/*
 * dc395x.c
 *
 * Device Driver for Tekram DC395(U/UW/F), DC315(U)
 * PCI SCSI Bus Master Host Adapter
 * (SCSI chip set used Tekram ASIC TRM-S1040)
 *
 * Authors:
 *  C.L. Huang <ching@tekram.com.tw>
 *  Erich Chen <erich@tekram.com.tw>
 *  (C) Copyright 1995-1999 Tekram Technology Co., Ltd.
 *
 *  Kurt Garloff <garloff@suse.de>
 *  (C) 1999-2000 Kurt Garloff
 *
 *  Oliver Neukum <oliver@neukum.name>
 *  Ali Akcaagac <aliakc@web.de>
 *  Jamie Lenehan <lenehan@twibble.org>
 *  (C) 2003
 *
 * License: GNU GPL
 *
 *************************************************************************
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ************************************************************************
 */
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/delay.h>
#include <linux/ctype.h>
#include <linux/blkdev.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/pci.h>
#include <linux/list.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <asm/io.h>

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

#include "dc395x.h"

#define DC395X_NAME	"dc395x"
#define DC395X_BANNER	"Tekram DC395(U/UW/F), DC315(U) - ASIC TRM-S1040"
#define DC395X_VERSION	"v2.05, 2004/03/08"

/*---------------------------------------------------------------------------
                                  Features
 ---------------------------------------------------------------------------*/
/*
 * Set to disable parts of the driver
 */
/*#define DC395x_NO_DISCONNECT*/
/*#define DC395x_NO_TAGQ*/
/*#define DC395x_NO_SYNC*/
/*#define DC395x_NO_WIDE*/

/*---------------------------------------------------------------------------
                                  Debugging
 ---------------------------------------------------------------------------*/
/*
 * Types of debugging that can be enabled and disabled
 */
#define DBG_KG		0x0001
#define DBG_0		0x0002
#define DBG_1		0x0004
#define DBG_SG		0x0020
#define DBG_FIFO	0x0040
#define DBG_PIO		0x0080


/*
 * Set set of things to output debugging for.
 * Undefine to remove all debugging
 */
/*#define DEBUG_MASK (DBG_0|DBG_1|DBG_SG|DBG_FIFO|DBG_PIO)*/
/*#define  DEBUG_MASK	DBG_0*/


/*
 * Output a kernel mesage at the specified level and append the
 * driver name and a ": " to the start of the message
 */
#define dprintkl(level, format, arg...)  \
    printk(level DC395X_NAME ": " format , ## arg)


#ifdef DEBUG_MASK
/*
 * print a debug message - this is formated with KERN_DEBUG, then the
 * driver name followed by a ": " and then the message is output. 
 * This also checks that the specified debug level is enabled before
 * outputing the message
 */
#define dprintkdbg(type, format, arg...) \
	do { \
		if ((type) & (DEBUG_MASK)) \
			dprintkl(KERN_DEBUG , format , ## arg); \
	} while (0)

/*
 * Check if the specified type of debugging is enabled
 */
#define debug_enabled(type)	((DEBUG_MASK) & (type))

#else
/*
 * No debugging. Do nothing
 */
#define dprintkdbg(type, format, arg...) \
	do {} while (0)
#define debug_enabled(type)	(0)

#endif


#ifndef PCI_VENDOR_ID_TEKRAM
#define PCI_VENDOR_ID_TEKRAM                    0x1DE1	/* Vendor ID    */
#endif
#ifndef PCI_DEVICE_ID_TEKRAM_TRMS1040
#define PCI_DEVICE_ID_TEKRAM_TRMS1040           0x0391	/* Device ID    */
#endif


#define DC395x_LOCK_IO(dev,flags)		spin_lock_irqsave(((struct Scsi_Host *)dev)->host_lock, flags)
#define DC395x_UNLOCK_IO(dev,flags)		spin_unlock_irqrestore(((struct Scsi_Host *)dev)->host_lock, flags)

#define DC395x_read8(acb,address)		(u8)(inb(acb->io_port_base + (address)))
#define DC395x_read16(acb,address)		(u16)(inw(acb->io_port_base + (address)))
#define DC395x_read32(acb,address)		(u32)(inl(acb->io_port_base + (address)))
#define DC395x_write8(acb,address,value)	outb((value), acb->io_port_base + (address))
#define DC395x_write16(acb,address,value)	outw((value), acb->io_port_base + (address))
#define DC395x_write32(acb,address,value)	outl((value), acb->io_port_base + (address))

/* cmd->result */
#define RES_TARGET		0x000000FF	/* Target State */
#define RES_TARGET_LNX  STATUS_MASK	/* Only official ... */
#define RES_ENDMSG		0x0000FF00	/* End Message */
#define RES_DID			0x00FF0000	/* DID_ codes */
#define RES_DRV			0xFF000000	/* DRIVER_ codes */

#define MK_RES(drv,did,msg,tgt) ((int)(drv)<<24 | (int)(did)<<16 | (int)(msg)<<8 | (int)(tgt))
#define MK_RES_LNX(drv,did,msg,tgt) ((int)(drv)<<24 | (int)(did)<<16 | (int)(msg)<<8 | (int)(tgt)<<1)

#define SET_RES_TARGET(who,tgt) { who &= ~RES_TARGET; who |= (int)(tgt); }
#define SET_RES_TARGET_LNX(who,tgt) { who &= ~RES_TARGET_LNX; who |= (int)(tgt) << 1; }
#define SET_RES_MSG(who,msg) { who &= ~RES_ENDMSG; who |= (int)(msg) << 8; }
#define SET_RES_DID(who,did) { who &= ~RES_DID; who |= (int)(did) << 16; }
#define SET_RES_DRV(who,drv) { who &= ~RES_DRV; who |= (int)(drv) << 24; }

#define TAG_NONE 255

/*
 * srb->segement_x is the hw sg list. It is always allocated as a
 * DC395x_MAX_SG_LISTENTRY entries in a linear block which does not
 * cross a page boundy.
 */
#define SEGMENTX_LEN	(sizeof(struct SGentry)*DC395x_MAX_SG_LISTENTRY)


struct SGentry {
	u32 address;		/* bus! address */
	u32 length;
};

/* The SEEPROM structure for TRM_S1040 */
struct NVRamTarget {
	u8 cfg0;		/* Target configuration byte 0  */
	u8 period;		/* Target period                */
	u8 cfg2;		/* Target configuration byte 2  */
	u8 cfg3;		/* Target configuration byte 3  */
};

struct NvRamType {
	u8 sub_vendor_id[2];	/* 0,1  Sub Vendor ID   */
	u8 sub_sys_id[2];	/* 2,3  Sub System ID   */
	u8 sub_class;		/* 4    Sub Class       */
	u8 vendor_id[2];	/* 5,6  Vendor ID       */
	u8 device_id[2];	/* 7,8  Device ID       */
	u8 reserved;		/* 9    Reserved        */
	struct NVRamTarget target[DC395x_MAX_SCSI_ID];
						/** 10,11,12,13
						 ** 14,15,16,17
						 ** ....
						 ** ....
						 ** 70,71,72,73
						 */
	u8 scsi_id;		/* 74 Host Adapter SCSI ID      */
	u8 channel_cfg;		/* 75 Channel configuration     */
	u8 delay_time;		/* 76 Power on delay time       */
	u8 max_tag;		/* 77 Maximum tags              */
	u8 reserved0;		/* 78  */
	u8 boot_target;		/* 79  */
	u8 boot_lun;		/* 80  */
	u8 reserved1;		/* 81  */
	u16 reserved2[22];	/* 82,..125 */
	u16 cksum;		/* 126,127 */
};

struct ScsiReqBlk {
	struct list_head list;		/* next/prev ptrs for srb lists */
	struct DeviceCtlBlk *dcb;
	struct scsi_cmnd *cmd;

	struct SGentry *segment_x;	/* Linear array of hw sg entries (up to 64 entries) */
	dma_addr_t sg_bus_addr;	        /* Bus address of sg list (ie, of segment_x) */

