Simulator Integration

SystemVerilog (DPI)

Source

The PyHDL-IF SystemVerilog package must be compiled prior to compilation of code that uses PyHDL-IF artifacts. If you use a FuseSoC-based build system, simply place a dependency on fvutils::pyhdl-if.

If you directly specify sources:

  • Obtain the share directory by calling:

    % python3 -c 'import hdl_if; print(hdl_if.share())'
# OR
% python3 -m hdl_if share

  • Specify ${share}/dpi as an include directory

  • Specify ${share}/dpi/pyhdl_if.sv as a source file

DPI Shared Library

Two shared libraries must be specified as DPI libraries to the simulator:

  • PyHDL-IF entrypoint

  • Python

Obtain the paths to these libraries by running:

% python3 -c 'import hdl_if; print(" ".join(hdl_if.libs("dpi")))'
# OR
% python3 -m hdl_if libs --type dpi

Specify these as DPI libraries to your simulator using its preferred mechanism.

Verilog (VPI)

TBD

VHDL (VHPI)

TBD

VHDL (FLI)

TBD

Loading the Python Library

When the PyHDL-IF library is initialized, it will try to load the Python shared library and locate symbols for simulator-provided APIs.

By default, the following process is followed:

  • If ${LIBPYTHON_LOC} is set, this shared library is loaded and Python symbols are obtained from it.

  • Python symbols will be obtained from the simulator’s global namespace if Python symbols are available in the simulator’s global namespace.

  • Next, shared libraries loaded by the simulator process are checked to specified if they provide Python symbols.

  • Next, the available Python interpreter is used to discover where its shared library is installed.

LIBPYTHON_LOC

The environment variable LIBPYTHON_LOC can be set to specify the location of the Python shared library. Note that a full path must be specified.

PYHDL_IF_PYTHON

The environment variable PYHDL_IF_PYTHON can be set to specify the Python interpreter to probe for configuration information.