Download compiler according to your enviroment as the below link:
https://github.com/sifive/freedom-tools/releases/tag/v2020.12.0
Add the compiler to your PATH:
export PATH=/home/user/compiler/bin:$PATH
Enter the project directory, generate the jh7100_recovery_boot.bin file in debug directory after make
Follow the recovery tools and instruction as the below link to recover the bootloader https://github.com/kprasadvnsi/JH71xx-tools