From: Alex Hung <[email protected]> [WHAT] Add KUnit test coverage for needs_dsc_aux_workaround() in amdgpu_dm_mst_types.c. Tests verify the function correctly identifies links requiring the DSC AUX workaround based on branch device ID, DPCD revision, and sink count.
Assisted-by: Copilot:Claude-Opus-4.6 Reviewed-by: Bhawanpreet Lakha <[email protected]> Signed-off-by: Alex Hung <[email protected]> Signed-off-by: Aurabindo Pillai <[email protected]> --- .../display/amdgpu_dm/amdgpu_dm_mst_types.c | 2 + .../display/amdgpu_dm/amdgpu_dm_mst_types.h | 6 + .../drm/amd/display/amdgpu_dm/tests/Makefile | 1 + .../tests/amdgpu_dm_mst_types_test.c | 124 ++++++++++++++++++ 4 files changed, 133 insertions(+) create mode 100644 drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_mst_types_test.c diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c index 3b6433fb1345..9a70d1487b62 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c @@ -39,6 +39,7 @@ #include "dc.h" #include "dm_helpers.h" +#include "amdgpu_dm_kunit_helpers.h" #include "ddc_service_types.h" #include "dpcd_defs.h" @@ -248,6 +249,7 @@ bool needs_dsc_aux_workaround(struct dc_link *link) return false; } +EXPORT_IF_KUNIT(needs_dsc_aux_workaround); #if defined(CONFIG_DRM_AMD_DC_FP) static bool is_synaptics_cascaded_panamera(struct dc_link *link, struct drm_dp_mst_port *port) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h index 6f7ea684b555..5a7065e53645 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h @@ -57,8 +57,14 @@ enum mst_msg_ready_type { DOWN_OR_UP_MSG_RDY_EVENT = 3 }; +struct amdgpu_device; struct amdgpu_display_manager; struct amdgpu_dm_connector; +struct dc_state; +struct dc_stream_state; +struct dm_atomic_state; +struct drm_atomic_state; +struct drm_dp_mst_topology_mgr; uint32_t dm_mst_get_pbn_divider(struct dc_link *link); diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/Makefile b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/Makefile index ce1e46acb7af..fe9f32c9bdde 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/Makefile +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/Makefile @@ -17,3 +17,4 @@ obj-$(CONFIG_DRM_AMD_DC_KUNIT_TEST) += amdgpu_dm_psr_test.o obj-$(CONFIG_DRM_AMD_DC_KUNIT_TEST) += amdgpu_dm_replay_test.o obj-$(CONFIG_DRM_AMD_DC_KUNIT_TEST) += amdgpu_dm_ism_test.o obj-$(CONFIG_DRM_AMD_DC_KUNIT_TEST) += amdgpu_dm_wb_test.o +obj-$(CONFIG_DRM_AMD_DC_KUNIT_TEST) += amdgpu_dm_mst_types_test.o diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_mst_types_test.c b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_mst_types_test.c new file mode 100644 index 000000000000..e21386819ea1 --- /dev/null +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_mst_types_test.c @@ -0,0 +1,124 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT +/* + * KUnit tests for amdgpu_dm_mst_types.c + * + * Copyright 2026 Advanced Micro Devices, Inc. + */ + +#include <kunit/test.h> + +#include "dc.h" +#include "dpcd_defs.h" +#include "amdgpu_dm_mst_types.h" + +/* Tests for needs_dsc_aux_workaround */ + +/** + * dm_mst_test_needs_dsc_aux_workaround_match - Test workaround triggers for matching device + * @test: KUnit test context + * + * Verify that needs_dsc_aux_workaround() returns true when the link has + * the specific branch device ID, DPCD rev 1.4, and sink count >= 2. + */ +static void dm_mst_test_needs_dsc_aux_workaround_match(struct