	u8 sg_count;			/* No of HW sg entries for this request */
	u8 sg_index;			/* Index of HW sg entry for this request */
	size_t total_xfer_length;	/* Total number of bytes remaining to be transferred */
	size_t request_length;		/* Total number of bytes in this request */
	/*
	 * The sense buffer handling function, request_sense, uses
	 * the first hw sg entry (segment_x[0]) and the transfer
	 * length (total_xfer_length). While doing this it stores the
	 * original values into the last sg hw list
	 * (srb->segment_x[DC395x_MAX_SG_LISTENTRY - 1] and the
	 * total_xfer_length in xferred. These values are restored in
	 * pci_unmap_srb_sense. This is the only place xferred is used.
	 */
	size_t xferred;		        /* Saved copy of total_xfer_length */

	u16 state;

	u8 msgin_buf[6];
	u8 msgout_buf[6];

	u8 adapter_status;
	u8 target_status;
	u8 msg_count;
	u8 end_message;

	u8 tag_number;
	u8 status;
	u8 retry_count;
	u8 flag;

	u8 scsi_phase;
};

struct DeviceCtlBlk {
	struct list_head list;		/* next/prev ptrs for the dcb list */
	struct AdapterCtlBlk *acb;
	struct list_head srb_going_list;	/* head of going srb list */
	struct list_head srb_waiting_list;	/* head of waiting srb list */

	struct ScsiReqBlk *active_srb;
	u32 tag_mask;

	u16 max_command;

	u8 target_id;		/* SCSI Target ID  (SCSI Only) */
	u8 target_lun;		/* SCSI Log.  Unit (SCSI Only) */
	u8 identify_msg;
	u8 dev_mode;

	u8 inquiry7;		/* To store Inquiry flags */
	u8 sync_mode;		/* 0:async mode */
	u8 min_nego_period;	/* for nego. */
	u8 sync_period;		/* for reg.  */

	u8 sync_offset;		/* for reg. and nego.(low nibble) */
	u8 flag;
	u8 dev_type;
	u8 init_tcq_flag;
};

struct AdapterCtlBlk {
	struct Scsi_Host *scsi_host;

	unsigned long io_port_base;
	unsigned long io_port_len;

	struct list_head dcb_list;		/* head of going dcb list */
	struct DeviceCtlBlk *dcb_run_robin;
	struct DeviceCtlBlk *active_dcb;

	struct list_head srb_free_list;		/* head of free srb list */
	struct ScsiReqBlk *tmp_srb;
	struct timer_list waiting_timer;
	struct timer_list selto_timer;

	unsigned long last_reset;

	u16 srb_count;

	u8 sel_timeout;

	unsigned int irq_level;
	u8 tag_max_num;
	u8 acb_flag;
	u8 gmode2;

	u8 config;
	u8 lun_chk;
	u8 scan_devices;
	u8 hostid_bit;

	u8 dcb_map[DC395x_MAX_SCSI_ID];
	struct DeviceCtlBlk *children[DC395x_MAX_SCSI_ID][32];

	struct pci_dev *dev;

	u8 msg_len;

	struct ScsiReqBlk srb_array[DC395x_MAX_SRB_CNT];
	struct ScsiReqBlk srb;

	struct NvRamType eeprom;	/* eeprom settings for this adapter */
};


/*---------------------------------------------------------------------------
                            Forward declarations
 ---------------------------------------------------------------------------*/
static void data_out_phase0(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void data_in_phase0(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void command_phase0(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void status_phase0(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void msgout_phase0(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void msgin_phase0(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void data_out_phase1(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void data_in_phase1(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void command_phase1(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void status_phase1(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void msgout_phase1(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void msgin_phase1(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void nop0(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb,
		u16 *pscsi_status);
static void nop1(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb, 
		u16 *pscsi_status);
static void set_basic_config(struct AdapterCtlBlk *acb);
static void cleanup_after_transfer(struct AdapterCtlBlk *acb,
		struct ScsiReqBlk *srb);
static void reset_scsi_bus(struct AdapterCtlBlk *acb);
static void data_io_transfer(struct AdapterCtlBlk *acb,
		struct ScsiReqBlk *srb, u16 io_dir);
static void disconnect(struct AdapterCtlBlk *acb);
static void reselect(struct AdapterCtlBlk *acb);
static u8 start_scsi(struct AdapterCtlBlk *acb, struct DeviceCtlBlk *dcb,
		struct ScsiReqBlk *srb);
static inline void enable_msgout_abort(struct AdapterCtlBlk *acb,
		struct ScsiReqBlk *srb);
static void build_srb(struct scsi_cmnd *cmd, struct DeviceCtlBlk *dcb,
		struct ScsiReqBlk *srb);
static void doing_srb_done(struct AdapterCtlBlk *acb, u8 did_code,
		struct scsi_cmnd *cmd, u8 force);
static void scsi_reset_detect(struct AdapterCtlBlk *acb);
static void pci_unmap_srb(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb);
static void pci_unmap_srb_sense(struct AdapterCtlBlk *acb,
		struct ScsiReqBlk *srb);
static void srb_done(struct AdapterCtlBlk *acb, struct DeviceCtlBlk *dcb,
		struct ScsiReqBlk *srb);
static void request_sense(struct AdapterCtlBlk *acb, struct DeviceCtlBlk *dcb,
		struct ScsiReqBlk *srb);
static void set_xfer_rate(struct AdapterCtlBlk *acb,
		struct DeviceCtlBlk *dcb);
static void waiting_timeout(struct timer_list *t);


/*---------------------------------------------------------------------------
                                 Static Data
 ---------------------------------------------------------------------------*/
static u16 current_sync_offset = 0;

static void *dc395x_scsi_phase0[] = {
	data_out_phase0,/* phase:0 */
	data_in_phase0,	/* phase:1 */
	command_phase0,	/* phase:2 */
	status_phase0,	/* phase:3 */
	nop0,		/* phase:4 PH_BUS_FREE .. initial phase */
	nop0,		/* phase:5 PH_BUS_FREE .. initial phase */
	msgout_phase0,	/* phase:6 */
	msgin_phase0,	/* phase:7 */
};

static void *dc395x_scsi_phase1[] = {
	data_out_phase1,/* phase:0 */
	data_in_phase1,	/* phase:1 */
	command_phase1,	/* phase:2 */
	status_phase1,	/* phase:3 */
	nop1,		/* phase:4 PH_BUS_FREE .. initial phase */
	nop1,		/* phase:5 PH_BUS_FREE .. initial phase */
	msgout_phase1,	/* phase:6 */
	msgin_phase1,	/* phase:7 */
};

/*
 *Fast20:	000	 50ns, 20.0 MHz
 *		001	 75ns, 13.3 MHz
 *		010	100ns, 10.0 MHz
 *		011	125ns,  8.0 MHz
 *		100	150ns,  6.6 MHz
 *		101	175ns,  5.7 MHz
 *		110	200ns,  5.0 MHz
 *		111	250ns,  4.0 MHz
 *
 *Fast40(LVDS):	000	 25ns, 40.0 MHz
 *		001	 50ns, 20.0 MHz
 *		010	 75ns, 13.3 MHz
 *		011	100ns, 10.0 MHz
 *		100	125ns,  8.0 MHz
 *		101	150ns,  6.6 MHz
 *		110	175ns,  5.7 MHz
 *		111	200ns,  5.0 MHz
 */
/*static u8	clock_period[] = {12,19,25,31,37,44,50,62};*/

/* real period:48ns,76ns,100ns,124ns,148ns,176ns,200ns,248ns */
static u8 clock_period[] = { 12, 18, 25, 31, 37, 43, 50, 62 };
static u16 clock_speed[] = { 200, 133, 100, 80, 67, 58, 50, 40 };


/*---------------------------------------------------------------------------
                                Configuration
  ---------------------------------------------------------------------------*/
/*
 * Module/boot parameters currently effect *all* instances of the
 * card in the system.
 */

/*
 * Command line parameters are stored in a structure below.
 * These are the index's into the structure for the various
 * command line options.
 */
#define CFG_ADAPTER_ID		0
#define CFG_MAX_SPEED		1
#define CFG_DEV_MODE		2
#define CFG_ADAPTER_MODE	3
#define CFG_TAGS		4
#define CFG_RESET_DELAY		5

