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
4.3.1.2.8 Host Port TX Issues

Frames submitted by the CPU DMA to the CPSW. txGoodFrames increments when a frame exits the host port into the ALE. The ALE then forwards the frame toward MAC port 1 where macPort.txGoodFrames is meant to match.

Table 4-20 Host Port TX Statistical Summary
Scenario Nonzero Counter Root Cause Debug Method Fix | Reference
hostPort.txGoodFrames = 0; application confirms frames were sent N/A The DMA TX ring is not draining; frames are stuck in ring. Verify the return code of the EnetDma_submitTxPktQ() function. Check the TX confirmation callback is called. DMA or Packet Flow Debug
hostPort.txGoodFrames non-zero; macPort.txGoodFrames = 0; no collision hostPort.aleBlockDrop The state of the host port (port 0) ALE is not FORWARD. Issue CPSW_ALE_IOCTL_GET_PORT_STATE for port 0. Set port 0 to FORWARD: CPSW_ALE_IOCTL_SET_PORT_STATE.
Host TX OK; MAC TX zero; no aleBlockDrop hostPort.portMaskDrop The ALE DA lookup excluded MAC port 1 from the egress portmask. Inspect the DA entry portmask in the ALE table dump. Re-add the DA entry pointing to MAC port 1: CPSW_ALE_IOCTL_ADD_UCAST.
Host TX OK; tagged frames not reaching wire hostPort.aleVidIngressDrop The VLAN tag on the TX frame is not registered for the host port in the ALE. Dump the ALE VLAN entries. Check host port membership. Add the VLAN entry with the host port in the member list.
TX count correct but lower than submitted hostPort.txSofOverrun or txMofOverrun DMA TX descriptor ring overrun; the CPU is submitting faster than switch drains. Compare the TX submit rate versus macPort.txGoodFrames delta. Increase numTxPkts in the EnetDma_openTxCh() function. Check the TX confirmation task priority.