- If this option is defined, you can stop the autoboot process
- by hitting a key even in that case when "bootdelay" has been
- set to 0. You can set "bootdelay" to a negative value to
- prevent the check for console input.
+ "bootstopkeysha256" environment variable
+
+ - Hash value of the input which unlocks the device and
+ stops autoboot.
+
+ This option allows a string to be entered into U-Boot to stop the
+ autoboot. The string itself is hashed and compared against the hash
+ in the environment variable 'bootstopkeysha256'. If it matches then
+ boot stops and a command-line prompt is presented.
+
+ This provides a way to ship a secure production device which can also
+ be accessed at the U-Boot command line.