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Core Logic Module
(Continued)
5.3
The Core Logic module is a multi-function module. Its reg-
ister space can be broadly divided into three categories in
which specific types of registers are located:
REGISTER DESCRIPTIONS
1)
Chipset Register Space (F0-F3, F5; Note that F4 is
Reserved): Comprised of five separate functions, each
with its own register space, consisting of PCI header
registers and configuration registers.
The PCI header is a 256-byte region used for configur-
ing a PCI device or function. The first 64 bytes are the
same for all PCI devices and are predefined by the
PCI specification. These registers are used to config-
ure the PCI for the device. The rest of the 256-byte
region is used to configure the device or function itself.
2)
USB Controller Register Space (PCIUSB): Consists of
the standard PCI header registers. The USB controller
supports three ports and is OpenHCI compliant.
3)
ISA Legacy Register Space (I/O Ports): Contains all
the legacy compatibility I/O ports that are internal,
trapped, shadowed, or snooped.
The following subsections provide:
A brief discussion on how to access the registers
located in PCI Configuration Space.
Core Logic module register summaries.
Bit formats for Core Logic module registers.
5.3.1
Configuration cycles are generated in the processor. All
configuration registers in the Core Logic module are
One Configuration Mechanism. This mechanism uses two
DWORD I/O locations at 0CF8h and 0CFCh. The first loca-
tion (0CF8h) references the Configuration Address register.
The second location (0CFCh) references the Configuration
Data Register (CDR).
PCI Configuration Space and Access Methods
To access PCI configuration space, write the Configuration
Address (0CF8h) Register with data that specifies the Core
Logic module as the device on PCI being accessed, along
with the configuration register offset. On the following
cycle, a read or write to the Configuration Data Register
(CDR) causes a PCI configuration cycle to the Core Logic
module. Byte, WORD, or DWORD accesses are allowed to
CDR at 0CFCh, 0CFDh, 0CFEh, or 0CFFh.
The Core Logic module has seven PCI configuration regis-
ter sets, one for each function F0-F3, F4 (Reserved), F5,
and USB (PCIUSB). Base Address Registers (BARx) in
F0-F3, F5 and PCIUSB set the base addresses for addi-
tional I/O or memory mapped configuration registers for
each function.
Table 5-13 shows the PCI Configuration Address Register
(0CF8h) and how to access the PCI header registers.
Table 5-13. PCI Configuration Address Register (0CF8h)
31
30
24
23
16
15
11
10
8
7
2
1
0
Configuration
Space Mapping
Reserved
Bus Number
Device Number
Function
Index
DoubleWord
00
1 (Enable)
000 000
0000 0000
xxxx x
(Note)
xxx
xxxx xx
00 (Always)
Function 0 (F0): Bridge Configuration, GPIO and LPC Configuration Register Space
80h
0000 0000
1001 0 or 1000 0
000
Index
Function 1 (F1): SMI Status and ACPI Timer Configuration Register Space
80h
0000 0000
1001 0 or 1000 0
001
Index
Function 2 (F2): IDE Controller Configuration Register Space
80h
0000 0000
1001 0 or 1000 0
010
Index
Function 3 (F3): XpressAUDIO Configuration Register Space
80h
0000 0000
1001 0 or 1000 0
011
Index
Function 4 (F4): Reserved
80h
0000 0000
1001 0 or 1000 0
100
Index
Function 5 (F5): X-Bus Expansion Configuration Register Space
80h
0000 0000
1001 0 or 1000 0
101
Index
PCIUSB: USB Controller Configuration Register Space
80h
0000 0000
1001 1 or 1000 1
000
Index
Note:
The device number depends upon the IDSEL Strap Override bit (F5BAR0+I/O Offset 04h[0]). This bit allows selection of the
address lines to be used as the IDSEL. By Default: IDSEL = AD28 (1001 0) for F0-F3, F5; AD29 (1001 1) for PCIUSB.