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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0-or-later
 
 /* NCR (or Symbios) 53c700 and 53c700-66 Driver
  *
  * Copyright (C) 2001 by James.Bottomley@HansenPartnership.com
 **-----------------------------------------------------------------------------
 **  
 **
 **-----------------------------------------------------------------------------
  */
 
 /* Notes:
  *
  * This driver is designed exclusively for these chips (virtually the
  * earliest of the scripts engine chips).  They need their own drivers
  * because they are missing so many of the scripts and snazzy register
  * features of their elder brothers (the 710, 720 and 770).
  *
  * The 700 is the lowliest of the line, it can only do async SCSI.
  * The 700-66 can at least do synchronous SCSI up to 10MHz.
  * 
  * The 700 chip has no host bus interface logic of its own.  However,
  * it is usually mapped to a location with well defined register
  * offsets.  Therefore, if you can determine the base address and the
  * irq your board incorporating this chip uses, you can probably use
  * this driver to run it (although you'll probably have to write a
  * minimal wrapper for the purpose---see the NCR_D700 driver for
  * details about how to do this).
  *
  *
  * TODO List:
  *
  * 1. Better statistics in the proc fs
  *
  * 2. Implement message queue (queues SCSI messages like commands) and make
  *    the abort and device reset functions use them.
  * */
 
 /* CHANGELOG
  *
  * Version 2.8
  *
  * Fixed bad bug affecting tag starvation processing (previously the
  * driver would hang the system if too many tags starved.  Also fixed
  * bad bug having to do with 10 byte command processing and REQUEST
  * SENSE (the command would loop forever getting a transfer length
  * mismatch in the CMD phase).
  *
  * Version 2.7
  *
  * Fixed scripts problem which caused certain devices (notably CDRWs)
  * to hang on initial INQUIRY.  Updated NCR_700_readl/writel to use
  * __raw_readl/writel for parisc compatibility (Thomas
  * Bogendoerfer). Added missing SCp->request_bufflen initialisation
  * for sense requests (Ryan Bradetich).
  *
  * Version 2.6
  *
  * Following test of the 64 bit parisc kernel by Richard Hirst,
  * several problems have now been corrected.  Also adds support for
  * consistent memory allocation.
  *
  * Version 2.5
  * 
  * More Compatibility changes for 710 (now actually works).  Enhanced
  * support for odd clock speeds which constrain SDTR negotiations.
  * correct cacheline separation for scsi messages and status for
  * incoherent architectures.  Use of the pci mapping functions on
  * buffers to begin support for 64 bit drivers.
  *
  * Version 2.4
  *
  * Added support for the 53c710 chip (in 53c700 emulation mode only---no 
  * special 53c710 instructions or registers are used).
  *
  * Version 2.3
  *
  * More endianness/cache coherency changes.
  *
  * Better bad device handling (handles devices lying about tag
  * queueing support and devices which fail to provide sense data on
  * contingent allegiance conditions)
  *
  * Many thanks to Richard Hirst <rhirst@linuxcare.com> for patiently
  * debugging this driver on the parisc architecture and suggesting
  * many improvements and bug fixes.
  *
  * Thanks also go to Linuxcare Inc. for providing several PARISC
  * machines for me to debug the driver on.
  *
  * Version 2.2
  *
  * Made the driver mem or io mapped; added endian invariance; added
  * dma cache flushing operations for architectures which need it;
  * added support for more varied clocking speeds.
  *
  * Version 2.1
  *
  * Initial modularisation from the D700.  See NCR_D700.c for the rest of
  * the changelog.
  * */
 #define NCR_700_VERSION "2.8"
 
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/string.h>
 #include <linux/slab.h>
 #include <linux/ioport.h>
 #include <linux/delay.h>
 #include <linux/spinlock.h>
 #include <linux/completion.h>
 #include <linux/init.h>
 #include <linux/proc_fs.h>
 #include <linux/blkdev.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/device.h>
 #include <linux/pgtable.h>
 #include <asm/dma.h>
 #include <asm/io.h>
 #include <asm/byteorder.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
 #include <scsi/scsi_dbg.h>
 #include <scsi/scsi_eh.h>
 #include <scsi/scsi_host.h>
 #include <scsi/scsi_tcq.h>
 #include <scsi/scsi_transport.h>
 #include <scsi/scsi_transport_spi.h>
 
 #include "53c700.h"
 
