path: root/drivers/scsi/fd_mcs.c

/* fd_mcs.c -- Future Domain MCS 600/700 (or IBM OEM) driver
 *
 * FutureDomain MCS-600/700 v0.2 03/11/1998 by ZP Gu (zpg@castle.net)
 *
 * This driver is cloned from fdomain.* to specifically support
 * the Future Domain MCS 600/700 MCA SCSI adapters. Some PS/2s
 * also equipped with IBM Fast SCSI Adapter/A which is an OEM
 * of MCS 700.
 *
 * This driver also supports Reply SB16/SCSI card (the SCSI part).
 *
 * What makes this driver different is that this driver is MCA only
 * and it supports multiple adapters in the same system, IRQ 
 * sharing, some driver statistics, and maps highest SCSI id to sda.
 * All cards are auto-detected.
 *
 * Assumptions: TMC-1800/18C50/18C30, BIOS >= 3.4
 *
 * LILO command-line options:
 *   fd_mcs=<FIFO_COUNT>[,<FIFO_SIZE>]
 *
 * ********************************************************
 * Please see Copyrights/Comments in fdomain.* for credits.
 * Following is from fdomain.c for acknowledgement:
 *
 * Created: Sun May  3 18:53:19 1992 by faith@cs.unc.edu
 * Revised: Wed Oct  2 11:10:55 1996 by r.faith@ieee.org
 * Author: Rickard E. Faith, faith@cs.unc.edu
 * Copyright 1992, 1993, 1994, 1995, 1996 Rickard E. Faith
 *
 * $Id: fdomain.c,v 5.45 1996/10/02 15:13:06 root Exp $

 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2, or (at your option) any
 * later version.

 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.

 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 675 Mass Ave, Cambridge, MA 02139, USA.

 **************************************************************************

 NOTES ON USER DEFINABLE OPTIONS:

 DEBUG: This turns on the printing of various debug information.

 ENABLE_PARITY: This turns on SCSI parity checking.  With the current
 driver, all attached devices must support SCSI parity.  If none of your
 devices support parity, then you can probably get the driver to work by
 turning this option off.  I have no way of testing this, however, and it
 would appear that no one ever uses this option.

 FIFO_COUNT: The host adapter has an 8K cache (host adapters based on the
 18C30 chip have a 2k cache).  When this many 512 byte blocks are filled by
 the SCSI device, an interrupt will be raised.  Therefore, this could be as
 low as 0, or as high as 16.  Note, however, that values which are too high
 or too low seem to prevent any interrupts from occurring, and thereby lock
 up the machine.  I have found that 2 is a good number, but throughput may
 be increased by changing this value to values which are close to 2.
 Please let me know if you try any different values.
 [*****Now a runtime option*****]

 RESELECTION: This is no longer an option, since I gave up trying to
 implement it in version 4.x of this driver.  It did not improve
 performance at all and made the driver unstable (because I never found one
 of the two race conditions which were introduced by the multiple
 outstanding command code).  The instability seems a very high price to pay
 just so that you don't have to wait for the tape to rewind.  If you want
 this feature implemented, send me patches.  I'll be happy to send a copy
 of my (broken) driver to anyone who would like to see a copy.

 **************************************************************************/

#ifdef MODULE
#include <linux/module.h>
#endif

#include <linux/sched.h>
#include <linux/blk.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/proc_fs.h>
#include <linux/delay.h>
#include <linux/mca.h>
#include <linux/spinlock.h>
#include <asm/io.h>
#include <asm/system.h>

#include "scsi.h"
#include "hosts.h"
#include "fd_mcs.h"

#define DRIVER_VERSION "v0.2 by ZP Gu<zpg@castle.net>"
  
/* START OF USER DEFINABLE OPTIONS */

#define DEBUG            0	/* Enable debugging output */
#define ENABLE_PARITY    1	/* Enable SCSI Parity */
#define DO_DETECT        0	/* Do device detection here (see scsi.c) */

/* END OF USER DEFINABLE OPTIONS */

#if DEBUG
#define EVERY_ACCESS     0	/* Write a line on every scsi access */
#define ERRORS_ONLY      1	/* Only write a line if there is an error */
#define DEBUG_DETECT     1	/* Debug fd_mcs_detect() */
#define DEBUG_MESSAGES   1	/* Debug MESSAGE IN phase */
#define DEBUG_ABORT      1	/* Debug abort() routine */
#define DEBUG_RESET      1	/* Debug reset() routine */
#define DEBUG_RACE       1      /* Debug interrupt-driven race condition */
#else
#define EVERY_ACCESS     0	/* LEAVE THESE ALONE--CHANGE THE ONES ABOVE */
#define ERRORS_ONLY      0
#define DEBUG_DETECT     0
#define DEBUG_MESSAGES   0
#define DEBUG_ABORT      0
#define DEBUG_RESET      0
#define DEBUG_RACE       0
#endif

/* Errors are reported on the line, so we don't need to report them again */
#if EVERY_ACCESS
#undef ERRORS_ONLY
#define ERRORS_ONLY      0
#endif

#if ENABLE_PARITY
#define PARITY_MASK      0x08
#else
#define PARITY_MASK      0x00
#endif

enum chip_type {
  unknown          = 0x00,
  tmc1800          = 0x01,
  tmc18c50         = 0x02,
  tmc18c30         = 0x03,
};

enum {
  in_arbitration   = 0x02,
  in_selection     = 0x04,
  in_other         = 0x08,
  disconnect       = 0x10,
  aborted          = 0x20,
  sent_ident       = 0x40,
};

enum in_port_type {
  Read_SCSI_Data   =  0,
  SCSI_Status      =  1,
  TMC_Status       =  2,
  FIFO_Status      =  3,	/* tmc18c50/tmc18c30 only */
  Interrupt_Cond   =  4,	/* tmc18c50/tmc18c30 only */
  LSB_ID_Code      =  5,
  MSB_ID_Code      =  6,
  Read_Loopback    =  7,
  SCSI_Data_NoACK  =  8,
  Interrupt_Status =  9,
  Configuration1   = 10,
  Configuration2   = 11,	/* tmc18c50/tmc18c30 only */
  Read_FIFO        = 12,
  FIFO_Data_Count  = 14
};

enum out_port_type {
  Write_SCSI_Data  =  0,
  SCSI_Cntl        =  1,
  Interrupt_Cntl   =  2,
  SCSI_Mode_Cntl   =  3,
  TMC_Cntl         =  4,
  Memory_Cntl      =  5,	/* tmc18c50/tmc18c30 only */
  Write_Loopback   =  7,
  IO_Control       = 11,	/* tmc18c30 only */
  Write_FIFO       = 12
};

struct fd_hostdata {
  unsigned long     _bios_base;
  int               _bios_major;
  int               _bios_minor;
  volatile int      _in_command;
  Scsi_Cmnd         *_current_SC;
  enum chip_type    _chip;
  int               _adapter_mask;
  int               _fifo_count; /* Number of 512 byte blocks before INTR */

