Chapter 7 Software Architecture
PEX 8532 Software Model
7.1
The PEX 8532 requires software support in the following areas:
• Switch configuration and configuration of all switch downstream links
• Moving data forward and back through the links
• Monitoring and servicing interrupts throughout the connected fabric
• Monitoring and adjusting performance-related mechanisms
The Configuration Mechanisms are straightforward and use Conventional PCI software structures and
procedures to set up and identify all ports and links connected through the PEX 8532. The PEX 8532
supports an optional serial EEPROM interface, to simplify downloading of Configuration data to the
switch. (Refer to Section 7.3.)
After the PEX 8532 and its links are set up, data can be routed through the PEX 8532, from one port to
another. Responses and other communications are returned, by way of the same links, to the Initiator.
The PEX 8532 is transparent to these Data transfers. (Refer to Section 7.3.1.3.)
When errors occur during data transfer due to data corruption in the internal RAM, or an external device
violates its credits, an interrupt is returned, through the internal fabric to the Host, identifying the
problem. It is the responsibility of the Host software to implement interrupt-service routines to handle
the problem. (Refer to Chapter 6, “Interrupts,” for further details.)
ExpressLane PEX 8532AA/BA/BB/BC 8-Port/32-Lane Versatile PCI Express Switch Data Book
Copyright © 2007 by PLX Technology, Inc. All Rights Reserved – Version 1.6
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