 /* NOTE: For 64 bit drivers there are points in the code where we use
  * a non dereferenceable pointer to point to a structure in dma-able
  * memory (which is 32 bits) so that we can use all of the structure
  * operations but take the address at the end.  This macro allows us
  * to truncate the 64 bit pointer down to 32 bits without the compiler
  * complaining */
 #define to32bit(x)  ((__u32)((unsigned long)(x)))
 
 #ifdef NCR_700_DEBUG
 #define STATIC
 #else
 #define STATIC static
 #endif
 
 MODULE_AUTHOR("James Bottomley");
 MODULE_DESCRIPTION("53c700 and 53c700-66 Driver");
 MODULE_LICENSE("GPL");
 
 /* This is the script */
 #include "53c700_d.h"
 
 
 STATIC int NCR_700_queuecommand(struct Scsi_Host *h, struct scsi_cmnd *);
 STATIC int NCR_700_abort(struct scsi_cmnd * SCpnt);
 STATIC int NCR_700_host_reset(struct scsi_cmnd * SCpnt);
 STATIC void NCR_700_chip_setup(struct Scsi_Host *host);
 STATIC void NCR_700_chip_reset(struct Scsi_Host *host);
 STATIC int NCR_700_slave_alloc(struct scsi_device *SDpnt);
 STATIC int NCR_700_slave_configure(struct scsi_device *SDpnt);
 STATIC void NCR_700_slave_destroy(struct scsi_device *SDpnt);
 static int NCR_700_change_queue_depth(struct scsi_device *SDpnt, int depth);
 
 STATIC const struct attribute_group *NCR_700_dev_groups[];
 
 STATIC struct scsi_transport_template *NCR_700_transport_template = NULL;
 
 static char *NCR_700_phase[] = {
     "",
     "after selection",
     "before command phase",
     "after command phase",
     "after status phase",
     "after data in phase",
     "after data out phase",
     "during data phase",
 };
 
 static char *NCR_700_condition[] = {
     "",
     "NOT MSG_OUT",
     "UNEXPECTED PHASE",
     "NOT MSG_IN",
     "UNEXPECTED MSG",
     "MSG_IN",
     "SDTR_MSG RECEIVED",
     "REJECT_MSG RECEIVED",
     "DISCONNECT_MSG RECEIVED",
     "MSG_OUT",
     "DATA_IN",
     
 };
 
 static char *NCR_700_fatal_messages[] = {
     "unexpected message after reselection",
     "still MSG_OUT after message injection",
     "not MSG_IN after selection",
     "Illegal message length received",
 };
 
 static char *NCR_700_SBCL_bits[] = {
     "IO ",
     "CD ",
     "MSG ",
     "ATN ",
     "SEL ",
     "BSY ",
     "ACK ",
     "REQ ",
 };
 
 static char *NCR_700_SBCL_to_phase[] = {
     "DATA_OUT",
     "DATA_IN",
     "CMD_OUT",
     "STATE",
     "ILLEGAL PHASE",
     "ILLEGAL PHASE",
     "MSG OUT",
     "MSG IN",
 };
 
 /* This translates the SDTR message offset and period to a value
  * which can be loaded into the SXFER_REG.
  *
  * NOTE: According to SCSI-2, the true transfer period (in ns) is
  *       actually four times this period value */
 static inline __u8
 NCR_700_offset_period_to_sxfer(struct NCR_700_Host_Parameters *hostdata,
                    __u8 offset, __u8 period)
 {
     int XFERP;
 
     __u8 min_xferp = (hostdata->chip710
               ? NCR_710_MIN_XFERP : NCR_700_MIN_XFERP);
     __u8 max_offset = (hostdata->chip710
                ? NCR_710_MAX_OFFSET : NCR_700_MAX_OFFSET);
 
     if(offset == 0)
         return 0;
 
     if(period < hostdata->min_period) {
         printk(KERN_WARNING "53c700: Period %dns is less than this chip's minimum, setting to %d\n", period*4, NCR_700_MIN_PERIOD*4);
         period = hostdata->min_period;
     }
     XFERP = (period*4 * hostdata->sync_clock)/1000 - 4;
     if(offset > max_offset) {
         printk(KERN_WARNING "53c700: Offset %d exceeds chip maximum, setting to %d\n",
                offset, max_offset);
         offset = max_offset;
     }
     if(XFERP < min_xferp) {
         XFERP =  min_xferp;
     }
     return (offset & 0x0f) | (XFERP & 0x07)<<4;
 }
 
