path: root/drivers/scsi/sim710.c

/*
 * sim710.c - Copyright (C) 1999 Richard Hirst <richard@sleepie.demon.co.uk>
 *
 *----------------------------------------------------------------------------
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by 
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *----------------------------------------------------------------------------
 *
 * MCA card detection code by Trent McNair.
 *
 * Various bits of code in this driver have been copied from 53c7,8xx,c,
 * which is coyright Drew Eckhardt.  The scripts for the SCSI chip are
 * compiled with the script compiler written by Drew.
 *
 * This is a simple driver for the NCR53c710.  More complex drivers
 * for this chip (e.g. 53c7xx.c) require that the scsi chip be able to
 * do DMA block moves between memory and on-chip registers, which can
 * be a problem if those registers are in the I/O address space.  There
 * can also be problems on hardware where the registers are memory
 * mapped, if the design is such that memory-to-memory transfers initiated
 * by the scsi chip cannot access the chip registers.
 *
 * This driver is designed to avoid these problems and is intended to
 * work with any Intel machines using 53c710 chips, including various
 * Compaq and NCR machines.  It was initially written for the Tadpole
 * TP34V VME board which is 68030 based.
 *
 * The driver supports boot-time parameters similar to
 *	sim710=addr:0x9000,irq:15
 * and insmod parameters similar to
 *	sim710="addr:0x9000 irq:15"
 *
 * The complete list of options are:
 *
 * addr:0x9000		Specifies the base I/O port (or address) of the 53C710.
 * irq:15		Specifies the IRQ number used by the 53c710.
 * debug:0xffff		Generates lots of debug output.
 * ignore:0x0a		Makes the driver ignore SCSI IDs 0 and 2.
 * nodisc:0x70		Prevents disconnects from IDs 6, 5 and 4.
 * noneg:0x10		Prevents SDTR negotiation on ID 4.
 *
 * Current limitations:
 *
 * o  Async only
 * o  Severely lacking in error recovery
 * o  Auto detection of IRQs and chip addresses only on MCA architectures
 *
 */

#define LinuxVersionCode(v, p, s) (((v)<<16)+((p)<<8)+(s))

#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/mca.h>
#include <asm/dma.h>
#include <asm/system.h>
#if LINUX_VERSION_CODE >= LinuxVersionCode(2,3,17)
#include <linux/spinlock.h>
#elif LINUX_VERSION_CODE >= LinuxVersionCode(2,1,93)
#include <asm/spinlock.h>
#endif
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/byteorder.h>
#include <linux/blk.h>

#ifdef CONFIG_TP34V_SCSI

#include <asm/tp34vhw.h>
#define MEM_MAPPED

#elif defined(CONFIG_MCA)

#define IO_MAPPED

/*
 * For each known microchannel card using the 53c710 we need a list
 * of possible IRQ and IO settings, as well as their corresponding
 * bit assignment in pos[].  This might get cumbersome if there
 * are more than a few cards (I only know of 2 at this point).
 */

#define MCA_53C710_IDS { 0x01bb, 0x01ba, 0x004f }

/* CARD ID 01BB and 01BA use the same pos values */

#define MCA_01BB_IO_PORTS { 0x0000, 0x0000, 0x0800, 0x0C00, 0x1000, 0x1400, \
			    0x1800, 0x1C00, 0x2000, 0x2400, 0x2800, \
			    0x2C00, 0x3000, 0x3400, 0x3800, 0x3C00, \
			    0x4000, 0x4400, 0x4800, 0x4C00, 0x5000  }

#define MCA_01BB_IRQS { 3, 5, 11, 14 }

/* CARD ID 004f */

#define MCA_004F_IO_PORTS { 0x0000, 0x0200, 0x0300, 0x0400, 0x0500,  0x0600 }

#define MCA_004F_IRQS { 5, 9, 14 }

#else

/* Assume an Intel platform */

#define IO_MAPPED

#endif

#include "scsi.h"
#include "hosts.h"
#include "sim710.h"

#include<linux/stat.h>

#define DEBUG
#undef DEBUG_LIMIT_INTS		/* Define to 10 to hang driver after 10 ints */

/* Debug options available via the "debug:0x1234" parameter		*/

#define DEB_NONE	0x0000	/* Nothing				*/
#define DEB_HALT	0x0001	/* Detailed trace of chip halt funtion	*/
#define DEB_REGS	0x0002	/* All chip register read/writes	*/
#define DEB_SYNC	0x0004	/* Sync/async negotiation		*/
#define DEB_PMM		0x0008	/* Phase mis-match handling		*/
#define DEB_INTS	0x0010	/* General interrupt trace		*/
#define DEB_TOUT	0x0020	/* Selection timeouts			*/
#define DEB_RESUME	0x0040	/* Resume addresses for the script	*/
#define DEB_CMND	0x0080	/* Commands and status returned		*/
#define DEB_FIXUP	0x0100	/* Fixup of scsi addresses		*/
#define DEB_DISC	0x0200	/* Disconnect/reselect handling		*/

#define DEB_ANY		0xffff	/* Any and all debug options		*/

#ifdef DEBUG
#define DEB(m,x) if (sim710_debug & m) x
int sim710_debug = 0;
#else
#define DEB(m,x)
#endif

/* Redefine scsi_done to force renegotiation of (a)sync transfers
 * following any failed command.
 */

#define SCSI_DONE(cmd)	{ \
	DEB(DEB_CMND, printk("scsi%d: Complete %08x\n", \
		host->host_no, cmd->result)); \
	if (cmd->result) \
	    hostdata->negotiate |= (1 << cmd->target); \
	cmd->scsi_done(cmd); \
    }

#ifndef offsetof
#define offsetof(t, m)      ((size_t) (&((t *)0)->m))
#endif


struct proc_dir_entry proc_scsi_sim710 = {
    PROC_SCSI_SIM710, 6, "sim710",
    S_IFDIR | S_IRUGO | S_IXUGO, 2
};

#define STATE_INITIALISED	0
#define STATE_HALTED		1
#define STATE_IDLE		2
#define STATE_BUSY		3
#define STATE_DISABLED		4

#define MAXBOARDS 2	/* Increase this and the sizes of the
			   arrays below, if you need more.. */

#ifdef MODULE

char *sim710;		/* command line passed by insmod */

MODULE_AUTHOR("Richard Hirst");
MODULE_DESCRIPTION("Simple NCR53C710 driver");
MODULE_PARM(sim710, "s");

#endif

static int sim710_errors = 0;	/* Count of error interrupts */
static int sim710_intrs = 0;	/* Count of all interrupts */
static int ignore_ids = 0;	/* Accept all SCSI IDs */
static int opt_nodisc = 0;	/* Allow disconnect on all IDs */
static int opt_noneg = 0;	/* Allow SDTR negotiation on all IDs */

#ifdef CONFIG_TP34V_SCSI

/* Special hardwired case for Tadpole TP34V at the moment, otherwise
 * boot parameters 'sim710=addr:0x8000,irq:15' (for example) must be given.
 */

static int no_of_boards = 2;

static unsigned int bases[MAXBOARDS] = {
	TP34V_SCSI0_BASE, TP34V_SCSI1_BASE
};
static unsigned int irq_vectors[MAXBOARDS] = {
	TP34V_SCSI0_VECTOR, TP34V_SCSI1_VECTOR
};
static unsigned int irq_index[MAXBOARDS] = {
	TP34V_SCSI0_IRQ_INDEX, TP34V_SCSI1_IRQ_INDEX
};

