Unable to connect to target I.MX8MPLUS

Hi

My name is Stephen and I work at Arm.

It looks like you are trying to use the Platform Configuration Editor (PCE) auto-detection feature.
Arm DS has a ready-made debug configuration for the NXP i.MX8Mplus, so there is no need to use the PCE auto-detection feature.

To access the ready-made debug configuration for the NXP i.MX8Mplus, use 
Run > Debug Configurations, select Generic Arm C/C++ Application > New launch configuration.  In the filter, enter "i.MX8Mplus".
See screenshot.



"Unable to connect to device ARMCS-DP" means the debugger is not able to the CoreSight Debug Port.  This might be because it is not powered-up.  The NXP i.MX8Mplus has quite a complex power-up/start-up sequence, requiring the Cortex-M7 to run some code to power-up the Cortex-A53s.  When booting into Linux, this is normally all done for you, so try booting into Linux first, and then connecting.

If that still doesn't work, try lowering the JTAG clock frequency.

If your target has booted into Linux, but you still can't connect, perhaps Linux has turned off the debug clocks in order to save power.  Try power-cycling the target, and halting it at the (u)boot prompt, then try reconnecting.

Which debug probe are you using - e.g. a DSTREAM-ST?

Hope this helps

Stephen

We are using DSTREAM-ST for 8MPLUSLPD4-EVK board.

In debug configuration we are able to detect DSTREAM-ST and selected I.MX8MPLUS EVK in baremetal selected cortex M7. We tried by changing different frequencies but getting the same error as shown in the below snippet. We followed the procedure you have mentioned.

In debugging tab we enabled Connect only  after that clicked on debug. We are getting failed to connect to any devices on the target. Check that the target is correctly connected to the debug probe and powered on. 

The board is working because it is booting from EMMC Flash. can you guide us to debug through JTAG for the 8MPLUSLPD4-EVK.

Thanks & Regards,

K.Bhardwaj

Hi again

I'm not very familiar with the i.MX8Mplus, but the board documentation "Getting Started with MCUXpresso SDK for EVK-MIMX8MP.pdf" says:

>For the security reason, only after the U-Boot is boot up, the JTAG can be allowed to connect to M core.

Is your board booting into Linux?  If not, I think you'll need to (at least start the) boot into Linux:
1) Prepare a microSD card with a Linux image
2) Connect a serial terminal emulator such as PuTTY to the COM port (as shown in the guide above)
3) Power up the board and hit a key on the U-Boot start

Also, check pin JTAG_MOD.  Some users on the NXP Community have reported related issues there.  See e.g.

https://community.nxp.com/t5/i-MX-Processors/I-MX8M-Plus-Enter-JTAG-Debug/m-p/1577793

and

https://community.nxp.com/t5/i-MX-Processors/iMX8M-Plus-Cortex-M7-JTAG-Debug-quot-Could-not-measure-IR-len/td-p/1660528

Hope this helps

Stephen

Hi Stephen,

We connected the USB-UART port in I.MX8MPLUS to PC(Windows) and connected to putty. In U-Boot we stopped the booting then we did debug in arm development studio using DStream-ST jtag. Still we are getting the same error. 

Hi again

Sorry, I meant to add:
After interrupting u-boot, issue this command:

u-boot=> bootaux 0x7e0000
## Starting auxiliary core stack = 0xEDFE0DD0, pc = 0x28040000...

In our tests (with an early board/distro) we also needed to issue this command, but sorry, I don't know whether it will be needed for your setup, or whether the values might need to be different:
u-boot=> md.w 0x30340058 0xFFFFFFFE

For more information see section 4.7.4.1.2 of

www.nxp.com/.../UG10163.pdf

If you still need more help, I suggest you reach out to the NXP Community at

https://community.nxp.com/

who are best placed to advise on the specifics of their board boot,
or "Open a Support Case" with Arm using the Support link at the bottom of this page.

Stephen