#define AUTOSENSE
  #define PSEUDO_DMA
  #define DONT_USE_INTR
  #define UNSAFE			/* Leave interrupts enabled during pseudo-dma I/O */
  #define xNDEBUG (NDEBUG_INTR+NDEBUG_RESELECTION+\
  		 NDEBUG_SELECTION+NDEBUG_ARBITRATION)
  #define DMA_WORKS_RIGHT
  
  
  /*
   * DTC 3180/3280 driver, by
   *	Ray Van Tassle	rayvt@comm.mot.com
   *
   *	taken from ...
   *	Trantor T128/T128F/T228 driver by...
   *
   * 	Drew Eckhardt
   *	Visionary Computing
   *	(Unix and Linux consulting and custom programming)
   *	drew@colorado.edu
   *      +1 (303) 440-4894
   *
   * DISTRIBUTION RELEASE 1.
   *
   * For more information, please consult 
   *
   * NCR 5380 Family
   * SCSI Protocol Controller
   * Databook
  */
  
  /*
   * Options : 
   * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
   *      for commands that return with a CHECK CONDITION status. 
   *
   * PSEUDO_DMA - enables PSEUDO-DMA hardware, should give a 3-4X performance
   * increase compared to polled I/O.
   *
   * PARITY - enable parity checking.  Not supported.
   *
   * UNSAFE - leave interrupts enabled during pseudo-DMA transfers. 
   *		You probably want this.
   *
   * The card is detected and initialized in one of several ways : 
   * 1.  Autoprobe (default) - since the board is memory mapped, 
   *     a BIOS signature is scanned for to locate the registers.
   *     An interrupt is triggered to autoprobe for the interrupt
   *     line.
   *
   * 2.  With command line overrides - dtc=address,irq may be 
   *     used on the LILO command line to override the defaults.
   * 
  */
  
  /*----------------------------------------------------------------*/
  /* the following will set the monitor border color (useful to find
   where something crashed or gets stuck at */
  /* 1 = blue
   2 = green
   3 = cyan
   4 = red
   5 = magenta
   6 = yellow
   7 = white
  */
  #if 0
  #define rtrc(i) {inb(0x3da); outb(0x31, 0x3c0); outb((i), 0x3c0);}
  #else
  #define rtrc(i) {}
  #endif
  
  
  #include <linux/module.h>
  #include <linux/signal.h>
  #include <linux/blkdev.h>
  #include <linux/delay.h>
  #include <linux/stat.h>
  #include <linux/string.h>
  #include <linux/init.h>
  #include <linux/interrupt.h>
  #include <linux/io.h>
  #include "scsi.h"
  #include <scsi/scsi_host.h>
  #include "dtc.h"
  #define AUTOPROBE_IRQ
  #include "NCR5380.h"
  
  
  #define DTC_PUBLIC_RELEASE 2
  
  /*
   * The DTC3180 & 3280 boards are memory mapped.
   * 
   */
  
  /*
   */
  /* Offset from DTC_5380_OFFSET */
  #define DTC_CONTROL_REG		0x100	/* rw */
  #define D_CR_ACCESS		0x80	/* ro set=can access 3280 registers */
  #define CSR_DIR_READ		0x40	/* rw direction, 1 = read 0 = write */
  
  #define CSR_RESET              0x80	/* wo  Resets 53c400 */
  #define CSR_5380_REG           0x80	/* ro  5380 registers can be accessed */
  #define CSR_TRANS_DIR          0x40	/* rw  Data transfer direction */
  #define CSR_SCSI_BUFF_INTR     0x20	/* rw  Enable int on transfer ready */
  #define CSR_5380_INTR          0x10	/* rw  Enable 5380 interrupts */
  #define CSR_SHARED_INTR        0x08	/* rw  Interrupt sharing */
  #define CSR_HOST_BUF_NOT_RDY   0x04	/* ro  Host buffer not ready */
  #define CSR_SCSI_BUF_RDY       0x02	/* ro  SCSI buffer ready */
  #define CSR_GATED_5380_IRQ     0x01	/* ro  Last block xferred */
  #define CSR_INT_BASE (CSR_SCSI_BUFF_INTR | CSR_5380_INTR)
  
  
  #define DTC_BLK_CNT		0x101	/* rw 
  					 * # of 128-byte blocks to transfer */
  
  
  #define D_CR_ACCESS             0x80	/* ro set=can access 3280 registers */
  
  #define DTC_SWITCH_REG		0x3982	/* ro - DIP switches */
  #define DTC_RESUME_XFER		0x3982	/* wo - resume data xfer 
  					 * after disconnect/reconnect*/
  
