A.7. Power management signals

Table A.7 shows the power management signals.

Table A.7. Power management signals

NameTypeSource/destinationDescription
PWRCTLO0[1:0]OutputPower controllerReset value for processor 0 status field, bits[1:0] of SCU CPU Power Status Register.
PWRCTLO1[1:0][a]OutputReset value for processor 1 status field, bits[9:8] of SCU CPU Power Status Register.
SCUIDLEOutputL2C-310 or power controller

In the case of the L2C-310, the SCUIDLE output can be connected to the STOPCLK input of the L2C-310. Indicates the SCU is idle.

The SCU is idle when both processors are in WFI or in powerdown, and there is no pending transaction in the SCU on any of the AXI ports, that is, ACP, AXI master 0, AXI master 1, or AXI peripheral port.

Note

When using the ACP, even if there is no activity on the bus, the ACLKENSC input must remain HIGH, or must toggle at least once through HIGH, after the activity has stopped. If not, the SCUIDLE output cannot go HIGH.

[a] Only present if processor 1 is present.


See Power domains.

For SCU power management, see SCU CPU Power Status Register.

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