AMD developer Harry Wentland submitted a new patch series to the Linux kernel mailing list on May 1, 2026, targeting the amdgpu display driver. The patches bring HDMI Fixed Rate Link support, more commonly known as HDMI FRL, to AMD GPU users on Linux.
It is one of the most significant steps toward proper HDMI 2.1 support that Linux users have been waiting for years. This is not a finished product yet. But the direction is now clear.
HDMI FRL is the underlying transmission technology that makes HDMI 2.1’s headline capabilities possible. Without FRL, features like 4K at 144Hz, 8K at 60Hz, variable refresh rate over HDMI, and uncompressed high-bandwidth audio cannot be delivered through the connector.
Earlier HDMI versions used a different signaling scheme called TMDS, which caps out well below the bandwidth needed for these modern display modes. FRL replaces TMDS for high-speed HDMI 2.1 links, and its absence in the Linux amdgpu driver has been a longstanding gap.
Wentland credits two contributors by name in the patch series submission. Siqueira prepared the original work a couple of years ago while employed at AMD but was unable to get it submitted before leaving the company.
Jerry picked up that work afterward, hardened the codebase, and ran the compliance tests needed to bring the patches to a state suitable for kernel submission. The patch series has passed a representative subset of HDMI compliance testing.
A full compliance run is in progress, and the team does not expect it to surface any failures based on results from other test environments. Display Stream Compression support is deliberately absent from this patch series.
Wentland noted in his submission that DSC, the compression technology that allows HDMI 2.1 to carry very high resolution content at reduced bandwidth overhead, is still being tested and will arrive in a separate patch series later.
DSC support matters for scenarios like 4K at 240Hz or 8K over a single cable, where even FRL’s expanded bandwidth is not quite enough without compression. Its absence here does not block the initial FRL work from landing, but it does mean the full HDMI 2.1 feature set will come in stages rather than all at once.
AMD followed up the patch series with a statement on the Phoronix forums. A driver developer confirmed that a full HDMI 2.1 implementation will be available once all patches are ready and have completed compliance testing.
That statement, combined with the active patch submission, makes it realistic to expect proper HDMI 2.1 support for AMD GPU users on Linux to arrive during 2026. The backstory here involves the HDMI Forum, and it is worth understanding.
In February 2024, the HDMI Forum rejected an earlier open-source HDMI 2.1 implementation from AMD. The HDMI specification is proprietary. Unlike DisplayPort, which is administered by VESA as a more openly accessible standard, HDMI is controlled by a licensing body that has historically been hostile to open-source implementations.
Getting an open-source kernel driver to pass HDMI Forum compliance testing is a non-trivial legal and technical challenge, which is part of why progress on this has been slow. How AMD has navigated those licensing requirements with the current patch series is not yet fully clear, and it remains one of the more interesting open questions as the work moves toward a kernel merge.
For Linux desktop users, the practical significance of this work is straightforward. AMD GPU owners using HDMI connections to modern monitors and televisions have been limited to the capabilities of older HDMI versions when using the open-source amdgpu driver.
High refresh rates, wide color gamut at full resolution, and HDMI-based variable refresh rate have all required either DisplayPort or proprietary driver workarounds to access. If this patch series lands and the full implementation follows, those limitations go away. The open-source driver stack will finally be able to drive HDMI 2.1 connections to their full capability.
The patch series is currently under review on the amd-gfx mailing list. If it clears review without significant objections, it is a candidate for inclusion in the Linux 7.2 development cycle.
No kernel release target has been officially stated by AMD or the amdgpu maintainers. The full details of the patch submission are available on the Linux kernel mailing list archive.
