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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 3D83CC433E0 for ; Mon, 1 Feb 2021 11:24:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2CD164DA5 for ; Mon, 1 Feb 2021 11:24:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233361AbhBALY0 (ORCPT ); Mon, 1 Feb 2021 06:24:26 -0500 Received: from foss.arm.com ([217.140.110.172]:56696 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233560AbhBALYY (ORCPT ); Mon, 1 Feb 2021 06:24:24 -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 929031042; Mon, 1 Feb 2021 03:23:38 -0800 (PST) Received: from [10.57.8.191] (unknown [10.57.8.191]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7568A3F718; Mon, 1 Feb 2021 03:23:36 -0800 (PST) Subject: Re: [RFC][PATCH 0/3] New thermal interface allowing IPA to get max power To: daniel.lezcano@linaro.org, cw00.choi@samsung.com Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, vireshk@kernel.org, rafael@kernel.org, Dietmar.Eggemann@arm.com, amitk@kernel.org, rui.zhang@intel.com, myungjoo.ham@samsung.com, kyungmin.park@samsung.com References: <20210126104001.20361-1-lukasz.luba@arm.com> From: Lukasz Luba Message-ID: <5751adfa-6e25-3f3c-4a60-9b3c739fec1f@arm.com> Date: Mon, 1 Feb 2021 11:23:34 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20210126104001.20361-1-lukasz.luba@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Daniel, Chanwoo Gentle ping. Have you have a chance to check these patches? On 1/26/21 10:39 AM, Lukasz Luba wrote: > Hi all, > > This patch set tries to add the missing feature in the Intelligent Power > Allocation (IPA) governor which is: frequency limit set by user space. > User can set max allowed frequency for a given device which has impact on > max allowed power. In current design there is no mechanism to figure this > out. IPA must know the maximum allowed power for every device. It is then > used for proper power split and divvy-up. When the user limit for max > frequency is not know, IPA assumes it is the highest possible frequency. > It causes wrong power split across the devices. > > This new mechanism provides the max allowed frequency to the thermal > framework and then max allowed power to the IPA. > The implementation is done in this way because currently there is no way > to retrieve the limits from the PM QoS, without uncapping the local > thermal limit and reading the next value. It would be a heavy way of > doing these things, since it should be done every polling time (e.g. 50ms). > Also, the value stored in PM QoS can be different than the real OPP 'rate' > so still would need conversion into proper OPP for comparison with EM. > Furthermore, uncapping the device in thermal just to check the user freq > limit is not the safest way. > Thus, this simple implementation moves the calculation of the proper > frequency to the sysfs write code, since it's called less often. The value > is then used as-is in the thermal framework without any hassle. > > As it's a RFC, it still misses the cpufreq sysfs implementation, but would > be addressed if all agree. > > Regards, > Lukasz Luba > > Lukasz Luba (3): > PM /devfreq: add user frequency limits into devfreq struct > thermal: devfreq_cooling: add new callback to get user limit for min > state > thermal: power_allocator: get proper max power limited by user > > drivers/devfreq/devfreq.c | 41 ++++++++++++++++++++++++--- > drivers/thermal/devfreq_cooling.c | 33 +++++++++++++++++++++ > drivers/thermal/gov_power_allocator.c | 17 +++++++++-- > include/linux/devfreq.h | 4 +++ > include/linux/thermal.h | 1 + > 5 files changed, 90 insertions(+), 6 deletions(-) >