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9 ti extension base address register – Texas Instruments Dual/Single Socket CardBus and UntraMedia Controller PCI7621 User Manual

Page 167

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7−7

7.9

TI Extension Base Address Register

The TI extension base address register is programmed with a base address referencing the memory-mapped TI
extension registers. When BIOS writes all 1s to this register, the value read back is FFFF C000h, indicating that at
least 16K bytes of memory address space are required for the TI registers. See Table 7−8 for a complete description
of the register contents.

Bit

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

Name

TI extension base address

Type

RW

RW

RW

RW

RW

RW

RW

RW

RW

RW

RW

RW

RW

RW

RW

RW

Default

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Bit

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

Name

TI extension base address

Type

RW

RW

R

R

R

R

R

R

R

R

R

R

R

R

R

R

Default

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Register:

TI extension base address

Offset:

14h

Type:

Read/Write, Read-only

Default:

0000 0000h

Table 7−8. TI Base Address Register Description

BIT

FIELD NAME

TYPE

DESCRIPTION

31−14

TIREG_PTR

RW

TI register pointer. This field specifies the upper 18 bits of the 32-bit TI base address register. The
default value for this field is all 0s.

13−4

TI_SZ

R

TI register size. This field returns 0s when read, indicating that the TI registers require a 16K-byte
region of memory.

3

TI_PF

R

TI register prefetch. Bit 3 returns 0 when read, indicating that the TI registers are nonprefetchable.

2−1

TI_MEMTYPE

R

TI memory type. This field returns 0s when read, indicating that the TI base address register is 32 bits
wide and mapping can be done anywhere in the 32-bit memory space.

0

TI_MEM

R

TI memory indicator. Bit 0 returns 0 when read, indicating that the TI registers are mapped into system
memory space.