From patchwork Tue Oct 27 16:42:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Pearson X-Patchwork-Id: 295613 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=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 3C9F8C5517A for ; Tue, 27 Oct 2020 16:43:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 024F321707 for ; Tue, 27 Oct 2020 16:43:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1811852AbgJ0Qmw (ORCPT ); Tue, 27 Oct 2020 12:42:52 -0400 Received: from mail1.bemta24.messagelabs.com ([67.219.250.116]:24365 "EHLO mail1.bemta24.messagelabs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1811836AbgJ0Qmu (ORCPT ); Tue, 27 Oct 2020 12:42:50 -0400 Received: from [100.112.135.1] (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256 bits)) by server-5.bemta.az-b.us-west-2.aws.symcld.net id 06/B9-42875-70E489F5; Tue, 27 Oct 2020 16:42:47 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFuplleJIrShJLcpLzFFi42JJl3vFpsvuNyP eYMFWUYv91yUsuhYaWCy8f4rV4uu32+wWb45PZ7JYvq+f0eLyrjlsFp97jzBaNHU2AVkdk1ks Vu95wezA7TFp5gxmj52z7rJ7/Nq2hsVj8wotj3knAz3e77vK5vF5k1wAexRrZl5SfkUCa8aZs 5IFX5UqFt7KamB8ItvFyMUhJPCfUeLZ8cWMXYycQM4bRomXG4tAbDYBbYktW36xdTFycIgIyE h8WOsJEmYW2MskseNvCogtLBAl8f1JDwuIzSKgKvFt2142EJtXwEbi0KxnYCMlBOQlnvYuZwa xOYFqznQ9ZoFYpSJx/8ESqHpBiZMzn7BAzJeXaN46mxnClpA4+OIFM8QcBYlvd78xQdgJEste 3mGewCgwC0n7LCTts5C0L2BkXsVollSUmZ5RkpuYmaNraGCga2hopGtobKRroZdYpZukV1qsW 55aXKJrpJdYXqxXXJmbnJOil5dasokRGEspBS0cOxgPv/6gd4hRkoNJSZR3iceMeCG+pPyUyo zE4oz4otKc1OJDjDIcHEoSvNo+QDnBotT01Iq0zBxgXMOkJTh4lER4J4KkeYsLEnOLM9MhUqc YFaXEedeDJARAEhmleXBtsFRyiVFWSpiXkYGBQYinILUoN7MEVf4VozgHo5Iw73uQKTyZeSVw 018BLWYCWtxWMQVkcUkiQkqqgcn59Gm9FSua+vveO7mYvo+/91DQvyVvwZTpfzdl/X74vu/vr Orgx6mu6+pPy37e3RMQuXj73KVfHi3dXrA2ZbHR5mlJz84//3krcR/7jC1PD15u3K5boKJ5Me Dt0nPXplsozH9WMslVuZt9ckdOgO2NS+ImqQcebKqcnsE2w1xJbM5m17Cj8615Drkff6GUFVh 4efKqlVz9+huuMczfV/coQyPy+ppXU2bPU883U8na5tHQ9G3Ts2W/qx7l+keazb+b5lSZ7xv+ Iz1Xx1sgMGOn16Uz+otM3gt+XVlf8P7bPkapCdk5V3e/f8grV+sQHige5vFvsUSE5dqwhF0tK 1j177qv3PM04lVuKZPn5CUiSizFGYmGWsxFxYkA1pxFwqADAAA= X-Env-Sender: markpearson@lenovo.com X-Msg-Ref: server-3.tower-355.messagelabs.com!1603816965!7460!1 X-Originating-IP: [103.30.234.6] X-SYMC-ESS-Client-Auth: outbound-route-from=pass X-StarScan-Received: X-StarScan-Version: 9.60.3; banners=-,-,- X-VirusChecked: Checked Received: (qmail 16068 invoked from network); 27 Oct 2020 16:42:47 -0000 Received: from unknown (HELO lenovo.com) (103.30.234.6) by server-3.tower-355.messagelabs.com with ECDHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 27 Oct 2020 16:42:47 -0000 Received: from reswpmail04.lenovo.com (unknown [10.62.32.23]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by Forcepoint Email with ESMTPS id 7B7A14184040F8AEE639; Wed, 28 Oct 2020 00:42:42 +0800 (CST) Received: from localhost.localdomain.com (10.64.85.148) by reswpmail04.lenovo.com (10.62.32.23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2044.4; Tue, 27 Oct 2020 09:42:37 -0700 From: Mark Pearson To: CC: , , , , , , , , , , Hans de Goede Subject: [PATCH] Documentation: Add documentation for new platform_profile sysfs attribute Date: Tue, 27 Oct 2020 12:42:19 -0400 Message-ID: <20201027164219.868839-1-markpearson@lenovo.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: References: MIME-Version: 1.0 X-Originating-IP: [10.64.85.148] X-ClientProxiedBy: reswpmail04.lenovo.com (10.62.32.23) To reswpmail04.lenovo.com (10.62.32.23) Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Hans de Goede On modern systems the platform performance, temperature, fan and other hardware related characteristics are often dynamically configurable. The profile is often automatically adjusted to the load by somei automatic-mechanism (which may very well live outside the kernel). These auto platform-adjustment mechanisms often can be configured with one