UNION DMUB_FW_META_FEATURE_BITS(9)

💅 union dmub_fw_meta_feature_bits(9) — from the Kernel API Manual, bestie

okay so picture this: you're deep in the kernel API manual, the section is literally called union dmub_fw_meta_feature_bits(9), and it's all about static feature bits for pre-initialization. That's the whole~vibe~. A little union holding a bundle of bitflags that get set up before the fancy init stuff happens. Pre-initialization era. Iconic.

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✨ NAME ✨

union dmub_fw_meta_feature_bits — static feature bits for pre-initialization. no cap, that's it, that's the name, and the description is right there in the title. main character entry honestly.

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🫶 SYNOPSIS 🫶

here's the whole shape of it, copied exactly so you can paste it into your notes and not get yelled at:

union dmub_fw_meta_feature_bits {
    struct {
      uint32_t shared_state_link_detection : 1;
      uint32_t cursor_offload_v1_support: 1;
      uint32_t inbox0_lock_support: 1;
      uint32_t reserved : 29;
    } bits;
    uint32_t all;
 };

so there's a nested struct called bits holding the actual one-bit fields (shared_state_link_detection, cursor_offload_v1_support, inbox0_lock_support, then reserved eating up the remaining 29 bits), and then a uint32_t all; so you can grab the whole 32-bit blob in one go. union life. you get to look at it bit-by-bit or all at once, and honestly? that's a serve. 💅

quick bit math for the girlies: three little 1-bit fields plus reserved : 29 = 32 bits total, which lines up perfectly with that uint32_t all;. the math is mathing. ✨

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🎀 Members 🎀

the Members section on this page is, um. empty. literally nothing listed under it — no bullet points, no one-liners, not a single crumb. 😭 so if you came here for a breakdown of each member, the answer is "look at the SYNOPSIS above, bestie, it's all up there." I'm not gonna invent lore that isn't in the source. we don't do that here. 🙈

so yeah: bits (the struct with the bitfields) and all (the uint32_t view of the whole thing). that's the tea the SYNOPSIS already spilled. 🍓

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🦋 SEE ALSO 🦋

okay this is the part where the page goes full group-chat-adds-everyone. the source lives in the kernel file ./drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h, and here's every single friend it tagged, in order, no crumbs left behind:

• union dmub_addr(9)
• struct dmub_cursor_offload_pipe_data_dcn30_v1(9)
• struct dmub_cursor_offload_pipe_data_dcn401_v1(9)
• struct dmub_cursor_offload_pipe_data_dcn60_v1(9)
• struct dmub_cursor_offload_pipe_data_v1(9)
• struct dmub_cursor_offload_payload_data_v1(9)
• struct dmub_cursor_offload_stream_v1(9)
• struct dmub_cursor_offload_v1(9)
• struct dmub_fw_meta_info(9)
• union dmub_fw_meta(9)
• struct dmcub_trace_buf_entry(9)
• union dmub_fw_boot_status(9)
• enum dmub_fw_boot_status_bit(9)
• enum dmub_cursor_offload_comand_type(9)
• union dmub_fw_boot_options(9)
• enum dmub_shared_state_feature_id(9)
• struct dmub_shared_state_ips_fw(9)
• struct dmub_shared_state_ips_driver(9)
• struct dmub_shared_state_cursor_offload_v1(9)
• struct dmub_shared_state_feature_block(9)
• union dmub_gpint_data_register(9)
• enum dmub_out_cmd_type(9)
• struct dmub_cmd_header(9)
• struct dmub_rb_cmd_common(9)
• struct dmub_cmd_PLAT_54186_wa(9)
• struct dmub_rb_cmd_PLAT_54186_wa(9)
• enum dmub_cmd_mall_type(9)
• struct dmub_rb_cmd_mall(9)
• enum dmub_cmd_cab_type(9)
• struct dmub_rb_cmd_cab_for_ss(9)
• enum dmub_fams2_allow_delay_check_mode(9)
• enum dmub_cmd_idle_opt_type(9)
• struct dmub_rb_cmd_idle_opt_dcn_restore(9)
• struct dmub_dcn_notify_idle_cntl_data(9)
• struct dmub_rb_cmd_idle_opt_dcn_notify_idle(9)
• enum dmub_idle_opt_dc_power_state(9)
• struct dmub_idle_opt_set_dc_power_state_data(9)
• struct dmub_rb_cmd_idle_opt_set_dc_power_state(9)
• struct dmub_clocks(9)
• enum dmub_cmd_clk_mgr_type(9)
• struct dmub_rb_cmd_clk_mgr_notify_clocks(9)
• struct dmub_cmd_digx_encoder_control_data(9)
• struct dmub_rb_cmd_digx_encoder_control(9)
• struct dmub_cmd_set_pixel_clock_data(9)
• struct dmub_cmd_enable_disp_power_gating_data(9)
• struct dmub_rb_cmd_enable_disp_power_gating(9)
• struct dmub_dig_transmitter_control_data_v1_7(9)
• union dmub_cmd_dig1_transmitter_control_data(9)
• struct dmub_rb_cmd_dig1_transmitter_control(9)
• struct dmub_rb_cmd_domain_control_data(9)
• struct dmub_rb_cmd_domain_control(9)
• struct dmub_rb_cmd_dpphy_init(9)
• enum dp_aux_request_action(9)
• enum aux_return_code_type(9)
• enum aux_channel_type(9)
• struct aux_transaction_parameters(9)
• struct dmub_rb_cmd_hpd_sense_notify(9)
• enum dmub_phy_fsm_state(9)
• enum dmub_abm_ace_curve_type(9)
• enum dmub_abm_histogram_type(9)
• enum dmub_cmd_panel_cntl_type(9)
• struct dmub_cmd_panel_cntl_data(9)
• struct dmub_rb_cmd_panel_cntl(9)
• struct dmub_cmd_cable_id_input(9)
• struct dmub_cmd_cursor_offload_init_data(9)
• struct dmub_rb_cmd_cursor_offload_init(9)
• struct dmub_cmd_cursor_offload_stream_data(9)
• struct dmub_rb_cmd_cursor_offload_stream_cntl(9)
• union dmub_rb_cmd(9)
• union dmub_rb_out_cmd(9)
• struct dmub_rb_init_params(9)
• struct dmub_rb(9)

like I said. everyone. the whole dmub extended universe showed up to the function. 👑

ngl there's no signature to #include here — this page is describing a union from the kernel source, so treat the references above as the reading list, not a call to action. 🧚

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and that's the page!! 💖 source/version is ./drivers/gpu/drm/amd/display/..., dated October 2026, manual name union dmub_...feature_bits(9), from the Kernel API Manual — mwah, bye bestie, go read dmub_cmd.h 🦋⭐🎀