hello, On Thu, May 31, 2012 at 11:32:41AM +0800, Zhang Rui wrote: > On 三, 2012-05-30 at 14:17 +0300, Eduardo Valentin wrote: > > Hello Durga, > > > > On Wed, May 30, 2012 at 11:05:18AM +0000, R, Durgadoss wrote: > > > Hi Eduardo, > > > > > > > > > > > For G1+G2, I agree with your proposal. I had some discussion with Amit > > > > regarding this. In his series of patches we increase / decrease the cooling > > > > device state linearly and steadily. > > > > > > > > But if we would have what you are saying, we could bind cooling device > > > > set of states with trip points. > > > > > > True, We want to bind the levels of cooling with the trips points a thermal zone has. > > > But we might not get a 1-1 mapping always. > > > > Just to make sure we are all taking the same thing. > > > > In this case a cooling device would have 1-N states. And this set could > > be partitioned and each partition would be assigned to a specific trip point > > of a thermal zone, right? > > > yep. > BTW, Overlaps should be possible and we should handle this as well. > > > > > > > > > > > > > > > I fully support this option and could cook up something on this. > > > > The TC1 and TC2 should go inside the .get_trend() callbacks for ACPI. > > > > Should probably go away from the registration function that we have > > > > currently. > > > > > > I realize I just said the same thing :-) > > > > Cool :-) > > > > > > > > > > > > > We could have generic trending computation though. Based on timestamping > > > > and temperature reads, and make it available for zones that want to used it. > > > > > > Agree, but I would like this go into the platform thermal drivers. And then when > > > those drivers notify the framework they can specify the trend also. This sort of > > > notification is not there, but that is what I am implementing these days.. > > > Hope to submit this patch in a week's time.. > > > > Nice, I actually have something being cooked for the same thing. We should probably > > align to avoid work duplication... > > > Hah, seems a lot of work is in progress in this area. > > > > > > > > > > case THERMAL_TRIP_ACTIVE: > > > > > > case THERMAL_TRIP_PASSIVE: > > > > > > ... > > > > > > tz->ops->get_trend(); > > > > > > > > Would the get_trend take into account if we are cooling with active or passive > > > > cooling device? > > > > > > To me, it does not matter. It is up to the framework to decide and throttle, > > > the respective cooling devices according to the trend. > > > > OK. For me it doesn't really matter as well. Having a simplified zone update is better. > > > > > > > > > > > > > > > if (trend == HEATING) > > > > > > cdev->ops->set_cur_state(cdev, cur_state++); > > > > > > else if (trend == COOLING) > > > > > > cdev->ops->set_cur_state(cdev, cur_state--); > > > > > > break; > > > > > > > > I believe we should have something for temperature stabilization there as well. > > > > > > > > Besides, if we go with this generic policy, then the zone update would be much > > > > simpler no? > > > > > > Yes, and that’s what we want too :-) > > > > Nice! > > > > > > > > > Here are some other thoughts: > > > > G6. Another point is, would it make sense to allow for policy extension? Meaning, > > > > the zone update would call a callback to request for update from the zone > > > > device driver? > > > > > > > > G7. How do we solve cooling devices being shared between different thermal > > > > zones? > > > > Should we have a better cooling device constraint management? > > > > > > This is another thing that was haunting me for quite some time. > > > And What I have in mind is a mapping kind of thing in the platform layer, > > > that will provide details about which cooling device is shared with whom. > > > The framework can then use this and figure out the association among various devices. > > > I am testing it out, and will submit once it comes to a good shape. > > > > Right, I am not sure we want to go in this direction? > > > > Maybe a better way would be to have sort of pm/thermal contraint framework, which > > would map these per device, at LDM level? > > > > I am copying Jean-Pihet, he has been working in this front. Jean, any thoughts? > > > Durga and I are investigating how to introduce some concepts like > "influence/weight" to generic thermal layer. :) What do you mean here? Describing the cooling devices effectiveness on each zone and derive algorithms to act accordingly? > > thanks, > rui > _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/linux-pm
