drivers/scsi/53c700.h - linux-imx - Git at Google

 /* -*- mode: c; c-basic-offset: 8 -*- */

 /* Driver for 53c700 and 53c700-66 chips from NCR and Symbios
  *
  * Copyright (C) 2001 by James.Bottomley@HansenPartnership.com
  */

 #ifndef _53C700_H
 #define _53C700_H

 #include <linux/interrupt.h>
 #include <asm/io.h>

 #include <scsi/scsi_device.h>
 #include <scsi/scsi_cmnd.h>

 /* Turn on for general debugging---too verbose for normal use */
 #undef	NCR_700_DEBUG
 /* Debug the tag queues, checking hash queue allocation and deallocation
  * and search for duplicate tags */
 #undef NCR_700_TAG_DEBUG

 #ifdef NCR_700_DEBUG
 #define DEBUG(x)	printk x
 #define DDEBUG(prefix, sdev, fmt, a...) \
 	sdev_printk(prefix, sdev, fmt, ##a)
 #define CDEBUG(prefix, scmd, fmt, a...) \
 	scmd_printk(prefix, scmd, fmt, ##a)
 #else
 #define DEBUG(x)	do {} while (0)
 #define DDEBUG(prefix, scmd, fmt, a...) do {} while (0)
 #define CDEBUG(prefix, scmd, fmt, a...) do {} while (0)
 #endif

 /* The number of available command slots */
 #define NCR_700_COMMAND_SLOTS_PER_HOST	64
 /* The maximum number of Scatter Gathers we allow */
 #define NCR_700_SG_SEGMENTS		32
 /* The maximum number of luns (make this of the form 2^n) */
 #define NCR_700_MAX_LUNS		32
 #define NCR_700_LUN_MASK		(NCR_700_MAX_LUNS - 1)
 /* Maximum number of tags the driver ever allows per device */
 #define NCR_700_MAX_TAGS		16
 /* Tag depth the driver starts out with (can be altered in sysfs) */
 #define NCR_700_DEFAULT_TAGS		4
 /* This is the default number of commands per LUN in the untagged case.
  * two is a good value because it means we can have one command active and
  * one command fully prepared and waiting
  */
 #define NCR_700_CMD_PER_LUN		2
 /* magic byte identifying an internally generated REQUEST_SENSE command */
 #define NCR_700_INTERNAL_SENSE_MAGIC	0x42

 struct NCR_700_Host_Parameters;

 /* These are the externally used routines */
 struct Scsi_Host *NCR_700_detect(struct scsi_host_template *,
 		struct NCR_700_Host_Parameters *, struct device *);
 int NCR_700_release(struct Scsi_Host *host);
 irqreturn_t NCR_700_intr(int, void *);


 enum NCR_700_Host_State {
 	NCR_700_HOST_BUSY,
 	NCR_700_HOST_FREE,
 };

 struct NCR_700_SG_List {
 	/* The following is a script fragment to move the buffer onto the
 	 * bus and then link the next fragment or return */
 	#define	SCRIPT_MOVE_DATA_IN		0x09000000
 	#define	SCRIPT_MOVE_DATA_OUT		0x08000000
 	__u32	ins;
 	__u32	pAddr;
 	#define	SCRIPT_NOP			0x80000000
 	#define	SCRIPT_RETURN			0x90080000
 };

 struct NCR_700_Device_Parameters {
 	/* space for creating a request sense command. Really, except
 	 * for the annoying SCSI-2 requirement for LUN information in
 	 * cmnd[1], this could be in static storage */
 	unsigned char cmnd[MAX_COMMAND_SIZE];
 	__u8	depth;
 	struct scsi_cmnd *current_cmnd;	/* currently active command */
 };


 /* The SYNC negotiation sequence looks like:
  *
  * If DEV_NEGOTIATED_SYNC not set, tack and SDTR message on to the
  * initial identify for the device and set DEV_BEGIN_SYNC_NEGOTATION
  * If we get an SDTR reply, work out the SXFER parameters, squirrel
  * them away here, clear DEV_BEGIN_SYNC_NEGOTIATION and set
  * DEV_NEGOTIATED_SYNC.  If we get a REJECT msg, squirrel
  *
  *
  * 0:7	SXFER_REG negotiated value for this device
  * 8:15 Current queue depth
  * 16	negotiated SYNC flag
  * 17 begin SYNC negotiation flag
  * 18 device supports tag queueing */
 #define NCR_700_DEV_NEGOTIATED_SYNC	(1<<16)
 #define NCR_700_DEV_BEGIN_SYNC_NEGOTIATION	(1<<17)
 #define NCR_700_DEV_PRINT_SYNC_NEGOTIATION (1<<19)

 static inline char *NCR_700_get_sense_cmnd(struct scsi_device *SDp)
 {
 	struct NCR_700_Device_Parameters *hostdata = SDp->hostdata;

 	return hostdata->cmnd;
 }

 static inline void
 NCR_700_set_depth(struct scsi_device *SDp, __u8 depth)
 {
 	struct NCR_700_Device_Parameters *hostdata = SDp->hostdata;

 	hostdata->depth = depth;
 }
 static inline __u8
 NCR_700_get_depth(struct scsi_device *SDp)
 {
 	struct NCR_700_Device_Parameters *hostdata = SDp->hostdata;

