When I update the .sof image file into N3000-2 card with the method of JTAG and reboot the server machine，the FEC mode of card would return back to the default state ‘rs' ，which is wantd to be ’no'. Because in ‘rs' state the port are link down. If I modify it to ’no'，the card would update and rescan pcie address，which recovers the raw image and cleans up the .sof image I selected.
In early time of this year，we also met the question in another server. But it fixed in ’no' mode by accident and we don't do any special operations. However, this time this problem has lasted several days and makes us very upset.
How could I fix the mode of FEC？
I am able to observe the same. When FEC mode is changed, the cards performed RSU that reset the card. After reset, your programmed sof will not be loaded, instead the user image in the flash will be loaded.
Try to "fpgasupdate" the userimage, so that after you had configured the FEC to "no", it will return your desired user image with FEC=no.
Yes, fpgasupdate will take longer as it need to write to a staging area for authentication before updating the flash.
As for signal tap, you cannot use signal tap from the jtag header, you need use the remote signal tap method by establishing a port connection. https://www.intel.com/content/www/us/en/programmable/documentation/rjg1562957780901.html#ygy15711016...
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