BBB Eeprom Restore

I’ve been experimenting with the BBB 32k eeprom. During this time I’ve fudged the eeprom up pretty good and got the system to a point where it doesn’t boot. I get:

Using: dtb=am335x-boneblack.dtb …
Checking if uname_r is set in /boot/uEnv.txt…
gpio: pin 56 (gpio 56) value is 1
Running uname_boot …
** Invalid partition 3 **
** Invalid partition 4 **
** Invalid partition 5 **
** Invalid partition 6 **
** Invalid partition 7 **

Error: “bootcmd_nand0” not defined


This same thing happened with “dtb”, where it suddenly became “undefined”. I placed a definition in the uEnv and that fixed it… but later, “bootcmd_nand0” became an issue. Anyone know how to define bootcmd_nand0? Or better yet, how can I restore the eeprom back to factory setting? Was it the eeprom that caused this issue in the first place? Since I was doing nothing else other than writing to eeprom, I wonder if that is what caused the issue. Are u-boot environment variables stored in eeprom? Did I muck them up? Note that booting from an SD card still generates this msg which leads me to believe it’s not flash, it’s e2.


Yes, there is (was) some important information in the EEPROM that the Linux kernel needs to boot.
The information basically tells the kernel that it is dealing with a BBB, so that it knows how to configure
the board (I/O, power supplies, and stuff like that.)

You might try searching for and reading past reflector topics like:

BBB EEPROM details 1/21/15

EEPROM contents 5/13/15

Cloning Beaglebone 7/29/15

— Graham