Patent ID: 8151028

Claim:
An information processing apparatus connected with an IO device, comprising: a processing unit; a channel device connected to the IO device and to the processing unit through a system controller and configured to transfer data between the information processing apparatus and the IO device; a storage device connected to the processing unit and the channel device through the system controller and having a predetermined area for storing a result of an operation executed by the channel device and information indicating a request from the channel device to the processing unit; an interrupt controller incorporated in the channel device and configured to control an interrupt requested by the channel device to the processing unit; a channel device controller configured to control the channel device; a driver incorporated in the processing unit; and an activation controller configured to activate the channel device according to a command issued by the driver, read information stored in the predetermined area, and transfer the read information to the channel device controller, wherein the processing unit writes activation information used for activating the channel device into the predetermined area of the storage device and sends a command for activation to the channel device, and the channel device reads the information stored in the predetermined area when the command is received, executes an activation operation, and writes a result of the activation operation into the predetermined area and sends an interrupt to the processing device upon completion of the activation operation.