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Registered: ‎06-05-2018

Simulation launched within Vivado using Questa does not find Unisim libs

I have a problem where when I simulate by launching a simulation from within Vivado 2018.2 using Questa 10.7c it does not know where the unisim libs are even though their path are in the modelsim.ini file. One of the vhdl files in the design calls uses the unisim lib:

library UNISIM;

I am using the Questa Advanced Simulator within Vivado and I have both verilog and vhdl modules.

I have included a file with the environment variables that are set in linux environment related to Questa and Vivado, the modelsim.ini file and compile.log and as you can see the unisim lib is down the path:

unisim = $XILINX_VIVADO_VSIM_LIB/unisim

But when the Questa compile is run I get this error within the compile log:

-- Compiling architecture STRUCTURE of AXM_A75_v1_0
** Error: ../../../../../../src/hdl/AXM_D01v1_0.vhd(3): (vcom-1598) Library "unisim" not found.
** Error: ../../../../../../src/hdl/AXM_D01v1_0.vhd(4): (vcom-1136) Unknown identifier "UNISIM".
** Note: ../../../../../../src/hdl/AXM_D01v1_0.vhd(6): VHDL Compiler exiting

So for some reason it does not know the unisim libs are in the location given in the modelsim.ini and yes I have verified that they are down that path.

One thing I did notice was that the simulation changes the date of the directories for the different libraries inside of the msim directory except for the unisim libs.


 The unisim libs are put there only if I do compile simulation libraries, if I don't do that the simulation step does not create them inside of the msim directory.

One more thing, if in the advanced tab of the tool setting for simulation in Vivado I don't enable incremental compilation then when I simulate it deletes the unisim lib directories which were put there by compile simulation library comamnd and does not re-create them.

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Registered: ‎09-15-2016

Hi @oscaro ,

Can you please try providing the absolute path in Modelsim.ini file for the libraries to check if the issue is from environment variable not being set or setup issue?

Also, can you please make sure that the Modelsim.ini file is in the same location where the simulator is being launched? Are you using custom scripts to launch simulation in Questasim? Can you please try using export_simulation command to generate the scripts for Questasim with -lib_map_path option pointing to the compiled libraries and then try running these generated scripts in Questasim standalone and check if you are still facing any issues?

Can you please share the compile_simlib.log file to check.

Thanks & Regards,
Sravanthi B
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