em_gpcrc.c

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/***************************************************************************/
#include "em_gpcrc.h"
#include "em_assert.h"

#if defined(GPCRC_PRESENT) && (GPCRC_COUNT > 0)

/***************************************************************************/
/***************************************************************************/
/*******************************************************************************
 ***************************   GLOBAL FUNCTIONS   ******************************
 ******************************************************************************/

/***************************************************************************/
void GPCRC_Init(GPCRC_TypeDef * gpcrc, const GPCRC_Init_TypeDef * init)
{
  uint32_t polySelect;

  if (init->crcPoly == 0x04C11DB7)
  {
    polySelect = GPCRC_CTRL_POLYSEL_CRC32;
  }
  else
  {
    // If not using the fixed CRC-32 polynomial then we must be using 16-bit
    EFM_ASSERT((init->crcPoly & 0xFFFF0000) == 0);
    polySelect = GPCRC_CTRL_POLYSEL_16;
  }

  gpcrc->CTRL = (((uint32_t)init->autoInit << _GPCRC_CTRL_AUTOINIT_SHIFT)
                | ((uint32_t)init->reverseByteOrder << _GPCRC_CTRL_BYTEREVERSE_SHIFT)
                | ((uint32_t)init->reverseBits << _GPCRC_CTRL_BITREVERSE_SHIFT)
                | ((uint32_t)init->enableByteMode << _GPCRC_CTRL_BYTEMODE_SHIFT)
                | polySelect
                | ((uint32_t)init->enable << _GPCRC_CTRL_EN_SHIFT));

  if (polySelect == GPCRC_CTRL_POLYSEL_16)
  {
    // Set CRC polynomial value
    uint32_t revPoly = __RBIT(init->crcPoly) >> 16;
    gpcrc->POLY = revPoly & _GPCRC_POLY_POLY_MASK;
  }

  // Load CRC initialization value to GPCRC_INIT
  gpcrc->INIT = init->initValue;
}

/***************************************************************************/
void GPCRC_Reset(GPCRC_TypeDef * gpcrc)
{
  gpcrc->CTRL = _GPCRC_CTRL_RESETVALUE;
  gpcrc->POLY = _GPCRC_POLY_RESETVALUE;
  gpcrc->INIT = _GPCRC_INIT_RESETVALUE;
}

#endif /* defined(GPCRC_COUNT) && (GPCRC_COUNT > 0) */