/*
** ###################################################################
**     Compilers:           Keil ARM C/C++ Compiler
**                          Freescale C/C++ for Embedded ARM
**                          GNU C Compiler
**                          GNU C Compiler - CodeSourcery Sourcery G++
**                          IAR ANSI C/C++ Compiler for ARM
**
**     Reference manual:    MKW40Z160RM, Rev. 1.1, 4/2015
**     Version:             rev. 1.2, 2015-05-07
**     Build:               b150513
**
**     Abstract:
**         Provides a system configuration function and a global variable that
**         contains the system frequency. It configures the device and initializes
**         the oscillator (PLL) that is part of the microcontroller device.
**
**     Copyright (c) 2015 Freescale Semiconductor, Inc.
**     All rights reserved.
**
**     Redistribution and use in source and binary forms, with or without modification,
**     are permitted provided that the following conditions are met:
**
**     o Redistributions of source code must retain the above copyright notice, this list
**       of conditions and the following disclaimer.
**
**     o Redistributions in binary form must reproduce the above copyright notice, this
**       list of conditions and the following disclaimer in the documentation and/or
**       other materials provided with the distribution.
**
**     o Neither the name of Freescale Semiconductor, Inc. nor the names of its
**       contributors may be used to endorse or promote products derived from this
**       software without specific prior written permission.
**
**     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
**     ANY EXPRESS 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 THE COPYRIGHT HOLDER OR 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.
**
**     http:                 www.freescale.com
**     mail:                 support@freescale.com
**
**     Revisions:
**     - rev. 1.0 (2014-08-27)
**         Initial version.
**     - rev. 1.1 (2015-03-05)
**         Update with reference manual rev 1.0
**     - rev. 1.2 (2015-05-07)
**         Update with reference manual rev 1.1
**
** ###################################################################
*/

/*!
 * @file MKW20Z4
 * @version 1.2
 * @date 2015-05-07
 * @brief Device specific configuration file for MKW20Z4 (implementation file)
 *
 * Provides a system configuration function and a global variable that contains
 * the system frequency. It configures the device and initializes the oscillator
 * (PLL) that is part of the microcontroller device.
 */

#include <stdint.h>
#include "fsl_device_registers.h"



/* ----------------------------------------------------------------------------
   -- Core clock
   ---------------------------------------------------------------------------- */

uint32_t SystemCoreClock = DEFAULT_SYSTEM_CLOCK;

/* ----------------------------------------------------------------------------
   -- SystemInit()
   ---------------------------------------------------------------------------- */

void SystemInit (void) {

#if (DISABLE_WDOG)
  /* SIM_COPC: COPT=0,COPCLKS=0,COPW=0 */
  SIM->COPC = (uint32_t)0x00u;
#endif /* (DISABLE_WDOG) */
#ifdef CLOCK_SETUP
  if((RCM->SRS0 & RCM_SRS0_WAKEUP_MASK) != 0x00U)
  {
    if((PMC->REGSC & PMC_REGSC_ACKISO_MASK) != 0x00U)
    {
       PMC->REGSC |= PMC_REGSC_ACKISO_MASK; /* Release hold with ACKISO:  Only has an effect if recovering from VLLSx.*/
    }
  } else {
#ifdef SYSTEM_RTC_CR_VALUE
    SIM->SCGC5 |= SIM_SCGC5_PORTB_MASK;
    SIM_SCGC6 |= SIM_SCGC6_RTC_MASK;
    /* PORTB_PCR18: ISF=0,MUX=0 */
    PORTB->PCR[16] &= (uint32_t)~(uint32_t)((PORT_PCR_ISF_MASK | PORT_PCR_MUX(0x07)));
    /* PORTA_PCR19: ISF=0,MUX=0 */
    PORTB->PCR[17] &= (uint32_t)~(uint32_t)((PORT_PCR_ISF_MASK | PORT_PCR_MUX(0x07)));
    if ((RTC->CR & RTC_CR_OSCE_MASK) == 0x00U) { /* Only if the OSCILLATOR is not already enabled */
      RTC->CR = (uint32_t)((RTC_CR & (uint32_t)~(uint32_t)(RTC_CR_SC2P_MASK | RTC_CR_SC4P_MASK | RTC_CR_SC8P_MASK | RTC_CR_SC16P_MASK)) | (uint32_t)SYSTEM_RTC_CR_VALUE);
      RTC->CR |= (uint32_t)RTC_CR_OSCE_MASK;
      RTC->CR &= (uint32_t)~(uint32_t)RTC_CR_CLKO_MASK;
    }
#endif
  }

