Could you please help review whether this process is feasible?
Option 1:
In the mass production stage, we first program the S32K3 chip with firmware that includes the HSE firmware installation, secure boot configuration, and the business logic binary. Next, we mount the S32K3 chip onto the PCB. Finally, after the chip has been mounted, we power on the S32K3 board and allow the firmware to complete the HSE firmware installation, secure boot configuration, and loading of the business logic binary. Once all these steps are completed, the board initializes HSE and secure boot, and the business logic runs as expected.
Option 2:
In the mass production stage, we first program the S32K chip with firmware containing a custom-developed bootloader capable of flashing firmware via CAN. Next, we mount the chip with the bootloader onto the PCB. On the next power cycle, the chip enters the bootloader. Using the bootloader, we then flash an application (App) that includes the HSE firmware, secure boot initialization, and the business logic binary loading. After flashing, we power up the board and let the App configure the HSE firmware and secure boot. On subsequent starts, the business logic binary will run as expected.
Please let us know if both options seem feasible. We are in communication with the production line, coordinating the programming method. Thank you very much for your response, and wishing you a pleasant day.