 	return hostdata->depth;
 }
 static inline int
 NCR_700_is_flag_set(struct scsi_device *SDp, __u32 flag)
 {
 	return (spi_flags(SDp->sdev_target) & flag) == flag;
 }
 static inline int
 NCR_700_is_flag_clear(struct scsi_device *SDp, __u32 flag)
 {
 	return (spi_flags(SDp->sdev_target) & flag) == 0;
 }
 static inline void
 NCR_700_set_flag(struct scsi_device *SDp, __u32 flag)
 {
 	spi_flags(SDp->sdev_target) |= flag;
 }
 static inline void
 NCR_700_clear_flag(struct scsi_device *SDp, __u32 flag)
 {
 	spi_flags(SDp->sdev_target) &= ~flag;
 }

 enum NCR_700_tag_neg_state {
 	NCR_700_START_TAG_NEGOTIATION = 0,
 	NCR_700_DURING_TAG_NEGOTIATION = 1,
 	NCR_700_FINISHED_TAG_NEGOTIATION = 2,
 };

 static inline enum NCR_700_tag_neg_state
 NCR_700_get_tag_neg_state(struct scsi_device *SDp)
 {
 	return (enum NCR_700_tag_neg_state)((spi_flags(SDp->sdev_target)>>20) & 0x3);
 }

 static inline void
 NCR_700_set_tag_neg_state(struct scsi_device *SDp,
 			  enum NCR_700_tag_neg_state state)
 {
 	/* clear the slot */
 	spi_flags(SDp->sdev_target) &= ~(0x3 << 20);
 	spi_flags(SDp->sdev_target) |= ((__u32)state) << 20;
 }

 struct NCR_700_command_slot {
 	struct NCR_700_SG_List	SG[NCR_700_SG_SEGMENTS+1];
 	struct NCR_700_SG_List	*pSG;
 	#define NCR_700_SLOT_MASK 0xFC
 	#define NCR_700_SLOT_MAGIC 0xb8
 	#define	NCR_700_SLOT_FREE (0|NCR_700_SLOT_MAGIC) /* slot may be used */
 	#define NCR_700_SLOT_BUSY (1|NCR_700_SLOT_MAGIC) /* slot has command active on HA */
 	#define NCR_700_SLOT_QUEUED (2|NCR_700_SLOT_MAGIC) /* slot has command to be made active on HA */
 	__u8	state;
 	#define NCR_700_FLAG_AUTOSENSE	0x01
 	__u8	flags;
 	__u8	pad1[2];	/* Needed for m68k where min alignment is 2 bytes */
 	int	tag;
 	__u32	resume_offset;
 	struct scsi_cmnd *cmnd;
 	/* The pci_mapped address of the actual command in cmnd */
 	dma_addr_t	pCmd;
 	__u32		temp;
 	/* if this command is a pci_single mapping, holds the dma address
 	 * for later unmapping in the done routine */
 	dma_addr_t	dma_handle;
 	/* historical remnant, now used to link free commands */
 	struct NCR_700_command_slot *ITL_forw;
 };

 struct NCR_700_Host_Parameters {
 	/* These must be filled in by the calling driver */
 	int	clock;			/* board clock speed in MHz */
 	void __iomem	*base;		/* the base for the port (copied to host) */
 	struct device	*dev;
 	__u32	dmode_extra;	/* adjustable bus settings */
 	__u32	dcntl_extra;	/* adjustable bus settings */
 	__u32	ctest7_extra;	/* adjustable bus settings */
 	__u32	differential:1;	/* if we are differential */
 #ifdef CONFIG_53C700_LE_ON_BE
 	/* This option is for HP only.  Set it if your chip is wired for
 	 * little endian on this platform (which is big endian) */
 	__u32	force_le_on_be:1;
 #endif
 	__u32	chip710:1;	/* set if really a 710 not 700 */
 	__u32	burst_length:4;	/* set to 0 to disable 710 bursting */

 	/* NOTHING BELOW HERE NEEDS ALTERING */
 	__u32	fast:1;		/* if we can alter the SCSI bus clock
                                    speed (so can negiotiate sync) */
 	int	sync_clock;	/* The speed of the SYNC core */

 	__u32	*script;		/* pointer to script location */
 	__u32	pScript;		/* physical mem addr of script */

 	enum NCR_700_Host_State state; /* protected by state lock */
 	struct scsi_cmnd *cmd;
 	/* Note: pScript contains the single consistent block of
 	 * memory.  All the msgin, msgout and status are allocated in
 	 * this memory too (at separate cache lines).  TOTAL_MEM_SIZE
 	 * represents the total size of this area */
 #define	MSG_ARRAY_SIZE	8
 #define	MSGOUT_OFFSET	(L1_CACHE_ALIGN(sizeof(SCRIPT)))
 	__u8	*msgout;
 #define MSGIN_OFFSET	(MSGOUT_OFFSET + L1_CACHE_ALIGN(MSG_ARRAY_SIZE))
 	__u8	*msgin;
 #define STATUS_OFFSET	(MSGIN_OFFSET + L1_CACHE_ALIGN(MSG_ARRAY_SIZE))
 	__u8	*status;
 #define SLOTS_OFFSET	(STATUS_OFFSET + L1_CACHE_ALIGN(MSG_ARRAY_SIZE))
 	struct NCR_700_command_slot	*slots;
 #define	TOTAL_MEM_SIZE	(SLOTS_OFFSET + L1_CACHE_ALIGN(sizeof(struct NCR_700_command_slot) * NCR_700_COMMAND_SLOTS_PER_HOST))
 	int	saved_slot_position;
 	int	command_slot_count; /* protected by state lock */
 	__u8	tag_negotiated;
 	__u8	rev;
 	__u8	reselection_id;
 	__u8	min_period;

