mindrvr.c

ata和atapi的驱动程序

// exec_non_data_cmd() - Execute a non-data command.
//
// This includes the strange ATAPI DEVICE RESET 'command'
// (command code 08H).
//
// Note special handling for Execute Device Diagnostics
// command when there is no device 0.
//
// See ATA-2 Section 9.5, ATA-3 Section 9.5,
// ATA-4 Section 8.8 Figure 12.  Also see Section 8.5.
//
//*************************************************************

static int exec_non_data_cmd( unsigned char dev );

static int exec_non_data_cmd( unsigned char dev )

{
   unsigned char secCnt;
   unsigned char secNum;
   unsigned char status;
   int polled = 0;

   // reset Bus Master Error bit

   pio_writeBusMstrStatus( BM_SR_MASK_ERR );

   // Set command time out.

   tmr_set_timeout();

   // PAY ATTENTION HERE
   // If the caller is attempting a Device Reset command, then
   // don't do most of the normal stuff.  Device Reset has no
   // parameters, should not generate an interrupt and it is the
   // only command that can be written to the Command register
   // when a device has BSY=1 (a very strange command!).  Not
   // all devices support this command (even some ATAPI devices
   // don't support the command.

   if ( reg_cmd_info.cmd != CMD_DEVICE_RESET )
   {
      // Select the drive - call the sub_select function.
      // Quit now if this fails.

      if ( sub_select( dev ) )
      {
         return 1;
      }

      // Set up all the registers except the command register.

      sub_setup_command();
   }

   // Start the command by setting the Command register.  The drive
   // should immediately set BUSY status.

   pio_outbyte( CB_CMD, reg_cmd_info.cmd );

   // Waste some time by reading the alternate status a few times.
   // This gives the drive time to set BUSY in the status register on
   // really fast systems.  If we don't do this, a slow drive on a fast
   // system may not set BUSY fast enough and we would think it had
   // completed the command when it really had not even started the
   // command yet.

   DELAY400NS;

   // IF
   //    This is an Exec Dev Diag command (cmd=0x90)
   //    and there is no device 0 then
   //    there will be no interrupt. So we must
   //    poll device 1 until it allows register
   //    access and then do normal polling of the Status
   //    register for BSY=0.
   // ELSE
   // IF
   //    This is a Dev Reset command (cmd=0x08) then
   //    there should be no interrupt.  So we must
   //    poll for BSY=0.
   // ELSE
   //    Do the normal wait for interrupt or polling for
   //    completion.

   if ( ( reg_cmd_info.cmd == CMD_EXECUTE_DEVICE_DIAGNOSTIC )
        &&
        ( reg_config_info[0] == REG_CONFIG_TYPE_NONE )
      )
   {
      polled = 1;
      while ( 1 )
      {
         pio_outbyte( CB_DH, CB_DH_DEV1 );
         DELAY400NS;
         secCnt = pio_inbyte( CB_SC );
         secNum = pio_inbyte( CB_SN );
         if ( ( secCnt == 0x01 ) && ( secNum == 0x01 ) )
            break;
         if ( tmr_chk_timeout() )
         {
            reg_cmd_info.to = 1;
            reg_cmd_info.ec = 24;
            break;
         }
      }
   }
   else
   {
      if ( reg_cmd_info.cmd == CMD_DEVICE_RESET )
      {
         // Wait for not BUSY -or- wait for time out.

         polled = 1;
         sub_wait_poll( 0, 23 );
      }
      else
      {
         // Wait for interrupt -or- wait for not BUSY -or- wait for time out.

         if ( ! int_use_intr_flag )
            polled = 1;
         sub_wait_poll( 22, 23 );
      }
   }

   // If status was polled or if any error read the status register,
   // otherwise get the status that was read by the interrupt handler.

   if ( ( polled ) || ( reg_cmd_info.ec ) )
      status = pio_inbyte( CB_STAT );
   else
      status = int_ata_status;

   // Error if BUSY, DEVICE FAULT, DRQ or ERROR status now.

   if ( reg_cmd_info.ec == 0 )
   {
      if ( status & ( CB_STAT_BSY | CB_STAT_DF | CB_STAT_DRQ | CB_STAT_ERR ) )
      {
         reg_cmd_info.ec = 21;
      }
   }

   // BMIDE Error=1?

   if ( pio_readBusMstrStatus() & BM_SR_MASK_ERR )
   {
      reg_cmd_info.ec = 78;                  // yes
   }

