Trying to write external flash with SDK 2.2.0

RE: Trying to write external flash with SDK 2.2.0

Randall — Tue, 28 Feb 2023 15:54:42 GMT

OK, that worked. I copied partiions.yaml to the file pm_static.yml in my project directory. Edited it to make a portion of my app memory be a stand along partition in the tfm non-secure space and I was able to use it as a writable flash section without screwing up the bootloader.

So we can mark this as complete. Thanks.

RE: Trying to write external flash with SDK 2.2.0

variant — Tue, 28 Feb 2023 13:51:05 GMT

There's info on that file here. It might be worthwhile to peruse the entire discussion of the Partition Manager

RE: Trying to write external flash with SDK 2.2.0

Randall — Tue, 28 Feb 2023 13:45:14 GMT

No. My project is the serial_lte_modem example. So I have everything that is in that application. Is there any description of the use of this file that I can use to create new partitions?

RE: Trying to write external flash with SDK 2.2.0

variant — Tue, 28 Feb 2023 13:42:59 GMT

Do you have a pm_static.yml file in your project top-level directory?

RE: Trying to write external flash with SDK 2.2.0

Randall — Tue, 28 Feb 2023 13:34:21 GMT

Can you give me information about how to redefine the memory partitions. the partitions.yaml file is in the build directory and I can't find the source files that are used it creating it. I need to be able to change the parition table.

RE: Trying to write external flash with SDK 2.2.0

Randall — Tue, 28 Feb 2023 13:33:01 GMT

This is already enabled for my application

RE: Trying to write external flash with SDK 2.2.0

Amanda Hsieh — Tue, 28 Feb 2023 13:28:27 GMT

Hi,

Try to enable CONFIG_MPU_ALLOW_FLASH_WRITE for instance.

-Amanda H.

RE: Trying to write external flash with SDK 2.2.0

Randall — Tue, 28 Feb 2023 13:27:35 GMT

Contining self discovery since I'm not getting any responses, I was able to get internal flash erase/writing working by definiing a const variable in the application that is aligned on a 32k byte boundary. The problem is, that since I'm changing the contents of the application space. The problem with this is that it changes the app image in flash and the bootloader no longer considers it a bootable image. So I need to either be able to figure out how to take out a segment of the app image and define it as a new, non-secure flash partition, or change the bootloader not to do the validation test. Can you help me with either of these?

Randall

RE: Trying to write external flash with SDK 2.2.0

Randall — Mon, 27 Feb 2023 13:45:31 GMT

I just realized that I mistittled this ticket. I'm not trying to write external flash, but internal flash.

I've been looking at partitions.yml to try to figure things out. It looks like this section is now defined;

EMPTY_2:

address: 0xf0000

end_address: 0xf8000

placement:

after:

- mcuboot_secondary

region: flash_primary

size: 0x8000

That used to be the scratch image in the pre 2.x SDKs. I combined the scratch and the storage partitions in my old builds because I needed 64K of internal storage for my application. Is there anyway to define a 64k chunk somewhere that can be setup an non_secure?

RE: Trying to write external flash with SDK 2.2.0

Randall — Fri, 24 Feb 2023 15:40:50 GMT

I have no idea what uart1 has to do with all of this. I'm trying to write to flash.

I'm getting my flash device like this; flashDev = DEVICE_DT_GET(DT_CHOSEN(zephyr_flash_controller));

Then I'm trying to erase like this; err = flash_erase( flashDev, FLASH_BIN_OFFSET, FLASH_BIN_SIZE ))

Where FLASH_BIN_OFFSET = 0xF0000 (the start of the scratch_partition) and SIZE is the size of the partition.

When the erase code gets to the following line; *(volatile uint32_t *)page_addr = 0xFFFFFFFF; in file nrf_nvmc.h of the inline function nrf_nvmc_page_erase_start, it immediately goes to the C_SecureFault_Handler in faults.c

and page_addr = 0xF0000, so it's as it should be.

Randall

RE: Trying to write external flash with SDK 2.2.0

Amanda Hsieh — Fri, 24 Feb 2023 15:05:00 GMT

Hi,

In NCS, we use the Partition Manager, not the device tree to partition the flash. The Partition Manager is enabled automatically in multi-image builds (such as when you build for non-secure, and get TF-M automatically)

Which peripheral instance do you use to communicate with the flash?

We have always used the Partition Manager, but we switched to TF-M somewhere around 2.0.0. And TF-M by default takes control over UART1

Regards,
Amanda H.

RE: Trying to write external flash with SDK 2.2.0

Randall — Fri, 24 Feb 2023 14:11:02 GMT

OK. well by using;

flashDev = DEVICE_DT_GET(DT_CHOSEN(zephyr_flash_controller));

Seems to work. But then when I try to erase sectors in there I get a security violation. I've tried to update my _ns .dts to add the scratch partiion;

chosen {

zephyr,flash = &flash0;

zephyr,sram = &sram0_ns;

zephyr,code-partition = &slot0_ns_partition;

zephyr,scratch-partition = &scratch_partition;

};

But I still get the security violation. I'm trying ot figure out how to get this partition configured so that I can erase/write it from my non-secure app.

Thanks.

RE: Trying to write external flash with SDK 2.2.0

Amanda Hsieh — Fri, 24 Feb 2023 13:51:24 GMT

Hi,

device_get_binding() is indeed deprecated since v2.0.0, see this issue: https://github.com/zephyrproject-rtos/zephyr/issues/43230.

Regards,
Amanda H.