External Memory Interfaces (EMIF) IP User Guide: Agilex™ 3 FPGAs and SoCs

ID 847458
Date 4/24/2025
Public
Document Table of Contents

3.3.1.5. Example: Byte Swizzling for 2 Channel x16 LPDDR4 Interface

Table 24.  Byte Swizzling for 2 Channel x16 LPDDR4 Interface
Lane Number BL0 BL1 BL2 BL3 BL4 BL5 BL6 BL7
Default placement wDQ[0] wDQ[1] wAC0 wAC[1] sAC0 sAC[1] sDQ[0] sDQ[1]
After Byte Swizzling wDQ[1] wDQ[0] wAC0 wAC[1] sAC0 sAC[1] sDQ[1] sDQ[0]
BYTE SWIZZLE_CH0 1 0 X X X X X X
BYTE SWIZZLE_CH1 X X X X X X 1 0

Channel 0 uses BL0 and BL1 as the DQ lanes, and BL2 and BL3 as AC lanes. Byte lane swapping between BL0,1 is allowed.

Channel 1 uses BL6 and BL7 as the DQ lanes, and BL4 and BL5 as AC lanes. Byte lane swapping between BL6,7 is allowed.

Cross-channel DQ lane swapping is not allowed.

Figure 15. Swizzling Channel 0 DQS Group 0 with DQS Group 1, and Channel 1 DQS Group 0 with DQS Group 1