  char              _adapter_name[64];
#if DEBUG_RACE
  volatile int      _in_interrupt_flag;
#endif

  int               _SCSI_Mode_Cntl_port;
  int               _FIFO_Data_Count_port;
  int               _Interrupt_Cntl_port;
  int               _Interrupt_Status_port;
  int               _Interrupt_Cond_port;
  int               _Read_FIFO_port;
  int               _Read_SCSI_Data_port;
  int               _SCSI_Cntl_port;
  int               _SCSI_Data_NoACK_port;
  int               _SCSI_Status_port;
  int               _TMC_Cntl_port;
  int               _TMC_Status_port;
  int               _Write_FIFO_port;
  int               _Write_SCSI_Data_port;

  int               _FIFO_Size; /* = 0x2000;  8k FIFO for
				   pre-tmc18c30 chips */
  /* simple stats */
  int               _Bytes_Read;
  int               _Bytes_Written;
  int               _INTR_Processed;
};

#define FD_MAX_HOSTS 3		/* enough? */

#define HOSTDATA(shpnt) ((struct fd_hostdata *) shpnt->hostdata)
#define bios_base             (HOSTDATA(shpnt)->_bios_base)
#define bios_major            (HOSTDATA(shpnt)->_bios_major)
#define bios_minor            (HOSTDATA(shpnt)->_bios_minor)
#define in_command            (HOSTDATA(shpnt)->_in_command)
#define current_SC            (HOSTDATA(shpnt)->_current_SC)
#define chip                  (HOSTDATA(shpnt)->_chip)
#define adapter_mask          (HOSTDATA(shpnt)->_adapter_mask)
#define FIFO_COUNT            (HOSTDATA(shpnt)->_fifo_count)
#define adapter_name          (HOSTDATA(shpnt)->_adapter_name)
#if DEBUG_RACE
#define in_interrupt_flag     (HOSTDATA(shpnt)->_in_interrupt_flag)
#endif	                     
#define SCSI_Mode_Cntl_port   (HOSTDATA(shpnt)->_SCSI_Mode_Cntl_port)
#define FIFO_Data_Count_port  (HOSTDATA(shpnt)->_FIFO_Data_Count_port)
#define Interrupt_Cntl_port   (HOSTDATA(shpnt)->_Interrupt_Cntl_port)
#define Interrupt_Status_port (HOSTDATA(shpnt)->_Interrupt_Status_port)
#define Interrupt_Cond_port   (HOSTDATA(shpnt)->_Interrupt_Cond_port)
#define Read_FIFO_port        (HOSTDATA(shpnt)->_Read_FIFO_port)
#define Read_SCSI_Data_port   (HOSTDATA(shpnt)->_Read_SCSI_Data_port)
#define SCSI_Cntl_port        (HOSTDATA(shpnt)->_SCSI_Cntl_port)
#define SCSI_Data_NoACK_port  (HOSTDATA(shpnt)->_SCSI_Data_NoACK_port)
#define SCSI_Status_port      (HOSTDATA(shpnt)->_SCSI_Status_port)
#define TMC_Cntl_port         (HOSTDATA(shpnt)->_TMC_Cntl_port)
#define TMC_Status_port       (HOSTDATA(shpnt)->_TMC_Status_port)
#define Write_FIFO_port       (HOSTDATA(shpnt)->_Write_FIFO_port)
#define Write_SCSI_Data_port  (HOSTDATA(shpnt)->_Write_SCSI_Data_port)
#define FIFO_Size             (HOSTDATA(shpnt)->_FIFO_Size)
#define Bytes_Read            (HOSTDATA(shpnt)->_Bytes_Read)
#define Bytes_Written         (HOSTDATA(shpnt)->_Bytes_Written)
#define INTR_Processed        (HOSTDATA(shpnt)->_INTR_Processed)

struct fd_mcs_adapters_struct {
  char* name;
  int id;
  enum chip_type fd_chip;
  int fifo_size;
  int fifo_count;
};

#define REPLY_ID 0x5137

static struct fd_mcs_adapters_struct fd_mcs_adapters[] = {
  { "Future Domain SCSI Adapter MCS-700(18C50)",
    0x60e9,
    tmc18c50,
    0x2000,
    4 },
  { "Future Domain SCSI Adapter MCS-600/700(TMC-1800)",
    0x6127,
    tmc1800,
    0x2000,
    4 },
  { "Reply Sound Blaster/SCSI Adapter",
    REPLY_ID,
    tmc18c30,
    0x800,
    2 },
};

#define FD_BRDS sizeof(fd_mcs_adapters)/sizeof(struct fd_mcs_adapters_struct)

static void fd_mcs_intr( int irq, void *dev_id, struct pt_regs * regs );

static unsigned long addresses[] = {0xc8000, 0xca000, 0xce000, 0xde000};
static unsigned short ports[] = { 0x140, 0x150, 0x160, 0x170 };
static unsigned short ints[] = { 3, 5, 10, 11, 12, 14, 15, 0 };

/* host information */
static int found = 0;
static struct Scsi_Host *hosts[FD_MAX_HOSTS+1] = { NULL };

static int user_fifo_count = 0;
static int user_fifo_size = 0;

void fd_mcs_setup( char *str, int *ints )
{
  static int done_setup = 0;

  if (done_setup++ || ints[0] < 1 || ints[0] > 2 ||
      ints[1] < 1 || ints[1] > 16) {
    printk( "fd_mcs: usage: fd_mcs=FIFO_COUNT, FIFO_SIZE\n" );
  }

  user_fifo_count = ints[0] >= 1 ? ints[1] : 0;
  user_fifo_size  = ints[0] >= 2 ? ints[2] : 0;
}

static void print_banner( struct Scsi_Host *shpnt )
{
  printk( "scsi%d <fd_mcs>: ", shpnt->host_no);

  if (bios_base) {
    printk( "BIOS at 0x%lX", bios_base);
  } else {
    printk( "No BIOS");
  }

  printk( ", HostID %d, %s Chip, IRQ %d, IO 0x%lX\n",
          shpnt->this_id,
          chip == tmc18c50 ? "TMC-18C50"
             : (chip == tmc18c30 ? "TMC-18C30" :
                (chip == tmc1800 ? "TMC-1800" : "Unknown")),
          shpnt->irq,
          shpnt->io_port );
}


static void do_pause( unsigned amount )	/* Pause for amount*10 milliseconds */
{
  do {
    udelay(10*1000);
  } while (--amount);
}

inline static void fd_mcs_make_bus_idle( struct Scsi_Host *shpnt )
{
  outb( 0, SCSI_Cntl_port );
  outb( 0, SCSI_Mode_Cntl_port );
  if (chip == tmc18c50 || chip == tmc18c30)
    outb( 0x21 | PARITY_MASK, TMC_Cntl_port ); /* Clear forced intr. */
  else
    outb( 0x01 | PARITY_MASK, TMC_Cntl_port );
}

int fd_mcs_detect( Scsi_Host_Template *tpnt )
{
  int loop;
  struct Scsi_Host *shpnt;

