Second-Level Descriptors For Coarse; Second-Level Descriptors For Fine; First-Level Descriptors - Intel XScale Core Developer's Manual

Intel XScale® Core Developer's Manual
Programming Model
Table 2-8.

First-level Descriptors

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Section base address
Table 2-9. Second-level Descriptors for Coarse Page Table
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Table 2-10. Second-level Descriptors for Fine Page Table
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The TEX (Type Extension) field is present in several of the descriptor types. In the core, only the
LSB of this field is defined; this is called the X bit. The remaining bits should be programmed as
zero (SBZ).
A Small Page descriptor does not have a TEX field. For these descriptors, TEX is implicitly zero;
that is, they operate as if the X bit had a '0' value.
The X bit, when set, modifies the meaning of the C and B bits. Description of page attributes and
their encoding can be found in
30
Coarse page table base address
Fine page table base address
Large page base address
Small page base address
Extended small page base address
Large page base address
Small page base address
Tiny Page Base Address
Chapter 3, "Memory
January, 2004
SBZ
SBZ TEX AP
SBZ
SBZ
TEX AP3
AP3
SBZ
SBZ
TEX AP3
AP3
Management".
8 7 6 5 4 3 2 1
0 0
P Domain SBZ 0 1
P Domain 0 C B 1 0
P Domain SBZ 1 1
8 7 6 5 4 3 2 1
0 0
AP2 AP1 AP0 C B 0 1
AP2 AP1 AP0 C B 1 0
TEX AP C B 1 1
8 7 6 5 4 3 2 1
0 0
AP2 AP1 AP0 C B 0 1
AP2 AP1 AP0 C B 1 0
TEX AP C B 1 1
Developer's Manual
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