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AR# 56713

Vivado Simulation - How do I compile libraries and perform simulation in Vivado using IUS (NCSim)


In Vivado Design Suite, the simulation libraries and models have changed from ISE.
How do I perform simulation using IUS (NCSim) in Vivado tools?



IUS (NCSim) provides two methods of referencing Xilinx model libraries for Functional and Gate Level Simulation: Precompiled and Dynamic.


The method of library reference in Vivado has changed from ISE.

The changes of note are:
  • The UNISIM library now contains both functional and timing simulation models.
  • A parameter xil_timing now indicates whether UNISIM models are functional or timing.
  • A retarget library has been included for legacy device functional and timing simulation component models.
  • XilinxCoreLib is not required for Vivado simulation. It can be included if an ISE based legacy IP is present.
  • The AXI BFM is license based, and requires a separate compilation step if licensed and used in the design.
  • The Vivado physical library directory path has changed from the ISE location (Logical Libraries are the same)

For more information, see Vivado Design Suite User Guide Logic Simulation (UG900).

Dynamic Library Compilation for Verilog Functional Simulation

Functional Simulation Command using IUS (NCSim)

irun -loadvpi $XILINX_VIVADO/ids_lite/ISE/lib/lin64/libxil_ncsim.so:xilinx_register_systf.xilinx_register_systf +access+rw -64bit
     -f $XILINX_VIVADO/data/secureip/secureip_cell.list.f               \
     -f $XILINX_VIVADO/data/secureip/axi_bfm/axi_bfm_cell.list.f        \
     -y $XILINX_VIVADO/data/verilog/src/unisims +libext+.v              \
     -y $XILINX_VIVADO/data/verilog/src/unimacro +libext+.v             \
     -y $XILINX_VIVADO/data/verilog/src/retarget +libext+.v             \
     -f customer_file_list.f $XILINX_VIVADO/data/verilog/src/glbl.v

IUS (NCSim) Option Notes:   
-loadvpi <file>         : load the licensing library for simulation (AXI BFM)
-y                      : include subdirectories
-f                      : include file list

Library Notes:
unisims                 : Xilinx primitive functional models
unimacro                : Macros models for large scale primitives
retarget                : unisim/simprim retarget library for older architectures
XilinxCoreLib           : ISE legacy IP models
secureip_cell.list      : List of secure IP components for inclusion
axi_bfm_cell.list       : Optional Encrypted AXI BFM model (requires license)
customer_file_list.f    : A customer file list constraining the file names to be simulated
Dynamic Library Compilation for Verilog Timing Simulation

Timing simulation is a three step process consisting of:
  1. Generating the simulation netlist (timesim.v generation)
  2. Annotating timing information to the netlist (SDF file generation)
  3. Analyzing, elaborating, and simulating the timing netlist and SDF using IUS (NCSim)

Timing Netlist/SDF Generation in Vivado:

write_verilog -mode timesim -sdf_file <sdf_file>.sdf <sim_netlist>.v
write_sdf <sdf_file>.sdf

Timing Simulation Command in IUS (NCSim)
irun -sdf_file <sdf_file>.sdf -y  $XILINX_VIVADO/data/verilog/src/unisims    \
     $XILINX_VIVADO/data/verilog/glbl.v                                      \
     -f $XILINX_VIVADO/data/secureip/secureip_cell.list.f                    \
     <testfixture>.v <sim_netlist>.v

IUS (NCSim) Option Notes:   
    -y          : include library subdirectories
    -f          : include file list

Library Notes:

unisims     : Xilinx primitive functional/timing models

Linked Answer Records

Master Answer Records

Answer Number Answer Title Version Found Version Resolved
58890 Xilinx Simulation Solution Center - Design Assistant - Third Party Simulators - Cadence IES N/A N/A

Associated Answer Records

Answer Number Answer Title Version Found Version Resolved
60154 2014.1 Install - XILINX_VIVADO and LD_LIBRARY_PATH environment variables are not set in settings64.bat/sh files N/A N/A
AR# 56713
Date Created 07/09/2013
Last Updated 04/15/2015
Status Active
Type General Article
  • Vivado Design Suite