AGP Subsystem

Figure 7-1. GART Table Usage for 4k Pages

39

11

0

AGP address

 

Offset

 

 

 

12b

AGP address (39:12) - APBASE(39:12)

(If less than APBASE+Aperture)

 

 

 

 

 

24b

 

 

 

 

 

 

 

 

18b

 

24 Bit

+

 

 

 

 

 

 

 

 

 

 

 

GART Entry

 

(16b if256 MB

 

 

 

 

of GART space)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

GART Table

36b Main Memory Address

Figure 7-2. GART Table Usage for 4 MB Pages

39

21

0

AGP address

 

Offset

 

 

 

22b

AGP address (39:22) - APBASE(39:22)

(If less than APBASE+Aperture)

 

 

 

 

 

 

14b

 

 

13b

 

14 Bit

+

 

 

 

 

 

 

 

 

 

 

 

(8b if 1 GB GART,

GART Entry

 

 

 

6b if 256 MB GART)

GART Table

36b Main Memory Address

7-2

Intel® 460GX Chipset Software Developer’s Manual