How can I read the UICR register of 9160?

[xinjiang]

The current project needs to save the ID in the programmable register and use the ID in the application image.

So I save the ID number in the URCI->OTP[0] register. When I read the ID in URCI->OTP[0] in the main function of the application image, a fatal error occurred.

uint32_t get_id_from_uicr(){
        uint32_t id;
        id = (NRF_UICR_S->OTP[0]);
        return id;
}

As far as I know, UICR can only be read in secure code.

So I execute this code in the main function of spm and get the ID normally. How can I pass the ID to the application image(not via flash)?

Or is there any other better way to store this ID?

spm.c:

uint32_t get_id_from_uicr(){
        uint32_t id;
        id = (NRF_UICR_S->OTP[0]);
        return id;
}

void main(void)
{
    uint32_t id;
    id = get_imei_from_uicr();
	spm_config();
	spm_jump();
}

[flaik-wayne]

Hi xinjiang - the problem is that OTP memory must be read in 32 bit words. Simply adding the OTP memory to the `ranges` in spm_request_read_nse isn't enough - I used code like this:

__TZ_NONSECURE_ENTRY_FUNC
int spm_request_read_nse(void *destination, uint32_t addr, size_t len)
{
	static const struct read_range ranges[] = {

#ifdef PM_MCUBOOT_ADDRESS
		/* Allow reads of mcuboot metadata */
		{.start = PM_MCUBOOT_PAD_ADDRESS,
		 .size = PM_MCUBOOT_PAD_SIZE},
#endif
		{.start = FICR_INFO_ADDR,
		 .size = FICR_INFO_SIZE},
#if defined(FICR_NFC_TAGHEADER0_MFGID_Msk)
		{.start = FICR_NFC_ADDR,
		 .size = FICR_NFC_SIZE},
#endif
		{.start = FICR_RESTRICTED_ADDR,
		 .size = FICR_RESTRICTED_SIZE},

        // Allow reading UICR
        {.start = NRF_UICR_S_BASE,
         .size = 4096},
	};

	if (destination == NULL || len <= 0) {
		return -EINVAL;
	}

	if (ptr_in_secure_area((intptr_t)destination)) {
		return -EINVAL;
	}

	for (size_t i = 0; i < ARRAY_SIZE(ranges); i++) {
		uint32_t start = ranges[i].start;
		uint32_t size = ranges[i].size;

		if (addr >= start && addr + len <= start + size)
        {
            if ((addr & 3) == 0 && (len & 3) == 0)
            {
                // use 32 bit copy
                uint32_t *d = destination;
                uint32_t *s = (uint32_t)addr;
                while (len)
                {
                    *d++ = *s++;
                    len -= 4;
                }
            }
            else
            {
			    memcpy(destination, (const void *)addr, len);
            }
			return 0;
		}
	}

	return -EPERM;
}