  /* get id, port, bios, irq */
  int slot;
  u_char pos2, pos3, pos4;
  int id, port, irq;
  unsigned long bios;

  /* if not MCA machine, return */
  if (!MCA_bus)
    return 0;

  /* changeable? */
  id = 7;

  for( loop = 0; loop < FD_BRDS; loop++ ) {
    slot = 0;
    while ( MCA_NOTFOUND !=
	    (slot = mca_find_adapter(fd_mcs_adapters[loop].id,
				     slot)) ) {

      /* if we get this far, an adapter has been detected and is
	 enabled */

      printk("scsi  <fd_mcs>: %s at slot %d\n",
	     fd_mcs_adapters[loop].name, slot + 1 );

      pos2 = mca_read_stored_pos( slot, 2 );
      pos3 = mca_read_stored_pos( slot, 3 );
      pos4 = mca_read_stored_pos( slot, 4);

      /* ready for next probe */
      slot++;

      if (fd_mcs_adapters[loop].id == REPLY_ID) { /* reply card */
	static int reply_irq[] = {10, 11, 14, 15};

	bios = 0;		/* no bios */

	if (pos2 & 0x2)
	  port = ports[pos4 & 0x3];
	else
	  continue;

	/* can't really disable it, same as irq=10 */
	irq = reply_irq[((pos4 >> 2) & 0x1) + 2*((pos4 >> 4) & 0x1)];
      } else {
	bios = addresses[pos2 >> 6];
	port = ports[(pos2 >> 4) & 0x03];
	irq = ints[(pos2 >> 1) & 0x07];
      }

      if (irq) {
	/* claim the slot */
	mca_set_adapter_name( slot-1, fd_mcs_adapters[loop].name );

	/* check irq/region */
	if (check_region(port, 0x10) ||
	    request_irq(irq, fd_mcs_intr,
			SA_SHIRQ, "fd_mcs", hosts)) {
	  printk( "fd_mcs: check_region() || request_irq() failed, Skip it\n");

	  continue;
	}

	/* register */
	if (!(shpnt = scsi_register(tpnt, sizeof(struct fd_hostdata)))) {
	  printk( "fd_mcs: scsi_register() failed\n");
	  continue;
	}

	/* request I/O region */
	request_region( port, 0x10, "fd_mcs" );

	/* save name */
	strcpy(adapter_name, fd_mcs_adapters[loop].name);

	/* chip/fifo */
	chip = fd_mcs_adapters[loop].fd_chip;
	/* use boot time value if available */
	FIFO_COUNT =
	  user_fifo_count?user_fifo_count:fd_mcs_adapters[loop].fifo_count;
	FIFO_Size =
	  user_fifo_size?user_fifo_size:fd_mcs_adapters[loop].fifo_size;

#ifdef NOT_USED
	/* *************************************************** */
	/* Try to toggle 32-bit mode.  This only
	   works on an 18c30 chip.  (User reports
	   say this works, so we should switch to
	   it in the near future.) */
	outb( 0x80, port + IO_Control );
	if ((inb( port + Configuration2 ) & 0x80) == 0x80) {
	  outb( 0x00, port + IO_Control );
	  if ((inb( port + Configuration2 ) & 0x80) == 0x00) {
	    chip = tmc18c30;
	    FIFO_Size = 0x800;	/* 2k FIFO */

	    printk("FIRST: chip=%s, fifo_size=0x%x\n",
		   (chip == tmc18c30)?"tmc18c30":"tmc18c50", FIFO_Size);
	  }
	}

	/* That should have worked, but appears to
	   have problems.  Let's assume it is an
	   18c30 if the RAM is disabled. */

	if (inb( port + Configuration2 ) & 0x02) {
	  chip      = tmc18c30;
	  FIFO_Size = 0x800;	/* 2k FIFO */

	  printk("SECOND: chip=%s, fifo_size=0x%x\n",
		 (chip == tmc18c30)?"tmc18c30":"tmc18c50", FIFO_Size);
	}
	/* *************************************************** */	    
#endif

	/* IBM/ANSI scsi scan ordering */
	/* Stick this back in when the scsi.c changes are there */
	shpnt->reverse_ordering = 1;
	

	/* saving info */
	hosts[found++] = shpnt;

	shpnt->this_id = id;
	shpnt->irq = irq;
	shpnt->io_port = port;
	shpnt->n_io_port = 0x10;

	/* save */
	bios_base    = bios;
	adapter_mask = (1 << id);

	/* save more */
	SCSI_Mode_Cntl_port   = port + SCSI_Mode_Cntl;
	FIFO_Data_Count_port  = port + FIFO_Data_Count;
	Interrupt_Cntl_port   = port + Interrupt_Cntl;
	Interrupt_Status_port = port + Interrupt_Status;
	Interrupt_Cond_port   = port + Interrupt_Cond;
	Read_FIFO_port        = port + Read_FIFO;
	Read_SCSI_Data_port   = port + Read_SCSI_Data;
	SCSI_Cntl_port        = port + SCSI_Cntl;
	SCSI_Data_NoACK_port  = port + SCSI_Data_NoACK;
	SCSI_Status_port      = port + SCSI_Status;
	TMC_Cntl_port         = port + TMC_Cntl;
	TMC_Status_port       = port + TMC_Status;
	Write_FIFO_port       = port + Write_FIFO;
	Write_SCSI_Data_port  = port + Write_SCSI_Data;

	Bytes_Read     = 0;
	Bytes_Written  = 0;
	INTR_Processed = 0;

	/* say something */
	print_banner( shpnt );

	/* reset */
	outb( 1, SCSI_Cntl_port );
	do_pause( 2 );
	outb( 0, SCSI_Cntl_port );
	do_pause( 115 );
	outb( 0, SCSI_Mode_Cntl_port );
	outb( PARITY_MASK, TMC_Cntl_port );
	/* done reset */

#if DO_DETECT
	/* scan devices attached */
	{
	  const int     buflen = 255;
	  int           i, j, retcode;
	  Scsi_Cmnd     SCinit;
	  unsigned char do_inquiry[] =       { INQUIRY, 0, 0, 0, buflen, 0 };
	  unsigned char do_request_sense[] = { REQUEST_SENSE, 
					       0, 0, 0, buflen, 0 };
	  unsigned char do_read_capacity[] = { READ_CAPACITY,
					       0, 0, 0, 0, 0, 0, 0, 0, 0 };
	  unsigned char buf[buflen];

