RE: Building standalone library without any TFM dependencies on nrf5340 TFM secure environment

Didrik Rokhaug — Thu, 23 Feb 2023 14:11:35 GMT

Hi,

Just to make sure I understood your question correctly:

You are developing a library, that will run in the non-secure domain, which uses some TF-M functionality. But, because you don't want to build a new library for each TF-M version, you do not want to depend on any TF-M symbols.

Does that accurately sum up your question?

If so, I would make a wrapper around the TF-M functionality that you use, and use the wrapper in the library. Then, you instruct the users how to implement the glue layer. This solution is similar to what we do for out modem library for the nRF9160. The library itself is OS agnostic, but requires some support from the OS/runtime, which means that the users of the modem library have to implement a glue layer between the library and the OS they are using.

You can see how we document this here: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/2.2.0/nrfxlib/nrf_modem/doc/ug_nrf_modem_porting_os.html#os-abstraction-layer

Best regards,

Didrik