From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758498Ab2EBFMs (ORCPT ); Wed, 2 May 2012 01:12:48 -0400 Received: from na3sys009aog119.obsmtp.com ([74.125.149.246]:43326 "EHLO na3sys009aog119.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756312Ab2EBFMo convert rfc822-to-8bit (ORCPT ); Wed, 2 May 2012 01:12:44 -0400 MIME-Version: 1.0 In-Reply-To: <87wr4wriq3.fsf@ti.com> References: <1335462041-4949-1-git-send-email-j-keerthy@ti.com> <20120426191159.GA9415@sirena.org.uk> <20120427175657.GP18260@opensource.wolfsonmicro.com> <87397o3n4y.fsf@ti.com> <20120430095429.GB3170@opensource.wolfsonmicro.com> <87wr4wriq3.fsf@ti.com> Date: Wed, 2 May 2012 10:34:29 +0530 Message-ID: Subject: Re: [PATCH V3 00/10] PM: Create the AVS(Adaptive Voltage Scaling) From: "J, KEERTHY" To: Kevin Hilman Cc: Mark Brown , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, rjw@sisk.pl, linux-kernel@vger.kernel.org, linux-pm@lists.linux-foundation.org, j-pihet@ti.com, durgadoss.r@intel.com Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 1, 2012 at 3:21 AM, Kevin Hilman wrote: > Mark Brown writes: > >> On Fri, Apr 27, 2012 at 02:01:17PM -0700, Kevin Hilman wrote: >>> Mark Brown writes: >> >>> > But presumably these things should integrate somehow - for example, >>> > should devfreq and cpufreq be providing inputs into what AVS is doing, >>> > and if so how? >> >>> The way it is currently designed, cpufreq/devfreq/regulator layers don't >>> need to know about AVS. >> >> Yes, and that was a part of my concern, but see below. >> >>> The higher-level layers only know about the "nominal" voltage.  AVS >>> hardware does automatic, adaptive, micro-adjustments around that nominal >>> voltage, and these micro-adjustments are managed by the AVS hardware >>> sending commands to the PMIC.  (specifically, on OMAP, the AVS sensors >>> provide inputs to the voltage processor (VP) which provide inputs to the >>> voltage controller (VC) which sends commands to the PMIC[1].) >> >> Right, that's what I'd understood it to be. >> >>> The driver proposed here is primarily for initializing the various >>> parameters/sensitivity/etc. of the AVS hardware, but the actual voltage >>> adjustments are done in hardware by VC/VP. >> >> It's not just a driver, though - it's also creating this power/avs >> thing, though now I look at the code rather than just its shape there's >> not actually an abstraction being added here, it's mostly just straight >> code motion of the arch/arm code that's there already.  The changelog >> and the shape of the code make it sound like this is intended to be >> somewhat generic when really it's providing some OMAP specific tuning >> for the device which is much less of a concern. >> >> I guess for now it's probably OK to just clarify in the documentation >> and say that whoever adds the second driver has to work on making this >> generic :) > > Agreed. > > In a different thread (which I can't seem to find now) we discussed this > as well, so it just sounds like the changelog should clarify this a bit > better. Kevin/Mark, Thanks for the feedback. I will add more documentation to clarify this aspect. Please let me know if there are any more things to be taken care of in this patch set. > > Kevin > >> This does also sound rather like it's in a similar area to the current >> management work which Durgadoss R (CCed) was working on, though with a >> slightly different application and in the OMAP case it's pretty much all >> hidden in the external processor. > -- Regards and Thanks, Keerthy From mboxrd@z Thu Jan 1 00:00:00 1970 From: "J, KEERTHY" Subject: Re: [PATCH V3 00/10] PM: Create the AVS(Adaptive Voltage Scaling) Date: Wed, 2 May 2012 10:34:29 +0530 Message-ID: References: <1335462041-4949-1-git-send-email-j-keerthy@ti.com> <20120426191159.GA9415@sirena.org.uk> <20120427175657.GP18260@opensource.wolfsonmicro.com> <87397o3n4y.fsf@ti.com> <20120430095429.GB3170@opensource.wolfsonmicro.com> <87wr4wriq3.fsf@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <87wr4wriq3.fsf@ti.com> Sender: linux-omap-owner@vger.kernel.org To: Kevin Hilman Cc: Mark Brown , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, rjw@sisk.pl, linux-kernel@vger.kernel.org, linux-pm@lists.linux-foundation.org, j-pihet@ti.com, durgadoss.r@intel.com List-Id: linux-pm@vger.kernel.org On Tue, May 1, 2012 at 3:21 AM, Kevin Hilman wrote: > Mark Brown writes: > >> On Fri, Apr 27, 2012 at 02:01:17PM -0700, Kevin Hilman wrote: >>> Mark Brown writes: >> >>> > But presumably these things should integrate somehow - for exampl= e, >>> > should devfreq and cpufreq be providing inputs into what AVS is d= oing, >>> > and if so how? >> >>> The way it is currently designed, cpufreq/devfreq/regulator layers = don't >>> need to know about AVS. >> >> Yes, and that was a part of my concern, but see below. >> >>> The higher-level layers only know about the "nominal" voltage. =A0A= VS >>> hardware does automatic, adaptive, micro-adjustments around that no= minal >>> voltage, and these micro-adjustments are managed by the AVS hardwar= e >>> sending commands to the PMIC. =A0(specifically, on OMAP, the AVS se= nsors >>> provide inputs to the voltage processor (VP) which provide inputs t= o the >>> voltage controller (VC) which sends commands to the PMIC[1].) >> >> Right, that's what I'd understood it to be. >> >>> The driver proposed here is primarily for initializing the various >>> parameters/sensitivity/etc. of the AVS hardware, but the actual vol= tage >>> adjustments are done in hardware by VC/VP. >> >> It's not just a driver, though - it's also creating this power/avs >> thing, though now I look at the code rather than just its shape ther= e's >> not actually an abstraction being added here, it's mostly just strai= ght >> code motion of the arch/arm code that's there already. =A0The change= log >> and the shape of the code make it sound like this is intended to be >> somewhat generic when really it's providing some OMAP specific tunin= g >> for the device which is much less of a concern. >> >> I guess for now it's probably OK to just clarify in the documentatio= n >> and say that whoever adds the second driver has to work on making th= is >> generic :) > > Agreed. > > In a different thread (which I can't seem to find now) we discussed t= his > as well, so it just sounds like the changelog should clarify this a b= it > better. Kevin/Mark, Thanks for the feedback. I will add more documentation to clarify this aspect. Please let me know if there are any more things to be taken care of in this patch set. > > Kevin > >> This does also sound rather like it's in a similar area to the curre= nt >> management work which Durgadoss R (CCed) was working on, though with= a >> slightly different application and in the OMAP case it's pretty much= all >> hidden in the external processor. > --=20 Regards and Thanks, Keerthy -- To unsubscribe from this list: send the line "unsubscribe linux-omap" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: j-keerthy@ti.com (J, KEERTHY) Date: Wed, 2 May 2012 10:34:29 +0530 Subject: [PATCH V3 00/10] PM: Create the AVS(Adaptive Voltage Scaling) In-Reply-To: <87wr4wriq3.fsf@ti.com> References: <1335462041-4949-1-git-send-email-j-keerthy@ti.com> <20120426191159.GA9415@sirena.org.uk> <20120427175657.GP18260@opensource.wolfsonmicro.com> <87397o3n4y.fsf@ti.com> <20120430095429.GB3170@opensource.wolfsonmicro.com> <87wr4wriq3.fsf@ti.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, May 1, 2012 at 3:21 AM, Kevin Hilman wrote: > Mark Brown writes: > >> On Fri, Apr 27, 2012 at 02:01:17PM -0700, Kevin Hilman wrote: >>> Mark Brown writes: >> >>> > But presumably these things should integrate somehow - for example, >>> > should devfreq and cpufreq be providing inputs into what AVS is doing, >>> > and if so how? >> >>> The way it is currently designed, cpufreq/devfreq/regulator layers don't >>> need to know about AVS. >> >> Yes, and that was a part of my concern, but see below. >> >>> The higher-level layers only know about the "nominal" voltage. ?AVS >>> hardware does automatic, adaptive, micro-adjustments around that nominal >>> voltage, and these micro-adjustments are managed by the AVS hardware >>> sending commands to the PMIC. ?(specifically, on OMAP, the AVS sensors >>> provide inputs to the voltage processor (VP) which provide inputs to the >>> voltage controller (VC) which sends commands to the PMIC[1].) >> >> Right, that's what I'd understood it to be. >> >>> The driver proposed here is primarily for initializing the various >>> parameters/sensitivity/etc. of the AVS hardware, but the actual voltage >>> adjustments are done in hardware by VC/VP. >> >> It's not just a driver, though - it's also creating this power/avs >> thing, though now I look at the code rather than just its shape there's >> not actually an abstraction being added here, it's mostly just straight >> code motion of the arch/arm code that's there already. ?The changelog >> and the shape of the code make it sound like this is intended to be >> somewhat generic when really it's providing some OMAP specific tuning >> for the device which is much less of a concern. >> >> I guess for now it's probably OK to just clarify in the documentation >> and say that whoever adds the second driver has to work on making this >> generic :) > > Agreed. > > In a different thread (which I can't seem to find now) we discussed this > as well, so it just sounds like the changelog should clarify this a bit > better. Kevin/Mark, Thanks for the feedback. I will add more documentation to clarify this aspect. Please let me know if there are any more things to be taken care of in this patch set. > > Kevin > >> This does also sound rather like it's in a similar area to the current >> management work which Durgadoss R (CCed) was working on, though with a >> slightly different application and in the OMAP case it's pretty much all >> hidden in the external processor. > -- Regards and Thanks, Keerthy