dm_test_crtc..._irq_dc_busy(9)

💅 dm_test_crtc..._irq_dc_busy(9) 💅

okay so bestie, welcome to the Kernel API Manual ✨ this is a lil page about one (1) KUnit test function in the amdgpu display crew, and honestly it's giving "small but important". let's get into it 🫶

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🌸 NAME 🌸

dm_test_crtc_set_vupdate_irq_dc_busy — the test that checks what happens to the vupdate irq when DC is like "no ty, request rejected" 🙅‍♀️

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✨ SYNOPSIS ✨

void dm_test_crtc_set_vupdate_irq_dc_busy (struct kunit *test );

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🎀 ARGUMENTS 🎀

• test — the KUnit test context 💖 that's the whole argument list, she's low maintenance

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🦋 DESCRIPTION 🦋

so picture this 👀 — you've got an OTG instance assigned, right? but there's no DC attached. in that exact situation, amdgpu_dm_irq_set returns false, and the function has to report the request as busy (-EBUSY). no cap, that's the whole vibe check this test is running 🔥

basically: no DC = not available = busy signal, and this test makes sure the code actually says so 💅

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💜 SEE ALSO 💜

the kernel file lives right here:

./drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_crtc_test.c

and here's the whole friend group 🫶 (yes, all of them, i'm not skipping a single one):

• dm_test_crtc_modeset_required_active_mode_changed(9)
• dm_test_crtc_modeset_required_active_active_changed(9)
• dm_test_crtc_modeset_required_active_connectors_changed(9)
• dm_test_crtc_modeset_required_inactive(9)
• dm_test_crtc_modeset_required_no_changes(9)
• dm_test_crtc_vrr_active_irq_variable(9)
• dm_test_crtc_vrr_active_irq_fixed(9)
• dm_test_crtc_vrr_active_irq_inactive(9)
• dm_test_crtc_vrr_active_irq_disabled(9)
• dm_test_crtc_vrr_active_irq_unsupported(9)
• dm_test_crtc_vrr_active_variable(9)
• dm_test_crtc_vrr_active_fixed(9)
• dm_test_crtc_vrr_active_inactive(9)
• dm_test_crtc_vrr_active_disabled(9)
• dm_test_crtc_vrr_active_unsupported(9)
• dm_test_crtc_is_headless_null_adev(9)
• dm_test_crtc_is_headless_no_connectors(9)
• dm_test_crtc_is_headless_writeback_only(9)
• dm_test_crtc_is_headless_disconnected_display(9)
• dm_test_crtc_is_headless_connected_display(9)
• dm_test_crtc_is_headless_mixed_connectors(9)
• dm_test_crtc_helper_mode_fixup_returns_true(9)
• dm_test_crtc_set_vupdate_irq_no_otg(9)
• dm_test_crtc_set_vupdate_irq_enable(9)
• dm_test_idle_create_workqueue(9)
• dm_test_idle_worker_disabled_clears_running(9)
• dm_test_idle_worker_enabled_breaks_when_idle_disallowed(9)
• dm_test_idle_worker_enabled_breaks_when_not_headless(9)
• dm_test_idle_worker_enabled_runs_body(9)
• dm_test_crtc_set_static_screen_optimze_no_sr_entry(9)
• dm_test_crtc_set_static_screen_optimze_sr_entry_psr(9)
• dm_test_crtc_set_static_screen_optimze_psr_su_skips(9)
• dm_test_crtc_enable_vblank_rejects_unconfigured(9)
• dm_test_crtc_enable_vblank_full_path(9)
• dm_test_crtc_enable_vblank_vupdate_busy(9)
• dm_test_crtc_enable_vblank_crtc_irq_error(9)
• dm_test_crtc_enable_vblank_in_reset(9)
• dm_test_crtc_enable_vblank_queues_work(9)
• dm_test_crtc_enable_vblank_ips_restore(9)
• dm_test_crtc_enable_vblank_ips_restore_replay(9)
• dm_test_crtc_update_active_planes_no_stream(9)
• dm_test_count_crtc_active_planes_none(9)
• dm_test_count_crtc_active_planes_mixed(9)
• dm_test_crtc_duplicate_state_copies_fields(9)
• dm_test_crtc_reset_state_allocates_state(9)
• dm_test_crtc_destroy_state_no_stream(9)
• dm_test_crtc_destroy_state_releases_stream(9)
• dm_test_crtc_handle_vblank_no_event(9)
• dm_test_crtc_handle_vblank_skips_when_flip_submitted(9)
• dm_test_crtc_handle_vblank_completes_cursor_only(9)
• dm_test_vblank_control_worker_setup(9)
• dm_test_vblank_control_worker_enable_increments(9)
• dm_test_vblank_control_worker_disable_decrements(9)
• dm_test_vblank_control_worker_disable_clamps_zero(9)
• dm_test_crtc_disable_vblank_no_irq_installed(9)
• dm_test_crtc_disable_vblank_vrr(9)
• dm_test_crtc_disable_vblank_queues_work(9)

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and that's the page, bestie 🎀 mwah 💋

source path: ./drivers/gpu/drm/amd/display/... · dated: October 2026 · dm_test_crtc..._irq_dc_busy(9) — go forth and test those irqs, ily 💖🌸