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Zynq-7000 AP SoC Technical Reference Manual www.xilinx.com 80
UG585 (v1.11) September 27, 2016
Chapter 3: Application Processing Unit
The fields mentioned in Figure 3-7 are discussed in Description of Page Table Entry Fields.
Figure 3-8 summarizes the address translation process when using two layers of page tables. The bits
[31:20] of the virtual address are used to index into the 4096-entry L1 page table, where the base
address is given by the CP15 TTB register. The L1 page table entry points to an L2 page table, which
contains 256 entries. Bits [19:12] of the virtual address are used to select one of those entries which
then gives the base address of the page. The final physical address is generated by combining that
base address with the remaining bits of the physical address.
X-Ref Target - Figure 3-7
Figure 3-7: L2 Page Table Entry Format
UG585_c3_08_1022112
Fault IGNORE
1
0
00
01
BCAPSBZ
TEX
[2:0]
S
nG
APX
1BCAP
TEX
[2:0]
S
nG
APX
XN
239451011 786151631 1314 12
Large
Page
Large Page Base Address
Small Page Base Address
Small
Page
XN