#define CFG_NUM			6	/* number of configuration items */


/*
 * Value used to indicate that a command line override
 * hasn't been used to modify the value.
 */
#define CFG_PARAM_UNSET -1


/*
 * Hold command line parameters.
 */
struct ParameterData {
	int value;		/* value of this setting */
	int min;		/* minimum value */
	int max;		/* maximum value */
	int def;		/* default value */
	int safe;		/* safe value */
};
static struct ParameterData cfg_data[] = {
	{ /* adapter id */
		CFG_PARAM_UNSET,
		0,
		15,
		7,
		7
	},
	{ /* max speed */
		CFG_PARAM_UNSET,
		  0,
		  7,
		  1,	/* 13.3Mhz */
		  4,	/*  6.7Hmz */
	},
	{ /* dev mode */
		CFG_PARAM_UNSET,
		0,
		0x3f,
		NTC_DO_PARITY_CHK | NTC_DO_DISCONNECT | NTC_DO_SYNC_NEGO |
			NTC_DO_WIDE_NEGO | NTC_DO_TAG_QUEUEING |
			NTC_DO_SEND_START,
		NTC_DO_PARITY_CHK | NTC_DO_SEND_START
	},
	{ /* adapter mode */
		CFG_PARAM_UNSET,
		0,
		0x2f,
		NAC_SCANLUN |
		NAC_GT2DRIVES | NAC_GREATER_1G | NAC_POWERON_SCSI_RESET
			/*| NAC_ACTIVE_NEG*/,
		NAC_GT2DRIVES | NAC_GREATER_1G | NAC_POWERON_SCSI_RESET | 0x08
	},
	{ /* tags */
		CFG_PARAM_UNSET,
		0,
		5,
		3,	/* 16 tags (??) */
		2,
	},
	{ /* reset delay */
		CFG_PARAM_UNSET,
		0,
		180,
		1,	/* 1 second */
		10,	/* 10 seconds */
	}
};


/*
 * Safe settings. If set to zero the BIOS/default values with
 * command line overrides will be used. If set to 1 then safe and
 * slow settings will be used.
 */
static bool use_safe_settings = 0;
module_param_named(safe, use_safe_settings, bool, 0);
MODULE_PARM_DESC(safe, "Use safe and slow settings only. Default: false");


module_param_named(adapter_id, cfg_data[CFG_ADAPTER_ID].value, int, 0);
MODULE_PARM_DESC(adapter_id, "Adapter SCSI ID. Default 7 (0-15)");

module_param_named(max_speed, cfg_data[CFG_MAX_SPEED].value, int, 0);
MODULE_PARM_DESC(max_speed, "Maximum bus speed. Default 1 (0-7) Speeds: 0=20, 1=13.3, 2=10, 3=8, 4=6.7, 5=5.8, 6=5, 7=4 Mhz");

module_param_named(dev_mode, cfg_data[CFG_DEV_MODE].value, int, 0);
MODULE_PARM_DESC(dev_mode, "Device mode.");

module_param_named(adapter_mode, cfg_data[CFG_ADAPTER_MODE].value, int, 0);
MODULE_PARM_DESC(adapter_mode, "Adapter mode.");

module_param_named(tags, cfg_data[CFG_TAGS].value, int, 0);
MODULE_PARM_DESC(tags, "Number of tags (1<<x). Default 3 (0-5)");

module_param_named(reset_delay, cfg_data[CFG_RESET_DELAY].value, int, 0);
MODULE_PARM_DESC(reset_delay, "Reset delay in seconds. Default 1 (0-180)");


/**
 * set_safe_settings - if the use_safe_settings option is set then
 * set all values to the safe and slow values.
 **/
static void set_safe_settings(void)
{
	if (use_safe_settings)
	{
		int i;

		dprintkl(KERN_INFO, "Using safe settings.\n");
		for (i = 0; i < CFG_NUM; i++)
		{
			cfg_data[i].value = cfg_data[i].safe;
		}
	}
}


/**
 * fix_settings - reset any boot parameters which are out of range
 * back to the default values.
 **/
static void fix_settings(void)
{
	int i;

	dprintkdbg(DBG_1,
		"setup: AdapterId=%08x MaxSpeed=%08x DevMode=%08x "
		"AdapterMode=%08x Tags=%08x ResetDelay=%08x\n",
		cfg_data[CFG_ADAPTER_ID].value,
		cfg_data[CFG_MAX_SPEED].value,
		cfg_data[CFG_DEV_MODE].value,
		cfg_data[CFG_ADAPTER_MODE].value,
		cfg_data[CFG_TAGS].value,
		cfg_data[CFG_RESET_DELAY].value);
	for (i = 0; i < CFG_NUM; i++)
	{
		if (cfg_data[i].value < cfg_data[i].min
		    || cfg_data[i].value > cfg_data[i].max)
			cfg_data[i].value = cfg_data[i].def;
	}
}



/*
 * Mapping from the eeprom delay index value (index into this array)
 * to the number of actual seconds that the delay should be for.
 */
static char eeprom_index_to_delay_map[] =
	{ 1, 3, 5, 10, 16, 30, 60, 120 };


/**
 * eeprom_index_to_delay - Take the eeprom delay setting and convert it
 * into a number of seconds.
 *
 * @eeprom: The eeprom structure in which we find the delay index to map.
 **/
static void eeprom_index_to_delay(struct NvRamType *eeprom)
{
	eeprom->delay_time = eeprom_index_to_delay_map[eeprom->delay_time];
}


/**
 * delay_to_eeprom_index - Take a delay in seconds and return the
 * closest eeprom index which will delay for at least that amount of
 * seconds.
 *
 * @delay: The delay, in seconds, to find the eeprom index for.
 **/
static int delay_to_eeprom_index(int delay)
{
	u8 idx = 0;
	while (idx < 7 && eeprom_index_to_delay_map[idx] < delay)
		idx++;
	return idx;
}


/**
 * eeprom_override - Override the eeprom settings, in the provided
 * eeprom structure, with values that have been set on the command
 * line.
 *
 * @eeprom: The eeprom data to override with command line options.
 **/
static void eeprom_override(struct NvRamType *eeprom)
{
	u8 id;

	/* Adapter Settings */
	if (cfg_data[CFG_ADAPTER_ID].value != CFG_PARAM_UNSET)
		eeprom->scsi_id = (u8)cfg_data[CFG_ADAPTER_ID].value;

	if (cfg_data[CFG_ADAPTER_MODE].value != CFG_PARAM_UNSET)
		eeprom->channel_cfg = (u8)cfg_data[CFG_ADAPTER_MODE].value;

	if (cfg_data[CFG_RESET_DELAY].value != CFG_PARAM_UNSET)
		eeprom->delay_time = delay_to_eeprom_index(
					cfg_data[CFG_RESET_DELAY].value);

	if (cfg_data[CFG_TAGS].value != CFG_PARAM_UNSET)
		eeprom->max_tag = (u8)cfg_data[CFG_TAGS].value;

	/* Device Settings */
	for (id = 0; id < DC395x_MAX_SCSI_ID; id++) {
		if (cfg_data[CFG_DEV_MODE].value != CFG_PARAM_UNSET)
			eeprom->target[id].cfg0 =
				(u8)cfg_data[CFG_DEV_MODE].value;

		if (cfg_data[CFG_MAX_SPEED].value != CFG_PARAM_UNSET)
			eeprom->target[id].period =
				(u8)cfg_data[CFG_MAX_SPEED].value;

	}
}


/*---------------------------------------------------------------------------
 ---------------------------------------------------------------------------*/

static unsigned int list_size(struct list_head *head)
{
	unsigned int count = 0;
	struct list_head *pos;
	list_for_each(pos, head)
		count++;
	return count;
}


static struct DeviceCtlBlk *dcb_get_next(struct list_head *head,
		struct DeviceCtlBlk *pos)
{
	int use_next = 0;
	struct DeviceCtlBlk* next = NULL;
	struct DeviceCtlBlk* i;

	if (list_empty(head))
		return NULL;

