mmc_drv.c

This file contains the MMC driver routines

/*C**************************************************************************
* NAME:         mmc_drv.c
*----------------------------------------------------------------------------
* Copyright (c) 2003 Atmel.
*----------------------------------------------------------------------------
* RELEASE:      snd1c-refd-nf-4_0_3      
* REVISION:     1.5     
*----------------------------------------------------------------------------
* PURPOSE:
* This file contains the MMC driver routines
*
* NOTES:
* Driver Configuration:
*   - None
* Global Variables:
*   - None
*****************************************************************************/

/*_____ I N C L U D E S ____________________________________________________*/

#include "config.h"                         /* system configuration */
#include "mmc_drv.h"                        /* mmc driver definition */


/*_____ M A C R O S ________________________________________________________*/


/*_____ D E F I N I T I O N ________________________________________________*/

static  Byte    mmc_state;
static  bit     mmc_ready;                  /* MMC in prog state */


/*_____ D E C L A R A T I O N ______________________________________________*/

void    mmc_set_prio (Byte);
void    mmc_send_cmd (Byte, Uint32, Byte);
bit     mmc_check_response (void);


/*F**************************************************************************
* NAME: mmc_set_prio
*----------------------------------------------------------------------------
* PARAMS:
*
* return:
*----------------------------------------------------------------------------
* PURPOSE:
*   Set the MMC controller priority interrupt
*----------------------------------------------------------------------------
* EXAMPLE:
*----------------------------------------------------------------------------
* NOTE:
*----------------------------------------------------------------------------
* REQUIREMENTS: 
* ram/xram:
* cycle:
* stack: 
* code:
*****************************************************************************/
void mmc_set_prio (Byte priority)
{
  if ((priority == 1) || (priority == 3))     /* set LSB priority bit */
  {
    IPL1 |=  MSK_ESPI;
  }
  if ((priority == 2) || (priority == 3))     /* set MSB priority bit */
  {
    IPH1 |= MSK_ESPI;
  }
}


/*F**************************************************************************
* NAME: mmc_send_cmd
*----------------------------------------------------------------------------
* PARAMS:
*   index:    command index
*   argument: argument (32 bits) of the command to send
*   response: expected response to the command to send
*
* return:
*----------------------------------------------------------------------------
* PURPOSE:
*   Send a command on the bus
*----------------------------------------------------------------------------
* EXAMPLE:
*----------------------------------------------------------------------------
* NOTE:
*   The fifo lock flag is not tested it is under firmware responsability to
*   take care of inter-command delays 
*----------------------------------------------------------------------------
* REQUIREMENTS: 
* ram/xram:
* cycle:
* stack: 
* code:
*****************************************************************************/
void mmc_send_cmd (Byte index, Uint32 argument, Byte response)
{
  MMCMD = index;
  MMCMD = ((Byte*)&argument)[0];
  MMCMD = ((Byte*)&argument)[1];
  MMCMD = ((Byte*)&argument)[2];
  MMCMD = ((Byte*)&argument)[3];

  switch (response)
  {
    case MMC_RESP_R1:
    case MMC_RESP_R4:
    case MMC_RESP_R5:
    {
      MMCON0 |= MSK_RFMT;                   /* set 48 bits response */
      MMCON0 &= ~MSK_CRCDIS;                /* set response with CRC7 */
      MMCON1 |= (MSK_CMDEN|MSK_RESPEN);
      MMCON1 &= ~(MSK_CMDEN|MSK_RESPEN);    /* send command with response */
      break;
    }
    case MMC_RESP_R2:
    {
      MMCON0 &= ~(MSK_RFMT | MSK_CRCDIS);   /* set 136 bits response with CRC7 */
      MMCON1 |= (MSK_CMDEN|MSK_RESPEN);
      MMCON1 &= ~(MSK_CMDEN|MSK_RESPEN);    /* send command with response */
      break;
    }
    case MMC_RESP_R3:
    {
      MMCON0 |= (MSK_RFMT | MSK_CRCDIS);    /* set 48 bits response without CRC7 */
      MMCON1 |= (MSK_CMDEN|MSK_RESPEN);
      MMCON1 &= ~(MSK_CMDEN|MSK_RESPEN);    /* send command with response */
      break;
    }
    case MMC_NO_RESP:
    default:
    {
      MMCON1 |= MSK_CMDEN;
      MMCON1 &= ~MSK_CMDEN;                 /* send command without response */
      break;
    }
  }
}


