Some UART registers don't change after changing in .overlay

RE: Some UART registers don't change after changing in .overlay

Håkon Alseth — Mon, 10 Aug 2020 10:39:56 GMT

Hi,

I'm glad to hear that it worked!

The SPM is the secure part of the multi-image build process:

http://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.3.0/nrf/ug_multi_image.html

And the SPM module documentation is available here:

http://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.3.0/nrf/include/spm.html?highlight=spm

By adding the lines to your cmakelists.txt, you can now configure spm, overlay, and mcuboot specific to your wanted configuration (even when doing multi-image builds). Note that if you want this in other projects, you will need to append those lines to the cmakelists.txt project file there as well.

Kind regards,

Håkon

RE: Some UART registers don't change after changing in .overlay

Yury Morgunov — Mon, 10 Aug 2020 10:20:47 GMT

Oh no, sorry. Adding spm.conf file helped! I forgot to clear flash on nrf9160.
This is good, it would be great to learn more about how SPM works. I used to think that its functionality is limited to memory protection.

Is there any simple description of how it works, what and how it uses and how it can be customized?

RE: Some UART registers don't change after changing in .overlay

Yury Morgunov — Mon, 10 Aug 2020 10:14:57 GMT

Thanks for the answer!
Do I understand correctly that by describing the spm.conf file I am setting up the SPM functionality?
Those. it turns out that SPM configures its peripherals (for example uart 0) and therefore my configuration described in the device tree is not applied?

How can I then find out what is using and overriding SPM?
I have the same problem with uart1.

I just tried adding the spm.conf file next to prj.conf. CMakeLists hasn't changed yet.
Added to it:
CONFIG_SERIAL = n

But I did not see any changes, uart0 continues to work on pins 29 and 28.

RE: Some UART registers don't change after changing in .overlay

Håkon Alseth — Fri, 07 Aug 2020 10:21:20 GMT

Hi,

Its the SPM configuration that overrides your wanted configuration.

Could you try the sequence described here?

https://devzone.nordicsemi.com/f/nordic-q-a/60471/nrf9160-psm-current-consumption-test-problem/245872#245872

then re-generate your project, and it should also override the spm image.

You can also create a file "spm.conf" which disables serial (CONFIG_SERIAL=n)

Kind regards,

Håkon

RE: Some UART registers don't change after changing in .overlay

Yury Morgunov — Fri, 07 Aug 2020 09:39:10 GMT

As I found out, we cannot change these registers when uart is on.
It turns out that when the program starts. Before running main.
uart0 is already included and, accordingly, no initialization occurs.
Why is this happening?