Better document level of simulator support
Add information about which simulators are known to be experimental.
@@ -7,6 +7,12 @@ Simulator Support
This page lists the simulators that cocotb can be used with
and documents specifics, limitations, workarounds etc.
+In general, cocotb can be used with any simulator supporting the industry-standard VPI, VHPI or FLI interfaces.
+However, in practice simulators exhibit small differences in behavior that cocotb mostly takes care of.
+
+If a simulator you would like to use with cocotb is not listed on this page
+open an issue at the `cocotb GitHub issue tracker <https://github.com/cocotb/cocotb/issues>`_.
+
.. _sim-icarus:
@@ -73,6 +79,13 @@ Issues for this simulator
Verilator
=========
+.. warning::
+
+ Verilator is in the process of adding more functionality to its VPI interface, which is used by cocotb to access the design.
+ Therefore, Verilator support in cocotb is currently experimental.
+ Some features of cocotb may not work correctly or at all.
+ It is highly recommended to use the latest version of Verilator.
+
In order to use this simulator, set :make:var:`SIM` to ``verilator``:
.. code-block:: bash
@@ -89,13 +102,9 @@ To run cocotb with Verilator, you need ``verilator`` in your PATH.
cocotb requires Verilator 4.106 or later.
-.. warning::
-
- Verilator support is currently experimental. Some features of cocotb may not work correctly or at all.
-
.. versionadded:: 1.3
-.. versionchanged:: 1.5 Improved cocotb support and greatly improved performance when using a higher time precision. Verilator 4.106 or later is required.
+.. versionchanged:: 1.5 Improved cocotb support and greatly improved performance when using a higher time precision.
Coverage
--------
@@ -225,8 +234,8 @@ Issues for this simulator
.. _sim-questa:
-Mentor Questa
-=============
+Mentor/Siemens EDA Questa
+=========================
In order to use this simulator, set :make:var:`SIM` to ``questa``:
@@ -242,12 +251,13 @@ Issues for this simulator
-------------------------
* `All issues with label category:simulators:questa <https://github.com/cocotb/cocotb/issues?q=is%3Aissue+-label%3Astatus%3Aduplicate+label%3Acategory%3Asimulators%3Aquesta>`_
-
+* Questa 2021.1 and later added experimental support the VHPI interface in addition to the proprietary FLI interface.
+ However, this support is not complete yet and users of cocotb should continue to use FLI for the time being.
.. _sim-modelsim:
-Mentor ModelSim
-===============
+Mentor/Siemens EDA ModelSim
+===========================
In order to use this simulator, set :make:var:`SIM` to ``modelsim``:
@@ -327,16 +337,17 @@ Issues for this simulator
GHDL
====
+.. warning::
+
+ GHDL support in cocotb is experimental.
+ Some features of cocotb may not work correctly or at all.
+
In order to use this simulator, set :make:var:`SIM` to ``ghdl``:
.. code-block:: bash
make SIM=ghdl
-.. warning::
-
- GHDL support is currently experimental. Some features of cocotb may not work correctly or at all.
-
Noteworthy is that despite GHDL being a VHDL simulator, it implements the :term:`VPI` interface.
.. _sim-ghdl-issues:
