Flashing Command for Custom Jetson Board: Explanation and Confirmation

Issue Overview

A user is seeking clarification on a flashing command for a custom board using Jetpack 5.1.1. The specific command in question is:

sudo ./tools/kernel_flash/l4t_initrd_flash.sh --external-device nvme0n1p1 -c tools/kernel_flash/flash_l4t_external.xml -p "-c bootloader/t186ref/cfg/flash_t234_qspi.xml" --no-flash --massflash 1 --network usb0 Manufacturing_testing_image internal

The user is unsure whether this command will flash the device or create system.img, boot.img, and recovery.img files. They need confirmation before proceeding with the flashing process.

Possible Causes

1. Misunderstanding of command functionality: The user may not be familiar with the specific options and their effects in the flashing command.
2. Lack of documentation: Insufficient or unclear documentation about the flashing process for custom Jetson boards.
3. Complexity of the flashing process: The multitude of options and parameters in the command can lead to confusion about its exact behavior.

Troubleshooting Steps, Solutions & Fixes

1. Command Explanation:

   • The command will not flash the device due to the --no-flash option.
   • It will create a tar file for mass flashing, as indicated by the --massflash 1 option.

2. Expected Behavior:

   • The command will generate necessary files for flashing, including system.img, boot.img, and recovery.img.
   • These files will be packaged into a tar file for mass flashing purposes.

3. Execution Time:

   • The duration of the command execution depends on the host PC’s performance.
   • Be prepared for it to take some time, especially if it’s your first run.

4. Device Mode:

   • Ensure the Jetson board is in Force Recovery Mode when running this command.
   • To enter Force Recovery Mode:
     a. Power off the device.
     b. Connect the appropriate pins on the board (refer to your specific model’s documentation).
     c. Power on the device while keeping the pins connected.

5. Understanding Flash Targets:

   • Navigate to the "Linux_for_Tegra/" directory.
   • Run ls -l jetson*.conf to view available flash targets.
   • The targets are named based on the module model and carrier board model.

6. Custom Carrier Boards:

   • If using a third-party carrier board, you may need a custom device tree.
   • This usually involves providing a different .conf file with customized content for the carrier board.

7. Checking L4T Release:

   • On the host PC: Go to "Linux_for_Tegra/rootfs/etc/" and run head -n 1 nv_tegra_release.
   • On the Jetson device: Run head -n 1 /etc/nv_tegra_release.

8. Debugging Tips:

   • Remove "quiet" from "/boot/extlinux/extlinux.conf" for verbose boot logs.
   • Consider installing a debug version of the boot software for more detailed boot stage information.
   • Always keep a copy of full serial console boot logs for future reference.

9. Device Tree Considerations:

   • Device trees are used in both boot stages and the operating system.
   • They provide arguments to hardware and drivers.
   • Incorrect device trees can result in partial system functionality.

10. Mass Flashing:

    • The --massflash option prepares the system for flashing multiple devices.
    • It creates a package that can be used to flash multiple Jetson boards efficiently.

By following these steps and understanding the command’s functionality, you can proceed with the flashing process more confidently. Remember to always back up important data before attempting any flashing or major system changes.