Intel i225 NVM update under Linux

[Tomi61]

We have a custom made hw with an Intel Atom processor running our company specific Linux distribution. We are using the i225 ethernet controller and sometimes having connection issues, namely the link does not come up at all when connecting the cable. Interestingly, this issue happens just when the other side uses an Intel ethernet controller as well. As it was discovered this is a known issue and Intel suggest an NVM firmware update of the i225. My questions are as below:

1. We have the 'eeupdate64' binary, which cannot be used under our custom Linux (using musl libraries). Would it be possible to build it ourself with our libraries?

2. If #1 is not an option, there is the EepromAccessTool, which is open-source (although we don't have the sources right now). Could we use EepromAccessTool to update the NVM image? If so, how could we download the sources?
3. Could you please clarify the root cause of this „unable to establish connection” issue of the i225?

[Tomi61]

Meanwhile, we were able to solve my questions under points #1 and #2 in my original post and updated the NVM image of the i225 successfully. With the updated fw image the i225 started to work, the previously dead ports in our devices can be connected and pinged. So far so good. The only question remained is the root cause of the issue. Originally we used  fw: 1.57 and upgraded to fw: 1.94. What was changed in the 1.94 fw version which made the chip work?