#else

/* All other cases use boot/module params, or auto-detect */

static int no_of_boards = 0;

static unsigned int bases[MAXBOARDS] = {
	0
};
static unsigned int irq_vectors[MAXBOARDS] = {
	0
};

#endif

/* The SCSI Script!!! */

#include "sim710_d.h"

/* Now define offsets in the DSA, as (A_dsa_xxx/4) */

#define DSA_SELECT	(A_dsa_select/4)
#define DSA_MSGOUT	(A_dsa_msgout/4)
#define DSA_CMND	(A_dsa_cmnd/4)
#define DSA_STATUS	(A_dsa_status/4)
#define DSA_MSGIN	(A_dsa_msgin/4)
#define DSA_DATAIN	(A_dsa_datain/4)
#define DSA_DATAOUT	(A_dsa_dataout/4)
#define DSA_SIZE	(A_dsa_size/4)

#define MAX_SG		128	/* Scatter/Gather elements */


#define MAX_MSGOUT	8
#define MAX_MSGIN	8
#define MAX_CMND	12
#define MAX_STATUS	1

struct sim710_hostdata{
    int state;
    Scsi_Cmnd * issue_queue;
    Scsi_Cmnd * running;
    int chip;
    u8 negotiate;
    u8 reselected_identify;
    u8 msgin_buf[MAX_MSGIN];

    struct sim710_target {
	Scsi_Cmnd *cur_cmd;
	u32 resume_offset;
	u32 data_in_jump;
	u32 data_out_jump;
	u32 dsa[DSA_SIZE];		/* SCSI Script DSA area */
	u8  dsa_msgout[MAX_MSGOUT];
	u8  dsa_msgin[MAX_MSGIN];
	u8  dsa_cdb[MAX_CMND];
	u8  dsa_status[MAX_STATUS];
    } target[8];

    u32 script[sizeof(SCRIPT)/4] __attribute__ ((aligned (4)));
};


/* Template to request asynchronous transfers */

static const unsigned char async_message[] = {
    EXTENDED_MESSAGE, 3 /* length */, EXTENDED_SDTR, 0, 0 /* asynchronous */};


static void sim710_intr_handle(int irq, void *dev_id, struct pt_regs *regs);
static void do_sim710_intr_handle(int irq, void *dev_id, struct pt_regs *regs);
static __inline__ void run_process_issue_queue(struct sim710_hostdata *);
static void process_issue_queue (struct sim710_hostdata *, unsigned long flags);
static int full_reset(struct Scsi_Host * host);

/*
 * Function: void sim710_setup(char *str, int *ints)
 */

#ifdef MODULE
#define ARG_SEP ' '
#else
#define ARG_SEP ','
#endif

void
sim710_setup(char *str, int *ints)
{
    char *cur = str;
    char *pc, *pv;
    int val;
    int base;
    int c;

    no_of_boards = 0;
    while (cur != NULL && (pc = strchr(cur, ':')) != NULL) {
	char *pe;

	val = 0;
	pv = pc;
	c = *++pv;

	if (c == 'n')
	    val = 0;
	else if	(c == 'y')
	    val = 1;
	else {
	    base = 0;
	    val = (int) simple_strtoul(pv, &pe, base);
	}
	if (!strncmp(cur, "addr:", 5)) {
	    bases[0] = val;
	    no_of_boards = 1;
	}
	else if	(!strncmp(cur, "irq:", 4))
	    irq_vectors[0] = val;
	else if	(!strncmp(cur, "ignore:", 7))
	    ignore_ids = val;
	else if	(!strncmp(cur, "nodisc:", 7))
	    opt_nodisc = val;
	else if	(!strncmp(cur, "noneg:", 6))
	    opt_noneg = val;
	else if	(!strncmp(cur, "disabled:", 5)) {
	    no_of_boards = -1;
	    return;
	}
#ifdef DEBUG
	else if (!strncmp(cur, "debug:", 6)) {
	    sim710_debug = val;
	}
#endif
	else
	    printk("sim710_setup: unexpected boot option '%.*s' ignored\n", (int)(pc-cur+1), cur);

	if ((cur = strchr(cur, ARG_SEP)) != NULL)
	    ++cur;
    }
}

#if LINUX_VERSION_CODE >= LinuxVersionCode(2,3,13)
#ifndef MODULE
__setup("sim710=", sim710_setup);
#endif
#endif

/*
 * Function: static const char *sbcl_to_phase (int sbcl)
 */

static const char *
sbcl_to_phase (int sbcl) {
    switch (sbcl & SBCL_PHASE_MASK) {
    case SBCL_PHASE_DATAIN:
	return "DATAIN";
    case SBCL_PHASE_DATAOUT:
	return "DATAOUT";
    case SBCL_PHASE_MSGIN:
	return "MSGIN";
    case SBCL_PHASE_MSGOUT:
	return "MSGOUT";
    case SBCL_PHASE_CMDOUT:
	return "CMDOUT";
    case SBCL_PHASE_STATIN:
	return "STATUSIN";
    default:
	return "unknown";
    }
}


/*
 * Function: static void disable (struct Scsi_Host *host)
 */

static void
disable (struct Scsi_Host *host)
{
    struct sim710_hostdata *hostdata = (struct sim710_hostdata *)
	host->hostdata[0];

    hostdata->state = STATE_DISABLED;
    printk (KERN_ALERT "scsi%d : disabled.  Unload and reload\n",
		            host->host_no);
}


/*
 * Function : static int ncr_halt (struct Scsi_Host *host)
 *
 * Purpose : halts the SCSI SCRIPTS(tm) processor on the NCR chip
 *
 * Inputs : host - SCSI chip to halt
 *
 * Returns : 0 on success
 */

static int
ncr_halt (struct Scsi_Host *host)
{
    unsigned long flags;
    unsigned char istat, tmp;
    struct sim710_hostdata *hostdata = (struct sim710_hostdata *)
	host->hostdata[0];
    int stage;

    save_flags(flags);
    cli();
    /* Stage 0 : eat all interrupts
       Stage 1 : set ABORT
       Stage 2 : eat all but abort interrupts
       Stage 3 : eat all interrupts
     */
    for (stage = 0;;) {
	if (stage == 1) {
	    DEB(DEB_HALT, printk("ncr_halt: writing ISTAT_ABRT\n"));
	    NCR_write8(ISTAT_REG, ISTAT_ABRT);
	    ++stage;
	}
	istat = NCR_read8 (ISTAT_REG);
	if (istat & ISTAT_SIP) {
	    DEB(DEB_HALT, printk("ncr_halt: got ISTAT_SIP, istat=%02x\n", istat));
	    tmp = NCR_read8(SSTAT0_REG);
	    DEB(DEB_HALT, printk("ncr_halt: got SSTAT0_REG=%02x\n", tmp));
	} else if (istat & ISTAT_DIP) {
	    DEB(DEB_HALT, printk("ncr_halt: got ISTAT_DIP, istat=%02x\n", istat));
	    tmp = NCR_read8(DSTAT_REG);
	    DEB(DEB_HALT, printk("ncr_halt: got DSTAT_REG=%02x\n", tmp));
	    if (stage == 2) {
		if (tmp & DSTAT_ABRT) {
	    	    DEB(DEB_HALT, printk("ncr_halt: got DSTAT_ABRT, clearing istat\n"));
		    NCR_write8(ISTAT_REG, 0);
		    ++stage;
		} else {
		    printk(KERN_ALERT "scsi%d : could not halt NCR chip\n",
			host->host_no);
		    disable (host);
	    	}
    	    }
	}
	if (!(istat & (ISTAT_SIP|ISTAT_DIP))) {
	    if (stage == 0)
	    	++stage;
	    else if (stage == 3)
		break;
	}
    }
    hostdata->state = STATE_HALTED;
    restore_flags(flags);
    return 0;
}

