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Zynq-7000 AP SoC Technical Reference Manual www.xilinx.com 264
UG585 (v1.11) September 27, 2016
Chapter 9: DMA Controller
Map PL Peripheral Interface to a DMA Channel
The DMAC enables software to assign a PL peripheral request interface to any of the DMA channels.
When a DMA channel thread executes DMAWFP, the value programmed in the PL peripheral [4:0]
field specifies the PL peripheral associated with that DMA channel. Refer to the DMAWFP instruction
in Table 9-8, page 272.
PL Peripheral Request Interface Timing Diagram
Figure 9-5 shows an example of the functional operation of the PL peripheral request interface using
the rules that handshake rules described, when a PL peripheral requests an AXI burst transaction.
State transitions in Figure 9-5:
T1 The DMAC detects a request for an AXI burst transaction.
Between T2 and T7 The DMAC performs the AXI burst transaction.
3
DMA{3:0}_DRLAST can only change when either:
DMA{3:0}_DRREADY is High
DMA{3:0}_DRVALID is Low
4
DMA{3:0}_DAVALID 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}_DAREADY is High
5
DMA{3:0}_DATYPE can only change when either:
DMA{3:0}_DAREADY is High
DMA{3:0}_DAVALID is Low
Notes:
1. All signals are synchronous to the DMA{3:0}_ACLK clock.
X-Ref Target - Figure 9-5
Figure 9-5: DMAC PL Peripheral Request Interface Burst Request Signaling
Table 9-1: DMAC PL Peripheral Request Interface Handshake Rules (Cont’d)
Rule Description
(1)
T0
Burst
Ack
AXI Data Burst
DMA Activity on the
AXI Data Bus
UG585_c9_06_030712
DMA{3:0}_ACLK
DMA{3:0}_DRVALID
DMA{3:0}_DRTYPE[1:0]
DMA{3:0}_DRREADY
DMA{3:0}_DAVALID
DMA{3:0}_DATYPE[1:0]
DMA{3:0}_DAREADY
T1 T2 T3 T4 T5 T6 T7 T8 T9