 static inline __u8
 NCR_700_get_SXFER(struct scsi_device *SDp)
 {
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)SDp->host->hostdata[0];
 
     return NCR_700_offset_period_to_sxfer(hostdata,
                           spi_offset(SDp->sdev_target),
                           spi_period(SDp->sdev_target));
 }
 
 static inline dma_addr_t virt_to_dma(struct NCR_700_Host_Parameters *h, void *p)
 {
     return h->pScript + ((uintptr_t)p - (uintptr_t)h->script);
 }
 
 static inline void dma_sync_to_dev(struct NCR_700_Host_Parameters *h,
         void *addr, size_t size)
 {
     if (h->noncoherent)
         dma_sync_single_for_device(h->dev, virt_to_dma(h, addr),
                        size, DMA_BIDIRECTIONAL);
 }
 
 static inline void dma_sync_from_dev(struct NCR_700_Host_Parameters *h,
         void *addr, size_t size)
 {
     if (h->noncoherent)
         dma_sync_single_for_device(h->dev, virt_to_dma(h, addr), size,
                        DMA_BIDIRECTIONAL);
 }
 
 struct Scsi_Host *
 NCR_700_detect(struct scsi_host_template *tpnt,
            struct NCR_700_Host_Parameters *hostdata, struct device *dev)
 {
     dma_addr_t pScript, pSlots;
     __u8 *memory;
     __u32 *script;
     struct Scsi_Host *host;
     static int banner = 0;
     int j;
 
     if (tpnt->sdev_groups == NULL)
         tpnt->sdev_groups = NCR_700_dev_groups;
 
     memory = dma_alloc_coherent(dev, TOTAL_MEM_SIZE, &pScript, GFP_KERNEL);
     if (!memory) {
         hostdata->noncoherent = 1;
         memory = dma_alloc_noncoherent(dev, TOTAL_MEM_SIZE, &pScript,
                      DMA_BIDIRECTIONAL, GFP_KERNEL);
     }
     if (!memory) {
         printk(KERN_ERR "53c700: Failed to allocate memory for driver, detaching\n");
         return NULL;
     }
 
     script = (__u32 *)memory;
     hostdata->msgin = memory + MSGIN_OFFSET;
     hostdata->msgout = memory + MSGOUT_OFFSET;
     hostdata->status = memory + STATUS_OFFSET;
     hostdata->slots = (struct NCR_700_command_slot *)(memory + SLOTS_OFFSET);
     hostdata->dev = dev;
 
     pSlots = pScript + SLOTS_OFFSET;
 
     /* Fill in the missing routines from the host template */
     tpnt->queuecommand = NCR_700_queuecommand;
     tpnt->eh_abort_handler = NCR_700_abort;
     tpnt->eh_host_reset_handler = NCR_700_host_reset;
     tpnt->can_queue = NCR_700_COMMAND_SLOTS_PER_HOST;
     tpnt->sg_tablesize = NCR_700_SG_SEGMENTS;
     tpnt->cmd_per_lun = NCR_700_CMD_PER_LUN;
     tpnt->slave_configure = NCR_700_slave_configure;
     tpnt->slave_destroy = NCR_700_slave_destroy;
     tpnt->slave_alloc = NCR_700_slave_alloc;
     tpnt->change_queue_depth = NCR_700_change_queue_depth;
 
     if(tpnt->name == NULL)
         tpnt->name = "53c700";
     if(tpnt->proc_name == NULL)
         tpnt->proc_name = "53c700";
 
     host = scsi_host_alloc(tpnt, 4);
     if (!host)
         return NULL;
     memset(hostdata->slots, 0, sizeof(struct NCR_700_command_slot)
            * NCR_700_COMMAND_SLOTS_PER_HOST);
     for (j = 0; j < NCR_700_COMMAND_SLOTS_PER_HOST; j++) {
         dma_addr_t offset = (dma_addr_t)((unsigned long)&hostdata->slots[j].SG[0]
                       - (unsigned long)&hostdata->slots[0].SG[0]);
         hostdata->slots[j].pSG = (struct NCR_700_SG_List *)((unsigned long)(pSlots + offset));
         if(j == 0)
             hostdata->free_list = &hostdata->slots[j];
         else
             hostdata->slots[j-1].ITL_forw = &hostdata->slots[j];
         hostdata->slots[j].state = NCR_700_SLOT_FREE;
     }
 
     for (j = 0; j < ARRAY_SIZE(SCRIPT); j++)
         script[j] = bS_to_host(SCRIPT[j]);
 
