After enabling MCUBoot in NCS, external flash doesn't get picked up by littleFS

[akw]

Hello:

I am using an nrf52840 on a custom board with W25Q01NV NOR Flash with the Nordic QSPI-NOR driver. Programming is with NCS v 1.8.0 (upgraded yesterday) and the VS Code extension.  I am using the external Flash partition only for storage of data collected by the device and not for use with MCUBoot or for anything else. This setup was previously working with nrf5 SDK and recently moved to NCS.

When the CONFIG_BOOTLOADER_MCUBOOT option is not enabled, the code works fine, mounts the parittion and starts recording the data, but when I enable MCUBoot, LittleFS mounts on an internal flash parition. I found this related issue here: https://devzone.nordicsemi.com/f/nordic-q-a/62212/external-spi-flash-to-use-with-littlefs-on-nrf9160-w-mcuboot, but that was from a year ago and there was no resolution to that issue.

Again, I do not want to store MCUBoot images on the external flash, but I want to still use it for storage and I need MCUBoot enabled for upgrades as usual with the internal flash only. 

Any help is appreciated. 

Ashwin

[Simon]

Could you run the command below from the build folder and upload the result here?

ninja partition_manager_report

Best regards,

Simon 

[akw]

Thanks Simon. This is the output of the patition manager report. 

flash_primary (0x100000 - 1024kB):

+-------------------------------------------------+

| 0x0: mcuboot (0xc000 - 48kB) |

+---0xc000: mcuboot_primary (0x77000 - 476kB)-----+

| 0xc000: mcuboot_pad (0x200 - 512B) |

+---0xc200: mcuboot_primary_app (0x76e00 - 475kB)-+

| 0xc200: app (0x76e00 - 475kB) |

+-------------------------------------------------+

| 0x83000: mcuboot_secondary (0x77000 - 476kB) |

| 0xfa000: littlefs_storage (0x6000 - 24kB) |

+-------------------------------------------------+

sram_primary (0x40000 - 256kB):

+--------------------------------------------+

| 0x20000000: sram_primary (0x40000 - 256kB) |

+--------------------------------------------+

[Simon]

Try setting CONFIG_PM_EXTERNAL_FLASH_MCUBOOT_SECONDARY=n in the prj.conf of your application. Then the secondary slot will no longer be located in the external flash

If you have enabled external flash and mcuboot, the secondary slot will automatically be placed in the ext. flash. The config PM_EXTERNAL_FLASH_MCUBOOT_SECONDARY will get the value 'y'.

---

An important thing to be aware of is that the flash partitions from the DTS will be ignored if the sample have child images. The partitions from the Partition Manager will be used instead. For example when you enable MCUboot, your application will add MCUboot as a child image (see <application>/build/mcuboot) and the DTS flash partitions will get ignored.

The partitions from the Partition Mangager will be generated dynamically bases on pm.yml files, for example:

• ncs/bootloader/mcuboot/boot/zephyr/pm.yml
• ncs/nrf/subsys/partition_manager/pm.yml.file_system

or they can be set statically, like it's done in the matter/lock sample:

https://github.com/nrfconnect/sdk-nrf/blob/v1.8.0/samples/matter/lock/configuration/nrf52840dk_nrf52840/pm_static.yml

Read more about the Partition Manager in the documentation:

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.8.0/nrf/scripts/partition_manager/partition_manager.html

[akw]

Thank you Simon, for your detailed reply. Let me try all of these points and get back with the result. 

[akw]

I have now added these to the pm_static.yml

external_flash:

address: 0x120000

placement:

after:

- mcuboot_secondary

size: 0x6e0000

device: W25Q01JV

region: external_flash

littlefs_storage:

address: 0x00000

size: 0x7a000

device: W25Q01JV

region: external_flash

And now the littlefs_storage doesn't seem to be located in primary flash:

  flash_primary (0x100000 - 1024kB): 

+-------------------------------------------------+

| 0x0: mcuboot (0xc000 - 48kB)                    |

+---0xc000: mcuboot_primary (0x7a000 - 488kB)-----+

| 0xc000: mcuboot_pad (0x200 - 512B)              |

+---0xc200: mcuboot_primary_app (0x79e00 - 487kB)-+

| 0xc200: app (0x79e00 - 487kB)                   |

+-------------------------------------------------+

| 0x86000: mcuboot_secondary (0x7a000 - 488kB)    |

+-------------------------------------------------+

  sram_primary (0x40000 - 256kB): 

+--------------------------------------------+

| 0x20000000: sram_primary (0x40000 - 256kB) |

+--------------------------------------------+

But when the code starts, it still seems to pickup from the same NRV_FLASH_DRV_NAME paritition. 

