9.6.2 Edge_Anchors for Memory Placement

The PolarFire silicon architecture requires that the Memory interface be placed in specific and pre-defined locations of the chip to achieve optimal QOR and timing performance. These specific location are called Edge_Anchors and are used to identify the specific location in the PolarFire chip for optimal Memory Interface I/O placement. See the PolarFire Family Memory Controller User Guide for a mapping of DDR memory interface types to Edge_Anchor locations. The Edge_Anchors are as follows:
  • NORTH_NE
  • NORTH_NW
  • SOUTH_SE
  • SOUTH_SW
  • WEST_NW
  • WEST_SW

The ports for each Edge_Anchor is represented by a different color for easy identification. The list of possible Edge_Anchors is context-sensitive to the Memory Interface type and represents the legal and optimal locations for the specific Memory interface type. The list of Edge_Anchors for DDR4, for example, is different from the list for DD2/DDR3. DDR4 has fewer locations (Edge_Anchors) for I/O placement than DDR2/DD3.