     /* adjust all labels to be bus physical */
     for (j = 0; j < PATCHES; j++)
         script[LABELPATCHES[j]] = bS_to_host(pScript + SCRIPT[LABELPATCHES[j]]);
     /* now patch up fixed addresses. */
     script_patch_32(hostdata, script, MessageLocation,
             pScript + MSGOUT_OFFSET);
     script_patch_32(hostdata, script, StatusAddress,
             pScript + STATUS_OFFSET);
     script_patch_32(hostdata, script, ReceiveMsgAddress,
             pScript + MSGIN_OFFSET);
 
     hostdata->script = script;
     hostdata->pScript = pScript;
     dma_sync_single_for_device(hostdata->dev, pScript, sizeof(SCRIPT), DMA_TO_DEVICE);
     hostdata->state = NCR_700_HOST_FREE;
     hostdata->cmd = NULL;
     host->max_id = 8;
     host->max_lun = NCR_700_MAX_LUNS;
     BUG_ON(NCR_700_transport_template == NULL);
     host->transportt = NCR_700_transport_template;
     host->unique_id = (unsigned long)hostdata->base;
     hostdata->eh_complete = NULL;
     host->hostdata[0] = (unsigned long)hostdata;
     /* kick the chip */
     NCR_700_writeb(0xff, host, CTEST9_REG);
     if (hostdata->chip710)
         hostdata->rev = (NCR_700_readb(host, CTEST8_REG)>>4) & 0x0f;
     else
         hostdata->rev = (NCR_700_readb(host, CTEST7_REG)>>4) & 0x0f;
     hostdata->fast = (NCR_700_readb(host, CTEST9_REG) == 0);
     if (banner == 0) {
         printk(KERN_NOTICE "53c700: Version " NCR_700_VERSION " By James.Bottomley@HansenPartnership.com\n");
         banner = 1;
     }
     printk(KERN_NOTICE "scsi%d: %s rev %d %s\n", host->host_no,
            hostdata->chip710 ? "53c710" :
            (hostdata->fast ? "53c700-66" : "53c700"),
            hostdata->rev, hostdata->differential ?
            "(Differential)" : "");
     /* reset the chip */
     NCR_700_chip_reset(host);
 
     if (scsi_add_host(host, dev)) {
         dev_printk(KERN_ERR, dev, "53c700: scsi_add_host failed\n");
         scsi_host_put(host);
         return NULL;
     }
 
     spi_signalling(host) = hostdata->differential ? SPI_SIGNAL_HVD :
         SPI_SIGNAL_SE;
 
     return host;
 }
 
 int
 NCR_700_release(struct Scsi_Host *host)
 {
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)host->hostdata[0];
 
     if (hostdata->noncoherent)
         dma_free_noncoherent(hostdata->dev, TOTAL_MEM_SIZE,
                 hostdata->script, hostdata->pScript,
                 DMA_BIDIRECTIONAL);
     else
         dma_free_coherent(hostdata->dev, TOTAL_MEM_SIZE,
                   hostdata->script, hostdata->pScript);
     return 1;
 }
 
 static inline __u8
 NCR_700_identify(int can_disconnect, __u8 lun)
 {
     return IDENTIFY_BASE |
         ((can_disconnect) ? 0x40 : 0) |
         (lun & NCR_700_LUN_MASK);
 }
 
 /*
  * Function : static int data_residual (Scsi_Host *host)
  *
  * Purpose : return residual data count of what's in the chip.  If you
  * really want to know what this function is doing, it's almost a
  * direct transcription of the algorithm described in the 53c710
  * guide, except that the DBC and DFIFO registers are only 6 bits
  * wide on a 53c700.
  *
  * Inputs : host - SCSI host */
 static inline int
 NCR_700_data_residual (struct Scsi_Host *host) {
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)host->hostdata[0];
     int count, synchronous = 0;
     unsigned int ddir;
 
     if(hostdata->chip710) {
         count = ((NCR_700_readb(host, DFIFO_REG) & 0x7f) -
              (NCR_700_readl(host, DBC_REG) & 0x7f)) & 0x7f;
     } else {
         count = ((NCR_700_readb(host, DFIFO_REG) & 0x3f) -
              (NCR_700_readl(host, DBC_REG) & 0x3f)) & 0x3f;
     }
     
     if(hostdata->fast)
         synchronous = NCR_700_readb(host, SXFER_REG) & 0x0f;
     
