nrf52840 nrfx gpiote zephyr thread unresponsive

[lvh831]

Hi all,

I'm using the nrfx gpiote to setup an interrupt from an external device (IMU.) Whenever there is an interrupt, I would post an event and process it in another thread. The problem I'm facing is that this post event from the ISR doesn't get processed until I press any key in the shell. I'm uncertain how does the shell CLI is related to processing a thread.

This problem does not occurred in ISRs from other sources such as SPIM or TIMER instances. Any event post from either SPIM or TIMER ISRs would get processed immediately. So I am wondering if the problem could be coming from the gpiote ISR that blocks the event to be processed immediately.

Attached is a sample showing event post from three different ISRs (press a button, SPIM, and TIMER) for nrf52840 with a shell. 

Shell Commands:

i 0   # to  initialize

After this, you can press a BUTTON 1. Then press any key in the shell would see the post event gets processed

i 1  # run spim test

This shows the post event gets processed immediately (without typing anything into the shell)

i 2 # run timer test

This has the behavior like the spim test.

Thank you for so much for your help.

[Kenneth]

Hello,

I was not able to compile your project, likely I am using the wrong board and/or ncs version.

I think however your problem may be related to the use and description of IRQ_DIRECT_CONNECT:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/kernel/services/interrupts.html#c.IRQ_DIRECT_CONNECT  

I suggest you for instance try to use ISR_DIRECT_DECLARE(nrfx_gpiote_irq_handler) if you want to use IRQ_DIRECT_CONNECT.

Alternatively don't use IRQ_DIRECT_CONNECT, but use IRQ_CONNECT.

Kenneth

[lvh831]

Hi Kenneth,

The ncs version I'm using is 2.5 and the board is nrf52840dk_nrf52840. I tried to trace the code with ozone and noticed that as soon as I trigger the gpiote interrupt, it does switch to key1_thread which means the ISR is okay since it posts an event to this thread.

But I think it still stays there waiting for k_event_wait(..)

I attached a zip version of this code that you try to build the project again with ncs 2.5

[Kenneth]

That is likely right, I can see from the documentation:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/kernel/services/interrupts.html#concepts 

"Many kernel APIs can be used only by threads, and not by ISRs. In cases where a routine may be invoked by both threads and ISRs the kernel provides the k_is_in_isr() API to allow the routine to alter its behavior depending on whether it is executing as part of a thread or as part of an ISR."

I have not looked at your project to see if you are already doing this though.

Kenneth

[lvh831]

Hi Kenneth,

Thank you so much for sharing the info. I couldn't use IRQ_CONNECT because I bypassed Zephyr stuff (initialization and devicetree etc.) The problem I noticed was with the scheduler. In directly using your suggestion: ISR_DIRECT_DECLARE, ISR_DIRECT_FOOTER(1) got it to work. Thanks.