If you were hoping at some point to see HDMI 2.1+ on Linux with AMD + Mesa, you're out of luck right now as it's simply not going to be happening.
There's been a bug report on the Mesa GitLab of "4k@120hz unavailable via HDMI 2.1" that's been open for a few years now, with lots of comments and chatter about the issue. The problem is that HDMI is a proprietary interface, whereas DisplayPort is run by the international non-profit VESA, so it's much more complicated for HDMI support.
In an update on the bug report, AMD engineer Alex Deucher commented: "The HDMI Forum has rejected our proposal unfortunately. At this time an open source HDMI 2.1 implementation is not possible without running afoul of the HDMI Forum requirements."
So if you're on Linux, it's going to continue to be best to buy hardware that uses DisplayPort.
On the NVIDIA side though, it seems like it may not be an issue, as developer Karol Herbst wrote on Mastodon: "Even though AMD might not be able to add support for HDMI 2.1, nouveau certainly will as Nvidia's open source driver _also_ supports HDMI 2.1 so there is no reason to believe that at least some drivers can't support HDMI 2.1
It's quite backwards, but apparently having all the logic inside firmware (like Nvidia does) will probably help us implementing support for HDMI 2.1"
So perhaps in future AMD may be able to do something similar with their firmware.
QuoteSo if you're on Linux, it's going to continue to be best to buy hardware that uses DisplayPort.I found that to be true regardless of Linux or AMD.
At least in my experience, I never had issues with DisplayPort, but definitely quite a few across platforms with HDMI.
Frustating to experience. Fun to watch.
In the end it again boils down to the DMCA's weird treatment of copy-protection.
If I had the money I would be looking at taking legal action. I am now 3k out of pocket thanks to the HDMI forum.
I use my TV for UHD4k Bluray and Gaming Consoles and all these require HDMI. This is why I chose HDMI for PC also. But now I am forced to buy a new display that used Display Port if I want to use all the HDMI 2.1 features I have already paid for.
I really wish HDMI would just Die. Sick of jumping through hoops.
Last edited by finaldest on 29 February 2024 at 3:19 pm UTC
Quoting: finaldestSo I have a fantastic 55 inch gaming capable TV which I paid over £2k for so I could have all the HDMI 2.1 features and £1k for a HDMI 2.1 capable GFX card but the HDMI forum wont allow me to use said hardware because they refuse to allow AMD to release drivers.
If I had the money I would be looking at taking legal action. I am now 3k out of pocket thanks to the HDMI forum.
I use my TV for UHD4k Bluray and Gaming Consoles and all these require HDMI. This is why I chose HDMI for PC also. But now I am forced to buy a new display that used Display Port if I want to use all the HDMI 2.1 features I have already paid for.
I really wish HDMI would just Die. Sick of jumping through hoops.
I think, and may be wrong, that this only applies to the open source AMD stack, the closed source driver may not be subject to this limitation.
Quoting: alka.setzerthis only applies to the open source AMD stack, the closed source driver may not be subject to this limitation.
Sure, but who wants to use the AMD closed source drivers? ATI/AMD has never been good at graphics drivers (on any OS).
Quoting: alka.setzerI think, and may be wrong, that this only applies to the open source AMD stack, the closed source driver may not be subject to this limitation.It does, unfortunately. Both mesa (gpu open drivers including amd's) and AMDGPU-PRO (amd's proprietary drivers) rely on the open source AMDGPU (part of the linux kernel), and this implementation was part of the kernel driver (and can't be anywhere but the kernel). So the HDMI forum rejecting this basically closed off hdmi 2.1 on amd for at least the existing gpus. It may yet be possible for next gpus to support hdmi 2.1 on linux by relying on a firmware level driver (like nvidia does) or on an internal chip that converts displayport signal to hdmi signal (like intel does).
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