 	/* Free list, singly linked by ITL_forw elements */
 	struct NCR_700_command_slot *free_list;
 	/* Completion for waited for ops, like reset, abort or
 	 * device reset.
 	 *
 	 * NOTE: relies on single threading in the error handler to
 	 * have only one outstanding at once */
 	struct completion *eh_complete;
 };

 /*
  *	53C700 Register Interface - the offset from the Selected base
  *	I/O address */
 #ifdef CONFIG_53C700_LE_ON_BE
 #define bE	(hostdata->force_le_on_be ? 0 : 3)
 #define	bSWAP	(hostdata->force_le_on_be)
 #define bEBus	(!hostdata->force_le_on_be)
 #elif defined(__BIG_ENDIAN)
 #define bE	3
 #define bSWAP	0
 #elif defined(__LITTLE_ENDIAN)
 #define bE	0
 #define bSWAP	0
 #else
 #error "__BIG_ENDIAN or __LITTLE_ENDIAN must be defined, did you include byteorder.h?"
 #endif
 #ifndef bEBus
 #ifdef CONFIG_53C700_BE_BUS
 #define bEBus	1
 #else
 #define bEBus	0
 #endif
 #endif
 #define bS_to_cpu(x)	(bSWAP ? le32_to_cpu(x) : (x))
 #define bS_to_host(x)	(bSWAP ? cpu_to_le32(x) : (x))

 /* NOTE: These registers are in the LE register space only, the required byte
  * swapping is done by the NCR_700_{read|write}[b] functions */
 #define	SCNTL0_REG			0x00
 #define		FULL_ARBITRATION	0xc0
 #define 	PARITY			0x08
 #define		ENABLE_PARITY		0x04
 #define 	AUTO_ATN		0x02
 #define	SCNTL1_REG			0x01
 #define 	SLOW_BUS		0x80
 #define		ENABLE_SELECT		0x20
 #define		ASSERT_RST		0x08
 #define		ASSERT_EVEN_PARITY	0x04
 #define	SDID_REG			0x02
 #define	SIEN_REG			0x03
 #define 	PHASE_MM_INT		0x80
 #define 	FUNC_COMP_INT		0x40
 #define 	SEL_TIMEOUT_INT		0x20
 #define 	SELECT_INT		0x10
 #define 	GROSS_ERR_INT		0x08
 #define 	UX_DISC_INT		0x04
 #define 	RST_INT			0x02
 #define 	PAR_ERR_INT		0x01
 #define	SCID_REG			0x04
 #define SXFER_REG			0x05
 #define		ASYNC_OPERATION		0x00
 #define SODL_REG                        0x06
 #define	SOCL_REG			0x07
 #define	SFBR_REG			0x08
 #define	SIDL_REG			0x09
 #define	SBDL_REG			0x0A
 #define	SBCL_REG			0x0B
 /* read bits */
 #define		SBCL_IO			0x01
 /*write bits */
 #define		SYNC_DIV_AS_ASYNC	0x00
 #define		SYNC_DIV_1_0		0x01
 #define		SYNC_DIV_1_5		0x02
 #define		SYNC_DIV_2_0		0x03
 #define	DSTAT_REG			0x0C
 #define		ILGL_INST_DETECTED	0x01
 #define		WATCH_DOG_INTERRUPT	0x02
 #define		SCRIPT_INT_RECEIVED	0x04
 #define		ABORTED			0x10
 #define	SSTAT0_REG			0x0D
 #define		PARITY_ERROR		0x01
 #define		SCSI_RESET_DETECTED	0x02
 #define		UNEXPECTED_DISCONNECT	0x04
 #define		SCSI_GROSS_ERROR	0x08
 #define		SELECTED		0x10
 #define		SELECTION_TIMEOUT	0x20
 #define		FUNCTION_COMPLETE	0x40
 #define		PHASE_MISMATCH 		0x80
 #define	SSTAT1_REG			0x0E
 #define		SIDL_REG_FULL		0x80
 #define		SODR_REG_FULL		0x40
 #define		SODL_REG_FULL		0x20
 #define SSTAT2_REG                      0x0F
 #define CTEST0_REG                      0x14
 #define		BTB_TIMER_DISABLE	0x40
 #define CTEST1_REG                      0x15
 #define CTEST2_REG                      0x16
 #define CTEST3_REG                      0x17
 #define CTEST4_REG                      0x18
 #define         DISABLE_FIFO            0x00
 #define         SLBE                    0x10
 #define         SFWR                    0x08
 #define         BYTE_LANE0              0x04
 #define         BYTE_LANE1              0x05
 #define         BYTE_LANE2              0x06
 #define         BYTE_LANE3              0x07
 #define         SCSI_ZMODE              0x20
 #define         ZMODE                   0x40
 #define CTEST5_REG                      0x19
 #define         MASTER_CONTROL          0x10
 #define         DMA_DIRECTION           0x08
 #define CTEST7_REG                      0x1B
 #define		BURST_DISABLE		0x80 /* 710 only */
 #define		SEL_TIMEOUT_DISABLE	0x10 /* 710 only */
 #define         DFP                     0x08
 #define         EVP                     0x04
 #define         CTEST7_TT1              0x02
 #define		DIFF			0x01
 #define CTEST6_REG                      0x1A
 #define	TEMP_REG			0x1C
 #define	DFIFO_REG			0x20
 #define		FLUSH_DMA_FIFO		0x80
 #define		CLR_FIFO		0x40
 #define	ISTAT_REG			0x21
 #define		ABORT_OPERATION		0x80
 #define		SOFTWARE_RESET_710	0x40
 #define		DMA_INT_PENDING		0x01
 #define		SCSI_INT_PENDING	0x02
 #define		CONNECTED		0x08
 #define CTEST8_REG                      0x22
 #define         LAST_DIS_ENBL           0x01
 #define		SHORTEN_FILTERING	0x04
 #define		ENABLE_ACTIVE_NEGATION	0x10
 #define		GENERATE_RECEIVE_PARITY	0x20
 #define		CLR_FIFO_710		0x04
 #define		FLUSH_DMA_FIFO_710	0x08
 #define CTEST9_REG                      0x23
 #define	DBC_REG				0x24
 #define	DCMD_REG			0x27
 #define	DNAD_REG			0x28
 #define	DIEN_REG			0x39
 #define		BUS_FAULT		0x20
 #define 	ABORT_INT		0x10
 #define 	INT_INST_INT		0x04
 #define 	WD_INT			0x02
 #define 	ILGL_INST_INT		0x01
 #define	DCNTL_REG			0x3B
 #define		SOFTWARE_RESET		0x01
 #define		COMPAT_700_MODE		0x01
 #define 	SCRPTS_16BITS		0x20
 #define		EA_710			0x20
 #define		ASYNC_DIV_2_0		0x00
 #define		ASYNC_DIV_1_5		0x40
 #define		ASYNC_DIV_1_0		0x80
 #define		ASYNC_DIV_3_0		0xc0
 #define DMODE_710_REG			0x38
 #define	DMODE_700_REG			0x34
 #define		BURST_LENGTH_1		0x00
 #define		BURST_LENGTH_2		0x40
 #define		BURST_LENGTH_4		0x80
 #define		BURST_LENGTH_8		0xC0
 #define		DMODE_FC1		0x10
 #define		DMODE_FC2		0x20
 #define 	BW16			32
 #define 	MODE_286		16
 #define 	IO_XFER			8
 #define 	FIXED_ADDR		4

