Does the mt7688 have linux kernel support for frequency scaling? I was able to build a 4.14.63 kernel for the Linkit Smart 7688. In the kernel build I enabled CONFIG_PM_DEVFREQ and all the frequency governors (such as CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND). The resulting kernel booted, but there is no cpufreq directory under "/sys/devices/system/cpu/cpu0".
A related question is in regards to the spec sheet feature "intelligent clock scaling". How can this feature be controlled from user space?