Video BIOS Tables (VBT)

With the i915 driver probed, the VBT is available in Debugfs.

/sys/kernel/debug/dri/0/i915_vbt

The VBT contents may be decoded using the IGT tool intel_vbt_decode(1), but please always attach the binary file, not the decoded output to bugs.

The contents of the VBT are independent of the driver or kernel version. It may be different between UEFI and legacy boot; please prefer UEFI boot.

Alternative ways to get the VBT

ACPI OpRegion

For some systems, the VBT is also part of the ACPI OpRegion, available in Debugfs.

/sys/kernel/debug/dri/0/i915_opregion

Usually, where this works, the i915_vbt file also works.

intel_bios_dumper

intel_bios_dumper(1) is an IGT tool to save the entire Video BIOS to a file.

PCI ROM

You may also be able to dump the Video BIOS via the PCI ROM.

echo 1 > /sys/devices/pci0000:00/0000:00:02.0/rom
cat /sys/devices/pci0000:00/0000:00:02.0/rom > vbios.dump
echo 0 > /sys/devices/pci0000:00/0000:00:02.0/rom

Adjust the PCI device numbers as needed for your device.