GICD_NSACR<n>E, Non-secure Access Control Registers, n = 0 - 63

The GICD_NSACR<n>E characteristics are:

Purpose

Enables Secure software to permit Non-secure software on a particular PE to create and control Group 0 interrupts.

Configuration

This register is present only when GICv3.1 is implemented. Otherwise, direct accesses to GICD_NSACR<n>E are RES0.

When GICD_TYPER.ESPI==0, these registers are RES0.

When GICD_TYPER.ESPI==1, the number of implemented GICD_ICFGR<n>E registers is ((GICD_TYPER.ESPI_range+1)*2). Registers are numbered from 0.

Attributes

GICD_NSACR<n>E is a 32-bit register.

Field descriptions

313029282726252423222120191817161514131211109876543210
NS_access15NS_access14NS_access13NS_access12NS_access11NS_access10NS_access9NS_access8NS_access7NS_access6NS_access5NS_access4NS_access3NS_access2NS_access1NS_access0

NS_access<x>, bits [2x+1:2x], for x = 15 to 0

Controls Non-secure access of the interrupt with ID 16n + x.

If the corresponding interrupt does not support configurable Non-secure access, the field is RAZ/WI.

Otherwise, the field is RW and determines the level of Non-secure control permitted if the interrupt is a Secure interrupt. If the interrupt is a Non-secure interrupt, this field is ignored.

The possible values of each 2-bit field are:

NS_access<x>Meaning
0b00

No Non-secure access is permitted to fields associated with the corresponding interrupt.

0b01

Non-secure read and write access is permitted to set-pending bits in GICD_ISPENDR<n>E associated with the corresponding interrupt. A Non-secure write access to GICD_SETSPI_NSR is permitted to set the pending state of the corresponding interrupt.

0b10

As 0b01, but adds Non-secure read and write access permission to fields associated with the corresponding interrupt in the GICD_ICPENDR<n>E registers. A Non-secure write access to GICD_CLRSPI_NSR is permitted to clear the pending state of the corresponding interrupt. Also adds Non-secure read access permission to fields associated with the corresponding interrupt in the GICD_ISACTIVER<n>E and GICD_ICACTIVER<n>E registers.

0b11

This encoding is treated as 0b10, but adds Non-secure read and write access permission to GICD_IROUTER<n>E fields associated with the corresponding interrupt.

The reset behavior of this field is:

Additional information

For interrupt ID m, when DIV and MOD are the integer division and modulo operations:

Accessing GICD_NSACR<n>E

GICD_NSACR<n>E can be accessed through the memory-mapped interfaces:

ComponentFrameOffsetInstance
GIC DistributorDist_base0x3600 + (4 * n)GICD_NSACR<n>E

This interface is accessible as follows:


26/03/2024 09:49; 67c0ae5282a7629ba0ea0ba7267b43cd4f7939f6

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