Length Granularity - 3.3 English

Versal ACAP CPM DMA and Bridge Mode for PCI Express Product Guide (PG347)

Document ID
PG347
Release Date
2022-11-02
Version
3.3 English
Table 1. Length Granularity
Interface Type Datapath Width Length Granularity Restriction
AXI4 MM 64, 128, 256, 512 None
AXI4-Stream 64, 128, 256, 512 None 1
AXI4 MM fixed address 64 Length[2:0] == 3’h0
AXI4 MM fixed address 128 Length[3:0] == 4’h0
AXI4 MM fixed address 256 Length[4:0] == 5’h0
AXI4 MM fixed address 512 Length[5:0] == 6'h0
  1. Each C2H descriptor must be sized as a multiple of 64 Bytes. However, there are no restrictions to the total number of Bytes in the actual C2H transfer.