	/* find supplied dcb and then select the next one */
	list_for_each_entry(i, head, list)
		if (use_next) {
			next = i;
			break;
		} else if (i == pos) {
			use_next = 1;
		}
	/* if no next one take the head one (ie, wraparound) */
	if (!next)
        	list_for_each_entry(i, head, list) {
        		next = i;
        		break;
        	}

	return next;
}


static void free_tag(struct DeviceCtlBlk *dcb, struct ScsiReqBlk *srb)
{
	if (srb->tag_number < 255) {
		dcb->tag_mask &= ~(1 << srb->tag_number);	/* free tag mask */
		srb->tag_number = 255;
	}
}


/* Find cmd in SRB list */
static inline struct ScsiReqBlk *find_cmd(struct scsi_cmnd *cmd,
		struct list_head *head)
{
	struct ScsiReqBlk *i;
	list_for_each_entry(i, head, list)
		if (i->cmd == cmd)
			return i;
	return NULL;
}

/* Sets the timer to wake us up */
static void waiting_set_timer(struct AdapterCtlBlk *acb, unsigned long to)
{
	if (timer_pending(&acb->waiting_timer))
		return;
	if (time_before(jiffies + to, acb->last_reset - HZ / 2))
		acb->waiting_timer.expires =
		    acb->last_reset - HZ / 2 + 1;
	else
		acb->waiting_timer.expires = jiffies + to + 1;
	add_timer(&acb->waiting_timer);
}


/* Send the next command from the waiting list to the bus */
static void waiting_process_next(struct AdapterCtlBlk *acb)
{
	struct DeviceCtlBlk *start = NULL;
	struct DeviceCtlBlk *pos;
	struct DeviceCtlBlk *dcb;
	struct ScsiReqBlk *srb;
	struct list_head *dcb_list_head = &acb->dcb_list;

	if (acb->active_dcb
	    || (acb->acb_flag & (RESET_DETECT + RESET_DONE + RESET_DEV)))
		return;

	if (timer_pending(&acb->waiting_timer))
		del_timer(&acb->waiting_timer);

	if (list_empty(dcb_list_head))
		return;

	/*
	 * Find the starting dcb. Need to find it again in the list
	 * since the list may have changed since we set the ptr to it
	 */
	list_for_each_entry(dcb, dcb_list_head, list)
		if (dcb == acb->dcb_run_robin) {
			start = dcb;
			break;
		}
	if (!start) {
		/* This can happen! */
		start = list_entry(dcb_list_head->next, typeof(*start), list);
		acb->dcb_run_robin = start;
	}


	/*
	 * Loop over the dcb, but we start somewhere (potentially) in
	 * the middle of the loop so we need to manully do this.
	 */
	pos = start;
	do {
		struct list_head *waiting_list_head = &pos->srb_waiting_list;

		/* Make sure, the next another device gets scheduled ... */
		acb->dcb_run_robin = dcb_get_next(dcb_list_head,
						  acb->dcb_run_robin);

		if (list_empty(waiting_list_head) ||
		    pos->max_command <= list_size(&pos->srb_going_list)) {
			/* move to next dcb */
			pos = dcb_get_next(dcb_list_head, pos);
		} else {
			srb = list_entry(waiting_list_head->next,
					 struct ScsiReqBlk, list);

			/* Try to send to the bus */
			if (!start_scsi(acb, pos, srb))
				list_move(&srb->list, &pos->srb_going_list);
			else
				waiting_set_timer(acb, HZ/50);
			break;
		}
	} while (pos != start);
}


/* Wake up waiting queue */
static void waiting_timeout(struct timer_list *t)
{
	unsigned long flags;
	struct AdapterCtlBlk *acb = from_timer(acb, t, waiting_timer);
	dprintkdbg(DBG_1,
		"waiting_timeout: Queue woken up by timer. acb=%p\n", acb);
	DC395x_LOCK_IO(acb->scsi_host, flags);
	waiting_process_next(acb);
	DC395x_UNLOCK_IO(acb->scsi_host, flags);
}


/* Get the DCB for a given ID/LUN combination */
static struct DeviceCtlBlk *find_dcb(struct AdapterCtlBlk *acb, u8 id, u8 lun)
{
	return acb->children[id][lun];
}


/* Send SCSI Request Block (srb) to adapter (acb) */
static void send_srb(struct AdapterCtlBlk *acb, struct ScsiReqBlk *srb)
{
	struct DeviceCtlBlk *dcb = srb->dcb;

	if (dcb->max_command <= list_size(&dcb->srb_going_list) ||
	    acb->active_dcb ||
	    (acb->acb_flag & (RESET_DETECT + RESET_DONE + RESET_DEV))) {
		list_add_tail(&srb->list, &dcb->srb_waiting_list);
		waiting_process_next(acb);
		return;
	}

	if (!start_scsi(acb, dcb, srb)) {
		list_add_tail(&srb->list, &dcb->srb_going_list);
	} else {
		list_add(&srb->list, &dcb->srb_waiting_list);
		waiting_set_timer(acb, HZ / 50);
	}
}

/* Prepare SRB for being sent to Device DCB w/ command *cmd */
static void build_srb(struct scsi_cmnd *cmd, struct DeviceCtlBlk *dcb,
		struct ScsiReqBlk *srb)
{
	int nseg;
	enum dma_data_direction dir = cmd->sc_data_direction;
	dprintkdbg(DBG_0, "build_srb: (0x%p) <%02i-%i>\n",
		cmd, dcb->target_id, dcb->target_lun);

	srb->dcb = dcb;
	srb->cmd = cmd;
	srb->sg_count = 0;
	srb->total_xfer_length = 0;
	srb->sg_bus_addr = 0;
	srb->sg_index = 0;
	srb->adapter_status = 0;
	srb->target_status = 0;
	srb->msg_count = 0;
	srb->status = 0;
	srb->flag = 0;
	srb->state = 0;
	srb->retry_count = 0;
	srb->tag_number = TAG_NONE;
	srb->scsi_phase = PH_BUS_FREE;	/* initial phase */
	srb->end_message = 0;

	nseg = scsi_dma_map(cmd);
	BUG_ON(nseg < 0);

	if (dir == PCI_DMA_NONE || !nseg) {
		dprintkdbg(DBG_0,
			"build_srb: [0] len=%d buf=%p use_sg=%d !MAP=%08x\n",
			   cmd->bufflen, scsi_sglist(cmd), scsi_sg_count(cmd),
			   srb->segment_x[0].address);
	} else {
		int i;
		u32 reqlen = scsi_bufflen(cmd);
		struct scatterlist *sg;
		struct SGentry *sgp = srb->segment_x;

		srb->sg_count = nseg;

		dprintkdbg(DBG_0,
			   "build_srb: [n] len=%d buf=%p use_sg=%d segs=%d\n",
			   reqlen, scsi_sglist(cmd), scsi_sg_count(cmd),
			   srb->sg_count);

		scsi_for_each_sg(cmd, sg, srb->sg_count, i) {
			u32 busaddr = (u32)sg_dma_address(sg);
			u32 seglen = (u32)sg->length;
			sgp[i].address = busaddr;
			sgp[i].length = seglen;
			srb->total_xfer_length += seglen;
		}
		sgp += srb->sg_count - 1;

		/*
		 * adjust last page if too big as it is allocated
		 * on even page boundaries
		 */
		if (srb->total_xfer_length > reqlen) {
			sgp->length -= (srb->total_xfer_length - reqlen);
			srb->total_xfer_length = reqlen;
		}

