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-rw-r--r--doc/README.autoboot121
1 files changed, 60 insertions, 61 deletions
diff --git a/doc/README.autoboot b/doc/README.autoboot
index 20736ca476..a6d5f992da 100644
--- a/doc/README.autoboot
+++ b/doc/README.autoboot
@@ -69,25 +69,25 @@ What they do
bootretry environment variable
- 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.
-
- 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.
+ 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.
+
+ 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.
CONFIG_AUTOBOOT_KEYED
CONFIG_AUTOBOOT_PROMPT
@@ -101,9 +101,9 @@ What they do
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,
@@ -111,48 +111,47 @@ What they do
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.
+ 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_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.