Patent ID: 8838924

Claim:
An apparatus providing for a secure execution environment, comprising: a microprocessor, coupled to a system bus, configured to execute non-secure application programs and a secure application program, wherein said non-secure application programs are accessed from a system memory via said system bus, and wherein said microprocessor is also configured to automatically transition to a degraded mode where only BIOS instructions are allowed to execute in order to allow for user input and the display of messages, said microprocessor comprising: a non-secure memory, configured to store portions of said non-secure application programs for execution by the microprocessor, wherein said non-secure memory is observable and accessible by said non-secure application programs and by system bus resources within said microprocessor; a secure volatile memory, configured to store said secure application program for execution by said microprocessor, wherein said secure volatile memory is isolated from said non-secure application programs and said system bus resources within said microprocessor, and wherein said secure application program is retrieved from a secure non-volatile memory over a private bus, decrypted using a processor unique key, and is written to said secure volatile memory; a cryptographic unit, isolated from said system bus and disposed within execution logic in said microprocessor, configured to employ said processor unique key to decrypt said secure application program; and a processor key register, coupled to said cryptographic unit, configured to store said processor unique key, wherein said processor key register can only be read by said cryptographic unit.