Patent attributes
Techniques in electronic systems, such as in systems including a processing chip and one or more external memory chips, provide improvements in one or more of system security (such as intrusion and/or virus/malware prevention), performance, cost, and efficiency. For example, the processing chip includes at least one CPU and circuitry enabling the at least one CPU to securely boot from an external, non-volatile memory chip containing encrypted, executable code, and does not expose un-encrypted data, including the executable code, on an external memory interface, including a DRAM interface. Further, only the specific processing chip that was used to initially write the encrypted executable code to the external non-volatile memory chip is able to decrypt the encrypted executable code. The decryption uses a key unique to the processing chip and created at manufacturing time that is never CPU-accessible, forming a secure hardware association between the two chips.