Where is tegra_pinctrl_reg in Orin Nano?

Issue Overview

Users are experiencing difficulties in accessing the tegra_pinctrl_reg register on the Nvidia Jetson Orin Nano Dev board, which is crucial for pinmux configuration. Specifically, they are unable to find the register address and value, which were accessible on previous models like the Xavier NX and Nano. The issue arises during attempts to change pinmux settings via command line, with users reporting that commands that worked on older models do not yield results on the Orin Nano. The symptoms include failure to retrieve register addresses and values when executing commands such as:

sudo cat /sys/kernel/debug/pinctrl/2430000.pinmux/pinconf-groups

Users have noted that this problem is consistent and impacts their ability to configure hardware settings effectively, leading to frustration and halted development processes.

Possible Causes

1. Hardware Incompatibilities: The Orin Nano may have different hardware architecture compared to previous models, leading to changes in how pinmux settings are accessed.
2. Software Bugs or Conflicts: There could be bugs in the current software or firmware that prevent access to certain registers.
3. Configuration Errors: Users might be using incorrect commands or paths that do not apply to the Orin Nano.
4. Driver Issues: Outdated or incompatible drivers could hinder access to hardware registers.
5. Environmental Factors: Power supply issues or overheating may affect board performance and functionality.
6. User Errors: Misunderstanding of new command structures or paths specific to the Orin Nano could lead to failed attempts at accessing registers.

Troubleshooting Steps, Solutions & Fixes

1. Verify Command Syntax:

   • Ensure that you are using the correct command syntax for the Orin Nano. For checking pinmux configuration, use:

     sudo cat /sys/kernel/debug/pinctrl/2430000.pinmux/pinconf-groups
     

   • If this command does not return expected results, verify if the path is correct.

2. Use Alternative Commands:

   • To change pinmux settings directly, use the devmem command as follows (after determining the correct register address from the Technical Reference Manual):

     sudo busybox devmem <register_address> 32 <value>
     

   • Example for enabling a specific pin:

     sudo busybox devmem 0x02431020 32 0x00000400
     

3. Consult Technical Reference Manual (TRM):

   • Search for the correct pinmux register addresses in the TRM document specific to the Jetson Orin Nano.

4. Check Driver Installation:

   • Ensure that all necessary drivers are installed and up-to-date. Use JetPack SDK Manager for installation and updates.

5. Reboot and Retry:

   • Sometimes a simple reboot can resolve temporary issues with accessing hardware resources.

6. Testing with Different Configurations:

   • If possible, test with different SD cards or configurations to rule out any issues with your current setup.

7. Engage with Community Support:

   • Post detailed queries on forums like Nvidia Developer Forums for community support and insights from other developers who might have faced similar issues.

8. Documentation Links:

   • Refer to Nvidia’s official documentation for Jetson Orin Nano for additional guidance on configuration and troubleshooting:
     • Nvidia Jetson Documentation

9. Best Practices:

   • Always ensure your board is properly powered and cooled to avoid environmental factors affecting performance.
   • Keep your software environment clean and regularly update your development tools.

10. Unresolved Aspects:

    • Further investigation may be needed into whether this issue is a known bug in the current firmware version of JetPack being used.

By following these steps, users should be able to diagnose and potentially resolve their issues with accessing pinmux configurations on the Nvidia Jetson Orin Nano Dev board effectively.