NAME

mkubootimage — create U-Boot loader image

SYNOPSIS

DESCRIPTION

The mkubootimage utility is used to create an image for Das U-Boot, the "Universal Boot Loader".

The arguments are as follows:

-A (arm|arm64|i386|mips|mips64|or1k|powerpc|riscv|sh): Defines the architecture. This is required for ‘uimg’ format images.
-a address: Sets the image load address. This is an integer between 0 and UINT32_MAX. This is required for all ‘uimg’ image types except for script, ramdisk, and kernel_noload.
-C (bz2|gz|lzma|lzo|none): Defines the compression. The default is ‘none’.
-E address: Define the entry point. This is an integer between 0 and UINT32_MAX. This option is the same as -e but it inverts the bytes to convert the 32 bit integer from little to big endian (or vice versa). If -E or -e are not set, the entry point defaults to the image load address (-a).
-e address: Define the entry point. This is an integer between 0 and UINT32_MAX. If -E or -e are not set, the entry point defaults to the image load address (-a).
-f (arm64|uimg): Defines the output image format type. The default is ‘uimg’.
-h: Display the usage and exit.
-m magic: Set the magic used for ‘uimg’ format images. This is an integer between 0 and UINT32_MAX. The default is ‘0x27051956’.
-n name: Defines the image name. This is required.
-O (freebsd|linux|netbsd|openbsd): Defines the operating system type. The default OS name is ‘netbsd’.
-T (fs|kernel|kernel_noload|ramdisk|script|standalone): Defines the image type. This is required for ‘uimg’ format images.
-t epoch: Use given epoch timestamp as image creation time. (This is only used for legacy U-Boot images.)
-u: Update the header in an existing file instead of creating a new one.

The required source argument is the filename of the kernel that is read. The required destination argument is the filename of the image file that is created.

EXIT STATUS

mkubootimage returns 1 on failure to read the kernel, generate a header, or create the image.

EXAMPLES

Before the image is written, the header is displayed to standard out; for example:

 image type:  uimg
 magic:       0x27051956
 time:        Tue May 21 18:05:09 2024
 size:        137
 load addr:   0x00000000
 entry point: 0x00000000
 data crc:    0xface05f2
 os:          2 (netbsd)
 arch:        2 (arm)
 type:        6 (script)
 comp:        0 (none)
 name:        NetBSD/armv7 boot
 header crc:  0x2164b567

HISTORY

The mkubootimage command first appeared in NetBSD 6.0.

AUTHORS

The mkubootimage utility was originally written by Jared McNeill. This manual page was written by Jeremy C. Reed.