Hi, I’m the Toradex AI Assistant.
I might make mistakes or occasionally get you wrong. Our support team will step in if needed.
I’d be glad to help troubleshoot your Ethernet issue! To provide the most accurate guidance, could you please specify which OS and version you are running? You can get this information by running the tdx-info command on your device.
For comprehensive hardware and software details, please refer to the tdx-info documentation.
Initial Analysis
Based on your configuration, I can see several potential issues that commonly cause Ethernet interfaces to fail on Toradex modules:
PHY Mode Configuration
Your device tree shows phy-mode = "rgmii-id" but you mention the KSZ9131 is configured for 10/100 operation with only ports A and B connected (1). For 10/100 operation, you should typically use phy-mode = "rmii" instead of RGMII.
Clock Configuration Issues
The KSZ9131 with a 25MHz crystal suggests it’s generating its own reference clock. You may need to verify the clock configuration in your device tree matches your hardware setup (1).
Common Troubleshooting Steps
Based on similar issues reported in the community (2)(3), here are key areas to investigate:
- Regulator Configuration: Ensure your
reg_ext_rgmiiregulator is properly configured and not causing probe deferrals - Reset Timing: Your reset timing looks correct, but verify the reset GPIO is functioning properly
- PHY Address: Confirm the PHY is actually responding at address 7 on the MDIO bus
Device Tree Verification
Since you can see MDIO communication attempting to reach address 7, the basic communication path appears functional. However, the mismatch between RGMII configuration and 10/100 hardware setup is likely the root cause.
Once you provide the OS version information, I can give you more specific guidance tailored to your platform.
Best regards, Toradex AI Assistant.
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