LPDDR4/4X protocol uses feedback on the DQ bits during CA Training and Write Leveling calibration stages so any pin swapping needs to be done and validated in the tools. Additionally the DQ mapping from the adaptive SoC to the LPDDR4/4X component channels needs to maintain an exact one-to-one mapping. For example, LPDDR4_DQ_A must be connected to DQ0 of Channel A of the LPDDR4 component, LPDDR4_DQ_A must be connected to DQ1 of Channel A, through LPDDR4_DQ_B that must be connected to DQ15 of Channel B of the LPDDR4 component. You are encouraged to try the Obtaining and Verifying Versal Adaptive SoC Memory Pinouts tutorial available on GitHub. This is a fast and effective way to quickly generate pinouts for Versal DDRMCs. All pins swaps must be captured in the design's XDC and validated before generating hardware. PCB level pin swaps not captured in the tools may lead to hardware failures if pin rules are not followed.
Each DDRMC has three XPIO Banks (known as a triplet) associated with it.
An XPIO Bank comprises twenty seven differential pin pairs (L0P/N to L26P/N). There are
nine Nibbles in a Bank and each Nibble has six pins. The package pin name
IO_NiPj_MxPy describes the fields listed below.
- Ni is the Nibble number within a Bank (where i = 0 to 8)
Pj is the pin number within the Nibble (where j = 0 to 5).
- Mx is the DDRMC triplet number (where x = 0 to (Total number of
DDRMCs – 1))
Py is the pin number within the triplet (where y = 0 to 161).
- MxP0 through MxP53 are pins in the first Bank of the triplet.
- MxP54 through MxP107 are pins in the second Bank of the triplet.
- MxP108 through MxP161 are pins in the third Bank of the triplet.
|Nibble#Pin# in package pin name
|First pin in first Bank of triplet maps to first pin of Nibble 0 Pin 0
|Last pin of Nibble 0 in this Bank
|First pin of Nibble 1 in this Bank
|Last pin of Nibble 1 in this Bank
|First pin of Nibble 2 in this Bank
|Last pin of Nibble 2 in this Bank
|First pin of Nibble 3 in this Bank
|Last pin of Nibble 3 in this Bank
|First pin of Nibble 4 in this Bank
|Last pin of Nibble 4 in this Bank
|First pin of Nibble 5 in this Bank
|Last pin of Nibble 5 in this Bank
|First pin of Nibble 6 in this Bank
|Last pin of Nibble 6 in this Bank
|First pin of Nibble 7 in this Bank
|Last pin of Nibble 7 in this Bank
|First pin of Nibble 8 in this Bank
|Last pin of Nibble 8 in this Bank, Last pin in first Bank of triplet