SLUUDO2 September   2026 AM2611 , AM2612 , AM2612-Q1 , AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1 , AM263P2 , AM263P2-Q1 , AM263P4 , AM263P4-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Acronyms
  5. 2Introduction
  6. 3Introduction to CPSWSS and ENET-LLD
    1. 3.1 Hardware
    2. 3.2 Software
    3. 3.3 Application Software
      1. 3.3.1 Board and Peripherals Initialization (SYSCFG)
      2. 3.3.2 CPSW Configuration (ENET-LLD)
      3. 3.3.3 Operating System (FreeRTOS or NoRTOS)
      4. 3.3.4 Middleware Stack (LwIP, Arm® Mbed™ Platform TLS, TSN)
      5. 3.3.5 Application Layer
  7. 4Debugging Hardware and Software
    1. 4.1 Hardware Debugging
      1. 4.1.1 Schematic Review Checklist
        1. 4.1.1.1 Management Data Input/Output (MDIO and MDC)
        2. 4.1.1.2 RGMII Interface
      2. 4.1.2 PHY Debug
        1. 4.1.2.1 PHY Bootstrap Settings
        2. 4.1.2.2 Trace Length
        3. 4.1.2.3 Clock Configuration
        4. 4.1.2.4 Mode Settings
        5. 4.1.2.5 IO MUX and SW Switch Settings
        6. 4.1.2.6 PHY Troubleshooting Guides
        7. 4.1.2.7 Custom Pin MUX Settings
      3. 4.1.3 Test Setup
      4. 4.1.4 Software Debugging
        1. 4.1.4.1 Using GEL Scripts in CCS
          1. 4.1.4.1.1 Statistics Using GEL Scripts
          2. 4.1.4.1.2 Statistics Using Expressions
      5. 4.1.5 Debugging Custom Ethernet Software
        1. 4.1.5.1 Debugging Initialization Sequence
        2. 4.1.5.2 PHY Debugging
        3. 4.1.5.3 MAC Port Debugging
        4. 4.1.5.4 TX Path Debugging
        5. 4.1.5.5 Systematic Debugging Checklist
          1. 4.1.5.5.1 RX Path Debugging
          2. 4.1.5.5.2 Multicast or Broadcast Does Not Work, But Unicast Works
    2. 4.2 Custom Hardware Bring-Up Process
      1. 4.2.1 Example 1: CPSW PHY Loopback
        1. 4.2.1.1 Failure: PHY Not Detected or MDIO Bus Not Alive
        2. 4.2.1.2 Failure: TX Packets Transmitted But RX Count = 0
      2. 4.2.2 Example 2: CPSW MAC Loopback Example
        1. 4.2.2.1 Failure: MAC Loopback Initialization Fails
        2. 4.2.2.2 Failure: TX Packets Increase But RX = 0
        3. 4.2.2.3 Failure: Nonzero Error Counters
      3. 4.2.3 Example 3: Enet_Layer2_CPSW and Enet_Layer2_cpsw_switch
        1. 4.2.3.1 Hardware Setup
        2. 4.2.3.2 Failure: Link Never Comes UP
        3. 4.2.3.3 Failure: Link is Up But No Frames Are Received or Transmitted
        4. 4.2.3.4 Failure: RX and TX Counters Increase But Error Rates Are High
      4. 4.2.4 Example 4: Enet_lwip_cpsw_example
        1. 4.2.4.1 Failure: Link Never Comes Up
        2. 4.2.4.2 Failure: Links Up But No IP Address Is Assigned
        3. 4.2.4.3 Failure: Ping Fails Despite Link and IP Address
    3. 4.3 Debugging Packet Forwarding Issues (ALE and Statistics)
      1. 4.3.1 CPSW Statistics Architecture
        1. 4.3.1.1 What Each Block Measures
        2. 4.3.1.2 Counter Reference Tables
          1. 4.3.1.2.1 MAC Port – RX Counters
          2. 4.3.1.2.2 MAC Port – TX Counters
          3. 4.3.1.2.3 MAC Port and Host Port – ALE and FIFO Drop Counters
          4. 4.3.1.2.4 Host Port – ALE Flood and Overrun Counters
          5. 4.3.1.2.5 MAC Port RX Issues
          6. 4.3.1.2.6 MAC Port TX Issues
          7. 4.3.1.2.7 Host Port RX Issues
          8. 4.3.1.2.8 Host Port TX Issues
    4. 4.4 Custom Board Enablement in SYSCFG
    5. 4.5 LwIP Debug Guide
      1. 4.5.1 LwIP Stack Configuration
      2. 4.5.2 lwip_stats
  8. 5Conclusion
  9. 6References
4.3.1.2.4 Host Port – ALE Flood and Overrun Counters

These counters exist only in the host port block and reveal ALE flooding behavior.

Table 4-16 ALE Flood and Overrun Statistical Summary
Counter Struct Field What It Means
Unknown unicast count aleUnknownUcast Frames with a DA not found in ALE table – flooded to all ports
Unknown multicast count aleUnknownMcast Multicast DA not found in ALE table – flooded
Unknown broadcast count aleUnknownBcast Broadcast frames received – always flooded
TX SOF overrun txSofOverrun Start-of-frame DMA descriptor overrun on host port TX path
TX MOF overrun txMofOverrun Mid-of-frame DMA descriptor overrun on host port TX path