System executing a fast boot wake-up

Abstract

A processing system is set forth that includes a processor, read only memory storing an operating system image file accessible by the processor, and random access memory that is also accessible by the processor. The processing system also includes a boot program that is executable by the processor to initialize the processing system in response, for example, to a power-on event, reset event, or a wake-up event. A power-on event occurs when power is initially provided to the processing system while a wake-up event occurs when the processing system is to exit a low-power mode of operation. A reset event occurs when, for example, a fault is detected that causes the system to restart. The boot program selectively performs a full boot copy of the operating system image file from the read only memory to the random access memory or a fast boot copy of only predetermined portions of the operating system image file from the read only memory to the random access memory. For example, the boot program may execute the full boot copy operation in response to the power-on event and the fast boot copy operation in response to the wake-up event and/or reset event. Further, the boot program may limit execution of the fast boot copy operation to those instances in which the random access memory passes an integrity check of the contents of one or more areas containing selected portions of the operating system copied from the read only memory during a prior full boot copy operation.