Intel® SoC FPGA Embedded Development Suite (SoC EDS) User Guide

ID 683187
Date 3/12/2021
Document Table of Contents

6.4. U-Boot Image Tool (mkimage)

Both the FSBL and SSBL require the presence of the U-Boot image header at the beginning of the next stage boot image. Depending on usage scenario, other items that are loaded by either Preloader or Bootloader may also require the presence of the U-Boot image header.

The mkimage utility can be built with U-Boot by following instructions from the Building Bootloader web page on RocketBoards. Note: You can also use this prebuilt version: mkimage utility. The mkimage utility can be used to append the U-Boot image header to the next stage boot image or any other required files.

Figure 25. mkimage Header

The header consists of the following items:

  • Image magic number - determines if the image is a valid boot image
  • Image data size - the length of the image to be copied
  • Data load address - the entry point of the boot image (not used for items that are not bootable images)
  • Operating system - determines the type of image
  • Image name - the name of the boot image
  • Image CRC - the checksum value of the boot image
Figure 26. mkimage Header Layout