IDT Transparent Mode Operation
Port Configuration Space Organization
PES12N3 User Manual
9 - 6
June 7, 2006
Notes
Configuration Requests
The PCI-PCI bridges associated with ports A, B and C all have configuration registers that may be
accessed with Type 0 configuration read and write requests. PCIe allows multiple outstanding configuration
read and write requests. The PCI-PCI bridges in the PES12N3 each support a maximum of four
outstanding configuration requests. Issuing more than four outstanding configuration requests to any of
these entities may result in configuration requests being dropped.
Configuration accesses to different entities within the PES12N3 may complete out-of-order and may
limit the utility of multiple outstanding PCIe configuration accesses. For example, a configuration access
that modifies a secondary or subordinate bus number which is immediately followed by a Type 1 configura-
tion access that relies on the modified value for routing may result in an error when issued concurrently, but
execute properly when issued in sequence. Configuration accesses to any particular entity always
complete in order.
Port Configuration Space Organization
The organization of port A, B and C configuration space is shown in Figure 9.2. While all three ports
share the same basic layout, only port A (the upstream port) has switch control and status registers and
only ports B and C (downstream ports) have an MSI capability structure. Port A does not contain an MSI
capability structure since it does not have an associated hot-plug controller that generates interrupts.
Summary of Contents for 89HPES12N3
Page 10: ...IDT Table of Contents PES12N3 User Manual iv June 7 2006 Notes...
Page 14: ...IDT List of Figures PES12N3 User Manual viii June 7 2006 Notes...
Page 36: ...IDT Clocking Reset and Initialization Reset PES12N3 User Manual 2 8 June 7 2006 Notes...
Page 40: ...IDT Link Operation Slot Power Limit Support PES12N3 User Manual 3 4 June 7 2006 Notes...
Page 50: ...IDT Switch Operation Switch Core Errors PES12N3 User Manual 4 10 June 7 2006 Notes...
Page 54: ...IDT Power Management Active State Power Management PES12N3 User Manual 5 4 June 7 2006 Notes...
Page 62: ...IDT Hot Plug and Hot Swap Hot Swap PES12N3 User Manual 6 8 June 7 2006 Notes...
Page 78: ...IDT SMBus Interfaces Slave SMBus Interface PES12N3 User Manual 7 16 June 7 2006 Notes...
Page 148: ...IDT Test and Debug SerDes Test Clock PES12N3 User Manual 10 6 June 7 2006...
Page 158: ...IDT JTAG Boundary Scan Usage Considerations PES12N3 User Manual 11 10 June 7 2006 Notes...