AMDGPU Working On "Secure Display" Functionality
Over the past two years we have seen AMD Linux driver developers work on more "security" features that at least initially appeared to be driven by AMD picking up Chromebook design wins and needing to support this functionality for those use-cases. There has been HDCP display support for APUs to land as well as Trusted Memory Zones - TMZ for securing video memory buffers. The latest feature being tackled is "Secure Display TA".
The initial patches for Secure Display TA for the Linux kernel driver were published today. This Secure Display support appears to be for handling security-sensitive / trusted applications to ensure the display output isn't inadvertently read or modified by other (rogue) parties trying to snoop on the frame-buffer contents.
(Update: The feature has been summed up by one of the AMD Linux developers as for "detecting changes in a mission critical display.")
The Secure Display support ties into the PSP handling and does require microcode-level support. We'll see what use-cases ultimately come from this Secure Display TA support or which ISV has been pushing AMD to support it on Linux - this may very well be another case for Chromebook engineering requirements.
Should this "secure display" support be of something potentially interesting to you, the initial code can be found via these patches.