owner-nrf52sdk/nRF5_SDK_17.0.2/modules/nrfx/mdk/system_nrf52805.c

/*

Copyright (c) 2009-2020 ARM Limited. All rights reserved.

    SPDX-License-Identifier: Apache-2.0

Licensed under the Apache License, Version 2.0 (the License); you may
not use this file except in compliance with the License.
You may obtain a copy of the License at

    www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an AS IS BASIS, WITHOUT
WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

NOTICE: This file has been modified by Nordic Semiconductor ASA.

*/

/* NOTE: Template files (including this one) are application specific and therefore expected to
   be copied into the application project folder prior to its use! */

#include <stdint.h>
#include <stdbool.h>
#include "nrf.h"
#include "nrf_erratas.h"
#include "system_nrf52805.h"

/*lint ++flb "Enter library region" */

#define __SYSTEM_CLOCK_64M      (64000000UL)

#if defined ( __CC_ARM )
    uint32_t SystemCoreClock __attribute__((used)) = __SYSTEM_CLOCK_64M;
#elif defined ( __ICCARM__ )
    __root uint32_t SystemCoreClock = __SYSTEM_CLOCK_64M;
#elif defined ( __GNUC__ )
    uint32_t SystemCoreClock __attribute__((used)) = __SYSTEM_CLOCK_64M;
#endif

void SystemCoreClockUpdate(void)
{
    SystemCoreClock = __SYSTEM_CLOCK_64M;
}

void SystemInit(void)
{
    /* Workaround for Errata 31 "CLOCK: Calibration values are not correctly loaded from FICR at reset" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/index.jsp */
    if (nrf52_errata_31()){
        *(volatile uint32_t *)0x4000053C = ((*(volatile uint32_t *)0x10000244) & 0x0000E000) >> 13;
    }

    /* Workaround for Errata 36 "CLOCK: Some registers are not reset when expected" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/index.jsp  */
    if (nrf52_errata_36()){
        NRF_CLOCK->EVENTS_DONE = 0;
        NRF_CLOCK->EVENTS_CTTO = 0;
        NRF_CLOCK->CTIV = 0;
    }
    
    /* Workaround for Errata 66 "TEMP: Linearity specification not met with default settings" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/index.jsp  */
    if (nrf52_errata_66()){
        NRF_TEMP->A0 = NRF_FICR->TEMP.A0;
        NRF_TEMP->A1 = NRF_FICR->TEMP.A1;
        NRF_TEMP->A2 = NRF_FICR->TEMP.A2;
        NRF_TEMP->A3 = NRF_FICR->TEMP.A3;
        NRF_TEMP->A4 = NRF_FICR->TEMP.A4;
        NRF_TEMP->A5 = NRF_FICR->TEMP.A5;
        NRF_TEMP->B0 = NRF_FICR->TEMP.B0;
        NRF_TEMP->B1 = NRF_FICR->TEMP.B1;
        NRF_TEMP->B2 = NRF_FICR->TEMP.B2;
        NRF_TEMP->B3 = NRF_FICR->TEMP.B3;
        NRF_TEMP->B4 = NRF_FICR->TEMP.B4;
        NRF_TEMP->B5 = NRF_FICR->TEMP.B5;
        NRF_TEMP->T0 = NRF_FICR->TEMP.T0;
        NRF_TEMP->T1 = NRF_FICR->TEMP.T1;
        NRF_TEMP->T2 = NRF_FICR->TEMP.T2;
        NRF_TEMP->T3 = NRF_FICR->TEMP.T3;
        NRF_TEMP->T4 = NRF_FICR->TEMP.T4;
    }

    /* Workaround for Errata 136 "System: Bits in RESETREAS are set when they should not be" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/index.jsp  */
    if (nrf52_errata_136()){
        if (NRF_POWER->RESETREAS & POWER_RESETREAS_RESETPIN_Msk){
            NRF_POWER->RESETREAS =  ~POWER_RESETREAS_RESETPIN_Msk;
        }
    }
    
    /* Workaround for Errata 217 "RAM: RAM content cannot be trusted upon waking up from System ON Idle or System OFF mode" found at the Errata document
       for your device located at https://infocenter.nordicsemi.com/index.jsp  */
    if (nrf52_errata_217()){
        *(volatile uint32_t *)0x40000EE4ul |= 0x0000000Ful;
    }
    
    /* Configure GPIO pads as pPin Reset pin if Pin Reset capabilities desired. If CONFIG_GPIO_AS_PINRESET is not
      defined, pin reset will not be available. One GPIO (see Product Specification to see which one) will then be
      reserved for PinReset and not available as normal GPIO. */
    #if defined (CONFIG_GPIO_AS_PINRESET)

        #define RESET_PIN 21

        if (((NRF_UICR->PSELRESET[0] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos)) ||
            ((NRF_UICR->PSELRESET[1] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos))){
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->PSELRESET[0] = RESET_PIN;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_UICR->PSELRESET[1] = RESET_PIN;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
            NVIC_SystemReset();
        }
    #endif

    SystemCoreClockUpdate();
}


/*lint --flb "Leave library region" */