Compute Module • Re: CM4 EEPROM confusion

- The CM4 doesn't allow EEPROM updates through a reboot like the Pi4. This is as far as I now a limitation as the low-level ROM Loader can't read the update file from eMMC, but it can read it from SD-Card?

its more of a config and safety issue

the problem is that recovery.bin on the sd/emmc has the highest priority for booting
so if there is a recovery.bin on the emmc, then you may wind with a bricked CM4, because you cant boot anything else to be able to access the emmc and remove it

to prevent this bricking issue, loading recovery.bin from emmc was disabled via OTP/fuses

What is the reason why this method is not "recommended"?

again, bricking reasons
if you use flashrom within linux to update the eeprom, and power is interrupted mid-flash, then it will be soft-bricked
and only using rpiboot can you unbrick things

the intent, is that you basically always use rpiboot to update the eeprom

Statistics: Posted by cleverca22 — Wed Dec 10, 2025 1:36 am

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