From mboxrd@z Thu Jan 1 00:00:00 1970 From: Viresh Kumar Subject: Re: [PATCH V6 1/9] PM / OPP: Introduce "power-domain-opp" property Date: Mon, 8 May 2017 12:41:46 +0530 Message-ID: <20170508071146.GG17010@vireshk-i7> References: <025acedb263eaa6089d354d9630214ada8013990.1493203884.git.viresh.kumar@linaro.org> <20170428204803.plu467okibtxga4d@rob-hp-laptop> <20170508041511.GB17010@vireshk-i7> 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: Rajendra Nayak Cc: Kevin Hilman , Rob Herring , Rafael Wysocki , ulf.hansson-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, Viresh Kumar , Nishanth Menon , Stephen Boyd , linaro-kernel-cunTk1MwBs8s++Sfvej+rw@public.gmane.org, linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Vincent Guittot , lina.iyer-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, sudeep.holla-5wv7dgnIgG8@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org I had a long chat with Rajendra offline and clarified few things.. On 08-05-17, 11:06, Rajendra Nayak wrote: > On 05/08/2017 09:45 AM, Viresh Kumar wrote: > > On 06-05-17, 11:58, Kevin Hilman wrote: > >> I had the same question. Seems the same comment about an abstract > >> "index" is needed for voltage also. > > > > Why should we do that? Here are the cases that I had in mind while writing this: > > > > - DT only contains the performance-index and nothing else (i.e. voltages aren't > > exposed). > > > > We wouldn't be required to fill the microvolt property as it is optional. > > So the performance-index is specified in opp-hz property? Yes, but in the OPP table of the power-domain and not the device. The device can still have its own OPP table with normal freq/voltage values (for a separate regulator). > What if the microcontroller firmware maps the performance-index to voltage but > expects linux to scale the frequency? As you clarified on the chat, you were talking about the device here. It isn't a problem as we will have two separate tables here, one for the device and one for the domain. -- viresh -- 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