No 4K@120Hz and 5K@240Hz via HDMI 2.1 for Linux users with Radeon.
AMD has hit a snag in its efforts to enable HDMI 2.1+ functionality using its open-source Linux graphics driver. The HDMI Forum has officially rejected the chipmaker's proposal after the company faced the legal restrictions placed by the HDMI Forum's recent HDMI 2.1 Compliance Test Specification (CTS) update. In other words, the owners of high-end graphics cards won't see 4K at 120Hz or 5K at 240Hz via HDMI 2.1 until these features are integrated into a later version and AMD's driver supports the update.
AMD is suggesting a painless fix for Linux users, though. Simply move to DisplayPort if the HDMI 2.1 breakup is too much. They're clearly frustrated by this outcome. The chip designer saw its embedded HDMI 2.1 implementation as a "valuable opportunity" for open-source code. Instead, it was forced to tell Linux users to "move to DisplayPort" if they wanted the latest and greatest display tech. That's a decidedly less elegant solution, we'd say.
Regrettably, AMD Linux engineer Alex Deucher conveyed the setback, stating, "The HDMI Forum has regrettably rejected our proposal." This announcement was made in a formal statement within the bug report, with Deucher acknowledging the current infeasibility of an open-source HDMI 2.1 implementation within the confines of HDMI Forum requirements.
The issue dates back to a bug report filed in 2018, highlighting the lack of HDMI 2.1 support for 4K@120Hz and 5K@240Hz resolution modes in the open-source Linux drivers. This arose from a decision by the HDMI Forum in 2021 to limit access to its specifications. While it ensured the quality and validity of the HDMI experience, by only allowing authorized operators access to HDMI feature hardware technical details required to implement them, it also meant that developers whose technologies were used had to be compensated. This was not something within reach of open source driver support.
In response to this conundrum, AMD and the X.Org Foundation banded together to address the beef with the HDMI Forum. The trio got together and came up with a solution that'd allow a resolution that'd make it possible for an open-source interpretation of the now privatized HDMI specifications. For AMD's part, its Linux engineers along with the requisite legal folks spent months going down the list of HDMI features to see if exposing them to the open-source Radeon driver was possible. They eventually signed off on it and began cobbling together the internal code, and then waited for the HDMI Forum to give the effort its blessing. Unfortunately, the forum rejected the chipmaker's request for open-source driver support.
The rejection carries a heightened sense of frustration, particularly given the substantial investment of time and resources by AMD in engineering and prototyping HDMI 2.1+ features within its internal open-source AMDGPU codebase. This endeavor, designed to showcase the capabilities of HDMI 2.1+ for HDMI Forum review, now appears to have been a largely fruitless allocation of significant resources.
In the face of these barriers, AMD might have to resort to alternatives. That could involve adding extra features to its closed-source firmware, or using its "PSP" IP block to protect specific parts of HDMI's specification. The no-nonsense truth, however, remains the same: the open-source drivers won't support any HDMI 2.1+ features, so open-source aficionados are kindly asked to consider DisplayPort if they want the best experience.
Frequently Asked Questions (FAQs) - AMD's HDMI 2.1+ Implementation
How will this have an effect on proprietors of high-end pics cards?
Unfortunately, users with high-stop pix playing cards won't be able to enjoy features like 4K at 120Hz or 5K at 240Hz through HDMI 2.1 till these skills are incorporated into a later version, and AMD's driving force helps the update.
What answer does AMD recommend for Linux customers coping with this hassle?
AMD shows a trustworthy answer for Linux customers – make the transfer to DisplayPort if the disruptions because of HDMI 2.1 barriers turn out to be an excessive amount of to deal with.
How does AMD view the final results of this example?
AMD expresses clean frustration as their estimated "precious opportunity" for open-source code thru embedded HDMI 2.1 implementation did no longer come to fruition. Instead, Linux users are suggested to "move to DisplayPort" for the state-of-the-art in display generation.
What caused this problem in 2021?
In 2021, the HDMI Forum constrained public get admission to to its specifications, permitting simplest legal entities to get admission to technical info. While this move safeguards the pleasant of HDMI, it poses a challenge to open-source motive force guide due to compensation requirements for generation builders.
When become this problem first recognized?
The problem first got here to mild in 2018 when a bug file talked about the dearth of HDMI 2.1 assist for precise resolutions in open-source Linux drivers.