/*
   Test, if port_base is valid.
 */
static int aha152x_porttest(int port_base)
{
  int i;

  if(check_region(port_base, TEST-SCSISEQ))
    return 0;

  SETPORT( DMACNTRL1, 0 );          /* reset stack pointer */
  for(i=0; i<16; i++)
    SETPORT( STACK, i );

  SETPORT( DMACNTRL1, 0 );          /* reset stack pointer */
  for(i=0; i<16 && GETPORT(STACK)==i; i++)
    ;

  return(i==16);
}

int aha152x_detect(int hostno)
{
  int                 i, j,  ok;
  aha152x_config      conf;
  struct sigaction    sa;
  int                 interrupt_level;
  
#if defined(DEBUG_RACE)
  enter_driver("detect");
#endif
  
  printk("aha152x: Probing: ");

  if(setup_called)
    {
      printk("processing commandline: ");
   
      if(setup_called!=4)
        {
          printk("\naha152x: %s\n", setup_str );
          printk("aha152x: usage: aha152x=<PORTBASE>,<IRQ>,<SCSI ID>,<RECONNECT>\n");
          panic("aha152x panics in line %d", __LINE__);
        }

      port_base       = setup_portbase;
      interrupt_level = setup_irq;
      this_host       = setup_scsiid;
      can_disconnect  = setup_reconnect;

      for( i=0; i<PORT_COUNT && (port_base != ports[i]); i++)
        ;

      if(i==PORT_COUNT)
        {
          printk("unknown portbase 0x%03x\n", port_base);
          panic("aha152x panics in line %d", __LINE__);
        }

      if(!aha152x_porttest(port_base))
        {
          printk("portbase 0x%03x fails probe\n", port_base);
          panic("aha152x panics in line %d", __LINE__);
        }

      i=0;
      while(ints[i] && (interrupt_level!=ints[i]))
        i++;
      if(!ints[i])
        {
          printk("illegal IRQ %d\n", interrupt_level);
          panic("aha152x panics in line %d", __LINE__);
        }

      if( (this_host < 0) || (this_host > 7) )
        {
          printk("illegal SCSI ID %d\n", this_host);
          panic("aha152x panics in line %d", __LINE__);
        }

      if( (can_disconnect < 0) || (can_disconnect > 1) )
        {
          printk("reconnect %d should be 0 or 1\n", can_disconnect);
          panic("aha152x panics in line %d", __LINE__);
        }
      printk("ok, ");
    }
  else
    {
#if !defined(SKIP_BIOSTEST)
      printk("BIOS test: ");
      ok=0;
      for( i=0; i < ADDRESS_COUNT && !ok; i++)
        for( j=0; (j < SIGNATURE_COUNT) && !ok; j++)
          ok=!memcmp((void *) addresses[i]+signatures[j].sig_offset,
                     (void *) signatures[j].signature,
                     (int) signatures[j].sig_length);

      if(!ok)
        {
#if defined(DEBUG_RACE)
          leave_driver("(1) detect");
#endif
          printk("failed\n");
          return 0;
        }
      printk("ok, ");
#endif /* !SKIP_BIOSTEST */
 
#if !defined(PORTBASE)
      printk("porttest: ");
      for( i=0; i<PORT_COUNT && !aha152x_porttest(ports[i]); i++)
        ;

      if(i==PORT_COUNT)
        {
          printk("failed\n");
#if defined(DEBUG_RACE)
          leave_driver("(2) detect");
#endif
          return 0;
        }
      else
        port_base=ports[i];
      printk("ok, ");
#else
      port_base=PORTBASE;
#endif /* !PORTBASE */

#if defined(AUTOCONF)

      conf.cf_port = (GETPORT(PORTA)<<8) + GETPORT(PORTB);

      interrupt_level = ints[conf.cf_irq];
      this_host       = conf.cf_id;
      can_disconnect  = conf.cf_tardisc;

      printk("auto configuration: ok, ");

#endif /* AUTOCONF */

#if defined(IRQ)
      interrupt_level = IRQ; 
#endif

#if defined(SCSI_ID)
      this_host = SCSI_ID;
#endif

#if defined(RECONNECT)
      can_disconnect=RECONNECT;
#endif
    }

  printk("detection complete\n");
 
  sa.sa_handler  = aha152x_intr;
  sa.sa_flags    = SA_INTERRUPT;
  sa.sa_mask     = 0;
  sa.sa_restorer = NULL;
  
  ok = irqaction( interrupt_level, &sa);
  
  if(ok<0)
    {
      if(ok == -EINVAL)
        {
           printk("aha152x: bad IRQ %d.\n", interrupt_level);
           printk("         Contact author.\n");
        }
      else
        if( ok == -EBUSY)
          printk( "aha152x: IRQ %d already in use. Configure another.\n",
                  interrupt_level);
        else
          {
            printk( "\naha152x: Unexpected error code on requesting IRQ %d.\n",
                    interrupt_level);
            printk("         Contact author.\n");
          }
      panic("aha152x: driver needs an IRQ.\n");
    }

