Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752468AbcD0XbC (ORCPT ); Wed, 27 Apr 2016 19:31:02 -0400 Received: from mail-pf0-f181.google.com ([209.85.192.181]:34976 "EHLO mail-pf0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751038AbcD0Xa7 (ORCPT ); Wed, 27 Apr 2016 19:30:59 -0400 Date: Wed, 27 Apr 2016 16:30:55 -0700 From: Eduardo Valentin To: Wei Ni Cc: thierry.reding@gmail.com, robh+dt@kernel.org, rui.zhang@intel.com, MLongnecker@nvidia.com, swarren@wwwdotorg.org, mikko.perttunen@kapsi.fi, linux-tegra@vger.kernel.org, linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 4/9] of: Add bindings of hw throttle for soctherm Message-ID: <20160427233054.GA26451@localhost.localdomain> References: <1461727554-15065-1-git-send-email-wni@nvidia.com> <1461727554-15065-5-git-send-email-wni@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1461727554-15065-5-git-send-email-wni@nvidia.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6798 Lines: 177 From: Eduardo Valentin To: Wei Ni Cc: thierry.reding@gmail.com, robh+dt@kernel.org, rui.zhang@intel.com, MLongnecker@nvidia.com, swarren@wwwdotorg.org, mikko.perttunen@kapsi.fi, linux-tegra@vger.kernel.org, linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Bcc: Subject: Re: [PATCH v2 4/9] of: Add bindings of hw throttle for soctherm Reply-To: In-Reply-To: <1461727554-15065-5-git-send-email-wni@nvidia.com> The patch title must say something about the fact that this is specific to nvidia thermal driver. On Wed, Apr 27, 2016 at 11:25:49AM +0800, Wei Ni wrote: > Add HW throttle configuration sub-node for soctherm, which > is used to describe the throttle event, and worked as a > cooling device. The "hot" type trip in thermal zone can > be bound to this cooling device, and trigger the throttle > function. > > Signed-off-by: Wei Ni > --- > .../bindings/thermal/nvidia,tegra124-soctherm.txt | 89 +++++++++++++++++++++- > 1 file changed, 87 insertions(+), 2 deletions(-) > > diff --git a/Documentation/devicetree/bindings/thermal/nvidia,tegra124-soctherm.txt b/Documentation/devicetree/bindings/thermal/nvidia,tegra124-soctherm.txt > index edebfa0a985e..dc337d139f49 100644 > --- a/Documentation/devicetree/bindings/thermal/nvidia,tegra124-soctherm.txt > +++ b/Documentation/devicetree/bindings/thermal/nvidia,tegra124-soctherm.txt > @@ -10,8 +10,14 @@ Required properties : > - compatible : For Tegra124, must contain "nvidia,tegra124-soctherm". > For Tegra132, must contain "nvidia,tegra132-soctherm". > For Tegra210, must contain "nvidia,tegra210-soctherm". > -- reg : Should contain 1 entry: > +- reg : Should contain at least 2 entries for each entry in reg-names: > - SOCTHERM register set > + - Tegra CAR register set: Required for Tegra124 and Tegra210. > + - CCROC register set: Required for Tegra132. > +- reg-names : Should contain at least 2 entries: > + - soctherm-reg > + - car-reg > + - ccroc-reg > - interrupts : Defines the interrupt used by SOCTHERM > - clocks : Must contain an entry for each entry in clock-names. > See ../clocks/clock-bindings.txt for details. > @@ -25,17 +31,44 @@ Required properties : > - #thermal-sensor-cells : Should be 1. See ./thermal.txt for a description > of this property. See for a > list of valid values when referring to thermal sensors. > +- throttle-cfgs: A sub-node which is a container of configuration for each > + hardware throttle events. These events can be set as cooling devices. > + * throttle events: Sub-nodes must be named as "light" or "heavy". > + Properties: > + - priority: Each throttles has its own throttle settings, so the SW need > + to set priorities for various throttle, the HW arbiter can select the > + final throttle settings. > + Bigger value indicates higher priority, In general, higher priority > + translates to lower target frequency. SW needs to ensure that critical > + thermal alarms are given higher priority, and ensure that there is > + no race if priority of two vectors is set to the same value. > + - cpu-throt-depth: This property is for Tegra124 and Tegra210. It is > + the throttling depth of pulse skippers, it's the percentage > + throttling. > + - cpu-throt-level: This property is only for Tegra132, it is the level > + of pulse skippers, which used to throttle clock frequencies. It > + indicates cpu clock throttling depth, and the depth can be programmed. > + Must set as following values: > + TEGRA_SOCTHERM_THROT_LEVEL_LOW, TEGRA_SOCTHERM_THROT_LEVEL_MED > + TEGRA_SOCTHERM_THROT_LEVEL_HIGH, TEGRA_SOCTHERM_THROT_LEVEL_NONE These properties are not generic properties. My understanding is that you must have vendor prefix in such case. Same applies to the new nodes. > + - #cooling-cells: Should be 1. This cooling device only support on/off state. > + See ./thermal.txt for a description of this property. > > Note: > - the "critical" type trip points will be set to SOC_THERM hardware as the > shut down temperature. Once the temperature of this thermal zone is higher > than it, the system will be shutdown or reset by hardware. > +- the "hot" type trip points will be set to SOC_THERM hardware as the throttle > +temperature. Once the the temperature of this thermal zone is higher > +than it, it will trigger the HW throttle event. > > Example : > > soctherm@700e2000 { > compatible = "nvidia,tegra124-soctherm"; > - reg = <0x0 0x700e2000 0x0 0x1000>; > + reg = <0x0 0x700e2000 0x0 0x600 /* SOC_THERM reg_base */ > + 0x0 0x60006000 0x0 0x400 /* CAR reg_base */ > + reg-names = "soctherm-reg", "car-reg"; > interrupts = ; > clocks = <&tegra_car TEGRA124_CLK_TSENSOR>, > <&tegra_car TEGRA124_CLK_SOC_THERM>; > @@ -44,6 +77,45 @@ Example : > reset-names = "soctherm"; > > #thermal-sensor-cells = <1>; > + > + throttle-cfgs { > + throttle_heavy: heavy { > + priority = <100>; > + cpu-throt-depth = <85>; > + > + #cooling-cells = <1>; > + }; > + throttle_light: light { > + priority = <80>; > + cpu-throt-depth = <50>; > + > + #cooling-cells = <1>; > + }; > + }; This is a sensor, which at the same time, has sub nodes that can be cooling devices. Is my understanding correct of what you are trying to do? > + }; > + > +Example: referring to Tegra132's "reg", "reg-names" and "throttle-cfgs" : > + > + soctherm@0,700e2000 { > + compatible = "nvidia,tegra132-soctherm"; > + reg = <0x0 0x700e2000 0x0 0x600 /* SOC_THERM reg_base */ > + 0x0 0x70040000 0x0 0x200>; /* CCROC reg_base */; > + reg-names = "soctherm-reg", "ccroc-reg"; > + > + throttle-cfgs { > + throttle_heavy: heavy { > + priority = <100>; > + cpu-throt-level = ; > + > + #cooling-cells = <1>; > + }; > + throttle_light: light { > + priority = <80>; > + cpu-throt-level = ; > + > + #cooling-cells = <1>; Could you please describe a little here what to expect of the above setup? > + }; > + }; > }; > > Example: referring to thermal sensors : > @@ -62,6 +134,19 @@ Example: referring to thermal sensors : > hysteresis = <1000>; > type = "critical"; > }; > + > + cpu_throttle_trip: throttle-trip { > + temperature = <100000>; > + hysteresis = <1000>; > + type = "hot"; > + }; > + }; > + > + cooling-maps { > + map0 { > + trip = <&cpu_throttle_trip>; > + cooling-device = <&throttle_heavy 1 1>; > + }; > }; > }; > }; > -- > 1.9.1 >