VAR-3P-SOM-AM62: Difference between MCU + SDK and Linux SDK

Hi Zain,

Different cores (A53, M4F, R5F) can run different operating systems, so TI has different SDKs for the various operating systems.

The Linux SDK is for running Linux on A53 cores on the device. The MCU+ SDK mostly supports noRTOS/freeRTOS for the M4F and R5F cores (and experimental feature of RTOS on A53).

From a software development point of view, there are two different teams that work on the two SDKs, but the release schedules are aligned.

Best Regards,

Anshu

Anshu,

I would avoid suggesting use of FreeRTOS on the 64 bit A53 cores. Knowing that the Linux community is looking forward to having products using "Linux as an RTOS" in the future (see Toravalds interview https://www.zdnet.com/article/20-years-later-real-time-linux-makes-it-to-the-kernel-really/ ) I would suggest TI steer away from mainline support of A53 FreeRTOS (I started a conversation with TIer Nick Saulnier about real time Linux future notions).

later

Jim Mrowca

(exTIer 1982-1997)

Hi Jim,

Thanks for the note.

For future readers, there are still multiple contexts where a usecase may want FreeRTOS, AutoSAR, QNX, etc running on a processor core instead of Linux. RT Linux getting fully added to upstream Linux is great, because it means that RT Linux will continue to be around and supported for many years to come. However, RT Linux getting upstreamed does NOT mean that other operating systems are no longer useful.

To provide a bit more context:

RT Linux is NOT a true real-time operating system (RTOS). RT Linux is much more deterministic than regular Linux, but it does NOT provide the same level of determinism as a true RTOS. Also, in general RT Linux will have a slower response time than a true RTOS.

Here is an easy question that system designers can ask themselves: If your software misses your timing requirements once a week, or once a year, is that ok? Or will that potentially kill someone, damage your factory equipment, or lead to some other unacceptable outcome?

If your system is tolerant to occasional missed timings, then RT Linux may be a good fit. However, if you absolutely MUST make your timing requirements 100% of the time, every time, for many years of service, then TI does NOT suggest putting RT Linux within that critical control path.

For example, you could use Linux running on the AM62x A53 cores to drive a display for a medical device. If the display updates 1 millisecond late, that is ok. But I would NOT use code running on RT Linux to keep someone alive - that is better for a true RTOS that has been specifically designed for the usecase.

Regards,

Nick