rpmsg_lite_pingpong_tzm
Overview
The Multicore RPMsg-Lite pingpong TZM project is a simple demonstration program that uses the MCUXpresso SDK software and the RPMsg-Lite library and shows how to implement the inter-core communication between cores in the TrustZone-M (TZM) environment. The TZM is configured in the BOARD_InitTrustZone() function. The secondary core is put into the secure domain as well as the shared memory for RPMsg messages exchange. The primary core boots in the secure domain, it releases the secondary core from the reset and then the inter-core communication is established in the secure domain. Once the RPMsg is initialized and the secure endpoint is created the message exchange starts, incrementing a virtual counter that is part of the message payload. The message pingpong in the secure domain finishes when the counter reaches the value of 50. Then the secure domain is kept running and the non-secure portion of the application is started. The non-secure RPMsg-Lite endpoint is created in the non-secure domain and the new message pingpong is triggered, exchanging data between the secondary core secure endpoint and the primary core non-secure endpoint. Veneer functions defined in the secure project are called from the non-secure domain during this process. This message pingpong finishes when the counter reaches the value of 1050. Debug prints from the non-secure portion of the application are routed into the secure domain using the dedicated veneer function.