/*
 * Function : static void sim710_soft_reset (struct Scsi_Host *host)
 *
 * Purpose :  perform a soft reset of the NCR53c7xx chip
 *
 * Inputs : host - pointer to this host adapter's structure
 *
 * Preconditions : sim710_init must have been called for this
 *      host.
 *
 */

static void
sim710_soft_reset (struct Scsi_Host *host)
{
    unsigned long flags;
#ifdef CONFIG_TP34V_SCSI
    struct sim710_hostdata *hostdata = (struct sim710_hostdata *)
	host->hostdata[0];
#endif

    save_flags(flags);
    cli();
#ifdef CONFIG_TP34V_SCSI
    tpvic.loc_icr[irq_index[hostdata->chip]].icr = 0x80;
#endif
    /*
     * Do a soft reset of the chip so that everything is
     * reinitialized to the power-on state.
     *
     * Basically follow the procedure outlined in the NCR53c700
     * data manual under Chapter Six, How to Use, Steps Necessary to
     * Start SCRIPTS, with the exception of actually starting the
     * script and setting up the synchronous transfer gunk.
     */

    /* XXX Should we reset the scsi bus here? */

    NCR_write8(SCNTL1_REG, SCNTL1_RST);		/* Reset the bus */
    udelay(50);
    NCR_write8(SCNTL1_REG, 0);

    udelay(500);

    NCR_write8(ISTAT_REG, ISTAT_10_SRST);	/* Reset the chip */
    udelay(50);
    NCR_write8(ISTAT_REG, 0);

    mdelay(1000);				/* Let devices recover */

    NCR_write8(DCNTL_REG, DCNTL_10_COM | DCNTL_700_CF_3);
    NCR_write8(CTEST7_REG, CTEST7_10_CDIS|CTEST7_STD);
    NCR_write8(DMODE_REG, DMODE_10_BL_8 | DMODE_10_FC2);
    NCR_write8(SCID_REG, 1 << host->this_id);
    NCR_write8(SBCL_REG, 0);
    NCR_write8(SXFER_REG, 0);
    NCR_write8(SCNTL1_REG, SCNTL1_ESR_700);
    NCR_write8(SCNTL0_REG, SCNTL0_EPC | SCNTL0_EPG_700 | SCNTL0_ARB1 |
		SCNTL0_ARB2);

    NCR_write8(DIEN_REG, DIEN_700_BF |
		DIEN_ABRT | DIEN_SSI | DIEN_SIR | DIEN_700_OPC);

    NCR_write8(SIEN_REG_700,
	    SIEN_PAR | SIEN_700_STO | SIEN_RST | SIEN_UDC | SIEN_SGE | SIEN_MA);


#ifdef CONFIG_TP34V_SCSI
    tpvic.loc_icr[irq_index[hostdata->chip]].icr = 0x30 | TP34V_SCSI0n1_IPL;
#endif

    restore_flags(flags);
}


/*
 * Function : static void sim710_driver_init (struct Scsi_Host *host)
 *
 * Purpose : Initialize internal structures, as required on startup, or
 *	after a SCSI bus reset.
 *
 * Inputs : host - pointer to this host adapter's structure
 */

static void
sim710_driver_init (struct Scsi_Host *host)
{
    struct sim710_hostdata *hostdata = (struct sim710_hostdata *)
	host->hostdata[0];
    int i;

    hostdata->running = NULL;
    memcpy (hostdata->script, SCRIPT, sizeof(SCRIPT));
    for (i = 0; i < PATCHES; i++)
	hostdata->script[LABELPATCHES[i]] += virt_to_bus(hostdata->script);
    patch_abs_32 (hostdata->script, 0, reselected_identify, 
    	virt_to_bus((void *)&(hostdata->reselected_identify)));
    patch_abs_32 (hostdata->script, 0, msgin_buf, 
    	virt_to_bus((void *)&(hostdata->msgin_buf[0])));
    hostdata->state = STATE_INITIALISED;
    hostdata->negotiate = 0xff;
}


/* Handle incoming Synchronous data transfer request.  If our negotiate
 * flag is set then this is a response to our request, otherwise it is
 * spurious request from the target.  Don't really expect target initiated
 * SDTRs, because we always negotiate on the first command.  Could still
 * get them though..
 * The chip is currently paused with ACK asserted o the last byte of the
 * SDTR.
 * resa is the resume address if the message is in response to our outgoing
 * SDTR.  Only possible on initial identify.
 * resb is the resume address if the message exchange is initiated by the
 * target.
 */

static u32
handle_sdtr (struct Scsi_Host * host, Scsi_Cmnd * cmd, u32 resa, u32 resb)
{
    struct sim710_hostdata *hostdata = (struct sim710_hostdata *)host->hostdata[0];
    struct sim710_target *targdata = hostdata->target + cmd->target;
    u32 resume_offset;

    if (resa && hostdata->negotiate & (1 << cmd->target)) {
	DEB(DEB_SYNC, printk("scsi%d: Response to host SDTR = %02x %02x\n",
		host->host_no, hostdata->msgin_buf[3], hostdata->msgin_buf[4]));
	/* We always issue an SDTR with the identify, so we must issue
	 * the CDB next.
	 */
	resume_offset = resa;
	hostdata->negotiate &= ~(1 << cmd->target);
    }
    else {
	DEB(DEB_SYNC, printk("scsi%d: Target initiated SDTR = %02x %02x\n",
		host->host_no, hostdata->msgin_buf[3], hostdata->msgin_buf[4]));
	memcpy(targdata->dsa_msgout, async_message, sizeof(async_message));
	targdata->dsa[DSA_MSGOUT] = sizeof(async_message);
	/* I guess the target could do this anytime; we have to send our
	 * response, and then continue (sending the CDB if not already done).
	 */
	resume_offset = resb;
    }
    return resume_offset;
}


