AMD 4.4.5 Switch User Manual

AMD Confidential
User Manual November 21
, 2008
102 Chapter 7: Device Configuration
7.16 AMD-8151 AGP Bridge Device
The AMD-8151 AGP Bridge Device tunnel is a HyperTransport tunnel that provides an
AGP bridge. In general, AMD-8151 would be connected in a non-coherent
HyperTransport chain between the host bridge and the Southbridge.
The AMD-8151 has three types of interfaces, HyperTransport, AGP, and INT/IOAPIC
buses. The AMD-8151 has two HyperTransport links, HT0 and HT1, that can connect to
other non-coherent HyperTransport link-capable devices. HT0 should be connected to the
upstream link (the one closest to the host bridge) and HyperTransport1 should be
connected to the downstream link. The AGP interface should be connected to an AGP
graphics device. The INT_IOAPIC bus should be connected to the Southbridge; it routes
interrupt signals from the AGP bus to the Southbridge.
Initialization and Reset State
When first initialized or reset, the AMD-8151 registers are set to their default state. This
is described in detail in the AMD-8151 datasheet.
Contents of a BSD
The current state of all PCI configuration registers and any internal state variables are
saved in the BSD.
Configuration Options
The AMD-8151 device allows you to set its Revision number as shown in Figure 7-29.
Figure 7-29: AMD-8151™ Device Properties Dialog