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Zynq-7000 AP SoC Technical Reference Manual www.xilinx.com 81
UG585 (v1.11) September 27, 2016
Chapter 3: Application Processing Unit
Description of Page Table Entry Fields
Memory Access Permissions (AP and APx)
The access permission (AP and APX) bits in the page table entry give the access permission for a
page. An access which does not have the necessary permission (or which faults) is aborted. On a data
access, this results in a precise data abort exception. On an instruction fetch, the access is marked as
aborted and if the instruction is not subsequently flushed before execution, a pre-fetch abort
exception is taken. Information about the address of the faulting location and the reason for the fault
is stored in CP15 (the fault address and fault status registers). The abort handler can then take
appropriate action. Table 3-2 lists the access permission encodings.
X-Ref Target - Figure 3-8
Figure 3-8: Generating a Physical Address from an L2 Page Table Entry
Translation Table Base Address
31 14 13 0
31 14 13 2 10
31 9 2 10
01
10
10
31 20 19 12 11 0
UG585_c3_09_102112
Level 1 Descriptor Address
Level 2 Table Base Address
31 9 2 1010
Level 2 Descriptor Address
31 11 2 1012
Small Page Base Address
31 11 012
Physical Address
Level 1
Table
Level 2
Table
TTB
2TB
Virtual Address