	  SCinit.request_buffer  = SCinit.buffer = buf;
	  SCinit.request_bufflen = SCinit.bufflen = sizeof(buf)-1;
	  SCinit.use_sg          = 0;
	  SCinit.lun             = 0;
	  SCinit.host            = shpnt;

	  printk( "fd_mcs: detection routine scanning for devices:\n" );
	  for (i = 0; i < 8; i++) {
	    if (i == shpnt->this_id)	/* Skip host adapter */
	      continue;
	    SCinit.target = i;
	    memcpy(SCinit.cmnd, do_request_sense,
		   sizeof(do_request_sense));
	    retcode = fd_mcs_command(&SCinit);
	    if (!retcode) {
	      memcpy(SCinit.cmnd, do_inquiry, sizeof(do_inquiry));
	      retcode = fd_mcs_command(&SCinit);
	      if (!retcode) {
		printk( "     SCSI ID %d: ", i );
		for (j = 8; j < (buf[4] < 32 ? buf[4] : 32); j++)
		  printk( "%c", buf[j] >= 20 ? buf[j] : ' ' );
		memcpy(SCinit.cmnd, do_read_capacity,
		       sizeof(do_read_capacity));
		retcode = fd_mcs_command(&SCinit);
		if (!retcode) {
		  unsigned long blocks, size, capacity;
	       
		  blocks = (buf[0] << 24) | (buf[1] << 16)
		    | (buf[2] << 8) | buf[3];
		  size = (buf[4] << 24) | (buf[5] << 16) | 
		    (buf[6] << 8) | buf[7];
		  capacity = +( +(blocks / 1024L) * +(size * 10L)) / 1024L;
	       
		  printk( "%lu MB (%lu byte blocks)\n",
			  ((capacity + 5L) / 10L), size );
		}
	      }
	    }
	  }
	}
#endif
      }
    }

    if (found == FD_MAX_HOSTS) {
      printk( "fd_mcs: detecting reached max=%d host adapters.\n",
	      FD_MAX_HOSTS);
      break;
    }
  }

  return found;
}

const char *fd_mcs_info(struct Scsi_Host *shpnt)
{
  return adapter_name;
}

static int TOTAL_INTR = 0;

/*
 * inout : decides on the direction of the dataflow and the meaning of the 
 *         variables
 * buffer: If inout==FALSE data is being written to it else read from it
 * *start: If inout==FALSE start of the valid data in the buffer
 * offset: If inout==FALSE offset from the beginning of the imaginary file 
 *         from which we start writing into the buffer
 * length: If inout==FALSE max number of bytes to be written into the buffer 
 *         else number of bytes in the buffer
 */
int fd_mcs_proc_info( char *buffer, char **start, off_t offset,
		      int length, int hostno, int inout )
{
  struct Scsi_Host *shpnt;
  int    len = 0;
  int    i;

  if (inout)
    return(-ENOSYS);

  *start = buffer + offset;

  for (i = 0; hosts[i] && hosts[i]->host_no != hostno; i++);
  shpnt = hosts[i];

  if (!shpnt) {
    return(-ENOENT);
  } else {
    len += sprintf(buffer+len, "Future Domain MCS-600/700 Driver %s\n",
		   DRIVER_VERSION);

    len += sprintf(buffer+len, "HOST #%d: %s\n",
		   hostno, adapter_name);

    len += sprintf(buffer+len, "FIFO Size=0x%x, FIFO Count=%d\n",
		   FIFO_Size, FIFO_COUNT);

    len += sprintf(buffer+len, "DriverCalls=%d, Interrupts=%d, BytesRead=%d, BytesWrite=%d\n\n",
		   TOTAL_INTR, INTR_Processed, Bytes_Read, Bytes_Written);
  }

  if ((len -= offset) <= 0)
    return 0;
  if (len > length) 
    len = length;
  return len;
}
   
static int fd_mcs_select(struct Scsi_Host *shpnt, int target )
{
  int           status;
  unsigned long timeout;

  outb( 0x82, SCSI_Cntl_port ); /* Bus Enable + Select */
  outb( adapter_mask | (1 << target), SCSI_Data_NoACK_port );

  /* Stop arbitration and enable parity */
  outb( PARITY_MASK, TMC_Cntl_port ); 

  timeout = 350;		/* 350mS -- because of timeouts
				   (was 250mS) */

  do {
    status = inb( SCSI_Status_port ); /* Read adapter status */
    if (status & 1) {			/* Busy asserted */
      /* Enable SCSI Bus (on error, should make bus idle with 0) */
      outb( 0x80, SCSI_Cntl_port );
      return 0;
    }
    udelay(1000);		/* wait one msec */
  } while (--timeout);

  /* Make bus idle */
  fd_mcs_make_bus_idle(shpnt);
#if EVERY_ACCESS
  if (!target) printk( "Selection failed\n" );
#endif
#if ERRORS_ONLY
  if (!target) {
    static int flag = 0;

    if (!flag) /* Skip first failure for all chips. */
      ++flag;
    else
      printk( "fd_mcs: Selection failed\n" );
  }
#endif
  return 1;
}

static void my_done( struct Scsi_Host *shpnt, int error )
{
  if (in_command) {
    in_command = 0;
    outb( 0x00, Interrupt_Cntl_port );
    fd_mcs_make_bus_idle(shpnt);
    current_SC->result = error;
    current_SC->scsi_done( current_SC );
  } else {
    panic( "fd_mcs: my_done() called outside of command\n" );
  }
#if DEBUG_RACE
  in_interrupt_flag = 0;
#endif
}

/* only my_done needs to be protected  */
static void fd_mcs_intr( int irq, void *dev_id, struct pt_regs * regs )
{
  unsigned long flags;
  int      status;
  int      done = 0;
  unsigned data_count, tmp_count;

  int i = 0;
  struct Scsi_Host *shpnt;

  TOTAL_INTR++;

  /* search for one adapter-response on shared interrupt */
  while ((shpnt = hosts[i++])) {
    if ((inb(TMC_Status_port)) & 1)
      break;
  }
 
  /* return if some other device on this IRQ caused the interrupt */
  if (!shpnt) {
    return;
  }

  INTR_Processed++;

  outb( 0x00, Interrupt_Cntl_port );

  /* Abort calls my_done, so we do nothing here. */
  if (current_SC->SCp.phase & aborted) {
#if DEBUG_ABORT
    printk( "Interrupt after abort, ignoring\n" );
#endif
    /* return; */
  }

#if DEBUG_RACE
  ++in_interrupt_flag;
#endif

  if (current_SC->SCp.phase & in_arbitration) {
    status = inb( TMC_Status_port );        /* Read adapter status */
    if (!(status & 0x02)) {
#if EVERY_ACCESS
      printk( " AFAIL " );
#endif
      spin_lock_irqsave(&io_request_lock, flags);
      my_done( shpnt, DID_BUS_BUSY << 16 );
      spin_unlock_irqrestore(&io_request_lock, flags);
      return;
    }
    current_SC->SCp.phase = in_selection;
      
    outb( 0x40 | FIFO_COUNT, Interrupt_Cntl_port );

    outb( 0x82, SCSI_Cntl_port ); /* Bus Enable + Select */
    outb( adapter_mask | (1 << current_SC->target), SCSI_Data_NoACK_port );
      