   // NON_DATA_DONE:

   // All done.  The return values of this function are described in
   // MINDRVR.H.

   sub_trace_command();
   if ( reg_cmd_info.ec )
      return 1;
   return 0;
}

//*************************************************************
//
// reg_non_data_lba28() - Easy way to execute a non-data command
//                        using an LBA sector address.
//
//*************************************************************

int reg_non_data_lba28( unsigned char dev, unsigned char cmd,
                        unsigned int fr, unsigned int sc,
                        unsigned long lba )

{

   // Setup current command information.

   reg_cmd_info.cmd = cmd;
   reg_cmd_info.fr = fr;
   reg_cmd_info.sc = sc;
   reg_cmd_info.dh = (unsigned char) ( CB_DH_LBA | ( dev ? CB_DH_DEV1 : CB_DH_DEV0 ) );
   reg_cmd_info.dc = (unsigned char) ( int_use_intr_flag ? 0 : CB_DC_NIEN );
   reg_cmd_info.ns  = sc;
   reg_cmd_info.lbaSize = LBA28;
   reg_cmd_info.lbaHigh = 0L;
   reg_cmd_info.lbaLow = lba;

   // Execute the command.

   return exec_non_data_cmd( dev );
}

//*************************************************************
//
// reg_non_data_lba48() - Easy way to execute a non-data command
//                        using an LBA sector address.
//
//*************************************************************

int reg_non_data_lba48( unsigned char dev, unsigned char cmd,
                        unsigned int fr, unsigned int sc,
                        unsigned long lbahi, unsigned long lbalo )

{

   // Setup current command infomation.

   reg_cmd_info.cmd = cmd;
   reg_cmd_info.fr = fr;
   reg_cmd_info.sc = sc;
   reg_cmd_info.dh = (unsigned char) ( CB_DH_LBA | ( dev ? CB_DH_DEV1 : CB_DH_DEV0 ) );
   reg_cmd_info.dc = (unsigned char) ( int_use_intr_flag ? 0 : CB_DC_NIEN );
   reg_cmd_info.ns  = sc;
   reg_cmd_info.lbaSize = LBA48;
   reg_cmd_info.lbaHigh = lbahi;
   reg_cmd_info.lbaLow = lbalo;

   // Execute the command.

   return exec_non_data_cmd( dev );
}

//*************************************************************
//
// exec_pio_data_in_cmd() - Execute a PIO Data In command.
//
// See ATA-2 Section 9.3, ATA-3 Section 9.3,
// ATA-4 Section 8.6 Figure 10.
//
//*************************************************************

static int exec_pio_data_in_cmd( unsigned char dev,
                            unsigned char * bufAddr,
                            long numSect, int multiCnt );


static int exec_pio_data_in_cmd( unsigned char dev,
                            unsigned char * bufAddr,
                            long numSect, int multiCnt )

{
   unsigned char status;
   long wordCnt;

   // reset Bus Master Error bit

   pio_writeBusMstrStatus( BM_SR_MASK_ERR );

   // Set command time out.

   tmr_set_timeout();

   // Select the drive - call the sub_select function.
   // Quit now if this fails.

   if ( sub_select( dev ) )
   {
      return 1;
   }

   // Set up all the registers except the command register.

   sub_setup_command();

   // Start the command by setting the Command register.  The drive
   // should immediately set BUSY status.

   pio_outbyte( CB_CMD, reg_cmd_info.cmd );

   // Waste some time by reading the alternate status a few times.
   // This gives the drive time to set BUSY in the status register on
   // really fast systems.  If we don't do this, a slow drive on a fast
   // system may not set BUSY fast enough and we would think it had
   // completed the command when it really had not even started the
   // command yet.

   DELAY400NS;

   // Loop to read each sector.

   while ( 1 )
   {
      // READ_LOOP:
      //
      // NOTE NOTE NOTE ...  The primary status register (1f7) MUST NOT be
      // read more than ONCE for each sector transferred!  When the
      // primary status register is read, the drive resets IRQ.  The
      // alternate status register (3f6) can be read any number of times.
      // After interrupt read the the primary status register ONCE
      // and transfer the 256 words (REP INSW).  AS SOON as BOTH the
      // primary status register has been read AND the last of the 256
      // words has been read, the drive is allowed to generate the next
      // IRQ (newer and faster drives could generate the next IRQ in
      // 50 microseconds or less).  If the primary status register is read
      // more than once, there is the possibility of a race between the
      // drive and the software and the next IRQ could be reset before
      // the system interrupt controller sees it.

