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If such a situation >>>> occurs, it will be very difficult to troubleshoot. How should this >>>> situation be handled more reasonably? >>> Fix your consumers drivers if you need to. Set range if you must. I don't think it's reliable to have consumers drivers self-regulate. They are very likely to overlook this constraint. Moreover, when the clock configuration exceeds the constraint, if their own module can handle it but it affects other modules, this situation can easily mislead people to look for the problem in the wrong direction. Setting the range offers relatively higher fault tolerance, but it requires adding members to each "clk_regmap_**_data" and implementing callback functions *init() in the ops of each type of clock (*init() calls clk_hw_set_rate_range to set the range of the provider). This seems to complicate the originally simple logic. >>> Those are not clock provider constraints. Those are use-case ones. It >>> does belong here and CCF already provides the necessary infra to deal >>> with ranges. >> I kind of disagree here, if the vendor has the data and is willing to share >> the range for each clock path of the system, I think it should be welcome! >> >> Usually those ranges are not disclosed, so we don't set them, but CCF will >> certainly use all those range to make an even better decision on the lock >> routing. > I did not say you should not use them, I say that a platform > use-case, which is what this is, should not be hard coded within the > clock provider driver. > > This is no different than an assigned-rate, and like any other platform > description, it belong in DT. > > We've already seen how these ranges may depend on what else you choose > to do on the system or even what package a particular SoC variant is > using. That makes sense. The information I have doesn't make a distinction, I'm not sure if other manufacturers do. I think it's more controllable to converge this clock constraint issue within our clock driver. Should we implement this constraint in Amlogic's clock driver? > >> Neil >>