X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=doc%2FREADME.autoboot;h=2042fe5c4063b95e791cbbd29744f85665782e10;hb=6b8be3e58e9cc1badb7a709b0f3568d4d8eca4b7;hp=a6d5f992da0aec53daa97f1cebaa85ecfbe794c8;hpb=8bde7f776c77b343aca29b8c7b58464d915ac245;p=oweals%2Fu-boot.git diff --git a/doc/README.autoboot b/doc/README.autoboot index a6d5f992da..2042fe5c40 100644 --- a/doc/README.autoboot +++ b/doc/README.autoboot @@ -12,7 +12,7 @@ * * 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 + * 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 @@ -67,13 +67,13 @@ What they do 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. CONFIG_BOOT_RETRY_TIME must be defined to enable the boot - retry feature. If the environment variable 'bootretry' is + 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. @@ -87,7 +87,7 @@ What they do If CONFIG_BOOT_RETRY_TIME < 0 the feature is there, but doesn't do anything unless the environment variable - 'bootretry' is >= 0. + "bootretry" is >= 0. CONFIG_AUTOBOOT_KEYED CONFIG_AUTOBOOT_PROMPT @@ -96,17 +96,17 @@ What they do 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. 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. @@ -114,18 +114,25 @@ What they do 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. + 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 + 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 @@ -138,10 +145,11 @@ What they do 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). + 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). CONFIG_ZERO_BOOTDELAY_CHECK