From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mason Subject: Re: Plain DFS (no voltage scaling) Date: Wed, 3 Feb 2016 19:25:56 +0100 Message-ID: <56B24634.6060001@free.fr> References: <56B11B67.3090600@free.fr> <20160203021052.GK31828@vireshk> <56B21E2E.1070606@free.fr> <20160203161428.GJ3469@vireshk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: Received: from smtp4-g21.free.fr ([212.27.42.4]:52416 "EHLO smtp4-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965121AbcBCS0H (ORCPT ); Wed, 3 Feb 2016 13:26:07 -0500 In-Reply-To: <20160203161428.GJ3469@vireshk> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Viresh Kumar Cc: Linux PM , "Rafael J. Wysocki" , Linux ARM On 03/02/2016 17:14, Viresh Kumar wrote: > On 03-02-16, 16:35, Mason wrote: >> On 03/02/2016 03:10, Viresh Kumar wrote: >>> On 02-02-16, 22:11, Mason wrote: >>>> Hello, >>>> >>>> I plan to enable the on-demand governor on the tango platform: >>>> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/tango4-smp8758.dtsi >>>> >>>> I found the cpufreq-dt binding doc: >>>> >>>> https://www.kernel.org/doc/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt >>>> https://www.kernel.org/doc/Documentation/devicetree/bindings/opp/opp.txt >>>> >>>> Something is not clear to me: >>>> >>>> If my platform cannot scale the voltage, what information >>>> should I put in the voltage part of the DT? >>> >>> Wouldn't matter if there is no regulator. i.e. you should keep 0, but >>> even if they have something non-zero, core code will ignore it. But >>> yeah, it makes sense to keep it zero. >> >> Hmmm, I am missing something obvious. >> >> My config contains: >> >> CONFIG_CPU_FREQ=y >> CONFIG_CPU_FREQ_GOV_COMMON=y >> CONFIG_CPU_FREQ_STAT=y >> CONFIG_CPU_FREQ_STAT_DETAILS=y >> CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y >> CONFIG_CPU_FREQ_GOV_PERFORMANCE=y >> CONFIG_CPU_FREQ_GOV_ONDEMAND=y >> CONFIG_CPUFREQ_DT=y >> >> Yet, neither dt_cpufreq_probe() nor cpufreq_init() are being called. >> >> Could someone please point to my mistake? > > You need to create a platform device to get cpufreq-dt driver probed. > Check other users.. The sunxi guys pointed me in the right direction. http://lxr.free-electrons.com/source/arch/arm/mach-sunxi/sunxi.c#L20 Why isn't there a compatible string like other drivers? Such as compatible = "cpufreq-dt" which would enable cpufreq on the platform? Regards. From mboxrd@z Thu Jan 1 00:00:00 1970 From: slash.tmp@free.fr (Mason) Date: Wed, 3 Feb 2016 19:25:56 +0100 Subject: Plain DFS (no voltage scaling) In-Reply-To: <20160203161428.GJ3469@vireshk> References: <56B11B67.3090600@free.fr> <20160203021052.GK31828@vireshk> <56B21E2E.1070606@free.fr> <20160203161428.GJ3469@vireshk> Message-ID: <56B24634.6060001@free.fr> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 03/02/2016 17:14, Viresh Kumar wrote: > On 03-02-16, 16:35, Mason wrote: >> On 03/02/2016 03:10, Viresh Kumar wrote: >>> On 02-02-16, 22:11, Mason wrote: >>>> Hello, >>>> >>>> I plan to enable the on-demand governor on the tango platform: >>>> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/tango4-smp8758.dtsi >>>> >>>> I found the cpufreq-dt binding doc: >>>> >>>> https://www.kernel.org/doc/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt >>>> https://www.kernel.org/doc/Documentation/devicetree/bindings/opp/opp.txt >>>> >>>> Something is not clear to me: >>>> >>>> If my platform cannot scale the voltage, what information >>>> should I put in the voltage part of the DT? >>> >>> Wouldn't matter if there is no regulator. i.e. you should keep 0, but >>> even if they have something non-zero, core code will ignore it. But >>> yeah, it makes sense to keep it zero. >> >> Hmmm, I am missing something obvious. >> >> My config contains: >> >> CONFIG_CPU_FREQ=y >> CONFIG_CPU_FREQ_GOV_COMMON=y >> CONFIG_CPU_FREQ_STAT=y >> CONFIG_CPU_FREQ_STAT_DETAILS=y >> CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y >> CONFIG_CPU_FREQ_GOV_PERFORMANCE=y >> CONFIG_CPU_FREQ_GOV_ONDEMAND=y >> CONFIG_CPUFREQ_DT=y >> >> Yet, neither dt_cpufreq_probe() nor cpufreq_init() are being called. >> >> Could someone please point to my mistake? > > You need to create a platform device to get cpufreq-dt driver probed. > Check other users.. The sunxi guys pointed me in the right direction. http://lxr.free-electrons.com/source/arch/arm/mach-sunxi/sunxi.c#L20 Why isn't there a compatible string like other drivers? Such as compatible = "cpufreq-dt" which would enable cpufreq on the platform? Regards.