		/* Fixup for WIDE padding - make sure length is even */
		if (dcb->sync_period & WIDE_SYNC &&
		    srb->total_xfer_length % 2) {
			srb->total_xfer_length++;
			sgp->length++;
		}

		srb->sg_bus_addr = dma_map_single(&dcb->acb->dev->dev,
				srb->segment_x, SEGMENTX_LEN, DMA_TO_DEVICE);

		dprintkdbg(DBG_SG, "build_srb: [n] map sg %p->%08x(%05x)\n",
			srb->segment_x, srb->sg_bus_addr, SEGMENTX_LEN);
	}

	srb->request_length = srb->total_xfer_length;
}


/**
 * dc395x_queue_command - queue scsi command passed from the mid
 * layer, invoke 'done' on completion
 *
 * @cmd: pointer to scsi command object
 * @done: function pointer to be invoked on completion
 *
 * Returns 1 if the adapter (host) is busy, else returns 0. One
 * reason for an adapter to be busy is that the number
 * of outstanding queued commands is already equal to
 * struct Scsi_Host::can_queue .
 *
 * Required: if struct Scsi_Host::can_queue is ever non-zero
 *           then this function is required.
 *
 * Locks: struct Scsi_Host::host_lock held on entry (with "irqsave")
 *        and is expected to be held on return.
 *
 **/
static int dc395x_queue_command_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
{
	struct DeviceCtlBlk *dcb;
	struct ScsiReqBlk *srb;
	struct AdapterCtlBlk *acb =
	    (struct AdapterCtlBlk *)cmd->device->host->hostdata;
	dprintkdbg(DBG_0, "queue_command: (0x%p) <%02i-%i> cmnd=0x%02x\n",
		cmd, cmd->device->id, (u8)cmd->device->lun, cmd->cmnd[0]);

	/* Assume BAD_TARGET; will be cleared later */
	cmd->result = DID_BAD_TARGET << 16;

	/* ignore invalid targets */
	if (cmd->device->id >= acb->scsi_host->max_id ||
	    cmd->device->lun >= acb->scsi_host->max_lun ||
	    cmd->device->lun >31) {
		goto complete;
	}

	/* does the specified lun on the specified device exist */
	if (!(acb->dcb_map[cmd->device->id] & (1 << cmd->device->lun))) {
		dprintkl(KERN_INFO, "queue_command: Ignore target <%02i-%i>\n",
			cmd->device->id, (u8)cmd->device->lun);
		goto complete;
	}

	/* do we have a DCB for the device */
	dcb = find_dcb(acb, cmd->device->id, cmd->device->lun);
	if (!dcb) {
		/* should never happen */
		dprintkl(KERN_ERR, "queue_command: No such device <%02i-%i>",
			cmd->device->id, (u8)cmd->device->lun);
		goto complete;
	}

	/* set callback and clear result in the command */
	cmd->scsi_done = done;
	cmd->result = 0;

	srb = list_first_entry_or_null(&acb->srb_free_list,
			struct ScsiReqBlk, list);
	if (!srb) {
		/*
		 * Return 1 since we are unable to queue this command at this
		 * point in time.
		 */
		dprintkdbg(DBG_0, "queue_command: No free srb's\n");
		return 1;
	}
	list_del(&srb->list);

	build_srb(cmd, dcb, srb);

	if (!list_empty(&dcb->srb_waiting_list)) {
		/* append to waiting queue */
		list_add_tail(&srb->list, &dcb->srb_waiting_list);
		waiting_process_next(acb);
	} else {
		/* process immediately */
		send_srb(acb, srb);
	}
	dprintkdbg(DBG_1, "queue_command: (0x%p) done\n", cmd);
	return 0;

complete:
	/*
	 * Complete the command immediatey, and then return 0 to
	 * indicate that we have handled the command. This is usually
	 * done when the commad is for things like non existent
	 * devices.
	 */
	done(cmd);
	return 0;
}

static DEF_SCSI_QCMD(dc395x_queue_command)

static void dump_register_info(struct AdapterCtlBlk *acb,
		struct DeviceCtlBlk *dcb, struct ScsiReqBlk *srb)
{
	u16 pstat;
	struct pci_dev *dev = acb->dev;
	pci_read_config_word(dev, PCI_STATUS, &pstat);
	if (!dcb)
		dcb = acb->active_dcb;
	if (!srb && dcb)
		srb = dcb->active_srb;
	if (srb) {
		if (!srb->cmd)
			dprintkl(KERN_INFO, "dump: srb=%p cmd=%p OOOPS!\n",
				srb, srb->cmd);
		else
			dprintkl(KERN_INFO, "dump: srb=%p cmd=%p "
				 "cmnd=0x%02x <%02i-%i>\n",
				srb, srb->cmd,
				srb->cmd->cmnd[0], srb->cmd->device->id,
				(u8)srb->cmd->device->lun);
		printk("  sglist=%p cnt=%i idx=%i len=%zu\n",
		       srb->segment_x, srb->sg_count, srb->sg_index,
		       srb->total_xfer_length);
		printk("  state=0x%04x status=0x%02x phase=0x%02x (%sconn.)\n",
		       srb->state, srb->status, srb->scsi_phase,
		       (acb->active_dcb) ? "" : "not");
	}
	dprintkl(KERN_INFO, "dump: SCSI{status=0x%04x fifocnt=0x%02x "
		"signals=0x%02x irqstat=0x%02x sync=0x%02x target=0x%02x "
		"rselid=0x%02x ctr=0x%08x irqen=0x%02x config=0x%04x "
		"config2=0x%02x cmd=0x%02x selto=0x%02x}\n",
		DC395x_read16(acb, TRM_S1040_SCSI_STATUS),
		DC395x_read8(acb, TRM_S1040_SCSI_FIFOCNT),
		DC395x_read8(acb, TRM_S1040_SCSI_SIGNAL),
		DC395x_read8(acb, TRM_S1040_SCSI_INTSTATUS),
		DC395x_read8(acb, TRM_S1040_SCSI_SYNC),
		DC395x_read8(acb, TRM_S1040_SCSI_TARGETID),
		DC395x_read8(acb, TRM_S1040_SCSI_IDMSG),
		DC395x_read32(acb, TRM_S1040_SCSI_COUNTER),
		DC395x_read8(acb, TRM_S1040_SCSI_INTEN),
		DC395x_read16(acb, TRM_S1040_SCSI_CONFIG0),
		DC395x_read8(acb, TRM_S1040_SCSI_CONFIG2),
		DC395x_read8(acb, TRM_S1040_SCSI_COMMAND),
		DC395x_read8(acb, TRM_S1040_SCSI_TIMEOUT));
	dprintkl(KERN_INFO, "dump: DMA{cmd=0x%04x fifocnt=0x%02x fstat=0x%02x "
		"irqstat=0x%02x irqen=0x%02x cfg=0x%04x tctr=0x%08x "
		"ctctr=0x%08x addr=0x%08x:0x%08x}\n",
		DC395x_read16(acb, TRM_S1040_DMA_COMMAND),
		DC395x_read8(acb, TRM_S1040_DMA_FIFOCNT),
		DC395x_read8(acb, TRM_S1040_DMA_FIFOSTAT),
		DC395x_read8(acb, TRM_S1040_DMA_STATUS),
		DC395x_read8(acb, TRM_S1040_DMA_INTEN),
		DC395x_read16(acb, TRM_S1040_DMA_CONFIG),
		DC395x_read32(acb, TRM_S1040_DMA_XCNT),
		DC395x_read32(acb, TRM_S1040_DMA_CXCNT),
		DC395x_read32(acb, TRM_S1040_DMA_XHIGHADDR),
		DC395x_read32(acb, TRM_S1040_DMA_XLOWADDR));
	dprintkl(KERN_INFO, "dump: gen{gctrl=0x%02x gstat=0x%02x gtmr=0x%02x} "
		"pci{status=0x%04x}\n",
		DC395x_read8(acb, TRM_S1040_GEN_CONTROL),
		DC395x_read8(acb, TRM_S1040_GEN_STATUS),
		DC395x_read8(acb, TRM_S1040_GEN_TIMER),
		pstat);
}


static inline void clear_fifo(struct AdapterCtlBlk *acb, char *txt)
{
#if debug_enabled(DBG_FIFO)
	u8 lines = DC395x_read8(acb, TRM_S1040_SCSI_SIGNAL);
	u8 fifocnt = DC395x_read8(acb, TRM_S1040_SCSI_FIFOCNT);
	if (!(fifocnt & 0x40))
		dprintkdbg(DBG_FIFO,
			"clear_fifo: (%i bytes) on phase %02x in %s\n",
			fifocnt & 0x3f, lines, txt);
#endif
	DC395x_write16(acb, TRM_S1040_SCSI_CONTROL, DO_CLRFIFO);
}


