MCU boot with external Flash littles partition and Secondary image partition

Question

Hello ALL,

I am trying to use MCU boot with my application. I am using NRF916DK and it has external Flash similar to NR52840DK board. Now when I am creating a partition on external Flash and point LittleFs to that storage partition, after compiling when I see the partition.yml in the build folder, the LittleFs always in the primary Flash. I have tried few options as seen in the code but nothing is working. Can somebody please guide me on how I can enable these partitions and point secondary Image and littlefs to those partitions.

Here is my overlay file


/ {
	chosen {
		zephyr,bt-uart=&uart0;
	};
};

/delete-node/ &storage_partition;

&i2c2 {
    compatible = "nordic,nrf-twim";
    status = "okay";
    sda-pin = <26>;
    scl-pin = <27>;

    pcf85263a@51 {
        compatible = "nxp,pcf85263a";
        label = "PCF85063A";
        reg = <0x51>;
    };

};

&uart1 {
	status = "okay";
	current-speed = <9600>;
	tx-pin = <06>;
	rx-pin = <07>;
};


&spi3 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	sck-pin = <13>;
	mosi-pin = <11>;
	miso-pin = <12>;
	cs-gpios = <&gpio0 25 GPIO_ACTIVE_LOW>;
	mx25r6435f: mx25r6435f@0 {
		compatible = "jedec,spi-nor";
		label = "MX25R6435F";
		reg = <0>;
		spi-max-frequency = <40000000>;
		wp-gpios = <&gpio0 8 GPIO_ACTIVE_LOW>;
		hold-gpios = <&gpio0 10 GPIO_ACTIVE_LOW>;
		jedec-id = [c2 28 14];
  		size = <0x0800000>; /* flash capacity in bits */
  		has-be32k;
  		has-dpd;
  		t-enter-dpd = <10000>;
  		t-exit-dpd = <35000>;
	};
};


&mx25r6435f {
 	partitions {
  		compatible = "fixed-partitions";
  		#address-cells = <1>;
  		#size-cells = <1>;
		storage_partition: partition@40000 {
   			label = "storage";
   			reg = <0x00040000 0x00020000>;
  		};
 	};
};

Here is prj.conf

# Heap and stacks
CONFIG_HEAP_MEM_POOL_SIZE=16384
CONFIG_MAIN_STACK_SIZE=8192
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2048

# General config
CONFIG_NEWLIB_LIBC=y
CONFIG_NEWLIB_LIBC_FLOAT_PRINTF=y
CONFIG_ASSERT=y
CONFIG_REBOOT=y

# Logging config
CONFIG_LOG=y
CONFIG_LOG_PRINTK=y
CONFIG_LOG_IMMEDIATE=y
CONFIG_LOG_FUNC_NAME_PREFIX_ERR=y
CONFIG_LOG_FUNC_NAME_PREFIX_WRN=y
CONFIG_LOG_FUNC_NAME_PREFIX_INF=y
CONFIG_LOG_FUNC_NAME_PREFIX_DBG=y

# Console
CONFIG_STDOUT_CONSOLE=y
CONFIG_PRINTK=y
CONFIG_CONSOLE_SUBSYS=y
CONFIG_CONSOLE_HANDLER=y
CONFIG_CONSOLE_GETCHAR=y

# PWM
CONFIG_PWM=y
CONFIG_PWM_LOG_LEVEL_DBG=y

# I2C
CONFIG_I2C=y

# RTC
CONFIG_PCF85263A=y

# UART
CONFIG_UART_ASYNC_API=y
CONFIG_UART_1_ASYNC=y
CONFIG_UART_1_INTERRUPT_DRIVEN=n
CONFIG_UART_1_NRF_HW_ASYNC=n
CONFIG_UART_1_NRF_HW_ASYNC_TIMER=2
CONFIG_NRFX_TIMER2=y
CONFIG_NRFX_UARTE1=y

CONFIG_NRFX_SPIM=y
CONFIG_NRFX_SPIM3=y

# CONFIG_NRFX_SPI=y
# CONFIG_NRFX_SPI0=y
CONFIG_BSD_LIBRARY_TRACE_ENABLED=n

# SPI Flash
CONFIG_SPI=y
CONFIG_SPI_NOR=y
CONFIG_SPI_NOR_FLASH_LAYOUT_PAGE_SIZE=4096

# Enable flash operations.
CONFIG_FLASH=y
CONFIG_FLASH_MAP=y
CONFIG_FLASH_PAGE_LAYOUT=y



# Nordic specific external flash stuff
CONFIG_PM_EXTERNAL_FLASH=y
CONFIG_PM_EXTERNAL_FLASH_DEV_NAME="MX25R6435F"
CONFIG_PM_EXTERNAL_FLASH_BASE=0x0
CONFIG_PM_EXTERNAL_FLASH_SIZE=0x0800000

