Best way to isolate a core on Verdin iMX8M

Hi,

I am using a Toradex Verdin iMX8M Plus Quad 4GB Wi-Fi / BT IT V1.0D on a Toradex Verdin Development Board V1.1D and am looking to isolate one of the Cortex A53 processors from the kernel to be used for real time DSP.

I have been attempting to use the isolcpus kernel command line option, but as of yet I have been unable to determine where/how I set this parameter.

I am hoping someone will be able to give me some advice regarding this configuration, as well as any info on other methods of achieving the same outcome, should they be preferred.

I am using TorizonCore with PREEMPT_RT 5.7.0+build.17 verdin-imx8mp-07154614 ttymxc2

Regards,
Neil

Greetings @Neil_M,

I’m not very familiar with the isolcpus kernel option, but I’ll provide what advice i can. So starting off you said:

I have been attempting to use the isolcpus kernel command line option, but as of yet I have been unable to determine where/how I set this parameter.

How exactly have you been trying to apply this option so far?

Best Regards,
Jeremias

Hi @jeremias.tx

Thanks for your quick response.

I have been able to achieve the outcome I was after using torizon core builder.

This article provided me with the information I was looking for.

I adjusted the tcbuild.yaml file to include my custom kernel arguments and built a custom image from that. After loading the custom image, I have confirmed the core I set has indeed been isolated.

Thanks again,
Neil

Personally, I would like to see you provide a touch more detail on this than

“Hey! I got it to work!”

I’m sure it will come up again as more of these processors become capable enough for DSP.

Glad you were able to find the solution!

Hey @seasoned_geek

I’m sorry you feel that way, but believe I provided more in my response than simply “Hey! I got it to work!”.

I have provided the tool I used, the files I adjusted and a link to an article instructing you how to achieve the same outcome.

If you are trying to achieve something similar and are having trouble, feel free to send me a message and I would be happy to help out where I can.

No, I’m not trying to do this myself, but you should include at least the section where you added your custom kernel arguments to this for completeness. The next poor schmoe to stumble onto this will probably be a first timer and having that snippet in the thread can save them days of trying to find you or get someone else to explain it. I was only following this because it sounded like something that might come up for me in the future.

I definitely appreciate what you’re saying as, many times in the past I have been that first timer trying to figure something out.

This is exactly why I included the link to “Customizing Kernel Arguments in Torizon”, which I believe provides all the info someone would need to achieve the same thing I have (including where to add the custom kernel arguments).

Torizon links move. That’s the problem with using them in these threads. Yeah, it works today, but a few months from now it won’t.