AR# 46782

描述

Version Found: V1.4

Version Resolved: Xilinx Answer 45195

All of the MIG 7 Series designs have been tested with the default XST option. 

When "Keep Hierarchy" is set to YES, the following errors will be seen in MAP :

ERROR:MapLib:1121 - ddr2_ctrl_tl_i/mig_ddr2_wrapper_i/mig_ddr2_core_i/u_memc_ui_top_std/mem_intfc0/ddr_phy_top0/u_ddr_mc_phy_wrapper/gen_dqs_iobuf[0].gen_dqs_diff.u_iobuf_dqs/OBUFTDS is driven by ddr2_ctrl_tl_i/mig_ddr2_wrapper_i/mig_ddr2_core_i/u_memc_ui_top_std/mem_intfc 0/ddr_phy_top0/u_ddr_mc_phy_wrapper/u_ddr_mc_phy/ddr_phy_4lanes_0.ddr_phy_4la nes/ddr_byte_lane_B.ddr_byte_lane_B/ddr_byte_group_io/dqs_gen.oddr_dqs (Q pin) and ddr2_ctrl_tl_i/mig_ddr2_wrapper_i/mig_ddr2_core_i/u_memc_ui_top_std/mem_intfc0/ddr_phy_top0/u_ddr_mc_phy_wrapper/u_ddr_mc_phy/ddr_phy_4lanes_0.ddr_phy_4lanes/ddr_byte_lane_B.ddr_byte_lane_B/ddr_byte_group_io/dqs_gen.oddr_dqsts (Q pin),but they are not all in the same level of hierarchy. Please ensure that any OBUF(T)DS with differential IOSTANDARD that is driven by a register or OSERDES exists in the same level of hierarchy as its drivers. This may be achieved by setting KEEP_HIERARCHY=FALSE on those levels of hierarchy separating the OBUF(T)DS from its drivers.

解决方案

To work around this issue, set "Keep Hierarchy" to Soft or add keep_hierarchy constraints for all of the sub-modules of the MIG design.

This can be done in either the xcf or ucf file.