Intel Preparing HDMI 2.1 FRL For Their Linux Driver, Native HDMI 2.1 For Meteor Lake
Current Intel Arc Graphics (DG2/Alchemist) only natively support HDMI 2.0 but HDMI 2.1 can be an option with some of the cards where the board vendor chooses to use a PCON for converting a DisplayPort 2.0 output from the GPU to an HDMI 2.1 interface. But now for Meteor Lake integrated graphics (and presumably for DG3/Battlemage) there will be native HDMI 2.1.
Native HDMI 2.1 coming with Meteor Lake (MTL).
Sent out by Intel engineers today were a "request for comments" on wiring up the Intel i915 driver with HDMI 2.1 Fixed Rate Link (FRL) training support.HDMI 2.1 FRL allows re-purposing the TMDS clock channel to be used as an additional data channel/lane for supporting higher bit rates. HDMI 2.1 FRL allows for 48 Gbps bandwidth. HDMI FRL is necessary for higher uncompressed resolutions beyond 4K60 and more efficient compressed video transport. This FRL bring-up is part of the broader work on enabling Intel Meteor Lake's native HDMi 2.1 capabilities under Linux.
The Intel HDMI 2.1 FRL support is now out for review on their mailing list as they continue work on enabling Meteor Lake graphics support (and other new Meteor Lake CPU features) for their open-source Linux drivers well in advance of these processors shipping that succeed Raptor Lake.