cf卡.txt

cf卡读写成功的例子

      printf("error reg: 0x%X\r", IORD_ALTERA_AVALON_CF_IDE_ERROR(ide_base));
      return -1;
    }
    
    /* PIO read step (h) */
    usStatus = IORD_ALTERA_AVALON_CF_IDE_STATUS(ide_base);
    usStatus = IORD_ALTERA_AVALON_CF_IDE_ALTERNATE_STATUS(ide_base);

    /* PIO read step (i) */
    if (usStatus & AltStatusRegBitDRQ)
    {
        for (i = 0; i < 256; ++i)
        {
          iIndex = i + 256 * iSect;
          // printf("writing byte at index %d\r", iIndex);
          pusBuffer[iIndex] = IORD_ALTERA_AVALON_CF_IDE_DATA(ide_base);
        }
    }
    else
    {
      printf("readSectorsGuts(): error: DRQ not set in status reg\n");
      return -1;
    }
  }

  return 0;
}
//++++++++++++++++++读扇区 LBA模式！！！！关键++++++++++++++++++++++++++++//
/*
 * readSectorsLBA()
 * 
 * Read sector(s) in LBA mode addressing.
 */
int readSectorsLBA(int iDevice, unsigned long ulLBA,
    int iSectorCount, unsigned short *pusBuffer)
{
  if (gbVerbose)   
  {
    printf("LBA = %u; numSectors: %d\r", (unsigned int)ulLBA, iSectorCount);
  }

  /* PIO read steps (a) through (c) */
  if (PIODataInOrOutPreamble(iDevice))
  {
    printf("readSectorsLBA(): PIODataInOrOutPreamble failed.\r");
    return -1;
  }

  /* PIO read step (d) */
  IOWR_ALTERA_AVALON_CF_IDE_SECTOR_COUNT(ide_base,  iSectorCount); //写入扇区计数寄存器
  IOWR_ALTERA_AVALON_CF_IDE_SECTOR_NUMBER(ide_base, ulLBA & 0xFF);  //扇区寄存器
  ulLBA >>= 8;
  IOWR_ALTERA_AVALON_CF_IDE_CYLINDER_LOW(ide_base,  ulLBA & 0xFF);  //柱面低位寄存器
  ulLBA >>= 8;
  IOWR_ALTERA_AVALON_CF_IDE_CYLINDER_HIGH(ide_base, ulLBA & 0xFF);  //柱面高位寄存器
  ulLBA >>= 8;
  IOWR_ALTERA_AVALON_CF_IDE_DEVICE_HEAD(ide_base, 
    (ulLBA & 0x0F) | 0xE0 |  // LBA on
    (iDevice ? DevHeadRegBitDEV : 0));   //设置磁头寄存器（高3位、设定lba模式，设备号） 

  /* PIO read step (e) */
  IDEinterrupt = 0;    
  IOWR_ALTERA_AVALON_CF_IDE_COMMAND(ide_base, ReadSectorWithRetries);   //写入命令寄存器命令字

  /* PIO read steps (f-j) */
  return readSectorsGuts(iSectorCount, pusBuffer);  //返回读扇区！？函数在上面看星号处
}

