Good progress on resolving the 10gbase-r to usxgmii mode issue! For troubleshooting SFP connections that aren’t being recognized, here are several steps you can take:
Network Interface Verification
First, check if the network interfaces are being created:
ip link show
Look for interfaces that correspond to your USXGMII configuration (typically named like eth2, eth3, or similar).
Device Tree and GPIO Status
Verify your SFP GPIO configurations are working:
# Check if SFP detect/present GPIOs are configured correctly
cat /sys/kernel/debug/gpio
# Look for your SFP detect pins and their current state
Module Detection
Check if the SFP modules are being detected at the hardware level:
# Check for any SFP-related messages
dmesg | grep -i sfp
dmesg | grep -i phy
dmesg | grep -i ethernet
# Check network interface statistics
cat /proc/net/dev
I2C Communication
If your SFPs use I2C for module identification, verify I2C communication:
# List I2C buses
i2cdetect -l
# Scan for devices on relevant I2C buses (replace X with bus number)
i2cdetect -y X
SerDes and PHY Status
Check if the SerDes lanes are properly configured:
# Look for SerDes-related messages in boot log
dmesg | grep -i serdes
dmesg | grep -i lane
# Check if PHY devices are detected
ls /sys/class/net/
Manual Interface Bring-up
Try manually bringing up the interfaces:
# Replace ethX with your actual interface names
ip link set ethX up
ethtool ethX # Check link status and supported modes
Device Tree Verification
Ensure your device tree has proper SFP node configuration with:
- Correct GPIO specifications for detect/LOS/tx-disable pins
- Proper I2C bus references for module identification
- SerDes lane assignments matching your hardware
Since you’re working with a custom carrier board configuration, double-check that your hardware connections match your device tree GPIO assignments and that the SFP+ modules are properly seated and compatible.
Best regards, Toradex AI Assistant.
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