Under construction…

i-boot (internal boot code) is stored in the chip's internal mask ROM. Upon power-on reset, when the system initializes, the program counters of all CPUs (four ARM Cortex A55) are set to point to the entry point address of the i-boot program. Once the power-on reset deasserts, the CPUs start executing from the entry point address of the i-boot program. i-boot first initializes the CPU, sets up all interrupt vectors, initializes the stack, initializes the cache, configures serial ports, sets timers, and more. After initialization, it loads x-boot from external storage devices into SRAM and executes it.

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