mkubootimage —
create U-Boot loader image
  
    | mkubootimage | [ -hu]-A(arm|arm64|i386|mips|mips64|or1k|powerpc|sh)-aaddress
      [-C(bz2|gz|lzma|lzo|none)]
      [-Eaddress]
      [-eaddress]
      [-f(arm64|uimg)] [-mmagic]-nimage [-O(freebsd|linux|netbsd|openbsd)]-T(fs|kernel|kernel_noload|ramdisk|script|standalone)
      source destination | 
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|sh)
- Defines the architecture. This is required for “uimg” format
      images.
- -aaddress
- 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”.
- -Eaddress
- Define the entry point. This is an integer between 0 and
      UINT32_MAX. This option is the same as-ebut it inverts the bytes to convert the 32 bit
      integer from little to big endian (or vice versa). If-Eor-eare not set, the
      entry point defaults to the image load address
      (-a).
- -eaddress
- Define the entry point. This is an integer between 0 and
      UINT32_MAX. If-Eor-eare 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.
- -mmagic
- Set the magic used for “uimg” format images. This is an
      integer between 0 and UINT32_MAX. The default is
      “0x27051956”.
- -nimage
- Defines the image name. This is required.
- -O(freebsd|linux|netbsd|openbsd)
- Defines the operating system type. The default OS name is
      “netbsd”.
- -tepoch
- Use given epoch timestamp as image creation time. (This is only used for
      legacy U-Boot images.)
- -T(fs|kernel|kernel_noload|ramdisk|script|standalone)
- Defines the image type. This is required for “uimg” format
      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.
mkubootimage returns 1 on failure to read the kernel,
  generate a header, or create the image.
Before the image is written, the header is displayed to standard out; for
  example:
 magic:       0x27051956
 time:        Tue Jun  7 15:58:41 2011
 size:        2482203
 load addr:   0x00020000
 entry point: 0x00020000
 data crc:    0x700fdf53
 os:          2 (netbsd)
 arch:        7 (powerpc)
 type:        2 (kernel)
 comp:        1 (gz)
 name:        NetBSD/evbppc 5.99.52 (INSTALL_PMPPC)
 header crc:  0x94ea96cf
 
“Das U-Boot - the Universal Boot Loader”
  http://www.denx.de/wiki/U-Boot/
The mkubootimage command first appeared in
  NetBSD 6.0.
The mkubootimage utility was originally written by
  Jared McNeill. This manual page was written by
  Jeremy C. Reed.