Access External Flash as Raw/low-level device. No file system wanted

RE: Access External Flash as Raw/low-level device. No file system wanted

dejans — Tue, 08 Feb 2022 15:23:00 GMT

Hi Kevin,

I would not recommend you to start with blinky example. It would be better if you start from the clean littlefs example and then start adding what you need on top of that.

Best regards,
Dejan

RE: Access External Flash as Raw/low-level device. No file system wanted

KCrawford — Mon, 07 Feb 2022 16:56:26 GMT

Yes, I started with a fresh version of blinky for the nRF9160DK (ns).

I have a Windows 10 environment running on a brand new HP, Intel-based laptop

I haven't tried v1.8.0. yet. My deadlines don't really provide much time for experimentation unfortunately.

BTW, I am using SES for my IDE in case it matters.

RE: Access External Flash as Raw/low-level device. No file system wanted

dejans — Mon, 07 Feb 2022 16:40:35 GMT

Hi Kevin,

Did you use a completely new project for littlefs (unrelated to hello_world)?
Which operating system are you using and how did you run cmake?
Could you try using nRF Connect for Desktop v1.8.0? Is there any difference from v1.7.1 that you used?

Best regards,
Dejan

RE: Access External Flash as Raw/low-level device. No file system wanted

KCrawford — Fri, 04 Feb 2022 15:43:24 GMT

Hello Dejans, following your advice, I just created a Hello_World example using SES. I compiled and ran it successfully. Afterwards I ran Clean Solution.Then I just dropped the files from the littlefs.zip archive from Nordic into the project folder. Ran CMake and did a solution build. But I got the same crash. I'm attaching a zip with the project and logs into this ticket. In the root folder you will find the CMake log, the build log, and a screenshot of the crash info. Thanks in advance for your continued help!

devzone.nordicsemi.com/.../solution_5F00_and_5F00_logs.zip

RE: Access External Flash as Raw/low-level device. No file system wanted

dejans — Fri, 04 Feb 2022 14:10:25 GMT

Hi Kevin,

This would not be the proper place for partitioning information. They should reside in partition.yml (pm.yml), or in your case pm_static.yml.
<your_board>.yml file contains metadata used for testing as explained in board porting.

Best regards,
Dejan

RE: Access External Flash as Raw/low-level device. No file system wanted

dejans — Fri, 04 Feb 2022 13:32:44 GMT

Hi Kevin,

It is not necessary to put all partitioning information in pm_static.yml. Most of the work can be handled automatically by NCS itself.

Could you try to build a sample and let me know if there are any warnings/errors in the build output by sharing the build log?

Best regards,
Dejan

RE: Access External Flash as Raw/low-level device. No file system wanted

KCrawford — Thu, 03 Feb 2022 15:42:20 GMT

BTW Dejan, I was wondering if the nrf9160DK_nrf9160_ns.yaml file is where the external flash changes should be placed, versus the pm_static.yml file? Here are the entries in the nrf9160DK_nrf9160_ns.yaml file:

identifier: nrf9160dk_nrf9160_ns
name: nRF9160-DK-NRF9160-Non-Secure
type: mcu
arch: arm
toolchain:
- gnuarmemb
- xtools
- zephyr
ram: 128
flash: 192
supported:
- arduino_gpio
- arduino_i2c
- i2c
- pwm
- watchdog

RE: Access External Flash as Raw/low-level device. No file system wanted

KCrawford — Thu, 03 Feb 2022 13:52:04 GMT

Too keep things Dejans, I've decided to just use the littlefs on the 64MB external flash. The reason being is I want to have access to both the storage area storage area on the 1MB SiP flash for config info. And I want to store app data on the 64MB external flash device. And I won't need to access the littlefs at boot time.

But if I add the pm_static.yml that came with the littlefs.zip, then my application crashes with the following messages at boot:

Programming 75.4 KB of addresses 00020200 — 00032f9b
J-Link: Flash download: Bank 2 @ 0x00000000: 1 range affected (143360 bytes)
J-Link: Flash download: Total: 4.545s (Prepare: 0.146s, Compare: 0.032s, Erase: 3.062s, Program & Verify: 1.225s, Restore: 0.077s)
J-Link: Flash download: Program & Verify speed: 114 KiB/s
Download successful
Stopped by vector catch
Stopped by vector catch
Stopped by vector catch
Stopped by vector catch

If I remove the pm_static.yml file, my app builds and runs OK. But the littlefs sample code accesses the storage area of the 1MB flash, not the 64MB external flash.