  SETPORT( SCSIID, this_host << 4 );
  scsi_hosts[hostno].this_id=this_host;
  
  if(can_disconnect)
    scsi_hosts[hostno].can_queue=AHA152X_MAXQUEUE;

  /* RESET OUT */
  SETBITS(SCSISEQ, SCSIRSTO );
  do_pause(5);
  CLRBITS(SCSISEQ, SCSIRSTO );
  do_pause(10);

  aha152x_reset(NULL);

  printk("aha152x: vital data: PORTBASE=0x%03x, IRQ=%d, SCSI ID=%d, reconnect=%s, parity=enabled\n",
         port_base, interrupt_level, this_host, can_disconnect ? "enabled" : "disabled" );

  snarf_region(port_base, TEST-SCSISEQ);        /* Register */
  
  /* not expecting any interrupts */
  SETPORT(SIMODE0, 0);
  SETPORT(SIMODE1, 0);

#if defined(DEBUG_RACE)
  leave_driver("(3) detect");
#endif

  SETBITS( DMACNTRL0, INTEN);
  return 1;
}

/*
 *  return the name of the thing
 */
const char *aha152x_info(void)
{
#if defined(DEBUG_RACE)
  enter_driver("info");
  leave_driver("info");
#else
#if defined(DEBUG_INFO)
  printk("\naha152x: info()\n");
#endif
#endif
  return(aha152x_id);
}

/* 
 *  Queue a command and setup interrupts for a free bus.
 */
int aha152x_queue( Scsi_Cmnd * SCpnt, void (*done)(Scsi_Cmnd *))
{
#if defined(DEBUG_RACE)
  enter_driver("queue");
#else
#if defined(DEBUG_QUEUE)
  printk("aha152x: queue(), ");
#endif
#endif


#if defined(DEBUG_QUEUE)
  printk( "SCpnt (target = %d lun = %d cmnd = 0x%02x pieces = %d size = %u), ",
          SCpnt->target,
          SCpnt->lun,
          *(unsigned char *)SCpnt->cmnd,
          SCpnt->use_sg,
          SCpnt->request_bufflen );
  disp_ports();
#endif

  SCpnt->scsi_done =       done;

  /* setup scratch area
     SCp.ptr              : buffer pointer
     SCp.this_residual    : buffer length
     SCp.buffer           : next buffer
     SCp.buffers_residual : left buffers in list
     SCp.phase            : current state of the command */
  SCpnt->SCp.phase = not_issued;
  if (SCpnt->use_sg)
    {
      SCpnt->SCp.buffer           = (struct scatterlist *)SCpnt->request_buffer;
      SCpnt->SCp.ptr              = SCpnt->SCp.buffer->address;
      SCpnt->SCp.this_residual    = SCpnt->SCp.buffer->length;
      SCpnt->SCp.buffers_residual = SCpnt->use_sg - 1;
    }
  else
    {
      SCpnt->SCp.ptr              = (char *)SCpnt->request_buffer;
      SCpnt->SCp.this_residual    = SCpnt->request_bufflen;
      SCpnt->SCp.buffer           = NULL;
      SCpnt->SCp.buffers_residual = 0;
    }
          
  SCpnt->SCp.Status              = CHECK_CONDITION;
  SCpnt->SCp.Message             = 0;
  SCpnt->SCp.have_data_in        = 0;
  SCpnt->SCp.sent_command        = 0;

  /* Turn led on, when this is the first command. */
  cli();
  commands++;
  if(commands==1)
    SETPORT( PORTA, 1 );

#if defined(DEBUG_QUEUES)
  printk("i+ (%d), ", commands );
#endif
  append_SC( &issue_SC, SCpnt);
  
  /* Enable bus free interrupt, when we aren't currently on the bus */
  if(!current_SC)
    {
      SETPORT(SIMODE0, disconnected_SC ? ENSELDI : 0 );
      SETPORT(SIMODE1, issue_SC ? ENBUSFREE : 0);
    }
  sti();

  return 0;
}

/*
 *  We only support command in interrupt-driven fashion
 */
int aha152x_command( Scsi_Cmnd *SCpnt )
{
  printk( "aha152x: interrupt driven driver; use aha152x_queue()\n" );
  return -1;
}

