dm_test_dmu...nit_dmcu_abm(9)

🎀 dm_test_dmub_hw_init_dmcu_abm 🎀

okay so this is a page from the Kernel API Manual (yes, that manual, the big one 💅) and it's literally about one very specific KUnit test. she's niche, she's precise, she's everything. let's get into it bestie 🦋

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🌸 NAME 🌸

dm_test_dmub_hw_init_dmcu_abm — the test that checks hw init actually initializes DMCU and ABM when they're present 🫶

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✨ SYNOPSIS ✨

void dm_test_dmub_hw_init_dmcu_abm (struct kunit *test );

that's it. that's the whole signature. short king 👑

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💖 ARGUMENTS 💖

• test — the KUnit test context 🧪 she's the one holding the keys to the whole test, no cap

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🔥 DESCRIPTION 🔥

so here's the vibe: when the resource pool actually exposes a DMCU and an ABM (like, they're really there, not just a maybe), then dm_dmub_hw_init is supposed to do three things, bestie, and we're checking all three:

1. program the PSP version ⭐
2. invoke the DMCU init callback 🎀
3. record the running state that the DMCU reported 👑

three for three or it's not slaying, periodt 💅

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🦋 SEE ALSO 🦋

the whole friend group showed up for this one, and honestly? iconic 💜

Kernel file

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

the rest of the crew (all in section 9):

• dm_test_register_dmub_notify_callback_null_callback(9)
• dm_test_register_dmub_notify_callback_type_out_of_range(9)
• dm_test_register_dmub_notify_callback_valid(9)
• dm_test_register_dmub_notify_callback_offload_false(9)
• dm_test_dmub_aux_setconfig_callback_copies_and_completes(9)
• dm_test_dmub_aux_setconfig_callback_non_aux_no_complete(9)
• dm_test_dmub_aux_setconfig_callback_aux_with_null_dm_notify(9)
• dm_test_dmub_aux_setconfig_callback_set_config_reply(9)
• dm_test_dmub_aux_fused_io_callback_copies_reply_and_completes(9)
• dm_test_dmub_aux_fused_io_callback_max_ddc_line(9)
• dm_test_dmub_aux_fused_io_callback_null_args(9)
• dm_test_get_default_ips_mode_dcn35(9)
• dm_test_get_default_ips_mode_dcn351(9)
• dm_test_get_default_ips_mode_dcn36(9)
• dm_test_get_default_ips_mode_older_than_dcn35(9)
• dm_test_get_default_ips_mode_newer_default(9)
• dm_test_dmub_hw_init_no_dmub_srv(9)
• dm_test_dmub_hw_init_no_fb_info(9)
• dm_test_dmub_hw_init_no_firmware(9)
• dm_test_dmub_hw_init_success_fake_dmub(9)
• dm_test_dmub_hw_init_no_hw_support(9)
• dm_test_dmub_hw_init_bss_data(9)
• dm_test_dmub_hw_init_hw_init_fails(9)
• dm_test_dmub_hw_init_auto_load_timeout(9)
• dm_test_dmub_hw_init_apu_dpia_dcn35(9)
• dm_test_dmub_hw_init_sanity_checks_dcn31(9)
• dm_test_dmub_hw_init_sanity_checks_dcn314(9)
• dm_test_dmub_hw_resume_no_dmub_srv(9)
• dm_test_dmub_hw_resume_initialized_dmub(9)
• dm_test_dmub_hw_resume_full_init(9)
• dm_test_dmub_hw_resume_init_check_failed(9)
• dm_test_dmub_hw_resume_auto_load_timeout(9)
• dm_test_dmub_sw_init_unsupported_asic(9)
• dm_test_init_microcode_unsupported_asic(9)
• dm_test_dmub_get_vbios_bounding_box_default_null(9)
• dm_test_execute_dmub_cmd_null_dmub_srv(9)
• dm_test_process_dmub_aux_transfer_sync_engine_acquire(9)
• dm_test_process_dmub_aux_transfer_sync_protocol_error(9)
• dm_test_process_dmub_aux_transfer_sync_copies_data(9)
• dm_test_process_dmub_aux_transfer_sync_zero_length(9)
• dm_test_process_dmub_set_config_sync_unknown_error(9)
• dm_test_abort_fused_io_no_dmub_srv(9)

like I said. everyone was invited 🌈

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ngl this is a test page, so if you're here looking for runtime behaviour you're in the wrong group chat — this is about verifying that dm_dmub_hw_init does the right things in a test 💀

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okay that's the whole page, bestie, you ate that 🍓 mwah 💖

— with love from ./drivers/gpu/drm/amd/display/..., dated October 2026, signed dm_test_dmu...nit_dmcu_abm(9) 🧚‍♀️✨