Notes
PES16NT2 User Manual
10 - 1
April 15, 2008
®
Chapter 10
Non-Transparent Mode
Operation
Introduction
The PCIe® architectural model is one in which a root, typically the main CPU, is responsible for config-
uring a tree of endpoints (i.e., a hierarchy of virtual PCI buses). Once configured, any endpoint or root may
“initiate transactions. The root and endpoints share a common address space with routing configured in
PCI-PCI bridges.
A limitation of the PCIe architectural model is that it allows only a single root and that the root and all of
the endpoints must share a common address space. This limitation may be overcome through the use of a
non-transparent bridge. A non-transparent bridge allows two roots or PCIe trees to be interconnected with
one or more shared address windows between them.
Note:
Port C of the PES16NT2 can operate in either transparent mode or non-transparent mode.
When the PES16NT2 is configured during a fundamental reset to operate in non-transparent mode or
non-transparent mode with serial EEPROM initialization, the device functionally operates as illustrated in
Figure 10.1. In this mode, the PES16NT2 may be logically viewed as consisting of two PCI-PCI transparent
bridges, one per port and an internal virtual PCI bus. Port C is the non-transparent port. Beneath the trans-
parent bridge associated with port C are two endpoints interconnected by non-transparent bridge function-
ality. When viewed externally, port C appears as an end-point device. When viewed internally, the non-
transparent bridge beneath the PCI-PCI bridge associated with port C appears as an end-point device.
The endpoint and non-transparent bridge functionality closest to the PCI-PCI bridge is referred to as the
internal side
of the non-transparent bridge. The endpoint and non-transparent bridge associated with the
port C link is referred to as the
external side
of the non-transparent bridge.
The non-transparent bridge requires configuration following a fundamental reset before it will bridge
transactions between the internal and external sides. This configuration may be performed by the root asso-
ciated with the internal side (port A), root associated with the external side (Port C), serial EEPROM, or
master on the slave SMBus interface.
Associated with the upstream port and port C is a 4 KB configuration space and a Type 1 configuration
header. The organization and function of these configuration spaces is exactly the same as in transparent
mode and is described in Port Configuration Space Organization on page 9-5. Associated with the down-
stream non-transparent port is a 4 KB configuration space and Type 1 configuration header corresponding
to the PCI-PCI bridge on the virtual PCI bus. The organization and function of this configuration space is
exactly the same as in transparent mode except for the following.
Содержание 89HPES16NT2
Страница 14: ...DT List of Figures PES16NT2 User Manual viii April 15 2008 Notes...
Страница 20: ...IDT Register List PES16NT2 User Manual xiv April 15 2008 Notes...
Страница 32: ...IDT PES16NT2 Device Overview PES16NT2 User Manual 1 12 April 15 2008 Notes...
Страница 44: ...IDT Clocking Reset and Initialization Clock Operation PES16NT2 User Manual 2 12 April 15 2008 Notes...
Страница 50: ...IDT Link Operation PES16NT2 User Manual 3 6 April 15 2008 Notes...
Страница 62: ...IDT Power Management PES16NT2 User Manual 5 4 April 15 2008 Notes...
Страница 78: ...IDT SMBus Interfaces PES16NT2 User Manual 6 16 April 15 2008 Notes...
Страница 83: ...IDT NTB Upstream Port Failover PES16NT2 User Manual 7 5 April 15 2008 Notes...
Страница 84: ...IDT NTB Upstream Port Failover PES16NT2 User Manual 7 6 April 15 2008 Notes...
Страница 130: ...IDT Transparent Mode Operation PES16NT2 User Manual 9 44 April 15 2008 Notes...
Страница 284: ...IDT Non Transparent Mode Operation PES16NT2 User Manual 10 154 April 15 2008 Notes...