TrustZone Address Space Controller (TZC-380) Technical Reference Manual: 3.2.2. Action Register

The action Register characteristics are:

Purpose: Controls the response signaling behavior of the TZASC to region permission failures.
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 3.3 shows the action Register bit assignments.

Figure 3.3. action Register bit assignments

Table 3.3 shows the action Register bit assignments.

Table 3.3. action Register bit assignments

Bits	Name	Function
[31:2]	-	Reserved, SBZ
[1:0]	reaction_value	Controls how the TZASC uses the bresps[1:0], rresps[1:0], and tzasc_int signals when a region permission failure occurs: b00 = sets tzasc_int LOW and issues an OKAY response b01 = sets tzasc_int LOW and issues a DECERR response b10 = sets tzasc_int HIGH and issues an OKAY response b11 = sets tzasc_int HIGH and issues a DECERR response.

Bits

Name

Function

[31:2]

Reserved, SBZ

[1:0]

reaction_value

Controls how the TZASC uses the bresps[1:0], rresps[1:0], and tzasc_int signals when a region permission failure occurs:

b00 = sets tzasc_int LOW and issues an OKAY response

b01 = sets tzasc_int LOW and issues a DECERR response

b10 = sets tzasc_int HIGH and issues an OKAY response

b11 = sets tzasc_int HIGH and issues a DECERR response.

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