static void reset_dev_param(struct AdapterCtlBlk *acb)
{
	struct DeviceCtlBlk *dcb;
	struct NvRamType *eeprom = &acb->eeprom;
	dprintkdbg(DBG_0, "reset_dev_param: acb=%p\n", acb);

	list_for_each_entry(dcb, &acb->dcb_list, list) {
		u8 period_index;

		dcb->sync_mode &= ~(SYNC_NEGO_DONE + WIDE_NEGO_DONE);
		dcb->sync_period = 0;
		dcb->sync_offset = 0;

		dcb->dev_mode = eeprom->target[dcb->target_id].cfg0;
		period_index = eeprom->target[dcb->target_id].period & 0x07;
		dcb->min_nego_period = clock_period[period_index];
		if (!(dcb->dev_mode & NTC_DO_WIDE_NEGO)
		    || !(acb->config & HCC_WIDE_CARD))
			dcb->sync_mode &= ~WIDE_NEGO_ENABLE;
	}
}


/*
 * perform a hard reset on the SCSI bus
 * @cmd - some command for this host (for fetching hooks)
 * Returns: SUCCESS (0x2002) on success, else FAILED (0x2003).
 */
static int __dc395x_eh_bus_reset(struct scsi_cmnd *cmd)
{
	struct AdapterCtlBlk *acb =
		(struct AdapterCtlBlk *)cmd->device->host->hostdata;
	dprintkl(KERN_INFO,
		"eh_bus_reset: (0%p) target=<%02i-%i> cmd=%p\n",
		cmd, cmd->device->id, (u8)cmd->device->lun, cmd);

	if (timer_pending(&acb->waiting_timer))
		del_timer(&acb->waiting_timer);

	/*
	 * disable interrupt    
	 */
	DC395x_write8(acb, TRM_S1040_DMA_INTEN, 0x00);
	DC395x_write8(acb, TRM_S1040_SCSI_INTEN, 0x00);
	DC395x_write8(acb, TRM_S1040_SCSI_CONTROL, DO_RSTMODULE);
	DC395x_write8(acb, TRM_S1040_DMA_CONTROL, DMARESETMODULE);

	reset_scsi_bus(acb);
	udelay(500);

	/* We may be in serious trouble. Wait some seconds */
	acb->last_reset =
	    jiffies + 3 * HZ / 2 +
	    HZ * acb->eeprom.delay_time;

	/*
	 * re-enable interrupt      
	 */
	/* Clear SCSI FIFO          */
	DC395x_write8(acb, TRM_S1040_DMA_CONTROL, CLRXFIFO);
	clear_fifo(acb, "eh_bus_reset");
	/* Delete pending IRQ */
	DC395x_read8(acb, TRM_S1040_SCSI_INTSTATUS);
	set_basic_config(acb);

	reset_dev_param(acb);
	doing_srb_done(acb, DID_RESET, cmd, 0);
	acb->active_dcb = NULL;
	acb->acb_flag = 0;	/* RESET_DETECT, RESET_DONE ,RESET_DEV */
	waiting_process_next(acb);

	return SUCCESS;
}

static int dc395x_eh_bus_reset(struct scsi_cmnd *cmd)
{
	int rc;

	spin_lock_irq(cmd->device->host->host_lock);
	rc = __dc395x_eh_bus_reset(cmd);
	spin_unlock_irq(cmd->device->host->host_lock);

	return rc;
}

/*
 * abort an errant SCSI command
 * @cmd - command to be aborted
 * Returns: SUCCESS (0x2002) on success, else FAILED (0x2003).
 */
static int dc395x_eh_abort(struct scsi_cmnd *cmd)
{
	/*
	 * Look into our command queues: If it has not been sent already,
	 * we remove it and return success. Otherwise fail.
	 */
	struct AdapterCtlBlk *acb =
	    (struct AdapterCtlBlk *)cmd->device->host->hostdata;
	struct DeviceCtlBlk *dcb;
	struct ScsiReqBlk *srb;
	dprintkl(KERN_INFO, "eh_abort: (0x%p) target=<%02i-%i> cmd=%p\n",
		cmd, cmd->device->id, (u8)cmd->device->lun, cmd);

	dcb = find_dcb(acb, cmd->device->id, cmd->device->lun);
	if (!dcb) {
		dprintkl(KERN_DEBUG, "eh_abort: No such device\n");
		return FAILED;
	}

	srb = find_cmd(cmd, &dcb->srb_waiting_list);
	if (srb) {
		list_del(&srb->list);
		pci_unmap_srb_sense(acb, srb);
		pci_unmap_srb(acb, srb);
		free_tag(dcb, srb);
		list_add_tail(&srb->list, &acb->srb_free_list);
		dprintkl(KERN_DEBUG, "eh_abort: Command was waiting\n");
		cmd->result = DID_ABORT << 16;
		return SUCCESS;
	}
	srb = find_cmd(cmd, &dcb->srb_going_list);
	if (srb) {
		dprintkl(KERN_DEBUG, "eh_abort: Command in progress\n");
		/* XXX: Should abort the command here */
	} else {
		dprintkl(KERN_DEBUG, "eh_abort: Command not found\n");
	}
	return FAILED;
}


/* SDTR */
static void build_sdtr(struct AdapterCtlBlk *acb, struct DeviceCtlBlk *dcb,
		struct ScsiReqBlk *srb)
{
	u8 *ptr = srb->msgout_buf + srb->msg_count;
	if (srb->msg_count > 1) {
		dprintkl(KERN_INFO,
			"build_sdtr: msgout_buf BUSY (%i: %02x %02x)\n",
			srb->msg_count, srb->msgout_buf[0],
			srb->msgout_buf[1]);
		return;
	}
	if (!(dcb->dev_mode & NTC_DO_SYNC_NEGO)) {
		dcb->sync_offset = 0;
		dcb->min_nego_period = 200 >> 2;
	} else if (dcb->sync_offset == 0)
		dcb->sync_offset = SYNC_NEGO_OFFSET;

	*ptr++ = MSG_EXTENDED;	/* (01h) */
	*ptr++ = 3;		/* length */
	*ptr++ = EXTENDED_SDTR;	/* (01h) */
	*ptr++ = dcb->min_nego_period;	/* Transfer period (in 4ns) */
	*ptr++ = dcb->sync_offset;	/* Transfer period (max. REQ/ACK dist) */
	srb->msg_count += 5;
	srb->state |= SRB_DO_SYNC_NEGO;
}


/* WDTR */
static void build_wdtr(struct AdapterCtlBlk *acb, struct DeviceCtlBlk *dcb,
		struct ScsiReqBlk *srb)
{
	u8 wide = ((dcb->dev_mode & NTC_DO_WIDE_NEGO) &
		   (acb->config & HCC_WIDE_CARD)) ? 1 : 0;
	u8 *ptr = srb->msgout_buf + srb->msg_count;
	if (srb->msg_count > 1) {
		dprintkl(KERN_INFO,
			"build_wdtr: msgout_buf BUSY (%i: %02x %02x)\n",
			srb->msg_count, srb->msgout_buf[0],
			srb->msgout_buf[1]);
		return;
	}
	*ptr++ = MSG_EXTENDED;	/* (01h) */
	*ptr++ = 2;		/* length */
	*ptr++ = EXTENDED_WDTR;	/* (03h) */
	*ptr++ = wide;
	srb->msg_count += 4;
	srb->state |= SRB_DO_WIDE_NEGO;
}


