Integrated Functions (Continued)
Physical Address Map
FFFFFFFFh (4 GB)
MAX
ROM Access
(256 KB)
FFFC0000h
PCI Access
GX_BASE+1000000h
Graphics Memory
(Frame Buffer, etc.)
GX_BASE+800000h
SMM System Code
GX_BASE+400000h
GX_BASE+9000h
Power Management Registers
(See Table 6-1 on page 179)
GX_BASE+8500h
GX_BASE+8400h
GX_BASE+8300h
GX_BASE+8100h
Memory Controller Registers
(See Table 4-15 on page 108)
DRAM Map
FFFF FFFFh
MAX
Display Controller Registers
(See Table 4-29 on page 136)
Graphics Memory
(Frame Buffer, etc.)
Graphics Pipeline Registers
(See Table 4-24 on page 124)
Internal Bus IF Unit Registers
(See Table 4-9 on page 101)
GX_BASE+8000h
GX_BASE+1000h
PCI Access
Scratchpad
(See Table 4-5 on page 97)
PCI Access
PCI Access
GX_BASE (See Table
4-1 on page 92)
*GBADD or Top of DRAM
Extended Memory
100000h (1 MB)
*Top of DRAM
100000h (1 MB)
E8000h
Extended Memory
System BIOS
Video BIOS
Shadowed System BIOS
E8000h
Shadowed Video BIOS
E0000h
E0000h
UMBs and
Expansion ROMs
UMBs and Expansion ROMs
C0000h
C0000h
VGA/MDA
Frame Buffers
(Soft VGA and/or PCA/ISA)
SMM System Code
A0000h (640 KB)
Conventional Memory
0h
A0000h (640 KB)
0h
Conventional Memory
* See BC_DRAM_TOP Table 4-10 on page 101 or MC_GBASE_ADD on page 111.
Figure 4-2. Geode™ GXm Processor Memory Space
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