    /* Stop arbitration and enable parity */
    outb( 0x10 | PARITY_MASK, TMC_Cntl_port );
#if DEBUG_RACE
    in_interrupt_flag = 0;
#endif
    return;
  } else if (current_SC->SCp.phase & in_selection) {
    status = inb( SCSI_Status_port );
    if (!(status & 0x01)) {
      /* Try again, for slow devices */
      if (fd_mcs_select(shpnt, current_SC->target )) {
#if EVERY_ACCESS
	printk( " SFAIL " );
#endif
	spin_lock_irqsave(&io_request_lock, flags);
	my_done( shpnt, DID_NO_CONNECT << 16 );
	spin_unlock_irqrestore(&io_request_lock, flags);
	return;
      } else {
#if EVERY_ACCESS
	printk( " AltSel " );
#endif
	/* Stop arbitration and enable parity */
	outb( 0x10 | PARITY_MASK, TMC_Cntl_port );
      }
    }
    current_SC->SCp.phase = in_other;
    outb( 0x90 | FIFO_COUNT, Interrupt_Cntl_port );
    outb( 0x80, SCSI_Cntl_port );
#if DEBUG_RACE
    in_interrupt_flag = 0;
#endif
    return;
  }
   
  /* current_SC->SCp.phase == in_other: this is the body of the routine */
   
  status = inb( SCSI_Status_port );
   
  if (status & 0x10) {	/* REQ */
      
    switch (status & 0x0e) {
       
    case 0x08:		/* COMMAND OUT */
      outb( current_SC->cmnd[current_SC->SCp.sent_command++],
	    Write_SCSI_Data_port );
#if EVERY_ACCESS
      printk( "CMD = %x,",
	      current_SC->cmnd[ current_SC->SCp.sent_command - 1] );
#endif
      break;
    case 0x00:		/* DATA OUT -- tmc18c50/tmc18c30 only */
      if (chip != tmc1800 && !current_SC->SCp.have_data_in) {
	current_SC->SCp.have_data_in = -1;
	outb( 0xd0 | PARITY_MASK, TMC_Cntl_port );
      }
      break;
    case 0x04:		/* DATA IN -- tmc18c50/tmc18c30 only */
      if (chip != tmc1800 && !current_SC->SCp.have_data_in) {
	current_SC->SCp.have_data_in = 1;
	outb( 0x90 | PARITY_MASK, TMC_Cntl_port );
      }
      break;
    case 0x0c:		/* STATUS IN */
      current_SC->SCp.Status = inb( Read_SCSI_Data_port );
#if EVERY_ACCESS
      printk( "Status = %x, ", current_SC->SCp.Status );
#endif
#if ERRORS_ONLY
      if (current_SC->SCp.Status
	  && current_SC->SCp.Status != 2
	  && current_SC->SCp.Status != 8) {
	printk( "ERROR fd_mcs: target = %d, command = %x, status = %x\n",
		current_SC->target,
		current_SC->cmnd[0],
		current_SC->SCp.Status );
      }
#endif
      break;
    case 0x0a:		/* MESSAGE OUT */
      outb( MESSAGE_REJECT, Write_SCSI_Data_port ); /* Reject */
      break;
    case 0x0e:		/* MESSAGE IN */
      current_SC->SCp.Message = inb( Read_SCSI_Data_port );
#if EVERY_ACCESS
      printk( "Message = %x, ", current_SC->SCp.Message );
#endif
      if (!current_SC->SCp.Message) ++done;
#if DEBUG_MESSAGES || EVERY_ACCESS
      if (current_SC->SCp.Message) {
	printk( "fd_mcs: message = %x\n", current_SC->SCp.Message );
      }
#endif
      break;
    }
  }

  if (chip == tmc1800
      && !current_SC->SCp.have_data_in
      && (current_SC->SCp.sent_command
	  >= current_SC->cmd_len)) {
    /* We have to get the FIFO direction
       correct, so I've made a table based
       on the SCSI Standard of which commands
       appear to require a DATA OUT phase.
       */
    /*
      p. 94: Command for all device types
      CHANGE DEFINITION            40 DATA OUT
      COMPARE                      39 DATA OUT
      COPY                         18 DATA OUT
      COPY AND VERIFY              3a DATA OUT
      INQUIRY                      12 
      LOG SELECT                   4c DATA OUT
      LOG SENSE                    4d
      MODE SELECT (6)              15 DATA OUT
      MODE SELECT (10)             55 DATA OUT
      MODE SENSE (6)               1a
      MODE SENSE (10)              5a
      READ BUFFER                  3c
      RECEIVE DIAGNOSTIC RESULTS   1c
      REQUEST SENSE                03
      SEND DIAGNOSTIC              1d DATA OUT
      TEST UNIT READY              00
      WRITE BUFFER                 3b DATA OUT

      p.178: Commands for direct-access devices (not listed on p. 94)
      FORMAT UNIT                  04 DATA OUT
      LOCK-UNLOCK CACHE            36
      PRE-FETCH                    34
      PREVENT-ALLOW MEDIUM REMOVAL 1e
      READ (6)/RECEIVE             08
      READ (10)                    3c
      READ CAPACITY                25
      READ DEFECT DATA (10)        37
      READ LONG                    3e
      REASSIGN BLOCKS              07 DATA OUT
      RELEASE                      17
      RESERVE                      16 DATA OUT
      REZERO UNIT/REWIND           01
      SEARCH DATA EQUAL (10)       31 DATA OUT
      SEARCH DATA HIGH (10)        30 DATA OUT
      SEARCH DATA LOW (10)         32 DATA OUT
      SEEK (6)                     0b
      SEEK (10)                    2b
      SET LIMITS (10)              33
      START STOP UNIT              1b
      SYNCHRONIZE CACHE            35
      VERIFY (10)                  2f
      WRITE (6)/PRINT/SEND         0a DATA OUT
      WRITE (10)/SEND              2a DATA OUT
      WRITE AND VERIFY (10)        2e DATA OUT
      WRITE LONG                   3f DATA OUT
      WRITE SAME                   41 DATA OUT ?

      p. 261: Commands for sequential-access devices (not previously listed)
      ERASE                        19
      LOAD UNLOAD                  1b
      LOCATE                       2b
      READ BLOCK LIMITS            05
      READ POSITION                34
      READ REVERSE                 0f
      RECOVER BUFFERED DATA        14
      SPACE                        11
      WRITE FILEMARKS              10 ?

