On Tue, 08 Dec 2020, Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx> wrote: > This patch series attempts to add support for a DP-HDMI2.1 Protocol > Convertor. The VESA spec for the HDMI2.1 PCON are proposed in Errata > E5 to DisplayPort_v2.0: > https://vesa.org/join-vesamemberships/member-downloads/?action=stamp&fileid=42299 > The details are mentioned in: > VESA DP-to-HDMI PCON Specification Standalone Document > https://groups.vesa.org/wg/DP/document/15651 > > This series starts with adding support for FRL (Fixed Rate Link) > Training between the PCON and HDMI2.1 sink. > As per HDMI2.1 specification, a new data-channel or lane is added in > FRL mode, by repurposing the TMDS clock Channel. Through FRL, higher > bit-rate can be supported, ie. up to 12 Gbps/lane (48 Gbps over 4 > lanes). > > With these patches, the HDMI2.1 PCON can be configured to achieve FRL > training based on the maximum FRL rate supported by the panel, source > and the PCON. > The approach is to add the support for FRL training between PCON and > HDMI2.1 sink and gradually add other blocks for supporting higher > resolutions and other HDMI2.1 features, that can be supported by pcon > for the sources that do not natively support HDMI2.1. > > This is done before the DP Link training between the source and PCON > is started. In case of FRL training is not achieved, the PCON will > work in the regular TMDS mode, without HDMI2.1 feature support. > Any interruption in FRL training between the PCON and HDMI2.1 sink is > notified through IRQ_HPD. On receiving the IRQ_HPD the concerned DPCD > registers are read and FRL training is re-attempted. > > Currently, we have tested the FRL training and are able to enable 4K > display with TGL Platform + Realtek PCON RTD2173 with HDMI2.1 supporting > panel. Per IRC chat with Maarten and Daniel, once all the reviews are in, I'll add a topic branch and apply the patches there, so we can merge the branch to both drm-misc-next and drm-intel-next. BR, Jani. -- Jani Nikula, Intel Open Source Graphics Center _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel