From patchwork Thu Mar 5 12:56:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amit Kucheria X-Patchwork-Id: 11421817 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9C8AC92A for ; Thu, 5 Mar 2020 12:57:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 743E3208C3 for ; Thu, 5 Mar 2020 12:57:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="EHt4DAgG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726524AbgCEM5A (ORCPT ); Thu, 5 Mar 2020 07:57:00 -0500 Received: from mail-pj1-f65.google.com ([209.85.216.65]:38511 "EHLO mail-pj1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726498AbgCEM47 (ORCPT ); Thu, 5 Mar 2020 07:56:59 -0500 Received: by mail-pj1-f65.google.com with SMTP id a16so2493187pju.3 for ; Thu, 05 Mar 2020 04:56:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=YPje9xcPYfIamEpUGoSH/TcUKQBJFPYwji3i7uk9SdI=; b=EHt4DAgGtc8ZWbbUms/Azd5KsSQkQH56Vwm8e9HTZaNCV+GsiFiy3wkfP5ymusF9FR q0c9pXbn2AcjIXTcxk2jNH4DAbYGqdRx2oQNY5Amh84vt9TRg/0GNanxvEUn4tb2YIKM +dvpOYTDs70oZiZ7dRe6W63hbHfh1nue/w/p0hUj8vX+qNLcFnQu6Ad5iGdPp4/IPGAf pjxLSUBkWc761aiD10tMXEOSFPCW5SE7O4WB5Qyc8eqtWIrLpK+K1TxFV4gk4qgKlZHU JAoj7XtOgIATfwwruZ8DQD4qWdT8URKd+LIsSbLG+59717l7WjnfhsnyEGzj1WK0DgIT 5sXA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=YPje9xcPYfIamEpUGoSH/TcUKQBJFPYwji3i7uk9SdI=; b=UXk8nDAcPb20DQHmbecHmjGCEuR2WnWSsOpjcXnMjeDHZEbCYaRfEoXaByQcbBmJLN 9dkO+kSqPVOeY2lbZv88suMQ6pgXklqtgvYhoWM0ShODCuZvxC380EqLnAdCxpX7gzKP c4HYTlBltVFiA7LIMZgI/oZrZa+Npap5iai9WsftDChn4u22v0bZPjMzLUFrzlJi5Xdt lIHaTCOu1L+2znj500t+H8WYxKQBXHc3v+jKQApx5NDz4YH5NfZBYB4SZGMTi1mnVmmL Na4/k1fmVBh+Ne+/3QQLDH1UD/H+IXsiS/qX/oxMgHedbx7obPcSrDOTNCcz0M+06FWt WZuQ== X-Gm-Message-State: ANhLgQ32xx0s3hULBBOsJELCwp+5hZT9xOLkCgAueo/Kgws9gYEbvqqM 8CTs4/mxShtRIMWQMbnqTjA2Sg== X-Google-Smtp-Source: ADFU+vvPYdi7ZwmB0U0Sj6BPoR9D3pE/yA0/hXZrIVssSPjgpFaycsmnvIxiOf3TYBYNpoG36JlFLg== X-Received: by 2002:a17:90a:bf09:: with SMTP id c9mr7953201pjs.96.1583413016741; Thu, 05 Mar 2020 04:56:56 -0800 (PST) Received: from localhost ([103.195.202.216]) by smtp.gmail.com with ESMTPSA id r12sm32030259pgu.93.2020.03.05.04.56.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Mar 2020 04:56:55 -0800 (PST) From: Amit Kucheria To: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, swboyd@chromium.org, mka@chromium.org, daniel.lezcano@linaro.org, Amit Kucheria , Zhang Rui Cc: linux-pm@vger.kernel.org, devicetree@vger.kernel.org Subject: [PATCH v2 2/3] dt-bindings: thermal: Add yaml bindings for thermal cooling-devices Date: Thu, 5 Mar 2020 18:26:42 +0530 Message-Id: <9a2052ee2afa43048bd4e2594d015fca6bbf5116.1583412540.git.amit.kucheria@linaro.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: References: MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org As part of moving the thermal bindings to YAML, split it up into 3 bindings: thermal sensors, cooling devices and thermal zones. The property #cooling-cells is required in each device that acts as a cooling device - whether active or passive. So any device that can throttle its performance to passively reduce heat dissipation (e.g. cpus, gpus) and any device that can actively dissipate heat at different levels (e.g. fans) will contain this property. Signed-off-by: Amit Kucheria --- .../thermal/thermal-cooling-devices.yaml | 114 ++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml diff --git a/Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml b/Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml new file mode 100644 index 0000000000000..4745ea4b41ae7 --- /dev/null +++ b/Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml @@ -0,0 +1,114 @@ +# SPDX-License-Identifier: (GPL-2.0) +# Copyright 2020 Linaro Ltd. +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/thermal/thermal-cooling-devices.