Systems and methods for secure delivery of output surface bitmaps to a display engine. An example processing system comprises: an architecturally protected memory; and a plurality of processing devices communicatively coupled to the architecturally protected memory, each processing device comprising a first processing logic to implement an architecturally-protected execution environment by performing at least one of: executing instructions residing in the architecturally protected memory, or preventing an unauthorized access to the architecturally protected memory; wherein each processing device further comprises a second processing logic to establish a secure communication channel with a second processing device of the processing system, employ the secure communication channel to synchronize a platform identity key representing the processing system, and transmit a platform manifest comprising the platform identity key to a certification system.