For an interrupt event, read both Interrupt Cause and Interrupt Cause 1 registers.
Important: The software is required to form
appropriate LINK_ADDRESS sideband reply as per the Message Transaction protocol given in
Section 2.11.2 of DisplayPort Standard v1.2a specification. The
LINK_ADDRESS reply helps the source to identify the topology of the sink. For example,
if the sink core is configured for 4 MST streams, it receives the multi-stream input
from the DisplayPort TX and outputs four individual streams in native video format. In
this case, the LINK_ADDRESS_REPLY can be modeled to contain 1 input and 4 output logical
ports, with their DisplayPort device plug status set as 1 and Peer Device Type set as
3.