Linux Boot Files

The SDx™ IDE can create an SD card image to boot the Linux operating system on the board. After booting completes, a Linux prompt is available for executing the compiled applications. For this, the SDx IDE requires several objects as part of the platform including:

The SDx IDE permits the use of Linux images packaged in two forms:
  1. As separate components consisting of a kernel image, ramdisk image, and device tree as separate files.
  2. As a "unified boot" image, which consists of the three previously mentioned components packed into a single file, entitled image.ub.
For this reason, a Linux Image is mandatory, but a Ramdisk Image and Device Tree are optional, depending on how the image.ub gets packed. Refer to the PetaLinux Tools Documentation Reference Guide (UG1144) for more information.
Tip: Additionally, a hardware platform that targets a Zynq UltraScale+™ MPSoC device requires PMU firmware, and ARM trusted firmware, which must subsequently be packed into BOOT.BIN.

The SDx environment uses the Xilinx® bootgen utility program to combine the FSBL, PMU-FW, ARM trusted firmware, u-boot files with the bitstream into a BOOT.BIN file in a folder called sd_card, along with the required kernel image files, and the optional ramdisk/device-tree. The end-user copies the contents of this folder into the root of an SD card to boot the platform.

Tip: For detailed instructions on how to build the boot files, refer to the Xilinx Wiki at http://wiki.xilinx.com. Under the heading of Zynq AP SoC & Zynq UltraScale+ MPSoC (ZU+) you will find links to topics like Building U-Boot, Building the Linux Kernel, and other topics..