PetaLinux

PetaLinux can be built for these reference designs with the cross-platform build.py runner at the root of the repository.

Requirements

To build the PetaLinux projects, you will need a physical or virtual machine running one of the supported Linux distributions as well as the Vitis Core Development Kit installed.

Attention

You cannot build the PetaLinux projects in the Windows operating system. Windows users are advised to use a Linux virtual machine to build the PetaLinux projects.

How to build

The build runner locates and sources the PetaLinux and Vivado settings itself, so there is no need to source them by hand. See the build instructions for the full description of the runner.

  1. From a command terminal, clone the Git repository (with its submodules) and cd into it:

    git clone --recurse-submodules https://github.com/fpgadeveloper/ethernet-fmc-max-axi-eth.git
cd ethernet-fmc-max-axi-eth

  2. Build the PetaLinux image for your target by running the following command and replacing <target> with one of the target design labels found in the build instructions:

    ./build.sh petalinux --target <target>

This will also launch the build process for the corresponding Vivado project if that project has not already been built and its hardware exported.

Boot a MicroBlaze design (auboard, kcu105_hpc, vcu118_fmcp)

The MicroBlaze designs do not boot from SD; instead the PetaLinux build packages images/linux/boot.mcs, which is programmed into the board’s QSPIx4 flash. The kernel uses an initramfs root, so no SD card is needed. See PetaLinux/Makefile (flash-size column) for the per-board flash size (32 MB on KCU105, 64 MB on AUBoard, 128 MB on VCU118).

The simplest way to bring one of these targets up the first time is via JTAG; see Boot via JTAG below. For production flashing, program boot.mcs into QSPI using Vivado’s Hardware Manager.

Boot from SD card (Zynq UltraScale+ and Versal)

Prepare the SD card

Once the build process is complete, you must prepare the SD card for booting PetaLinux.

  1. The SD card must first be prepared with two partitions: one for the boot files and another for the root file system.

    • Plug the SD card into your computer and find it’s device name using the dmesg command. The SD card should be found at the end of the log, and it’s device name should be something like /dev/sdX, where X is a letter such as a,b,c,d, etc. Note that you should replace the X in the following instructions.

Warning

Do not continue these steps until you are certain that you have found the correct device name for the SD card. If you use the wrong device name in the following steps, you risk losing data on one of your hard drives.

  • Run fdisk by typing the command sudo fdisk /dev/sdX

  • Make the boot partition: typing n to create a new partition, then type p to make it primary, then use the default partition number and first sector. For the last sector, type +1G to allocate 1GB to this partition.

  • Make the boot partition bootable by typing a

  • Make the root partition: typing n to create a new partition, then type p to make it primary, then use the default partition number, first sector and last sector.

  • Save the partition table by typing w

  • Format the boot partition (FAT32) by typing sudo mkfs.vfat -F 32 -n boot /dev/sdX1

  • Format the root partition (ext4) by typing sudo mkfs.ext4 -L root /dev/sdX2

  1. Copy the following files to the boot partition of the SD card: Assuming the boot partition was mounted to /media/user/boot, follow these instructions:

    $ cd /media/user/boot/
$ sudo cp /<petalinux-project>/images/linux/BOOT.BIN .
$ sudo cp /<petalinux-project>/images/linux/boot.scr .
$ sudo cp /<petalinux-project>/images/linux/image.ub .

  2. Create the root file system by extracting the rootfs.tar.gz file to the root partition. Assuming the root partition was mounted to /media/user/root, follow these instructions:

    $ cd /media/user/root/
$ sudo cp /<petalinux-project>/images/linux/rootfs.tar.gz .
$ sudo tar xvf rootfs.tar.gz -C .
$ sync

    Once the sync command returns, you will be able to eject the SD card from the machine.

Boot PetaLinux

  1. Plug the SD card into your target board.

  2. Ensure that the target board is configured to boot from SD card:

    • VCK190, VMK180, VEK280, VPK120: DIP switch SW1 is set to 1000 (1=ON,2=OFF,3=OFF,4=OFF)

    • UltraZed-EV: DIP switch SW2 (on the SoM) is set to 1000 (1=ON,2=OFF,3=OFF,4=OFF)

    • ZCU102, ZCU104, ZCU106, ZCU111: DIP switch SW6 must be set to 1000 (1=ON,2=OFF,3=OFF,4=OFF)

    • ZCU208, ZCU216: DIP switch SW2 must be set to 1000 (1=ON,2=OFF,3=OFF,4=OFF)

  3. Connect the Ethernet FMC Max to the FMC connector of the target board.

  4. Connect the USB-UART to your PC and then open a UART terminal set to 115200 baud and the comport that corresponds to your target board.

