Zynq mkbootimage

Copyright (c) 2015-2021 Antmicro

This is an open-source replacement for the Xilinx bootgen application. The package provides sources of two binaries mkbootimage and exbootimage for both creation and extraction of Zynq boot images.

The tools are written entirely in C.

Requires the libelf C library.

To build these the tools run:

make

For details on project organization and contribution tips, see src/README.md.

mkbootimage

mkbootimage parses a .bif file and creates a Zynq boot image in the .bin format.

To use it, type in:

./mkbootimage [--parse-only|-p] [--zynqmp|-u] <input_bif_file> <output_bin_file>

To see all available options, run:

./mkbootimage --help

Zynq-7000

For Zynq-7000 series, zynq-mkbootimage currently supports creating boot images containing the FSBL, bitstream, U-Boot, and Linux-related binary files.

For loading Linux-related images, both the [load] and the [offset] attributes are supported. As opposed to the original bootgen utility, file extensions are not required.

For example the following .bif file:

the_ROM_image:
{
  [bootloader]fsbl.elf
  fpga.bit
  u-boot.elf
  [load=0x2a00000]devicetree.dtb
  [load=0x2000000]uramdisk
  [load=0x3000000]uImage
}

used with the following command:

./mkbootimage boot.bif boot.bin

will generate a .bin image which can be used in U-Boot, as follows:

bootm 0x3000000 0x2000000 0x2a00000

Zynq UltraScale+

For Zynq UltraScale+, zynq-mkbootimage currently supports creating boot images containing the FSBL, bitstream, U-Boot, ARM trusted software and Linux-related binary images.

For example the following .bif file:

the_ROM_image:
{
  [fsbl_config] a53_x64
  [bootloader] fsbl.elf
  [destination_device=pl] fpga.bit
  [, destination_cpu=a53-0, exception_level=el-2] bl31.elf
  [, destination_cpu=a53-0, exception_level=el-2] u-boot.elf
  [load=0x2a00000]devicetree.dtb
  [load=0x2000000]uramdisk
  [load=0x3000000]uImage
}

used with the following command:

./mkbootimage --zynqmp boot.bif boot.bin

will generate a .bin image, which can be used to successfully boot a Zynq UltraScale+ machine, and to boot Linux using the following U-Boot command:

bootm 0x3000000 0x2000000 0x2a00000

Encryption certificates are not supported.

exbootimage

exbootimage parses a boot ROM file and extracts desired information out of it.

To use it, type in:

./exbootimage [--zynqmp|-u]   [--extract|-x] [--force|-f]  [--list|-l]
              [--describe|-d] [--header|-h]  [--images|-i] [--parts|-p]
              [--bitstream|-d DESIGN,PART-NAME]
              <input_bif_file> [extract_file...]

To see all available options, run:

./exbootimage --help

Three of the main functionalities of the tool are described below.

Listing the contents of the boot image

To list the contents of the boot image use the -l option. It is especially useful before extracting partitions.

To obtain the list, run:

./exbootimage -l boot.bin

Printing a description of headers of the boot image

You can print a readable description of all headers in a boot image by using the -d option.

The output is divided into sections dedicated to various header types:

1. Main file header
2. Image header table
3. Image headers
4. Partition headers

To see it working, run:

./exbootimage -d boot.bin

Or for ZynqMP bootimages:

./exbootimage -u -d boot.bin

Extracting partition data

To extract partition contents use the -x option. The partitions will be extracted into files named after each partition's image name.

To perform this operation, run:

./exbootimage -x boot.bin

Or for ZynqMP boot files:

./exbootimage -ux boot.bin

The tool stops if a file of that name is already present, this behaviour can be bypassed with the -f flag:

./exbootimage -uxf boot.bin

To extract only some of the partitions, type their names after the boot image name:

./exbootimage -x boot.bin fpga.bit rootfs.img