I downloaded buildroot package and tried to build using a config file under /configs directory such as raspberrypi3_64_defconfig.
If I run make menuconfig, menuconfig screen loads a default config. If I copy the raspberrypi3_64_defconfig under /buildroot and change the name to .config and run make menuconfig, then I can see the configs for raspberrypi3_64.
Is there any way I can specify the raspberrypi3_64_defconfig when I run make menuconfig without copying the file and renaming it?