SPRUIM2H May 2020 – October 2023 AM2431 , AM2432 , AM2434 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442
The XFRDMA block has a pair of PSI-L busses, one for transmit and one for receive. They are using the configured data width and number of threads. The transmit PSI-L is drived by the XOUT data, while the receive PSI-L will feed the XIN data and status. When there is a transmit word ready, the XFRDMA block will assert the thread_mready for that thread. The PSI-L arbiter will determine when a thread can transmit and only then will the XFRDMA actually transmit data. The XFRDMA block will assert the thread_sready to accept receive data when the buffer for that thread is able to accept another data phase. Again, the PSI-L arbiter will determine when a thread will receive data and only then will the buffer store the received data. Any PSI-L sideband signals are transmitted with the data phase, or received with the data phase.
The packet streaming interface (PSI) is used to transfer words of packet data and control information between two peer entities in the system via arbiter.
Figure 6-219 shows a block diagram of the PRU_ICSSG PSI topology.