  #define DTC_5380_OFFSET		0x3880	/* 8 registers here, see NCR5380.h */
  
  /*!!!! for dtc, it's a 128 byte buffer at 3900 !!! */
  #define DTC_DATA_BUF		0x3900	/* rw 128 bytes long */
  
  static struct override {
  	unsigned int address;
  	int irq;
  } overrides
  #ifdef OVERRIDE
  [] __initdata = OVERRIDE;
  #else
  [4] __initdata = {
  	{ 0, IRQ_AUTO }, { 0, IRQ_AUTO }, { 0, IRQ_AUTO }, { 0, IRQ_AUTO }
  };
  #endif
  
  #define NO_OVERRIDES ARRAY_SIZE(overrides)
  
  static struct base {
  	unsigned long address;
  	int noauto;
  } bases[] __initdata = {
  	{ 0xcc000, 0 },
  	{ 0xc8000, 0 },
  	{ 0xdc000, 0 },
  	{ 0xd8000, 0 }
  };
  
  #define NO_BASES ARRAY_SIZE(bases)
  
  static const struct signature {
  	const char *string;
  	int offset;
  } signatures[] = {
  	{"DATA TECHNOLOGY CORPORATION BIOS", 0x25},
  };
  
  #define NO_SIGNATURES ARRAY_SIZE(signatures)
  
  #ifndef MODULE
  /*
   * Function : dtc_setup(char *str, int *ints)
   *
   * Purpose : LILO command line initialization of the overrides array,
   *
   * Inputs : str - unused, ints - array of integer parameters with ints[0]
   *	equal to the number of ints.
   *
   */
  
  static void __init dtc_setup(char *str, int *ints)
  {
  	static int commandline_current = 0;
  	int i;
  	if (ints[0] != 2)
  		printk("dtc_setup: usage dtc=address,irq
  ");
  	else if (commandline_current < NO_OVERRIDES) {
  		overrides[commandline_current].address = ints[1];
  		overrides[commandline_current].irq = ints[2];
  		for (i = 0; i < NO_BASES; ++i)
  			if (bases[i].address == ints[1]) {
  				bases[i].noauto = 1;
  				break;
  			}
  		++commandline_current;
  	}
  }
  #endif
  
  /* 
   * Function : int dtc_detect(struct scsi_host_template * tpnt)
   *
   * Purpose : detects and initializes DTC 3180/3280 controllers
   *	that were autoprobed, overridden on the LILO command line, 
   *	or specified at compile time.
   *
   * Inputs : tpnt - template for this SCSI adapter.
   * 
   * Returns : 1 if a host adapter was found, 0 if not.
   *
  */
  
  static int __init dtc_detect(struct scsi_host_template * tpnt)
  {
  	static int current_override = 0, current_base = 0;
  	struct Scsi_Host *instance;
  	unsigned int addr;
  	void __iomem *base;
  	int sig, count;
  
  	tpnt->proc_name = "dtc3x80";
  	tpnt->show_info = dtc_show_info;
  	tpnt->write_info = dtc_write_info;
  
  	for (count = 0; current_override < NO_OVERRIDES; ++current_override) {
  		addr = 0;
  		base = NULL;
  
  		if (overrides[current_override].address) {
  			addr = overrides[current_override].address;
  			base = ioremap(addr, 0x2000);
  			if (!base)
  				addr = 0;
  		} else
  			for (; !addr && (current_base < NO_BASES); ++current_base) {
  #if (DTCDEBUG & DTCDEBUG_INIT)
  				printk(KERN_DEBUG "scsi-dtc : probing address %08x
  ", bases[current_base].address);
  #endif
  				if (bases[current_base].noauto)
  					continue;
  				base = ioremap(bases[current_base].address, 0x2000);
  				if (!base)
  					continue;
  				for (sig = 0; sig < NO_SIGNATURES; ++sig) {
  					if (check_signature(base + signatures[sig].offset, signatures[sig].string, strlen(signatures[sig].string))) {
  						addr = bases[current_base].address;
  #if (DTCDEBUG & DTCDEBUG_INIT)
  						printk(KERN_DEBUG "scsi-dtc : detected board.
  ");
  #endif
  						goto found;
  					}
  				}
  				iounmap(base);
  			}
  
  #if defined(DTCDEBUG) && (DTCDEBUG & DTCDEBUG_INIT)
  		printk(KERN_DEBUG "scsi-dtc : base = %08x
  ", addr);
  #endif
  
  		if (!addr)
  			break;
  
  found:
  		instance = scsi_register(tpnt, sizeof(struct NCR5380_hostdata));
  		if (instance == NULL)
  			break;
  
  		instance->base = addr;
  		((struct NCR5380_hostdata *)(instance)->hostdata)->base = base;
  
