Control Processor to as many as fifteen line cards each via an
x1 connection. This usage model provides connectivity to
multiple line cards giving the processor control over a large
number of line cards in communication platforms.
The PEX 8619 supports the non-transparency feature.
Figure 6 illustrates a host system using an intelligent adapter
card.
Figure 6. Intelligent Adapter Usage
In this figure, the CPU on the adapter card is isolated from the
host CPU. The PEX 8619 non-transparent port allows the two
CPUs to be isolated but communicate with each other through
various registers that are designed in the PEX 8619 for that
purpose. Moreover, the internal DMA engine can be used to
copy or mirror the data between adapter cards so that
Figure 3. Control Plane Application
DMA in Control Planes for Large Systems
The DMA engine in the PEX8619 can alternatively be used to
perform housekeeping tasks, such as reading device status
information from the many endpoints available. This
particular usage model allows the DMA engine to perform the
many data transfers for endpoint status that would otherwise
be handled by the processor.
intelligent I/O adapter redundancy is achieved.
This model can be expanded to an Active-Standby failover
model. In this case, there is an Active host and a Standby host
ready to take over the system in the event the Active host fails.
The DMA engine in the PEX8619 can be used to mirror the
data between hosts thus minimizing the failover time.
Generic Data Mover
The DMA engine in the PEX8619 is very flexible. It
implements Four DMA channels capable of saturating a x8
Gen2 PCI Express link. Furthermore, it supports a Descriptor
Ring approach in which the descriptors can be placed in
external host memory or internal to the PEX8619. The DMA
engine can move data from any port to any port including the
same port. That is, the source and destination for a DMA
transfer can be on the same PEX8619 port. Figure 7 shows
two PCIe endpoints and a PEX8619 device connected through
a PCIe switch. In this example, the PCIe endpoints take
advantage of the DMA capabilities in the PEX8619 to move
data from PCIe2 to PCIe1.
Figure 4. PEX8619 DMA in a Packet Router
Distributed Computing
The PEX 8619 is well suited for distributed computing
applications. Once programmed, the DMA engine in the
PEX8619 transfers the data between servers and through the
NT port at a high rate. The processor can focus all of its
computing cycles manipulating the large amounts of data
received.
Figure 7. Generic Data Mover
Figure 5. Distributed Computing
Intelligent Adapter Card Redundancy
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