* (C) Copyright 2001
* Dave Ellis, SIXNET, dge@sixnetio.com
*
- * See file CREDITS for list of people who contributed to this
- * project.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
+ * SPDX-License-Identifier: GPL-2.0+
*/
Using autoboot configuration options
CONFIG_BOOT_RETRY_TIME
CONFIG_BOOT_RETRY_MIN
- bootretry environment variable
+ "bootretry" environment variable
- These options determine what happens after autoboot is
- stopped and U-Boot is waiting for commands.
+ These options determine what happens after autoboot is
+ stopped and U-Boot is waiting for commands.
- CONFIG_BOOT_RETRY_TIME must be defined to enable the boot
- retry feature. If the environment variable 'bootretry' is
- found then its value is used, otherwise the retry timeout is
- CONFIG_BOOT_RETRY_TIME. CONFIG_BOOT_RETRY_MIN is optional and
- defaults to CONFIG_BOOT_RETRY_TIME. All times are in seconds.
+ CONFIG_BOOT_RETRY_TIME must be defined to enable the boot
+ retry feature. If the environment variable "bootretry" is
+ found then its value is used, otherwise the retry timeout is
+ CONFIG_BOOT_RETRY_TIME. CONFIG_BOOT_RETRY_MIN is optional and
+ defaults to CONFIG_BOOT_RETRY_TIME. All times are in seconds.
- If the retry timeout is negative, the U-Boot command prompt
- never times out. Otherwise it is forced to be at least
- CONFIG_BOOT_RETRY_MIN seconds. If no valid U-Boot command is
- entered before the specified time the boot delay sequence is
- restarted. Each command that U-Boot executes restarts the
- timeout.
+ If the retry timeout is negative, the U-Boot command prompt
+ never times out. Otherwise it is forced to be at least
+ CONFIG_BOOT_RETRY_MIN seconds. If no valid U-Boot command is
+ entered before the specified time the boot delay sequence is
+ restarted. Each command that U-Boot executes restarts the
+ timeout.
- If CONFIG_BOOT_RETRY_TIME < 0 the feature is there, but
- doesn't do anything unless the environment variable
- 'bootretry' is >= 0.
+ If CONFIG_BOOT_RETRY_TIME < 0 the feature is there, but
+ doesn't do anything unless the environment variable
+ "bootretry" is >= 0.
CONFIG_AUTOBOOT_KEYED
+ CONFIG_AUTOBOOT_KEYED_CTRLC
CONFIG_AUTOBOOT_PROMPT
CONFIG_AUTOBOOT_DELAY_STR
CONFIG_AUTOBOOT_STOP_STR
CONFIG_AUTOBOOT_DELAY_STR2
CONFIG_AUTOBOOT_STOP_STR2
- bootdelaykey environment variable
- bootstopkey environment variable
- bootdelaykey2 environment variable
- bootstopkey2 environment variable
+ "bootdelaykey" environment variable
+ "bootstopkey" environment variable
+ "bootdelaykey2" environment variable
+ "bootstopkey2" environment variable
- These options give more control over stopping autoboot. When
- they are used a specific character or string is required to
- stop or delay autoboot.
+ These options give more control over stopping autoboot. When
+ they are used a specific character or string is required to
+ stop or delay autoboot.
Define CONFIG_AUTOBOOT_KEYED (no value required) to enable
- this group of options. CONFIG_AUTOBOOT_DELAY_STR,
+ this group of options. CONFIG_AUTOBOOT_DELAY_STR,
CONFIG_AUTOBOOT_STOP_STR or both should be specified (or
specified by the corresponding environment variable),
otherwise there is no way to stop autoboot.
- CONFIG_AUTOBOOT_PROMPT is displayed before the boot delay
- selected by CONFIG_BOOTDELAY starts. If it is not defined
- there is no output indicating that autoboot is in progress.
- If "%d" is included, it is replaced by the number of seconds
- remaining before autoboot will start, but it does not count
- down the seconds. "autoboot in %d seconds\n" is a reasonable
- prompt.
-
- If CONFIG_AUTOBOOT_DELAY_STR or bootdelaykey is specified and
- this string is received from console input before autoboot
- starts booting, U-Boot gives a command prompt. The U-Boot
- prompt will time out if CONFIG_BOOT_RETRY_TIME is used,
- otherwise it never times out.
-
- If CONFIG_AUTOBOOT_STOP_STR or bootstopkey is specified and
- this string is received from console input before autoboot
- starts booting, U-Boot gives a command prompt. The U-Boot
- prompt never times out, even if CONFIG_BOOT_RETRY_TIME is
- used.
-
- The string recognition is not very sophisticated. If a
- partial match is detected, the first non-matching character
- is checked to see if starts a new match. There is no check
- for a shorter partial match, so it's best if the first
- character of a key string does not appear in the rest of the
- string.
-
- Using the CONFIG_AUTOBOOT_DELAY_STR2 / bootdelaykey2 and/or
- CONFIG_AUTOBOOT_STOP_STR2 / bootstopkey #defines and/or
- environment variables you can specify a second, alternate
- string (which allows you to haw two "password" strings).
+ CONFIG_AUTOBOOT_PROMPT is displayed before the boot delay
+ selected by CONFIG_BOOTDELAY starts. If it is not defined
+ there is no output indicating that autoboot is in progress.
+
+ Note that CONFIG_AUTOBOOT_PROMPT is used as the (only)
+ argument to a printf() call, so it may contain '%' format
+ specifications, provided that it also includes, sepearated by
+ commas exactly like in a printf statement, the required
+ arguments. It is the responsibility of the user to select only
+ such arguments that are valid in the given context. A
+ reasonable prompt could be defined as
+
+ #define CONFIG_AUTOBOOT_PROMPT \
+ "autoboot in %d seconds\n",bootdelay
+
+ If CONFIG_AUTOBOOT_DELAY_STR or "bootdelaykey" is specified
+ and this string is received from console input before
+ autoboot starts booting, U-Boot gives a command prompt. The
+ U-Boot prompt will time out if CONFIG_BOOT_RETRY_TIME is
+ used, otherwise it never times out.
+
+ If CONFIG_AUTOBOOT_STOP_STR or "bootstopkey" is specified and
+ this string is received from console input before autoboot
+ starts booting, U-Boot gives a command prompt. The U-Boot
+ prompt never times out, even if CONFIG_BOOT_RETRY_TIME is
+ used.
+
+ The string recognition is not very sophisticated. If a
+ partial match is detected, the first non-matching character
+ is checked to see if starts a new match. There is no check
+ for a shorter partial match, so it's best if the first
+ character of a key string does not appear in the rest of the
+ string.
+
+ Using the CONFIG_AUTOBOOT_DELAY_STR2 #define or the
+ "bootdelaykey2" environment variable and/or the
+ CONFIG_AUTOBOOT_STOP_STR2 #define or the "bootstopkey"
+ environment variable you can specify a second, alternate
+ string (which allows you to have two "password" strings).
+
+ The CONFIG_AUTOBOOT_KEYED_CTRLC #define allows for the boot
+ sequence to be interrupted by ctrl-c, in addition to the
+ "bootdelaykey" and "bootstopkey". Setting this variable
+ provides an escape sequence from the limited "password"
+ strings.
+
CONFIG_ZERO_BOOTDELAY_CHECK
- 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.
+ 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.
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.
-
+ (Only effective when CONFIG_BOOT_RETRY_TIME is also set)
+ After the countdown timed out, the board will be reset to restart
+ again.
projects / karo-tx-uboot.git / blobdiff