/* 
 * Brief primer on PIO mode IDE writes. The comments below are referenced
 * in relevant code in the low-level write routines:
 *
 * PIO Data Out:
 * a) The host reads the status or alt status reg until BSY=0.
 * b) The host writes the dev/head register with the appropriate dev
 *    bit value.
 * c) The host reads the status or alt status register until BSY=0 and
 *    DRDY=1.
 * d) The host writes any required command parameters to the Features,
 *    Sector Count, Sector Number, Cylinder High, Cylinder Low and
 *    Device/Head registers.
 * e) The host writes the command code to the Command register.
 * f) The device sets the BSY bit and prepares to execute the command
 *    including preparation to transfer the first block of data to the
 *    host.  (Note: it may take up to 400ns for BSY to go high.)
 * g) When ready to receive the first block of data from the host, the device
 *    sets the DRQ bit (setting the DRQ bit is optional if an error condition
 *    exists) and any other status or error bits as required and clears the BSY
 *    bit.
 * h) The host reads the status or alternate status register until BSY is
 *    equal to 0.
 * i) If the DRQ bit is set, the host transfers a complete block of data to
 *    the device by writing the Data register.
 * j) Next, one of the following actions is taken:
 *    - if an error status was present in the status read in step h), the device
 *      clears the DRQ bit, asserts INTRQ and the command execution is complete.
 *      The data transferred in steup i) is not processed by the device.
 *    - if no error status was presented to the host in step h), the device sets
 *      the BSY bit and processing continues with the next step.
 * k) The device processes the data block just received from the host.  When
 *    this processing is completed, one of the following actions is taken:
 *    - If no error occurred while processing the data block and if no add'l
 *      blocks are to be transferred, the device clears the BSY bit and then
 *      asserts INTRQ.  Command execution is complete;
 *    - If an error occured while processing the data block the device sets the
 *      appropriate bits as required by the error condition.  The device clears
 *      the BSY bit and then asserts INTRQ.  Command execution is complete.
 *    - If no error occurred while processing the data block and if the transfer
 *      of another block is required, processing continues with the next step.
 * l) When ready to receive the next block from the host, the device sets the
 *    DRQ bit, clears the BSY bit and then asserts INTRQ;
 * m) After detecting either BSY=0 (alternate status) or INTRQ, the host reads
 *    the contents of the status register.
 * n) The host transfers a complete block of data to the device by writing
 *    the data register.
 * o) The device sets the BSY bit and processing continues at step k).
 */

/*
 * writeSectorsGuts()
 * 
 * Low-level write comands common to both CHS & LBA PIO-mode IDE writes
 */


int writeSectorsGuts(int iSectorCount, unsigned short *pusBuffer)
{
  int i, iNumSectorsWritten = 0;
  unsigned short usStatus;
   
  /* PIO write step (e) */
  IOWR_ALTERA_AVALON_CF_IDE_COMMAND(ide_base, WriteSectorWithRetries);

  /* PIO write step (f) */
  usleep(1);

  /* PIO write steps (g) & (h) */
  if (awaitBSYZero(1000))
  {
    printf("writeSectorsGuts(): error: timeout (2) awaiting BSY=0\n");
    return -1;
  }
  usStatus = IORD_ALTERA_AVALON_CF_IDE_STATUS(ide_base);

  /* PIO write step (i) */
  usStatus = IORD_ALTERA_AVALON_CF_IDE_ALTERNATE_STATUS(ide_base);
  if (usStatus & StatusRegBitDRQ)
  {
    for (i = 0; i < 256; ++i)
    {
      IOWR_ALTERA_AVALON_CF_IDE_DATA(ide_base, pusBuffer[i]);
    }
  }
  else
  {
    printf("writeSectorsGuts(): error: DRQ not set.\r");
    return -1;
  }

  /* PIO write step (j) */
  if (usStatus & AltStatusRegBitERR)
  {
    printf("writeSectorsGuts(): error occurred during write (error reg=0x%X)\n",
      IORD_ALTERA_AVALON_CF_IDE_ERROR(ide_base));
    awaitINTRQ(1000);
    return -1;
  }

  iNumSectorsWritten++;

  while (1)
  {
    /* PIO write step (k) */
    if (awaitBSYZero(1000))
    {
      printf("writeSectorsGuts(): error: timeout (3) awaiting BSY=0\n");
      return -1;
    }
    
    if (awaitINTRQ(5000))
    {
      printf("writeSectorsGuts(): error: timeout awaiting INTRQ=1\n");
      printf("error reg: 0x%X\r", IORD_ALTERA_AVALON_CF_IDE_ERROR(ide_base));
      return -1;
    }
    
    usStatus = IORD_ALTERA_AVALON_CF_IDE_STATUS(ide_base);
    if (usStatus & StatusRegBitERR)
    {
      printf("writeSectorsGuts(): error occured (error reg=0x%X\n",
        IORD_ALTERA_AVALON_CF_IDE_ERROR(ide_base));
      return -1;
    }

    if (iNumSectorsWritten >= iSectorCount)
    {
      return 0;
    }

    /* PIO write step (l) */
    if (awaitDRQ(1000))
    {
      printf("writeSectorsGuts(): timeout awaiting DRQ for multi-sector write.\n");
      return -1;
    }

