FIXED_PARTITION_ID macro unable to identify flash partition from overlay

[gabagool]

I'll preface this by saying I am new to developing on the nRF and the Zephyr OS. 

I am just trying to set up a flash read/write module on my nRF52DK PCA100040 model. From my readings, it seems I need to first set up a flash partition which is done in an overlay file. In my VSCode config, I added the .overlay file as an "Extra Device Tree Overlay". 

The contents of my .overlay file is:

&flash0 {
    partitions {
        compatible = "fixed-partitions";
        #address-cells = <1>;
        #size-cells = <1>;
   
        rolling_buffer: partition@7F000 {
            label = "rolling_buffer";
            reg = <0x7F000 0x1000>; /* 32b for log storage */
            compatible = "fixed-partition";
        };
    };
};

And my initFlash() function is just:

void initFlash()
{    
    int rc;
    rc = flash_area_open(FIXED_PARTITION_ID(rolling_buffer), &fa);
    if (rc) {
        printk("Failed to open flash partition (%d)\n", rc);
        // return;
    }
}

And when I compile I get the error:

C:/ncs/v3.1.0/nrf/include/flash_map_pm.h:47:22: error: 'PM_rolling_buffer_ID' undeclared (first use in this function)
   47 | #define PM_ID(label) PM_##label##_ID

My prj.conf file:

CONFIG_GPIO=y
CONFIG_SENSOR=y
CONFIG_ADC=y
CONFIG_PRINTK=y
CONFIG_CBPRINTF_FP_SUPPORT=y
CONFIG_FLASH=y
CONFIG_FLASH_PAGE_LAYOUT=y
CONFIG_FLASH_MAP=y
CONFIG_FCB=y
CONFIG_LOG=y

build command:

west build --build-dir C:/logger/build C:/logger/build --pristine --board nrf52dk/nrf52832 --sysbuild -- -DCONF_FILE="prj.conf" -DEXTRA_DTC_OVERLAY_FILE=nrf52832dk_nrf52832.overlay -DCONFIG_DEBUG_OPTIMIZATIONS=y -DCONFIG_DEBUG_THREAD_INFO=y

What's  going on here? I feel like I have tried almost everything I can within my current understanding, but can't seem to get this to work. I am using SDK and Toolchain v3.1.0.

[gabagool]

I was looking at the zephyr/samples/subsys/nvs/src/main.c file. It seems replacing FIXED_PARTITION_ID with FIXED_PARTITION_DEVICE resolves this? I'm not really sure why though. 

[Håkon Alseth]

Hi,

 

You should use partition manager to define your partition:

https://docs.nordicsemi.com/bundle/ncs-3.0.1/page/nrf/scripts/partition_manager/partition_manager.html#adding_a_static_partition

The default is to use sysbuild for all versions newer than NCS v2.7.0:

The Partition Manager is activated for all sysbuild builds.

Meaning that it will be using partition manager even for single-image builds.

 

gabagool said:

It seems replacing FIXED_PARTITION_ID with FIXED_PARTITION_DEVICE resolves this? I'm not really sure why though. 

You should change this macro to match the partition name:

https://github.com/nrfconnect/sdk-zephyr/blob/main/samples/subsys/nvs/src/main.c#L51

 

Kind regards,

Håkon

[gabagool]

I'm confused on the use of the pm_static.yaml file and the .overlay file. If I want to just create a in flash of size 2k, how can I achieve this? How does the compiler know of the pm_static.yaml file, and do I need to add the partition to the .yaml file as well as the .overlay file?

If I have what I have in my  .overlay file, then do I need the following in my pm_static.yaml file?

rolling_buffer:
    address: 0x7F000
    size: 0x0800

[Håkon Alseth]

Hi,

 

You will need to align on a flash page, ie. 0x1000 bytes.

gabagool said:

How does the compiler know of the pm_static.yaml file, and do I need to add the partition to the .yaml file as well as the .overlay file?

if pm_static.yml exists, the build system will pick it up and use that for static partitioning, as described in the former link, ie. the documentation for the partition manager.

gabagool said:

If I have what I have in my  .overlay file, then do I need the following in my pm_static.yaml file?

partitions in overlay will not be picked up by the partition manager, they will need to be declared in the pm_static.yml file.

 

Kind regards,

Håkon