2.7.3 Initialization and Bring-Up of the DDR Subsystem

The DDR subsystem initializes in the following sequence:

1. DFI Initialization (DFI_INIT_START and DFI_INIT_COMPLETE)
2. DRAM Initialization
3. ZQCL
4. Write Leveling
5. DQS Gate Training
6. Read Data Eye Training
7. Write Calibration
8. Simple Burst Write
9. Simple Burst Read