  5. Connect and power your hardware.

Boot via JTAG

Tip

You need to install the cable drivers before being able to boot via JTAG. Note that the Vitis installer does not automatically install the cable drivers, it must be done separately. For instructions, read section installing the cable drivers from the Vivado release notes.

Warning

If you boot the Zynq UltraScale+ or Zynq RFSoC designs via JTAG, you must still first prepare the SD card. The reason is because these designs are configured to use the SD card to store the root filesystem. If you boot these designs via JTAG without preparing and connecting the SD card, the boot will hang at a message similar to this: Waiting for root device /dev/mmcblk0p2... The Versal and MicroBlaze designs use an initramfs root and do not require the SD card to boot.

Setup hardware

  1. For Zynq UltraScale+ and RFSoC targets, prepare the SD card according to the instructions above and plug it into the target board. The Versal and MicroBlaze designs use an initramfs root and do not require an SD card for JTAG boot.

  2. Ensure that the target board is configured to boot from JTAG:

    • VCK190, VMK180, VEK280, VPK120: DIP switch SW1 is set to 1111 (1=ON,2=ON,3=ON,4=ON)

    • UltraZed-EV: DIP switch SW2 (on the SoM) is set to 1111 (1=ON,2=ON,3=ON,4=ON)

    • ZCU102, ZCU104, ZCU106, ZCU111: DIP switch SW6 must be set to 1111 (1=ON,2=ON,3=ON,4=ON)

    • ZCU208, ZCU216: DIP switch SW2 must be set to 1111 (1=ON,2=ON,3=ON,4=ON)

    • AUBoard, KCU105, VCU118: MicroBlaze targets boot via JTAG by default once the bitstream is loaded; no boot-mode switch needs to change. (For long-term standalone operation, program boot.mcs into the on-board SPIx4 flash.)

  3. Connect the Ethernet FMC Max to the FMC connector of the target board.

  4. Connect the USB-UART to your PC and then open a UART terminal set to 115200 baud and the comport that corresponds to your target board.

  5. Connect and power your hardware.

Boot PetaLinux

To boot PetaLinux on hardware via JTAG, use the following commands in a Linux command terminal:

  1. Change current directory to the PetaLinux project directory for your target design:

    cd <project-dir>/PetaLinux/<target>

  2. Download bitstream to the FPGA:

    petalinux-boot --jtag --kernel --fpga

An explanation of the above command is provided by the petalinux-boot command:

For microblaze, it will download the bitstream to target board, and
then boot the kernel image on target board.
For Zynq, it will download the bitstream and FSBL to target board,
and then boot the u-boot and then the kernel on target
board.
For Zynq UltraScale+, it will download the bitstream, PMUFW and FSBL,
and then boot the kernel with help of linux-boot.elf to set kernel
start and dtb addresses.

UART terminal

You will need to setup a terminal emulator to use the PetaLinux command line over the USB-UART connection. Connect with a baud rate of 115200.

In Windows

You will need to find the comport for the USB-UART in Windows Device Manager. As a terminal emulator, you can use the open source and free Putty.

In Linux

In Linux, you can find the USB-UART device by running dmesg | grep tty. Typically, the device will be /dev/ttyUSB0 or it could be followed by a different number. To open a terminal emulator, you can use the following command:

sudo screen /dev/ttyUSB0 115200

Port configurations

PetaLinux 2025.2 renames the network interfaces from the legacy ethN names to predictable endN names early in boot (you’ll see renamed from ethN lines in the kernel log). The endN mapping is what ifconfig and ip link will show.

The default interfaces table (/etc/network/interfaces) brings up end0 at boot, so it is convenient to wire end0 to a DHCP-enabled link before powering the board.

Zynq UltraScale+ designs (uzev, zcu102, zcu106, zcu111, zcu208, zcu216)

Four-port variants (ports-0123):

  • end0: Ethernet FMC Max Port 1 (PHY @ MDIO addr 3)

  • end1: Ethernet FMC Max Port 2 (PHY @ MDIO addr 12)

  • end2: Ethernet FMC Max Port 3 (PHY @ MDIO addr 15)

  • end3: GEM3 onboard Ethernet port of the dev board

  • end4: Ethernet FMC Max Port 0 (PHY @ MDIO addr 1, master MDIO bus)

Zynq UltraScale+ single-port design (zcu104)

The ZCU104 routes only one Ethernet lane through its LPC FMC slot, so the ports-0xxx overlay enables only Port 0:

