SPRUIM2H May 2020 – October 2023 AM2431 , AM2432 , AM2434 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442
Entries can only be queued by SW onto the forward queue of a ring. To queue an entry the producer will write the entry contents (typically a pointer to the Packet Descriptor or a TR) to the memory location pointed to by the current write pointer and will decrement its internally maintained free entry occupancy. After the producer has confirmed that the data has actually landed it memory, it will then write to the forward doorbell register (RINGRT[a]_RT_FDB) for the ring to increment the pending forward occupancy count for the ring.
More than one entry can be queued with a single doorbell write as the entry count in the doorbell write indicates how many entries have been queued.