/*
 * Function : static int datapath_residual (Scsi_Host *host)
 *
 * Purpose : return residual data count of what's in the chip.
 *
 * Inputs : host - SCSI host
 */

static int
datapath_residual (struct Scsi_Host *host) {
    int count, synchronous, sstat;
    unsigned int ddir;

    count = ((NCR_read8 (DFIFO_REG) & DFIFO_10_BO_MASK) -
	(NCR_read32 (DBC_REG) & DFIFO_10_BO_MASK)) & DFIFO_10_BO_MASK;
    synchronous = NCR_read8 (SXFER_REG) & SXFER_MO_MASK;
    ddir = NCR_read8 (CTEST0_REG_700) & CTEST0_700_DDIR;

    if (ddir) {
    /* Receive */
	if (synchronous) 
	    count += (NCR_read8 (SSTAT2_REG) & SSTAT2_FF_MASK) >> SSTAT2_FF_SHIFT;
	else
	    if (NCR_read8 (SSTAT1_REG) & SSTAT1_ILF)
		++count;
    } else {
    /* Send */
	sstat = NCR_read8 (SSTAT1_REG);
	if (sstat & SSTAT1_OLF)
	    ++count;
	if (synchronous && (sstat & SSTAT1_ORF))
	    ++count;
    }
    return count;
}


static u32
handle_idd (struct Scsi_Host * host, Scsi_Cmnd * cmd)
{
    struct sim710_hostdata *hostdata =
		(struct sim710_hostdata *)host->hostdata[0];
    struct sim710_target *targdata = hostdata->target + cmd->target;
    u32 resume_offset = 0, index;

    index = (u32)((u32 *)(bus_to_virt(NCR_read32(DSP_REG))) - hostdata->script);

    switch (index) {
    case Ent_wait_disc_complete/4 + 2:
	cmd->result = targdata->dsa_status[0];
        SCSI_DONE(cmd);
	targdata->cur_cmd = NULL;
	resume_offset = Ent_reselect;
	break;
    case Ent_wait_disc2/4 + 2:
	/* Disconnect after command - just wait for a reselect */
	targdata->resume_offset = Ent_resume_msgin2a;
	resume_offset = Ent_reselect;
	break;
    case Ent_wait_disc3/4 + 2:
	/* Disconnect after the data phase */
	targdata->resume_offset = Ent_resume_msgin3a;
	resume_offset = Ent_reselect;
	break;
    case Ent_wait_disc1/4 + 2:
	/* Disconnect before command - not expected */
	targdata->resume_offset = Ent_resume_msgin1a;
	resume_offset = Ent_reselect;
	break;
    default:
	printk("scsi%d: Unexpected Illegal Instruction, script[%04x]\n",
		host->host_no, index);
	sim710_errors++;
	/* resume_offset is zero, which will cause host reset */
    }
    return resume_offset;
}


/* Handle a phase mismatch.
 */

static u32
handle_phase_mismatch (struct Scsi_Host * host, Scsi_Cmnd * cmd)
{
    struct sim710_hostdata *hostdata =
		(struct sim710_hostdata *)host->hostdata[0];
    struct sim710_target *targdata = hostdata->target + cmd->target;
    u32 resume_offset = 0, index;
    unsigned char sbcl;

    sbcl = NCR_read8(SBCL_REG) & SBCL_PHASE_MASK;
    index = (u32)((u32 *)(bus_to_virt(NCR_read32(DSP_REG))) - hostdata->script);

    DEB(DEB_PMM, printk("scsi%d: Phase mismatch, phase %s (%x) at script[0x%x]\n",
	host->host_no, sbcl_to_phase(sbcl), sbcl, index));
    DEB(DEB_PMM, print_command(cmd->cmnd));

    if (index == Ent_done_ident/4) {
	/* Sending initial message out - probably rejecting our sync
	 * negotiation request.
	 */
	NCR_write8(SOCL_REG, 0);	/* Negate ATN */
	if (sbcl == SBCL_PHASE_MSGIN)
	    resume_offset = Ent_resume_rej_ident;
	else if (sbcl == SBCL_PHASE_CMDOUT) {
	    /* Some old devices (SQ555) switch to cmdout after the first
	     * byte of an identify message, regardless of whether we
	     * have more bytes to send!
	     */
	    printk("scsi%d: Unexpected switch to CMDOUT during IDENTIFY\n",
		host->host_no);
	    resume_offset = Ent_resume_cmd;
	}
	else {
	    printk("scsi%d: Unexpected phase change to %s on initial msgout\n",
		host->host_no, sbcl_to_phase(sbcl));
	    /* resume_offset is zero, which will cause a host reset */
	}
	hostdata->negotiate &= ~(1 << cmd->target);
    }
    else if (index > Ent_patch_input_data/4 &&
		index < Ent_patch_output_data/4) {
	/* DataIn transfer phase */
	u32 sg_id, oaddr, olen, naddr, nlen;
	int residual;

	sg_id = (index - Ent_patch_input_data/4 - 4) / 2;
	targdata->data_in_jump = hostdata->script[Ent_patch_input_data/4+1] =
		virt_to_bus(hostdata->script + Ent_patch_input_data/4 + sg_id * 2 + 2);
	olen  = targdata->dsa[DSA_DATAIN + sg_id * 2];
	oaddr = targdata->dsa[DSA_DATAIN + sg_id * 2 + 1];
	residual = datapath_residual (host);
	if (residual)
	    printk("scsi%d: Residual count %d on DataIn - NOT expected!!!",
		host->host_no, residual);
	naddr = NCR_read32(DNAD_REG) - residual;
	nlen  = (NCR_read32(DBC_REG) & 0x00ffffff) + residual;
	DEB(DEB_PMM, printk("scsi%d: DIN sg %d, old %08x/%08x, new %08x/%08x (%d)\n",
		host->host_no, sg_id, oaddr, olen, naddr, nlen, residual));
	if (oaddr+olen != naddr+nlen) {
	    printk("scsi%d: PMM DIN counts error: 0x%x + 0x%x != 0x%x + 0x%x",
		host->host_no, oaddr, olen, naddr, nlen);
	}
	else {
	    targdata->dsa[DSA_DATAIN + sg_id * 2]     = nlen;
	    targdata->dsa[DSA_DATAIN + sg_id * 2 + 1] = naddr;
	    resume_offset = Ent_resume_pmm;
	}
    }
    else if (index > Ent_patch_output_data/4 &&
		index <= Ent_end_data_trans/4) {
	/* Dataout transfer phase */
	u32 sg_id, oaddr, olen, naddr, nlen;
	int residual;

	sg_id = (index - Ent_patch_output_data/4 - 4) / 2;
	targdata->data_out_jump = hostdata->script[Ent_patch_output_data/4+1] =
		virt_to_bus(hostdata->script + Ent_patch_output_data/4 + sg_id * 2 + 2);
	olen  = targdata->dsa[DSA_DATAOUT + sg_id * 2];
	oaddr = targdata->dsa[DSA_DATAOUT + sg_id * 2 + 1];
	residual = datapath_residual (host);
	naddr = NCR_read32(DNAD_REG) - residual;
	nlen  = (NCR_read32(DBC_REG) & 0x00ffffff) + residual;
	DEB(DEB_PMM, printk("scsi%d: DOUT sg %d, old %08x/%08x, new %08x/%08x (%d)\n",
		host->host_no, sg_id, oaddr, olen, naddr, nlen, residual));
	if (oaddr+olen != naddr+nlen) {
	    printk("scsi%d: PMM DOUT counts error: 0x%x + 0x%x != 0x%x + 0x%x",
		host->host_no, oaddr, olen, naddr, nlen);
	}
	else {
	    targdata->dsa[DSA_DATAOUT + sg_id * 2]     = nlen;
	    targdata->dsa[DSA_DATAOUT + sg_id * 2 + 1] = naddr;
	    resume_offset = Ent_resume_pmm;
	}
    }
    else {
	printk("scsi%d: Unexpected phase change to %s at index 0x%x\n",
		host->host_no, sbcl_to_phase(sbcl), index);
	/* resume_offset is zero, which will cause a host reset */
    }
    /* Flush DMA FIFO */
    NCR_write8 (CTEST8_REG, CTEST8_10_CLF);
    while (NCR_read8 (CTEST8_REG) & CTEST8_10_CLF);