  /* Power mode protection initialization */
#ifdef SYSTEM_SMC_PMPROT_VALUE
  SMC->PMPROT = SYSTEM_SMC_PMPROT_VALUE;
#endif

  /* RF oscillator setting */
#if defined(SYSTEM_RSIM_CONTROL_VALUE)
  RSIM->CONTROL = SYSTEM_RSIM_CONTROL_VALUE;
#endif

  /* System clock initialization */
  /* Internal reference clock trim initialization */
#if defined(SLOW_TRIM_ADDRESS)
  if ( *((uint8_t*)SLOW_TRIM_ADDRESS) != 0xFFU) { /* Skip if non-volatile flash memory is erased */
    MCG->C3 = *((uint8_t*)SLOW_TRIM_ADDRESS);
#endif /* defined(SLOW_TRIM_ADDRESS) */
#if defined(SLOW_FINE_TRIM_ADDRESS)
    MCG->C4 = (MCG->C4 & ~(MCG_C4_SCFTRIM_MASK)) | ((*((uint8_t*) SLOW_FINE_TRIM_ADDRESS)) & MCG_C4_SCFTRIM_MASK);
#endif
#if defined(FAST_TRIM_ADDRESS)
    MCG->C4 = (MCG->C4 & ~(MCG_C4_FCTRIM_MASK)) |((*((uint8_t*) FAST_TRIM_ADDRESS)) & MCG_C4_FCTRIM_MASK);
#endif
#if defined(FAST_FINE_TRIM_ADDRESS)
    MCG->C2 = (MCG->C2 & ~(MCG_C2_FCFTRIM_MASK)) | ((*((uint8_t*)FAST_TRIM_ADDRESS)) & MCG_C2_FCFTRIM_MASK);
#endif /* defined(FAST_FINE_TRIM_ADDRESS) */
#if defined(SLOW_TRIM_ADDRESS)
  }
#endif /* defined(SLOW_TRIM_ADDRESS) */

  /* Set system prescalers and clock sources */
  SIM->CLKDIV1 = SYSTEM_SIM_CLKDIV1_VALUE; /* Set system prescalers */
  SIM->SOPT1 = ((SIM->SOPT1) & (uint32_t)(~(SIM_SOPT1_OSC32KSEL_MASK))) | ((SYSTEM_SIM_SOPT1_VALUE) & (SIM_SOPT1_OSC32KSEL_MASK)); /* Set 32 kHz clock source (ERCLK32K) */
  SIM->SOPT2 = ((SIM->SOPT2) & (uint32_t)(~(SIM_SOPT2_TPMSRC_MASK))) | ((SYSTEM_SIM_SOPT2_VALUE) & (SIM_SOPT2_TPMSRC_MASK)); /* Selects the clock source for the TPM counter clock. */
#if ((MCG_MODE == MCG_MODE_FEI) || (MCG_MODE == MCG_MODE_FBI) || (MCG_MODE == MCG_MODE_BLPI))
  /* Set MCG */
  MCG->SC = SYSTEM_MCG_SC_VALUE;       /* Set SC (fast clock internal reference divider) */
  MCG->C1 = SYSTEM_MCG_C1_VALUE;       /* Set C1 (clock source selection, FLL ext. reference divider, int. reference enable etc.) */
  /* Check that the source of the FLL reference clock is the requested one. */
  if (((SYSTEM_MCG_C1_VALUE) & MCG_C1_IREFS_MASK) != 0x00U) {
    while((MCG->S & MCG_S_IREFST_MASK) == 0x00U) {
    }
  } else {
    while((MCG->S & MCG_S_IREFST_MASK) != 0x00U) {
    }
  }
  MCG->C2 = (MCG->C2 & (uint8_t)(~(MCG_C2_FCFTRIM_MASK))) | (SYSTEM_MCG_C2_VALUE & (uint8_t)(~(MCG_C2_LP_MASK))); /* Set C2 (freq. range, ext. and int. reference selection etc. excluding trim bits; low power bit is set later) */
  MCG->C4 = ((SYSTEM_MCG_C4_VALUE) & (uint8_t)(~(MCG_C4_FCTRIM_MASK | MCG_C4_SCFTRIM_MASK))) | (MCG->C4 & (MCG_C4_FCTRIM_MASK | MCG_C4_SCFTRIM_MASK)); /* Set C4 (FLL output; trim values not changed) */
  MCG->C7 = SYSTEM_MCG_C7_VALUE;       /* Set C7 (OSC Clock Select) */
  #if (MCG_MODE == MCG_MODE_BLPI)
  /* BLPI specific */
  MCG->C2 |= (MCG_C2_LP_MASK);         /* Disable FLL and PLL in bypass mode */
  #endif