of several 'platform-profiles', with either a bias towards low-power consumption or towards performance (and higher power consumption and thermals). Introduce a new platform_profile sysfs API which offers a generic API for selecting the performance-profile of these automatic-mechanisms. Co-developed-by: Mark Pearson Signed-off-by: Mark Pearson Signed-off-by: Hans de Goede --- Changes in V1: - Moved from RFC to proposed patch - Added cool profile as requested - removed extra-profiles as no longer relevant .../ABI/testing/sysfs-platform_profile | 66 +++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-platform_profile diff --git a/Documentation/ABI/testing/sysfs-platform_profile b/Documentation/ABI/testing/sysfs-platform_profile new file mode 100644 index 000000000000..240bd3d7532b --- /dev/null +++ b/Documentation/ABI/testing/sysfs-platform_profile @@ -0,0 +1,66 @@ +Platform-profile selection (e.g. /sys/firmware/acpi/platform_profile) + +On modern systems the platform performance, temperature, fan and other +hardware related characteristics are often dynamically configurable. The +profile is often automatically adjusted to the load by some +automatic-mechanism (which may very well live outside the kernel). + +These auto platform-adjustment mechanisms often can be configured with +one of several 'platform-profiles', with either a bias towards low-power +consumption or towards performance (and higher power consumption and +thermals). + +The purpose of the platform_profile attribute is to offer a generic sysfs +API for selecting the platform-profile of these automatic-mechanisms. + +Note that this API is only for selecting the platform-profile, it is +NOT a goal of this API to allow monitoring the resulting performance +characteristics. Monitoring performance is best done with device/vendor +specific tools such as e.g. turbostat. + +Specifically when selecting a high-performance profile the actual achieved +performance may be limited by various factors such as: the heat generated +by other components, room temperature, free air flow at the bottom of a +laptop, etc. It is explicitly NOT a goal of this API to let userspace know +about any sub-optimal conditions which are impeding reaching the requested +performance level. + +Since numbers are a rather meaningless way to describe platform-profiles +this API uses strings to describe the various profiles. To make sure that +userspace gets a consistent experience when using this API this API +document defines a fixed set of profile-names. Drivers *must* map their +internal profile representation/names onto this fixed set. + +If for some reason there is no good match when mapping then a new profile-name +may be added. Drivers which wish to introduce new profile-names must: +1. Have very good reasons to do so. +2. Add the new profile-name to this document, so that future drivers which also + have a similar problem can use the same name. + +What: /sys/firmware/acpi/platform_profile_choices +Date: October 2020 +Contact: Hans de Goede +Description: + Reading this file gives a space separated list of profiles + supported for this device. + + Drivers must use the following standard profile-names: + + low-power: Emphasises low power consumption + cool: Emphasises cooler operation + quiet: Emphasises quieter operation + balanced: Balance between low power consumption + and performance + performance: Emphasises performance (and may lead to + higher temperatures and fan speeds) + + Userspace may expect drivers to offer at least several of these + standard profile-names. + +What: /sys/firmware/acpi/platform_profile +Date: October 2020 +Contact: Hans de Goede +Description: + Reading this file gives the current selected profile for this + device. Writing this file with one of the strings from + available_profiles changes the profile to the new value.