Intel 253668-032US User Manual

Vol. 3 11-31

MEMORY CACHE CONTROL

Reserved*

03H

Write-through (WT)

04H

Write-protected (WP)

05H

Writeback (WB)

06H

Reserved*

7H through FFH

NOTE:

* Use of these encodings results in a general-protection exception (#GP).

Figure 11-4. Mapping Physical Memory With MTRRs

Table 11-8. Memory Types That Can Be Encoded in MTRRs (Contd.)

FFFFFFFFH

80000H

BFFFFH

C0000H

FFFFFH

100000H

7FFFFH

512 KBytes

256 KBytes

8 fixed ranges

16 fixed ranges

64 fixed ranges

Variable ranges

(64-KBytes each)

(16 KBytes each)

(4 KBytes each)

(from 4 KBytes to

maximum size of

Address ranges not

Physical Memory

mapped by an MTRR

are set to a default type

physical memory)