From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juri Lelli Subject: Re: [PATCH v5 1/8] Documentation: arm: define DT cpu capacity-dmips-mhz bindings Date: Wed, 15 Jun 2016 15:24:32 +0100 Message-ID: <20160615142432.GE5981@e106622-lin> References: <1465985877-18271-1-git-send-email-juri.lelli@arm.com> <1465985877-18271-2-git-send-email-juri.lelli@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Vincent Guittot Cc: linux-kernel , "linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , LAK , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Peter Zijlstra , Rob Herring , Mark Rutland , Russell King - ARM Linux , Sudeep Holla , Lorenzo Pieralisi , Catalin Marinas , Will Deacon , Morten Rasmussen , Dietmar Eggemann , Mark Brown , Sai Charan Gurrappadi , Pawel Moll , Ian Campbell , Kumar Gala , Maxime Ripard , Olof List-Id: devicetree@vger.kernel.org On 15/06/16 14:51, Vincent Guittot wrote: > On 15 June 2016 at 12:17, Juri Lelli wrote: [...] > > +========================================== > > +ARM CPUs capacity bindings > > +========================================== > > + > > +========================================== > > +1 - Introduction > > +========================================== > > + > > +ARM systems may be configured to have cpus with different power/performance > > +characteristics within the same chip. In this case, additional information > > +has to be made available to the kernel (the scheduler in particular) for > > not sure that it's worth mentioning the scheduler in particular here > OK. I can remove that bit. > > +it to be aware of such differences and take decisions accordingly. > > + [...] > > +========================================== > > +3 - capacity-dmips-mhz > > +========================================== > > + > > +capacity-dmips-mhz is an optional cpu node [1] property: u32 value > > +representing CPU capacity expressed in normalized DMIPS/MHz. At boot time, the > > +maximum frequency available to the cpu is then used to calculate the capacity > > +value internally used by the kernel. > > + > > +capacity-dmips-mhz property is all-or-nothing: if it is specified for a cpu > > +node, it has to be specified for every other cpu nodes, or the system will > > +fall back to the default capacity value for every CPU. If cpufreq is not > > +available, final capacities are calculated by directly using capacity-dmips- > > +mhz values (normalized w.r.t. the highest value found while parsing the DT). > > looks good to me > Great! Thanks for reviewing this. Best, - Juri -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html