Migrating from FreeRTOS to SafeRTOS on S32K34x

[abhishekpeak]

We are currently using FreeRTOS in our code base and are migrating to SafeRTOS on #S32K3x

Our code (with FreeRTOS) currently uses USING_OS_FREERTOS configuration for the OSIF layer. This allows the MCAL drivers to use different interrupt masking strategies based on context (BASEPRI in ISRs to allow higher-priority interrupts vs. PRIMASK in tasks). There is no official support for SafeRTOS while configuring the RTD/MCAL in S32 design studio, so either the option is to use the FreeRTOS or to use the bare metal approach. Configuring the NXP RTD OSIF layer with USING_OS_BAREMETAL, causes MCAL critical sections to use direct assembly instructions (cpsid i/cpsie i) without RTOS integration.

I am wondering what the best approach is. Using:

- BAREMETAL mode with manual interrupt management.
- FREERTOS with some kind of compatibility layer or changing the OSIF code for RTOS-aware critical sections.
- A native SafeRTOS integration approach (if there is one).

[Julián_AragónM]

Hi @abhishekpeak.,

You are correct, right now there is no native SafeRTOS integration approach, and as far as I know, we have no plan to provide it for customer use. NXP mainly focuses on the RTD driver which support MCAL layer in AUTOSAR. It is customer's willingness to select third-party RTOS, stacks, IDEs, compilers, etc. for their project.

Realistically, you could implement either approach for this, either baremetal or starting with FreeRTOS and eventually upgrading to SafeRTOS.

I found this document regarding scalability and the S32K family: S32K_SAFERTOS_Datasheet_v1.1.pdf.

Of course, this means that integration should be done with the support of a third-party.

Just as a note, you can also refer to S32K3 - NXP RTOS. The NXP RTOS is a real-time operating system which conforms to the AUTOSAR Specification of Operating System R21-11 rev. 0 specification. Since it is delivered by NXP, it is aligned with the RTD releases.

Best regards,
Julián