      p. 298: Commands for printer devices (not previously listed)
      ****** NOT SUPPORTED BY THIS DRIVER, since 0b is SEEK (6) *****
      SLEW AND PRINT               0b DATA OUT  -- same as seek
      STOP PRINT                   1b
      SYNCHRONIZE BUFFER           10

      p. 315: Commands for processor devices (not previously listed)
	
      p. 321: Commands for write-once devices (not previously listed)
      MEDIUM SCAN                  38
      READ (12)                    a8
      SEARCH DATA EQUAL (12)       b1 DATA OUT
      SEARCH DATA HIGH (12)        b0 DATA OUT
      SEARCH DATA LOW (12)         b2 DATA OUT
      SET LIMITS (12)              b3
      VERIFY (12)                  af
      WRITE (12)                   aa DATA OUT
      WRITE AND VERIFY (12)        ae DATA OUT

      p. 332: Commands for CD-ROM devices (not previously listed)
      PAUSE/RESUME                 4b
      PLAY AUDIO (10)              45
      PLAY AUDIO (12)              a5
      PLAY AUDIO MSF               47
      PLAY TRACK RELATIVE (10)     49
      PLAY TRACK RELATIVE (12)     a9
      READ HEADER                  44
      READ SUB-CHANNEL             42
      READ TOC                     43

      p. 370: Commands for scanner devices (not previously listed)
      GET DATA BUFFER STATUS       34
      GET WINDOW                   25
      OBJECT POSITION              31
      SCAN                         1b
      SET WINDOW                   24 DATA OUT

      p. 391: Commands for optical memory devices (not listed)
      ERASE (10)                   2c
      ERASE (12)                   ac
      MEDIUM SCAN                  38 DATA OUT
      READ DEFECT DATA (12)        b7
      READ GENERATION              29
      READ UPDATED BLOCK           2d
      UPDATE BLOCK                 3d DATA OUT

      p. 419: Commands for medium changer devices (not listed)
      EXCHANGE MEDIUM              46
      INITIALIZE ELEMENT STATUS    07
      MOVE MEDIUM                  a5
      POSITION TO ELEMENT          2b
      READ ELEMENT STATUS          b8
      REQUEST VOL. ELEMENT ADDRESS b5
      SEND VOLUME TAG              b6 DATA OUT

      p. 454: Commands for communications devices (not listed previously)
      GET MESSAGE (6)              08
      GET MESSAGE (10)             28
      GET MESSAGE (12)             a8
      */
	
    switch (current_SC->cmnd[0]) {
    case CHANGE_DEFINITION: case COMPARE:         case COPY:
    case COPY_VERIFY:       case LOG_SELECT:      case MODE_SELECT:
    case MODE_SELECT_10:    case SEND_DIAGNOSTIC: case WRITE_BUFFER:

    case FORMAT_UNIT:       case REASSIGN_BLOCKS: case RESERVE:
    case SEARCH_EQUAL:      case SEARCH_HIGH:     case SEARCH_LOW:
    case WRITE_6:           case WRITE_10:        case WRITE_VERIFY:
    case 0x3f:              case 0x41:

    case 0xb1:              case 0xb0:            case 0xb2:
    case 0xaa:              case 0xae:

    case 0x24:

    case 0x38:              case 0x3d:

    case 0xb6:
	 
    case 0xea:		/* alternate number for WRITE LONG */
	 
      current_SC->SCp.have_data_in = -1;
      outb( 0xd0 | PARITY_MASK, TMC_Cntl_port );
      break;

    case 0x00:
    default:
	 
      current_SC->SCp.have_data_in = 1;
      outb( 0x90 | PARITY_MASK, TMC_Cntl_port );
      break;
    }
  }

  if (current_SC->SCp.have_data_in == -1) { /* DATA OUT */
    while ( (data_count = FIFO_Size - inw( FIFO_Data_Count_port )) > 512 ) {
#if EVERY_ACCESS
      printk( "DC=%d, ", data_count ) ;
#endif
      if (data_count > current_SC->SCp.this_residual)
	data_count = current_SC->SCp.this_residual;
      if (data_count > 0) {
#if EVERY_ACCESS
	printk( "%d OUT, ", data_count );
#endif
	if (data_count == 1) {
	  Bytes_Written++;

	  outb( *current_SC->SCp.ptr++, Write_FIFO_port );
	  --current_SC->SCp.this_residual;
	} else {
	  data_count >>= 1;
	  tmp_count = data_count << 1;
	  outsw( Write_FIFO_port, current_SC->SCp.ptr, data_count );
	  current_SC->SCp.ptr += tmp_count;
	  Bytes_Written += tmp_count;
	  current_SC->SCp.this_residual -= tmp_count;
	}
      }
      if (!current_SC->SCp.this_residual) {
	if (current_SC->SCp.buffers_residual) {
	  --current_SC->SCp.buffers_residual;
	  ++current_SC->SCp.buffer;
	  current_SC->SCp.ptr = current_SC->SCp.buffer->address;
	  current_SC->SCp.this_residual = current_SC->SCp.buffer->length;
	} else
	  break;
      }
    }
  } else if (current_SC->SCp.have_data_in == 1) { /* DATA IN */
    while ((data_count = inw( FIFO_Data_Count_port )) > 0) {
#if EVERY_ACCESS
      printk( "DC=%d, ", data_count );
#endif
      if (data_count > current_SC->SCp.this_residual)
	data_count = current_SC->SCp.this_residual;
      if (data_count) {
#if EVERY_ACCESS
	printk( "%d IN, ", data_count );
#endif
	if (data_count == 1) {
	  Bytes_Read++;
	  *current_SC->SCp.ptr++ = inb( Read_FIFO_port );
	  --current_SC->SCp.this_residual;
	} else {
	  data_count >>= 1; /* Number of words */
	  tmp_count = data_count << 1;
	  insw( Read_FIFO_port, current_SC->SCp.ptr, data_count );
	  current_SC->SCp.ptr += tmp_count;
	  Bytes_Read += tmp_count;
	  current_SC->SCp.this_residual -= tmp_count;
	}
      }
      if (!current_SC->SCp.this_residual
	  && current_SC->SCp.buffers_residual) {
	--current_SC->SCp.buffers_residual;
	++current_SC->SCp.buffer;
	current_SC->SCp.ptr = current_SC->SCp.buffer->address;
	current_SC->SCp.this_residual = current_SC->SCp.buffer->length;
      }
    }
  }
   
  if (done) {
#if EVERY_ACCESS
    printk( " ** IN DONE %d ** ", current_SC->SCp.have_data_in );
#endif

