As part of the HDMI 2.1 RX Subsystem, the AMD LogiCORE IP High-bandwidth Digital Content Protection (HDCP) receivers are designed to receive audiovisual content securely between two devices that are HDCP capable. In this HDMI 2.1 RX Subsystem, both HDCP 1.4 and HDCP 2.3 receiver IP cores are included and can be enabled by the HDCP option in the Vivado IDE.
As a guideline, HDCP 2.3 is used to decrypt all protected content in FRL mode. In TMDS mode, HDCP 2.3 is used to decrypt content at Ultra-High Definition (UHD) while HDCP 1.4 is the legacy content protection scheme used at lower resolutions to be backward compatible with HDCP 1.4 only sinks.
The following figure shows a configuration of the HDMI RX where both HDCP 1.4 and 2.3 are enabled. With both HDCP protocols enabled, the HDMI Subsystem configures itself in the cascade topology where the HDCP 1.4 and HDCP 2.3 are connected back-to-back. The HDCP Egress interface of the HDMI receiver sends encrypted audiovisual data, which is decrypted by the active HDCP block and sent back into the HDMI receiver over the HDCP Ingress interface to send to other video processing modules in the system through AXI4-Stream Video interface.
For more details on HDCP, see the HDCP 1.x Product Guide (PG224) and the HDCP 2.2 LogiCORE IP Product Guide (PG249).