32579B

Core Logic Module - X-Bus Expansion Interface - Function 5

 

 

 

 

 

Table 6-39. F5: PCI Header Registers for X-Bus Expansion (Continued)

 

 

 

 

 

Bit

 

Description

 

 

 

 

 

 

Index 1Ch-1Fh

Base Address Register 3 - F5BAR3 (R/W)

Reset Value: 00000000h

Reserved. Reserved for possible future use by the Core Logic module.

 

Configuration of this register is programmed through the F5BAR3 Mask Register (F5 Index 4Ch).

 

 

 

 

Index 20h-23h

Base Address Register 4 - F5BAR4 (R/W)

Reset Value: 00000000h

Reserved. Reserved for possible future use by the Core Logic module.

 

Configuration of this register is programmed through the F5BAR4 Mask Register (F5 Index 50h).

 

 

 

 

Index 24h-27h

Base Address Register 5 - F5BAR5 (R/W)

Reset Value: 00000000h

Reserved. Reserved for possible future use by the Core Logic module.

 

Configuration of this register is programmed through the F5BAR5 Mask Register (F5 Index 54h).

 

 

 

 

Index 28h-2Bh

Reserved

Reset Value: 00h

 

 

 

Index 2Ch-2Dh

Subsystem Vendor ID (RO)

Reset Value: 100Bh

 

 

 

Index 2Eh-2Fh

Subsystem ID (RO)

Reset Value: 0505h

 

 

 

Index 30h-3Fh

Reserved

Reset Value: 00h

 

 

 

Index 40h-43h

F5BAR0 Mask Address Register (R/W)

Reset Value: FFFFFFC1h

To use F5BAR0, the mask register should be programmed first. The mask register defines the size of F5BAR0 and whether the

accessed offset registers are memory or I/O mapped.

 

Note: Whenever a value is written to this mask register, F5BAR0 must also be written (even if the value for F5BAR0 has not

 

changed).

 

 

 

 

 

 

Memory Base Address Register (Bit 0 = 0)

 

 

 

 

 

31:4

 

Address Mask. Determines the size of the BAR.

 

 

 

— Every bit that is a 1 is programmable in the BAR.

 

 

 

— Every bit that is a 0 is fixed 0 in the BAR.

 

 

 

Since the address mask goes down to bit 4, the smallest memory region is 16 bytes, however, the PCI specification sug-

 

 

gests not using less than a 4 KB address range.

 

 

 

 

3

 

Prefetchable. Indicates whether or not the data in memory is prefetchable. This bit should be set to 1 only if all the following

 

 

are true:

 

 

 

 

— There are no side-effects from reads (i.e., the data at the location is not changed as a result of the read).

 

 

— The device returns all bytes regardless of the byte enables.

 

 

 

— Host bridges can merge processor writes into this range without causing errors.

 

 

 

— The memory is not cached from the host processor.

 

 

 

0: Data is not prefetchable. This value is recommended if one or more of the above listed conditions is not true.

 

 

1: Data is prefetchable.

 

 

 

 

 

 

 

2:1

 

Type.

 

 

 

 

00: Located anywhere in the 32-bit address space

 

 

 

01: Located below 1 MB

 

 

 

 

10: Located anywhere in the 64-bit address space

 

 

 

11: Reserved

 

 

 

 

 

 

0

 

This bit must be set to 0, to indicate memory base address register.

 

 

 

 

I/O Base Address Register (Bit 0 = 1)

 

 

 

 

 

 

31:2

 

Address Mask. Determines the size of the BAR.

 

 

 

— Every bit that is a 1 is programmable in the BAR.

 

 

 

— Every bit that is a 0 is fixed 0 in the BAR.

 

 

 

Since the address mask goes down to bit 2, the smallest I/O region is 4 bytes, however, the PCI Specification suggests not

 

 

using less than a 4 KB address range.

 

 

 

 

 

 

1

 

Reserved. Must be set to 0.

 

 

 

 

 

 

0

 

This bit must be set to 1, to indicate an I/O base address register.

 

 

 

 

 

 

 

 

 

 

278

 

 

AMD Geode™ SC1200/SC1201 Processor Data Book

Page 278
Image 278
AMD SC1200 manual Bit Description Index 1Ch-1Fh, Index 20h-23h, Index 24h-27h, Index 28h-2Bh, Base Address Register Bit 0 =