+SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2001
* Dave Ellis, SIXNET, dge@sixnetio.com
*
- * SPDX-License-Identifier: GPL-2.0+
*/
Using autoboot configuration options
provides an escape sequence from the limited "password"
strings.
+ CONFIG_AUTOBOOT_ENCRYPTION
- CONFIG_ZERO_BOOTDELAY_CHECK
+ "bootstopkeysha256" environment variable
- 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.
+ - 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.
CONFIG_RESET_TO_RETRY
(Only effective when CONFIG_BOOT_RETRY_TIME is also set)
After the countdown timed out, the board will be reset to restart
again.
+
+ CONFIG_AUTOBOOT_USE_MENUKEY
+ CONFIG_AUTOBOOT_MENUKEY
+
+ If this key is pressed to stop autoboot, then the commands in the
+ environment variable 'menucmd' will be executed before boot starts.
+ For example, 33 means "!" in ASCII, so pressing ! at boot would take
+ this action.