Entropy source is not available

Hi Sir/Madam,
I’m trying to port mbedtls version from 2.27.0 to 3.4.1.
previously we have utilized NULL entropy source which is not featured in version 3.4.1, we are using QNX and in target which we are using won’t support the below available entropy source.

Platform entropy, Hardware entropy and Nv seed.
So please suggest any alternative entropy source for NULL entropy or dummy which can be supported in QNX and NXP imx8 soc.

Thanks and Regards
Hema Srinivasan