/*F**************************************************************************
* NAME: mmc_send_scmd
*----------------------------------------------------------------------------
* PARAMS:
*   index:    command index
*   response: expected response to the command to send
*
* return:
*----------------------------------------------------------------------------
* PURPOSE:
*   Send a short command on the bus
*----------------------------------------------------------------------------
* EXAMPLE:
*----------------------------------------------------------------------------
* NOTE:
*   The fifo lock flag is not tested it is under firmware responsability to
*   take care of inter-command delays 
*----------------------------------------------------------------------------
* REQUIREMENTS: 
* ram/xram:
* cycle:
* stack: 
* code:
*****************************************************************************/
void mmc_send_scmd (Byte index, Byte response)
{
  MMCMD = index;
  MMCMD = (Byte)MMC_NO_ARG;
  MMCMD = (Byte)MMC_NO_ARG;
  MMCMD = (Byte)MMC_NO_ARG;
  MMCMD = (Byte)MMC_NO_ARG;

  switch (response)
  {
    case MMC_RESP_R1:
    case MMC_RESP_R4:
    case MMC_RESP_R5:
    case SD_RESP_R6:
    {
      MMCON0 |= MSK_RFMT;                   /* set 48 bits response */
      MMCON0 &= ~MSK_CRCDIS;                /* set response with CRC7 */
      MMCON1 |= (MSK_CMDEN|MSK_RESPEN);
      MMCON1 &= ~(MSK_CMDEN|MSK_RESPEN);    /* send command with response */
      break;
    }
    case MMC_RESP_R2:
    {
      MMCON0 &= ~(MSK_RFMT | MSK_CRCDIS);   /* set 136 bits response with CRC7 */
      MMCON1 |= (MSK_CMDEN|MSK_RESPEN);
      MMCON1 &= ~(MSK_CMDEN|MSK_RESPEN);    /* send command with response */
      break;
    }
    case MMC_RESP_R3:
    {
      MMCON0 |= (MSK_RFMT | MSK_CRCDIS);    /* set 48 bits response without CRC7 */
      MMCON1 |= (MSK_CMDEN|MSK_RESPEN);
      MMCON1 &= ~(MSK_CMDEN|MSK_RESPEN);    /* send command with response */
      break;
    }
    case MMC_NO_RESP:
    default:
    {
      MMCON1 |= MSK_CMDEN;
      MMCON1 &= ~MSK_CMDEN;                 /* send command without response */
      break;
    }
  }
}


/*F**************************************************************************
* NAME: mmc_check_response
*----------------------------------------------------------------------------
* PARAMS:
*
* return:
*   MMC_ERR_RESP: no response or bad format received
*   MMC_RESP_OK:  response received
*----------------------------------------------------------------------------
* PURPOSE: 
*   Check command response 
*----------------------------------------------------------------------------
* EXAMPLE:
*----------------------------------------------------------------------------
* NOTE:
*----------------------------------------------------------------------------
* REQUIREMENTS:
* ram/xram:
* cycle:
* stack: 
* code:
*****************************************************************************/
bit mmc_check_response (void)
{
  if (Mmc_response_received())
  { /* response received */
    if ((MMCON0 & MSK_CRCDIS) != 0)
    {                                         /* CRC7 not computed */
      if ((MMSTA & MSK_RESPFS) != 0)
      {
        return (MMC_RESP_OK);
      }
      else
      {
        return (MMC_ERR_RESP);                /* format error */
      }
    }
    else
    {                                         /* CRC7 computed */
      if ((MMSTA & (MSK_RESPFS | MSK_CRC7S)) == (MSK_RESPFS | MSK_CRC7S))
      {
        return (MMC_RESP_OK);
      }
      else
      {
        return (MMC_ERR_RESP);                /* format or CRC7 error */
      }
    }
  }
  else
  { /* no response received */
    return (MMC_ERR_RESP);
  }
}


/*F**************************************************************************
* NAME: mmc_read_response
*----------------------------------------------------------------------------
* PARAMS:
*
* return:
*   4-byte argument of the response
*----------------------------------------------------------------------------
* PURPOSE: 
*   Read command argument response 
*----------------------------------------------------------------------------
* EXAMPLE:
*----------------------------------------------------------------------------
* NOTE:
*----------------------------------------------------------------------------
* REQUIREMENTS:
* ram/xram:
* cycle:
* stack: 
* code:
*****************************************************************************/
Uint32 mmc_read_response (void)
{
Uint32  argument;

  ((Byte*)&argument)[0] = MMCMD;    /* dummy index read */
  ((Byte*)&argument)[0] = MMCMD;
  ((Byte*)&argument)[1] = MMCMD;
  ((Byte*)&argument)[2] = MMCMD;
  ((Byte*)&argument)[3] = MMCMD;

  return argument;
}