During initialization and calibration, I see refreshes are applied only to one rank of a multi-rank DIMM. Is this a problem? How do I resolve this issue?
Refreshes not occurring during the calibration should not affect most designs. This becomes an issue only in the unlikely condition where data is meant to be kept after a memory/system reset condition, as the memory locations will not be refreshed as often as memory specification requires. However, this use case is not typically used since refreshes are not performed during the time the memory controller is in a reset condition anyway.
Currently, no work-around is available.
This issue is planned to be fixed in the latest MPMC memory controller starting in EDK 10.1, Service Pack 1.