For the HDCP 1.4 TX, an HDCP Key Management module is needed, which can send keys over the AXI4-Stream interface to the HDCP 1.4 controller. The following figure shows an example of how the HDMI 2.1 TX Subsystem is connected to the HDCP Key Management module through a Key Management Bus (AXI4-Stream). The HDCP Key Management module is not part of the HDMI 2.1 TX Subsystem. For HDCP 1.4 design details, see the HDCP 1.x Product Guide (PG224).
However, the HDCP 2.3 key is handled slightly differently as it is solely controlled by the software application. The user application is responsible for providing the infrastructure to securely store and retrieve the keys to be loaded into the HDCP 2.3 drivers. For the detailed list of keys that are required to be loaded by the user application, see the HDCP 2.2 LogiCORE IP Product Guide (PG249).