*** Booting Zephyr OS build v2.7.0-ncs1 ***
I: Starting bootloader
I: Primary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Secondary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Boot source: none
I: Swap type: none
I: Bootloader chainload address offset: 0xc000
I: Jumping to the first image slot [00:00:00.143,432] [0m<inf> littlefs: littlefs partition at /lfs1[0m
*** Booting Zephyr OS build v2.7.0-ncs1 ***
[00:00:00.143,676] [0m<inf> sdc_hci_driver: SoftDevice Controller build revision:
df c0 4e d6 1f 7c 66 09 0a f5 2b a0 98 f2 43 64 |..N..|f. ..+...Cd
62 c5 a6 2a |b..* [0m
Bluetooth initialized
Advertising successfully started
Found device MAX17262
Found device LSM6DSL
Found device TPS65721
Found device MAX30003
Starting in PatchPro ModeSend Data Thrd STRT

Mounting Disk...

Area 0 at 0x0 on NRF_FLASH_DRV_NAME for 49152 bytes
[00:00:00.649,719] [0m<inf> littlefs: LittleFS version 2.2, disk version 2.0[0m
[00:00:00.649,780] [0m<inf> littlefs: FS at NRF_FLASH_DRV_NAME:0x0 is 12 0x1000-byte blocks with 512 cycle[0m
[00:00:00.649,780] [0m<inf> littlefs: sizes: rd 32 ; pr 32 ; ca 64 ; la 32[0m
[00:00:00.649,871] [1;31m<err> littlefs: WEST_TOPDIR/modules/fs/littlefs/lfs.c:997: Corrupted dir pair at {0x0, 0x1}[0m
[00:00:00.649,871] [1;33m<wrn> littlefs: can't mount (LFS -84); formatting[0m
[00:00:00.680,755] [1;31m<err> os: ***** BUS FAULT *****[0m

It looks to me like that this is picked up from some other place.

[Simon]

I don't have W25Q01NV NOR Flash. But I was able to get this to work using the nRF52840 DK an it's integrated external flash.

In the sample below, the littlefs storage is placed inside the external flash, and the secondary slot is placed in the primary slot

2654.littlefs_ext_flash_sec_slot_in_internal.zip

If it works successfully, you should get the following output:

*** Booting Zephyr OS build v2.7.0-ncs1  ***
I: Starting bootloader
I: Primary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Secondary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Boot source: none
I: Swap type: none
I: Bootloader chainload address offset: 0xc000
*** Booting Zephyr OS build v2.7.0-ncs1  ***
Area 1 at 0x0 on MX25R64 for 24576 bytes
/lfs mount: 0
[/lfs: bsize = 16 ; frsize = 4096 ; blocks = 6 ; bfree = 4
00/lfs/boot_count stat: 0
        fn 'boot_count' size 4
:00/lfs/boot_count read count 2: 4
/lfs/boot_count seek start: 0
/lfs/boot_count write new boot count 3: 4
:00/lfs/boot_count close: 0
.00/lfs opendir: 0
  F 4 boot_count
End of files
/lfs unmount: 0
7,843] <inf> littlefs: LittleFS version 2.2, disk version 2.0
[00:00:00.007,873] <inf> littlefs: FS at MX25R64:0x0 is 6 0x1000-byte blocks with 512 cycle
[00:00:00.007,873] <inf> littlefs: sizes: rd 16 ; pr 16 ; ca 64 ; la 32
[00:00:00.009,826] <inf> littlefs: /lfs mounted
[00:00:00.043,334] <inf> littlefs: /lfs unmounted