     /* get the data direction */
     ddir = NCR_700_readb(host, CTEST0_REG) & 0x01;
 
     if (ddir) {
         /* Receive */
         if (synchronous) 
             count += (NCR_700_readb(host, SSTAT2_REG) & 0xf0) >> 4;
         else
             if (NCR_700_readb(host, SSTAT1_REG) & SIDL_REG_FULL)
                 ++count;
     } else {
         /* Send */
         __u8 sstat = NCR_700_readb(host, SSTAT1_REG);
         if (sstat & SODL_REG_FULL)
             ++count;
         if (synchronous && (sstat & SODR_REG_FULL))
             ++count;
     }
 #ifdef NCR_700_DEBUG
     if(count)
         printk("RESIDUAL IS %d (ddir %d)\n", count, ddir);
 #endif
     return count;
 }
 
 /* print out the SCSI wires and corresponding phase from the SBCL register
  * in the chip */
 static inline char *
 sbcl_to_string(__u8 sbcl)
 {
     int i;
     static char ret[256];
 
     ret[0]='\0';
     for(i=0; i<8; i++) {
         if((1<<i) & sbcl) 
             strcat(ret, NCR_700_SBCL_bits[i]);
     }
     strcat(ret, NCR_700_SBCL_to_phase[sbcl & 0x07]);
     return ret;
 }
 
 static inline __u8
 bitmap_to_number(__u8 bitmap)
 {
     __u8 i;
 
     for(i=0; i<8 && !(bitmap &(1<<i)); i++)
         ;
     return i;
 }
 
 /* Pull a slot off the free list */
 STATIC struct NCR_700_command_slot *
 find_empty_slot(struct NCR_700_Host_Parameters *hostdata)
 {
     struct NCR_700_command_slot *slot = hostdata->free_list;
 
     if(slot == NULL) {
         /* sanity check */
         if(hostdata->command_slot_count != NCR_700_COMMAND_SLOTS_PER_HOST)
             printk(KERN_ERR "SLOTS FULL, but count is %d, should be %d\n", hostdata->command_slot_count, NCR_700_COMMAND_SLOTS_PER_HOST);
         return NULL;
     }
 
     if(slot->state != NCR_700_SLOT_FREE)
         /* should panic! */
         printk(KERN_ERR "BUSY SLOT ON FREE LIST!!!\n");
         
 
     hostdata->free_list = slot->ITL_forw;
     slot->ITL_forw = NULL;
 
 
     /* NOTE: set the state to busy here, not queued, since this
      * indicates the slot is in use and cannot be run by the IRQ
      * finish routine.  If we cannot queue the command when it
      * is properly build, we then change to NCR_700_SLOT_QUEUED */
     slot->state = NCR_700_SLOT_BUSY;
     slot->flags = 0;
     hostdata->command_slot_count++;
     
     return slot;
 }
 
 STATIC void 
 free_slot(struct NCR_700_command_slot *slot,
       struct NCR_700_Host_Parameters *hostdata)
 {
     if((slot->state & NCR_700_SLOT_MASK) != NCR_700_SLOT_MAGIC) {
         printk(KERN_ERR "53c700: SLOT %p is not MAGIC!!!\n", slot);
     }
     if(slot->state == NCR_700_SLOT_FREE) {
         printk(KERN_ERR "53c700: SLOT %p is FREE!!!\n", slot);
     }
     
     slot->resume_offset = 0;
     slot->cmnd = NULL;
     slot->state = NCR_700_SLOT_FREE;
     slot->ITL_forw = hostdata->free_list;
     hostdata->free_list = slot;
     hostdata->command_slot_count--;
 }
 
 
 /* This routine really does very little.  The command is indexed on
    the ITL and (if tagged) the ITLQ lists in _queuecommand */
 STATIC void
 save_for_reselection(struct NCR_700_Host_Parameters *hostdata,
              struct scsi_cmnd *SCp, __u32 dsp)
 {
     /* Its just possible that this gets executed twice */
     if(SCp != NULL) {
         struct NCR_700_command_slot *slot =
             (struct NCR_700_command_slot *)SCp->host_scribble;
 
         slot->resume_offset = dsp;
     }
     hostdata->state = NCR_700_HOST_FREE;
     hostdata->cmd = NULL;
 }
 
