Possible SPI bug in SDK v2.6 ?

[Cambridge_dev]

I'm having problem with SPI devices using nRF Connect SDK 2.6 with a 9160DK. Following lesson 5 in the intermediate course I get BUS FAULTS when the application starts. 

Setup

1. nRF Connect SDK 2.6.0
2. Hardware nRF 9160DK
3. Application inter_less5_exer1_solution
4. Build for board nrf9160dk_nrf9160_ns
5. Flashing to the DK gives this output on the console:

[00:00:00.419,189] <err> os: ***** BUS FAULT *****
[00:00:00.419,219] <err> os: Precise data bus error
[00:00:00.419,219] <err> os: BFAR Address: 0x0
[00:00:00.419,250] <err> os: r0/a1: 0x00020890 r1/a2: 0x00020548 r2/a3: 0x000151f0
[00:00:00.419,250] <err> os: r3/a4: 0x40009000 r12/ip: 0x00000000 r14/lr: 0x0001d571
[00:00:00.419,281] <err> os: xpsr: 0x81000000
[00:00:00.419,281] <err> os: Faulting instruction address (r15/pc): 0x00015288
[00:00:00.419,311] <err> os: >>> ZEPHYR FATAL ERROR 25: Unknown error on CPU 0
[00:00:00.419,372] <err> os: Current thread: 0x2000cdf0 (main)
[00:00:00.481,811] <err> os: Halting system

The PC points to /opt/nordic/ncs/v2.6.0/zephyr/drivers/pinctrl/pinctrl_nrf.c:138 and r14 points to /opt/nordic/ncs/v2.6.0/zephyr/include/zephyr/drivers/pinctrl.h:354

Since the app never reaches main() I'm not sure how to debug further. The app builds and runs fine on SDK 2.5.2.

Is this a bug in the SDK ? SDK v2.5.2 works well for me for now, but a fix or workaround would be much appreciated.

TIA

[Cambridge_dev]

Experimenting some more, the app runs fine if I change to using spi3 with SDK v2.6

[AHaug]

Hi,

Apologies for the long response time. We've had easter holidays in Norway for the past week. Thank you for reporting this. I will look into the lesson and check if there is anything that needs to be patched for 2.6.0 compatability. The lessons were created and tested for NCS v2.5.x only, so there might be changes needed for v2.6.0

Kind regards,
Andreas

[AHaug]

Hi,

I can confirm that the solution does not work out of the box for v2.6.0, but it does for the tested 2.5.1. We will look into making the sample in the course compatible out of the box with NCS 2.6.0 as well

Kind regards,
Andreas

[Cambridge_dev]

Hi Andreas,

Thanks for the update. 

Best regards,

Jeff

[Ali Aljaani]

Hi Cambridge_dev,

Thank you for reporting the issue. 

I managed to reproduce this issue on the nRF9160 DK (nrf9160dk_nrf9160_ns). It seems the problem occurs because logging is now enabled by default in TF-M with UART1 in nRF Connect SDK v2.6.0. UART1 on the nRF9160 has the same base address as SPIM. All you need to do is add these two lines in prj.conf to disable logging in TF-M .

CONFIG_TFM_SECURE_UART=n

CONFIG_TFM_LOG_LEVEL_SILENCE=y

Could you please try it out and confirm the fix ?

I will push the fix to the academy. 

Kind regards,

Ali