Scope of Work

The purpose of this page is to describe how to boot ZCU102 using USB boot mode. Here two ZCU102 boards are connected back-to-back and configured as USB Host and Device. This can be done by setting ZCU102 device board in USB Boot mode and using DFU utility. Binaries like PMUFW, FSBL, U-Boot, ATF, Linux kernel, Device Tree and Rootfs are downloaded through DFU utility from Host.

Table of Contents

Introduction

Zynq UltraScale+ MPSoC, the next generation Zynq device, comes with a versatile Processing System (PS) integrated with a highly flexible and high-performance Programmable Logic (PL) section, all on a single system-on-a-chip (SoC).

Zynq Ultrascale+ MPSoC also supports USB Slave Boot Mode. This is using the USB DFU Device Firmware Upgrade (DFU) Device Class Specification of USB. Using a standard update utility such as DFU-Util, you will be able to load the newly created image on Zynq UltraScale+ via the USB Port of another Zynq Ultrascale+

Prerequisites

• Vitis Tool

• PetaLinux

• Back-to-Back USB 3.0 Cable

• Two ZCU102 boards

HW Test Environment

Connect two ZCU102 boards using USB 3.0 back-to-back setup. One in host mode and another in device mode.

ZCU102 Host

Jumper settings for Host mode

1. J7 - 1-2 Close

2. J113 - 1-2 Close

3. J110 - 2-3 Close

Please refer the image below for Host Mode jumper settings

Open

ZCU102 Device

Jumper settings for Peripheral mode

1. J7 – 1-2 Open

2. J113 - 1-2 Close

3. J110 - 1-2 Close

4. Set USB Boot mode by setting SW6 (1-OFF, 2-OFF, 3-OFF, and 4-ON) as  shown below

Please refer the image below for Device Mode jumper settings

Open

Please refer image below for Switch settings to set Device in USB Boot mode

Please refer the image below for ZCU102 USB Back-to-Back setup

Test Version

• Example tested with Vitis 2021.1

• PetaLinux Project is based on 2021.1

Software Build Procedure

The following procedure is for USB Non Secure Boot Mode. The process to create Secure Binaries and Boot via USB DFU will be added to this wiki in future.

PetaLinux Tool Steps

Create and Configure PetaLinux Project

Create PetaLinux Project

Create PetaLinux project with 2021.1 bsp using the command below

Configure PetaLinux

Configure PetaLinux with command below

Save and Exit to create petalinux-config file.

Build PetaLinux with dfu-util utility for ZCU102 Host

Add dfu-util utility to user-rootfsconfig file

• Enable dfu-util in PetaLinux

• Add CONFIG_dfu-util to the last line of <PetaLinux Project>/project-spec/meta-user/conf/user-rootfsconfig

Please refer the below sample file

Enable dfu-util utility in rootfs

• petalinux-config -c rootfs ->Configuration ->user packages ->dfu-util

• Select “dfu-util” in “user-packages”. Please refer to the image below,

Build PetaLinux

• Build PetaLinux with changes

• Create a copy of host binaries

Build PetaLinux with Device Mode changes for ZCU102 Device

Enable Device Mode

Modify PetaLinux U-Boot so that it can load the linux images. The Device tree needs to be modified to set USB in the peripheral mode. The default PetaLinux configuration is set for the USB in Host mode.

For this, follow the below steps to modify system-user.dtsi in the PetaLinux Project

Add the following code to <PetaLinux-project>/project-spec/meta-user/recipes-bsp/device-tree/files/system-user.dtsi, so that it looks like:

Build PetaLinux

• Build PetaLinux with changes.

Vitis Tool Steps

Create FSBL Application Project

• Use the information provided below to make your selections in the wizard. Please refer to the image below,

• In Vitis, select File > New > Application Project to open the New Project wizard.