      // Wait for interrupt -or- wait for not BUSY -or- wait for time out.

      sub_wait_poll( 34, 35 );

      // If polling or error read the status, otherwise
      // get the status that was read by the interrupt handler.

      if ( ( ! int_use_intr_flag ) || ( reg_cmd_info.ec ) )
         status = pio_inbyte( CB_STAT );
      else
         status = int_ata_status;

      // If there was a time out error, go to READ_DONE.

      if ( reg_cmd_info.ec )
         break;   // go to READ_DONE

      // If BSY=0 and DRQ=1, transfer the data,
      // even if we find out there is an error later.

      if ( ( status & ( CB_STAT_BSY | CB_STAT_DRQ ) ) == CB_STAT_DRQ )
      {

         // increment number of DRQ packets

         reg_cmd_info.drqPackets ++ ;

         // determine the number of sectors to transfer

         wordCnt = multiCnt ? multiCnt : 1;
         if ( wordCnt > numSect )
            wordCnt = numSect;
         wordCnt = wordCnt * 256;

         // Do the REP INSW to read the data for one DRQ block.

         reg_cmd_info.totalBytesXfer += ( wordCnt << 1 );
         pio_drq_block_in( CB_DATA, bufAddr, wordCnt );

         DELAY400NS;    // delay so device can get the status updated

         // Note: The drive should have dropped DATA REQUEST by now.  If there
         // are more sectors to transfer, BUSY should be active now (unless
         // there is an error).

         // Decrement the count of sectors to be transferred
         // and increment buffer address.

         numSect = numSect - ( multiCnt ? multiCnt : 1 );
         bufAddr = bufAddr + ( 512 * ( multiCnt ? multiCnt : 1 ) );
      }

      // So was there any error condition?

      if ( status & ( CB_STAT_BSY | CB_STAT_DF | CB_STAT_ERR ) )
      {
         reg_cmd_info.ec = 31;
         break;   // go to READ_DONE
      }

      // DRQ should have been set -- was it?

      if ( ( status & CB_STAT_DRQ ) == 0 )
      {
         reg_cmd_info.ec = 32;
         break;   // go to READ_DONE
      }

      // If all of the requested sectors have been transferred, make a
      // few more checks before we exit.

      if ( numSect < 1 )
      {
         // Since the drive has transferred all of the requested sectors
         // without error, the drive should not have BUSY, DEVICE FAULT,
         // DATA REQUEST or ERROR active now.

         status = pio_inbyte( CB_STAT );
         if ( status & ( CB_STAT_BSY | CB_STAT_DF | CB_STAT_DRQ | CB_STAT_ERR ) )
         {
            reg_cmd_info.ec = 33;
            break;   // go to READ_DONE
         }

         // All sectors have been read without error, go to READ_DONE.

         break;   // go to READ_DONE

      }

      // This is the end of the read loop.  If we get here, the loop is
      // repeated to read the next sector.  Go back to READ_LOOP.

   }

   // BMIDE Error=1?

   if ( pio_readBusMstrStatus() & BM_SR_MASK_ERR )
   {
      reg_cmd_info.ec = 78;                  // yes
   }

   // READ_DONE:

   // All done.  The return values of this function are described in
   // MINDRVR.H.

   if ( reg_cmd_info.ec )
      return 1;
   return 0;
}

//*************************************************************
//
// reg_pio_data_in_lba28() - Easy way to execute a PIO Data In command
//                           using an LBA sector address.
//
//*************************************************************

int reg_pio_data_in_lba28( unsigned char dev, unsigned char cmd,
                           unsigned int fr, unsigned int sc,
                           unsigned long lba,
                           unsigned char * bufAddr,
                           long numSect, int multiCnt )

{

   reg_cmd_info.cmd = cmd;
   reg_cmd_info.fr = fr;
   reg_cmd_info.sc = sc;
   reg_cmd_info.dh = (unsigned char) ( CB_DH_LBA | ( dev ? CB_DH_DEV1 : CB_DH_DEV0 ) );
   reg_cmd_info.dc = (unsigned char) ( int_use_intr_flag ? 0 : CB_DC_NIEN );
   reg_cmd_info.lbaSize = LBA28;
   reg_cmd_info.lbaHigh = 0L;
   reg_cmd_info.lbaLow = lba;