SDAA515 August   2026 TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Detailed Description
    1. 2.1  DDR Inline ECC Overview
      1. 2.1.1 Benefits of DDR Inline ECC
    2. 2.2  ECC Protection Region Planning
    3. 2.3  ECC Capacity Considerations
    4. 2.4  ECC Configuration Guidelines
      1. 2.4.1 ECC Generation Phase
      2. 2.4.2 ECC Protection Phase
    5. 2.5  Why DDR Priming Is Required
    6. 2.6  DDR Priming Using DRU
    7. 2.7  DRU Resource Allocation
    8. 2.8  SBL Integration
    9. 2.9  Recommended Initialization Flow
    10. 2.10 Performance Evaluation
    11. 2.11 Troubleshooting Common DDR Inline ECC Deployment Issues
      1. 2.11.1 ECC Checking Enabled Before Priming
      2. 2.11.2 Incorrect ECC Region Configuration
      3. 2.11.3 Read-Modify-Write Disabled
    12. 2.12 Validation and Debug Considerations
  6. 3Summary
  7. 4References

2.5 Why DDR Priming Is Required

Following DDR initialization, memory contents are undefined.

Although memory locations can contain random data, valid ECC information does not yet exist for those locations.

If ECC checking is enabled immediately after DDR initialization, read operations to protected memory locations can trigger false ECC errors because valid ECC information has not yet been generated.

This behavior is often misinterpreted as a DDR hardware issue, when in fact the memory has simply not been initialized with valid ECC data.

DDR priming eliminates this condition by writing known data patterns across all ECC-protected memory locations. During these writes, the DDR controller automatically generates valid ECC information.