Wrong read from settings_storage flash in nRF52840 and nRF Connect SDK 2.4.1

[Tomasz Chudy]

Hi,

I have an example based on v2.4.1\nrf\samples\bluetooth\peripheral_lbs

This is my prj.conf

# Flash
CONFIG_FLASH=y
CONFIG_FLASH_MAP=y
CONFIG_FLASH_PAGE_LAYOUT=y
CONFIG_MPU_ALLOW_FLASH_WRITE=y

# Bluetooth
CONFIG_BT=y
CONFIG_BT_PERIPHERAL=y
CONFIG_BT_DEVICE_NAME="Intonavi"

# FOTA
CONFIG_BOOTLOADER_MCUBOOT=y
CONFIG_NCS_SAMPLE_MCUMGR_BT_OTA_DFU=y
CONFIG_SECURE_BOOT=y
CONFIG_SB_SIGNING_KEY_FILE="d:/NordicSemiconductor/apps/ble_ota2/priv-ecdsa.pem"

this is my pm_static.yml, this is copy from file: build/partitions.yml

EMPTY_0:
  address: 0x15200
  end_address: 0x16000
  placement:
    before:
    - s1_pad
  region: flash_primary
  size: 0xe00
EMPTY_1:
  address: 0x22200
  end_address: 0x23000
  placement:
    before:
    - mcuboot_pad
  region: flash_primary
  size: 0xe00
EMPTY_2:
  address: 0xf5000
  end_address: 0xf6000
  placement:
    after:
    - mcuboot_secondary
  region: flash_primary
  size: 0x1000
app:
  address: 0x23200
  end_address: 0x8c000
  region: flash_primary
  size: 0x68e00
app_image:
  address: 0x23200
  end_address: 0x8c000
  orig_span: &id001
  - app
  region: flash_primary
  size: 0x68e00
  span: *id001
b0:
  address: 0x0
  end_address: 0x8000
  placement:
    after:
    - start
  region: flash_primary
  size: 0x8000
b0_container:
  address: 0x0
  end_address: 0x9000
  orig_span: &id002
  - b0
  - provision
  region: flash_primary
  size: 0x9000
  span: *id002
mcuboot:
  address: 0x9200
  end_address: 0x15200
  placement:
    before:
    - mcuboot_primary
  region: flash_primary
  sharers: 0x1
  size: 0xc000
mcuboot_pad:
  address: 0x23000
  end_address: 0x23200
  placement:
    align:
      start: 0x1000
    before:
    - mcuboot_primary_app
  region: flash_primary
  sharers: 0x2
  size: 0x200
mcuboot_primary:
  address: 0x23000
  end_address: 0x8c000
  orig_span: &id003
  - mcuboot_pad
  - app
  region: flash_primary
  sharers: 0x1
  size: 0x69000
  span: *id003
mcuboot_primary_app:
  address: 0x23200
  end_address: 0x8c000
  orig_span: &id004
  - app
  region: flash_primary
  size: 0x68e00
  span: *id004
mcuboot_secondary:
  address: 0x8c000
  end_address: 0xf5000
  placement:
    after:
    - mcuboot_primary
    align:
      start: 0x1000
  region: flash_primary
  share_size:
  - mcuboot_primary
  size: 0x69000
provision:
  address: 0x8000
  end_address: 0x9000
  placement:
    after:
    - b0
    align:
      start: 0x1000
  region: flash_primary
  size: 0x1000
s0:
  address: 0x9000
  end_address: 0x15200
  orig_span: &id005
  - s0_pad
  - mcuboot
  region: flash_primary
  size: 0xc200
  span: *id005
s0_image:
  address: 0x9200
  end_address: 0x15200
  orig_span: &id006
  - mcuboot
  region: flash_primary
  size: 0xc000
  span: *id006
s0_pad:
  address: 0x9000
  end_address: 0x9200
  placement:
    after:
    - b0_container
    align:
      start: 0x1000
  region: flash_primary
  share_size:
  - mcuboot_pad
  size: 0x200
s1:
  address: 0x16000
  end_address: 0x22200
  orig_span: &id007
  - s1_pad
  - s1_image
  region: flash_primary
  size: 0xc200
  span: *id007
s1_image:
  address: 0x16200
  end_address: 0x22200
  placement:
    after:
    - s1_pad
    - s0
  region: flash_primary
  share_size:
  - mcuboot
  size: 0xc000
s1_pad:
  address: 0x16000
  end_address: 0x16200
  placement:
    after:
    - s0
    align:
      start: 0x1000
  region: flash_primary
  share_size:
  - mcuboot_pad
  size: 0x200
settings_storage:
  address: 0xf6000
  end_address: 0xf8000
  placement:
    align:
      start: 0x1000
  region: flash_primary
  size: 0x2000
sram_primary:
  address: 0x20000000
  end_address: 0x20040000
  region: sram_primary
  size: 0x40000
storage_partition:
  address: 0xf8000
  end_address: 0x100000
  region: flash_primary
  size: 0x8000

