What can cause a calibration failure on the odd numbered ranks of a multiple rank DDR3 or DDR4 interface ?

Description

If you observe a calibration failure on only the odd numbered ranks of a DDR3 or DDR4 interface, this may be due to address mirroring not being enabled in the external memory interface IP parameters.

Resolution

Multiple rank DIMMs often use a feature known as address mirroring on the odd numbered ranks to optimize the PCB layout of the address signals.

Check your DIMM datasheet or contact the DIMM manufacturer to find out if the DIMM PCB layout uses address mirroring and set the IP parameter correctly.

• Arria® 10 External Memory Interfaces IP and Stratix® 10 External Memory Interfaces IP :   Memory tab > Topology > Enable address mirroring for odd ranks
• DDR3 SDRAM Controller with UniPHY : Memory Parameters tab > Memory Initialization Options > Mirror Addressing: 1 per chip select