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

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

6.2.4. TCAM Delete by Key Operations

This operation deletes an existing entry with a specified key, mask and entry ID. This operation is faster than deleting by entry, providing that at least some mask bits are set to 1.

To perform a delete operation, follow these steps in the AXI-Lite interface:

  1. Write the key to the key_n registers.
  2. Write the key to the mask_n registers.
  3. Write the result to the result_n registers.
  4. Write the entry ID to the entry register.
  5. Write the key to the mask_n registers, 0x4.
  6. Poll the mgmt_ctrl register until the busy bit = 0x0.
  7. Check the mgmt_ctrl success bit; a value of 0x1 indicates that the deletion has been completed.
Figure 27. Delete by Key Operation on TCAM

A successful deletion sets the mgmt_ctrl register success bit to 0x1; if the operation fails, mgmt_ctrl is set to 0x0. If you attempt to delete an entry that does not exist, the operation fails.

  • The address of mgmt_ctrl register is 0x20.
  • The address of key_n register is 0x1000.
  • The address of result_n register is 0x2000.
  • The address of mask_n register is 0x3000.
  • The address of entry register is 0x30.