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Figure 7-11, 10 translating small page references, Translation base – Epson ARM.POWERED ARM720T User Manual

Page 109: Coarse page table base address, Level 2 table index, Page index page base address level two descriptor, Page base address

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7: Memory Management Unit

ARM720T CORE CPU MANUAL

EPSON

7-13

7.3.10

Translating small page references

Figure 7-11 shows the complete translation sequence for a 4KB small page.

Figure 7-11 Small page translation from a coarse page table

If a small page descriptor is included in a fine page table, the upper two bits of the page index

and low-order two bits of the fine page table index overlap. Each fine page table entry for a

small page must therefore be duplicated four times.

31

14 13

0

Translation base

31

14 13

2 1 0

0 0

Table index

Translation base

Modified virtual address

Translation table base

31

20 19

0

Table index

Page index

Level one descriptor

Physical address

31

0

Coarse page table base address

Domain 1

1

2 1

3

4

5

8

9

10

Level 2

table index

12 11

31

0

Page index

Page base address

Level two descriptor

31

0

Coarse page table base address

L2 table index

0

2 1

9

10

31

0

ap3

Page base address

0

0

ap2 ap1 ap0

0

1

C B

1

2

3

4

5

6

7

8

9

10

11

12

11

12