Providing a trustworthy indication of the current state of a multi-processor data processing apparatus
AssigneeArm Limited
InventorJohn David MERSH
Life of this patent
Estimating the term…
Abstract
A data processing apparatus formed on an integrated circuit comprising: a plurality of processors; power control circuitry configured to control power up and power down of the processors; a read only memory for storing boot up software for booting up each of the processors. The power control circuitry is configured to respond to receipt of a check state request, to control one of the processors that is currently powered down to power up and to access the boot up software. The boot up software accessed in response to the check state request controls the processor to perform a measurement indicative of a current state of the data processing apparatus and to output a value indicative of the measurement.
Claims20
A data processing apparatus formed on an integrated circuit comprising:
- a plurality of processors;
- power control circuitry configured to control power up and power down of said plurality of processors;
- a read only memory for storing boot up software for booting up each of said plurality of processors;
- wherein
- said power control circuitry is configured to respond to receipt of a check state request, to control one of said plurality of processors that is currently powered down to power up and to access said boot up software, said boot up software accessed in response to said check state request controlling said processor to perform a measurement indicative of a current state of said data processing apparatus and to output a value indicative of said measurement.
A method of checking a state of a data processing apparatus formed on an integrated circuit comprising a plurality of processors, said method comprising:
- receiving a check state request;
- powering up one of said plurality of processors that is currently powered down;
- accessing and executing boot up software;
- performing a measurement indicative of a current state of said data processing apparatus under control of said boot up software running on said processor that is powering up;
- and
- outputting a value indicative of said measurement.
A data processing apparatus formed on an integrated circuit comprising:
- a plurality of processing means for processing data;
- power control circuitry configured to control power up and power down of said plurality of processing means;
- a read only memory means for storing boot up software for booting up each of said plurality of processing means;
- wherein
- said power control means is for controlling one of said plurality of processing means that is currently powered down to power up in response to receipt of a check state request, and to access said boot up software, said boot up software accessed in response to said check state request controlling said processing means to perform at least some initialising functions and to perform a measurement indicative of a current state of said data processing apparatus and to output a value indicative of said measurement.
Dependencies are inferred from the claim text.