This is the result after running ninja partition_manager_report:

  external_flash (0x800000 - 8192kB): 
+-----------------------------------------+
| 0x0: external_flash (0x800000 - 8192kB) |
| 0x0: littlefs_storage (0x6000 - 24kB)   |
+-----------------------------------------+

  flash_primary (0x100000 - 1024kB): 
+-------------------------------------------------+
| 0x0: mcuboot (0xc000 - 48kB)                    |
+---0xc000: mcuboot_primary (0x7a000 - 488kB)-----+
| 0xc000: mcuboot_pad (0x200 - 512B)              |
+---0xc200: mcuboot_primary_app (0x79e00 - 487kB)-+
| 0xc200: app (0x79e00 - 487kB)                   |
+-------------------------------------------------+
| 0x86000: mcuboot_secondary (0x7a000 - 488kB)    |
+-------------------------------------------------+

  sram_primary (0x40000 - 256kB): 
+--------------------------------------------+
| 0x20000000: sram_primary (0x40000 - 256kB) |
+--------------------------------------------+

Could you test this first with the nRF52840 DK, and if that runs successfully, modify it it to work with the W25Q01JV.

Best regards,

Simon 

[akw]

Thank you Simon for posting the sample project. 

I can confirm that this indeed works with the nrf DK board. 

Also, on my board, the partition structure is showing fine. 

  external_flash (0x8000000 - 131072kB): 
+----------------------------------------------+
| 0x0: external_flash (0x8000000 - 131072kB)   |
| 0x0: littlefs_storage (0x8000000 - 131072kB) |
+----------------------------------------------+

  flash_primary (0x100000 - 1024kB): 
+-------------------------------------------------+
| 0x0: mcuboot (0xc000 - 48kB)                    |
+---0xc000: mcuboot_primary (0x7a000 - 488kB)-----+
| 0xc000: mcuboot_pad (0x200 - 512B)              |
+---0xc200: mcuboot_primary_app (0x79e00 - 487kB)-+
| 0xc200: app (0x79e00 - 487kB)                   |
+-------------------------------------------------+
| 0x86000: mcuboot_secondary (0x7a000 - 488kB)    |
+-------------------------------------------------+

  sram_primary (0x40000 - 256kB): 
+--------------------------------------------+
| 0x20000000: sram_primary (0x40000 - 256kB) |
+--------------------------------------------+

The following were the essential things I changed (compared to my previous configuration to make this work):

1. Define partitions only in the pm_static.yml file (earlier I was declaring everything, including littlefs config in an overlay file using an fstab entry). In my code now, I define the FS entry inline itself.

2. Added this to my overlay : 

/ {

chosen {

nordic,pm-ext-flash = &w25q01jv;

};

};

3. Include the option CONFIG_PM_EXTERNAL_FLASH_MCUBOOT_SECONDARY=n in my prj.conf file

I am getting a different error now saying that it cannot find the flash device, but I guess that must be a different issue. I will check and raise another ticket if necessary, but here is my output after this:

*** Booting Zephyr OS build v2.7.0-ncs1  ***
I: Starting bootloader
I: Primary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Secondary image: magic=unset, swap_type=0x1, copy_done=0x3, image_ok=0x3
I: Boot source: none
I: Swap type: none
I: Bootloader chainload address offset: 0xc000
I: Jumping to the first image slot
*** Booting Zephyr OS build v2.7.0-ncs1  ***

[00:00:00.143,768] <inf> sdc_hci_driver: SoftDevice Controller build revision: 
                                         df c0 4e d6 1f 7c 66 09  0a f5 2b a0 98 f2 43 64 |..N..|f. ..+...Cd
                                         62 c5 a6 2a                                      |b..*             
Bluetooth initialized

Advertising successfully started

Found device MAX17262

Found device LSM6DSL

Found device TPS65721

Found device MAX30003

Starting in PatchPro ModeSend Data Thrd STRT

Mounting Disk...

Area 1 at 0x0 on W25Q01JV for 134217728 bytes

[00:00:00.950,225] <inf> littlefs: LittleFS version 2.2, disk version 2.0
[00:00:00.950,256] <err> littlefs: can't get flash device: W25Q01JV
[00:00:00.950,256] <err> fs: fs mount error (-19)
FAIL: mount id 1 at /lfs1: -19

Load IDX...

[00:00:01.950,500] <err> fs: mount point not found!!
FAIL: open /lfs1/index: -2