#if 0
/* Timer to work around chip flaw: When selecting and the bus is 
 * busy, we sometimes miss a Selection timeout IRQ */
void selection_timeout_missed(unsigned long ptr);
/* Sets the timer to wake us up */
static void selto_timer(struct AdapterCtlBlk *acb)
{
	if (timer_pending(&acb->selto_timer))
		return;
	acb->selto_timer.function = selection_timeout_missed;
	acb->selto_timer.data = (unsigned long) acb;
	if (time_before
	    (jiffies + HZ, acb->last_reset + HZ / 2))
		acb->selto_timer.expires =
		    acb->last_reset + HZ / 2 + 1;
	else
		acb->selto_timer.expires = jiffies + HZ + 1;
	add_timer(&acb->selto_timer);
}


void selection_timeout_missed(unsigned long ptr)
{
	unsigned long flags;
	struct AdapterCtlBlk *acb = (struct AdapterCtlBlk *)ptr;
	struct ScsiReqBlk *srb;
	dprintkl(KERN_DEBUG, "Chip forgot to produce SelTO IRQ!\n");
	if (!acb->active_dcb || !acb->active_dcb->active_srb) {
		dprintkl(KERN_DEBUG, "... but no cmd pending? Oops!\n");
		return;
	}
	DC395x_LOCK_IO(acb->scsi_host, flags);
	srb = acb->active_dcb->active_srb;
	disconnect(acb);
	DC395x_UNLOCK_IO(acb->scsi_host, flags);
}
#endif


static u8 start_scsi(struct AdapterCtlBlk* acb, struct DeviceCtlBlk* dcb,
		struct ScsiReqBlk* srb)
{
	u16 s_stat2, return_code;
	u8 s_stat, scsicommand, i, identify_message;
	u8 *ptr;
	dprintkdbg(DBG_0, "start_scsi: (0x%p) <%02i-%i> srb=%p\n",
		dcb->target_id, dcb->target_lun, srb);

	srb->tag_number = TAG_NONE;	/* acb->tag_max_num: had error read in eeprom */

	s_stat = DC395x_read8(acb, TRM_S1040_SCSI_SIGNAL);
	s_stat2 = 0;
	s_stat2 = DC395x_read16(acb, TRM_S1040_SCSI_STATUS);
#if 1
	if (s_stat & 0x20 /* s_stat2 & 0x02000 */ ) {
		dprintkdbg(DBG_KG, "start_scsi: (0x%p) BUSY %02x %04x\n",
			s_stat, s_stat2);
		/*
		 * Try anyway?
		 *
		 * We could, BUT: Sometimes the TRM_S1040 misses to produce a Selection
		 * Timeout, a Disconnect or a Reselection IRQ, so we would be screwed!
		 * (This is likely to be a bug in the hardware. Obviously, most people
		 *  only have one initiator per SCSI bus.)
		 * Instead let this fail and have the timer make sure the command is 
		 * tried again after a short time
		 */
		/*selto_timer (acb); */
		return 1;
	}
#endif
	if (acb->active_dcb) {
		dprintkl(KERN_DEBUG, "start_scsi: (0x%p) Attempt to start a"
			"command while another command (0x%p) is active.",
			srb->cmd,
			acb->active_dcb->active_srb ?
			    acb->active_dcb->active_srb->cmd : 0);
		return 1;
	}
	if (DC395x_read16(acb, TRM_S1040_SCSI_STATUS) & SCSIINTERRUPT) {
		dprintkdbg(DBG_KG, "start_scsi: (0x%p) Failed (busy)\n", srb->cmd);
		return 1;
	}
	/* Allow starting of SCSI commands half a second before we allow the mid-level
	 * to queue them again after a reset */
	if (time_before(jiffies, acb->last_reset - HZ / 2)) {
		dprintkdbg(DBG_KG, "start_scsi: Refuse cmds (reset wait)\n");
		return 1;
	}

	/* Flush FIFO */
	clear_fifo(acb, "start_scsi");
	DC395x_write8(acb, TRM_S1040_SCSI_HOSTID, acb->scsi_host->this_id);
	DC395x_write8(acb, TRM_S1040_SCSI_TARGETID, dcb->target_id);
	DC395x_write8(acb, TRM_S1040_SCSI_SYNC, dcb->sync_period);
	DC395x_write8(acb, TRM_S1040_SCSI_OFFSET, dcb->sync_offset);
	srb->scsi_phase = PH_BUS_FREE;	/* initial phase */

	identify_message = dcb->identify_msg;
	/*DC395x_TRM_write8(TRM_S1040_SCSI_IDMSG, identify_message); */
	/* Don't allow disconnection for AUTO_REQSENSE: Cont.All.Cond.! */
	if (srb->flag & AUTO_REQSENSE)
		identify_message &= 0xBF;

	if (((srb->cmd->cmnd[0] == INQUIRY)
	     || (srb->cmd->cmnd[0] == REQUEST_SENSE)
	     || (srb->flag & AUTO_REQSENSE))
	    && (((dcb->sync_mode & WIDE_NEGO_ENABLE)
		 && !(dcb->sync_mode & WIDE_NEGO_DONE))
		|| ((dcb->sync_mode & SYNC_NEGO_ENABLE)
		    && !(dcb->sync_mode & SYNC_NEGO_DONE)))
	    && (dcb->target_lun == 0)) {
		srb->msgout_buf[0] = identify_message;
		srb->msg_count = 1;
		scsicommand = SCMD_SEL_ATNSTOP;
		srb->state = SRB_MSGOUT;
#ifndef SYNC_FIRST
		if (dcb->sync_mode & WIDE_NEGO_ENABLE
		    && dcb->inquiry7 & SCSI_INQ_WBUS16) {
			build_wdtr(acb, dcb, srb);
			goto no_cmd;
		}
#endif
		if (dcb->sync_mode & SYNC_NEGO_ENABLE
		    && dcb->inquiry7 & SCSI_INQ_SYNC) {
			build_sdtr(acb, dcb, srb);
			goto no_cmd;
		}
		if (dcb->sync_mode & WIDE_NEGO_ENABLE
		    && dcb->inquiry7 & SCSI_INQ_WBUS16) {
			build_wdtr(acb, dcb, srb);
			goto no_cmd;
		}
		srb->msg_count = 0;
	}
	/* Send identify message */
	DC395x_write8(acb, TRM_S1040_SCSI_FIFO, identify_message);

	scsicommand = SCMD_SEL_ATN;
	srb->state = SRB_START_;
#ifndef DC395x_NO_TAGQ
	if ((dcb->sync_mode & EN_TAG_QUEUEING)
	    && (identify_message & 0xC0)) {
		/* Send Tag message */
		u32 tag_mask = 1;
		u8 tag_number = 0;
		while (tag_mask & dcb->tag_mask
		       && tag_number < dcb->max_command) {
			tag_mask = tag_mask << 1;
			tag_number++;
		}
		if (tag_number >= dcb->max_command) {
			dprintkl(KERN_WARNING, "start_scsi: (0x%p) "
				"Out of tags target=<%02i-%i>)\n",
				srb->cmd, srb->cmd->device->id,
				(u8)srb->cmd->device->lun);
			srb->state = SRB_READY;
			DC395x_write16(acb, TRM_S1040_SCSI_CONTROL,
				       DO_HWRESELECT);
			return 1;
		}
		/* Send Tag id */
		DC395x_write8(acb, TRM_S1040_SCSI_FIFO, MSG_SIMPLE_QTAG);
		DC395x_write8(acb, TRM_S1040_SCSI_FIFO, tag_number);
		dcb->tag_mask |= tag_mask;
		srb->tag_number = tag_number;
		scsicommand = SCMD_SEL_ATN3;
		srb->state = SRB_START_;
	}
#endif
/*polling:*/
	/* Send CDB ..command block ......... */
	dprintkdbg(DBG_KG, "start_scsi: (0x%p) <%02i-%i> cmnd=0x%02x tag=%i\n",
		srb->cmd, srb->cmd->device->id, (u8)srb->cmd->device->lun,
		srb->cmd->cmnd[0], srb->tag_number);
	if (srb->flag & AUTO_REQSENSE) {
		DC395x_write8(acb, TRM_S1040_SCSI_FIFO, REQUEST_SENSE);
		DC395x_write8(acb, TRM_S1040_SCSI_FIFO, (dcb->target_lun << 5));
		DC395x_write8(acb, TRM_S1040_SCSI_FIFO, 0);
		DC395x_write8(acb, TRM_S1040_SCSI_FIFO, 0);
		DC395x_write8(acb, TRM_S1040_SCSI_FIFO, SCSI_SENSE_BUFFERSIZE);
		DC395x_write8(acb, TRM_S1040_SCSI_FIFO, 0);
	} else {
		ptr = (u8 *)srb->cmd->cmnd;
		for (i = 0; i < srb->cmd->cmd_len; i++)
			DC395x_write8(acb, TRM_S1040_SCSI_FIFO, *ptr++);
	}
      no_cmd:
	DC395x_write16(acb, TRM_S1040_SCSI_CONTROL,
		       DO_HWRESELECT | DO_DATALATCH);
	if (DC395x_read16(acb, TRM_S1040_SCSI_STATUS) & SCSIINTERRUPT) {
		/* 
		 * If start_scsi return 1:
		 * we caught an interrupt (must be reset or reselection ... )
		 * : Let's process it first!
		 */
		dprintkdbg(DBG_0, "start_scsi: (0x%p) <%02i-%i> Failed - busy\n",
			srb->cmd, dcb->target_id, dcb->target_lun);
		srb->state = SRB_READY;
		free_tag(dcb, srb);
		srb->msg_count = 0;
		return_code = 1;
		/* This IRQ should NOT get lost, as we did not acknowledge it */
	} else {
		/* 
		 * If start_scsi returns 0:
		 * we know that the SCSI processor is free
		 */
		srb->scsi_phase = PH_BUS_FREE;	/* initial phase */
		dcb->active_srb = srb;
		acb->active_dcb = dcb;
		return_code = 0;
		/* it's important for atn stop */
		DC395x_write16(acb, TRM_S1040_SCSI_CONTROL,
			       DO_DATALATCH | DO_HWRESELECT);
		/* SCSI command */
		DC395x_write8(acb, TRM_S1040_SCSI_COMMAND, scsicommand);
	}
	return return_code;
}


