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Zynq-7000 AP SoC Technical Reference Manual www.xilinx.com 78
UG585 (v1.11) September 27, 2016
Chapter 3: Application Processing Unit
The page table entry for a section (or super-section) contains the physical base address used to
translate the virtual address. Many other bits listed in the page-table entry, including the access
permissions (AP) and memory region attributes TEX, cacheable (C) or bufferable (B) types are
examined in the next section.
Example: Generation of a Physical Address from a L1 Page Table Entry
Assume an L1 page table is placed at address 0x12300000. The processor core issues virtual address
0x00100000. The top 12 bits [31:20] define which 1 MB of virtual address space is being accessed.
In this case 0x001, so you need to read table entry [1]. Each entry is one word (4 bytes). To get the
offset into the table, you must multiply the entry number by entry size: 0x001 * 4 = address offset
of 0x004. The address of the entry is 0x12300000 + 0x004 = 0x12300004. So, upon receiving this
virtual address from the processor, the MMU reads the word from address 0x12300004.
X-Ref Target - Figure 3-5
Figure 3-5: L1 Page Table Entry Format
UG585_c3_06_070915
31
24
23
19 18 17 16 15 13
IGNORE
Page Table Base Address, bits [31:10]
Reserved
FaultPage TableSectionSupersectionReserved
Supersection Base Address PA[31:24]
Extended Base Address PA[35:32]
Domain
AP[2]
AP[1:0]
TEX[2:0]
Section Base
Address, PA [31:20]
0
0
SBZ
SBZ
NS
NS
XN C B
nG
Domain
14
12
11
10
9
8
7
6
5
43210
10
11
0
0
0
0S
Extended Base Address PA[39:36]
AP[2]
AP[1:0]
TEX[2:0]
0NS nG1S
1
20