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Figure 7-10, 9 translating large page references, Translation base – Epson ARM.POWERED ARM720T User Manual

Page 108: Coarse page table base address, L2 table index, Page index page base address level two descriptor, Page base address

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7: Memory Management Unit

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EPSON

ARM720T CORE CPU MANUAL

7.3.9

Translating large page references

Figure 7-10 shows the complete translation sequence for a 64KB large page.

Figure 7-10 Large page translation from a coarse page table

Because the upper four bits of the page index and low-order four bits of the coarse page table

index overlap, each coarse page table entry for a large page must be duplicated 16 times (in

consecutive memory locations) in the coarse page table.
If a large page descriptor is included in a fine page table, the high-order six bits of the page

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

a large page must therefore be duplicated 64 times.

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Translation base

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Table index

Translation base

Modified virtual address

Translation table base

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Table index

Page index

Level one descriptor

Physical address

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Coarse page table base address

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table index

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Page index

Page base address

Level two descriptor

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Coarse page table base address

L2 table index

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ap3

Page base address

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ap2 ap1 ap0

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