I init parametres for settings_storage of flash

#define DATA_PARTITION_OFFSET FIXED_PARTITION_OFFSET (settings_storage)
#define DATA_PARTITION_DEVICE FIXED_PARTITION_DEVICE (settings_storage)

Now i do the following:

Build, Flash, with flash_erease, flash_write and flash_read. This is my console log

Flash is ready
Test 1: Flash erase page at 0xf6000
Flash erase succeeded!
Attempted to write 12c at 0xf6000
Data read: 12c | 300, at 0xf6000
Attempted to write 64 at 0xf6004
Data read: 64 | 100, at 0xf6004
Attempted to write 1 at 0xf6008
Data read: 1 | 1, at 0xf6008
Attempted to write 2 at 0xf600c
Data read: 2 | 2, at 0xf600c

Next step. Comment flash_erease and flash_write, only flash_read is active. Build and Flash device. This is my console log

Flash is ready
Data read: b8397b06 | -1204192506, at 0xf6000
Data read: 689acd9a | 1754975642, at 0xf6004
Data read: 615433a5 | 1632908197, at 0xf6008
Data read: 4293d3ff | 1116984319, at 0xf600c

Why values are different?

When I use storage_partition and hard address 0xf8000 everyfing is ok, after write all next reads have corrected values.

[Hieu]

Hi Tomasz,

The way the partition manager is setup, depends on Kconfig, it will give the such auto-generated partitions, like the settings_partition, the storage_partition and storage "aliases" in flash_map_pm.h. This is because certain modules and subsystems in the Zephyr RTOS are built requiring partitions with such name.

One such subsystem is Settings. It is used to store all of the persistent data that many subsystems and modules need.
The Settings subsystem by default uses the partition named storage. In your case, due to the aliasing, it would use the settings_storage partition.

That is most likely why your data is overwritten.

If you want to share the settings_storage partition with the Settings subsystem, you need to store your data outside of the region the Settings subsystem use. Here is a DevZone case where I explained about that: Zephyr NVS on an nRF5340_DK .

Regarding your partition named storage_partition, did you create it yourself for some purpose? I tried to build a Peripheral LBS with your prj.conf file. The partition.yml file generated does not have such a partition.
I recommend you avoid this name, as it collides with the name of the commonly used partition I mentioned above.

Hieu

[Tomasz Chudy]

Hi Hieu,

Thanks for your answer. Now I undesrtand why i cant write and read in settings_storage partition.

And thanks for info about storage_partition, i made clean build with new create app base on Paripheral LBS and i olso don't have this partition. I made many different things and I don't know when it was created. But i will make for myself partion where i will store my few settings avoiding to name settings_storage or storage_partition.

Once again thanks for your answer.

[Hieu]

Hi Tomasz,

It's great to know that your question has been resolved. Please feel free to close this thread at your convenience then.