Partition Manager and NVS size change

[Bryan]

OS: Windows 10

NCS: 2.0.0

In a single image setup (no DFU) NVS (https://developer.nordicsemi.com/nRF_Connect_SDK/doc/2.0.0/zephyr/samples/subsys/nvs/README.html) uses the device tree storage_partition in the device tree file.

&flash0 {

    partitions {

        compatible = "fixed-partitions";

        #address-cells = <1>;

        #size-cells = <1>;

        boot_partition: partition@0 {

            label = "mcuboot";

            reg = <0x000000000 0xC000>;

        };

        slot0_partition: partition@c000 {

            label = "image-0";

            reg = <0x0000C000 0x32000>;

        };

        slot1_partition: partition@3e000 {

            label = "image-1";

            reg = <0x0003E000 0x32000>;

        };

        scratch_partition: partition@70000 {

            label = "image-scratch";

            reg = <0x00070000 0xA000>;

        };

        storage_partition: partition@7a000 {

            label = "storage";

            reg = <0x0007A000 0x00006000>;

        };

    };

};

That is working perfectly to store some gazell parameters.

#define STORAGE_NODE_LABEL storage  // device tree "storage" label

struct nvs_fs fs;

struct flash_pages_info info;

gazell_flash_data_t gzll_flash_data;

void flash_init(void){

    int rc = 0;

    printk("Initializing flash device...\n");

    /* define the nvs file system by settings with:

     *  sector_size equal to the pagesize,

     *  3 sectors

     *  starting at FLASH_AREA_OFFSET(storage)

     */

    fs.flash_device = FLASH_AREA_DEVICE(STORAGE_NODE_LABEL);

    if (!device_is_ready(fs.flash_device)) {

        printk("Flash device %s is not ready\n", fs.flash_device->name);

        return;

    }

    fs.offset = FLASH_AREA_OFFSET(storage);

    rc = flash_get_page_info_by_offs(fs.flash_device, fs.offset, &info);

    if (rc) {

        printk("Unable to get page info\n");

        return;

    }

    fs.sector_size = info.size;

    fs.sector_count = 3U;

    rc = nvs_mount(&fs);

    if (rc) {

        printk("Flash Init failed\n");

        return;

    }

   

}

Now we are moving to a BLE DFU multi-image setup.  The partition manager

(https://developer.nordicsemi.com/nRF_Connect_SDK/doc/2.2.0/nrf/scripts/partition_manager/partition_manager.html)

takes control of the flash partitioning and ignores the device tree mapping.  I have added the \child_image\mcuboot\boards\nrf52833dk_nrf52833.conf

to my project (see attached) for the child image.


west build -t partition_manager_report

+-----------------------------------------------------------------------+
| 0x0: mcuboot (0x6000 - 24kB)                                     |
+---0x6000: mcuboot_primary (0x3a000 - 232kB)-------+
| 0x6000: mcuboot_pad (0x200 - 512B)                         |
+---0x6200: mcuboot_primary_app (0x39e00 - 231kB)-+
| 0x6200: app (0x39e00 - 231kB)                                   |
+-----------------------------------------------------------------------+
| 0x40000: mcuboot_secondary (0x3a000 - 232kB)       |
| 0x7a000: nvs_storage (0x6000 - 24kB)                        |
+-----------------------------------------------------------------------+

We only need about 512 bytes of nvs_storage and I want to free up more space for the application.

How do I change the nvs_storage size?

nrf52833dk_nrf52833.zip

[Kenneth]

We only need about 512 bytes of nvs_storage and I want to free up more space for the application.

How do I change the nvs_storage size?

This should be controlled by the following kconfig option:

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/kconfig/index.html#CONFIG_PM_PARTITION_SIZE_NVS_STORAGE

However you need to set asiden minimum two flash pages (one for data and use for swap/scratch, so minimum will unfortunately be 8kB):

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/services/storage/nvs/nvs.html 

"NVS_SECTOR_COUNT is the number of sectors, it is at least 2, one sector is always kept empty to allow copying of existing data."