A method for performing a secure boot of a data processing system, and the data processing system are provided. The method includes: processing a command issued from a processor of the data processing system, the command directed to a memory; determining that the command is a command that causes the memory to be modified; performing cryptographic verification of the memory; and incrementing a first counter in response to the determining that the command is a command that causes the memory to be modified. The data processing system includes a processor, a memory, and a counter. The memory is coupled to the processor, and the memory stores data used by a bootloader during a secure boot. The counter is incremented by a memory controller in response to a command being a type of command that modifies the data stored by the memory.