 STATIC inline void
 NCR_700_unmap(struct NCR_700_Host_Parameters *hostdata, struct scsi_cmnd *SCp,
           struct NCR_700_command_slot *slot)
 {
     if(SCp->sc_data_direction != DMA_NONE &&
        SCp->sc_data_direction != DMA_BIDIRECTIONAL)
         scsi_dma_unmap(SCp);
 }
 
 STATIC inline void
 NCR_700_scsi_done(struct NCR_700_Host_Parameters *hostdata,
            struct scsi_cmnd *SCp, int result)
 {
     hostdata->state = NCR_700_HOST_FREE;
     hostdata->cmd = NULL;
 
     if(SCp != NULL) {
         struct NCR_700_command_slot *slot =
             (struct NCR_700_command_slot *)SCp->host_scribble;
 
         dma_unmap_single(hostdata->dev, slot->pCmd,
                  MAX_COMMAND_SIZE, DMA_TO_DEVICE);
         if (slot->flags == NCR_700_FLAG_AUTOSENSE) {
             char *cmnd = NCR_700_get_sense_cmnd(SCp->device);
 
             dma_unmap_single(hostdata->dev, slot->dma_handle,
                      SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
             /* restore the old result if the request sense was
              * successful */
             if (result == 0)
                 result = cmnd[7];
             /* restore the original length */
             SCp->cmd_len = cmnd[8];
         } else
             NCR_700_unmap(hostdata, SCp, slot);
 
         free_slot(slot, hostdata);
 #ifdef NCR_700_DEBUG
         if(NCR_700_get_depth(SCp->device) == 0 ||
            NCR_700_get_depth(SCp->device) > SCp->device->queue_depth)
             printk(KERN_ERR "Invalid depth in NCR_700_scsi_done(): %d\n",
                    NCR_700_get_depth(SCp->device));
 #endif /* NCR_700_DEBUG */
         NCR_700_set_depth(SCp->device, NCR_700_get_depth(SCp->device) - 1);
 
         SCp->host_scribble = NULL;
         SCp->result = result;
         scsi_done(SCp);
     } else {
         printk(KERN_ERR "53c700: SCSI DONE HAS NULL SCp\n");
     }
 }
 
 
 STATIC void
 NCR_700_internal_bus_reset(struct Scsi_Host *host)
 {
     /* Bus reset */
     NCR_700_writeb(ASSERT_RST, host, SCNTL1_REG);
     udelay(50);
     NCR_700_writeb(0, host, SCNTL1_REG);
 
 }
 
 STATIC void
 NCR_700_chip_setup(struct Scsi_Host *host)
 {
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)host->hostdata[0];
     __u8 min_period;
     __u8 min_xferp = (hostdata->chip710 ? NCR_710_MIN_XFERP : NCR_700_MIN_XFERP);
 
     if(hostdata->chip710) {
         __u8 burst_disable = 0;
         __u8 burst_length = 0;
 
         switch (hostdata->burst_length) {
             case 1:
                     burst_length = BURST_LENGTH_1;
                     break;
             case 2:
                     burst_length = BURST_LENGTH_2;
                     break;
             case 4:
                     burst_length = BURST_LENGTH_4;
                     break;
             case 8:
                     burst_length = BURST_LENGTH_8;
                     break;
             default:
                     burst_disable = BURST_DISABLE;
                     break;
         }
         hostdata->dcntl_extra |= COMPAT_700_MODE;
 
         NCR_700_writeb(hostdata->dcntl_extra, host, DCNTL_REG);
         NCR_700_writeb(burst_length | hostdata->dmode_extra,
                    host, DMODE_710_REG);
         NCR_700_writeb(burst_disable | hostdata->ctest7_extra |
                    (hostdata->differential ? DIFF : 0),
                    host, CTEST7_REG);
         NCR_700_writeb(BTB_TIMER_DISABLE, host, CTEST0_REG);
         NCR_700_writeb(FULL_ARBITRATION | ENABLE_PARITY | PARITY
                    | AUTO_ATN, host, SCNTL0_REG);
     } else {
         NCR_700_writeb(BURST_LENGTH_8 | hostdata->dmode_extra,
                    host, DMODE_700_REG);
         NCR_700_writeb(hostdata->differential ? 
                    DIFF : 0, host, CTEST7_REG);
         if(hostdata->fast) {
             /* this is for 700-66, does nothing on 700 */
             NCR_700_writeb(LAST_DIS_ENBL | ENABLE_ACTIVE_NEGATION 
                        | GENERATE_RECEIVE_PARITY, host,
                        CTEST8_REG);
         } else {
             NCR_700_writeb(FULL_ARBITRATION | ENABLE_PARITY
                        | PARITY | AUTO_ATN, host, SCNTL0_REG);
         }
     }
 
