Filter
Top Products
42 Intel
®
41210 Serial to Parallel PCI Bridge Developer’s Manual
Addressing
5.2 Secondary PCI Devices
Devices on the secondary PCI bus can be configured as private devices and hidden from BIOS and
host software. Devices are hidden by inhibiting the assertion of the IDSEL input of the device
during configuration cycles. This feature is configured through the BINIT register. Public and private
devices are supported according to Table 20.
5.3 Configuration-Space Access
The 41210 supports configuration-space accesses from PCI Express* using both the legacy PCI-to-
PCI Bridge Specification, Revision 2.3 access mechanism and the enhanced PCI Express*
configuration-space access mechanism. For local initialization, the 41210 also supports
configuration-pace accesses from the SMBus port and secondary PCI bus.
5.3.1 PCI Express* Configuration Access
The PCI-to-PCI Bridge Specification, Revision 1.1 defines the configuration-space region of a PCI
function to be up to 256 B. PCI Express* extends the PCI configuration space from 256 B to 4 K.
The region up to 256 B can be accessed using the mechanism for configuration accesses defined in
the PCI-to-PCI Bridge Specification, Revision 1.1. The region above 256 B is accessible only by
means of the enhanced configuration access mechanism defined in PCI Express*. This mechanism
utilizes a flat memory-mapped address region to access the configuration space. The core-logic
chipset converts the legacy PCI-to-PCI Bridge Specification, Revision 1.1 or the enhanced PCI
Express* configuration-space accesses into PCI Express* configuration cycles.
Table 20. Secondary PCI Device Addressing
Device Number
Signal Used for
IDSEL Input
Public/Private Notes
0 AD16 Reserved Dedicated for bridge
1AD17
Public or Private
Based on the device-hiding enable bit
(bit[2] of the BINIT register)
Available for secondary PCI devices
2AD18
3AD19
4AD20
5AD21
6AD22
7AD23
8AD24
Reserved
Used to address extended configuration
space of bridge
Based on the upstream-configuration
enable bit (bit[1] of the BINIT register)
9AD25
10 (0xA) AD26
11 (0xB) AD27
12 (0xC) AD28
Public Available for secondary PCI devices
13 (0xD) AD29
14 (0xE) AD30
15 (0xF) AD31