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Thermal cooling device binding + +maintainers: + - Amit Kucheria + +description: | + Thermal management is achieved in devicetree by describing the sensor hardware + and the software abstraction of cooling devices and thermal zones required to + take appropriate action to mitigate thermal overload. + + The following node types are used to completely describe a thermal management + system in devicetree: + - thermal-sensor: device that measures temperature, has SoC-specific bindings + - cooling-device: device used to dissipate heat either passively or artively + - thermal-zones: a container of the following node types used to describe all + thermal data for the platform + + This binding describes the cooling devices. + + There are essentially two ways to provide control on power dissipation: + - Passive cooling: by means of regulating device performance. A typical + passive cooling mechanism is a CPU that has dynamic voltage and frequency + scaling (DVFS), and uses lower frequencies as cooling states. + - Active cooling: by means of activating devices in order to remove the + dissipated heat, e.g. regulating fan speeds. + + Any cooling device has a range of cooling states (i.e. different levels of + heat dissipation). They also have a way to determine the state of cooling in + which the device is. For example, a fan's cooling states correspond to the + different fan speeds possible. Cooling states are referred to by single + unsigned integers, where larger numbers mean greater heat dissipation. The + precise set of cooling states associated with a device should be defined in + a particular device's binding. + +properties: + "#cooling-cells": + description: + Must be 2, in order to specify minimum and maximum cooling state used in + the cooling-maps reference. The first cell is the minimum cooling state + and the second cell is the maximum cooling state requested. + const: 2 + +examples: + - | + #include + #include + + // Example 1: Cpufreq cooling device on CPU0 + cpus { + #address-cells = <2>; + #size-cells = <0>; + + CPU0: cpu@0 { + device_type = "cpu"; + compatible = "qcom,kryo385"; + reg = <0x0 0x0>; + enable-method = "psci"; + cpu-idle-states = <&LITTLE_CPU_SLEEP_0 + &LITTLE_CPU_SLEEP_1 + &CLUSTER_SLEEP_0>; + capacity-dmips-mhz = <607>; + dynamic-power-coefficient = <100>; + qcom,freq-domain = <&cpufreq_hw 0>; + #cooling-cells = <2>; + next-level-cache = <&L2_0>; + L2_0: l2-cache { + compatible = "cache"; + next-level-cache = <&L3_0>; + L3_0: l3-cache { + compatible = "cache"; + }; + }; + }; + + /* ... */ + + }; + + /* ... */ + + thermal-zones { + cpu0-thermal { + polling-delay-passive = <250>; + polling-delay = <1000>; + + thermal-sensors = <&tsens0 1>; + + trips { + cpu0_alert0: trip-point0 { + temperature = <90000>; + hysteresis = <2000>; + type = "passive"; + }; + }; + + cooling-maps { + map0 { + trip = <&cpu0_alert0>; + cooling-device = <&CPU0 THERMAL_NO_LIMIT + THERMAL_NO_LIMIT>; + }; + }; + }; + + /* ... */ + }; +...