stm32f7xx_hal_crc.c

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/* Includes ------------------------------------------------------------------*/
#include "stm32f7xx_hal.h"

#ifdef HAL_CRC_MODULE_ENABLED

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
static uint32_t CRC_Handle_8(CRC_HandleTypeDef *hcrc, uint8_t pBuffer[], uint32_t BufferLength);
static uint32_t CRC_Handle_16(CRC_HandleTypeDef *hcrc, uint16_t pBuffer[], uint32_t BufferLength);
/* Exported functions --------------------------------------------------------*/

HAL_StatusTypeDef HAL_CRC_Init(CRC_HandleTypeDef *hcrc)
{
  /* Check the CRC handle allocation */
  if(hcrc == NULL)
  {
    return HAL_ERROR;
  }

  /* Check the parameters */
  assert_param(IS_CRC_ALL_INSTANCE(hcrc->Instance));

  if(hcrc->State == HAL_CRC_STATE_RESET)
  {
    /* Allocate lock resource and initialize it */
    hcrc->Lock = HAL_UNLOCKED;
    /* Init the low level hardware */
    HAL_CRC_MspInit(hcrc);
  }
  
  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_BUSY;
  
  /* check whether or not non-default generating polynomial has been 
   * picked up by user */
  assert_param(IS_DEFAULT_POLYNOMIAL(hcrc->Init.DefaultPolynomialUse)); 
  if(hcrc->Init.DefaultPolynomialUse == DEFAULT_POLYNOMIAL_ENABLE)
  {
    /* initialize IP with default generating polynomial */
    WRITE_REG(hcrc->Instance->POL, DEFAULT_CRC32_POLY);  
    MODIFY_REG(hcrc->Instance->CR, CRC_CR_POLYSIZE, CRC_POLYLENGTH_32B);
  }
  else
  {
    /* initialize CRC IP with generating polynomial defined by user */
    if(HAL_CRCEx_Polynomial_Set(hcrc, hcrc->Init.GeneratingPolynomial, hcrc->Init.CRCLength) != HAL_OK)
    {
      return HAL_ERROR;
    }
  }
  
  /* check whether or not non-default CRC initial value has been 
   * picked up by user */
  assert_param(IS_DEFAULT_INIT_VALUE(hcrc->Init.DefaultInitValueUse));
  if(hcrc->Init.DefaultInitValueUse == DEFAULT_INIT_VALUE_ENABLE)
  {
    WRITE_REG(hcrc->Instance->INIT, DEFAULT_CRC_INITVALUE);  
  }
  else
  {
    WRITE_REG(hcrc->Instance->INIT, hcrc->Init.InitValue);
  }
  

  /* set input data inversion mode */
  assert_param(IS_CRC_INPUTDATA_INVERSION_MODE(hcrc->Init.InputDataInversionMode)); 
  MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_IN, hcrc->Init.InputDataInversionMode); 
  
  /* set output data inversion mode */
  assert_param(IS_CRC_OUTPUTDATA_INVERSION_MODE(hcrc->Init.OutputDataInversionMode)); 
  MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_OUT, hcrc->Init.OutputDataInversionMode);  
  
  /* makes sure the input data format (bytes, halfwords or words stream)
   * is properly specified by user */
  assert_param(IS_CRC_INPUTDATA_FORMAT(hcrc->InputDataFormat));

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_READY;
  
  /* Return function status */
  return HAL_OK;
}

HAL_StatusTypeDef HAL_CRC_DeInit(CRC_HandleTypeDef *hcrc)
{
  /* Check the CRC handle allocation */
  if(hcrc == NULL)
  {
    return HAL_ERROR;
  }

  /* Check the parameters */
  assert_param(IS_CRC_ALL_INSTANCE(hcrc->Instance));
  
  /* Check the CRC peripheral state */
  if(hcrc->State == HAL_CRC_STATE_BUSY)
  {
    return HAL_BUSY;
  }
  
  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_BUSY;
  
  /* Reset CRC calculation unit */
  __HAL_CRC_DR_RESET(hcrc);

  /* DeInit the low level hardware */
  HAL_CRC_MspDeInit(hcrc);

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_RESET;

  /* Process unlocked */
  __HAL_UNLOCK(hcrc);

  /* Return function status */
  return HAL_OK;
}

__weak void HAL_CRC_MspInit(CRC_HandleTypeDef *hcrc)
{
  /* Prevent unused argument(s) compilation warning */
  UNUSED(hcrc);
  
  /* NOTE : This function should not be modified, when the callback is needed,
            the HAL_CRC_MspInit can be implemented in the user file
   */
}

__weak void HAL_CRC_MspDeInit(CRC_HandleTypeDef *hcrc)
{
  /* Prevent unused argument(s) compilation warning */
  UNUSED(hcrc);
  
  /* NOTE : This function should not be modified, when the callback is needed,
            the HAL_CRC_MspDeInit can be implemented in the user file
   */
}

uint32_t HAL_CRC_Accumulate(CRC_HandleTypeDef *hcrc, uint32_t pBuffer[], uint32_t BufferLength)
{
  uint32_t index = 0; /* CRC input data buffer index */
  uint32_t temp = 0;  /* CRC output (read from hcrc->Instance->DR register) */
  
  /* Process locked */
  __HAL_LOCK(hcrc); 
    
