3. Register Map and Address Spaces
The DMA AFU supports two memory views: The DMA view and the host view.
The DMA view supports a 49-bit address space. The lower half of the DMA view maps to the local FPGA memory. The upper half of the DMA view maps to host memory.
The host view includes all the registers accessible through MMIO accesses such as the DFH tables, and the control/status registers of the various IP cores used inside the DMA AFU.
The MMIO registers in the DMA BBB and AFU support 32- and 64- bit access. The DMA AFU does not support 512-bit MMIO accesses. Accesses to the Dispatcher registers inside the DMA BBB must be 32 bits (Descriptor frontend implements 64-bit registers).