.. _coverage:

AVL-AXI Coverage
================

.. inheritance-diagram:: avl_axi._coverage
    :parts: 2


The :any:`Coverage <avl_axi._coverage.Coverage>` module is a passive component hangs of the :any:`ReadMonitor` and :any:`WriteMonitor` item_export.

Each :any:`SequenceItem` generated by the monitor is sampled against the coverage model defined in the :any:`Coverage <avl_axi._coverage.Coverage>` class.

The user can extend the coverage model by extending the :any:`__init__ <avl_axi._coverage.Coverage.__init__>` method.

.. code-block:: python

    avl.Factory.set_variable("*.agent_cfg.has_coverage", True)

Performance
-----------

AVL-AXI adds statistical coverage on all wait values (command, data and response), averaged over beats in order to provide a rough indication of performance.

Any cycle that valid is raised and ready is low in considered a wait cycles.

Users should also consider the :ref:`Bandwidth Monitor <bandwidth>` as a good guide of performance.