• Create new platform from hardware(XSA) from <PetaLinux Project>/project-spec/hw-description/system.xsa file. Please refer to the image below,

• Provide Application Project Name, please refer below image

• Select Zynq MP FSBL template, please refer below image

• Click Finish

Configure FSBL to Enable USB Boot Mode

1. In the Project Explorer tab, expand the fsbl_usb_boot project and open xfsbl_config.h from: fsbl_usb_boot > src > xfsbl_config.h

2. In xfsbl_config.h change or set following settings:

3. Use CTRL + S to save these changes

4. Select Release and Build FSBL (fsbl_usb_boot)

Please refer image below for reference

Create Boot Image with FSBL

In this section, you will create the Boot Images to be loaded, via USB using DFU utility. Device Firmware Upgrade (DFU) is intended to download and upload firmware to/from devices connected over USB. In this boot mode, the Boot loader (FSBL) and the PMUFW which are loaded by Boot ROM are copied to ZCU102 Device’s On Chip Memory (OCM) from ZCU102 Host’s USB port using DFU Utility. The size of OCM (256 KB) limits the size of boot image downloaded by BootROM in USB boot mode. Considering this, and subject to size requirement being met, only FSBL and PMUFW are stitched into the first BOOT.bin, which is copied to OCM. Rest of the Boot partitions will be stitched in another Boot image and copied to DDR to be loaded by the FSBL which is already loaded and running at this stage.

Follow the below steps to Create Boot Images for this boot mode.

• In Vitis, select Xilinx > Create Boot Image.

• BOOT.bin can be created either by Import from existing BIF file or Create new BIF file

• Import from existing BIF file can be used by providing the BOOT.bif as input and files path can be edited accordingly.

• Please refer the BOOT.bif code provided below for reference.

• To create a new BIF file, select Create new BIF file and add the fsbl_usb_boot.elf and pmu_fw.elf partitions.

• Select FSBL from <Vitis workspace path>/fsbl_usb_boot/Release/fsbl_usb_boot.elf

• Select PMUFW from <PetaLinux Project>/images/linux/pmufw.elf

• PetaLinux <PetaLinux Project>/pre-built/linux/images/pmufw.elf can also be used to create BOOT.bin

• Select FSBL and PMUFW partitions and set them as shown in the following figure.

• Click on Create Image to generate BOOT.bin

Create Boot Image with U-Boot

The following steps describe how to create usb_boot.bin.

• In Vitis, select Xilinx > Create Boot Image.

• usb_boot.bin can be created either from Import from existing BIF file or Create new BIF file

• Import from existing BIF file can be used by providing the usb_boot.bif as input and files path can be edited accordingly.

• Please refer the usb_boot.bif code provided below for reference.

• To create a new BIF file, select Create new BIF file and add the fsbl_usb_boot.elf, pmu_fw.elf, bl31.elf, u-boot.elf and system.dtb partitions.

• Select FSBL from <Vitis workspace path>/fsbl_usb_boot/Release/fsbl_usb_boot.elf

• Select PMUFW from <PetaLinux Project>/images/linux/pmufw.elf

• Select ATF from <PetaLinux Project>/images/linux/bl31.elf. Please refer below image,

• Select U-BOOT from <PetaLinux Project>/images/linux/u-boot.elf. Please refer below image,

• Select DTB from <PetaLinux Project>/images/linux/system.dtb. Please refer below image,

• Select the partitions and set them as shown in the following figure.

• Click on Create Image to generate usb_boot.bin

Test Procedure

Boot ZCU102 Host

• Boot Host with dfu-util enabled PetaLinux images.

• Copy Device’s binaries (BOOT.bin, usb_boot.bin, Image, rootfs.cpio.gz.u-boot and system.dtb) to SD Card and insert it into SD slot of Host.

Check DFU detection on Host

• Check if the Host’s DFU can detect the USB target.

Download Binaries to Device

Download PMUFW and FSBL

Download U-Boot and ATF

Enable Rootfs Download on Device

• On Device’s U-Boot console, modify dfu_ram_info to enable rootfs download via DFU.

• Verify the dfu_ram_info using printenv.

Download Linux Image

Download DTB

Download ROOTFS

Boot ZCU102 Device

• On Device, Boot Linux with booti command on U-Boot Console.

References

• https://www.xilinx.com/support/documentation/sw_manuals/xilinx2020_1/ug1209-embedded-design-tutorial.pdf