    return resume_offset;
}


static u32
handle_script_int(struct Scsi_Host * host, Scsi_Cmnd * cmd)
{
    struct sim710_hostdata *hostdata =
		(struct sim710_hostdata *)host->hostdata[0];
    struct sim710_target *targdata = hostdata->target + cmd->target;
    u32 dsps, resume_offset = 0;
    unsigned char sbcl;

    dsps = NCR_read32(DSPS_REG);

    switch (dsps) {
    case A_int_cmd_complete:
	cmd->result = targdata->dsa_status[0];
        SCSI_DONE(cmd);
	targdata->cur_cmd = NULL;
	resume_offset = Ent_reselect;
	break;
    case A_int_msg_sdtr1:
	resume_offset = handle_sdtr(host, cmd,
		Ent_resume_msgin1a, Ent_resume_msgin1b);
	break;
    case A_int_msg_sdtr2:
	resume_offset = handle_sdtr(host, cmd, 0, Ent_resume_msgin2b);
	break;
    case A_int_msg_sdtr3:
	resume_offset = handle_sdtr(host, cmd, 0, Ent_resume_msgin3b);
	break;
    case A_int_disc1:
	/* Disconnect before command - not expected */
	targdata->resume_offset = Ent_resume_msgin1a;
	resume_offset = Ent_reselect;
	break;
    case A_int_disc2:
	/* Disconnect after command - just wait for a reselect */
	targdata->resume_offset = Ent_resume_msgin2a;
	resume_offset = Ent_reselect;
	break;
    case A_int_disc3:
	/* Disconnect after the data phase */
	targdata->resume_offset = Ent_resume_msgin3a;
	resume_offset = Ent_reselect;
	break;
    case A_int_reselected:
	hostdata->script[Ent_patch_output_data/4+1] = targdata->data_out_jump;
	hostdata->script[Ent_patch_input_data/4+1] = targdata->data_in_jump;
	NCR_write32(DSA_REG, virt_to_bus(targdata->dsa));
	resume_offset = targdata->resume_offset;
	break;
    case A_int_data_bad_phase:
	sbcl = NCR_read8(SBCL_REG) & SBCL_PHASE_MASK;
	printk("scsi%d: int_data_bad_phase, phase %s (%x)\n",
		host->host_no, sbcl_to_phase(sbcl), sbcl);
	break;
    case A_int_bad_extmsg1a:
    case A_int_bad_extmsg1b:
    case A_int_bad_extmsg2a:
    case A_int_bad_extmsg2b:
    case A_int_bad_extmsg3a:
    case A_int_bad_extmsg3b:
    case A_int_bad_msg1:
    case A_int_bad_msg2:
    case A_int_bad_msg3:
    case A_int_cmd_bad_phase:
    case A_int_no_msgout1:
    case A_int_no_msgout2:
    case A_int_no_msgout3:
    case A_int_not_cmd_complete:
    case A_int_sel_no_ident:
    case A_int_sel_not_cmd:
    case A_int_status_not_msgin:
    case A_int_resel_not_msgin:
    case A_int_selected:
    case A_int_not_rej:
    default:
	sbcl = NCR_read8(SBCL_REG) & SBCL_PHASE_MASK;
	printk("scsi%d: Unimplemented script interrupt: %08x, phase %s\n",
		host->host_no, dsps, sbcl_to_phase(sbcl));
	sim710_errors++;
	/* resume_offset is zero, which will cause a host reset */
    }
    return resume_offset;
}


/* A quick wrapper for sim710_intr_handle to grab the spin lock */

static void
do_sim710_intr_handle(int irq, void *dev_id, struct pt_regs *regs)
{
    unsigned long flags;

    spin_lock_irqsave(&io_request_lock, flags);
    sim710_intr_handle(irq, dev_id, regs);
    spin_unlock_irqrestore(&io_request_lock, flags);
}


/* A "high" level interrupt handler */

static void
sim710_intr_handle(int irq, void *dev_id, struct pt_regs *regs)
{
    unsigned int flags;
    struct Scsi_Host * host = (struct Scsi_Host *)dev_id;
    struct sim710_hostdata *hostdata = (struct sim710_hostdata *)host->hostdata[0];
    Scsi_Cmnd * cmd;
    unsigned char istat, dstat;
    unsigned char sstat0;
    u32 dsps, resume_offset = 0;

    save_flags(flags);
    cli();
    sim710_intrs++;
    while ((istat = NCR_read8(ISTAT_REG)) & (ISTAT_SIP|ISTAT_DIP)) {
	dsps = NCR_read32(DSPS_REG);
	hostdata->state = STATE_HALTED;
	sstat0 = dstat = 0;
	if (istat & ISTAT_SIP) {
	    sstat0 = NCR_read8(SSTAT0_REG);
	}
	if (istat & ISTAT_DIP) {
	    udelay(10);		/* Some comment somewhere about 10cycles
				 * between accesses to sstat0 and dstat ??? */
	    dstat = NCR_read8(DSTAT_REG);
	}
	DEB(DEB_INTS, printk("scsi%d: Int %d, istat %02x, sstat0 %02x "
		"dstat %02x, dsp [%04x], scratch %02x\n",
	    host->host_no, sim710_intrs, istat, sstat0, dstat,
	    (u32 *)(bus_to_virt(NCR_read32(DSP_REG))) - hostdata->script,
	    NCR_read32(SCRATCH_REG)));
	if ((dstat & DSTAT_SIR) && dsps == A_int_reselected) {
	    /* Reselected.  Identify the target from LCRC_REG, and
	     * update current command.  If we were trying to select
	     * a device, then that command needs to go back on the
	     * issue_queue for later.
	     */
	    unsigned char lcrc = NCR_read8(LCRC_REG_10);
	    int id = 0;

	    if (!(lcrc & 0x7f)) {
		printk("scsi%d: Reselected with LCRC = %02x\n",
			host->host_no, lcrc);
		cmd = NULL;
	    }
	    else {
		while (!(lcrc & 1)) {
		    id++;
		    lcrc >>= 1;
		}
		DEB(DEB_DISC, printk("scsi%d: Reselected by ID %d\n",
			host->host_no, id));
		if (hostdata->running) {
		    /* Clear SIGP */
		    (void)NCR_read8(CTEST2_REG_700);

		    DEB(DEB_DISC, printk("scsi%d: Select of %d interrupted "
				"by reselect from %d (%p)\n",
				host->host_no, hostdata->running->target,
				id, hostdata->target[id].cur_cmd));
		    cmd = hostdata->running;
		    hostdata->target[cmd->target].cur_cmd = NULL;
		    cmd->SCp.ptr = (unsigned char *) hostdata->issue_queue;
		    hostdata->issue_queue = cmd;
		}
		cmd = hostdata->running = hostdata->target[id].cur_cmd;
	    }
	}
	else
	    cmd = hostdata->running;