#define DC395x_ENABLE_MSGOUT \
 DC395x_write16 (acb, TRM_S1040_SCSI_CONTROL, DO_SETATN); \
 srb->state |= SRB_MSGOUT


/* abort command */
static inline void enable_msgout_abort(struct AdapterCtlBlk *acb,
		struct ScsiReqBlk *srb)
{
	srb->msgout_buf[0] = ABORT;
	srb->msg_count = 1;
	DC395x_ENABLE_MSGOUT;
	srb->state &= ~SRB_MSGIN;
	srb->state |= SRB_MSGOUT;
}


/**
 * dc395x_handle_interrupt - Handle an interrupt that has been confirmed to
 *                           have been triggered for this card.
 *
 * @acb:	 a pointer to the adpter control block
 * @scsi_status: the status return when we checked the card
 **/
static void dc395x_handle_interrupt(struct AdapterCtlBlk *acb,
		u16 scsi_status)
{
	struct DeviceCtlBlk *dcb;
	struct ScsiReqBlk *srb;
	u16 phase;
	u8 scsi_intstatus;
	unsigned long flags;
	void (*dc395x_statev)(struct AdapterCtlBlk *, struct ScsiReqBlk *, 
			      u16 *);

	DC395x_LOCK_IO(acb->scsi_host, flags);

	/* This acknowledges the IRQ */
	scsi_intstatus = DC395x_read8(acb, TRM_S1040_SCSI_INTSTATUS);
	if ((scsi_status & 0x2007) == 0x2002)
		dprintkl(KERN_DEBUG,
			"COP after COP completed? %04x\n", scsi_status);
	if (debug_enabled(DBG_KG)) {
		if (scsi_intstatus & INT_SELTIMEOUT)
			dprintkdbg(DBG_KG, "handle_interrupt: Selection timeout\n");
	}
	/*dprintkl(KERN_DEBUG, "handle_interrupt: intstatus = 0x%02x ", scsi_intstatus); */

	if (timer_pending(&acb->selto_timer))
		del_timer(&acb->selto_timer);

	if (scsi_intstatus & (INT_SELTIMEOUT | INT_DISCONNECT)) {
		disconnect(acb);	/* bus free interrupt  */
		goto out_unlock;
	}
	if (scsi_intstatus & INT_RESELECTED) {
		reselect(acb);
		goto out_unlock;
	}
	if (scsi_intstatus & INT_SELECT) {
		dprintkl(KERN_INFO, "Host does not support target mode!\n");
		goto out_unlock;
	}
	if (scsi_intstatus & INT_SCSIRESET) {
		scsi_reset_detect(acb);
		goto out_unlock;
	}
	if (scsi_intstatus & (INT_BUSSERVICE | INT_CMDDONE)) {
		dcb = acb->active_dcb;
		if (!dcb) {
			dprintkl(KERN_DEBUG,
				"Oops: BusService (%04x %02x) w/o ActiveDCB!\n",
				scsi_status, scsi_intstatus);
			goto out_unlock;
		}
		srb = dcb->active_srb;
		if (dcb->flag & ABORT_DEV_) {
			dprintkdbg(DBG_0, "MsgOut Abort Device.....\n");
			enable_msgout_abort(acb, srb);
		}

		/* software sequential machine */
		phase = (u16)srb->scsi_phase;

		/* 
		 * 62037 or 62137
		 * call  dc395x_scsi_phase0[]... "phase entry"
		 * handle every phase before start transfer
		 */
		/* data_out_phase0,	phase:0 */
		/* data_in_phase0,	phase:1 */
		/* command_phase0,	phase:2 */
		/* status_phase0,	phase:3 */
		/* nop0,		phase:4 PH_BUS_FREE .. initial phase */
		/* nop0,		phase:5 PH_BUS_FREE .. initial phase */
		/* msgout_phase0,	phase:6 */
		/* msgin_phase0,	phase:7 */
		dc395x_statev = dc395x_scsi_phase0[phase];
		dc395x_statev(acb, srb, &scsi_status);

		/* 
		 * if there were any exception occurred scsi_status
		 * will be modify to bus free phase new scsi_status
		 * transfer out from ... previous dc395x_statev
		 */
		srb->scsi_phase = scsi_status & PHASEMASK;
		phase = (u16)scsi_status & PHASEMASK;

		/* 
		 * call  dc395x_scsi_phase1[]... "phase entry" handle
		 * every phase to do transfer
		 */
		/* data_out_phase1,	phase:0 */
		/* data_in_phase1,	phase:1 */
		/* command_phase1,	phase:2 */
		/* status_phase1,	phase:3 */
		/* nop1,		phase:4 PH_BUS_FREE .. initial phase */
		/* nop1,		phase:5 PH_BUS_FREE .. initial phase */
		/* msgout_phase1,	phase:6 */
		/* msgin_phase1,	phase:7 */
		dc395x_statev = dc395x_scsi_phase1[phase];
		dc395x_statev(acb, srb, &scsi_status);
	}
      out_unlock:
	DC395x_UNLOCK_IO(acb->scsi_host, flags);
}


static irqreturn_t dc395x_interrupt(int irq, void *dev_id)
{
	struct AdapterCtlBlk *acb = dev_id;
	u16 scsi_status;
	u8 dma_status;
	irqreturn_t handled = IRQ_NONE;

	/*
	 * Check for pending interrupt
	 */
	scsi_status = DC395x_read16(acb, TRM_S1040_SCSI_STATUS);
	dma_status = DC395x_read8(acb, TRM_S1040_DMA_STATUS);
	if (scsi_status & SCSIINTERRUPT) {
		/* interrupt pending - let's process it! */
		dc395x_handle_interrupt(acb, scsi_status);
		handled = IRQ_HANDLED;
	}
	else if (dma_status & 0x20) {
		/* Error from the DMA engine */
		dprintkl(KERN_INFO, "Interrupt from DMA engine: 0x%02x!\n", dma_status);
#if 0
		dprintkl(KERN_INFO, "This means DMA error! Try to handle ...\n");
		if (acb->active_dcb) {
			acb->active_dcb-> flag |= ABORT_DEV_;
			if (acb->active_dcb->active_srb)
				enable_msgout_abort(a…