# Enable the LittleFS file system.
CONFIG_FILE_SYSTEM=y
CONFIG_FILE_SYSTEM_LITTLEFS=y
# CONFIG_APP_WIPE_STORAGE=n

# MCUBOOT
CONFIG_BOOTLOADER_MCUBOOT=y
CONFIG_IMG_MANAGER=y
CONFIG_MCUBOOT_IMG_MANAGER=y

Here is my main.c

#include <zephyr.h>
#include <logging/log.h>
#include <drivers/uart.h>

#include <fs/fs.h>
#include <fs/littlefs.h>
#include <storage/flash_map.h>

#if (CONFIG_SPI_NOR - 0) || DT_NODE_HAS_STATUS(DT_INST(0, jedec_spi_nor), okay)
#define FLASH_DEVICE DT_LABEL(DT_INST(0, jedec_spi_nor))
#define FLASH_NAME "JEDEC SPI-NOR"
#elif (CONFIG_NORDIC_QSPI_NOR - 0) || DT_NODE_HAS_STATUS(DT_INST(0, nordic_qspi_nor), okay)
#define FLASH_DEVICE DT_LABEL(DT_INST(0, nordic_qspi_nor))
#define FLASH_NAME "JEDEC QSPI-NOR"
#else
#error Unsupported flash driver
#endif

LOG_MODULE_REGISTER(app);

/* Matches LFS_NAME_MAX */
#define MAX_PATH_LEN 255

FS_LITTLEFS_DECLARE_DEFAULT_CONFIG(lfsstorage);
static struct fs_mount_t lfs_storage_mnt = {
		.type = FS_LITTLEFS,
		.fs_data = &lfsstorage,
		//.storage_dev = (void *)DT_FLASH_AREA_STORAGE_ID,
		.storage_dev = (void *)FLASH_AREA_ID(storage),
		//.storage_dev = (void *)FLASH_AREA_ID(external_flash),
		.mnt_point = "/lfs",
};

here is the partition.yml that is generated in the build folder after compilation

EMPTY_0:
  address: 0xc000
  placement:
    before:
    - mcuboot_pad
  region: flash_primary
  size: 0x4000
app:
  address: 0x1c200
  region: flash_primary
  size: 0x68e00
external_flash:
  address: 0x0
  region: external_flash
  size: 0x800000
littlefs_storage:
  address: 0xfa000
  placement:
    before:
    - end
  region: flash_primary
  size: 0x6000
mcuboot:
  address: 0x0
  placement:
    before:
    - mcuboot_primary
  region: flash_primary
  size: 0xc000
mcuboot_pad:
  address: 0x10000
  placement:
    align:
      start: 0x8000
    before:
    - mcuboot_primary_app
  region: flash_primary
  size: 0x200
mcuboot_primary:
  address: 0x10000
  orig_span: &id001
  - spm
  - mcuboot_pad
  - app
  region: flash_primary
  sharers: 0x1
  size: 0x75000
  span: *id001
mcuboot_primary_app:
  address: 0x10200
  orig_span: &id002
  - app
  - spm
  region: flash_primary
  size: 0x74e00
  span: *id002
mcuboot_secondary:
  address: 0x85000
  placement:
    after:
    - mcuboot_primary
    align:
      start: 0x1000
  region: flash_primary
  share_size:
  - mcuboot_primary
  size: 0x75000
otp:
  address: 0xff8108
  region: otp
  size: 0x2f4
spm:
  address: 0x10200
  inside:
  - mcuboot_primary_app
  placement:
    before:
    - app
  region: flash_primary
  size: 0xc000
spm_sram:
  address: 0x20000000
  inside:
  - sram_secure
  placement:
    after:
    - start
  region: sram_primary
  size: 0x10000
sram_primary:
  address: 0x20010000
  region: sram_primary
  size: 0x30000
sram_secure:
  address: 0x20000000
  orig_span: &id003
  - spm_sram
  region: sram_primary
  size: 0x10000
  span: *id003