Banana Pi BPI-R4 (OpenWRT) logs failed to read EEPROM: -ENXIO and module slow to respond
On a Banana Pi BPI-R4 running OpenWRT 24.10.0 an SFP module failed with kernel logs failed to read EEPROM: -ENXIO and warnings that the module was slow to respond. The internet still worked but the log filled with the error, and the poster was unsure whether it pointed to a faulty stick, a GPON quirk needing a boot delay, or an I2C/power problem on the board's SFP cage.
- Hardware: Banana Pi BPI-R4
- Transceivers: SFP module (suspected GPON/XPON)
- Form factor: SFP
Symptoms / messages:
failed to read EEPROM: -ENXIO
module slow to respond
Comments 2
It is likely a GPON/XPON stick that needs a boot-delay quirk; use ethtool --dump-module-eeprom to get the vendor/product for a kernel quirk and check whether the secondary EEPROM at 0x51 (not 0x50) causes the error.
A related NVMe/I2C thread had the fix that helped the poster; also verify the I2C bus with i2cdetect, power delivery and firmware.