Abstract: Circuits and methods for power dependent selection of boot images are disclosed. In an example implementation, an apparatus includes a memory circuit and a processor disposed on an integrated circuit die. The processor is configured to retrieve and execute instructions from the memory circuit. The apparatus also includes a power management circuit configured to determine a value indicative of an amount of power available to power the IC die. A boot loader circuit is coupled to the power management circuit and is configured to select one of a plurality of boot images based on the determined value indicative of the amount of power available. The boot loader circuit loads a set of instructions included in the selected one of the boot images into the memory circuit and enables the processor to execute the set of instructions.

Abstract: In some disclosed implementations, a system-on-chip on a first IC die includes a boot loader circuit configured to search a first boot device, of a plurality of boot devices coupled to and external to the first IC die, for an uncorrupt boot image. The boot loader circuit is configured to search a second boot device of the plurality of boot devices for an uncorrupt boot image, in response to failing to find an uncorrupt boot image in the first boot device. The boot loader is also configured to load a set of instructions included in the uncorrupt boot image into a memory circuit of the SOC, in response to finding an uncorrupt boot image.

Abstract: A method includes initiating a boot of a system-on-chip coupled to a boot device. The boot is initiated from boot code stored in nonvolatile memory responsive to a power-on-reset. Under control of the boot code: a first register value is loaded into a register; a name string from the boot code is accessed; the first register value is obtained from the register; and the first register value and name string are converted to a first string value, which is provided as a first filename. The boot device is searched for a boot image file with the first filename. If the first filename is not found in the boot device, the first register value is incremented to provide a second register value. The obtaining, converting, and searching are repeated using a second filename generated using the second register value, and a valid filename for the boot image file is iteratively generated.

Abstract: A system generally relating to an SoC, which may be a field programmable SoC (“FPSoC”), is disclosed. In this SoC, dedicated hardware includes a processing unit, a first internal memory, a second internal memory, an authentication engine, and a decryption engine. A storage device is coupled to the SoC. The storage device has access to a boot image. The first internal memory has boot code stored therein. The boot code is for a secure boot of the SoC. The boot code is configured to cause the processing unit to control the secure boot.

Abstract: A method relating generally to loading a boot image is disclosed. In such a method, a header of a boot image file is read by boot code executed by a system-on-chip. It is determined whether the header read has an authentication certificate. If the header has the authentication certificate, authenticity of the header is verified with the first authentication certificate. It is determined whether the header is encrypted. If the header is encrypted, the header is decrypted.

Abstract: A method relating generally to generating a boot image, as performed by an information handling system, for an embedded device is disclosed. This method includes a public key obtained by a boot image generator. A first hash for the public key is generated by the boot image generator. The first hash is provided to a signature generator. A first signature for the first hash is generated by the signature generator. A first partition for the boot image is obtained by the boot image generator. A second hash for the first partition is generated by the boot image generator. The second hash is provided to the signature generator. A second signature for the second hash is generated by the signature generator. The boot image generator and the signature generator are programmed into the information handling system. The boot image includes the public key, the first signature, and the second signature. The boot image is output from the information handling system.