So I assume the reason for the "stopped by vector catch" message is because pm_static.yml doesn't have the correct config for my build_nrf9160dk_nrf9160_ns application. I tried to attach the pm_static.yml file, but it doesn't seem to be working. Maybe it's my browser? (I'm using MS Edge if that matters). So instead, I'm pasting the YAML below. And by the way, I always re-run CMake when adding or removing the YAML file. Thanks in advance for your help.

app:

address: 0x20200

end_address: 0xfa000

region: flash_primary

size: 0xd9e00

external_flash:

address: 0x100000

end_address: 0x100000

region: external_flash

size: 0x00000

littlefs_storage:

address: 0xea000

device: MX25R64

end_address: 0x100000

region: external_flash

size: 0x16000

mcuboot:

address: 0x0

end_address: 0x10000

placement:

before:

- mcuboot_primary

region: flash_primary

size: 0x10000

mcuboot_pad:

address: 0x10000

end_address: 0x10200

placement:

align:

start: 0x8000

before:

- mcuboot_primary_app

region: flash_primary

size: 0x200

mcuboot_primary:

address: 0x10000

end_address: 0xfa000

orig_span: &id001

- mcuboot_pad

- spm

- app

region: flash_primary

size: 0xea000

span: *id001

mcuboot_primary_app:

address: 0x10200

end_address: 0xfa000

orig_span: &id002

- app

- spm

region: flash_primary

size: 0xe9e00

span: *id002

mcuboot_secondary:

address: 0x0

device: MX25R64

end_address: 0xea000

placement:

align:

start: 0x4

region: external_flash

size: 0xea000

nrf_modem_lib_ctrl:

address: 0x20010000

end_address: 0x200104e8

inside:

- sram_nonsecure

placement:

after:

- spm_sram

- start

region: sram_primary

size: 0x4e8

nrf_modem_lib_rx:

address: 0x200124e8

end_address: 0x200144e8

inside:

- sram_nonsecure

placement:

after:

- nrf_modem_lib_tx

region: sram_primary

size: 0x2000

nrf_modem_lib_sram:

address: 0x20010000

end_address: 0x200144e8

orig_span: &id003

- nrf_modem_lib_ctrl

- nrf_modem_lib_tx

- nrf_modem_lib_rx

region: sram_primary

size: 0x44e8

span: *id003

nrf_modem_lib_tx:

address: 0x200104e8

end_address: 0x200124e8

inside:

- sram_nonsecure

placement:

after:

- nrf_modem_lib_ctrl

region: sram_primary

size: 0x2000

otp:

address: 0xff8108

end_address: 0xff83fc

region: otp

size: 0x2f4

spm:

address: 0x10200

end_address: 0x20200

inside:

- mcuboot_primary_app

placement:

before:

- app

region: flash_primary

size: 0x10000

spm_sram:

address: 0x20000000

end_address: 0x20010000

inside:

- sram_secure

placement:

after:

- start

region: sram_primary

size: 0x10000

sram_nonsecure:

address: 0x20010000

end_address: 0x20040000

orig_span: &id004

- sram_primary

- nrf_modem_lib_ctrl

- nrf_modem_lib_tx

- nrf_modem_lib_rx

region: sram_primary

size: 0x30000

span: *id004

sram_primary:

address: 0x200144e8

end_address: 0x20040000

region: sram_primary

size: 0x2bb18

sram_secure:

address: 0x20000000

end_address: 0x20010000

orig_span: &id005

- spm_sram

region: sram_primary

size: 0x10000

span: *id005

RE: Access External Flash as Raw/low-level device. No file system wanted

dejans — Wed, 02 Feb 2022 14:52:32 GMT

Hi Kevin,

You would need to change the name of "littlefs_storage" section to a generic "storage" section in pm_static.yaml . Afterwards, you could access the storage using flash_area_open().

Best regards,
Dejan