SPRUJB3 March 2024 AM67 , AM67A , TDA4AEN-Q1 , TDA4VEN-Q1
A thread is a complete flow-controlled stream of communication. The PSI-L thread space is divided into a 32K contiguous region representing all of the source threads (0x0000 - 0x7FFF) and a 32K contiguous region representing all of the destination threads (0x8000 - 0x8FFF).
Source threads are responsible for sending request transactions, accepting response transactions, and sending data transfer transactions. Destination threads are responsible for accepting request transactions, sending response transactions, and accepting data transfer transactions. A given thread generally performs only a single class of transactions (see PSI-L Defined Threads). Both source and destination threads may act as initiators for transfers on one of the PSI-L write sub-interfaces but in this case source threads are actually initiating data transfers while destination threads are only responding to a previous request issued by a source request. Source threads only transfer to destination threads and destination threads only transfer to source threads. Transfers between same thread types do not occur.
The following types of message transfers always originate from source threads and terminate in destination threads:
Configuration write message
Configuration read message
QM push message
QM pop message
QM divert message
Direct read operation message
Direct write operation message
DMA transfer request message
DMA data message
The following types of message transfers always originate in destination threads and terminate in source threads:
Configuration write response message
Configuration read response message
QM push response message
QM pop response message
QM divert response message
DMA transfer response message