Agilex™ 7 F-Series and I-Series FPGA Memory Subsystem IP User Guide

ID 789389
Date 7/15/2024
Public
Document Table of Contents

3.2. Memory Subsystem Lookup Core IPs

Lookup IP is also called content addressable memory (CAM); it is an associative array data structure that provides a result value based on an applied key value, and supports high-lookup-rate through an AXI-streaming interface, up to single-cycle lookup completion.

CAMs compare an input key value to a previous table of data and if the key value matches previously stored key values, returns the address location of the matched data. The memory subsystem IP currently supports three types of CAMs: binary CAM (BCAM) for on-chip exact matching, multi-bin lookup (MBL) for off-chip exact matching, and ternary CAM (TCAM) for wildcard matching. The following table summarizes the differences between the types.

Table 4.  Lookup Core IP Features
  Binary CAM (BCAM) Ternary CAM (TCAM) Multi-Bin Lookup (MBL)
Interfaces AXI - Stream, AXI-Lite AXI - Stream, AXI-Lite AXI- Stream, AXI-Lite
Memory On-chip On-chip External
Lookup Algorithm Exact match, Cuckoo filter algorithm Ternary match, Multi-slice ternary CAM Exact match Multi-Bin lookup
Flexibility Key width up to 512 bit, entries up to 4196 Key width up to 512 bit, entries up to 4096 Key width up to 1024 bits. Number of entries depends on external memory capacity.
Management Operations Lookup, insert, delete, modify, flush Lookup, insert, delete, flush Lookup, insert, delete, modify, flush