The following data uniquely identifies each EEMI API call:
- EEMI API identifier (ID)
- EEMI API arguments
See OS and Libraries Document Collection (UG643) for a list of all API identifiers as well as API argument values.
Before initiating an IPI to the PMC, the PU writes the information about the call into the IPI request buffer. Each data written into the IPI buffer is a 32-bit word. Total size of the payload is six 32-bit words—one word is reserved for the EEMI API identifier, while the remaining words are used for the arguments. Writing to the IPI buffer starts from offset zero. The information is mapped as follows:
- Word  EEMI API ID
- Word [1:5] EEMI API arguments
The IPI response buffer is used to return the status of the operation as well as up to three values.
- Word  success or error code
- Word [1:3] value 1..3