Texas Instruments PCI7421, PCI7411 TI Extension Base Address Register, TI extension base address

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.

7−7