Modification of tegra234-p3768 Device Tree Source Not Taking Effect

Issue Overview

The issue discussed in the forum revolves around users attempting to modify the device tree source (DTS) for the Nvidia Jetson Orin Nano development board (model p3768). The specific symptoms reported include:

• Users modified the file located at hardware/nvidia/platform/t23x/p3768/kernel-dts/cvb/tegra234-p3768-0000-a0.dtsi.
• After compiling and flashing the board, the changes made to the device tree did not reflect when checking the contents of /sys/firmware/devicetree/base/.
• The problem occurs during the setup process, specifically after following a series of steps intended to apply modifications to the device tree.

The hardware in question is the Nvidia Jetson Orin Nano (p3768), and it appears that users consistently experience this issue after following the outlined steps. The impact on user experience is significant, as failure to apply these modifications can hinder functionality or performance of applications relying on specific hardware configurations.

Possible Causes

Several potential causes may lead to the observed problem:

• Hardware Incompatibilities or Defects: If there are hardware issues with the board itself, modifications may not take effect as expected.

• Software Bugs or Conflicts: There may be bugs in the software tools used for flashing or compiling that prevent successful updates to the device tree.

• Configuration Errors: Incorrect parameters or paths during the flashing process could lead to changes not being applied.

• Driver Issues: Outdated or incompatible drivers may interfere with device tree modifications.

• Environmental Factors: Power supply issues or overheating could affect the flashing process.

• User Errors or Misconfigurations: Mistakes in following the flashing procedure can lead to unsuccessful updates.

Each of these causes could result in the failure of modifications to take effect, as they may prevent proper communication between software and hardware components.

Troubleshooting Steps, Solutions & Fixes

To address this issue, users can follow these comprehensive troubleshooting steps:

1. Verify File Modifications:

   • Ensure that changes were correctly made to tegra234-p3768-0000-a0.dtsi. Check for syntax errors or incorrect configurations.

2. Recompile and Flash:

   • Execute the compilation command again:

     ./nvbuild.sh -o <kernel compilation directory>
     

   • Ensure that you are copying the correct compiled device tree files:

     cp <kernel compilation directory>/arch/arm64/boot/dts/nvidia/* <kernel/dtb directory>
     

3. Check Flashing Command:

   • Review and execute the flashing command carefully:

     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" --showlogs --network usb0 jetson-orin-nano-devkit internal
     

4. Inspect Logs for Errors:

   • After flashing, check logs for any errors that occurred during the process which might indicate what went wrong.

5. Check Device Tree Output:

   • After rebooting, check if changes are reflected by inspecting:

     ls /sys/firmware/devicetree/base/
     

6. Test with Different Configurations:

   • If issues persist, attempt testing with a different version of JetPack or using a different Orin Nano board if available.

7. Update Drivers and Firmware:

   • Ensure that all drivers and firmware are up-to-date. Refer to Nvidia’s official documentation for updates.

8. Consult Community Forums:

   • If unresolved, consider posting detailed findings in dedicated forums such as Nvidia’s Jetson forums for community support.

9. Document Any Unresolved Issues:

   • Keep track of any specific errors or behaviors encountered during these steps for further investigation or community assistance.

By following these steps systematically, users should be able to diagnose and potentially resolve issues related to device tree modifications on their Nvidia Jetson Orin Nano development boards.