How to place the custom linker section in the .data section?

RE: How to place the custom linker section in the .data section?

Hieu — Mon, 17 Mar 2025 16:09:56 GMT

My apology. I misread the other ticket.

There are a couple of way to do this.

The first one is to use Zephyr linker tool APIs, described here: https://docs.nordicsemi.com/bundle/zephyr-apis-2.9.1/page/linker-tool-gcc_8h.html
A custom linker file needs to be used with it, and you can provide the linker file with the command zephyr_linker_sources() in your CMakeLists.txt.

Here are a few examples uses you can refer to:
sdk-zephyr/tests/application_development/code_relocation at v3.7.99-ncs2 · nrfconnect/sdk-zephyr
debug: tracing: Add Segger RTT linker section options · zephyrproject-rtos/zephyr@711ed08

Another method is discussed in this DevZone case:
Define a section to consistently place rtt

RE: How to place the custom linker section in the .data section?

AlphaBeta — Fri, 14 Mar 2025 13:19:35 GMT

Both questions have different context.

In this question, I am able to create my own data section in RAM. However, the global variables I place in this section do not have the correct initial values that I expect. This is because they should be placed under ".data" section for the compiler to recognize about correct initialization.

In the final linker.cmd, I am expecting it to appear like the following (I just manually added this line for explanation purpose).

I do not know how to automatically do this since linker.cmd is automatically generated.

RE: How to place the custom linker section in the .data section?

Hieu — Fri, 14 Mar 2025 13:12:14 GMT

Hi AlphaBeta,

I see you created this case How can I add postbuild options to compute a checksum and add it at an address in Flash? .

From that case's text, it seems you already figured out how to create your own custom section in Flash.

If you already have the answer, it would be great if you could share it here for future readers.

Hieu