Power Control Sources; Power-Up Sequence; Power-Down Sequence; System Reset Control - Intel SE7520JR2 Technical Manual

Platform Management
5.3.2

Power Control Sources

The sources listed in the following table can initiate power-up and/or power-down activity.
Source
Power button
mBMC Watchdog Timer
Platform Event Filtering
Command
Power state retention
5.3.3

Power-up Sequence

When turning on the system power after one of the event occurrences, the mBMC executes the
following procedure:
1. The mBMC asserts Power Supply (PS) Power On via the chipset and waits for the
power subsystem to assert Power Good. The system is reset.
2. The mBMC initializes all sensors to their Power On initialization states. The Init
Agent is run.
3. The mBMC attempts to boot the system by running the FRB algorithm, if FRB is
enabled.
5.3.4

Power-down Sequence

To power down the system, the mBMC effectively performs the sequence of power-up steps in
reverse order. It occur as follows:
1. The mBMC asserts system reset.
2. The mBMC de-asserts the Power On signal via the chipset.
3. The power subsystem turns off system power upon de-assertion of the Power On
signal.
5.3.5

System Reset Control

5.3.5.1

Reset Signal Output

The mBMC asserts the System Reset signal on the baseboard to perform a system reset. The
mBMC asserts the System Reset signal before powering the system up. After power is stable as
indicated by the power subsystem Power Good signal, the mBMC sets the processor enable
state as appropriate and de-asserts the System Reset signal, taking the system out of reset.
The system reset signal responds to the control panel or IPMI commands.
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Table 47: Power Control Initiators

External Signal Name or
Internal Subsystem
Front control power button
Internal mBMC timer
PEF
Routed through command processor
Implemented via mBMC internal logic
C78844-002
Intel® Server Board SE7520JR2
Capabilities
Turns power on or off
Turns power off or power cycle
Turns power off or power cycle
Turns power on or off, or power cycle
Turns power on when AC power returns
Revision 1.0