VIDEO BIOS TABLE (VBT)(9)

💖 Video BIOS Table (VBT) 💖

okay so this is the Video BIOS Table (VBT)(9) page from the Kernel API Manual, and it’s genuinely giving “important little config queen.” The Video BIOS Table, or VBT, hands the driver platform- and board-specific configuration info that it literally cannot discover or get through other means. Most of that configuration is about display hardware, bestie. The VBT is available via the ACPI OpRegion or, on older systems, in the PCI ROM. no cap. ✨

The VBT is made of a VBT Header (defined as struct vbt_header), a BDB Header (struct bdb_header), and a number of BIOS Data Blocks (BDB) that contain the actual configuration information. The VBT Header — and therefore the VBT itself — begins with the "$VBT" signature. The VBT Header contains the offset of the BDB Header. The data blocks are concatenated after the BDB Header. Each data block has a 1-byte Block ID, a 2-byte Block Size, and Block Size bytes of data. (Block 53, the MIPI Sequence Block is an exception.) 👑

The driver parses the VBT during load. The relevant information is stored in driver private data for ease of use, and the actual VBT is not read after that. periodt. 💅

🦋 SEE ALSO 🦋

• Kernel file ./drivers/gpu/drm/i915/display/intel_bios.c
• intel_bios_is_valid_vbt(9)
• intel_bios_init(9)
• intel_bios_driver_remove(9)
• intel_bios_is_tv_present(9)
• intel_bios_is_lvds_present(9)
• intel_bios_is_port_present(9)
• intel_bios_is_dsi_present(9)

💌 final cute sign-off: source/version vibes are ./drivers/gpu/drm/i915/display, dated October 2026, and the page title Video BIOS Table (VBT)(9) is living its best life in the footer. mwah 💋✨