NRF5340 Mass storage using partition manager points to wrong device.

Question

Hi, Im working with a 5340 dk, where i want to add a fatfs msc on the external flash togther with ble. From what i gather from ble examples uses pm and nvs to function.

So in this example https://docs.zephyrproject.org/latest/samples/subsys/usb/mass/README.html

The device tree storage partition is replaced in the overlay, however with the ble example this wont work since its using the PM.

So firstly i tried to modify the example to use PM instead, the overlay would be changed to use nordic,pm-ext-flash but then the application seem to fetch the wrong partition

Area 2 at 0x10000 on flash-controller@39000 for 262144 bytes and creates the filesystem on the internal flash?

Below are code snippets with changes to go from device tree to pm.

I have two questions.

1. How do i fix so that the external flash is targeted?

2. If i want to use ble and msc, how do i keep nvs params in internal flash(not deleting storage_partition?) and put the filesystem on the external flash?

3. The reference storage_partition seems to be static in zephyr, is it possible to add another or should one add the external flash as an id under this partition to be able to reference it in code as its done in the mass example?

Thanks!

/*
 * Copyright (c) 2020 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: Apache-2.0
 */

/delete-node/ &storage_partition;

&mx25r64 {
	partitions {
		compatible = "fixed-partitions";
		#address-cells = <1>;
		#size-cells = <1>;

		storage_partition: partition@0 {
			label = "storage";
			reg = <0x00000000 0x00020000>;
		};
	};
};

/{
	chosen
	{
		nordic,pm-ext-flash = &mx25r64;

	};

	msc_disk0 {
		compatible = "zephyr,flash-disk";
		partition = <&storage_partition>;
		disk-name = "NAND";
		cache-size = <4096>;
	};
};

Then a pm_static.yml added to the project as follows.

external_flash:
  address: 0x0
  end_address: 0x4000000
  size: 0x04000000
  device: mx25r64
  region: external_flash

storage_partition:
  address: 0x0
  device: DT_CHOSEN(nordic_pm_ext_flash)
  end_address: 0x400000
  placement:
    after:
    - start
  region: external_flash
  size: 0x0400000

With these changes the software now builds and runs but it seems to fetch the wrong partition in the mass example.

Area 2 at 0x10000 on flash-controller@39000 for 262144 bytes

partitions.yaml clearly adds the new partition

app:
  address: 0x0
  end_address: 0x100000
  region: flash_primary
  size: 0x100000
external_flash:
  address: 0x0
  device: mx25r64
  end_address: 0x4000000
  region: external_flash
  size: 0x4000000
otp:
  address: 0xff8100
  end_address: 0xff83fc
  region: otp
  size: 0x2fc
sram_primary:
  address: 0x20000000
  end_address: 0x20080000
  region: sram_primary
  size: 0x80000
storage_partition:
  address: 0x0
  device: DT_CHOSEN(nordic_pm_ext_flash)
  end_address: 0x400000
  placement:
    after:
    - start
  region: external_flash
  size: 0x400000

The generated devicetree states partitions on the qspi driver

 *   11  /soc/peripheral@50000000
 *   12  /soc/peripheral@50000000/qspi@2b000
 *   13  /soc/peripheral@50000000/qspi@2b000/mx25r6435f@0
 *   14  /soc/peripheral@50000000/qspi@2b000/mx25r6435f@0/partitions
 *   15  /soc/peripheral@50000000/qspi@2b000/mx25r6435f@0/partitions/partition@0
 ....
  *   129 /soc/peripheral@50000000/flash-controller@39000
 *   130 /soc/peripheral@50000000/flash-controller@39000/flash@0
 *   131 /soc/peripheral@50000000/flash-controller@39000/flash@0/partitions
 *   132 /soc/peripheral@50000000/flash-controller@39000/flash@0/partitions/partition@0
 *   133 /soc/peripheral@50000000/flash-controller@39000/flash@0/partitions/partition@10000
 *   134 /soc/peripheral@50000000/flash-controller@39000/flash@0/partitions/partition@50000
 *   135 /soc/peripheral@50000000/flash-controller@39000/flash@0/partitions/partition@80000
 *   136 /soc/peripheral@50000000/flash-controller@39000/flash@0/partitions/partition@c0000