  • end0: GEM3 onboard Ethernet port of the dev board

  • end1: Ethernet FMC Max Port 0 (PHY @ MDIO addr 1)

Versal designs (vck190, vmk180, vek280, vhk158, vpk120, vpk180)

  • end0: Ethernet FMC Max Port 0 (PHY @ MDIO addr 1, master MDIO bus)

  • end1: Ethernet FMC Max Port 1 (PHY @ MDIO addr 3)

  • end2: Ethernet FMC Max Port 2 (PHY @ MDIO addr 12)

  • end3: Ethernet FMC Max Port 3 (PHY @ MDIO addr 15)

  • end4: GEM0 onboard Ethernet port of the dev board

  • end5: GEM1 onboard Ethernet port of the dev board (when wired)

The four FMC ports share a single MDIO bus rooted at axi_ethernet_0; the remaining axi_ethernet_N nodes have xlnx,has-mdio = <0x1> but an empty local MDIO node (see PetaLinux/bsp/ports-0123/.../port-config.dtsi).

Example Usage

The examples below are from a ZCU102 PetaLinux session. On Versal the interface names map differently — see the Port configurations section above.

Enable port

This example will bring up a port.

root@zcu102-axieth-sgmii-2025-2:~# sudo ifconfig end4 up
[  228.274146] xilinx_axienet a0000000.ethernet end4: Link is Up - 1Gbps/Full - flow control off
[  228.282753] IPv6: ADDRCONF(NETDEV_CHANGE): end4: link becomes ready

Enable port with fixed IP address

This example sets a fixed IP address to a port.

root@zcu102-axieth-sgmii-2025-2:~# sudo ifconfig end4 192.168.2.30 up
[  390.080498] net end4: Promiscuous mode disabled.
[  390.085406] net end4: Promiscuous mode disabled.
[  390.091089] xilinx_axienet a0000000.ethernet end4: Link is Down
[  394.175238] xilinx_axienet a0000000.ethernet end4: Link is Up - 1Gbps/Full - flow control off
[  394.183769] IPv6: ADDRCONF(NETDEV_CHANGE): end4: link becomes ready

Enable port using DHCP

This example enables a port and obtains an IP address for the port via DHCP. Note that the port must be connected to a DHCP enabled router.

root@zcu102-axieth-sgmii-2025-2:~# sudo udhcpc -i end4
udhcpc: started, v1.36.1
[   68.814013] xilinx_axienet a0000000.ethernet end4: Link is Up - 1Gbps/Full - flow control off
[   68.822670] IPv6: ADDRCONF(NETDEV_CHANGE): end4: link becomes ready
udhcpc: sending discover
udhcpc: sending select for 192.168.2.72
udhcpc: lease of 192.168.2.72 obtained, lease time 259200
/etc/udhcpc.d/50default: Adding DNS 192.168.2.1

Check port status

In this example, we use the ifconfig command with no arguments to check the port status. Trimmed excerpt — end3 is the onboard GEM3 (not enabled), end4 is Ethernet FMC Max port 0 brought up at 192.168.2.30:

root@zcu102-axieth-sgmii-2025-2:~# ifconfig
end3      Link encap:Ethernet  HWaddr A6:D3:33:F0:90:3B
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
          Interrupt:50

end4      Link encap:Ethernet  HWaddr 00:0A:35:00:01:22
          inet addr:192.168.2.30  Bcast:192.168.2.255  Mask:255.255.255.0
          inet6 addr: fe80::20a:35ff:fe00:122/64 Scope:Link
          UP BROADCAST RUNNING  MTU:1500  Metric:1
          RX packets:38 errors:0 dropped:0 overruns:0 frame:0
          TX packets:26 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:6033 (5.8 KiB)  TX bytes:3302 (3.2 KiB)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          ...

We can also use ethtool to check the port status as follows.

root@zcu102-axieth-sgmii-2025-2:~# ethtool end4
Settings for end4:
        Supported ports: [ TP MII FIBRE ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Supported pause frame use: Symmetric Receive-only
        Supports auto-negotiation: Yes
        Supported FEC modes: Not reported
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Advertised FEC modes: Not reported
        Link partner advertised link modes:  10baseT/Half 10baseT/Full
                                             100baseT/Half 100baseT/Full
                                             1000baseT/Full
        Link partner advertised pause frame use: No
        Link partner advertised auto-negotiation: Yes
        Link partner advertised FEC modes: Not reported
        Speed: 1000Mb/s
        Duplex: Full
        Port: MII
        PHYAD: 0
        Transceiver: internal
        Auto-negotiation: on
        Link detected: yes