Control Register 4 (CR4) Extensions
3-11
18524C/0—Nov1996
AMD-K5 Processor Technical Reference Manual
Table 3-3. Page-Table Entry (PTE) Fields
Bit
Mnemonic
Description
Function
31–12
BASE
Physical Base
Address
The physical base address of a 4-Kbyte page.
11–9
AVL
Available to Soft-
ware
Software may use the field to store any type of information.
When the page-table entry is not present (P bit cleared), bits 31–1
become available to software.
8
G
Global
0 = local, 1 = global.
7
PS
Page Size
This bit is ignored in page-table entries, although clearing it to 0
preserves consistent usage of this bit between page-table and
page-directory entries.
6
D
Dirty
The processor sets this bit to 1 during a write to the page that is
mapped by this page-table entry.
0 = not written, 1 = written.
5
A
Accessed
The processor sets this bit to 1 during a read or write to any page
that is mapped by this page-table entry.
0 = not read or written, 1 = read or written.
4
PCD
Page Cache Disable
Specifies cacheability for all locations in the page mapped by this
page-table entry. Whether a location is actually cached also
depends on several other factors.
0 = cacheable page, 1 = non-cacheable.
3
PWT
Page Writethrough
Specifies writeback or writethrough cache protocol for all loca-
tions in the page mapped by this page-table entry. Whether a
location is actually cached in a writeback or writethrough state
also depends on several other factors.
0 = writeback, 1 = writethough.
2
U/S
User/Supervisor
0 = user (any CPL), 1 = supervisor (CPL < 3).
1
W/R
Write/Read
0 = read or execute, 1 = write, read, or execute.
0
P
Present
0 = not valid, 1 = valid.
Summary of Contents for AMD-K5
Page 1: ...AMD K5 Processor Technical Reference Manual TM...
Page 10: ...x AMD K5 Processor Technical Reference Manual 18524C 0 Nov1996...
Page 24: ...1 4 Overview AMD K5 Processor Technical Reference Manual 18524C 0 Nov1996...
Page 54: ...2 30 Internal Architecture AMD K5 Processor Technical Reference Manual 18524C 0 Nov1996...
Page 116: ...4 26 Performance AMD K5 Processor Technical Reference Manual 18524C 0 Nov1996...
Page 356: ...6 44 System Design AMD K5 Processor Technical Reference Manual 18524C 0 Nov1996...
Page 380: ...7 24 Test and Debug AMD K5 Processor Technical Reference Manual 18524C 0 Nov1996...
Page 396: ...A 16 AMD K5 Processor Technical Reference Manual 18524C 0 Nov1996...
Page 406: ...I 10 Index AMD K5 Processor Technical Reference Manual 18524C 0 Nov1996...