	if (!cmd) {
	    printk("scsi%d: No active command!\n", host->host_no);
	    printk("scsi%d: Int %d, istat %02x, sstat0 %02x "
		"dstat %02x, dsp [%04x], scratch %02x, dsps %08x\n",
		host->host_no, sim710_intrs, istat, sstat0, dstat,
		(u32 *)(bus_to_virt(NCR_read32(DSP_REG))) - hostdata->script,
		NCR_read32(SCRATCH_REG), dsps);
	    /* resume_offset is zero, which will cause a host reset */
	}
	else if (sstat0 & SSTAT0_700_STO) {
	    DEB(DEB_TOUT, printk("scsi%d: Selection timeout\n", host->host_no));
	    cmd->result = DID_NO_CONNECT << 16;
	    SCSI_DONE(cmd);
	    hostdata->target[cmd->target].cur_cmd = NULL;
	    resume_offset = Ent_reselect;
	}
	else if (dstat & DSTAT_SIR)
	    resume_offset = handle_script_int(host, cmd);
	else if (sstat0 & SSTAT0_MA) {
	    resume_offset = handle_phase_mismatch(host, cmd);
	}
	else if (sstat0 & (SSTAT0_MA|SSTAT0_SGE|SSTAT0_UDC|SSTAT0_RST|SSTAT0_PAR)) {
	    printk("scsi%d: Serious error, sstat0 = %02x\n", host->host_no,
			    sstat0);
	    sim710_errors++;
	    /* resume_offset is zero, which will cause a host reset */
	}
	else if (dstat & (DSTAT_BF|DSTAT_ABRT|DSTAT_SSI|DSTAT_WTD)) {
	    printk("scsi%d: Serious error, dstat = %02x\n", host->host_no,
			    dstat);
	    sim710_errors++;
	    /* resume_offset is zero, which will cause a host reset */
	}
	else if (dstat & DSTAT_IID) {
	    /* This can be due to a quick reselect while doing a WAIT
	     * DISCONNECT.
	     */
	    resume_offset = handle_idd(host, cmd);
	}
	else {
	    sim710_errors++;
	    printk("scsi%d: Spurious interrupt!\n", host->host_no);
	    /* resume_offset is zero, which will cause a host reset */
	}
    }

    if (resume_offset) {
	if (resume_offset == Ent_reselect) {
	    hostdata->running = NULL;
	    hostdata->state = STATE_IDLE;
	}
	else
	    hostdata->state = STATE_BUSY;
	DEB(DEB_RESUME, printk("scsi%d: Resuming at script[0x%x]\n",
		host->host_no, resume_offset/4));
#ifdef DEBUG_LIMIT_INTS
	if (sim710_intrs < DEBUG_LIMIT_INTS)
#endif
	NCR_write32(DSP_REG, virt_to_bus(hostdata->script+resume_offset/4));
	if (resume_offset == Ent_reselect)
	    run_process_issue_queue(hostdata);
    }
    else {
	printk("scsi%d: Failed to handle interrupt.  Failing commands "
		"and resetting SCSI bus and chip\n", host->host_no);
	mdelay(4000);		/* Give chance to read screen!! */
	full_reset(host);
    }

    restore_flags(flags);
}


static void
run_command (struct sim710_hostdata *hostdata, Scsi_Cmnd *cmd)
{
    struct Scsi_Host *host = cmd->host;
    struct sim710_target *targdata = hostdata->target + cmd->target;
    int i, datain, dataout, sg_start;
    u32 *dip, *dop, dsa;

    DEB(DEB_CMND, printk("scsi%d: id%d starting ", host->host_no,
		cmd->target));
    DEB(DEB_CMND, print_command(cmd->cmnd));

    switch (cmd->cmnd[0]) {
    case INQUIRY:
    case MODE_SENSE:
    case READ_6:
    case READ_10:
    case READ_CAPACITY:
    case REQUEST_SENSE:
    case READ_BLOCK_LIMITS:
    case READ_TOC:
        datain = 1;
	dataout = 0;
        break;
    case MODE_SELECT:
    case WRITE_6:
    case WRITE_10:
        datain = 0;
        dataout = 1;
        break;
    case TEST_UNIT_READY:
    case ALLOW_MEDIUM_REMOVAL:
    case START_STOP:
        datain = dataout = 0;
        break;
    default:
        datain = dataout = 1;
    }

    memcpy(targdata->dsa_cdb, cmd->cmnd, MAX_CMND);

    targdata->dsa_msgout[0] =
		IDENTIFY((opt_nodisc & (1<<cmd->target)) ? 0 : 1 ,0);
    if (hostdata->negotiate & (1 << cmd->target)) {
	if (opt_noneg & (1 << cmd->target)) {
	    hostdata->negotiate ^= (1 << cmd->target);
	    targdata->dsa[DSA_MSGOUT] = 1;
	}
	else {
	    DEB(DEB_SYNC, printk("scsi%d: Negotiating async transfers "
		"for ID %d\n",
		host->host_no, cmd->target));
	    memcpy(targdata->dsa_msgout+1, async_message, sizeof(async_message));
	    targdata->dsa[DSA_MSGOUT] = sizeof(async_message) + 1;
	}
    }
    else
	targdata->dsa[DSA_MSGOUT] = 1;

    targdata->dsa_msgin[0] = 0xff;
    targdata->dsa_status[0] = 0xff;

    targdata->dsa[DSA_SELECT]		= (1 << cmd->target) << 16;
    targdata->dsa[DSA_MSGOUT+1]		= virt_to_bus(targdata->dsa_msgout);
    targdata->dsa[DSA_CMND]		= cmd->cmd_len;
    targdata->dsa[DSA_CMND+1]		= virt_to_bus(targdata->dsa_cdb);
    targdata->dsa[DSA_STATUS]		= 1;
    targdata->dsa[DSA_STATUS+1]		= virt_to_bus(targdata->dsa_status);
    targdata->dsa[DSA_MSGIN]		= 1;
    targdata->dsa[DSA_MSGIN+1]		= virt_to_bus(targdata->dsa_msgin);

    sg_start = (MAX_SG - (cmd->use_sg ? cmd->use_sg : 1)) * 2;
    dip = targdata->dsa + DSA_DATAIN + sg_start;
    dop = targdata->dsa + DSA_DATAOUT + sg_start;

    for (i = 0; cmd->use_sg ? (i < cmd->use_sg) : !i; i++) {
	u32 vbuf = cmd->use_sg ?
		(u32)(((struct scatterlist *)cmd->buffer)[i].address) :
		(u32)(cmd->request_buffer);
	u32 bbuf = virt_to_bus((void *)vbuf);
	u32 cnt = cmd->use_sg ?
		((struct scatterlist *)cmd->buffer)[i].length :
		cmd->request_bufflen;

	if (datain) {
#ifdef CONFIG_TP34V_SCSI
	    cache_clear(virt_to_phys((void *)vbuf), cnt);
#endif
	    *dip++	= cnt;
	    *dip++	= bbuf;
	}
	if (dataout) {
#ifdef CONFIG_TP34V_SCSI
	    cache_push(virt_to_phys((void *)vbuf), cnt);
#endif
	    *dop++	= cnt;
	    *dop++	= bbuf;
	}
    }
    targdata->data_out_jump = hostdata->script[Ent_patch_output_data/4+1] =
	virt_to_bus(hostdata->script + Ent_patch_output_data/4 + sg_start + 2);
    targdata->data_in_jump = hostdata->script[Ent_patch_input_data/4+1] =
	virt_to_bus(hostdata->script + Ent_patch_input_data/4 + sg_start + 2);

    for (i = 0, dsa = virt_to_bus(targdata->dsa); i < 4; i++) {
	u32 v = hostdata->script[Ent_patch_new_dsa/4 + i * 2];

	v &= ~0x0000ff00;
	v |= (dsa & 0xff) << 8;
	hostdata->script[Ent_patch_new_dsa/4 + i * 2] = v;
	dsa >>= 8;
    }
    hostdata->running = targdata->cur_cmd = cmd;
    hostdata->state = STATE_BUSY;

