No Internet access through Ethernet with Linux Kernel 4.14

yoro0

Hi,

I am upgrading my custom board which uses a Cyclone V SoCFPGA from linux 3.10-ltsi to linux 4.14.73-ltsi and I am having difficulties in getting it connected to the internet.

It seems to be a network configuration issue and that's why I am writing on this forum. (The official support is also extremely slow/close to non-existent).

I get the message "failed to bring up eth0" when dhcp tries to assign an IP to the unit.

It only works in one case as described below. Also some other observations are written below;

NOTE: we have 2 sectors on the flash memory where we can store images.

a) If we boot from the 1st sector (containing kernel version 3.10-ltsi), ethernet connection and access to the internet is established successfully. If we do a warm reboot (i.e rebooting just the SoC) and boot to sector 2 (containing the linux kernel version 4.14.73-ltsi) the ethernet connection and access to the internet is established successfully.

b) if we keep warm rebooting the unit with kernel 4.14, the internet connection is always established properly.

c) If we do a cold reset (i.e resetting the EMAC, QSPI etc… just like a pulling the power plug) and boot straight to the linux kernel 4.14.73-ltsi then the ethernet connection is established but when dhcp runs we get the error message “Failed to bring up eth0”. Setting a static IP does not work either. So no packets get out!

d) Putting down eth0 by using commands like (ifconfig eth0 down or ifdown --force eth0) will cause the system to immediately COLD RESET! which is very strange.

Here is my dmesg log https://0bin.net/paste/PkLJgwlBFOuAzQQk#6KbzDd1yCUEqz0u-FX0WKuW7J65rBOXVJJuNdFLD2Qn

I would be really grateful if someone could point me to what could be the issue. I have been struggling with this for a while now.