Hi, This series introduce Kunit tests to the vc4 KMS driver, but unlike what we have been doing so far in KMS, it actually tests the atomic modesetting code. In order to do so, I've had to improve a fair bit on the Kunit helpers already found in the tree in order to register a full blown and somewhat functional KMS driver. It's of course relying on a mock so that we can test it anywhere. The mocking approach created a number of issues, the main one being that we need to create a decent mock in the first place, see patch 22. The basic idea is that I created some structures to provide a decent approximation of the actual hardware, and that would support both major architectures supported by vc4. This is of course meant to evolve over time and support more tests, but I've focused on testing the HVS FIFO assignment code which is fairly tricky (and the tests have actually revealed one more bug with our current implementation). I used to have a userspace implementation of those tests, where I would copy and paste the kernel code and run the tests on a regular basis. It's was obviously fairly suboptimal, so it seemed like the perfect testbed for that series. It can be run using: ./tools/testing/kunit/kunit.py run \ --kunitconfig=drivers/gpu/drm/vc4/tests/.kunitconfig \ --cross_compile aarch64-linux-gnu- --arch arm64 Let me know what you think, Maxime To: David Airlie <airlied@xxxxxxxxx> To: Daniel Vetter <daniel@xxxxxxxx> To: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> To: Maxime Ripard <mripard@xxxxxxxxxx> To: Thomas Zimmermann <tzimmermann@xxxxxxx> Cc: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx> Cc: Javier Martinez Canillas <javierm@xxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Maíra Canal <mairacanal@xxxxxxxxxx> Cc: Brendan Higgins <brendan.higgins@xxxxxxxxx> Cc: David Gow <davidgow@xxxxxxxxxx> Cc: linux-kselftest@xxxxxxxxxxxxxxx Cc: kunit-dev@xxxxxxxxxxxxxxxx Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: linux-media@xxxxxxxxxxxxxxx Cc: linaro-mm-sig@xxxxxxxxxxxxxxxx Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> --- Changes in v3: - Add a Kconfig option for the KUnit helpers - Switch to EXPORT_SYMBOL_GPL for the helpers - Add some documentation on how to run the tests - Add some documentation for __vc4_crtc_init - Fix KUnit casing - Link to v2: https://lore.kernel.org/r/20221123-rpi-kunit-tests-v2-0-efe5ed518b63@xxxxxxxxxx Changes in v2: - Added some documentation for public functions - Removed the fake device probe/remove workqueue - Made sure the tests could be compiled as modules - Moved the vc4 tests in the vc4 module - Applied some of the preliminary patches - Rebased on top of current drm-misc-next branch - Fixed checkpatch issues - Introduced BCM2835 (Pi0-3) tests for muxing - Introduced tests to cover past bugs we had - Link to v1: https://lore.kernel.org/r/20221123-rpi-kunit-tests-v1-0-051a0bb60a16@xxxxxxxxxx --- Maxime Ripard (20): drm/tests: helpers: Move the helper header to include/drm drm/tests: Introduce a config option for the KUnit helpers drm/tests: helpers: Document drm_kunit_device_init() drm/tests: helpers: Switch to EXPORT_SYMBOL_GPL drm/tests: helpers: Rename the device init helper drm/tests: helpers: Remove the name parameter drm/tests: helpers: Create the device in another function drm/tests: helpers: Switch to a platform_device drm/tests: helpers: Make sure the device is bound drm/tests: helpers: Allow for a custom device struct to be allocated drm/tests: helpers: Allow to pass a custom drm_driver drm/tests: Add a test for DRM managed actions drm/vc4: Move HVS state to main header drm/vc4: crtc: Introduce a lower-level crtc init helper drm/vc4: crtc: Make encoder lookup helper public drm/vc4: hvs: Provide a function to initialize the HVS structure drm/vc4: tests: Introduce a mocking infrastructure drm/vc4: tests: Fail the current test if we access a register drm/vc4: tests: Add unit test suite for the PV muxing Documentation: gpu: vc4: Add KUnit Tests Section Documentation/gpu/vc4.rst | 16 + drivers/gpu/drm/Kconfig | 7 + drivers/gpu/drm/Makefile | 2 +- drivers/gpu/drm/tests/Makefile | 5 +- drivers/gpu/drm/tests/drm_client_modeset_test.c | 19 +- drivers/gpu/drm/tests/drm_kunit_helpers.c | 106 ++- drivers/gpu/drm/tests/drm_kunit_helpers.h | 11 - drivers/gpu/drm/tests/drm_managed_test.c | 71 ++ drivers/gpu/drm/tests/drm_modes_test.c | 19 +- drivers/gpu/drm/tests/drm_probe_helper_test.c | 20 +- drivers/gpu/drm/vc4/Kconfig | 16 + drivers/gpu/drm/vc4/Makefile | 7 + drivers/gpu/drm/vc4/tests/.kunitconfig | 13 + drivers/gpu/drm/vc4/tests/vc4_mock.c | 200 +++++ drivers/gpu/drm/vc4/tests/vc4_mock.h | 63 ++ drivers/gpu/drm/vc4/tests/vc4_mock_crtc.c | 41 + drivers/gpu/drm/vc4/tests/vc4_mock_output.c | 138 +++ drivers/gpu/drm/vc4/tests/vc4_mock_plane.c | 47 + drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c | 1039 +++++++++++++++++++++++ drivers/gpu/drm/vc4/vc4_crtc.c | 120 ++- drivers/gpu/drm/vc4/vc4_dpi.c | 13 +- drivers/gpu/drm/vc4/vc4_drv.c | 4 +- drivers/gpu/drm/vc4/vc4_drv.h | 91 +- drivers/gpu/drm/vc4/vc4_dsi.c | 9 +- drivers/gpu/drm/vc4/vc4_hdmi_regs.h | 4 + drivers/gpu/drm/vc4/vc4_hvs.c | 81 +- drivers/gpu/drm/vc4/vc4_kms.c | 25 +- drivers/gpu/drm/vc4/vc4_txp.c | 15 +- drivers/gpu/drm/vc4/vc4_vec.c | 13 +- include/drm/drm_kunit_helpers.h | 91 ++ 30 files changed, 2132 insertions(+), 174 deletions(-) --- base-commit: 199557fab92548f8e9d5207e385097213abe0cab change-id: 20221123-rpi-kunit-tests-87a388492a73 Best regards, -- Maxime Ripard <maxime@xxxxxxxxxx>