Intel 815 Benutzerhandbuch
Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0
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Figure 8.
GTT Mapping
Virtual
Graphics
Memory
Base
Base + 64 MB
TOM
Base + 32 MB
64 KB
0
64 MB
Graphics Engine
Address Space
Graphics
Translation Table
(GTT)
4 KB
4 KB
0 KB
GTT Maps 4KB blocks of Virtual
Graphics Memory to 4 KB pages in
System Memory
System Memory
31
0
31
0
4 GB
31
0
GTT Maps 4KB blocks of
Virtual Graphics Memory
to 4 KB pages in Display
Cache
Optional Display
Cache
gtt.vsd
3.4.2.
Memory Buffers for GC’s Instruction Interface
The GC provides two Ring Buffer (RB) mechanisms through which instructions can be passed to the
GMCH’s Instruction Parser. In addition, the GC provides for the execution of instruction sequences
external to the ring buffers. These sequences are called "batch buffers", and are initiated through the use
of GFXCMDPARSER_BATCH_BUFFER instructions that specify the starting address and length of the
batch buffers. For detailed information on these buffers, refer to the Programming Interface Chapter.
GMCH’s Instruction Parser. In addition, the GC provides for the execution of instruction sequences
external to the ring buffers. These sequences are called "batch buffers", and are initiated through the use
of GFXCMDPARSER_BATCH_BUFFER instructions that specify the starting address and length of the
batch buffers. For detailed information on these buffers, refer to the Programming Interface Chapter.