Hi Shawn, Am Dienstag, den 03.07.2018, 15:12 +0800 schrieb Shawn Guo: > On Mon, May 28, 2018 at 04:37:39PM +0530, Viresh Kumar wrote: > > Hi Lucas, > > > > On 25-05-18, 13:46, Lucas Stach wrote: > > > This is a lot of duplicate information for what is effectively a shared > > > cluster wide thing. This does absolutely not _feel_ right. > > > > I cannot agree more :) > > > > > What problem are you solving here? Why do we need all this duplicate > > > information? Why can't we fix it by falling back to looking at cpu0 if > > > needed? > > > > Let me try explaining one of the problem scenarios to you as your > > platform is a single cluster one. Make cpufreq driver as module, don't > > insert it, hotplug out CPU0 and now insert the cpufreq driver. The > > cpufreq core will try adding the cpufreq policy for CPU1 but wouldn't > > find the required information in the DT node of CPU1 and so will fail > > or behave incorrectly. > > > > We can't look at CPU0 as we don't know they are related at all. > > Nothing tells that to us. The right solution to fix the duplication is > > to move to OPP-v2 bindings, which allow us to create a single OPP > > table node and refer to it from all the CPU nodes. Because in case of > > imx platforms getting updated here, we use the old and some platforms > > specific frequency tables, we have to duplicate it everywhere. > > > > But looking from DT otherwise, all the device should anyway have all > > the information required right in their node. That can be simplified > > with things like phandle to opp-v2 node, but still everything needs to > > be there. We shouldn't really rely on other CPU nodes to make it work. > > That would be an incomplete definition of the hardware IMHO. > > Lucas, > > Are you fine with the patch now considering the respond from Viresh? I still don't like the huge duplication of information in the DT, but I agree that it's currently necessary for correctness. Long term I hope we can get away from cpufreq-imx6 and the custom SoC OPPs, which would allow us to switch over to OPPv2. So patch is: Reluctantly-acked-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx> Regards, Lucas -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
