GXM Datasheet, PDF (93/244 Pages) National Semiconductor (TI) – Geode™ GXm Processor Integrated x86 Solution with MMX Support

Integrated Functions (Continued)
FFFF FFFFh
MAX
DRAM Map
Graphics Memory
(Frame Buffer, etc.)
Physical Address Map
ROM Access
(256 KB)
PCI Access
Graphics Memory
(Frame Buffer, etc.)
SMM System Code
Power Management Registers
(See Table 6-1 on page 179)
Memory Controller Registers
(See Table 4-15 on page 108)
Display Controller Registers
(See Table 4-29 on page 136)
Graphics Pipeline Registers
(See Table 4-24 on page 124)
Internal Bus IF Unit Registers
(See Table 4-9 on page 101)
PCI Access
Scratchpad
(See Table 4-5 on page 97)
FFFFFFFFh (4 GB)
MAX
FFFC0000h
GX_BASE+1000000h
GX_BASE+800000h
GX_BASE+400000h
GX_BASE+9000h
GX_BASE+8500h
GX_BASE+8400h
GX_BASE+8300h
GX_BASE+8100h
GX_BASE+8000h
GX_BASE+1000h
*GBADD or Top of DRAM
100000h (1 MB)
E8000h
E0000h
C0000h
Extended Memory
Shadowed System BIOS
Shadowed Video BIOS
UMBs and
Expansion ROMs
SMM System Code
A0000h (640 KB)
0h
Conventional Memory
PCI Access
PCI Access
Extended Memory
System BIOS
Video BIOS
UMBs and Expansion ROMs
VGA/MDA
Frame Buffers
(Soft VGA and/or PCA/ISA)
Conventional Memory
GX_BASE (See Table
4-1 on page 92)
*Top of DRAM
100000h (1 MB)
E8000h
E0000h
C0000h
A0000h (640 KB)
0h
* 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
Revision 3.1
93
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