From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id AEA3C4778B; Thu, 29 Feb 2024 09:59:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709200767; cv=none; b=t7eaQsQwOJdMFUvC1ij+FyLDKvLbvvEGmkAmt6Pdz0XA3Y1Sc/DPjvG1HHwZfN0tIM4rV5OJTmtd0uTFU8s5zgbfyh3AkPJIIqn44TLIAiL2Lptn8yaDflS7EfeAhH/31Ih2oSIRrvcKmZyty83o3nn4lgD8lZButus236wVMCI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709200767; c=relaxed/simple; bh=LomPs8yZabTBRuijVP1x/mNDGcz7vRh2TwpwQn7qTaE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=SalbO/JLdOAzHU+JIKN36oxhYOyoNfHYf7ZOesAtM8eytNoJ+WgUFIu0E/MYqrpXGxun6u+2A7uyMIBTjjfENTvivltZGGvkMa/8fNsiH501KS8q/dixT0XCz4b9UE7PIUWysvCjHwFCcAWOyTcc9ZMInamBFWW1hB0E7mPkg4I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 578EA1FB; Thu, 29 Feb 2024 02:00:02 -0800 (PST) Received: from [10.57.12.184] (unknown [10.57.12.184]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3B1633F762; Thu, 29 Feb 2024 01:59:21 -0800 (PST) Message-ID: <64c6a1bc-92f2-4f44-ab10-cbd2473746f3@arm.com> Date: Thu, 29 Feb 2024 09:59:38 +0000 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH V3 2/2] cpufreq: scmi: Register for limit change notifications Content-Language: en-US To: Sibi Sankar Cc: linux-arm-kernel@lists.infradead.org, pierre.gondois@arm.com, dietmar.eggemann@arm.com, morten.rasmussen@arm.com, viresh.kumar@linaro.org, rafael@kernel.org, cristian.marussi@arm.com, sudeep.holla@arm.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, quic_mdtipton@quicinc.com, linux-arm-msm@vger.kernel.org References: <20240227181632.659133-1-quic_sibis@quicinc.com> <20240227181632.659133-3-quic_sibis@quicinc.com> <2608b2d8-f3b0-b4f5-f8e4-1f2242043ded@quicinc.com> From: Lukasz Luba In-Reply-To: <2608b2d8-f3b0-b4f5-f8e4-1f2242043ded@quicinc.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 2/28/24 17:00, Sibi Sankar wrote: > > > On 2/28/24 18:54, Lukasz Luba wrote: >> >> >> On 2/27/24 18:16, Sibi Sankar wrote: >>> Register for limit change notifications if supported and use the >>> throttled >>> frequency from the notification to apply HW pressure. > > Lukasz, > > Thanks for taking time to review the series! > >>> >>> Signed-off-by: Sibi Sankar >>> --- >>> >>> v3: >>> * Sanitize range_max received from the notifier. [Pierre] >>> * Update commit message. >>> >>>   drivers/cpufreq/scmi-cpufreq.c | 29 ++++++++++++++++++++++++++++- >>>   1 file changed, 28 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/cpufreq/scmi-cpufreq.c >>> b/drivers/cpufreq/scmi-cpufreq.c >>> index 76a0ddbd9d24..78b87b72962d 100644 >>> --- a/drivers/cpufreq/scmi-cpufreq.c >>> +++ b/drivers/cpufreq/scmi-cpufreq.c >>> @@ -25,9 +25,13 @@ struct scmi_data { >>>       int domain_id; >>>       int nr_opp; >>>       struct device *cpu_dev; >>> +    struct cpufreq_policy *policy; >>>       cpumask_var_t opp_shared_cpus; >>> +    struct notifier_block limit_notify_nb; >>>   }; >>> +const struct scmi_handle *handle; I've missed this bit here. >>> +static struct scmi_device *scmi_dev; >>>   static struct scmi_protocol_handle *ph; >>>   static const struct scmi_perf_proto_ops *perf_ops; >>>   static struct cpufreq_driver scmi_cpufreq_driver; >>> @@ -151,6 +155,20 @@ static struct freq_attr *scmi_cpufreq_hw_attr[] = { >>>       NULL, >>>   }; >>> +static int scmi_limit_notify_cb(struct notifier_block *nb, unsigned >>> long event, void *data) >>> +{ >>> +    struct scmi_data *priv = container_of(nb, struct scmi_data, >>> limit_notify_nb); >>> +    struct scmi_perf_limits_report *limit_notify = data; >>> +    struct cpufreq_policy *policy = priv->policy; >>> + >>> +    policy->max = clamp(limit_notify->range_max_freq/HZ_PER_KHZ, >>> policy->cpuinfo.min_freq, >>> +                policy->cpuinfo.max_freq); >> >> Please take the division operation out of this clamp() call, somewhere >> above. Currently it 'blurs' these stuff, while it's important convertion >> to khz. You can call it e.g.: >> >> limit_freq_khz = limit_notify->range_max_freq / HZ_PER_KHZ; >> >> then use in clamp(limit_freq_khz, ...) > > ack > >> >>> + >>> +    cpufreq_update_pressure(policy); >>> + >>> +    return NOTIFY_OK; >>> +} >>> + >>>   static int scmi_cpufreq_init(struct cpufreq_policy *policy) >>>   { >>>       int ret, nr_opp, domain; >>> @@ -269,6 +287,15 @@ static int scmi_cpufreq_init(struct >>> cpufreq_policy *policy) >>>           } >>>       } >>> +    priv->limit_notify_nb.notifier_call = scmi_limit_notify_cb; >>> +    ret = handle->notify_ops->devm_event_notifier_register(scmi_dev, >>> SCMI_PROTOCOL_PERF, >>> +                            SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED, >>> +                            &domain, >>> +                            &priv->limit_notify_nb); >>> +    if (ret) >>> +        dev_warn(cpu_dev, >>> +             "failed to register for limits change notifier for >>> domain %d\n", domain); >>> + >>>       priv->policy = policy; >>>       return 0; >>> @@ -342,8 +369,8 @@ static int scmi_cpufreq_probe(struct scmi_device >>> *sdev) >>>   { >>>       int ret; >>>       struct device *dev = &sdev->dev; >>> -    const struct scmi_handle *handle; >> >> It should be a compilation error... >> >>> +    scmi_dev = sdev; >>>       handle = sdev->handle; >> >> due to usage here, wasn't it? > > Not really, isn't it getting the first initialization here? > Are there any compiler options that I need to turn on to > catch these? Yes, you're right, my apologies for confusion. I couldn't apply the series due issues in two patch sets in your dependency list. Now when I have been manually applying the changes I spotted it.