Getting to Apalis IMX8 M4_0 & M4_1 debug Uarts on Ixora carrier?

I’ve got Apalis IMX8 on an Ixora carrier and I’m trying to run up FreeRTOS on it.

But I haven’t yet been able to figure out how to connect to the M4 tightly coupled uarts.

Plus, this article

suggests that the released Uboot will have a conflict and needs to reconfigured first.

Any thoughts are most welcome.

Unfortunately Ixora board does not support tightly coupled UARTs

You need to use Apalis Evaluation board to have access to both M4 UARTs. Please check this article

U_Boot has no conflicts with tightly coupled UARTs however Linux may have it depending on Device Tree configuration,

Thanks Alex. Is there another recommended way to debug the M4 cores on Ixora, other than writing to shared mem and hoping for the best.

It’s possible to debug M4 using a JTAG but Ixora board has no JTAG connector as well. Only an Apalis Evaluation board has it. So if you limited by Ixora only you either need to use RPMSG or use a one of the “regular” UARTs. The last approach is more complicated since you need to properly setup pinmuxing and program Domain Recourse Controller.

Thanks Alex. I understand about RPMSG.
Where can I find a guide to the pin-muxing the DRC ?

Is this still true for V1.2A of the Ixora board?
I’m not able to get the tightly coupled uarts to work.

Yes, same is true for Ixora v1.2A as well.