
the estimated resource usage for a SG-DMA controller core used for memory to memory transfer. The
core is configurable and the resource utilization varies with the configuration specified.
Table 21-1: SG-DMA Estimated Resource Usage
Datapath Cyclone
®
II Stratix
®
(LEs)
Stratix II
(ALUTs)
8-bit datapath 850 650 600
32-bit datapath 1100 850 700
64-bit datapath 1250 1250 800
The core operating frequency varies with the device and the size of the datapath. The table below provides
an example of expected performance for SG-DMA cores instantiated in several different device families.
Table 21-2: SG-DMA Peak Performance
Device Datapath f
MAX
Throughput
Cyclone II 64 bits 150 MHz 9.6 Gbps
Cyclone III 64 bits 160 MHz 10.2 Gbps
Stratix II/Stratix II
GX
64 bits 250 MHz 16.0 Gbps
Stratix III 64 bits 300 MHz 19.2 Gbps
Functional Description
The SG-DMA controller core comprises three major blocks: descriptor processor, DMA read, and DMA
write. These blocks are combined to create three different configurations:
• Memory to memory
• Memory to stream
• Stream to memory
The type of devices you are transferring data to and from determines the configuration to implement.
Examples of memory-mapped devices are PCI, PCIe and most memory devices. The Triple Speed
Ethernet MAC, DSP MegaCore functions and many video IPs are examples of streaming devices. A
recompilation is necessary each time you change the configuration of the SG-DMA controller core.
Functional Blocks and Configurations
The following sections describe each functional block and configuration.
UG-01085
2014.24.07
Functional Description
21-3
Scatter-Gather DMA Controller Core
Altera Corporation
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