 #define DSP_REG                         0x2C
 #define DSPS_REG                        0x30

 /* Parameters to begin SDTR negotiations.  Empirically, I find that
  * the 53c700-66 cannot handle an offset >8, so don't change this  */
 #define NCR_700_MAX_OFFSET	8
 /* Was hoping the max offset would be greater for the 710, but
  * empirically it seems to be 8 also */
 #define NCR_710_MAX_OFFSET	8
 #define NCR_700_MIN_XFERP	1
 #define NCR_710_MIN_XFERP	0
 #define NCR_700_MIN_PERIOD	25 /* for SDTR message, 100ns */

 #define script_patch_32(dev, script, symbol, value) \
 { \
 	int i; \
 	dma_addr_t da = value; \
 	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
 		__u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]) + da; \
 		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
 		dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
 		DEBUG((" script, patching %s at %d to %pad\n", \
 		       #symbol, A_##symbol##_used[i], &da)); \
 	} \
 }

 #define script_patch_32_abs(dev, script, symbol, value) \
 { \
 	int i; \
 	dma_addr_t da = value; \
 	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
 		(script)[A_##symbol##_used[i]] = bS_to_host(da); \
 		dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
 		DEBUG((" script, patching %s at %d to %pad\n", \
 		       #symbol, A_##symbol##_used[i], &da)); \
 	} \
 }

 /* Used for patching the SCSI ID in the SELECT instruction */
 #define script_patch_ID(dev, script, symbol, value) \
 { \
 	int i; \
 	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
 		__u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]); \
 		val &= 0xff00ffff; \
 		val |= ((value) & 0xff) << 16; \
 		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
 		dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
 		DEBUG((" script, patching ID field %s at %d to 0x%x\n", \
 		       #symbol, A_##symbol##_used[i], val)); \
 	} \
 }

 #define script_patch_16(dev, script, symbol, value) \
 { \
 	int i; \
 	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
 		__u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]); \
 		val &= 0xffff0000; \
 		val |= ((value) & 0xffff); \
 		(script)[A_##symbol##_used[i]] = bS_to_host(val); \
 		dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
 		DEBUG((" script, patching short field %s at %d to 0x%x\n", \
 		       #symbol, A_##symbol##_used[i], val)); \
 	} \
 }


 static inline __u8
 NCR_700_readb(struct Scsi_Host *host, __u32 reg)
 {
 	const struct NCR_700_Host_Parameters *hostdata
 		= (struct NCR_700_Host_Parameters *)host->hostdata[0];

 	return ioread8(hostdata->base + (reg^bE));
 }

 static inline __u32
 NCR_700_readl(struct Scsi_Host *host, __u32 reg)
 {
 	const struct NCR_700_Host_Parameters *hostdata
 		= (struct NCR_700_Host_Parameters *)host->hostdata[0];
 	__u32 value = bEBus ? ioread32be(hostdata->base + reg) :
 		ioread32(hostdata->base + reg);
 #if 1
 	/* sanity check the register */
 	BUG_ON((reg & 0x3) != 0);
 #endif

 	return value;
 }

 static inline void
 NCR_700_writeb(__u8 value, struct Scsi_Host *host, __u32 reg)
 {
 	const struct NCR_700_Host_Parameters *hostdata
 		= (struct NCR_700_Host_Parameters *)host->hostdata[0];

 	iowrite8(value, hostdata->base + (reg^bE));
 }

 static inline void
 NCR_700_writel(__u32 value, struct Scsi_Host *host, __u32 reg)
 {
 	const struct NCR_700_Host_Parameters *hostdata
 		= (struct NCR_700_Host_Parameters *)host->hostdata[0];