     NCR_700_writeb(1 << host->this_id, host, SCID_REG);
     NCR_700_writeb(0, host, SBCL_REG);
     NCR_700_writeb(ASYNC_OPERATION, host, SXFER_REG);
 
     NCR_700_writeb(PHASE_MM_INT | SEL_TIMEOUT_INT | GROSS_ERR_INT | UX_DISC_INT
          | RST_INT | PAR_ERR_INT | SELECT_INT, host, SIEN_REG);
 
     NCR_700_writeb(ABORT_INT | INT_INST_INT | ILGL_INST_INT, host, DIEN_REG);
     NCR_700_writeb(ENABLE_SELECT, host, SCNTL1_REG);
     if(hostdata->clock > 75) {
         printk(KERN_ERR "53c700: Clock speed %dMHz is too high: 75Mhz is the maximum this chip can be driven at\n", hostdata->clock);
         /* do the best we can, but the async clock will be out
          * of spec: sync divider 2, async divider 3 */
         DEBUG(("53c700: sync 2 async 3\n"));
         NCR_700_writeb(SYNC_DIV_2_0, host, SBCL_REG);
         NCR_700_writeb(ASYNC_DIV_3_0 | hostdata->dcntl_extra, host, DCNTL_REG);
         hostdata->sync_clock = hostdata->clock/2;
     } else  if(hostdata->clock > 50  && hostdata->clock <= 75) {
         /* sync divider 1.5, async divider 3 */
         DEBUG(("53c700: sync 1.5 async 3\n"));
         NCR_700_writeb(SYNC_DIV_1_5, host, SBCL_REG);
         NCR_700_writeb(ASYNC_DIV_3_0 | hostdata->dcntl_extra, host, DCNTL_REG);
         hostdata->sync_clock = hostdata->clock*2;
         hostdata->sync_clock /= 3;
         
     } else if(hostdata->clock > 37 && hostdata->clock <= 50) {
         /* sync divider 1, async divider 2 */
         DEBUG(("53c700: sync 1 async 2\n"));
         NCR_700_writeb(SYNC_DIV_1_0, host, SBCL_REG);
         NCR_700_writeb(ASYNC_DIV_2_0 | hostdata->dcntl_extra, host, DCNTL_REG);
         hostdata->sync_clock = hostdata->clock;
     } else if(hostdata->clock > 25 && hostdata->clock <=37) {
         /* sync divider 1, async divider 1.5 */
         DEBUG(("53c700: sync 1 async 1.5\n"));
         NCR_700_writeb(SYNC_DIV_1_0, host, SBCL_REG);
         NCR_700_writeb(ASYNC_DIV_1_5 | hostdata->dcntl_extra, host, DCNTL_REG);
         hostdata->sync_clock = hostdata->clock;
     } else {
         DEBUG(("53c700: sync 1 async 1\n"));
         NCR_700_writeb(SYNC_DIV_1_0, host, SBCL_REG);
         NCR_700_writeb(ASYNC_DIV_1_0 | hostdata->dcntl_extra, host, DCNTL_REG);
         /* sync divider 1, async divider 1 */
         hostdata->sync_clock = hostdata->clock;
     }
     /* Calculate the actual minimum period that can be supported
      * by our synchronous clock speed.  See the 710 manual for
      * exact details of this calculation which is based on a
      * setting of the SXFER register */
     min_period = 1000*(4+min_xferp)/(4*hostdata->sync_clock);
     hostdata->min_period = NCR_700_MIN_PERIOD;
     if(min_period > NCR_700_MIN_PERIOD)
         hostdata->min_period = min_period;
 }
 