#if ERRORS_ONLY
    if (current_SC->cmnd[0] == REQUEST_SENSE && !current_SC->SCp.Status) {
      if ((unsigned char)(*((char *)current_SC->request_buffer+2)) & 0x0f) {
	unsigned char key;
	unsigned char code;
	unsigned char qualifier;

	key = (unsigned char)(*((char *)current_SC->request_buffer + 2))
	  & 0x0f;
	code = (unsigned char)(*((char *)current_SC->request_buffer + 12));
	qualifier = (unsigned char)(*((char *)current_SC->request_buffer
				      + 13));

	if (key != UNIT_ATTENTION
	    && !(key == NOT_READY
		 && code == 0x04
		 && (!qualifier || qualifier == 0x02 || qualifier == 0x01))
	    && !(key == ILLEGAL_REQUEST && (code == 0x25
					    || code == 0x24
					    || !code)))
		  
	  printk( "fd_mcs: REQUEST SENSE "
		  "Key = %x, Code = %x, Qualifier = %x\n",
		  key, code, qualifier );
      }
    }
#endif
#if EVERY_ACCESS
    printk( "BEFORE MY_DONE. . ." );
#endif
    spin_lock_irqsave(&io_request_lock, flags);
    my_done( shpnt,
	     (current_SC->SCp.Status & 0xff)
	     | ((current_SC->SCp.Message & 0xff) << 8) | (DID_OK << 16) );
    spin_unlock_irqrestore(&io_request_lock, flags);
#if EVERY_ACCESS
    printk( "RETURNING.\n" );
#endif
      
  } else {
    if (current_SC->SCp.phase & disconnect) {
      outb( 0xd0 | FIFO_COUNT, Interrupt_Cntl_port );
      outb( 0x00, SCSI_Cntl_port );
    } else {
      outb( 0x90 | FIFO_COUNT, Interrupt_Cntl_port );
    }
  }
#if DEBUG_RACE
  in_interrupt_flag = 0;
#endif
  return;
}

int fd_mcs_release(struct Scsi_Host *shpnt)
{
  int i, this_host, irq_usage;

  release_region(shpnt->io_port, shpnt->n_io_port);

  this_host = -1;
  irq_usage = 0;
  for (i = 0; i < found; i++) {
    if (shpnt == hosts[i])
      this_host = i;
    if (shpnt->irq == hosts[i]->irq)
      irq_usage++;
  }

  /* only for the last one */
  if (1 == irq_usage)
    free_irq(shpnt->irq, hosts);

  found--;

  for (i = this_host; i < found; i++)
    hosts[i] = hosts[i+1];

  hosts[found] = NULL;

  return 0;
}

int fd_mcs_queue( Scsi_Cmnd * SCpnt, void (*done)(Scsi_Cmnd *))
{
  struct Scsi_Host *shpnt = SCpnt->host;

  if (in_command) {
    panic( "fd_mcs: fd_mcs_queue() NOT REENTRANT!\n" );
  }
#if EVERY_ACCESS
  printk( "queue: target = %d cmnd = 0x%02x pieces = %d size = %u\n",
	  SCpnt->target,
	  *(unsigned char *)SCpnt->cmnd,
	  SCpnt->use_sg,
	  SCpnt->request_bufflen );
#endif

  fd_mcs_make_bus_idle(shpnt);

  SCpnt->scsi_done = done;	/* Save this for the done function */
  current_SC       = SCpnt;

  /* Initialize static data */

  if (current_SC->use_sg) {
    current_SC->SCp.buffer =
      (struct scatterlist *)current_SC->request_buffer;
    current_SC->SCp.ptr              = current_SC->SCp.buffer->address;
    current_SC->SCp.this_residual    = current_SC->SCp.buffer->length;
    current_SC->SCp.buffers_residual = current_SC->use_sg - 1;
  } else {
    current_SC->SCp.ptr              = (char *)current_SC->request_buffer;
    current_SC->SCp.this_residual    = current_SC->request_bufflen;
    current_SC->SCp.buffer           = NULL;
    current_SC->SCp.buffers_residual = 0;
  }
	 
   
  current_SC->SCp.Status              = 0;
  current_SC->SCp.Message             = 0;
  current_SC->SCp.have_data_in        = 0;
  current_SC->SCp.sent_command        = 0;
  current_SC->SCp.phase               = in_arbitration;

  /* Start arbitration */
  outb( 0x00, Interrupt_Cntl_port );
  outb( 0x00, SCSI_Cntl_port );              /* Disable data drivers */
  outb( adapter_mask, SCSI_Data_NoACK_port ); /* Set our id bit */
  in_command = 1;
  outb( 0x20, Interrupt_Cntl_port );
  outb( 0x14 | PARITY_MASK, TMC_Cntl_port ); /* Start arbitration */

  return 0;
}

static void internal_done( Scsi_Cmnd *SCpnt )
{
  /* flag it done */
  SCpnt->host_scribble = (unsigned char *)1;
}

int fd_mcs_command( Scsi_Cmnd *SCpnt )
{
  fd_mcs_queue( SCpnt, internal_done );
  /* host_scribble is used for status here */
  SCpnt->host_scribble = NULL;
  while (!SCpnt->host_scribble)
    barrier();
  return SCpnt->result;
}

#if DEBUG_ABORT || DEBUG_RESET
static void fd_mcs_print_info( Scsi_Cmnd *SCpnt )
{
  unsigned int imr;
  unsigned int irr;
  unsigned int isr;
  struct Scsi_Host *shpnt = SCpnt->host;

  if (!SCpnt || !SCpnt->host) {
    printk( "fd_mcs: cannot provide detailed information\n" );
  }
   
  printk( "%s\n", fd_mcs_info( SCpnt->host ) );
  print_banner( SCpnt->host );
  switch (SCpnt->SCp.phase) {
  case in_arbitration: printk( "arbitration " ); break;
  case in_selection:   printk( "selection " );   break;
  case in_other:       printk( "other " );       break;
  default:             printk( "unknown " );     break;
  }

  printk( "(%d), target = %d cmnd = 0x%02x pieces = %d size = %u\n",
	  SCpnt->SCp.phase,
	  SCpnt->target,
	  *(unsigned char *)SCpnt->cmnd,
	  SCpnt->use_sg,
	  SCpnt->request_bufflen );
  printk( "sent_command = %d, have_data_in = %d, timeout = %d\n",
	  SCpnt->SCp.sent_command,
	  SCpnt->SCp.have_data_in,
	  SCpnt->timeout );
#if DEBUG_RACE
  printk( "in_interrupt_flag = %d\n", in_interrupt_flag );
#endif

  imr = (inb( 0x0a1 ) << 8) + inb( 0x21 );
  outb( 0x0a, 0xa0 );
  irr = inb( 0xa0 ) << 8;
  outb( 0x0a, 0x20 );
  irr += inb( 0x20 );
  outb( 0x0b, 0xa0 );
  isr = inb( 0xa0 ) << 8;
  outb( 0x0b, 0x20 );
  isr += inb( 0x20 );

