Manually Flashing Firmware

DANGER

Flashing your own firmware has the potential to brick your device. Do not do this unless you are sure you know what you're doing and have a way to recover from a bad flash. Some level of knowledge with using the Linux command line is required.

The steps below assume you are flashing an image named coreboot.rom; substitute it as necessary.

1. Download flashrom, cbfstool, and gbb utility, decompress, and ensure they are executable:

   • wget -O flashrom.tar.gz https://mrchromebox.tech/files/util/flashrom_ups_libpci37_20240418.tar.gz && tar -zxf flashrom.tar.gz && chmod +x flashrom
   • wget https://mrchromebox.tech/files/util/cbfstool.tar.gz && tar -zxf cbfstool.tar.gz && chmod +x cbfstool
   • wget https://mrchromebox.tech/files/util/gbb_utility.tar.gz && tar -zxf gbb_utility.tar.gz && chmod +x gbb_utility

2. Flash your custom ROM

   • Backup your current firmware (just in case things go wrong): sudo ./flashrom -p internal -r backup.rom
   • Extract your VPD from your backup: ./cbfstool backup.rom read -r RO_VPD -f vpd.bin
   • Inject the VPD into your custom ROM: ./cbfstool coreboot.rom write -r RO_VPD -f vpd.bin
   • Extract your HWID and inject it into the custom ROM (if it exists)
     • if your current firmware came from the firmware utility script run
       • ./cbfstool backup.rom extract -n hwid -f hwid.txt
     • if it is stock firmware then run
       • ./gbb_utility backup.rom --get --hwid > hwid.txt
     • ./cbfstool coreboot.rom add -n hwid -f hwid.txt -t raw
   • Flash your custom firmware:
     • AMD devices: sudo ./flashrom -p internal -w coreboot.rom
     • Intel devices: sudo ./flashrom -p internal --ifd -i bios -w coreboot.rom

3. Reboot

   • Assuming flashrom shows success at the end of the process, reboot.