kunit *test) +{ + struct dc_link link = {0}; + + link.dpcd_caps.branch_dev_id = DP_BRANCH_DEVICE_ID_90CC24; + link.dpcd_caps.dpcd_rev.raw = DPCD_REV_14; + link.dpcd_caps.sink_count.bits.SINK_COUNT = 2; + + KUNIT_EXPECT_TRUE(test, needs_dsc_aux_workaround(&link)); +} + +/** + * dm_mst_test_needs_dsc_aux_workaround_rev12 - Test workaround triggers for DPCD rev 1.2 + * @test: KUnit test context + * + * Verify that needs_dsc_aux_workaround() returns true when the link has + * the specific branch device ID, DPCD rev 1.2, and sink count >= 2. + */ +static void dm_mst_test_needs_dsc_aux_workaround_rev12(struct kunit *test) +{ + struct dc_link link = {0}; + + link.dpcd_caps.branch_dev_id = DP_BRANCH_DEVICE_ID_90CC24; + link.dpcd_caps.dpcd_rev.raw = DPCD_REV_12; + link.dpcd_caps.sink_count.bits.SINK_COUNT = 3; + + KUNIT_EXPECT_TRUE(test, needs_dsc_aux_workaround(&link)); +} + +/** + * dm_mst_test_needs_dsc_aux_workaround_wrong_dev_id - Test workaround skipped for wrong device + * @test: KUnit test context + * + * Verify that needs_dsc_aux_workaround() returns false when the branch + * device ID does not match DP_BRANCH_DEVICE_ID_90CC24. + */ +static void dm_mst_test_needs_dsc_aux_workaround_wrong_dev_id(struct kunit *test) +{ + struct dc_link link = {0}; + + link.dpcd_caps.branch_dev_id = 0x123456; + link.dpcd_caps.dpcd_rev.raw = DPCD_REV_14; + link.dpcd_caps.sink_count.bits.SINK_COUNT = 2; + + KUNIT_EXPECT_FALSE(test, needs_dsc_aux_workaround(&link)); +} + +/** + * dm_mst_test_needs_dsc_aux_workaround_wrong_rev - Test workaround skipped for unsupported rev + * @test: KUnit test context + * + * Verify that needs_dsc_aux_workaround() returns false when the DPCD + * revision is neither 1.2 nor 1.4. + */ +static void dm_mst_test_needs_dsc_aux_workaround_wrong_rev(struct kunit *test) +{ + struct dc_link link = {0}; + + link.dpcd_caps.branch_dev_id = DP_BRANCH_DEVICE_ID_90CC24; + link.dpcd_caps.dpcd_rev.raw = 0x11; /* DPCD 1.1 */ + link.dpcd_caps.sink_count.bits.SINK_COUNT = 2; + + KUNIT_EXPECT_FALSE(test, needs_dsc_aux_workaround(&link)); +} + +/** + * dm_mst_test_needs_dsc_aux_workaround_low_sink_count - Test workaround skipped for single sink + * @test: KUnit test context + * + * Verify that needs_dsc_aux_workaround() returns false when the sink + * count is less than 2, even if device ID and DPCD rev match. + */ +static void dm_mst_test_needs_dsc_aux_workaround_low_sink_count(struct kunit *test) +{ + struct dc_link link = {0}; + + link.dpcd_caps.branch_dev_id = DP_BRANCH_DEVICE_ID_90CC24; + link.dpcd_caps.dpcd_rev.raw = DPCD_REV_14; + link.dpcd_caps.sink_count.bits.SINK_COUNT = 1; + + KUNIT_EXPECT_FALSE(test, needs_dsc_aux_workaround(&link)); +} + +static struct kunit_case dm_mst_types_test_cases[] = { + /* needs_dsc_aux_workaround tests */ + KUNIT_CASE(dm_mst_test_needs_dsc_aux_workaround_match), + KUNIT_CASE(dm_mst_test_needs_dsc_aux_workaround_rev12), + KUNIT_CASE(dm_mst_test_needs_dsc_aux_workaround_wrong_dev_id), + KUNIT_CASE(dm_mst_test_needs_dsc_aux_workaround_wrong_rev), + KUNIT_CASE(dm_mst_test_needs_dsc_aux_workaround_low_sink_count), + {} +}; + +static struct kunit_suite dm_mst_types_test_suite = { + .name = "amdgpu_dm_mst_types", + .test_cases = dm_mst_types_test_cases, +}; + +kunit_test_suite(dm_mst_types_test_suite); + +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_DESCRIPTION("KUnit tests for amdgpu_dm_mst_types"); -- 2.54.0