    /* PIO write step (m) */
    if (awaitBSYZeroOrINTRQ(1000))
    {
      printf("writeSectorsGuts(): timeout awaiting BSY=0 or INTRQ\n");
      return -1;
    }

    usStatus = IORD_ALTERA_AVALON_CF_IDE_STATUS(ide_base);

    /* PIO write step (n) */
    for (i = 0; i < 256; ++i)
    {
      IOWR_ALTERA_AVALON_CF_IDE_DATA(ide_base, 
        pusBuffer[i + iNumSectorsWritten * 256]);
    }
    
    /* PIO write step (o) */
    iNumSectorsWritten++;
  }
  
  return 0;
} 

///***********************写扇区lba方式********************************/////
 
/*
 * writeSectorsLBA()
 * 
 * Write sector(s) in LBA mode addressing.
 */
int writeSectorsLBA(int iDevice, unsigned long ulLBA,
    int iSectorCount, unsigned short *pusBuffer)
{
  if (gbVerbose)
  {
    printf("LBA = %u; numSectors: %d\r", (unsigned int)ulLBA, iSectorCount);
  }

  /* PIO write steps (a) through (c) */
  if (PIODataInOrOutPreamble(iDevice))
  {
    printf("writeSectorsLBA(): PIODataInOrOutPreamble failed.\r");
    return -1;
  }

  /* PIO write step (d) */
  IOWR_ALTERA_AVALON_CF_IDE_SECTOR_COUNT(ide_base,  iSectorCount);
  IOWR_ALTERA_AVALON_CF_IDE_SECTOR_NUMBER(ide_base, ulLBA & 0xFF);
  ulLBA >>= 8;
  IOWR_ALTERA_AVALON_CF_IDE_CYLINDER_LOW(ide_base,  ulLBA & 0xFF);
  ulLBA >>= 8;
  IOWR_ALTERA_AVALON_CF_IDE_CYLINDER_HIGH(ide_base, ulLBA & 0xFF);
  ulLBA >>= 8;
  IOWR_ALTERA_AVALON_CF_IDE_DEVICE_HEAD(ide_base,  
    (ulLBA & 0x0F) | 0xE0 |  // LBA on
    (iDevice ? DevHeadRegBitDEV : 0));

  /* PIO write steps (e) through (o) */
  if(writeSectorsGuts(iSectorCount, pusBuffer))
  {
    printf("writeSectorsCHS(): writeSectorsGuts failed.\n");
    return -1;    
  }

  return 0;
}



/*
 * IDE_initializeDeviceParameters()                               //ide设备参数初始化
 * 
 * For some reason IDE devices need their parameters written into them after
 * initialization where these same parameters were earlier read out. Bizarre.
 */


int IDE_initializeDeviceParameters(int iDevice,
  unsigned short usLogicalHeads, unsigned short usLogicalCylinders,
  unsigned short usSectorsPerTrack)
{
  unsigned short usStatus, usError;

  /* PIO read/write steps (a) through (c) */
  if (PIODataInOrOutPreamble(iDevice))
  {
    printf("IDE_initializeDeviceParameters(): PIODataInOrOutPreamble failed.\r");
    return -1;
  }

  IOWR_ALTERA_AVALON_CF_IDE_SECTOR_COUNT(ide_base, usSectorsPerTrack);
  IOWR_ALTERA_AVALON_CF_IDE_DEVICE_HEAD(ide_base,
    (iDevice ? DevHeadRegBitDEV : 0) | (usLogicalHeads - 1));
  IDEinterrupt = 0;                                               //ide中断标志付
  IOWR_ALTERA_AVALON_CF_IDE_COMMAND(ide_base, InitializeDeviceParameters);

