MPU Memory Management Unit
2-38
2.7.6.7
Translating Small Page References
Figure 2–17 illustrates the complete translation sequence for a 4K-byte small
page. If a small page descriptor is included in a fine page table, the upper two
bits of the index of the page overlap the lower two bits of the index of the fine
page table. In other words, four consecutive entries must be used for a small
page in a fine page table.
Figure 2–17. Small Page Translation
31
20 19
18
12
14 13
2 1
0
0
0
Virtual address
Table index
L2 table index
Translation base
Translation table index
First-level descriptor
Table index
Translation base
31
31
31
0
0
0
14 13
L2 table index
C B
Domain
1
1 0
Page table base address
Page table base address
31
0
9 8
5 4
2 1
10
10 9
Page base address
31
0
Page index
Page base address
31
0
8
12
12 11
Page index
1
0
2 1
0
12 1110
1
2
3
4
5
6
7
8
9
ap0
Second-level descriptor
Physical address
12 11
0
ap1
ap2
ap3