Offline MISR value calculation

[sandeepSingh18606]

I am currently working on the Flash Array Integrity implementation for the S32K312 controller.

According to the reference manual, the MISR value is calculated using a specific polynomial shown in below image. However, my offline calculated MISR values do not match the values generated in the User Mode (UM) registers even after multiple tries.

Upon further review, I noted that the MISR calculation occurs after ECC detection, and ECC parity cannot be calculated offline.

Could you please advise on the standard production-level approach for this implementation? Specifically, I would like to know:

1.  Is it possible to calculate expected MISR values offline and store them in Flash or NVM?
2.  Or is it necessary to run the code once to capture the calculated MISR value directly from the UM registers and save it for future checks?

Please guide me on the recommended strategy for a production-ready solution.

Best regards,
Sandeep Singh

[sandeepSingh18606]

Hi Daniel,

I have been receiving this same response for the past 7 to 8 months. I previously raised a ticket regarding this issue, and the response was identical to what I am receiving now. I also followed up with our NXP sales representative, but we still do not have a solution.

Could you please clarify if this functionality was tested by NXP and whether there is an active fix or workaround available for this issue?

I look forward to your prompt response.

Best regards,
Sandeep Singh

[danielmartynek]

Hi @sandeepSingh18606,

1. Let me check internally whether there has been any progress with the offline calculation.

I will get back to you as soon as possible.

2. This is an option. Here is an example: https://community.nxp.com/t5/S32K-Knowledge-Base/Example-S32K344-FLS-Integrity-Margin-Check-v1-0-S32...

BR, Daniel