  		NCR5380_init(instance, 0);
  
  		NCR5380_write(DTC_CONTROL_REG, CSR_5380_INTR);	/* Enable int's */
  		if (overrides[current_override].irq != IRQ_AUTO)
  			instance->irq = overrides[current_override].irq;
  		else
  			instance->irq = NCR5380_probe_irq(instance, DTC_IRQS);
  
  #ifndef DONT_USE_INTR
  		/* With interrupts enabled, it will sometimes hang when doing heavy
  		 * reads. So better not enable them until I finger it out. */
  		if (instance->irq != SCSI_IRQ_NONE)
  			if (request_irq(instance->irq, dtc_intr, IRQF_DISABLED,
  					"dtc", instance)) {
  				printk(KERN_ERR "scsi%d : IRQ%d not free, interrupts disabled
  ", instance->host_no, instance->irq);
  				instance->irq = SCSI_IRQ_NONE;
  			}
  
  		if (instance->irq == SCSI_IRQ_NONE) {
  			printk(KERN_WARNING "scsi%d : interrupts not enabled. for better interactive performance,
  ", instance->host_no);
  			printk(KERN_WARNING "scsi%d : please jumper the board for a free IRQ.
  ", instance->host_no);
  		}
  #else
  		if (instance->irq != SCSI_IRQ_NONE)
  			printk(KERN_WARNING "scsi%d : interrupts not used. Might as well not jumper it.
  ", instance->host_no);
  		instance->irq = SCSI_IRQ_NONE;
  #endif
  #if defined(DTCDEBUG) && (DTCDEBUG & DTCDEBUG_INIT)
  		printk("scsi%d : irq = %d
  ", instance->host_no, instance->irq);
  #endif
  
  		printk(KERN_INFO "scsi%d : at 0x%05X", instance->host_no, (int) instance->base);
  		if (instance->irq == SCSI_IRQ_NONE)
  			printk(" interrupts disabled");
  		else
  			printk(" irq %d", instance->irq);
  		printk(" options CAN_QUEUE=%d  CMD_PER_LUN=%d release=%d", CAN_QUEUE, CMD_PER_LUN, DTC_PUBLIC_RELEASE);
  		NCR5380_print_options(instance);
  		printk("
  ");
  
  		++current_override;
  		++count;
  	}
  	return count;
  }
  
  /*
   * Function : int dtc_biosparam(Disk * disk, struct block_device *dev, int *ip)
   *
   * Purpose : Generates a BIOS / DOS compatible H-C-S mapping for 
   *	the specified device / size.
   * 
   * Inputs : size = size of device in sectors (512 bytes), dev = block device
   *	major / minor, ip[] = {heads, sectors, cylinders}  
   *
   * Returns : always 0 (success), initializes ip
   *	
  */
  
  /* 
   * XXX Most SCSI boards use this mapping, I could be incorrect.  Some one
   * using hard disks on a trantor should verify that this mapping corresponds
   * to that used by the BIOS / ASPI driver by running the linux fdisk program
   * and matching the H_C_S coordinates to what DOS uses.
  */
  
  static int dtc_biosparam(struct scsi_device *sdev, struct block_device *dev,
  			 sector_t capacity, int *ip)
  {
  	int size = capacity;
  
  	ip[0] = 64;
  	ip[1] = 32;
  	ip[2] = size >> 11;
  	return 0;
  }
  
  
  /****************************************************************
   * Function : int NCR5380_pread (struct Scsi_Host *instance, 
   *	unsigned char *dst, int len)
   *
   * Purpose : Fast 5380 pseudo-dma read function, reads len bytes to 
   *	dst
   * 
   * Inputs : dst = destination, len = length in bytes
   *
   * Returns : 0 on success, non zero on a failure such as a watchdog 
   * 	timeout.
  */
  
  static int dtc_maxi = 0;
  static int dtc_wmaxi = 0;
  
  static inline int NCR5380_pread(struct Scsi_Host *instance, unsigned char *dst, int len)
  {
  	unsigned char *d = dst;
  	int i;			/* For counting time spent in the poll-loop */
  	NCR5380_local_declare();
  	NCR5380_setup(instance);
  
