intel_infoframes

intel_infoframes [OPTIONS]

-d <device>
    Specify the DRM device path to query, e.g., /dev/dri/card0.

-p <port_id>
    Filter by a specific DisplayPort connector ID (e.g., 0, 1) to show info frames only for that port.

-n <port_name>
    Filter by a specific DisplayPort connector name (e.g., DP-1) to show info frames only for that port.

-t <type>
    Filter by a specific info frame type (e.g., 'AVI', 'SPD', 'VSD') to display only frames of that kind.

-h
    Display help information and exit.

The intel_infoframes command is a specialized diagnostic utility used for debugging DisplayPort (DP) related issues on Intel i915 graphics hardware. It is part of the intel-gpu-tools suite, providing a mechanism to read and dump the contents of DP info frames.

Info frames are small packets of data transmitted over a DisplayPort link alongside the main video and audio streams. They carry crucial metadata about the display configuration, such as AVI (Auxiliary Video Information) frames for video parameters, SPD (Source Product Description) frames for source device capabilities, and VSD (Vendor Specific Data) frames for proprietary information.

This tool is particularly useful for identifying problems related to display mode setting, audio synchronization, or Multi-Stream Transport (MST) setups, where incorrect or missing info frames can lead to display detection failures or suboptimal performance. It typically interfaces with the kernel's debugfs to access raw info frame data from the i915 driver.

This command is specific to Intel i915 graphics hardware and requires the debugfs filesystem to be mounted (usually at /sys/kernel/debug).
It typically requires root privileges or membership in the appropriate system groups (e.g., video or render) to access DRM device files and debugfs entries.
The output is highly technical and requires knowledge of DisplayPort specifications and info frame structures to fully interpret.
Its availability depends on the installation of the intel-gpu-tools package, which is not always installed by default.

The output of intel_infoframes typically consists of a list of detected DisplayPort connectors and, for each, the raw hexadecimal dumps of various info frames received or transmitted. Each frame is usually prefixed with its type (e.g., AVI, SPD, VSD, MSA), version, length, and often a timestamp. Understanding this output requires familiarity with the DisplayPort standard's sections on info frame packets to decipher the meaning of individual bytes and bits, which encode details like pixel format, color space, audio channels, and vendor-specific data.

intel_infoframes is primarily used by system administrators, Linux kernel developers, and power users who are actively debugging intricate display problems on Intel platforms. This includes scenarios like monitors not being detected, incorrect display resolutions or refresh rates, audio over DP not working, or issues with multi-monitor setups utilizing MST. It provides low-level insights that general display tools like xrandr cannot.

The intel_infoframes tool emerged as part of the intel-gpu-tools project, a collection of utilities developed alongside the Linux kernel's i915 DRM driver. Its development is closely tied to the need for advanced debugging capabilities for Intel's integrated graphics, particularly as DisplayPort became a prevalent display interface and complex features like Multi-Stream Transport (MST) were introduced. It provides a user-space interface to expose kernel-level information about DP info frame reception and transmission, aiding driver developers and advanced users in diagnosing display connectivity and mode setting issues over the years.

modinfo i915(8), xrandr(1), journalctl(1), lspci(8), cat /sys/kernel/debug/dri/0/i915_info_frames(9)