partial erase vs BLE stack

Question

Hello,

I have been developed a log system in the internal flash. To do that I have been using the nrf storage library.

My first problem came up when I tried to use nrf_fstorage_erase for one single page; this operation is blocking the interrupts of some sensors, so I am losing some data. I calculated how much was the elapsed time during which I am blocked and I obtained around 150 ms (which is higher than the 85 ms that I found for a single page erase in the datasheet) which is strange to me.

As I cannot afford to lose the data during 150 ms, I have checked the partial erase feature. Following this idea, I developed the following function:

static void partial_erase(nrf_fstorage_t const* p_fstorage, uint32_t p_flash_start, uint32_t num_pages)
{
    ret_code_t err_code;
    
    /* Check that the address and size are aligned to the flash page size */
    if (p_flash_start % FLASH_PAGE_SIZE) {
        /* Handle unaligned address or size */
    }
  
    /* Enable the write access to the flash */
    NRF_NVMC->CONFIG = (NVMC_CONFIG_WEN_Een << NVMC_CONFIG_WEN_Pos);
        
    /* Configure the partial erase duration */
    NRF_NVMC->ERASEPAGEPARTIALCFG = PARTIAL_ERASE_TIME_MS;

    /* Erase the specified number of pages */
    for (uint32_t i = 0; i < num_pages; i++) {
        /* Calculate the address of the page to erase */
        uint32_t page_address = p_flash_start + (i * FLASH_PAGE_SIZE);
    
        /* Specify the address of the page to partially erase */
        NRF_NVMC->ERASEPAGEPARTIAL = page_address;

        /* Wait for the erase operation to complete */
        while (NRF_NVMC->READY == NVMC_READY_READY_Busy);
//        wait_for_flash_ready(&fstorage);
    }
    
    /* Disable the write access to the flash */
    NRF_NVMC->CONFIG = (NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos);
}

The problem here is that it looks incompatible with the parallel execution of BLE stack.

I got into the function "app_error_fault_handler" right after the execution of the line:

NRF_NVMC->CONFIG = (NVMC_CONFIG_WEN_Een << NVMC_CONFIG_WEN_Pos);

My understanding is that there is some conflict with the parallel BLE execution and partial erase, so I updated my function disabling/enabling temporarily the ble stack in this way:

static void pause_ble()
{
    nrf_sdh_disable_request();  
}

static void resume_ble()
{
    nrf_sdh_enable_request();

    // Wait for SoftDevice to be enabled
    while (!nrf_sdh_is_enabled()) {
         __WFE();
    }
    
    // Wait for HFCLK to be started
    while (nrf_clock_hf_is_running(NRF_CLOCK_HFCLK_HIGH_ACCURACY) != true) {}
}

static void partial_erase(nrf_fstorage_t const* p_fstorage, uint32_t p_flash_start, uint32_t num_pages)
{
    ret_code_t err_code;
    
    /* Check that the address and size are aligned to the flash page size */
    if (p_flash_start % FLASH_PAGE_SIZE) {
        /* Handle unaligned address or size */
    }

    pause_ble();
  
    /* Enable the write access to the flash */
    NRF_NVMC->CONFIG = (NVMC_CONFIG_WEN_Een << NVMC_CONFIG_WEN_Pos);
        
    /* Configure the partial erase duration */
    NRF_NVMC->ERASEPAGEPARTIALCFG = PARTIAL_ERASE_TIME_MS;

    /* Erase the specified number of pages */
    for (uint32_t i = 0; i < num_pages; i++) {
        /* Calculate the address of the page to erase */
        uint32_t page_address = p_flash_start + (i * FLASH_PAGE_SIZE);
    
        /* Specify the address of the page to partially erase */
        NRF_NVMC->ERASEPAGEPARTIAL = page_address;

        /* Wait for the erase operation to complete */
        while (NRF_NVMC->READY == NVMC_READY_READY_Busy);
//        wait_for_flash_ready(&fstorage);
    }
    
    /* Disable the write access to the flash */
    NRF_NVMC->CONFIG = (NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos);      
    
    resume_ble();
}

After this modification, I got another issue: BLE_ERROR_NOT_ENABLED after the interrupt SWI2_EGU2_IRQn is triggered. It looks like there is some BLE operation before the BLE stack is enabled, but I don't know how to prevent the SWI2_EGU2_IRQn to raise in order to avoid the error.

Could you please provide me some suggestions or corrections of my code to make partial erase and BLE stack working?

Thanks!