  	i = 0;
  	NCR5380_read(RESET_PARITY_INTERRUPT_REG);
  	NCR5380_write(MODE_REG, MR_ENABLE_EOP_INTR | MR_DMA_MODE);
  	if (instance->irq == SCSI_IRQ_NONE)
  		NCR5380_write(DTC_CONTROL_REG, CSR_DIR_READ);
  	else
  		NCR5380_write(DTC_CONTROL_REG, CSR_DIR_READ | CSR_INT_BASE);
  	NCR5380_write(DTC_BLK_CNT, len >> 7);	/* Block count */
  	rtrc(1);
  	while (len > 0) {
  		rtrc(2);
  		while (NCR5380_read(DTC_CONTROL_REG) & CSR_HOST_BUF_NOT_RDY)
  			++i;
  		rtrc(3);
  		memcpy_fromio(d, base + DTC_DATA_BUF, 128);
  		d += 128;
  		len -= 128;
  		rtrc(7);
  		/*** with int's on, it sometimes hangs after here.
  		 * Looks like something makes HBNR go away. */
  	}
  	rtrc(4);
  	while (!(NCR5380_read(DTC_CONTROL_REG) & D_CR_ACCESS))
  		++i;
  	NCR5380_write(MODE_REG, 0);	/* Clear the operating mode */
  	rtrc(0);
  	NCR5380_read(RESET_PARITY_INTERRUPT_REG);
  	if (i > dtc_maxi)
  		dtc_maxi = i;
  	return (0);
  }
  
  /****************************************************************
   * Function : int NCR5380_pwrite (struct Scsi_Host *instance, 
   *	unsigned char *src, int len)
   *
   * Purpose : Fast 5380 pseudo-dma write function, transfers len bytes from
   *	src
   * 
   * Inputs : src = source, len = length in bytes
   *
   * Returns : 0 on success, non zero on a failure such as a watchdog 
   * 	timeout.
  */
  
  static inline int NCR5380_pwrite(struct Scsi_Host *instance, unsigned char *src, int len)
  {
  	int i;
  	NCR5380_local_declare();
  	NCR5380_setup(instance);
  
  	NCR5380_read(RESET_PARITY_INTERRUPT_REG);
  	NCR5380_write(MODE_REG, MR_ENABLE_EOP_INTR | MR_DMA_MODE);
  	/* set direction (write) */
  	if (instance->irq == SCSI_IRQ_NONE)
  		NCR5380_write(DTC_CONTROL_REG, 0);
  	else
  		NCR5380_write(DTC_CONTROL_REG, CSR_5380_INTR);
  	NCR5380_write(DTC_BLK_CNT, len >> 7);	/* Block count */
  	for (i = 0; len > 0; ++i) {
  		rtrc(5);
  		/* Poll until the host buffer can accept data. */
  		while (NCR5380_read(DTC_CONTROL_REG) & CSR_HOST_BUF_NOT_RDY)
  			++i;
  		rtrc(3);
  		memcpy_toio(base + DTC_DATA_BUF, src, 128);
  		src += 128;
  		len -= 128;
  	}
  	rtrc(4);
  	while (!(NCR5380_read(DTC_CONTROL_REG) & D_CR_ACCESS))
  		++i;
  	rtrc(6);
  	/* Wait until the last byte has been sent to the disk */
  	while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT))
  		++i;
  	rtrc(7);
  	/* Check for parity error here. fixme. */
  	NCR5380_write(MODE_REG, 0);	/* Clear the operating mode */
  	rtrc(0);
  	if (i > dtc_wmaxi)
  		dtc_wmaxi = i;
  	return (0);
  }
  
  MODULE_LICENSE("GPL");
  
  #include "NCR5380.c"
  
  static int dtc_release(struct Scsi_Host *shost)
  {
  	NCR5380_local_declare();
  	NCR5380_setup(shost);
  	if (shost->irq)
  		free_irq(shost->irq, shost);
  	NCR5380_exit(shost);
  	if (shost->io_port && shost->n_io_port)
  		release_region(shost->io_port, shost->n_io_port);
  	scsi_unregister(shost);
  	iounmap(base);
  	return 0;
  }
  
  static struct scsi_host_template driver_template = {
  	.name				= "DTC 3180/3280 ",
  	.detect				= dtc_detect,
  	.release			= dtc_release,
  	.queuecommand			= dtc_queue_command,
  	.eh_abort_handler		= dtc_abort,
  	.eh_bus_reset_handler		= dtc_bus_reset,
  	.bios_param     		= dtc_biosparam,
  	.can_queue      		= CAN_QUEUE,
  	.this_id        		= 7,
  	.sg_tablesize   		= SG_ALL,
  	.cmd_per_lun    		= CMD_PER_LUN,
  	.use_clustering 		= DISABLE_CLUSTERING,
  };
  #include "scsi_module.c"