Linux or Mac
Download links: https://mirrors.lolinet.com/firmware/gsi/
XDA thread: https://forum.xda-developers.com/project-treble/trebleenabled-device-development/pie-erfan-gsi-ports-t3906486
Telegram group: https://t.me/ErfanGSIs
Telegram channel: https://t.me/ErfanGSI
git clone --recurse-submodules https://github.com/mi20210630/ErfanGSIs.git
cd ErfanGSIs
bash setup.sh
Example: for making OxygenOS of oneplus 7 pro firmware, you can use this command
./url2GSI.sh https://oxygenos.oneplus.net/OnePlus7ProOxygen_21.O.07_OTA_007_all_1905120542_fc480574576b4843.zip OxygenOS
check url2GSI.sh for more info