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 build directory, generate the ddrinit-2133-xxxxxx.bin.out file after make
Follow the instruction as the below link to update the ddrinit
https://wiki.seeedstudio.com/BeagleV-Update-bootloader-ddr-init-boot-uboot-Recover-bootloader/