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 B1B7B5C911; Tue, 26 Mar 2024 10:09:10 +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=1711447752; cv=none; b=ghHrl6udP13ri9aRvEixaMbj3m6TYEoxM6ZP4+6TCLJFTvpPKNMJOEDLTNCgEc8FLGGjX4qUp64tEMCa6vbMAYiAUpTJ7J3cCQTG8x9+S17WY9jRJv5oZwpviJjJRkS4op8A8Nj3Xi2aR8esTpadIMqJCntarGOqtRDw3chObEA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711447752; c=relaxed/simple; bh=0qqyjsoUJJgOhHL/bgPaKR1WiY++FeUVJ10GLBY70VU=; h=Message-ID:Date:MIME-Version:From:Subject:To:Cc:References: In-Reply-To:Content-Type; b=dx2B60yOjviZtGgALVud1lI348Jn14SrEIZ7XMauujzAK5wHN4JnpMT9AFLo7qiPjMUZ36uu+KPrvHQpJmd1KTkJelTpdH+e3uCLVMSlgwTCJHY/OkxfoaTv2btYqj/LnuOy3bZFEo4wQqY+90Rs+UzEmFf54NNOAfKJPwmupRw= 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 6A093339; Tue, 26 Mar 2024 03:09:43 -0700 (PDT) Received: from [10.57.15.246] (unknown [10.57.15.246]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 807503F64C; Tue, 26 Mar 2024 03:09:07 -0700 (PDT) Message-ID: Date: Tue, 26 Mar 2024 11:09:05 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Dietmar Eggemann Subject: Re: [RESEND][PATCH v2 3/4] PM: EM: Add em_dev_update_chip_binning() To: Lukasz Luba , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, sboyd@kernel.org, nm@ti.com, linux-samsung-soc@vger.kernel.org, daniel.lezcano@linaro.org, rafael@kernel.org, viresh.kumar@linaro.org, krzysztof.kozlowski@linaro.org, alim.akhtar@samsung.com, m.szyprowski@samsung.com, mhiramat@kernel.org References: <20240322110850.77086-1-lukasz.luba@arm.com> <20240322110850.77086-4-lukasz.luba@arm.com> Content-Language: en-US In-Reply-To: <20240322110850.77086-4-lukasz.luba@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 22/03/2024 12:08, Lukasz Luba wrote: > diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c > index 6960dd7393b2d..f7f7ae34ec552 100644 > --- a/kernel/power/energy_model.c > +++ b/kernel/power/energy_model.c > @@ -808,3 +808,54 @@ static void em_update_workfn(struct work_struct *work) > { > em_check_capacity_update(); > } > + > +/** > + * em_dev_update_chip_binning() - Update Energy Model with new values after s/with new values// ... IMHO this should be obvious ? > + * the new voltage information is present in the OPPs. > + * @dev : Device for which the Energy Model has to be updated. > + * > + * This function allows to update easily the EM with new values available in > + * the OPP framework and DT. It can be used after the chip has been properly > + * verified by device drivers and the voltages adjusted for the 'chip binning'. > + * It uses the "dynamic-power-coefficient" DT property to calculate the power > + * values for EM. For power calculation it uses the new adjusted voltage > + * values known for OPPs, which might be changed after boot. The last two sentences describe what dev_pm_opp_calc_power() is doing. Maybe this can be made clearer here? > + */ > +int em_dev_update_chip_binning(struct device *dev) This is the old dev_pm_opp_of_update_em() right? > +{ > + struct em_perf_table __rcu *em_table; > + struct em_perf_domain *pd; > + int i, ret; > + > + if (IS_ERR_OR_NULL(dev)) > + return -EINVAL; When do you use if '(IS_ERR_OR_NULL(dev))' and when 'if(!dev)' for EM interface functions? > + pd = em_pd_get(dev); > + if (!pd) { > + dev_warn(dev, "Couldn't find Energy Model\n"); > + return -EINVAL; > + } > + > + em_table = em_table_dup(pd); > + if (!em_table) { > + dev_warn(dev, "EM: allocation failed\n"); > + return -ENOMEM; > + } > + > + /* Update power values which might change due to new voltage in OPPs */ > + for (i = 0; i < pd->nr_perf_states; i++) { > + unsigned long freq = em_table->state[i].frequency; > + unsigned long power; > + > + ret = dev_pm_opp_calc_power(dev, &power, &freq); > + if (ret) { > + em_table_free(em_table); > + return ret; > + } > + > + em_table->state[i].power = power; > + } > + > + return em_recalc_and_update(dev, pd, em_table); > +} > +EXPORT_SYMBOL_GPL(em_dev_update_chip_binning); In the previous version of 'chip-binning' you were using the new EM interface em_dev_compute_costs() (1) which is now replaced by em_recalc_and_update() -> em_compute_costs(). https://lkml.kernel.org/r/20231220110339.1065505-2-lukasz.luba@arm.com Which leaves (1) still unused. That was why my concern back then that we shouldn't introduce EM interfaces without a user: https://lkml.kernel.org/r/8fc499cf-fca1-4465-bff7-a93dfd36f3c8@arm.com What happens now with em_dev_compute_costs()?