  /* Print out interesting information */
  printk( "IMR = 0x%04x", imr );
  if (imr & (1 << shpnt->irq))
    printk( " (masked)" );
  printk( ", IRR = 0x%04x, ISR = 0x%04x\n", irr, isr );

  printk( "SCSI Status      = 0x%02x\n", inb( SCSI_Status_port ) );
  printk( "TMC Status       = 0x%02x", inb( TMC_Status_port ) );
  if (inb( TMC_Status_port ) & 1)
    printk( " (interrupt)" );
  printk( "\n" );
  printk( "Interrupt Status = 0x%02x", inb( Interrupt_Status_port ) );
  if (inb( Interrupt_Status_port ) & 0x08)
    printk( " (enabled)" );
  printk( "\n" );
  if (chip == tmc18c50 || chip == tmc18c30) {
    printk( "FIFO Status      = 0x%02x\n", inb( shpnt->io_port + FIFO_Status ) );
    printk( "Int. Condition   = 0x%02x\n",
	    inb( shpnt->io_port + Interrupt_Cond ) );
  }
  printk( "Configuration 1  = 0x%02x\n", inb( shpnt->io_port + Configuration1 ) );
  if (chip == tmc18c50 || chip == tmc18c30)
    printk( "Configuration 2  = 0x%02x\n",
	    inb( shpnt->io_port + Configuration2 ) );
}
#endif

int fd_mcs_abort( Scsi_Cmnd *SCpnt)
{
  struct Scsi_Host *shpnt = SCpnt->host;

  unsigned long flags;
#if EVERY_ACCESS || ERRORS_ONLY || DEBUG_ABORT
  printk( "fd_mcs: abort " );
#endif

  save_flags( flags );
  cli();
  if (!in_command) {
#if EVERY_ACCESS || ERRORS_ONLY
    printk( " (not in command)\n" );
#endif
    restore_flags( flags );
    return SCSI_ABORT_NOT_RUNNING;
  } else printk( "\n" );

#if DEBUG_ABORT
  fd_mcs_print_info( SCpnt );
#endif

  fd_mcs_make_bus_idle(shpnt);

  current_SC->SCp.phase |= aborted;

  current_SC->result = DID_ABORT << 16;

  restore_flags( flags );
   
  /* Aborts are not done well. . . */
  spin_lock_irqsave(&io_request_lock, flags);
  my_done( shpnt, DID_ABORT << 16 );
  spin_unlock_irqrestore(&io_request_lock, flags);

  return SCSI_ABORT_SUCCESS;
}

int fd_mcs_reset( Scsi_Cmnd *SCpnt, unsigned int reset_flags )
{
  struct Scsi_Host *shpnt = SCpnt->host;

#if DEBUG_RESET
  static int called_once = 0;
#endif

#if ERRORS_ONLY
  if (SCpnt) printk( "fd_mcs: SCSI Bus Reset\n" );
#endif

#if DEBUG_RESET
  if (called_once) fd_mcs_print_info( current_SC );
  called_once = 1;
#endif
   
  outb( 1, SCSI_Cntl_port );
  do_pause( 2 );
  outb( 0, SCSI_Cntl_port );
  do_pause( 115 );
  outb( 0, SCSI_Mode_Cntl_port );
  outb( PARITY_MASK, TMC_Cntl_port );

  /* Unless this is the very first call (i.e., SCPnt == NULL), everything
     is probably hosed at this point.  We will, however, try to keep
     things going by informing the high-level code that we need help. */

  return SCSI_RESET_WAKEUP;
}

#include "sd.h"
#include <scsi/scsi_ioctl.h>

int fd_mcs_biosparam( Scsi_Disk *disk, kdev_t dev, int *info_array )
{
  int              drive;
  unsigned char    buf[512 + sizeof( int ) * 2];
  int		    size      = disk->capacity;
  int              *sizes    = (int *)buf;
  unsigned char    *data     = (unsigned char *)(sizes + 2);
  unsigned char    do_read[] = { READ_6, 0, 0, 0, 1, 0 };
  int              retcode;

  /* BIOS >= 3.4 for MCA cards */
  drive = MINOR(dev) / 16;

  /* This algorithm was provided by Future Domain (much thanks!). */

  sizes[0] = 0;		/* zero bytes out */
  sizes[1] = 512;		/* one sector in */
  memcpy( data, do_read, sizeof( do_read ) );
  retcode = kernel_scsi_ioctl( disk->device,
			       SCSI_IOCTL_SEND_COMMAND,
			       (void *)buf );
  if (!retcode				    /* SCSI command ok */
      && data[511] == 0xaa && data[510] == 0x55 /* Partition table valid */
      && data[0x1c2]) {			    /* Partition type */

    /* The partition table layout is as follows:

	 Start: 0x1b3h
	 Offset: 0 = partition status
	 1 = starting head
	 2 = starting sector and cylinder (word, encoded)
	 4 = partition type
	 5 = ending head
	 6 = ending sector and cylinder (word, encoded)
	 8 = starting absolute sector (double word)
	 c = number of sectors (double word)
	 Signature: 0x1fe = 0x55aa

	 So, this algorithm assumes:
	 1) the first partition table is in use,
	 2) the data in the first entry is correct, and
	 3) partitions never divide cylinders

	 Note that (1) may be FALSE for NetBSD (and other BSD flavors),
	 as well as for Linux.  Note also, that Linux doesn't pay any
	 attention to the fields that are used by this algorithm -- it
	 only uses the absolute sector data.  Recent versions of Linux's
	 fdisk(1) will fill this data in correctly, and forthcoming
	 versions will check for consistency.

	 Checking for a non-zero partition type is not part of the
	 Future Domain algorithm, but it seemed to be a reasonable thing
	 to do, especially in the Linux and BSD worlds. */

    info_array[0] = data[0x1c3] + 1;	    /* heads */
    info_array[1] = data[0x1c4] & 0x3f;	    /* sectors */
  } else {

    /* Note that this new method guarantees that there will always be
	 less than 1024 cylinders on a platter.  This is good for drives
	 up to approximately 7.85GB (where 1GB = 1024 * 1024 kB). */

    if ((unsigned int)size >= 0x7e0000U) {
      info_array[0] = 0xff; /* heads   = 255 */
      info_array[1] = 0x3f; /* sectors =  63 */
    } else if ((unsigned int)size >= 0x200000U) {
      info_array[0] = 0x80; /* heads   = 128 */
      info_array[1] = 0x3f; /* sectors =  63 */
    } else {
      info_array[0] = 0x40; /* heads   =  64 */
      info_array[1] = 0x20; /* sectors =  32 */
    }
  }
  /* For both methods, compute the cylinders */
  info_array[2] = (unsigned int)size / (info_array[0] * info_array[1] );

   
  return 0;
}

/* Eventually this will go into an include file, but this will be later */
static Scsi_Host_Template driver_template = FD_MCS;

#include "scsi_module.c"