OTPMK on iMX8QM

[matteo-facchinetti]

Is OTPMK burned to fuse by NXP in the i.MX8 and i.MX8Qx families?

[igorpadykov]

Hi Matteo

one can look on

https://community.nxp.com/t5/i-MX-Processors/OCOTP-write-support-on-i-mx8m/m-p/825028

https://imxdev.gitlab.io/tutorial/Burning_eFuses_on_i.MX8_and_i.MX8x_families/

Best regards
igor

[matteo-facchinetti]

Hi Igor,

thanks for the links but my doubt is about the "OTP Master Key" and where is stored.
From the RF, I don't find any reference to it in the fusemap.

The only documentation that I found is for iMX6 / iMX8M families.

From the iMX8QM_SRM:

The OTP Master Key (OTPMK) is a 256-bit secret value stored in one-time-programmable storage on
the SOC. The value is generally written to the one-time-programmable storage while the SOC is in the factory.

What does it mean for "...SoC is in the factory."? Is it burned by NXP before the SoC is shipped?

[igorpadykov · Accepted solution]

>my doubt is about the "OTP Master Key" and where is stored.

OTPMK is high security unique key, it is programmed in fuses during manufacturing process (on factory).

Due to security it is hidden from customers.

Best regards
igor