#else /* MCG_MODE */
  /* Set MCG */
  MCG->SC = SYSTEM_MCG_SC_VALUE;       /* Set SC (fast clock internal reference divider) */
  MCG->C2 = (MCG->C2 & (uint8_t)(~(MCG_C2_FCFTRIM_MASK))) | (SYSTEM_MCG_C2_VALUE & (uint8_t)(~(MCG_C2_LP_MASK))); /* Set C2 (freq. range, ext. and int. reference selection etc. excluding trim bits; low power bit is set later) */
  MCG->C7 = SYSTEM_MCG_C7_VALUE;       /* Set C7 (OSC Clock Select) */
  MCG->C1 = SYSTEM_MCG_C1_VALUE;       /* Set C1 (clock source selection, FLL ext. reference divider, int. reference enable etc.) */
  /* Check that the source of the FLL reference clock is the requested one. */
  if (((SYSTEM_MCG_C1_VALUE) & MCG_C1_IREFS_MASK) != 0x00U) {
    while((MCG->S & MCG_S_IREFST_MASK) == 0x00U) {
    }
  } else {
    while((MCG->S & MCG_S_IREFST_MASK) != 0x00U) {
    }
  }
  MCG->C4 = ((SYSTEM_MCG_C4_VALUE)  & (uint8_t)(~(MCG_C4_FCTRIM_MASK | MCG_C4_SCFTRIM_MASK))) | (MCG->C4 & (MCG_C4_FCTRIM_MASK | MCG_C4_SCFTRIM_MASK)); /* Set C4 (FLL output; trim values not changed) */
#endif /* MCG_MODE */

  /* Common for all modes */

  MCG->C6 = (SYSTEM_MCG_C6_VALUE); /* Set C6 (Clock monitor enable) */
#if ((MCG_MODE == MCG_MODE_BLPI) || (MCG_MODE == MCG_MODE_BLPE))
  MCG->C2 |= (MCG_C2_LP_MASK);         /* Disable FLL in bypass mode */
#endif
#if ((MCG_MODE == MCG_MODE_FEI) || (MCG_MODE == MCG_MODE_FEE))
  while((MCG->S & MCG_S_CLKST_MASK) != 0x00U) { /* Wait until output of the FLL is selected */
  }
#elif ((MCG_MODE == MCG_MODE_FBI) || (MCG_MODE == MCG_MODE_BLPI))
  while((MCG->S & MCG_S_CLKST_MASK) != 0x04U) { /* Wait until internal reference clock is selected as MCG output */
  }
#elif ((MCG_MODE == MCG_MODE_FBE) || (MCG_MODE == MCG_MODE_BLPE))
  while((MCG->S & MCG_S_CLKST_MASK) != 0x08U) { /* Wait until external reference clock is selected as MCG output */
  }
#endif
#if (((SYSTEM_SMC_PMCTRL_VALUE) & SMC_PMCTRL_RUNM_MASK) == (0x02U << SMC_PMCTRL_RUNM_SHIFT))
  SMC->PMCTRL = (uint8_t)((SYSTEM_SMC_PMCTRL_VALUE) & (SMC_PMCTRL_RUNM_MASK)); /* Enable VLPR mode */
  while(SMC->PMSTAT != 0x04U) {        /* Wait until the system is in VLPR mode */
  }
#endif
#endif
}

