drivers/scsi/dtc.c - kernel/msm-4.9 - Gitiles


 #define PSEUDO_DMA
 #define DONT_USE_INTR
 #define UNSAFE			/* Leave interrupts enabled during pseudo-dma I/O */
 #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
  */

 /*
  * 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/scsi_host.h>
 #include "dtc.h"
 #define AUTOPROBE_IRQ
 #include "NCR5380.h"

 /*
  * 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 int __init dtc_setup(char *str)
 {
 	static int commandline_current = 0;
 	int i;
 	int ints[10];

 	get_options(str, ARRAY_SIZE(ints), ints);
 	if (ints[0] != 2)
 		printk("dtc_setup: usage dtc=address,irq\n");
 	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;
 	}
 	return 1;
 }

 __setup("dtc=", dtc_setup);
 #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;

 	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\n", 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.\n");
 #endif
 						goto found;
 					}
 				}
 				iounmap(base);
 			}

 #if defined(DTCDEBUG) && (DTCDEBUG & DTCDEBUG_INIT)
 		printk(KERN_DEBUG "scsi-dtc : base = %08x\n", 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);

 		/* Compatibility with documented NCR5380 kernel parameters */
 		if (instance->irq == 255)
 			instance->irq = NO_IRQ;

 #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 != NO_IRQ)
 			if (request_irq(instance->irq, dtc_intr, 0,
 					"dtc", instance)) {
 				printk(KERN_ERR "scsi%d : IRQ%d not free, interrupts disabled\n", instance->host_no, instance->irq);
 				instance->irq = NO_IRQ;
 			}

 		if (instance->irq == NO_IRQ) {
 			printk(KERN_WARNING "scsi%d : interrupts not enabled. for better interactive performance,\n", instance->host_no);
 			printk(KERN_WARNING "scsi%d : please jumper the board for a free IRQ.\n", instance->host_no);
 		}
 #else
 		if (instance->irq != NO_IRQ)
 			printk(KERN_WARNING "scsi%d : interrupts not used. Might as well not jumper it.\n", instance->host_no);
 		instance->irq = NO_IRQ;
 #endif
 #if defined(DTCDEBUG) && (DTCDEBUG & DTCDEBUG_INIT)
 		printk("scsi%d : irq = %d\n", instance->host_no, instance->irq);
 #endif

 		++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 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 */
 	struct NCR5380_hostdata *hostdata = shost_priv(instance);
 	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 == NO_IRQ)
 		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 > hostdata->spin_max_r)
 		hostdata->spin_max_r = 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;
 	struct NCR5380_hostdata *hostdata = shost_priv(instance);
 	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 == NO_IRQ)
 		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 > hostdata->spin_max_w)
 		hostdata->spin_max_w = 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 != NO_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,
 	.proc_name			= "dtc3x80",
 	.show_info			= dtc_show_info,
 	.write_info			= dtc_write_info,
 	.info				= dtc_info,
 	.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"

	#define PSEUDO_DMA
	#define DONT_USE_INTR
	#define UNSAFE /* Leave interrupts enabled during pseudo-dma I/O */
	#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
	*/

	/*
	* 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/scsi_host.h>
	#include "dtc.h"
	#define AUTOPROBE_IRQ
	#include "NCR5380.h"

	/*
	* 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 int __init dtc_setup(char *str)
	{
	static int commandline_current = 0;
	int i;
	int ints[10];

	get_options(str, ARRAY_SIZE(ints), ints);
	if (ints[0] != 2)
	printk("dtc_setup: usage dtc=address,irq\n");
	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;
	}
	return 1;
	}

	__setup("dtc=", dtc_setup);
	#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;

	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\n", 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.\n");
	#endif
	goto found;
	}
	}
	iounmap(base);
	}

	#if defined(DTCDEBUG) && (DTCDEBUG & DTCDEBUG_INIT)
	printk(KERN_DEBUG "scsi-dtc : base = %08x\n", 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);

	/* Compatibility with documented NCR5380 kernel parameters */
	if (instance->irq == 255)
	instance->irq = NO_IRQ;

	#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 != NO_IRQ)
	if (request_irq(instance->irq, dtc_intr, 0,
	"dtc", instance)) {
	printk(KERN_ERR "scsi%d : IRQ%d not free, interrupts disabled\n", instance->host_no, instance->irq);
	instance->irq = NO_IRQ;
	}

	if (instance->irq == NO_IRQ) {
	printk(KERN_WARNING "scsi%d : interrupts not enabled. for better interactive performance,\n", instance->host_no);
	printk(KERN_WARNING "scsi%d : please jumper the board for a free IRQ.\n", instance->host_no);
	}
	#else
	if (instance->irq != NO_IRQ)
	printk(KERN_WARNING "scsi%d : interrupts not used. Might as well not jumper it.\n", instance->host_no);
	instance->irq = NO_IRQ;
	#endif
	#if defined(DTCDEBUG) && (DTCDEBUG & DTCDEBUG_INIT)
	printk("scsi%d : irq = %d\n", instance->host_no, instance->irq);
	#endif

	++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 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 */
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	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 == NO_IRQ)
	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 > hostdata->spin_max_r)
	hostdata->spin_max_r = 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;
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	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 == NO_IRQ)
	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 > hostdata->spin_max_w)
	hostdata->spin_max_w = 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 != NO_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,
	.proc_name = "dtc3x80",
	.show_info = dtc_show_info,
	.write_info = dtc_write_info,
	.info = dtc_info,
	.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"