ncs2.6.0 matter has Failed to reboot error.

[zero]

Dear support team,
The customer used ncs2.6.0 to run on nRF52840 to make matter over thread smart door lock. When stress testing the switch lock (repeat: password unlock (the switch lock will control the motor, serial port communication, matter reports the lock status and power)--automatic lock), the program log output the following content:

00> 0?D?h

00>  _???Ho?(??F Fl?z?m?
00> ?m?i?m?g?S ?? ??^??? ???
HD?M?%?]?? ???
xJ???0?y?? Jh??
z??0K???0?h?
F??? F???[???F? ??
?`??????????o?H???@?IH?"3???!H3??H???,h?B?4? F????+?+?
+?9h
h??h?Gd+?"?!?????!0F???u?#??,(:?,3,'??j?GpG???h
00> F
?!F?G?}?h
;??u"???@G?`????8?F
00> FK?@n???H? n)F??8@??V???8@?%?8?0?F??FF??,?FP?O?$S????)F(F? m? ?? ? 1? ?? ?? ?? ? ? ? ? ! endlessly...
00> B?`,ii?n?_?\??ZZn????N??"

By searching ncs, only "Failed to reboot: spinning endlessly..." was found in the sys_reboot function

Why did sys_reboot fail? What are the reasons for failure?

BR，

Zero

[Susheel Nuguru]

I have never seen this before or heard that someone hit this in their code on nRF code.

1. Did you get into sys_arch_reboot and see if it is executing nRF related reboot code?
2. Are you running a debugger while this is happening?
3. Is this a custom device or can you reproduce this on the nRF52840 DK?
4. If this is a custom board, are you sure the external clocks are working ok?

If you can help me reproduce it, I can try to understand why reset did not work for you.

[zero]

Hi

Please help make this case private.

Susheel Nuguru said:

Did you get into sys_arch_reboot and see if it is executing nRF related reboot code?

The probability of reproducing this problem is extremely low, and it is difficult to debug to see if it is executing the restart code related to nRF.

Susheel Nuguru said:

Are you running a debugger while this is happening?

No.

Susheel Nuguru said:

Is this a custom device or can you reproduce this on the nRF52840 DK?

Yes, this is a customer-customized device, but the customer application code does not execute sys_reboot; it cannot be reproduced on the dk at present.

Susheel Nuguru said:

If this is a custom board, are you sure the external clocks are working ok?

Yes, the customer tested more than 6000 times and there were 2 such errors.

BR,

Zero

[Susheel Nuguru]

Do you have any external flash or have enabled CONFIG_SPI_NOR as shown in this thread?

[zero]

Hi

Check the matter mcuboot does not start CONFIG_SPI_NOR.

BR，

Zero

[Susheel Nuguru]

Zero,

zero said:

Yes, this is a customer-customized device, but the customer application code does not execute sys_reboot; it cannot be reproduced on the dk at present.

I would recommend you to connect the debugger, put a breakpoint in sys_arch_reboot and step into it to see if the it is executing the NVIC_SystemReset command for the nRF52. 

Other thing I would recommend to try is to put 100ms delay in front of sys_arch_reboot to see if that helps. If it does, then there is either some ongoing flash activity or some other clock issues on your custom board. 

It is hard to narrow down the problem from my end without being able to reproduce it on DK and not having your hardware with me.