NAME

       u-boot-update - program to generate u-boot menu files

SYNOPSIS

       u-boot-update

DESCRIPTION

       u-boot-update  is  a  tool  used to generate the menu files used by the U-BOOT bootloader.
       Options can be configured in /etc/default/u-boot.

OPTIONS

       U_BOOT_UPDATE="true|false"
           This variable specifies if u-boot-update is allowed to modify the configuration  files
           in /boot/extlinux. Values are either 'true' or 'false', default is 'true'.

       U_BOOT_ALTERNATIVES="default recovery"
           This  variable  specifies  which  entries  u-boot-update  is  populating.  Values  are
           'default', 'recovery', 'live', default is 'default recovery'.

       U_BOOT_DEFAULT="l0"
           This variable specifies the default entry to boot. The name of an  entry  consists  of
           two or three characters. Linux kernel images start with the letter 'l', followed by an
           integer started by '0' for the first kernel version (which is numerically the  highest
           one  in  case  kernel  images  of  more  than  one  linux  version are installed) and,
           optionally, the mode (r for rescue mode, l for live mode). Memdisk entries start  with
           the  letter  'm',  followed by an integer, no optional modes available. The default is
           'l0'.

       U_BOOT_ENTRIES="all"
           This variables specifies how many kernel versions should be used to populate the  boot
           configuration.  Value  is  an  integer  starting  with 1, or 'all' to populate for all
           kernels, default is 'all'.

       U_BOOT_MENU_LABEL="Debian GNU/Linux, kernel"
           This variable specifies the text that is used as a description in the boot menu. Value
           is  an  arbitrary  string. If not specified, PRETTY_NAME from /etc/os-release is used.
           Otherwise, it defaults to 'Debian GNU/Linux, kernel'.

       U_BOOT_PARAMETERS="ro quiet"
           This variable specifies additional boot parameters that are appended  to  each  kernel
           entry.  Value  is  an  arbitrary  string,  default  is 'ro quiet' (except for recovery
           entries, where quiet is avoided).

       U_BOOT_ROOT="root=DEVICE"
           This variable specifies  the  root  partition.  It  is  automatically  extracted  from
           /etc/fstab. U-BOOT supports both devices and UUIDs.

       U_BOOT_TIMEOUT="50"
           This  variable  specifies the time that U-BOOT should wait for user input during boot.
           Values are in decisecond greater than  0  (e.g.  '10'  for  a  1  second  timeout),  0
           specifies to wait forever. The default is 50.

FILES

       /etc/default/u-boot

HOMEPAGE

       More information about U-BOOT can be found at <http://www.denx.de/wiki/U-Boot>.

       u-boot-update and this manual page was written by Daniel Baumann <daniel.baumann@progress-
       technologies.net> for extlinux. Riku Voipio <riku.voipio@linaro.org> updated them  for  u-
       boot.