  /* Wait for INTRQ. */
  if (awaitINTRQ(5000))
  {
    printf("timeout awaiting INTRQ=1 in initializeDeviceParameters()\r");
    printf("error register: 0x%X\r", IORD_ALTERA_AVALON_CF_IDE_ERROR(ide_base));
    printf("status register: 0x%X\r", IORD_ALTERA_AVALON_CF_IDE_STATUS(ide_base));
    return -1;
  }

  usStatus = IORD_ALTERA_AVALON_CF_IDE_STATUS(ide_base);
  if (usStatus & StatusRegBitERR)
  {
    usError = IORD_ALTERA_AVALON_CF_IDE_ERROR(ide_base);
    printf("Error? status: 0x%X; error: 0x%X\r", usStatus, usError);
  }
  else
  {
    if (IDE_getVerbosity())
    {
      printf("successfully wrote default parameters to IDE drive.\n");     //顺利写入默认参数到ide设备
    }
  }

  return 0;
}

//===-=-=-=-=-=-=-=-=-=-=--=-=-=-=-=-=--=-=-=-=-解析识别设备缓存=-=-=-=-=-=-=-=-=-=-=-=-=-=-==-=-=--=-=-=-=-==-=-===-==-=-=-=-=-=-=-=-//
/*
 * parseIdentifyDeviceBuffer()//解析识别设备缓存
 * 
 * Parse read IDE device parameters & store them in relevant variables. Also
 * displays a handy print-out of information about the attached device, in
 * verbose mode.解析读ide设备参数或者存储他们在相应的变量中，同时，显示一个附上设备的易得的信息，用详细的方式
 */
void parseIdentifyDeviceBuffer(unsigned short *pusBuffer)
{
  int i;
  char *p;
  
  p = gModel;
  
  for (i = 27; i <= 46; ++i) 
  {
    *p++ = (char) (pusBuffer[i] >> 8);
    *p++ = (char) (pusBuffer[i] & 0xFF);
  }

  if (gbVerbose)           //@@@#!#!#!#!#!#@#$!@#$@#$@#$@#$@#$@#$@#$@#$     冗余参数
  {
#if IDE_DEBUG
    printf("buffer: \n");
    for (i = 0; i < 256; ++i)
    {
      printf("%d: 0x%x\n", i, pusBuffer[i]);
    }
#endif

    printf("serial number: ");  //序列号
    for (i = 10; i < 20; ++i)
    {
      printf("%c%c", pusBuffer[i] >> 8, pusBuffer[i] & 0xFF);
    }
    printf("\n");

    printf("firmware revision: ");//固件修订本
    for (i = 23; i < 27; ++i)
    {
      printf("%c%c", pusBuffer[i] >> 8, pusBuffer[i] & 0xFF);
    }
    printf("\n");

    printf("model number: %s\n", gModel);  //模式
  }

  if(((0x2<<8) & pusBuffer[49] ) != 0)      //lba模式支持   49字：功能 第九位被设置为1，说明支持lba模式
  {
    gusLBAmode = 1;
    gulLBAcapacity = pusBuffer[60] + (pusBuffer[61]<<16);  //磁盘的容量
  }

  if((0x2 & pusBuffer[64] ) != 0)     //
  {
    gusPIOmode = 4;
  }
  else if ((0x01 & pusBuffer[64] ) != 0)          //高级pio模式支持
  {
    gusPIOmode = 3;                  
  }
  else
  {
    gusPIOmode = pusBuffer[51] >> 8;
  }

  if (gusPIOmode > 4)
  {
    gusPIOmode = 0;
  }

  gusLogicalCylinders = pusBuffer[1];    //获得设备真正的柱面
  gusLogicalHeads = pusBuffer[3];        //磁头数
  gusSectorsPerTrack = pusBuffer[6];     //扇区数
  
  if (gbVerbose)
  {
    printf("LBA mode %ssupported\n", gusLBAmode ? "" : "not ");
    printf("PIO mode supported: %d\n", gusPIOmode);
    printf("device parameters:\n");
    printf(
      "  # logical cylinders: %d\n"
      "  # logical heads: %d\n"
      "  # logical sectors/track: %d\n",
      gusLogicalCylinders, gusLogicalHeads, gusSectorsPerTrack);
    if(gusLBAmode)
    {
      printf("  LBA capacity = %u sectors\n",  (unsigned int)gulLBAcapacity);
    }
  }
}



//=======================IDE_identifyDevice() ==============================================================================================//
/*
 * IDE_identifyDevice() 
 * 
 * Attempt to identify parameters for the specified IDE device.//尝试识别特定的ide设备参数
 */
int IDE_identifyDevice(unsigned int uiDeviceNumber)
{
  int i;
  unsigned short usStatus, usBuffer[256];//