    NCR_write8(ISTAT_REG, ISTAT_10_SIGP);
}


static volatile int process_issue_queue_running = 0;
 
static __inline__ void 
run_process_issue_queue(struct sim710_hostdata *hostdata)
{
    unsigned long flags;
    save_flags (flags);
    cli();
    if (!process_issue_queue_running) {
	process_issue_queue_running = 1;
	process_issue_queue(hostdata, flags);
	/*
	 * process_issue_queue_running is cleared in process_issue_queue
	 * once it can't do more work, and process_issue_queue exits with
	 * interrupts disabled.
	 */
    }
    restore_flags (flags);
}


/*
 * Function : process_issue_queue (hostdata, flags)
 *
 * Purpose : Start next command for any idle target.
 * 
 * NOTE : process_issue_queue exits with interrupts *disabled*, so the 
 *	caller must reenable them if it desires.
 * 
 * NOTE : process_issue_queue should be called from both 
 *	sim710_queue_command() and from the interrupt handler 
 *	after command completion.
 */

static void 
process_issue_queue (struct sim710_hostdata *hostdata, unsigned long flags)
{
    Scsi_Cmnd *tmp, *prev;
    int done;

    /*
     * We run (with interrupts disabled) until we're sure that none of 
     * the host adapters have anything that can be done, at which point 
     * we set process_issue_queue_running to 0 and exit.
     *
     * Interrupts are enabled before doing various other internal 
     * instructions, after we've decided that we need to run through
     * the loop again.
     *
     */

    do {
	cli(); /* Freeze request queues */
	done = 1;
	if (hostdata->issue_queue) {
	    if (hostdata->state == STATE_DISABLED) {
		tmp = (Scsi_Cmnd *) hostdata->issue_queue;
		hostdata->issue_queue = (Scsi_Cmnd *) tmp->SCp.ptr;
		tmp->result = (DID_BAD_TARGET << 16);
		tmp->scsi_done (tmp);
		done = 0;
	    }
	    else if (hostdata->state == STATE_IDLE) {
		for (tmp = hostdata->issue_queue, prev = NULL; tmp;
				prev = tmp, tmp = (Scsi_Cmnd *) tmp->SCp.ptr) {
		    if (hostdata->target[tmp->target].cur_cmd == NULL) {
			if (prev)
			    prev->SCp.ptr = tmp->SCp.ptr;
			else
			    hostdata->issue_queue = (Scsi_Cmnd *) tmp->SCp.ptr;
			tmp->SCp.ptr = NULL;
			run_command (hostdata, tmp);
			done = 0;
		    } /* if target/lun is not busy */
		} /* scan issue queue for work */
	    } /* host is idle */
	} /* if hostdata->issue_queue */
	if (!done)
	    restore_flags (flags);
    } while (!done);
    process_issue_queue_running = 0;
}


int
sim710_queuecommand(Scsi_Cmnd * cmd, void (*done)(Scsi_Cmnd *))
{
    struct Scsi_Host *host = cmd->host;
    struct sim710_hostdata *hostdata = (struct sim710_hostdata *)host->hostdata[0];
    Scsi_Cmnd *tmp;
    unsigned long flags;

    if (cmd->lun) {
	/* Silently ignore luns other than zero! */
	cmd->result = (DID_BAD_TARGET << 16);
	done(cmd);
	return 0;
    }

    DEB(DEB_CMND, printk("scsi%d: id%d queuing ", host->host_no,
		cmd->target));
    DEB(DEB_CMND, print_command(cmd->cmnd));

    cmd->scsi_done = done;
    cmd->host_scribble = NULL;
    cmd->SCp.ptr = NULL;
    cmd->SCp.buffer = NULL;

    save_flags(flags);
    cli();

    if (ignore_ids & (1 << cmd->target)) {
	printk("scsi%d: ignoring target %d\n", host->host_no, cmd->target);
	cmd->result = (DID_BAD_TARGET << 16);
	done(cmd);
	restore_flags (flags);
	return 0;
    }
#ifdef DEBUG_LIMIT_INTS
    if (sim710_intrs > DEBUG_LIMIT_INTS) {
	cmd->result = (DID_BAD_TARGET << 16);
	done(cmd);
	restore_flags (flags);
	return 0;
    }
#endif
    if (cmd->use_sg > MAX_SG)
	panic ("cmd->use_sg = %d\n", cmd->use_sg);

    if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
        cmd->SCp.ptr = (unsigned char *) hostdata->issue_queue;
        hostdata->issue_queue = cmd;
    } else {
        for (tmp = hostdata->issue_queue; tmp->SCp.ptr;
                tmp = (Scsi_Cmnd *) tmp->SCp.ptr);
        tmp->SCp.ptr = (unsigned char *) cmd;
    }
    restore_flags (flags);
    run_process_issue_queue(hostdata);
    return 0;
}


int
sim710_detect(Scsi_Host_Template * tpnt)
{
    unsigned char irq_vector;
    unsigned char scsi_id;
    unsigned int base_addr;
    struct Scsi_Host * host = NULL;
    struct sim710_hostdata *hostdata;
    int chips = 0;
    int indx;
    int revision;
    int order, size;

#ifdef MODULE
    if (sim710)
	sim710_setup(sim710, (int *)0);
#endif

    if (no_of_boards < 0) {
	printk("sim710: NCR53C710 driver disabled\n");
	return 0;
    }

#ifdef CONFIG_MCA
    /* If board details have been specified via boot/module parameters,
     * then don't bother probing.
     */
    if (no_of_boards == 0) {
	int slot;
	int pos[3];
	int mca_53c710_ids[] = MCA_53C710_IDS;
	int *id_to_check = mca_53c710_ids;
	static int io_004f_by_pos[] = MCA_004F_IO_PORTS;
	static int irq_004f_by_pos[] = MCA_004F_IRQS;
	static int io_01bb_by_pos[] = MCA_01BB_IO_PORTS;
	static int irq_01bb_by_pos[] = MCA_01BB_IRQS;

	while ( *id_to_check && no_of_boards < MAXBOARDS) {
	    if (!MCA_bus)
		return 0;

	    if ((slot = mca_find_adapter(*id_to_check, 0)) != MCA_NOTFOUND) {

		pos[0] = mca_read_stored_pos(slot, 2);
		pos[1] = mca_read_stored_pos(slot, 3);
		pos[2] = mca_read_stored_pos(slot, 4);

