On 12/28/2017 10:07 AM, Viresh Kumar wrote: > On 27-12-17, 15:54, Rob Herring wrote: >> On Wed, Dec 27, 2017 at 2:56 AM, Viresh Kumar <viresh.ku...@linaro.org> >> wrote: >>> On 26-12-17, 14:29, Rob Herring wrote: >>>> On Mon, Dec 18, 2017 at 03:51:30PM +0530, Viresh Kumar wrote: >>> >>>>> +On some platforms the exact frequency or voltage may be hidden from the >>>>> OS by >>>>> +the firmware and the "opp-hz" or the "opp-microvolt" properties may >>>>> contain >>>>> +magic values that represent the frequency or voltage in a firmware >>>>> dependent >>>>> +way, for example an index of an array in the firmware. >>>> >>>> I'm still not convinced this is a good idea. >>> >>> You were kind-of a few days back :) >>> >>> lkml.kernel.org/r/CAL_JsqK-qtAaM_Ou5NtxcWR3F_q=8rmpjum-vqgtkhbtwe5...@mail.gmail.com >> >> Yeah, well that was before Stephen said anything. >> >>> So here is the deal: >>> >>> - I proposed "domain-performance-state" property for this stuff >>> initially. >>> - But Kevin didn't like that and proposed reusing "opp-hz" and >>> "opp-microvolt", which we all agreed to multiple times.. >>> - And we are back to the same discussion now and its painful and time >>> killing for all of us. >> >> There's bigger issues than where we put magic values as I raised in >> the other patch. >> >>> TBH, I don't have too strong preferences about any of the suggestions >>> you guys have and I need you guys to tell me what binding changes to >>> do here and I will do that. >>> >>>> If you have firmware >>>> partially managing things, then I think we should have platform specific >>>> bindings or drivers. >>> >>> What about the initial idea then, like "performance-state" for the >>> power domains ? All platforms will anyway replicate that binding only. >> >> I don't really know. I don't really care either. I'll probably go >> along with what everyone agrees to, but the only one I see any >> agreement from is Ulf. Also, it is pretty vague as to what platforms >> will use this. You claimed you can support QCom scenarios, but there's >> really no evidence that that is true. > > Well, I sent out the code few days back based on these bindings and everyone > can > see how these bindings will get used now. > >> What I don't want to see is this >> merged and then we need something more yet again in a few months for >> another platform. > > Sure, I get your concerns. > > So what we need now is: > > - Stephen to start responding and clarify all the doubts he had as being > silent > isn't helping. > > - Or Rajendra to post patches which can prove that this is usable. The last > time > I had a chat with him, he confirmed that he will post patches after 4.15-rc1 > and he should have posted them by now, but he didn't :(
I would want to reiterate what I have been saying for a while, that for these patches to be usable on any qualcomm platform completely we need support to associate multiple power-domains to a single device which is missing today. The last time this came up during a discussion at connect, I believe the understanding was to get this (performance state support) merged *after* we decide how to support multiple powerdomains per device. What I have been testing with these patches is to move a single user (MMC, which BTW does not have to put requests on multiple powerdomains) to use this solution on a db820c (msm8996) device. Getting this merged now can open up issues for other devices (which can't move to this solution) since MMC alone would put requests to pull a *common* rail up/down while others can't. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
