3.2.13. Region Setup Low <n> Register

The region_setup_low_<n> Register characteristics are:

Purpose

None for region 0, for other regions it controls the base address [31:15] of region <n>.

Note

Base address [14:0] is always zero because the TZASC does not permit the region size to be less than 32KB.

Usage constraints

There are no usage constraints.

Configurations

Available in all configurations of the TZASC.

Attributes

See the register summary in Table 3.1.

Figure 3.13 shows the region_setup_low_<n> Register bit assignments.

Figure 3.13. region_setup_low_<n> Register bit assignments


Table 3.13 shows the region_setup_low_<n> Register bit assignments.

Table 3.13. region_setup_low_<n> Register bit assignments

BitsNameFunction
[31:15]base_address_low<n>

Controls the base address [31:15] of region <n> [a].

The TZASC only permits a region to start at address 0x0, or at a multiple of its region size. For example, if the size of a region is 512MB, and it is not at address 0x0, the only valid settings for this field are:

b0010 0000 0000 0000 0

b0100 0000 0000 0000 0

b0110 0000 0000 0000 0

b1000 0000 0000 0000 0

b1010 0000 0000 0000 0

b1100 0000 0000 0000 0

b1110 0000 0000 0000 0.

If you attempt to set an inappropriate base address for the size of the region, the TZASC ignores certain bits depending on the region size. See Table 3.16 for more information.

[14:0]-Reserved, SBZ.

[a] For region 0, this field is Read Only (RO). The TZASC sets the base address of region 0 to 0x0.


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