		/*
		 * 01BB & 01BA port base by bits 7,6,5,4,3,2 in pos[2]
		 *
		 *    000000  <disabled>   001010  0x2800
		 *    000001  <invalid>    001011  0x2C00
		 *    000010  0x0800       001100  0x3000
		 *    000011  0x0C00       001101  0x3400
		 *    000100  0x1000       001110  0x3800
		 *    000101  0x1400       001111  0x3C00
		 *    000110  0x1800       010000  0x4000
		 *    000111  0x1C00       010001  0x4400
		 *    001000  0x2000       010010  0x4800
		 *    001001  0x2400       010011  0x4C00
		 *                         010100  0x5000
		 *
		 * 00F4 port base by bits 3,2,1 in pos[0]
		 *
		 *    000  <disabled>      001    0x200
		 *    010  0x300           011    0x400
		 *    100  0x500           101    0x600
		 *
		 * 01BB & 01BA IRQ is specified in pos[0] bits 7 and 6:
		 *
		 *    00   3               10   11
		 *    01   5               11   14
		 *
		 * 00F4 IRQ specified by bits 6,5,4 in pos[0]
		 *
		 *    100   5              101    9
		 *    110   14
		 */

		if ( *id_to_check == 0x01bb || *id_to_check == 0x01ba ) {
		    bases[no_of_boards] = io_01bb_by_pos[(pos[2] & 0xFC) >> 2];
		    irq_vectors[no_of_boards] =
				irq_01bb_by_pos[((pos[0] & 0xC0) >> 6)];
		    if (bases[no_of_boards] == 0x0000)
			printk("sim710: NCR53C710 Adapter ID 0x01bb is disabled.\n");
		    else {
			no_of_boards++;
			if ( *id_to_check == 0x01bb )
			    mca_set_adapter_name( slot,
				    "NCR 3360/3430 SCSI SubSystem" );
			else
			    mca_set_adapter_name(slot,
				    "NCR Dual SIOP SCSI Host Adapter Board");
		    }
		}
		else if ( *id_to_check == 0x004f ) {
		    bases[no_of_boards] = io_004f_by_pos[((pos[0] & 0x0E) >> 1)];
		    irq_vectors[no_of_boards] =
				irq_004f_by_pos[((pos[0] & 0x70) >> 4) - 4];
		    if (bases[no_of_boards] == 0x0000)
			printk("sim710: NCR53C710 Adapter ID 0x004f is disabled.\n");
		    else {
			no_of_boards++;
			mca_set_adapter_name(slot,
				"NCR 53c710 SCSI Host Adapter Board");
		    }
		}
	    }
	    id_to_check++;
	}
    }
#endif

    if (!no_of_boards) {
       printk("sim710: No NCR53C710 adapter found.\n");
       return 0;
    }

    size = sizeof(struct sim710_hostdata);
    order = 0;
    while (size > (PAGE_SIZE << order))
	order++;
    size = PAGE_SIZE << order;

    DEB(DEB_ANY, printk("sim710: hostdata %d bytes, size %d, order %d\n",
	sizeof(struct sim710_hostdata), size, order));

    tpnt->proc_dir = &proc_scsi_sim710;

    for(indx = 0; indx < no_of_boards; indx++) {
	host = scsi_register(tpnt, 4);
	host->hostdata[0] = __get_free_pages(GFP_ATOMIC, order);
	if (host->hostdata[0] == 0)
	    panic ("sim710: Couldn't get hostdata memory");
	hostdata = (struct sim710_hostdata *)host->hostdata[0];
	memset(hostdata, 0, size);
#ifdef CONFIG_TP34V_SCSI
	cache_push(virt_to_phys(hostdata), size);
	cache_clear(virt_to_phys(hostdata), size);
	kernel_set_cachemode((void *)hostdata,size,IOMAP_NOCACHE_SER);
#endif
	scsi_id = 7;
	base_addr = bases[indx];
	irq_vector = irq_vectors[indx];
	printk("sim710: Configuring Sim710 (SCSI-ID %d) at %x, IRQ %d\n",
	    		scsi_id, base_addr, irq_vector);
	DEB(DEB_ANY, printk("sim710: hostdata = %p (%d bytes), dsa0 = %p\n",
			hostdata, sizeof(struct sim710_hostdata),
			 hostdata->target[0].dsa));
	hostdata->chip = indx;
	host->irq = irq_vector;
	host->this_id = scsi_id;
	host->unique_id = base_addr;
	host->base = (char *)base_addr;

	ncr_halt(host);

	revision = (NCR_read8(CTEST8_REG) & 0xF0) >> 4;
	printk("scsi%d: Revision 0x%x\n",host->host_no,revision);

	sim710_soft_reset(host);

	sim710_driver_init(host);

#ifdef CONFIG_TP34V_SCSI
	if (request_irq(irq_vector,do_sim710_intr_handle, 0, "sim710", host))
#else
	if (request_irq(irq_vector,do_sim710_intr_handle, SA_INTERRUPT, "sim710", host))
#endif
	{
	    printk("scsi%d : IRQ%d not free, detaching\n",
	    		host->host_no, host->irq);

	    scsi_unregister (host);
	}
	else {
#ifdef IO_MAPPED
	    request_region((u32)host->base, 64, "sim710");
#endif
	    chips++;
	}
	NCR_write32(DSP_REG, virt_to_bus(hostdata->script+Ent_reselect/4));
	hostdata->state = STATE_IDLE;
    }
    return chips;
}

int
sim710_abort(Scsi_Cmnd * cmd)
{
    struct Scsi_Host * host = cmd->host;

    printk("scsi%d: Unable to abort command for target %d\n",
	   host->host_no, cmd->target);
    return FAILED;
}

/*
 * This is a device reset.  Need to select and send a Bus Device Reset msg.
 */

int
sim710_dev_reset(Scsi_Cmnd * SCpnt)
{
    struct Scsi_Host * host = SCpnt->host;

    printk("scsi%d: Unable to send Bus Device Reset for target %d\n",
	   host->host_no, SCpnt->target);
    return FAILED;
}

/*
 * This is bus reset.  We need to reset the bus and fail any active commands.
 */

int
sim710_bus_reset(Scsi_Cmnd * SCpnt)
{
    struct Scsi_Host * host = SCpnt->host;

    printk("scsi%d: Unable to do SCSI bus reset\n", host->host_no);
    return FAILED;
}

static int
full_reset(struct Scsi_Host * host)
{
    struct sim710_hostdata *hostdata = (struct sim710_hostdata *)
	    host->hostdata[0];
    int target;
    Scsi_Cmnd *cmd;

    ncr_halt(host);
    printk("scsi%d: dsp = %08x (script[0x%04x]), scratch = %08x\n",
	host->host_no, NCR_read32(DSP_REG),
	((u32)bus_to_virt(NCR_read32(DSP_REG)) - (u32)hostdata->script)/4,
	NCR_read32(SCRATCH_REG));

    for (target = 0; target < 7; target++) {
	if ((cmd = hostdata->target[target].cur_cmd)) {
	    printk("scsi%d: Failing command for ID%d\n",
			host->host_no, target);
	    cmd->result = DID_RESET << 16;
	    cmd->scsi_done(cmd);
	    hostdata->target[target].cur_cmd = NULL;
	}
    }

    sim710_soft_reset(host);
    sim710_driver_init(host);

    NCR_write32(DSP_REG, virt_to_bus(hostdata->script+Ent_reselect/4));
    hostdata->state = STATE_IDLE;

    run_process_issue_queue(hostdata);

    return SUCCESS;
}

/*
 * This is host reset.  We need to reset the chip and the bus.
 */

int
sim710_host_reset(Scsi_Cmnd * SCpnt)
{
    struct Scsi_Host * host = SCpnt->host;

    printk("scsi%d: >>>>>>>>>>>> Host reset <<<<<<<<<<<<\n", host->host_no);

    return full_reset(host);
}

#ifdef MODULE

int
sim710_release(struct Scsi_Host *host)
{
    free_irq(host->irq, host);
#ifdef IO_MAPPED
    release_region((u32)host->base, 64);
#endif
    return 1;
}

Scsi_Host_Template driver_template = SIM710_SCSI;

#include "scsi_module.c"
#endif