3.2.3. Lockdown Range Register

The lockdown_range Register characteristics are:


Controls the range of regions that are locked down.

Usage constraints

The lockdown_select Register can restrict the access type of this register to RO. See Lockdown Select Register.


Available in all configurations of the TZASC.


See the register summary in Table 3.1.

Figure 3.4 shows the lockdown_range Register bit assignments.

Figure 3.4. lockdown_range Register bit assignments

Table 3.4 shows the lockdown_range Register bit assignments.

Table 3.4. lockdown_range Register bit assignments


When set to 1, it enables the lockdown_regions field to control the regions that are to be locked


Reserved, SBZ



Controls the number of regions to lockdown when the enable bit is set to 1:

b0000 = region no_of_regions [a]-1 is locked

b0001 = region no_of_regions-1 to region no_of_regions-2 are locked

b0010 = region no_of_regions-1 to region no_of_regions-3 are locked

b0011 = region no_of_regions-1 to region no_of_regions-4 are locked




b1111 = region no_of_regions-1 to region no_of_regions-16 are locked.

[a] no_of_regions is the value of the no_of_regions field in the configuration Register. See Configuration Register.

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