/*
** ###################################################################
**     Processors:          MK26FN2M0CAC18
**                          MK26FN2M0VLQ18
**                          MK26FN2M0VMD18
**                          MK26FN2M0VMI18
**
**     Compilers:           Keil ARM C/C++ Compiler
**                          Freescale C/C++ for Embedded ARM
**                          GNU C Compiler
**                          IAR ANSI C/C++ Compiler for ARM
**                          MCUXpresso Compiler
**
**     Reference manual:    MK26P169M180SF5RM, Rev. 1, Mar 2015
**     Version:             rev. 2.0, 2015-03-25
**     Build:               b180801
**
**     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 2016 Freescale Semiconductor, Inc.
**     Copyright 2016-2018 NXP
**
**     SPDX-License-Identifier: BSD-3-Clause
**
**     http:                 www.nxp.com
**     mail:                 support@nxp.com
**
**     Revisions:
**     - rev. 1.0 (2014-12-04)
**         Initial version.
**     - rev. 1.1 (2015-02-19)
**         Renamed interrupt vector LLW to LLWU.
**     - rev. 2.0 (2015-03-25)
**         Registers updated according to the reference manual revision 1, March 2015
**
** ###################################################################
*/

/*!
 * @file MK26F18
 * @version 2.0
 * @date 2015-03-25
 * @brief Device specific configuration file for MK26F18 (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 ((__FPU_PRESENT == 1) && (__FPU_USED == 1))
  SCB->CPACR |= ((3UL << 10*2) | (3UL << 11*2));    /* set CP10, CP11 Full Access */
#endif /* ((__FPU_PRESENT == 1) && (__FPU_USED == 1)) */
  /* Watchdog disable */
#if (DISABLE_WDOG)
  /* WDOG->UNLOCK: WDOGUNLOCK=0xC520 */
  WDOG->UNLOCK = WDOG_UNLOCK_WDOGUNLOCK(0xC520); /* Key 1 */
  /* WDOG->UNLOCK: WDOGUNLOCK=0xD928 */
  WDOG->UNLOCK = WDOG_UNLOCK_WDOGUNLOCK(0xD928); /* Key 2 */
  /* WDOG->STCTRLH: ?=0,DISTESTWDOG=0,BYTESEL=0,TESTSEL=0,TESTWDOG=0,?=0,?=1,WAITEN=1,STOPEN=1,DBGEN=0,ALLOWUPDATE=1,WINEN=0,IRQRSTEN=0,CLKSRC=1,WDOGEN=0 */
  WDOG->STCTRLH = WDOG_STCTRLH_BYTESEL(0x00) |
                 WDOG_STCTRLH_WAITEN_MASK |
                 WDOG_STCTRLH_STOPEN_MASK |
                 WDOG_STCTRLH_ALLOWUPDATE_MASK |
                 WDOG_STCTRLH_CLKSRC_MASK |
                 0x0100U;
#endif /* (DISABLE_WDOG) */

  SystemInitHook();
}

/* ----------------------------------------------------------------------------
   -- 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) {
    /* Output of FLL or PLL is selected */
    if ((MCG->C6 & MCG_C6_PLLS_MASK) == 0x00U) {
      /* FLL is selected */
      if ((MCG->C1 & MCG_C1_IREFS_MASK) == 0x00U) {
        /* External reference clock is selected */
        switch (MCG->C7 & MCG_C7_OSCSEL_MASK) {
        case 0x00U:
          MCGOUTClock = CPU_XTAL_CLK_HZ; /* System oscillator drives MCG clock */
          break;
        case 0x01U:
          MCGOUTClock = CPU_XTAL32k_CLK_HZ; /* RTC 32 kHz oscillator drives MCG clock */
          break;
        case 0x02U:
        default:
          MCGOUTClock = CPU_INT_IRC_CLK_HZ; /* IRC 48MHz oscillator drives MCG clock */
          break;
        }
        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 { /* (!((MCG->C6 & MCG_C6_PLLS_MASK) == 0x00U)) */
      if ((MCG->C11 & MCG_C11_PLLCS_MASK) == 0x00U) {
        /* PLL is selected */
        Divider = (((uint16_t)MCG->C5 & MCG_C5_PRDIV_MASK) + 0x01U);
        MCGOUTClock = (uint32_t)(CPU_XTAL_CLK_HZ / Divider); /* Calculate the PLL reference clock */
        Divider = (((uint16_t)MCG->C6 & MCG_C6_VDIV_MASK) + 16U);
        MCGOUTClock *= Divider;        /* Calculate the VCO output clock */
        MCGOUTClock /= 2;              /* Calculate the MCG output clock */
      } else {
        /* External PLL is selected */
        if ((USBPHY->ANACTRL & USBPHY_ANACTRL_PFD_CLK_SEL_MASK) == 0x00U) {
          MCGOUTClock = CPU_XTAL_CLK_HZ;
        } else {
          Divider = (((uint16_t)USBPHY->ANACTRL & USBPHY_ANACTRL_PFD_FRAC_MASK) >> 4);
          if ((USBPHY->ANACTRL & USBPHY_ANACTRL_PFD_CLK_SEL_MASK) == USBPHY_ANACTRL_PFD_CLK_SEL(1)) {
            Divider *= 0x04U;
          } else if ((USBPHY->ANACTRL & USBPHY_ANACTRL_PFD_CLK_SEL_MASK) == USBPHY_ANACTRL_PFD_CLK_SEL(2)) {
            Divider *= 0x02U;
          }
          MCGOUTClock = (uint32_t)(480000000 / Divider);
          MCGOUTClock *= 18;
        }
      }
    } /* (!((MCG->C6 & MCG_C6_PLLS_MASK) == 0x00U)) */
  } 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 */
    switch (MCG->C7 & MCG_C7_OSCSEL_MASK) {
    case 0x00U:
      MCGOUTClock = CPU_XTAL_CLK_HZ;   /* System oscillator drives MCG clock */
      break;
    case 0x01U:
      MCGOUTClock = CPU_XTAL32k_CLK_HZ; /* RTC 32 kHz oscillator drives MCG clock */
      break;
    case 0x02U:
    default:
      MCGOUTClock = CPU_INT_IRC_CLK_HZ; /* IRC 48MHz oscillator drives MCG clock */
      break;
    }
  } 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)));
}

/* ----------------------------------------------------------------------------
   -- SystemInitHook()
   ---------------------------------------------------------------------------- */

__attribute__ ((weak)) void SystemInitHook (void) {
  /* Void implementation of the weak function. */
}