  /* Change CRC peripheral state */  
  hcrc->State = HAL_CRC_STATE_BUSY;
  
  switch (hcrc->InputDataFormat)
  {
    case CRC_INPUTDATA_FORMAT_WORDS:  
      /* Enter Data to the CRC calculator */
      for(index = 0; index < BufferLength; index++)
      {
        hcrc->Instance->DR = pBuffer[index];
      }
      temp = hcrc->Instance->DR;
      break;
      
    case CRC_INPUTDATA_FORMAT_BYTES: 
      temp = CRC_Handle_8(hcrc, (uint8_t*)pBuffer, BufferLength);
      break;
      
    case CRC_INPUTDATA_FORMAT_HALFWORDS: 
      temp = CRC_Handle_16(hcrc, (uint16_t*)pBuffer, BufferLength);
      break;
    default:
      break;  
  }
  
  /* Change CRC peripheral state */    
  hcrc->State = HAL_CRC_STATE_READY; 
  
  /* Process unlocked */
  __HAL_UNLOCK(hcrc);
  
  /* Return the CRC computed value */ 
  return temp;
}

uint32_t HAL_CRC_Calculate(CRC_HandleTypeDef *hcrc, uint32_t pBuffer[], uint32_t BufferLength)
{
  uint32_t index = 0; /* CRC input data buffer index */
  uint32_t temp = 0;  /* CRC output (read from hcrc->Instance->DR register) */
    
  /* Process locked */
  __HAL_LOCK(hcrc); 
  
  /* Change CRC peripheral state */  
  hcrc->State = HAL_CRC_STATE_BUSY;
  
  /* Reset CRC Calculation Unit (hcrc->Instance->INIT is 
  *  written in hcrc->Instance->DR) */
  __HAL_CRC_DR_RESET(hcrc);
  
  switch (hcrc->InputDataFormat)
  {
    case CRC_INPUTDATA_FORMAT_WORDS:  
      /* Enter 32-bit input data to the CRC calculator */
      for(index = 0; index < BufferLength; index++)
      {
        hcrc->Instance->DR = pBuffer[index];
      }
      temp = hcrc->Instance->DR;
      break;
      
    case CRC_INPUTDATA_FORMAT_BYTES: 
      /* Specific 8-bit input data handling  */
      temp = CRC_Handle_8(hcrc, (uint8_t*)pBuffer, BufferLength);
      break;
      
    case CRC_INPUTDATA_FORMAT_HALFWORDS: 
      /* Specific 16-bit input data handling  */
      temp = CRC_Handle_16(hcrc, (uint16_t*)pBuffer, BufferLength);
      break;
    default:
      break;
  }

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_READY;

  /* Process unlocked */
  __HAL_UNLOCK(hcrc);
  
  /* Return the CRC computed value */ 
  return temp;
}

static uint32_t CRC_Handle_8(CRC_HandleTypeDef *hcrc, uint8_t pBuffer[], uint32_t BufferLength)
{
  uint32_t i = 0; /* input data buffer index */
  
   /* Processing time optimization: 4 bytes are entered in a row with a single word write,
    * last bytes must be carefully fed to the CRC calculator to ensure a correct type
    * handling by the IP */
   for(i = 0; i < (BufferLength/4); i++)
   {
     hcrc->Instance->DR = (uint32_t)(((uint32_t)(pBuffer[4*i])<<24) | ((uint32_t)(pBuffer[4*i+1])<<16) | ((uint32_t)(pBuffer[4*i+2])<<8) | (uint32_t)(pBuffer[4*i+3]));
   }
   /* last bytes specific handling */
   if((BufferLength%4) != 0)
   {
     if(BufferLength%4 == 1)
     {
       *(__IO uint8_t*) (&hcrc->Instance->DR) = pBuffer[4*i];
     }
     if(BufferLength%4 == 2)
     {
       *(__IO uint16_t*)(&hcrc->Instance->DR) = (uint16_t)((uint16_t)((uint16_t)(pBuffer[4*i])<<8) | (uint16_t)(pBuffer[4*i+1]));
     }
     if(BufferLength%4 == 3)
     {
       *(__IO uint16_t*)(&hcrc->Instance->DR) = (uint16_t)((uint16_t)((uint16_t)(pBuffer[4*i])<<8) | (uint16_t)(pBuffer[4*i+1]));
       *(__IO uint8_t*) (&hcrc->Instance->DR) = pBuffer[4*i+2];       
     }
   }
  
  /* Return the CRC computed value */ 
  return hcrc->Instance->DR;
}

static uint32_t CRC_Handle_16(CRC_HandleTypeDef *hcrc, uint16_t pBuffer[], uint32_t BufferLength)
{
  uint32_t i = 0;  /* input data buffer index */
  
  /* Processing time optimization: 2 HalfWords are entered in a row with a single word write,
   * in case of odd length, last HalfWord must be carefully fed to the CRC calculator to ensure 
   * a correct type handling by the IP */
  for(i = 0; i < (BufferLength/2); i++)
  {
    hcrc->Instance->DR = (((uint32_t)(pBuffer[2*i])<<16) | (uint32_t)(pBuffer[2*i+1]));
  }
  if((BufferLength%2) != 0)
  {
     *(__IO uint16_t*) (&hcrc->Instance->DR) = (uint16_t)pBuffer[2*i];
  }
   
  /* Return the CRC computed value */ 
  return hcrc->Instance->DR;
}

HAL_CRC_StateTypeDef HAL_CRC_GetState(CRC_HandleTypeDef *hcrc)
{
  return hcrc->State;
}

#endif /* HAL_CRC_MODULE_ENABLED */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/