,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, > pr_err("cpu%d: failed to scale up voltage!\n", > policy->cpu); > mtk_cpufreq_set_voltage(info, old_vproc); > + mutex_unlock(&info->lock); > return ret; > } > } > @@ -253,6 +259,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, > policy->cpu); > mtk_cpufreq_set_voltage(info, old_vproc); > WARN_ON(1); > + mutex_unlock(&info->lock); > return ret; > } > > @@ -263,6 +270,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, > policy->cpu); > clk_set_parent(cpu_clk, armpll); > mtk_cpufreq_set_voltage(info, old_vproc); > + mutex_unlock(&info->lock); > return ret; > } > > @@ -273,6 +281,7 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, > policy->cpu); > mtk_cpufreq_set_voltage(info, inter_vproc); > WARN_ON(1); > + mutex_unlock(&info->lock); > return ret; > } > > @@ -288,15 +297,75 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy, > clk_set_parent(cpu_clk, info->inter_clk); > clk_set_rate(armpll, old_freq_hz); > clk_set_parent(cpu_clk, armpll); > + mutex_unlock(&info->lock); > return ret; > } > } > > + info->opp_freq = freq_hz; > + mutex_unlock(&info->lock); > + > return 0; > } > > #define DYNAMIC_POWER "dynamic-power-coefficient" > > +static int mtk_cpufreq_opp_notifier(struct notifier_block *nb, > + unsigned long event, void *data) > +{ > + struct dev_pm_opp *opp = data; > + struct dev_pm_opp *opp_item; > + struct mtk_cpu_dvfs_info *info = > + container_of(nb, struct mtk_cpu_dvfs_info, opp_nb); Do the assignment after all definitions, instead of awkwardly breaking the line here. > + unsigned long freq, volt; > + struct cpufreq_policy *policy; > + int ret = 0; > + > + if (event == OPP_EVENT_ADJUST_VOLTAGE) { > + freq = dev_pm_opp_get_freq(opp); > + > + mutex_lock(&info->lock); > + if (info->opp_freq == freq) { > + volt = dev_pm_opp_get_voltage(opp); > + ret = mtk_cpufreq_set_voltage(info, volt); > + if (ret) > + dev_err(info->cpu_dev, "failed to scale voltage: %d\n", > + ret); > + } > + mutex_unlock(&info->lock); > + } else if (event == OPP_EVENT_DISABLE) { > + freq = info->opp_freq; > + opp_item = dev_pm_opp_find_freq_ceil(info->cpu_dev, &freq); name it new_opp instead of opp_item. > + if (!IS_ERR(opp_item)) > + dev_pm_opp_put(opp_item); > + else > + freq = 0; > + What is the purpose of the above code ? > + /* case of current opp is disabled */ > + if (freq == 0 || freq != info->opp_freq) { > + // find an enable opp item Use proper commenting style please. > + freq = 1; > + opp_item = dev_pm_opp_find_freq_ceil(info->cpu_dev, > + &freq); > + if (!IS_ERR(opp_item)) { > + dev_pm_opp_put(opp_item); > + policy = cpufreq_cpu_get(info->opp_cpu); > + if (policy) { > + cpufreq_driver_target(policy, > + freq / 1000, > + CPUFREQ_RELATION_L); Why don't you simply call this instead of all the code in the else block ? > + cpufreq_cpu_put(policy); > + } > + } else { > + pr_err("%s: all opp items are disabled\n", > + __func__); > + } > + } > + } > + > + return notifier_from_errno(ret); > +} > + > static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu) > { > struct device *cpu_dev; > @@ -383,11 +452,21 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu) > info->intermediate_voltage = dev_pm_opp_get_voltage(opp); > dev_pm_opp_put(opp); > > + info->opp_cpu = cpu; > + info->opp_nb.notifier_call = mtk_cpufreq_opp_notifier; > + ret = dev_pm_opp_register_notifier(cpu_dev, &info->opp_nb); > + if (ret) { > + pr_warn("cannot register opp notification\n"); > + goto out_free_opp_table; > + } > + > + mutex_init(&info->lock); > info->cpu_dev = cpu_dev; > info->proc_reg = proc_reg; > info->sram_reg = IS_ERR(sram_reg) ? NULL : sram_reg; > info->cpu_clk = cpu_clk; > info->inter_clk = inter_clk; > + info->opp_freq = clk_get_rate(cpu_clk); > > /* > * If SRAM regulator is present, software "voltage tracking" is needed > -- > 2.12.5 -- viresh