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Except that the >>> bpmp on those archs does not support bandwidth manager, so the scaling >>> iteself is handled similar to how Tegra124 currently works. >>> >>> Signed-off-by: Aaron Kling >>> --- >> Tegra186/194 had multiple drivers for BWMGR, ISOMGR and LA+PTSA configs >> on the CPU side. I am not sure how effective this patch series will be >> in absence >> of those components. In Tegra234, those were moved to BPMP-FW. So, Kernel >> forwards the BW request to BPMP (R5) who takes care of setting the final >> freq. > I know it's not ideal, but it seems to be working okay as a rough > approximation. When the cpu governor kicks up the cpu freq, the emc > freq scales to match. In my testing, this has been enough to keep aosp > from obviously lagging. Existing drivers for earlier archs, such as > tegra124-emc, stub out LA+PTSA as well. Does the lack of that handling > make things worse for Tegra186/194 than it would for > Tegra124/Tegra210? I'm trying to improve things across all these archs > small pieces at time. In several of my recent series, I'm just trying > to get any form of load based dfs to work, so I don't have to keep > everything pegged to max frequency with the associated thermals and > power usage. > > Aaron I am not much familiar with the previous SoCs. But yes having some kind of scaling is better than not having at all and running always at max. This can be a starting point of more improvements for these SoCs in future. Thank you, Sumit Gupta