0. download an generic arm architecture toolchains

1. build kernel

cd kernel path

cd kernel

generate configs

cp arch/arm/configs/realtek/config.develop.android.r.rtd288o.tv030.emmc.andtv.optee.old_defconfig .config make menuconfig

compile with prebuilts toolchains

make -jN ARCH=arm CROSS_COMPILE=${CROSS_COMPILE}

2. build wifi driver mt76x8

cd driver path

cd vendor/gen4m

compile with prebuilts toolchains, output name: wlan_mt76x8_usb.ko

make -jN -f Makefile.ce TYPE=rt2851m_trom CHIP=mt76x8 LINUX_SRC=../../kernel CROSS_COMPILE=${CROSS_COMPILE}