Intermittent DDR4 calibration failures

Dear PFern11,

The intermittent failures could be due to parameters setting. I suggest you to generate a DDR4 example design then compare your design with their example design (especially all DDR4 IP parameters setting) and see if any different that will causing this problem.

And one more thing, if this is on your custom board please make sure you have the RZQ resistor connect on board.

Also, here is the checklist that you can refer to:

https://www.intel.com/content/www/us/en/programmable/support/support-resources/support-centers/devices/cfg-index/calibration-checklist.html