 #if 1
 	/* sanity check the register */
 	BUG_ON((reg & 0x3) != 0);
 #endif

 	bEBus ? iowrite32be(value, hostdata->base + reg):
 		iowrite32(value, hostdata->base + reg);
 }

 #endif
	/* -- mode: c; c-basic-offset: 8 -- */

	/* Driver for 53c700 and 53c700-66 chips from NCR and Symbios
	*
	* Copyright (C) 2001 by James.Bottomley@HansenPartnership.com
	*/

	#ifndef _53C700_H
	#define _53C700_H

	#include <linux/interrupt.h>
	#include <asm/io.h>

	#include <scsi/scsi_device.h>
	#include <scsi/scsi_cmnd.h>

	/* Turn on for general debugging---too verbose for normal use */
	#undef NCR_700_DEBUG
	/* Debug the tag queues, checking hash queue allocation and deallocation
	* and search for duplicate tags */
	#undef NCR_700_TAG_DEBUG

	#ifdef NCR_700_DEBUG
	#define DEBUG(x) printk x
	#define DDEBUG(prefix, sdev, fmt, a...) \
	sdev_printk(prefix, sdev, fmt, ##a)
	#define CDEBUG(prefix, scmd, fmt, a...) \
	scmd_printk(prefix, scmd, fmt, ##a)
	#else
	#define DEBUG(x) do {} while (0)
	#define DDEBUG(prefix, scmd, fmt, a...) do {} while (0)
	#define CDEBUG(prefix, scmd, fmt, a...) do {} while (0)
	#endif

	/* The number of available command slots */
	#define NCR_700_COMMAND_SLOTS_PER_HOST 64
	/* The maximum number of Scatter Gathers we allow */
	#define NCR_700_SG_SEGMENTS 32
	/* The maximum number of luns (make this of the form 2^n) */
	#define NCR_700_MAX_LUNS 32
	#define NCR_700_LUN_MASK (NCR_700_MAX_LUNS - 1)
	/* Maximum number of tags the driver ever allows per device */
	#define NCR_700_MAX_TAGS 16
	/* Tag depth the driver starts out with (can be altered in sysfs) */
	#define NCR_700_DEFAULT_TAGS 4
	/* This is the default number of commands per LUN in the untagged case.
	* two is a good value because it means we can have one command active and
	* one command fully prepared and waiting
	*/
	#define NCR_700_CMD_PER_LUN 2
	/* magic byte identifying an internally generated REQUEST_SENSE command */
	#define NCR_700_INTERNAL_SENSE_MAGIC 0x42

	struct NCR_700_Host_Parameters;

	/* These are the externally used routines */
	struct Scsi_Host NCR_700_detect(struct scsi_host_template ,
	struct NCR_700_Host_Parameters , struct device );
	int NCR_700_release(struct Scsi_Host *host);
	irqreturn_t NCR_700_intr(int, void *);


	enum NCR_700_Host_State {
	NCR_700_HOST_BUSY,
	NCR_700_HOST_FREE,
	};

	struct NCR_700_SG_List {
	/* The following is a script fragment to move the buffer onto the
	* bus and then link the next fragment or return */
	#define SCRIPT_MOVE_DATA_IN 0x09000000
	#define SCRIPT_MOVE_DATA_OUT 0x08000000
	__u32 ins;
	__u32 pAddr;
	#define SCRIPT_NOP 0x80000000
	#define SCRIPT_RETURN 0x90080000
	};

	struct NCR_700_Device_Parameters {
	/* space for creating a request sense command. Really, except
	* for the annoying SCSI-2 requirement for LUN information in
	* cmnd[1], this could be in static storage */
	unsigned char cmnd[MAX_COMMAND_SIZE];
	__u8 depth;
	struct scsi_cmnd current_cmnd; / currently active command */
	};


	/* The SYNC negotiation sequence looks like:
	*
	* If DEV_NEGOTIATED_SYNC not set, tack and SDTR message on to the
	* initial identify for the device and set DEV_BEGIN_SYNC_NEGOTATION
	* If we get an SDTR reply, work out the SXFER parameters, squirrel
	* them away here, clear DEV_BEGIN_SYNC_NEGOTIATION and set
	* DEV_NEGOTIATED_SYNC. If we get a REJECT msg, squirrel
	*
	*
	* 0:7 SXFER_REG negotiated value for this device
	* 8:15 Current queue depth
	* 16 negotiated SYNC flag
	* 17 begin SYNC negotiation flag
	* 18 device supports tag queueing */
	#define NCR_700_DEV_NEGOTIATED_SYNC (1<<16)
	#define NCR_700_DEV_BEGIN_SYNC_NEGOTIATION (1<<17)
	#define NCR_700_DEV_PRINT_SYNC_NEGOTIATION (1<<19)

	static inline char NCR_700_get_sense_cmnd(struct scsi_device SDp)
	{
	struct NCR_700_Device_Parameters *hostdata = SDp->hostdata;

	return hostdata->cmnd;
	}

	static inline void
	NCR_700_set_depth(struct scsi_device *SDp, __u8 depth)
	{
	struct NCR_700_Device_Parameters *hostdata = SDp->hostdata;

	hostdata->depth = depth;
	}
	static inline __u8
	NCR_700_get_depth(struct scsi_device *SDp)
	{
	struct NCR_700_Device_Parameters *hostdata = SDp->hostdata;

