From patchwork Fri Dec 11 02:06:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Pearson X-Patchwork-Id: 342901 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, 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 EC0FCC4167B for ; Fri, 11 Dec 2020 02:15:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9662123DE4 for ; Fri, 11 Dec 2020 02:15:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389516AbgLKCOx (ORCPT ); Thu, 10 Dec 2020 21:14:53 -0500 Received: from mail1.bemta24.messagelabs.com ([67.219.250.3]:34795 "EHLO mail1.bemta24.messagelabs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726550AbgLKCOj (ORCPT ); Thu, 10 Dec 2020 21:14:39 -0500 Received: from [100.112.128.122] (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256 bits)) by server-3.bemta.az-a.us-west-2.aws.symcld.net id 47/DD-50495-2F4D2DF5; Fri, 11 Dec 2020 02:09:54 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprDKsWRWlGSWpSXmKPExsWSLveKXffTlUv xBp//iFnsvy5h0bXQwGLh/VOsFl+/3Wa3eHN8OpPF8n39jBZNnU1sFp87JrNYrN7zgtli7Zd5 bBZnTl9ideD2mDRzBrPHzll32T1+bVvD4rF5hZbHvJOBHj1tm5g83u+7yuax5Wo7i8fnTXIBn FGsmXlJ+RUJrBldHZ2sBee1K55vWMnUwHhFtYuRk0NI4D+jxL9utS5GLiD7AaPE/utvWEESbA LaElu2/GLrYuTgEBGQkfiw1hOkhllgK5PEyX07wWqEBRIlNrxtZQexWQRUJbb+WQBm8wrYSPS 0zmYEsSUE5CWe9i5nBrE5gWrOdD1mgVisInH/wRI2iHpBiZMzn4DFmYHqm7fOZoawJSQOvnjB DDNnzsWpUHaCxLKXd5gnMArMQtI+C0n7LCTtCxiZVzFaJBVlpmeU5CZm5ugaGhjoGhoa6RoaG +oaGZrpJVbpJuqVFuuWpxaX6BrpJZYX6xVX5ibnpOjlpZZsYgRGWkpB840djLPefNA7xCjJwa Qkyvt48qV4Ib6k/JTKjMTijPii0pzU4kOMMhwcShK86peBcoJFqempFWmZOcCoh0lLcPAoifD mgKR5iwsSc4sz0yFSpxgVpcR5lUESAiCJjNI8uDZYornEKCslzMvIwMAgxFOQWpSbWYIq/4pR nINRSZh38yWgKTyZeSVw018BLWYCWsxz6TzI4pJEhJRUA5PubD6Ncwuv/T6z92X7db/e7EY9f 7t79oUB5pbdarJC7NvqudU1n0yaUneB6ZgN1+HS+VE9KTLCtqy/z22W/rix93RCZcZJBvlA+S u//Tek6UxtcuJkaoxTuRW232nXqdZkh3Nd7i/1DQXaPBa9E1hYz7/xzkHZ2tpwLV+tGRIrPOM nFVdFLzwicdRU/ne9bKNlybbaoPcs6ma7lp/UtHgntUVNzbuK5+a+uWGXjl6+sdMy5xbPlFAb +9rItJtmqltvKGbPnf2v+vLbLTb+RvyLbl9TyLuWqf1s37fmn+U1jZrTGWZsuLK69b2BsW5XQ mhq9WyX3eaRU9dF2b34e/PX9Bl7dLifbvQXPFImrMRSnJFoqMVcVJwIANEFbmqvAwAA X-Env-Sender: markpearson@lenovo.com X-Msg-Ref: server-7.tower-326.messagelabs.com!1607652592!24750!1 X-Originating-IP: [103.30.234.7] X-SYMC-ESS-Client-Auth: outbound-route-from=pass X-StarScan-Received: X-StarScan-Version: 9.60.3; banners=-,-,- X-VirusChecked: Checked Received: (qmail 28831 invoked from network); 11 Dec 2020 02:09:54 -0000 Received: from unknown (HELO lenovo.com) (103.30.234.7) by server-7.tower-326.messagelabs.com with ECDHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 11 Dec 2020 02:09:54 -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 302FD1D359FEFC2F5C5E; Fri, 11 Dec 2020 10:09:48 +0800 (CST) Received: from localhost.home (10.64.86.16) 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; Thu, 10 Dec 2020 18:09:41 -0800 From: Mark Pearson To: CC: , , , , , , , , , , , Subject: [PATCH v6 1/3] Documentation: Add documentation for new platform_profile sysfs attribute Date: Thu, 10 Dec 2020 21:06:28 -0500 Message-ID: <20201211020630.305905-1-markpearson@lenovo.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: References: MIME-Version: 1.0 X-Originating-IP: [10.64.86.16] 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-acpi@vger.kernel.org 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). 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 v2: - updated to rst format Changes in v3, v4, v5 - version bump along with rest of patch series Changes in v6: - Split sysfs-platform_profile.rs into ABI text and then admin guide in userspace-api section. Hope this is correct - I'm guessing a bit. .../ABI/testing/sysfs-platform_profile | 24 +++++++++++ Documentation/userspace-api/index.rst | 1 + .../userspace-api/sysfs-platform_profile.rst | 43 +++++++++++++++++++ 3 files changed, 68 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-platform_profile create mode 100644 Documentation/userspace-api/sysfs-platform_profile.rst diff --git a/Documentation/ABI/testing/sysfs-platform_profile b/Documentation/ABI/testing/sysfs-platform_profile new file mode 100644 index 000000000000..5ac14268585f --- /dev/null +++ b/Documentation/ABI/testing/sysfs-platform_profile @@ -0,0 +1,24 @@ +What: /sys/firmware/acpi/platform_profile_choices +Date: October 2020 +Contact: Hans de Goede +Description: This file contains a space-separated list of profiles supported for this device. + + Drivers must use the following standard profile-names: + + ============ ============================================ + low-power Low power consumption + cool Cooler operation + quiet Quieter operation + balanced Balance between low power consumption and performance + performance High performance operation + ============ ============================================ + + Userspace may expect drivers to offer more than one 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. diff --git a/Documentation/userspace-api/index.rst b/Documentation/userspace-api/index.rst index acd2cc2a538d..d29b020e5622 100644 --- a/Documentation/userspace-api/index.rst +++ b/Documentation/userspace-api/index.rst @@ -24,6 +24,7 @@ place where this information is gathered. ioctl/index iommu media/index + sysfs-platform_profile .. only:: subproject and html diff --git a/Documentation/userspace-api/sysfs-platform_profile.rst b/Documentation/userspace-api/sysfs-platform_profile.rst new file mode 100644 index 000000000000..56639d218003 --- /dev/null +++ b/Documentation/userspace-api/sysfs-platform_profile.rst @@ -0,0 +1,43 @@ +===================================================================== +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 +operation or towards performance. + +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 on their own cannot represent the multiple variables that a +profile will adjust (power consumption, heat generation, etc) this API +uses strings to describe the various profiles. To make sure that userspace +gets a consistent experience the sysfs-platform_profile ABI document defines +a fixed set of profile names. Drivers *must* map their internal profile +representation onto this fixed set. + +If 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. Explain why the existing profile names canot be used. + 2. Add the new profile name, along with a clear description of the + expected behaviour, to the sysfs-platform_profile ABI documentation. + +