A.6. Power management signals

Table A.9 shows power control interface signals.

Table A.9. Power control interface signals

NameI/O

Source or

Destination

Description

CPUCLAMP[N:0]

IPower controller

Interrupt interface clamps control signals:

CPUCLAMP[3] CPU3 interface

CPUCLAMP[2] CPU2 interface

CPUCLAMP[1] CPU1 interface

CPUCLAMP[0] CPU0 interface.

CPURAMCLAMP[N:0]

I

Enables the clamp cells in Dormant mode.

SCURAMCLAMP

I

Enables the SCU clamp cells in Dormant mode.

NEONCLAMP[N:0][a]

I

Activates the Cortex-A9 MPE SIMD logic clamps:0 = clamps not active1 = clamps active..

PWRCTLI0[1:0]I

Reset value for CPU0 status field (bits [1:0]) of SCU CPU Power Status Register[1:0].

PWRCTLI1[1:0]I

Reset value for CPU0 status field (bits [9:8]) of SCU CPU Power Status Register.

[9:8].

PWRCTLI2[1:0]I

Reset value for CPU0 status field (bits [17:16]) of SCU CPU Power Status Register.

[17:16].

PWRCTLI3[1:0]I

Reset value for CPU0 status field (bits [25:24]) of SCU CPU Power Status Register.

[25:24].

PWRCTLO0[1:0]O

b0x CPU0 must be powered on

b10 CPU0 can enter dormant mode

b11 CPU0 can enter powered-off mode.

PWRCTLO1[1:0]O

b0x CPU1 must be powered on

b10 CPU1 can enter dormant mode

b11 CPU1 can enter powered-off mode.

This signal exists only if CPU1 is present.

PWRCTLO2[1:0]OPower controller

b0x CPU2 must be powered on

b10 CPU2 can enter dormant mode

b11 CPU2 can enter powered-off mode.

This signal exists only if CPU2 is present.

PWRCTLO3[1:0]O

b0x CPU3 must be powered on

b10 CPU3 can enter dormant mode

b11 CPU3 can enter powered-off mode

This signal exists only if CPU3 is present.

SCUIDLEOPL310 or power controller

Indicates that the SCU is in IDLE state. This signal can be used to control clock or power-gating control signals of the modules connected to the SCU.

In the case of the PL310, the SCUIDLE output of the Cortex-A9 MPCore can be connected to the STOPCLK input of the PL310.

[a] Only if an MPE is present


See SCU CPU Power Status Register. See also Communication to the Power Management Controller.

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