Apparatus and power-saving method for controlling a return to a normal power mode

A method of power-save control for an information processing apparatus having a main storage device and at least one primary processor the information processing apparatus shift-able to a power-save mode continuing power supply to the main storage device while power supply to the at least one primary processor, the method comprising:

• storing operation status information indicating operation status of the at least one primary processor in the main storage device when shifting to the power-save mode;
• storing storing-destination information indicating a storage area of the operation status information in the main storage device to a secondary storage device;
• stopping power supply to the at least one primary processor after storing the operation status information and the storing-destination information;
• confirming return operation identification information set by at least one secondary processor that detects a return-initiating event for returning from the power-save mode when conducting initialization process of the at least one primary processor after supplying power to the at least one primary processor;
• obtaining first present time information when shifting to the power-save mode, and storing the first present time information in the main storage device or the secondary storage device;
• obtaining second present time information when the operation status information is read out and the at least one primary processor is restored;
• computing an elapsed time between the first present time and the second present time;
• determining completion status information regarding a plurality of timer processings;
• using the computed elapsed time for the uncompleted timer processing of the plurality of timer processings based on the results of the determination;
• and
• reading out the operation status information by referring the storing-destination information stored in the secondary storage device when the return operation identification information is confirmed.

A non-transitory computer-readable storage medium storing a program that, when executed by a computer, causes the computer to execute a method of power-save control for an information processing apparatus having a main storage device and at least one primary processor, the information processing apparatus shift-able to a power-save mode continuing power supply to the main storage device while stopping power supply to the at least one primary processor, the method comprising:

• storing operation status information indicating operation status of the at least one primary processor in the main storage device when shifting to the power-save mode;
• storing storing-destination information indicating a storage area of the operation status information in the main storage device to a secondary storage device;
• stopping power supply to the at least one primary processor after storing the operation status information and the storing-destination information;
• confirming return operation identification information set by at least one secondary processor that detects a return-initiating event for returning from the power-save mode when conducting initialization process of the at least one primary processor after supplying power to the at least one primary processor;
• obtaining first present time information when shifting to the power-save mode, and storing the first present time information in the main storage device or the secondary storage device;
• obtaining second present time information when the operation status information is read out and the at least one primary processor is restored;
• computing an elapsed time between the first present time and the second present time;
• determining completion status information regarding a plurality of timer processings;
• using the computed elapsed time for the uncompleted timer processing of the plurality of timer processings based on the results of the determination;
• and
• reading out the operation status information by referring the storing-destination information stored in the secondary storage device when the return operation identification information is confirmed.