What did I do wrong for kernel upgrade?

[honanduc]

Hello. What I tried was native compile on the odroid n2+ I wish to install kernel 5.15 on:

git clone --depth 1 https://github.com/tobetter/linux -b odroid-5.15.y
cd linux
make defconfig
# I didn't edit config file or make menuconfig
make -j4
sudo make modules_install
sudo cp -f arch/arm64/boot/Image.gz arch/arm64/boot/dts/amlogic/meson64_odroidn2.dtb /media/boot/
sudo sync
sudo reboot

It was built without errors. After the reboot the screen was just black. The red LED and blue LED on the odroid were on solid color, no blinking blue heart beat. What did I miss? It's my first time doing this.

Thank you in advance.