EP80579 Datasheet, PDF (109/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
For communication using memory that is not coherent with the IA processor caches, or
for direct communication between AIOC agents (e.g. between ASU, TDM, and GigE
devices), the EP80579 may require software to insert explicit fencing operations to
ensure correct producer/consumer behavior. Details are discussed in Chapter 4.0,
“Signaling”.
2.3
DMA and Peer-to-Peer Data Transfers
The EP80579 provides multiple DMA and DMA-like features that are summarized here:
• IMCH EDMA Engine: The four channel IMCH “Enhanced DMA” (EDMA) engine
which supports DWORD aligned DMA. The EDMA engine supports memory-to-
memory and memory-to-PCIe transfers. Read DMA granularity ranges from 1 byte
to 4 Kilobytes. Write DMA granularity ranges from 1 to 256 bytes. The EDMA engine
supports different source/target byte alignments that are important for packet
processing, and is only programmable via IA PCI configuration space with
completions signaled via IA interrupts. The EDMA engine can support burst data
movement between “AIOC-direct memory” and IA coherent memory.
• IICH DMA: Supports IICH agents to/from memory, this is only used by USB and
SATA.
• LPC DMA: Supports LPC agents. See Chapter 20.0, “LPC DMA”.
• No Peer-to-Peer Reads: The IMCH does not support peer-to-peer reads.
Table 2-5 lists the supported DMA and peer-to-peer data transfer options.
Table 2-5. DMA and Peer-to-Peer Data Transfer Options
Usage
Model#
1
2
3
Operation
PCI DMA read
PCI DMA write
AIOC read
4
AIOC write
5
AIOC 3rd party read
6
AIOC 3rd party write
7
Peer-to-Peer PCI
Read
8
Peer-to-Peer PCI
Write
9
Mem-to-Mem
10
Mem-to-Memory
Mapped IO
Source
Destination
Initiator
DRAM
PCI Ex Device
DRAM or AIOC
device
AIOC device
DRAM
AIOC device (SSU)
PCI Ex device
DRAM
AIOC device (GE)
DRAM or AIOC device
(GE)
AIOC device (SSU)
DRAM
PCI Ex Device
PCI Ex Device
Device
Device
ASU
ASU
Not Supported
AIOC Master or PCI
Ex Device
DRAM
DRAM
PCI Ex Device only
DRAM
PCI Ex or AIOC
device
AIOC Master
or PCI Ex Device
EDMA Engine
EDMA Engine
Owner (Software)
IA device driver
IA device driver
IA, ASU
IA, ASU
ASU
ASU
AIOC Master Device
Driver
IA
IA
§§
August 2009
Order Number: 320066-003US
Intel^® EP80579 Integrated Processor Product Line Datasheet
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