AMD-761 Datasheet, PDF (156/264 Pages) Advanced Micro Devices – AMD-761-TM System Controller Software/BIOS Design Guide

Preliminary Information
AMD-761™ System Controller Software/BIOS Design Guide
24081D—February 2002
GART Directory Base Address
31
30
29
Bit
Reset
0
0
0
R/W
23
22
21
Bit
Reset
0
0
0
R/W
15
Bit
Reset
0
R/W
14
13
GART_Dir_Base_Addr
0
0
R/W
7
6
5
Bit
Reset
0
0
0
R/W
28
27
GART_Dir_Base_Addr
0
0
R/W
20
19
GART_Dir_Base_Addr
0
0
R/W
12
11
0
0
4
3
Reserved
0
0
R
Bar1 + 0x04
26
25
24
0
0
0
18
17
16
0
0
0
10
9
8
Reserved
0
0
0
R
2
1
0
0
0
0
Register Description
Bit Definitions
Bit Name
31–12 GART_Dir_Base
_Addr
11–0 Reserved
GART Directory Base Address (Bar1 + 0x04)
Function
GART Directory Base Address
These bits define the base address of the GART directory that is located in physical system
memory. These 20 bits correspond to the 20 most significant bits of the 32-bit GART
directory base address that is aligned on a 4-Kbyte page boundary. Twenty bits provide
4-Kbyte resolution, which is the minimum allowable size of the GART. A value other than 0
defines a valid base address.
Reserved
Programming Notes
144
AMD-761™ System Controller Programmer’s Interface
Chapter 2