Hi! Here is my proposal for the PM constraints micro-conf RFP, as e-mailed today: Session title: A New Model for the System and Devices Latency Name of microconference (if applicable): PM constraints micro-conf, led by Mark Gross Abstract: Due to the nature of the new SoC architectures the Power Management needs a new model for the various system latencies. The talk presents: . the concepts of system, devices, wake-up and resume latencies, . the recent changes in the devices framework for the latency, why and how to make it generic, . the link with the other PM QoS frameworks: thermal, cpuidle, . the recent changes in the ARM/OMAP platform code for the system latency, . the problems encountered while modelling and measuring the various latencies, . a proposal on the model and on the way to implement it, . the planned changes in the device framework, the platform code and the APIs. This talk is oriented towards Linux power management developers. The goal is to agree on a framework implementation and the interfaces within the kernel and with the user space. Experience: Jean Pihet, NewOldBits.com Jean Pihet is working with embedded Linux since many years now, for companies like Texas Instruments, MontaVista, Motorola and Philips. Recently NewOldBits.com has been founded to provide high quality consulting services. The area of work is mainly OMAP Power Management, tracing and profiling tools (perf, ftrace, oprofile...) for recent ARM cores. Kind regards, Jean On Tue, May 15, 2012 at 7:34 AM, Valentin, Eduardo <eduardo.valentin@xxxxxx> wrote: > FYI, > > I will submit later today, something like this: > " > Abstract > > The thermal challenge is to design an end-product with high > performance while keeping the junction temperature of the IC > components used on this product within their limitations and which > does not present a thermal discomfort for the user. OMAP4/OMAP5 System > on Chips, operating at highest Operating Performance Points (OPP), is > a powerful mobile applications processor. However operating at higher > voltage and higher frequency in a sustained manner may cause thermal > limits to be exceeded, both for silicon and user comfort. We propose a > new framework to model per device power constraints, for containment > of thermal limitations across major heat sources of a end-product > device, e.g. LCD, CPU, charging, etc. The framework shall facilitate > the power and thermal management performed by governor and policies, > depending on device context and use case knowledge. > > Authors > > Eduardo Valentin, System Software Engineer at Texas Instruments, > working on OMAP Linux kernel, previously a working on power management > in maemo for Nokia. > > > On Tue, May 15, 2012 at 8:06 AM, Valentin, Eduardo > <eduardo.valentin@xxxxxx> wrote: >> Benoit, >> >> On Mon, May 14, 2012 at 8:11 PM, Cousson, Benoit <b-cousson@xxxxxx> wrote: >>> Hi Jean, >>> >>> >>> On 5/14/2012 2:45 PM, Jean Pihet wrote: >>>> >>>> Hi Benoit, >>>> >>>> On Fri, May 11, 2012 at 9:17 AM, Valentin, Eduardo >>>> <eduardo.valentin@xxxxxx> wrote: >>>>> >>>>> Hello Mark, >>>>> >>>>> On Wed, May 2, 2012 at 5:36 PM, mark gross<markgross@xxxxxxxxxxx> wrote: >>>>>> >>>>>> This is a Request For Participation in a micro-conference at this years >>>>>> Linux plumbers event. For this micro conference to happen we need to >>>>>> reach a certain critical mass WRT participants as measured by submitted >>>>>> talks associated to Power Management Constraints. >>>>> >>>>> >>>>> Nice! Thanks for proposing this. >>>>> >>>>>> >>>>>> The To: list is populated with folks that I've had interactions with >>>>>> over extending pm-qos or constraint based PM over the past year. >>>>>> >>>>>> If you are working on problems related to constraining the power / >>>>>> performance of devices I am inviting your participation and request you >>>>>> submit a proposal for presenting your problem space (preferred) and or >>>>>> solution to a group of developers looking for a good solution to push >>>>>> upstream. The talks will be about 20 min long as I want to get into >>>>>> some design and implementation discussions after the requirements >>>>>> definition is mostly finished. >>>> >>>> Is it OK to submit a talk for the next LPC? The deadline is tomorrow IIRC. >>> >>> >>> Yes, it is. Go ahead. It is related to Mark's proposal? Because it seems we >>> have to do some homework in order to participate to the micro-conf :-(. >> >> Yes, the homework is required in order to drive the discussion based >> on existing usable solutions.. >> >> Jean, I'll write down a proposal today, from thermal requirements >> perspective. But we can discuss also a way to converge either in a >> common presentation or in even with two presentations but with strong >> linking together. >> >> Just trying to avoid two conflicting proposals from two peers @ti.com >> >>> >>> Regards, >>> Benoit >>> >>> >>>> >>>> Regards, >>>> Jean >>>> >>>>>> >>>>>> I am interested in gathering user mode interface needs as well as kernel >>>>>> mode. >>>>>> >>>>>> From a high level pm-constraints is a generalization of pm-qos to >>>>>> include >>>>>> limiting performance as well as its current limiting of device >>>>>> throttling. >>>>>> >>>>>> As performance limiting is typically used for any of the following: >>>>>> 1) staying within thermal operational envelopes >>>>>> 2) avoiding peak current >>>>>> 3) extending battery life in active use cases >>>>>> >>>>>> I invite anyone working in any of these areas or pm-qos applications to >>>>>> participate in this micro-conference. >>>>>> >>>>>> I will organize the micro-conference into 2 parts: >>>>>> 1) problem statements with specific participant examples where >>>>>> constraining the performance or throttling is needed. >>>>> >>>>> >>>>> >>>>> I could bring something on the use cases where this type of >>>>> constraining could be used. Essentially major focus gets partitioned >>>>> in two areas: For device skin/case temperature management, and IC's >>>>> junction temperature management. >>>>> >>>>> I am currently checking the traveling arrangements as well. And >>>>> confirming soon. >>>>> >>>>> >>>>>> >>>>>> 2) high level design brain storming. >>>>>> >>>>>> If the micro-conference happens (i.e. critical mass is reached) any >>>>>> interested linux-plumbers attendees is very welcome to participate. >>>>>> >>>>>> Please send me an off list email if you want me to add you to my mutt >>>>>> alias of interested parties I'll use to cc people on emails. Note: must >>>>>> of the correspondence will cc linux-pm too. >>>>>> >>>>>> Please submit a proposal if you are interested in participating in this >>>>>> with me. I know a number of people are working in this space for the >>>>>> past few years now. I think its a good time to compare notes and at >>>>>> least consolidate requirements and use cases. Perhaps we'll even come >>>>>> up >>>>>> with a good design to implement in the process. >>>>>> >>>>>> thanks, >>>>>> --mark >>>>>> >>>>> >>>>> >>>>> All best, >>>>> -- >>>>> >>>>> Eduardo Valentin >>>>> _______________________________________________ >>>>> linux-pm mailing list >>>>> linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx >>>>> https://lists.linuxfoundation.org/mailman/listinfo/linux-pm >>> >>> >> >> >> >> -- >> >> Eduardo Valentin > > > > -- > > Eduardo Valentin _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/linux-pm
