OpenTitan Pigweed target

Example project of the Pigweed kernel running on the OpenTitan Earl Grey chip.

Building

To build the IPC test, run:

.. code-block:: console

bazelisk build //target/earlgrey/ipc/user:ipc

Running

To run the IPC test, run

.. tab-set::

.. tab-item:: CW310
    .. code-block:: console

        bazelisk run //target/earlgrey/ipc/user:ipc_runner_hyper310

.. tab-item:: CW340
    .. code-block:: console

        bazelisk run //target/earlgrey/ipc/user:ipc_runner_hyper340

.. tab-item:: Verilator
    .. code-block:: console

        bazelisk run //target/earlgrey/ipc/user:ipc_runner_verilator

.. tab-item:: QEMU
    .. code-block:: console

        bazelisk run //target/earlgrey/tests/ipc/user:ipc_runner_qemu_test

Testing

To run the unittests, run

.. tab-set::

.. tab-item:: CW310
    .. code-block:: console

        bazelisk test --test_output=all --cache_test_results=no //target/earlgrey/unittest_runner:hyper310_test

.. tab-item:: CW340
    .. code-block:: console

        bazelisk test --test_output=all --cache_test_results=no //target/earlgrey/unittest_runner:hyper340_test

.. tab-item:: QEMU
    .. code-block:: console

        bazelisk test //target/earlgrey/tests/ipc/user:ipc_runner_qemu_test

    This test runs in approximately 2.6 seconds under QEMU.
    It is included in the ``earlgrey_qemu_tests`` workflow and runs on every PR via the ``ci`` group.

Adding a QEMU lane to a new earlgrey test

1. Confirm an existing verilator target — find the opentitan_test (or opentitan_runner) rule with interface = "verilator" in the target's BUILD.bazel.

2. Add a sibling QEMU test target in the same BUILD.bazel:

   .. code-block:: python

   opentitan_test(
       name = "<test>_qemu_test",
       interface = "qemu",
       tags = ["qemu"],
       target = ":<image_target>",
       timeout = "moderate",
   )
   

3. Omit ecdsa_key, spx_key, and nightly_test — those are not needed for QEMU tests.

4. No workflow wiring needed. The earlgrey_qemu_tests build uses --build_tag_filters=+qemu --test_tag_filters=+qemu and targets //target/earlgrey/..., so any opentitan_test target tagged qemu under target/earlgrey/ is automatically picked up and run on every PR via the ci group.

5. Canonical example: target/earlgrey/tests/ipc/user/BUILD.bazel — see the ipc_runner_qemu_test target.

VS Code setup

.. _rust-analyzer: https://rust-analyzer.github.io/

.. code-block:: console

bazelisk run @rules_rust//tools/rust_analyzer:gen_rust_project -- //target/...