hum...i'm sort of in two minds about this. digging further through the existing patch series on master, it seems that a lot of this stuff is meant to be handled by that patch series. in particular, it looks like the pull-down to the idle clock for L2 prior to setting the intended frequency ought to be handled, at least at first glance.
as far as the L2 frequencies go, it has no support for defining the required voltages for the L2 cache, nor does it take it account the different scaling of the L2 compared with the cpu frequency, it assumes that the L2 will just run at the same frequency as the CPU, which contradicts https://source.codeaurora.org/quic/qsdk/oss/kernel/linux-msm/tree/arch/arm/boot/dts/qcom-ipq8064.dtsi?h=NHSS.QSDK.10.0
so on the one hand i could try and work out why the existing patch series doesn't work and perhaps find a smaller fix. or i could persist with deleting it and replacing it with something that i know works. the existing patch series is from 2015 and has never been merged upstream as far as i can tell, though i think some variant of it resurfaced this month.