	return hostdata->depth;
	}
	static inline int
	NCR_700_is_flag_set(struct scsi_device *SDp, __u32 flag)
	{
	return (spi_flags(SDp->sdev_target) & flag) == flag;
	}
	static inline int
	NCR_700_is_flag_clear(struct scsi_device *SDp, __u32 flag)
	{
	return (spi_flags(SDp->sdev_target) & flag) == 0;
	}
	static inline void
	NCR_700_set_flag(struct scsi_device *SDp, __u32 flag)
	{
	spi_flags(SDp->sdev_target) \|= flag;
	}
	static inline void
	NCR_700_clear_flag(struct scsi_device *SDp, __u32 flag)
	{
	spi_flags(SDp->sdev_target) &= ~flag;
	}

	enum NCR_700_tag_neg_state {
	NCR_700_START_TAG_NEGOTIATION = 0,
	NCR_700_DURING_TAG_NEGOTIATION = 1,
	NCR_700_FINISHED_TAG_NEGOTIATION = 2,
	};

	static inline enum NCR_700_tag_neg_state
	NCR_700_get_tag_neg_state(struct scsi_device *SDp)
	{
	return (enum NCR_700_tag_neg_state)((spi_flags(SDp->sdev_target)>>20) & 0x3);
	}

	static inline void
	NCR_700_set_tag_neg_state(struct scsi_device *SDp,
	enum NCR_700_tag_neg_state state)
	{
	/* clear the slot */
	spi_flags(SDp->sdev_target) &= ~(0x3 << 20);
	spi_flags(SDp->sdev_target) \|= ((__u32)state) << 20;
	}

	struct NCR_700_command_slot {
	struct NCR_700_SG_List SG[NCR_700_SG_SEGMENTS+1];
	struct NCR_700_SG_List *pSG;
	#define NCR_700_SLOT_MASK 0xFC
	#define NCR_700_SLOT_MAGIC 0xb8
	#define NCR_700_SLOT_FREE (0\|NCR_700_SLOT_MAGIC) /* slot may be used */
	#define NCR_700_SLOT_BUSY (1\|NCR_700_SLOT_MAGIC) /* slot has command active on HA */
	#define NCR_700_SLOT_QUEUED (2\|NCR_700_SLOT_MAGIC) /* slot has command to be made active on HA */
	__u8 state;
	#define NCR_700_FLAG_AUTOSENSE 0x01
	__u8 flags;
	__u8 pad1[2]; /* Needed for m68k where min alignment is 2 bytes */
	int tag;
	__u32 resume_offset;
	struct scsi_cmnd *cmnd;
	/* The pci_mapped address of the actual command in cmnd */
	dma_addr_t pCmd;
	__u32 temp;
	/* if this command is a pci_single mapping, holds the dma address
	* for later unmapping in the done routine */
	dma_addr_t dma_handle;
	/* historical remnant, now used to link free commands */
	struct NCR_700_command_slot *ITL_forw;
	};

	struct NCR_700_Host_Parameters {
	/* These must be filled in by the calling driver */
	int clock; /* board clock speed in MHz */
	void __iomem base; / the base for the port (copied to host) */
	struct device *dev;
	__u32 dmode_extra; /* adjustable bus settings */
	__u32 dcntl_extra; /* adjustable bus settings */
	__u32 ctest7_extra; /* adjustable bus settings */
	__u32 differential:1; /* if we are differential */
	#ifdef CONFIG_53C700_LE_ON_BE
	/* This option is for HP only. Set it if your chip is wired for
	* little endian on this platform (which is big endian) */
	__u32 force_le_on_be:1;
	#endif
	__u32 chip710:1; /* set if really a 710 not 700 */
	__u32 burst_length:4; /* set to 0 to disable 710 bursting */

	/* NOTHING BELOW HERE NEEDS ALTERING */
	__u32 fast:1; /* if we can alter the SCSI bus clock
	speed (so can negiotiate sync) */
	int sync_clock; /* The speed of the SYNC core */

	__u32 script; / pointer to script location */
	__u32 pScript; /* physical mem addr of script */

	enum NCR_700_Host_State state; /* protected by state lock */
	struct scsi_cmnd *cmd;
	/* Note: pScript contains the single consistent block of
	* memory. All the msgin, msgout and status are allocated in
	* this memory too (at separate cache lines). TOTAL_MEM_SIZE
	* represents the total size of this area */
	#define MSG_ARRAY_SIZE 8
	#define MSGOUT_OFFSET (L1_CACHE_ALIGN(sizeof(SCRIPT)))
	__u8 *msgout;
	#define MSGIN_OFFSET (MSGOUT_OFFSET + L1_CACHE_ALIGN(MSG_ARRAY_SIZE))
	__u8 *msgin;
	#define STATUS_OFFSET (MSGIN_OFFSET + L1_CACHE_ALIGN(MSG_ARRAY_SIZE))
	__u8 *status;
	#define SLOTS_OFFSET (STATUS_OFFSET + L1_CACHE_ALIGN(MSG_ARRAY_SIZE))
	struct NCR_700_command_slot *slots;
	#define TOTAL_MEM_SIZE (SLOTS_OFFSET + L1_CACHE_ALIGN(sizeof(struct NCR_700_command_slot) * NCR_700_COMMAND_SLOTS_PER_HOST))
	int saved_slot_position;
	int command_slot_count; /* protected by state lock */
	__u8 tag_negotiated;
	__u8 rev;
	__u8 reselection_id;
	__u8 min_period;

	/* Free list, singly linked by ITL_forw elements */
	struct NCR_700_command_slot *free_list;
	/* Completion for waited for ops, like reset, abort or
	* device reset.
	*
	* NOTE: relies on single threading in the error handler to
	* have only one outstanding at once */
	struct completion *eh_complete;
	};

