Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753102Ab3H0J3h (ORCPT ); Tue, 27 Aug 2013 05:29:37 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:37270 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752111Ab3H0J3f (ORCPT ); Tue, 27 Aug 2013 05:29:35 -0400 Date: Tue, 27 Aug 2013 10:29:32 +0100 From: Mark Rutland To: Eduardo Valentin Cc: "swarren@wwwdotorg.org" , Pawel Moll , "ian.campbell@citrix.com" , "grant.likely@linaro.org" , "rob.herring@calxeda.com" , "linux@roeck-us.net" , "rui.zhang@intel.com" , "wni@nvidia.com" , "durgadoss.r@intel.com" , "linux-pm@vger.kernel.org" , "devicetree@vger.kernel.org" , "lm-sensors@lm-sensors.org" , "linux-kernel@vger.kernel.org" , "Rafael J. Wysocki" , Viresh Kumar , "cpufreq@vger.kernel.org" , "devicetree-discuss@lists.ozlabs.org" Subject: Re: [RFC PATCH 01/14] cpufreq: cpufreq-cpu0: add dt node parsing for 'cooling-zones' Message-ID: <20130827092931.GB19893@e106331-lin.cambridge.arm.com> References: <1377299755-5134-1-git-send-email-eduardo.valentin@ti.com> <1377299755-5134-2-git-send-email-eduardo.valentin@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1377299755-5134-2-git-send-email-eduardo.valentin@ti.com> Thread-Topic: [RFC PATCH 01/14] cpufreq: cpufreq-cpu0: add dt node parsing for 'cooling-zones' Accept-Language: en-GB, en-US Content-Language: en-US acceptlanguage: en-GB, en-US User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4391 Lines: 120 On Sat, Aug 24, 2013 at 12:15:42AM +0100, Eduardo Valentin wrote: > This patch changes the cpufreq-cpu0 driver to consider if > a cpu needs cooling (with cpufreq). In case the cooling is needed, > it can be flagged at the cpu0 device tree node, with the list > of zones property 'cooling-zones'. > > In case this list of zones is present, the driver will > load a cpufreq cooling device in the system. The cpufreq-cpu0 > driver is not interested in determining how the system should > be using the cooling device. The driver is responsible > only of loading the cooling device. > > Describing how the cooling device will be used can be > accomplished by setting up a thermal zone that references > and is composed by the cpufreq cooling device. > > Cc: "Rafael J. Wysocki" > Cc: Viresh Kumar > Cc: Grant Likely > Cc: Rob Herring > Cc: cpufreq@vger.kernel.org > Cc: linux-pm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Cc: devicetree-discuss@lists.ozlabs.org > Signed-off-by: Eduardo Valentin > --- > Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt | 4 ++++ > drivers/cpufreq/cpufreq-cpu0.c | 12 ++++++++++++ > 2 files changed, 16 insertions(+) > > diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt > index 051f764..add50f7 100644 > --- a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt > +++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt > @@ -15,6 +15,9 @@ Optional properties: > - clock-latency: Specify the possible maximum transition latency for clock, > in unit of nanoseconds. > - voltage-tolerance: Specify the CPU voltage tolerance in percentage. > +- cooling-zones: A list of thermal zones phandles. The generic cpu > + cooling (freq clipping) is loaded by the generic cpufreq-cpu0 driver > + in case the device tree node has this list. Bindings should not describe the behaviour of any kernel (and for that reason I'm not very keen on the current cpufreq-cpu0 binding document). Bindings should simply describe the hardware. This addition could instead be: - cooling-zones: a list of thermal zone phandles. However, as the thermal zone binding doesn't seem to have appeared by this patch, it should get moved later anyway... Thanks, Mark. > > Examples: > > @@ -33,6 +36,7 @@ cpus { > 198000 850000 > >; > clock-latency = <61036>; /* two CLK32 periods */ > + cooling-zones = <&cpu_thermal>; > }; > > cpu@1 { > diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c > index ad1fde2..ede6487 100644 > --- a/drivers/cpufreq/cpufreq-cpu0.c > +++ b/drivers/cpufreq/cpufreq-cpu0.c > @@ -20,6 +20,9 @@ > #include > #include > #include > +#include > +#include > +#include > > static unsigned int transition_latency; > static unsigned int voltage_tolerance; /* in percentage */ > @@ -28,6 +31,7 @@ static struct device *cpu_dev; > static struct clk *cpu_clk; > static struct regulator *cpu_reg; > static struct cpufreq_frequency_table *freq_table; > +static struct thermal_cooling_device *cdev; > > static int cpu0_verify_speed(struct cpufreq_policy *policy) > { > @@ -268,6 +272,13 @@ static int cpu0_cpufreq_probe(struct platform_device *pdev) > goto out_free_table; > } > > + /* > + * For now, just loading the cooling device; > + * thermal DT code takes care of matching them. > + */ > + if (of_find_property(np, "cooling-zones", NULL)) > + cdev = cpufreq_cooling_register(cpu_present_mask); > + > of_node_put(np); > of_node_put(parent); > return 0; > @@ -283,6 +294,7 @@ out_put_parent: > > static int cpu0_cpufreq_remove(struct platform_device *pdev) > { > + cpufreq_cooling_unregister(cdev); > cpufreq_unregister_driver(&cpu0_cpufreq_driver); > opp_free_cpufreq_table(cpu_dev, &freq_table); > > -- > 1.8.2.1.342.gfa7285d > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/