AMD has integrated HDMI 2.1 FRL support into its AMDGPU Linux 7.2 driver. This allows Radeon graphics cards to achieve higher resolutions and refresh rates, such as 4K at 120 Hz or 8K at 60 Hz, without relying on DisplayPort. The feature, however, will start disabled by default.
FRL active but without VRR until further notice 🎮
The implementation of FRL (Fixed Rate Link) is the key technical step to transmit video at high bit rates, surpassing the HDMI 2.0 limit. The driver recognizes link modes from 3 to 12 Gbps per lane. However, AMD has decided to start with the feature disabled until support for variable refresh rate (VRR) is complete, avoiding synchronization issues on compatible displays.
HDMI 2.1: the feature that arrives but doesn't turn on by itself 🔒
AMD gives us HDMI 2.1 on Linux, but with a condition: don't touch it until VRR is ready. It's like receiving a new car with the keys locked in a safe. Radeon users will have to wait a little longer to enjoy those smooth 120 Hz. At least, when it arrives, we'll know it works, even if it's through patches and patience.