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Zynq-7000 AP SoC Technical Reference Manual www.xilinx.com 263
UG585 (v1.11) September 27, 2016
Chapter 9: DMA Controller
Both buses use the valid-ready handshake that the AXI protocol describes. For more information on
the handshake process, refer to the AMBA AXI Protocol v1.0 Specification.
The PL peripheral uses the DMA{3:0}_DRTYPE[1:0] registers to:
Request a single AXI transaction
Request a AXI burst transaction
Acknowledge a flush request
The DMAC uses the DMA{3:0}_DATYPE[1:0] registers to:
Signal when it completes the requested single AXI transaction
Signal when it completes the requested AXI burst transaction
Issue a flush request
The PL peripheral uses DMA{3:0}_DRLAST to:
Signal to the DMAC when the last data cycle of the AXI transaction commences
Handshake Rules
The DMAC uses the DMA handshake rules that Table 9-1 shows, when a DMA channel thread is
active, that is, not in the stopped state. Refer to the Figure 9-5, page 264 for more information.
X-Ref Target - Figure 9-4
Figure 9-4: DMAC PL Peripheral Request Interface Request/Acknowledge Signals
Table 9-1: DMAC PL Peripheral Request Interface Handshake Rules
Rule Description
(1)
1
DMA{3:0}_DRVALID can change from Low to High on any DMA{3:0}_ACLK cycle,
but must only change from High to Low when DMA{3:0}_DRREADY is High.
2
DMA{3:0}_DRTYPE can only change when either:
DMA{3:0}_DRREADY is High
DMA{3:0}_DRVALID is Low
DMA{3:0}_DRTYPE[1:0]
Peripheral
{3:0}
DMA{3:0}_DRLAST
DMA{3:0}_DATYPE[1:0]
DMA{3:0}_DAVALID
DMA{3:0}_DRREADY
DMA{3:0}_DAREADY
DMA{3:0}_DRVALID
DMAC
UG585_c9_05_030312
Peripheral
Request
Interface
{3:0}
DMA{3:0}_ACLK