/* ----------------------------------------------------------------------------
   -- SystemCoreClockUpdate()
   ---------------------------------------------------------------------------- */

void SystemCoreClockUpdate (void) {

  uint32_t MCGOUTClock;                /* Variable to store output clock frequency of the MCG module */
  uint16_t Divider;

  if ((MCG->C1 & MCG_C1_CLKS_MASK) == 0x00U) {
    /* FLL is selected */
    if ((MCG->C1 & MCG_C1_IREFS_MASK) == 0x00U) {
      /* External reference clock is selected */
      if((MCG->C7 & MCG_C7_OSCSEL_MASK) == 0x00U) {
        MCGOUTClock = CPU_XTAL_CLK_HZ; /* System oscillator drives MCG clock */
      } else {
        MCGOUTClock = CPU_XTAL32k_CLK_HZ; /* RTC 32 kHz oscillator drives MCG clock */
      }
      if (((MCG->C2 & MCG_C2_RANGE_MASK) != 0x00U) && ((MCG->C7 & MCG_C7_OSCSEL_MASK) != 0x01U)) {
        switch (MCG->C1 & MCG_C1_FRDIV_MASK) {
        case 0x38U:
          Divider = 1536U;
          break;
        case 0x30U:
          Divider = 1280U;
          break;
        default:
          Divider = (uint16_t)(32LU << ((MCG->C1 & MCG_C1_FRDIV_MASK) >> MCG_C1_FRDIV_SHIFT));
          break;
        }
      } else {/* ((MCG->C2 & MCG_C2_RANGE_MASK) != 0x00U) */
        Divider = (uint16_t)(1LU << ((MCG->C1 & MCG_C1_FRDIV_MASK) >> MCG_C1_FRDIV_SHIFT));
      }
      MCGOUTClock = (MCGOUTClock / Divider); /* Calculate the divided FLL reference clock */
    } else { /* (!((MCG->C1 & MCG_C1_IREFS_MASK) == 0x00U)) */
      MCGOUTClock = CPU_INT_SLOW_CLK_HZ; /* The slow internal reference clock is selected */
    } /* (!((MCG->C1 & MCG_C1_IREFS_MASK) == 0x00U)) */
    /* Select correct multiplier to calculate the MCG output clock  */
    switch (MCG->C4 & (MCG_C4_DMX32_MASK | MCG_C4_DRST_DRS_MASK)) {
      case 0x00U:
        MCGOUTClock *= 640U;
        break;
      case 0x20U:
        MCGOUTClock *= 1280U;
        break;
      case 0x40U:
        MCGOUTClock *= 1920U;
        break;
      case 0x60U:
        MCGOUTClock *= 2560U;
        break;
      case 0x80U:
        MCGOUTClock *= 732U;
        break;
      case 0xA0U:
        MCGOUTClock *= 1464U;
        break;
      case 0xC0U:
        MCGOUTClock *= 2197U;
        break;
      case 0xE0U:
        MCGOUTClock *= 2929U;
        break;
      default:
        break;
    }
  } else if ((MCG->C1 & MCG_C1_CLKS_MASK) == 0x40U) {
    /* Internal reference clock is selected */
    if ((MCG->C2 & MCG_C2_IRCS_MASK) == 0x00U) {
      MCGOUTClock = CPU_INT_SLOW_CLK_HZ; /* Slow internal reference clock selected */
    } else { /* (!((MCG->C2 & MCG_C2_IRCS_MASK) == 0x00U)) */
      Divider = (uint16_t)(0x01LU << ((MCG->SC & MCG_SC_FCRDIV_MASK) >> MCG_SC_FCRDIV_SHIFT));
      MCGOUTClock = (uint32_t) (CPU_INT_FAST_CLK_HZ / Divider); /* Fast internal reference clock selected */
    } /* (!((MCG->C2 & MCG_C2_IRCS_MASK) == 0x00U)) */
  } else if ((MCG->C1 & MCG_C1_CLKS_MASK) == 0x80U) {
    /* External reference clock is selected */
    if((MCG->C7 & MCG_C7_OSCSEL_MASK) == 0x00U) {
      MCGOUTClock = CPU_XTAL_CLK_HZ;   /* System oscillator drives MCG clock */
    } else {
      MCGOUTClock = CPU_XTAL32k_CLK_HZ; /* RTC 32 kHz oscillator drives MCG clock */
    }
  } else { /* (!((MCG->C1 & MCG_C1_CLKS_MASK) == 0x80U)) */
    /* Reserved value */
    return;
  } /* (!((MCG->C1 & MCG_C1_CLKS_MASK) == 0x80U)) */
  SystemCoreClock = (MCGOUTClock / (0x01U + ((SIM->CLKDIV1 & SIM_CLKDIV1_OUTDIV1_MASK) >> SIM_CLKDIV1_OUTDIV1_SHIFT)));

}