	/*
	* 53C700 Register Interface - the offset from the Selected base
	* I/O address */
	#ifdef CONFIG_53C700_LE_ON_BE
	#define bE (hostdata->force_le_on_be ? 0 : 3)
	#define bSWAP (hostdata->force_le_on_be)
	#define bEBus (!hostdata->force_le_on_be)
	#elif defined(__BIG_ENDIAN)
	#define bE 3
	#define bSWAP 0
	#elif defined(__LITTLE_ENDIAN)
	#define bE 0
	#define bSWAP 0
	#else
	#error "__BIG_ENDIAN or __LITTLE_ENDIAN must be defined, did you include byteorder.h?"
	#endif
	#ifndef bEBus
	#ifdef CONFIG_53C700_BE_BUS
	#define bEBus 1
	#else
	#define bEBus 0
	#endif
	#endif
	#define bS_to_cpu(x) (bSWAP ? le32_to_cpu(x) : (x))
	#define bS_to_host(x) (bSWAP ? cpu_to_le32(x) : (x))

	/* NOTE: These registers are in the LE register space only, the required byte
	* swapping is done by the NCR_700_{read\|write}[b] functions */
	#define SCNTL0_REG 0x00
	#define FULL_ARBITRATION 0xc0
	#define PARITY 0x08
	#define ENABLE_PARITY 0x04
	#define AUTO_ATN 0x02
	#define SCNTL1_REG 0x01
	#define SLOW_BUS 0x80
	#define ENABLE_SELECT 0x20
	#define ASSERT_RST 0x08
	#define ASSERT_EVEN_PARITY 0x04
	#define SDID_REG 0x02
	#define SIEN_REG 0x03
	#define PHASE_MM_INT 0x80
	#define FUNC_COMP_INT 0x40
	#define SEL_TIMEOUT_INT 0x20
	#define SELECT_INT 0x10
	#define GROSS_ERR_INT 0x08
	#define UX_DISC_INT 0x04
	#define RST_INT 0x02
	#define PAR_ERR_INT 0x01
	#define SCID_REG 0x04
	#define SXFER_REG 0x05
	#define ASYNC_OPERATION 0x00
	#define SODL_REG 0x06
	#define SOCL_REG 0x07
	#define SFBR_REG 0x08
	#define SIDL_REG 0x09
	#define SBDL_REG 0x0A
	#define SBCL_REG 0x0B
	/* read bits */
	#define SBCL_IO 0x01
	/write bits /
	#define SYNC_DIV_AS_ASYNC 0x00
	#define SYNC_DIV_1_0 0x01
	#define SYNC_DIV_1_5 0x02
	#define SYNC_DIV_2_0 0x03
	#define DSTAT_REG 0x0C
	#define ILGL_INST_DETECTED 0x01
	#define WATCH_DOG_INTERRUPT 0x02
	#define SCRIPT_INT_RECEIVED 0x04
	#define ABORTED 0x10
	#define SSTAT0_REG 0x0D
	#define PARITY_ERROR 0x01
	#define SCSI_RESET_DETECTED 0x02
	#define UNEXPECTED_DISCONNECT 0x04
	#define SCSI_GROSS_ERROR 0x08
	#define SELECTED 0x10
	#define SELECTION_TIMEOUT 0x20
	#define FUNCTION_COMPLETE 0x40
	#define PHASE_MISMATCH 0x80
	#define SSTAT1_REG 0x0E
	#define SIDL_REG_FULL 0x80
	#define SODR_REG_FULL 0x40
	#define SODL_REG_FULL 0x20
	#define SSTAT2_REG 0x0F
	#define CTEST0_REG 0x14
	#define BTB_TIMER_DISABLE 0x40
	#define CTEST1_REG 0x15
	#define CTEST2_REG 0x16
	#define CTEST3_REG 0x17
	#define CTEST4_REG 0x18
	#define DISABLE_FIFO 0x00
	#define SLBE 0x10
	#define SFWR 0x08
	#define BYTE_LANE0 0x04
	#define BYTE_LANE1 0x05
	#define BYTE_LANE2 0x06
	#define BYTE_LANE3 0x07
	#define SCSI_ZMODE 0x20
	#define ZMODE 0x40
	#define CTEST5_REG 0x19
	#define MASTER_CONTROL 0x10
	#define DMA_DIRECTION 0x08
	#define CTEST7_REG 0x1B
	#define BURST_DISABLE 0x80 /* 710 only */
	#define SEL_TIMEOUT_DISABLE 0x10 /* 710 only */
	#define DFP 0x08
	#define EVP 0x04
	#define CTEST7_TT1 0x02
	#define DIFF 0x01
	#define CTEST6_REG 0x1A
	#define TEMP_REG 0x1C
	#define DFIFO_REG 0x20
	#define FLUSH_DMA_FIFO 0x80
	#define CLR_FIFO 0x40
	#define ISTAT_REG 0x21
	#define ABORT_OPERATION 0x80
	#define SOFTWARE_RESET_710 0x40
	#define DMA_INT_PENDING 0x01
	#define SCSI_INT_PENDING 0x02
	#define CONNECTED 0x08
	#define CTEST8_REG 0x22
	#define LAST_DIS_ENBL 0x01
	#define SHORTEN_FILTERING 0x04
	#define ENABLE_ACTIVE_NEGATION 0x10
	#define GENERATE_RECEIVE_PARITY 0x20
	#define CLR_FIFO_710 0x04
	#define FLUSH_DMA_FIFO_710 0x08
	#define CTEST9_REG 0x23
	#define DBC_REG 0x24
	#define DCMD_REG 0x27
	#define DNAD_REG 0x28
	#define DIEN_REG 0x39
	#define BUS_FAULT 0x20
	#define ABORT_INT 0x10
	#define INT_INST_INT 0x04
	#define WD_INT 0x02
	#define ILGL_INST_INT 0x01
	#define DCNTL_REG 0x3B
	#define SOFTWARE_RESET 0x01
	#define COMPAT_700_MODE 0x01
	#define SCRPTS_16BITS 0x20
	#define EA_710 0x20
	#define ASYNC_DIV_2_0 0x00
	#define ASYNC_DIV_1_5 0x40
	#define ASYNC_DIV_1_0 0x80
	#define ASYNC_DIV_3_0 0xc0
	#define DMODE_710_REG 0x38
	#define DMODE_700_REG 0x34
	#define BURST_LENGTH_1 0x00
	#define BURST_LENGTH_2 0x40
	#define BURST_LENGTH_4 0x80
	#define BURST_LENGTH_8 0xC0
	#define DMODE_FC1 0x10
	#define DMODE_FC2 0x20
	#define BW16 32
	#define MODE_286 16
	#define IO_XFER 8
	#define FIXED_ADDR 4