/*
 *  Abort a queued command
 *  (commands that are on the bus can't be aborted easily)
 */
int aha152x_abort( Scsi_Cmnd *SCpnt, int code )
{
  Scsi_Cmnd *ptr, *prev;

  cli();

#if defined(DEBUG_ABORT)
  printk("aha152x: abort(), SCpnt=0x%08x, ", (unsigned long) SCpnt );
#endif

  show_queues();

  /* look for command in issue queue */
  for( ptr=issue_SC, prev=NULL;
       ptr && ptr!=SCpnt;
       prev=ptr, ptr=(Scsi_Cmnd *) ptr->host_scribble)
    ;

  if(ptr)
    {
      /* dequeue */
      if(prev)
        prev->host_scribble = ptr->host_scribble;
      else
        issue_SC = (Scsi_Cmnd *) ptr->host_scribble;
      sti();

      ptr->host_scribble = NULL;
      ptr->result = (code ? code : DID_ABORT ) << 16;
      ptr->done(ptr);
      return 0;
    }

  /* Fail abortion, if we're on the bus */
  if (current_SC)
    {
       sti();
       return -1;
    }

  /* look for command in disconnected queue */
  for( ptr=disconnected_SC, prev=NULL;
       ptr && ptr!=SCpnt;
       prev=ptr, ptr=(Scsi_Cmnd *) ptr->host_scribble)
    ;

  if(ptr && TESTLO(SSTAT1, BUSFREE) )
    printk("bus busy but no current command, ");

  if(ptr && TESTHI(SSTAT1, BUSFREE) )
    {
      /* dequeue */
      if(prev)
        prev->host_scribble = ptr->host_scribble;
      else
        issue_SC = (Scsi_Cmnd *) ptr->host_scribble;

      /* set command current and initiate selection,
         let the interrupt routine take care of the abortion */
      current_SC     = ptr;
      ptr->SCp.phase = in_selection|aborted;
      SETPORT( SCSIID, (this_host << OID_) | current_SC->target );

      /* enable interrupts for SELECTION OUT DONE and SELECTION TIME OUT */
      SETPORT( SIMODE0, ENSELDO | (disconnected_SC ? ENSELDI : 0) );
      SETPORT( SIMODE1, ENSELTIMO );

      /* Enable SELECTION OUT sequence */
      SETBITS(SCSISEQ, ENSELO | ENAUTOATNO );

      SETBITS( DMACNTRL0, INTEN );
      abort_result=0;
      sti();

      /* sleep until the abortion is complete */
      sleep_on( &abortion_complete );
      return abort_result;
    }
  else
    printk("aha152x: bus busy but no current command\n");

  /* command wasn't found */
  sti();
  return 0;
}

/*
 *  Restore default values to the AIC-6260 registers and reset the fifos
 */
static void aha152x_reset_ports(void)
{
  /* disable interrupts */
  SETPORT(DMACNTRL0, RSTFIFO);

  SETPORT(SCSISEQ, 0);

  SETPORT(SXFRCTL1, 0);
  SETPORT( SCSISIG, 0);
  SETPORT(SCSIRATE, 0);

  /* clear all interrupt conditions */
  SETPORT(SSTAT0, 0x7f);
  SETPORT(SSTAT1, 0xef);

  SETPORT(SSTAT4, SYNCERR|FWERR|FRERR);

  SETPORT(DMACNTRL0, 0);
  SETPORT(DMACNTRL1, 0);

  SETPORT(BRSTCNTRL, 0xf1);

  /* clear SCSI fifo and transfer count */
  SETPORT(SXFRCTL0, CH1|CLRCH1|CLRSTCNT);
  SETPORT(SXFRCTL0, CH1);

  /* enable interrupts */
  SETPORT(SIMODE0, disconnected_SC ? ENSELDI : 0 );
  SETPORT(SIMODE1, issue_SC ? ENBUSFREE : 0);
}

/*
 *  Reset registers, reset a hanging bus and
 *  kill active and disconnected commands
 */
int aha152x_reset(Scsi_Cmnd * __unused)
{
  Scsi_Cmnd *ptr;

  aha152x_reset_ports();

  /* Reset, if bus hangs */
  if( TESTLO( SSTAT1, BUSFREE ) )
    {
       CLRBITS( DMACNTRL0, INTEN );

#if defined( DEBUG_RESET )
       printk("aha152x: reset(), bus not free: SCSI RESET OUT\n");
#endif

       show_queues();

       if(current_SC)
         {
           current_SC->host_scribble = NULL;
           current_SC->result = DID_RESET << 16;
           current_SC->done(current_SC);
           current_SC=NULL;
         }