Systems and methods for secure boot ROM patch

摘要

A data processing system includes a boot read only memory (ROM) configured to store boot code; one time programmable (OTP) storage circuitry configured to store patch instructions; a random access memory (RAM); and a processor coupled to the boot ROM, the OTP storage circuitry, and the RAM. The processor is configured to: in response to a reset of the data processing system, copy one or more patch instructions from the OTP storage circuitry into the RAM, and during execution of the boot code, execute a patch instruction from the RAM in place of a boot instruction of the boot code.

主权项

1. A data processing system comprising:
a boot read only memory (ROM) configured to store boot code; one time programmable (OTP) storage circuitry configured to store patch instructions; a random access memory (RAM); a processor coupled to the boot ROM, the OTP storage circuitry, and the RAM, and configured to:
in response to a reset of the data processing system, copy one or more patch instructions from the OTP storage circuitry into the RAM, andduring execution of the boot code, execute one or more of the patch instructions from the RAM in place of a boot instruction of the boot code; and a ROM controller coupled to the ROM, wherein the OTP is configured to store ROM controller configuration data, and the processor is further configured to:
in response to the reset of the data processing system, use the ROM controller configuration data to configure the ROM controller, wherein the ROM controller configuration data indicates a location in the RAM of the patch instruction; and storage circuitry configured to store a ROM lock bit, wherein the processor is configured to assert the ROM lock bit after the one or more patch instructions are copied from the OTP storage circuitry into the RAM.