OMAP3430
L3/L4 system
peripherals
Control
SDMA_IRQ_0
SDMA_IRQ_1
SDMA_IRQ_2
SDMA_IRQ_3
SDMA controller
Read port
S_DMA_[95:0]
MPU
INTC
M_IRQ_15
M_IRQ_14
M_IRQ_13
M_IRQ_12
L3/L4 system
peripherals
Companion
device
Write port
L4 interconnect
L4
peripherals
GPMC
interface
S_DMA_2
S_DMA_63
S_DMA_1
S_DMA_6
sys_ndmareq0
sys_ndmareq2
sys_ndmareq1
sys_ndmareq3
System interface pads
L4 interconnect
L3 interconnect
Device
dma-005
IVA2.2
INTC
EVT89
EVT90
Public Version
www.ti.com
SDMA Environment
Figure 11-2. External SDMA Requests Typical Application
An external device can use the external DMA request pins to start a logical channel transfer over the
general-purpose memory controller (GPMC) interface. The transfer can be a memory-to-memory transfer
in which the source memory is in the external device.
The external DMA request signals are not available on external pins by default after cold reset. See
, System Control Module, for instructions on multiplexing out the four signal lines to pins.
11.2.3 SDMA Request Scheme
The hardware DMA request line schemes can be either edge-sensitive, or transition-sensitive.
The sensitivity selection of the sys_ndmareq[3:0] lines can be configured in the system control module
through the following register bits:
•
CONTROL_DEVCONF0[0] SENSDMAREQ0 register bit for sys_ndmareq0
•
CONTROL_DEVCONF0[1] SENSDMAREQ1 register bit for sys_ndmareq1
•
CONTROL_DEVCONF1[7] SENSDMAREQ2 register bit for sys_ndmareq2
•
CONTROL_DEVCONF1[8] SENSDMAREQ3 register bit for sys_ndmareq3
The default scheme for the external DMA requests is transition-sensitive. Other DMA requests (coming
from device internal peripherals) are transition-sensitive, except display subsystem line trigger DMA
request (DSS_LINE_DMA), which is edge-sensitive.
shows the DMA request captured on a falling edge in the edge-sensitive scheme.
2339
SWPU177N – December 2009 – Revised November 2010
SDMA
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