FAQ

⇒ After being plugged in the sd card must be initialised prior to any access. The command

mmc rescan 1

does that.

U-Boot prints the following error message at boot time:

setenv - set environment variables

Usage:
setenv name value ...
    - set environment variable 'name' to 'value ...'
setenv name
    - delete environment variable 'name'

⇒ Amongst others a reason for this is that the U-Boot environment variable bootargs has been accidentally stored in the flash environment and already contains a value. The error occurs because the final value (string) to be stored in this variable eventually becomes too long.

To remedy just clear the variable bootargs und save the environment to flash:

setenv bootargs
saveenv