Thank you @numbqq and @Frank.
I will figure out how to setup cross compiler correctly and share it.
On the other hand fenix is really a good choice to make life easier.
So I am trying to use it to build dtb files and use updated dtb files to update my bootimage of vim3 android pie AOSP.
Currently there are two topics in my mind wanted to be clarified :]
I posted it as a reply on VIM3 GPIO’s, SPI, UART, with Android 9 Pie.
Thanks to have your dedicated support.