3.3.4. Status Register

The Status Register characteristics are:

Purpose

Safely enables and disables snooping. When changing the snoop or DVM message enables using the Snoop Control Registers, see Snoop Control Registers, there is a delay until the changes are registered in all parts of the CCI-400. The change_pending bit in the Status Register indicates whether there are any changes to the enables that have not yet been applied, or whether a slave interface has been disabled for future snoop and DVM messages, but has outstanding AC requests.

Note

After changing the snoop and DVM enable bits, the controller must test that the change_pending bit is LOW before it turns an attached device on or off.

Usage constraints

There are no usage constraints.

Configurations

Available in all CCI-400 configurations.

Attributes

Table 3.5 shows the bit assignments.

Table 3.5. Status Register

BitsReset valueAccessFunction
[31:1]-RAZ/WIReserved
[0]0x0R/WI

Indicates whether any changes to the snoop or DVM enables is pending in the CCI-400:

0b0

No change pending.

0b1

Change pending.


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