[S32K388] BIST Prerequisite Details Clarifications Hi Team,
Customer is looking for some clarifications about information updated in latest version of the SAF/SPD Bist User Manual:
Looking into the newer version SAF BIST documentation, this is now the wording mentioned:
1) Is this an incorrect statement for the S32K388 device. Reading this as stated, it seems to imply that for the S32K388 it is recommended to run the BIST on CM7_0 core. This seems to be in stark contrast with what your device safety manual is suggesting that all safety checks should be running on the master safety core (AOU_SW_SAFETY_CORE_USAGE), and the master safety core is defined as CM7_2 core on the S32K388.
2) Can you address the below questions for clarification:
Is it mandatory that the cores that the BIST is NOT executing on are "disabled", or just a recommendation?
Does "disabled" here mean the cores are literally halted in hardware and are not at all executing, or if they are simply in a software wait loop with all interrupts disabled and waiting for the BIST to be completed good enough?
If it really needs to be halted in hardware, does this effectively exclude the option for me to enable those cores to start automatically through the IVT boot configuration word, and instead have to keep those cores off until after the BIST has executed (and I'd have to develop a software strategy for manually starting the other cores)?
Thanks, Daniel V. Safety_SW Re: [S32K388] BIST Prerequisite Details Clarifications Hello Daniel, customer is right about what is master safety core on K388, it will be fixed in BIST UM. As per Safety architects, it doesn't necessarily mean it must be CM7_2, if customer wants to run ASIL_D on CM7_0, and has K388_LS chip variant it is possible to consider CM7_0 as master safety core and run SAF from that core.
Second question is HW related, but simple answer is to keep the other cores in reset, which should be default state. Typically which cores are enabled is set in startup in Boot Configuration Word as customer mentioned, so yes to run online BIST on K3 requires to run the other cores after BIST within customer SW - I think using MCU driver via Mcu_SetMode().
It's a good question whether it should be enough to put the other cores into SleepMode or some loop where it will do nothing, but this use case is not validated - HW team need to confirm. My understanding is that BIST is accessing some HW and Memories which can be used by other cores (check RM e.g. for instruction and data cache blocks covered be MBIST) if there would be some app running so it would corrupt correct BIST execution.
Kind Regards, Radoslav
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