Programming and reading OTP

RE: Programming and reading OTP

Håkon Alseth — Mon, 13 Jan 2025 10:03:44 GMT

Hi,

This was introduced in v2.8.0:

[quote user="hkn"]

TFM has support for accessing UICR from a non-secure application in ncs main:

https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/libraries/security/tfm/tfm_ioctl_api.html#read_service

[/quote]

so if you are on an older version, it will not work.

[quote user="jpnorair"]Alternate possibility is to create a separate block of flash that is reserved for configuration constants. This would normally take 5 minutes to edit linker script, but with Zephyr everything is harder -- do you have a help page for how to get a reserved flash block in zephyr that gets into the linker script as a section? For example, in order to do something like:[/quote]

This thread shows how to add a linker section (although it is for a RAM region):

RE: CONFIG_CUSTOM_LINKER_SCRIPT in prj.conf not working.

If you still run into issues, please consider to create a dedicated thread wrt. your matter.

Kind regards,

Håkon

RE: Programming and reading OTP

jpnorair — Sat, 11 Jan 2025 14:47:35 GMT

I am using this method, still without success (result is same as from original post, error code = 2).

The configuration file complains about prerequisites to CONFIG_TFM_PARTITION_PLATFORM

I have a system with nrf91, the modem core running modem stuff, mcuboot on the application core, and then the application image. I need to access OTP in the application (for read only), but I don't know how to set it up so that it works.

Alternate possibility is to create a separate block of flash that is reserved for configuration constants. This would normally take 5 minutes to edit linker script, but with Zephyr everything is harder -- do you have a help page for how to get a reserved flash block in zephyr that gets into the linker script as a section? For example, in order to do something like:

 const uint8_t serial_number[] __attribute__((section(".my_serial_number")))

RE: Programming and reading OTP

Håkon Alseth — Fri, 23 Aug 2024 07:43:14 GMT

TFM has support for accessing UICR from a non-secure application in ncs main:

https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/libraries/security/tfm/tfm_ioctl_api.html#read_service

Kind regards,

Håkon

RE: Programming and reading OTP

Håkon Alseth — Mon, 08 Jan 2024 14:26:46 GMT

Hi Bob,

Unfortunately, the support is not implemented in TF-M, so accessing UICR from the non-secure application must be manually implemented by adding the range as described below.

Kind regards,

Håkon

RE: Programming and reading OTP

bobkressin — Sun, 07 Jan 2024 03:19:13 GMT

Hey Håkon -

Have you any update on this issue regarding UICR access via TF-M? We are now in a similar situation. Thank you for advising.

Kind Regards,

- Bob

RE: Programming and reading OTP

hugzy123 — Wed, 23 Aug 2023 10:17:19 GMT

We're also wanting to use this functionality for our product

RE: Programming and reading OTP

Håkon Alseth — Tue, 25 Apr 2023 11:30:38 GMT

Hi,

Unfortunately, this is not yet implemented on our side.

One can add ranges by appending this array: https://github.com/nrfconnect/sdk-trusted-firmware-m/blob/v1.6.0-ncs3/platform/ext/target/nordic_nrf/nrf9160dk_nrf9160/services/include/tfm_read_ranges.h#L25

But, please note that due to errata #160 for nRF9160, this function needs to be patched with a similar workaround (as I posted here: RE: Error reading UICR->OTP registers in SDK 1.9.1 (result is 0xdeaddead) ) :

https://github.com/nrfconnect/sdk-trusted-firmware-m/blob/v1.6.0-ncs3/platform/ext/target/nordic_nrf/common/core/services/src/tfm_platform_hal_ioctl.c#L57

Which is effectively a call to memcpy:

https://github.com/nrfconnect/sdk-trusted-firmware-m/blob/v1.6.0-ncs3/secure_fw/spm/include/tfm_memory_utils.h#L24-L27

Kind regards,

Håkon

RE: Programming and reading OTP

pf7 — Mon, 24 Apr 2023 10:12:10 GMT

Hello Håkon,

is there any update on this issue? It seems not very professional to default to TF-M if such an important feature is not implemented yet.

Best regards,

Patrick

RE: Programming and reading OTP

Oskar — Mon, 27 Mar 2023 11:55:46 GMT

I want to bump this as well, I am working on a project where we would like to use the OTP to ensure read-only data. Are there any updates on this fix?

RE: Programming and reading OTP

Håkon Alseth — Tue, 31 Jan 2023 12:33:56 GMT

Hi,

Unfortunately, the task is not yet addressed, but I will address your comment to the team.

Kind regards,

Håkon

RE: Programming and reading OTP

gjoasen — Tue, 31 Jan 2023 12:08:45 GMT

Hi,

Any update on when we can hope to see reading UICR supported in TFM?

RE: Programming and reading OTP

Håkon Alseth — Tue, 06 Dec 2022 15:16:42 GMT

Hi,

My apologies for the inconvenience. The feature request has not yet been implemented. I will add your comments to the internal task.

At this moment, since there is no added logic for reading UICR in TFM, it has to be stored in another place, for instance in a settings page (using for instance nvs) in flash.

Kind regards,

Håkon

RE: Programming and reading OTP

allard.p — Fri, 02 Dec 2022 10:56:47 GMT

Still working on this. If I understand correctly: Reading UICR is only allowed from secure code. TF-M is now the default in SDK 2.1.0, but it has no way to read the OTP area, so UICR is now useless for storing user data?

What way does Nordic suggest to store non-changeable data such as a serial number?

RE: Programming and reading OTP

allard.p — Tue, 18 Oct 2022 07:05:33 GMT

Thank you, I will wait for this feature, in the meantime I'll come up with another solution.

RE: Programming and reading OTP

Håkon Alseth — Mon, 17 Oct 2022 13:56:08 GMT

Hi,

Reading from UICR is currently not supported using TF-M, but I have inputted a feature request for this internally.

For the nRF9160, there's an errata when reading UICR and the mainblock, which needs a specific patch in TF-M handling:

https://infocenter.nordicsemi.com/topic/errata_nRF9160_Rev2/ERR/nRF9160/Rev2/latest/anomaly_160_7.html?cp=2_0_1_0_1_4

If you are using SPM, there's logic for reading UICR region here that handles the scenario:

https://devzone.nordicsemi.com/support-private/support/289023#permalink=758929

Kind regards,

Håkon