Concerns About USBSS Mapping and Configuration on Jetson Orin Nano Custom Board

Issue Overview

Users have reported concerns regarding the configuration and functionality of a custom-designed PCB based on the Nvidia Jetson Orin Nano (P3768-A04). The main issues include:

• Symptoms: Users are uncertain whether their design will function correctly, particularly regarding the mapping of USBSS ports and PCIe connections. There are concerns about potential conflicts between USBSS2 and PCIe ports.
• Context: The problem arises during the design and configuration phase, specifically when integrating various hardware components such as USB connectors, PCIe connections, and HDMI outputs.
• Hardware/Software Specifications: The custom board design includes multiple USB3.1 connectors, an NVMe connector for PCIe, and various removed components (like USB hubs and display ports). Users are utilizing files derived from jetson-nano-orin-devkit.conf for flashing configurations.
• Frequency: This issue appears to be common among users designing custom boards for the Orin Nano, reflecting a significant learning curve in understanding UPHY mapping options.
• Impact: The uncertainty surrounding hardware compatibility and configuration can lead to non-functional setups, affecting user experience and project timelines.

Possible Causes

Several potential causes may lead to the observed issues:

1. Hardware Incompatibilities: The removal of essential components (like USB hubs) may lead to improper mapping or conflicts within the design.

   • Explanation: Without proper hub circuitry, the board may not manage USB traffic effectively, causing devices to fail to communicate.

2. Configuration Errors: Incorrect settings in the UPHY mapping or device configurations can lead to malfunctions.

   • Explanation: Misconfigured UPHY settings can disrupt the expected operation of connected devices.

3. Driver Issues: Incompatibilities or bugs in driver software could prevent hardware from functioning correctly.

   • Explanation: If drivers do not support the custom configurations or specific hardware used, devices may not initialize properly.

4. User Errors: Lack of familiarity with Nvidia’s design specifications might lead to misconfigurations.

   • Explanation: Users may overlook critical details in documentation that guide proper setup.

5. Environmental Factors: Power supply inconsistencies or thermal issues could affect performance.

   • Explanation: Insufficient power delivery can cause devices to underperform or fail to initialize.

Troubleshooting Steps, Solutions & Fixes

To address the issues reported by users, follow these comprehensive troubleshooting steps:

1. Diagnosing the Problem:

   • Verify all connections against Nvidia’s reference designs for the Jetson Orin Nano.
   • Use terminal commands to check for device recognition:

     lsusb
     lspci
     

   • Inspect logs for errors related to USB or PCIe initialization:

     dmesg | grep -i usb
     dmesg | grep -i pci
     

2. Isolating the Issue:

   • Test individual components (USB devices, PCIe cards) on a known working system to confirm functionality.
   • Revert to a simpler configuration by temporarily removing non-essential components from the design.

3. Configuration Adjustments:

   • Review UPHY mapping options in your configuration files. Consider switching from USBSS2 to USBSS1 if conflicts are suspected.
   • Update configurations based on successful examples shared in forums or Nvidia documentation.

4. Flashing Firmware and Drivers:

   • Ensure you are using compatible versions of JetPack (preferably JetPack 5.x) that align with your hardware setup.
   • Flash using SDK Manager; ensure your board is in recovery mode during this process:

     sudo ./sdkmanager
     

5. Recommended Practices:

   • Regularly consult Nvidia’s developer forums for updates on common issues and solutions shared by other users.
   • Document any changes made during testing for future reference and troubleshooting.

6. Further Investigation:

   • If issues persist after following these steps, consider reaching out on Nvidia’s forums with detailed logs and descriptions of your setup for community support.
   • Explore potential hardware revisions based on feedback from experienced users.

By following these steps, users can better navigate the complexities of configuring their custom boards with the Nvidia Jetson Orin Nano platform while minimizing potential issues related to USBSS mapping and PCIe configurations.