openblt/Target/Demo/ARMCM0_S32K11_S32K118EVB_GCC/Boot/lib/system_S32K118.c

/*
 * Copyright 2017-2018 NXP
 * All rights reserved.
 *
 * THIS SOFTWARE IS PROVIDED BY NXP "AS IS" AND ANY EXPRESSED OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL NXP OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * @page misra_violations MISRA-C:2012 violations
 *
 * @section [global]
 * Violates MISRA 2012 Advisory Rule 8.9, An object should be defined at block
 * scope if its identifier only appears in a single function.
 * An object with static storage duration declared at block scope cannot be
 * accessed directly from outside the block.
 *
 * @section [global]
 * Violates MISRA 2012 Advisory Rule 11.4, A conversion should not be performed
 * between a pointer to object and an integer type.
 * The cast is required to initialize a pointer with an unsigned int define,
 * representing an address.
 *
 * @section [global]
 * Violates MISRA 2012 Required Rule 11.6, A cast shall not be performed
 * between pointer to void and an arithmetic type.
 * The cast is required to initialize a pointer with an unsigned int define,
 * representing an address.
 *
 * @section [global]
 * Violates MISRA 2012 Advisory Rule 8.7, External could be made static.
 * Function is defined for usage by application code.
 *
 */

#include "device_registers.h"
#include "system_S32K118.h"
#include "stdbool.h"

/* ----------------------------------------------------------------------------
   -- Core clock
   ---------------------------------------------------------------------------- */

uint32_t SystemCoreClock = DEFAULT_SYSTEM_CLOCK;

/*FUNCTION**********************************************************************
 *
 * Function Name : SystemInit
 * Description   : This function disables the watchdog, enables FPU
 * and the power mode protection if the corresponding feature macro
 * is enabled. SystemInit is called from startup_device file.
 *
 * Implements    : SystemInit_Activity
 *END**************************************************************************/
void SystemInit(void)
{
/**************************************************************************/
/* WDOG DISABLE*/
/**************************************************************************/

#if (DISABLE_WDOG)
    /* Write of the WDOG unlock key to CNT register, must be done in order to allow any modifications*/
    WDOG->CNT = (uint32_t ) FEATURE_WDOG_UNLOCK_VALUE;
    /* The dummy read is used in order to make sure that the WDOG registers will be configured only
     * after the write of the unlock value was completed. */
    (void)WDOG->CNT;

    /* Initial write of WDOG configuration register:
     * enables support for 32-bit refresh/unlock command write words,
     * clock select from LPO, update enable, watchdog disabled */
    WDOG->CS  = (uint32_t ) ( (1UL << WDOG_CS_CMD32EN_SHIFT)                       |
                              (FEATURE_WDOG_CLK_FROM_LPO << WDOG_CS_CLK_SHIFT)     |
                              (0U << WDOG_CS_EN_SHIFT)                             |
                              (1U << WDOG_CS_UPDATE_SHIFT)                         );

    /* Configure timeout */
    WDOG->TOVAL = (uint32_t )0xFFFF;
#endif /* (DISABLE_WDOG) */
}

/*FUNCTION**********************************************************************
 *
 * Function Name : SystemCoreClockUpdate
 * Description   : This function must be called whenever the core clock is changed
 * during program execution. It evaluates the clock register settings and calculates
 * the current core clock.
 *
 * Implements    : SystemCoreClockUpdate_Activity
 *END**************************************************************************/
void SystemCoreClockUpdate(void)
{
    uint32_t SCGOUTClock = 0U;      /* Variable to store output clock frequency of the SCG module */
    uint32_t regValue;              /* Temporary variable */
    uint32_t divider;
    bool validSystemClockSource = true;

    divider = ((SCG->CSR & SCG_CSR_DIVCORE_MASK) >> SCG_CSR_DIVCORE_SHIFT) + 1U;

    switch ((SCG->CSR & SCG_CSR_SCS_MASK) >> SCG_CSR_SCS_SHIFT)
    {
        case 0x1:
            /* System OSC */
            SCGOUTClock = CPU_XTAL_CLK_HZ;
            break;
        case 0x2:
            /* Slow IRC */
            regValue = (SCG->SIRCCFG & SCG_SIRCCFG_RANGE_MASK) >> SCG_SIRCCFG_RANGE_SHIFT;
            if (regValue != 0UL)
            {
                SCGOUTClock = FEATURE_SCG_SIRC_HIGH_RANGE_FREQ;
            }
            else
            {
                validSystemClockSource = false;
            }
            break;
        case 0x3:
            /* Fast IRC */
            regValue = (SCG->FIRCCFG & SCG_FIRCCFG_RANGE_MASK) >> SCG_FIRCCFG_RANGE_SHIFT;
            if (regValue == 0x0UL)
            {
                SCGOUTClock = FEATURE_SCG_FIRC_FREQ0;
            }
            else
            {
                validSystemClockSource = false;
            }
            break;
        default:
            validSystemClockSource = false;
            break;
    }

    if (validSystemClockSource == true)
    {
        SystemCoreClock = (SCGOUTClock / divider);
    }
}

/*FUNCTION**********************************************************************
 *
 * Function Name : SystemSoftwareReset
 * Description   : This function is used to initiate a system reset
 *
 * Implements    : SystemSoftwareReset_Activity
 *END**************************************************************************/
void SystemSoftwareReset(void)
{
    uint32_t regValue;

    /* Read Application Interrupt and Reset Control Register */
    regValue = S32_SCB->AIRCR;

    /* Clear register key */
    regValue &= ~( S32_SCB_AIRCR_VECTKEY_MASK);

    /* Configure System reset request bit and Register Key */
    regValue |= S32_SCB_AIRCR_VECTKEY(FEATURE_SCB_VECTKEY);
    regValue |= S32_SCB_AIRCR_SYSRESETREQ(0x1u);

    /* Write computed register value */
    S32_SCB->AIRCR = regValue;
}

/*******************************************************************************
 * EOF
 ******************************************************************************/