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.

Usage constraints

There are no usage constraints.

Configurations

Available in all CCI-400 configurations.

Attributes

Note

After writing to the snoop or DVM enable bits, the controller must wait for the register write to complete, then test that the change_pending bit is LOW before it turns an attached device on or off.

Figure 3.4 shows the bit assignments.

Figure 3.4. Status Register bit assignments

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Table 3.5 shows the bit assignments.

Table 3.5. Status Register bit assignments

Bits

Reset

Access

Function

[31:1]

-

RAZ/WI

Reserved.

[0]

0b0

R/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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