There is no specific wiring recommendation. It is possible to terminate the wiring on the memory side before branching and then branch and provide equal-length wiring to each chip, or it is possible to terminate the wiring for each memory after branching.
However, whichever wiring method is selected, board simulation must be performed to confirm that there are no problems.
Please refer to the External Memory Interface (EMIF) Handbook below for trace lengths.
External Memory Interface Handbook Volume 2: Design Guidelines For UniPHY-based Device Families
Layout Guidelines for DDR2 SDRAM Interface
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Category: External Memory Interface
Tools:-
Device: Cyclone® V