ARM ARM1176JZF-S - Figure 3-34 Translation Table Base Control Register Format; Table 3-57 Translation Table Base Control Register Bit Functions

System Control Coprocessor
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Table 3-57 lists the purposes of the individual bits in the Translation Table Base Control
Register.
The Translation Table Base Control Register is:
•in CP15 c2
• a 32 bit read/write register banked for Secure and Non-secure worlds
• accessible in privileged modes only.
Figure 3-34 shows the bit arrangement for the Translation Table Base Register 1.
Figure 3-34 Translation Table Base Control Register format
Table 3-57 lists how the bit values correspond with the Translation Table Base Register 0
functions.
Attempts to write to this register in Secure Privileged mode when CP15SDISABLE is HIGH
result in an Undefined exception, see TrustZone write access disable on page 2-9.
P
D
1
P
D
0
S
B
Z
UNP/SBZ
31 32 0
N
456
Table 3-57 Translation Table Base Control Register bit functions
Bits Field name Function
[31:6] - UNP/SBZ.
[5] PD1 Specifies occurrence of a page table walk on a TLB miss when using Translation Table Base
Register 1. When page table walk is disabled, a Section Fault occurs instead on a TLB miss:
0 = The processor performs a page table walk on a TLB miss, with Secure or Non-secure
privilege appropriate to the current world. This is the reset value
1 = The processor does not perform a page table walk. If a TLB miss occurs with Translation
Table Base Register 1 in use, the processor returns a Section Translation Fault.
[4] PD0 Specifies occurrence of a page table walk on a TLB miss when using Translation Table Base
Register 0. When page table walk is disabled, a Section Fault occurs instead on a TLB miss:
0 = The processor performs a page table walk on a TLB miss, with Secure or Non-secure
privilege appropriate to the current world. This is the reset value
1 = The processor does not perform a page table walk. If a TLB miss occurs with Translation
Table Base Register 0 in use, the processor returns a Section Translation Fault.
[3] - UNP/SBZ.
[2:0] N Specifies the boundary size of Translation Table Base Register 0:
b000 = 16KB, reset value
b001 = 8KB
b010 = 4KB
b011 = 2KB
b100 = 1KB
b101 = 512-byte
b110 = 256-byte
b111 = 128-byte.