	#define DSP_REG 0x2C
	#define DSPS_REG 0x30

	/* Parameters to begin SDTR negotiations. Empirically, I find that
	* the 53c700-66 cannot handle an offset >8, so don't change this */
	#define NCR_700_MAX_OFFSET 8
	/* Was hoping the max offset would be greater for the 710, but
	* empirically it seems to be 8 also */
	#define NCR_710_MAX_OFFSET 8
	#define NCR_700_MIN_XFERP 1
	#define NCR_710_MIN_XFERP 0
	#define NCR_700_MIN_PERIOD 25 /* for SDTR message, 100ns */

	#define script_patch_32(dev, script, symbol, value) \
	{ \
	int i; \
	dma_addr_t da = value; \
	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
	__u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]) + da; \
	(script)[A_##symbol##_used[i]] = bS_to_host(val); \
	dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
	DEBUG((" script, patching %s at %d to %pad\n", \
	#symbol, A_##symbol##_used[i], &da)); \
	} \
	}

	#define script_patch_32_abs(dev, script, symbol, value) \
	{ \
	int i; \
	dma_addr_t da = value; \
	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
	(script)[A_##symbol##_used[i]] = bS_to_host(da); \
	dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
	DEBUG((" script, patching %s at %d to %pad\n", \
	#symbol, A_##symbol##_used[i], &da)); \
	} \
	}

	/* Used for patching the SCSI ID in the SELECT instruction */
	#define script_patch_ID(dev, script, symbol, value) \
	{ \
	int i; \
	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
	__u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]); \
	val &= 0xff00ffff; \
	val \|= ((value) & 0xff) << 16; \
	(script)[A_##symbol##_used[i]] = bS_to_host(val); \
	dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
	DEBUG((" script, patching ID field %s at %d to 0x%x\n", \
	#symbol, A_##symbol##_used[i], val)); \
	} \
	}

	#define script_patch_16(dev, script, symbol, value) \
	{ \
	int i; \
	for(i=0; i< (sizeof(A_##symbol##_used) / sizeof(__u32)); i++) { \
	__u32 val = bS_to_cpu((script)[A_##symbol##_used[i]]); \
	val &= 0xffff0000; \
	val \|= ((value) & 0xffff); \
	(script)[A_##symbol##_used[i]] = bS_to_host(val); \
	dma_cache_sync((dev), &(script)[A_##symbol##_used[i]], 4, DMA_TO_DEVICE); \
	DEBUG((" script, patching short field %s at %d to 0x%x\n", \
	#symbol, A_##symbol##_used[i], val)); \
	} \
	}


	static inline __u8
	NCR_700_readb(struct Scsi_Host *host, __u32 reg)
	{
	const struct NCR_700_Host_Parameters *hostdata
	= (struct NCR_700_Host_Parameters *)host->hostdata[0];

	return ioread8(hostdata->base + (reg^bE));
	}

	static inline __u32
	NCR_700_readl(struct Scsi_Host *host, __u32 reg)
	{
	const struct NCR_700_Host_Parameters *hostdata
	= (struct NCR_700_Host_Parameters *)host->hostdata[0];
	__u32 value = bEBus ? ioread32be(hostdata->base + reg) :
	ioread32(hostdata->base + reg);
	#if 1
	/* sanity check the register */
	BUG_ON((reg & 0x3) != 0);
	#endif

	return value;
	}

	static inline void
	NCR_700_writeb(__u8 value, struct Scsi_Host *host, __u32 reg)
	{
	const struct NCR_700_Host_Parameters *hostdata
	= (struct NCR_700_Host_Parameters *)host->hostdata[0];

	iowrite8(value, hostdata->base + (reg^bE));
	}

	static inline void
	NCR_700_writel(__u32 value, struct Scsi_Host *host, __u32 reg)
	{
	const struct NCR_700_Host_Parameters *hostdata
	= (struct NCR_700_Host_Parameters *)host->hostdata[0];

	#if 1
	/* sanity check the register */
	BUG_ON((reg & 0x3) != 0);
	#endif

	bEBus ? iowrite32be(value, hostdata->base + reg):
	iowrite32(value, hostdata->base + reg);
	}

	#endif