Ahh ok,
Thank you. It seems that the voltage regulator on the zero is supported (its just GPIO) and it has the same regulator as one the orangepi-one. So it should just be a matter of adapting that from the orangepi-one dts and to add DVFS and higher speed to the zero as well.
It's a bit odd that this has not been done but it seems to be implemented on later kernel version.
Thank for your answer!
regards,