04 Minimal Linux System from AMD Petalinux on TE0950 Board

AMD Vivado™ Project

For steps to create the Vivado Design. We are using the Vivado design from the previous project which only contains the Processor System represented by the CIPS IP and the NoC IP which include the Memory Controller to access the DDR.

In the Flow navigator, click on Generate Device Image to generate the XSA that we will then feed to AMD petalinux™

AMD Petalinux™ Introduction

To create the Linux image, you have multiple option. You can use a generic tool like buildroot or use Yocto or Petalinux.

The AMD PetaLinux Tools offers everything necessary to customize, build and deploy Embedded Linux solutions on AMD processing systems. One thing to note is that Petalinux is based on Yocto (I might build the linux image using Yocto in a next project).

It is important to note that AMD consider Petalinux only as an evaluation tool and stated that it should not be used in production system:

https://xilinx-wiki.atlassian.net/wiki/spaces/A/pages/2741928025/Moving+from+PetaLinux+to+Production+Deployment

AMD Petalinux™ Project

Create a petalinux project with Versal template using the following command

petalinux-create project --template versal --name TE0950_basic_petalinux

Then cd into the petalinux project directory

Import the hardware configuration using the XSA:

petalinux-config --get-hw-description TE0950_Designs/03_TE0950_Basic_Linux/vivado/build/TE0950_basic_DDR.xsa

In the Petalinux configuration wizard, under Image Packaging Configuration, change the following settings to let PetaLinux generate EXT4 rootfs.

• Set Root File System Type to EXT4
• Set Root filesystem formats to ext4 tar.gz
• Set Device node of SD device to /dev/mmcblk1p2

Note: This last setting is because the SD card is connected to the second SD controller of the Processing System on the TE0950 board

To allow Linux to boot from EXT4 partition we need to change the bootargs settings. Under DT settings > Kernel Bootargs:

• Set generate boot args automatically to No
• Set user set kernel bootargs to console=ttyAMA0 earlycon=pl011,mmio32,0xFF010000,115200n8 clk_ignore_unused root=/dev/mmcblk1p2 rw rootwait cma=512

Add the board device tree file by copying the file from https://github.com/xflorentw/TE0950_Designs/blob/main/03_TE0950_Basic_Linux/os/petalinux/src/recipes-bsp/device-tree/files/TE0950.dtsi

Note: This device tree file contains the node for the peripherals which are on the TE095 board so Linux is aware of them

Open the file TE0950_basic_petalinux/project-spec/meta-user/recipes-bsp/device-tree/device-tree.bbappend and change the following line

SRC_URI:append = "file://system-user.dtsi"

to

SRC_URI:append = "file://system-user.dtsi file://TE0950.dtsi"

With this, the board device tree file is included in the list of source files

Open the file TE0950_basic_petalinux/project-spec/meta-user/recipes-bsp/device-tree/files/system-user.dtsi and add the following line at the top of the file:

/include/ "TE0950.dtsi"

Build the petalinux project

petalinux-build

Package the linux boot image

petalinux-package boot --u-boot

And finally, create an SD Card image

petalinux-package wic

On Windows, use a tool to write SD Card such as Win32DiskImager and burn the SD Card using the petalinux-sdimage.wic SD Card image file which is located under TE0950_basic_petalinux/images/linux

Insert the SD Card in the TE0950 board and ensure the boot mode is set to SD card

• S2 [1:3] - [OFF, ON, OFF] - JTAG Boot

Power On the TE0950 board and open a UART terminal (for example Tera Term) can connect to the COM port corresponding to the TE0950 board with the following settings

• Speed: 115200
• Data: 8-bit
• Parity: None
• Stop Bits: 1 bit

You will see Linux booting correctly up to the linux prompt

So we have now a working linux system we can move to the next step which will be to build an acceleration system including the AI Engine

The full project can be build from Makefile and is available on my github repository

https://github.com/xflorentw/TE0950_Designs/tree/main/03_TE0950_Basic_Linux

Disclaimers

• AMD, Versal, and Vitis are trademarks or registered trademarks of Advanced Micro Devices, Inc.
• Other product names used in this publication are for identification purposes only and may be trademarks of their respective companies.