So actually after I downloaded the android 10.0.0 BSP, I saw they had instructions on building the uboot using their imx-make.sh script. I am able to build the uboot code using that script, but I haven't yet figured out how does the imx-make script setup the .config file for uboot compile. If I go to android_build/vendor/nxp-opensource/uboot/, I would need to setup the .config by running make menuconfig, before I can run make for uboot. How does regular android build system setup the .config files for uboot ?
thanks