 STATIC void
 NCR_700_chip_reset(struct Scsi_Host *host)
 {
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)host->hostdata[0];
     if(hostdata->chip710) {
         NCR_700_writeb(SOFTWARE_RESET_710, host, ISTAT_REG);
         udelay(100);
 
         NCR_700_writeb(0, host, ISTAT_REG);
     } else {
         NCR_700_writeb(SOFTWARE_RESET, host, DCNTL_REG);
         udelay(100);
         
         NCR_700_writeb(0, host, DCNTL_REG);
     }
 
     mdelay(1000);
 
     NCR_700_chip_setup(host);
 }
 
 /* The heart of the message processing engine is that the instruction
  * immediately after the INT is the normal case (and so must be CLEAR
  * ACK).  If we want to do something else, we call that routine in
  * scripts and set temp to be the normal case + 8 (skipping the CLEAR
  * ACK) so that the routine returns correctly to resume its activity
  * */
 STATIC __u32
 process_extended_message(struct Scsi_Host *host, 
              struct NCR_700_Host_Parameters *hostdata,
              struct scsi_cmnd *SCp, __u32 dsp, __u32 dsps)
 {
     __u32 resume_offset = dsp, temp = dsp + 8;
     __u8 pun = 0xff, lun = 0xff;
 
     if(SCp != NULL) {
         pun = SCp->device->id;
         lun = SCp->device->lun;
     }
 
     switch(hostdata->msgin[2]) {
     case A_SDTR_MSG:
         if(SCp != NULL && NCR_700_is_flag_set(SCp->device, NCR_700_DEV_BEGIN_SYNC_NEGOTIATION)) {
             struct scsi_target *starget = SCp->device->sdev_target;
             __u8 period = hostdata->msgin[3];
             __u8 offset = hostdata->msgin[4];
 
             if(offset == 0 || period == 0) {
                 offset = 0;
                 period = 0;
             }
 
             spi_offset(starget) = offset;
             spi_period(starget) = period;
             
             if(NCR_700_is_flag_set(SCp->device, NCR_700_DEV_PRINT_SYNC_NEGOTIATION)) {
                 spi_display_xfer_agreement(starget);
                 NCR_700_clear_flag(SCp->device, NCR_700_DEV_PRINT_SYNC_NEGOTIATION);
             }
             
             NCR_700_set_flag(SCp->device, NCR_700_DEV_NEGOTIATED_SYNC);
             NCR_700_clear_flag(SCp->device, NCR_700_DEV_BEGIN_SYNC_NEGOTIATION);
             
             NCR_700_writeb(NCR_700_get_SXFER(SCp->device),
                        host, SXFER_REG);
 
         } else {
             /* SDTR message out of the blue, reject it */
             shost_printk(KERN_WARNING, host,
                 "Unexpected SDTR msg\n");
             hostdata->msgout[0] = A_REJECT_MSG;
             dma_sync_to_dev(hostdata, hostdata->msgout, 1);
             script_patch_16(hostdata, hostdata->script,
                             MessageCount, 1);
             /* SendMsgOut returns, so set up the return
              * address */
             resume_offset = hostdata->pScript + Ent_SendMessageWithATN;
         }
         break;
     
     case A_WDTR_MSG:
         printk(KERN_INFO "scsi%d: (%d:%d), Unsolicited WDTR after CMD, Rejecting\n",
                host->host_no, pun, lun);
         hostdata->msgout[0] = A_REJECT_MSG;
         dma_sync_to_dev(hostdata, hostdata->msgout, 1);
         script_patch_16(hostdata, hostdata->script, MessageCount, 1);
         resume_offset = hostdata->pScript + Ent_SendMessageWithATN;
 
         break;
 
     default:
         printk(KERN_INFO "scsi%d (%d:%d): Unexpected message %s: ",
                host->host_no, pun, lun,
                NCR_700_phase[(dsps & 0xf00) >> 8]);
         spi_print_msg(hostdata->msgin);
         printk("\n");
         /* just reject it */
         hostdata->msgout[0] = A_REJECT_MSG;
         dma_sync_to_dev(hostdata, hostdata->msgout, 1);
         script_patch_16(hostdata, hostdata->script, MessageCount, 1);
         /* SendMsgOut returns, so set up the return
          * address */
         resume_offset = hostdata->pScript + Ent_SendMessageWithATN;
     }
     NCR_700_writel(temp, host, TEMP_REG);
     return resume_offset;
 }
 
 STATIC __u32
 process_message(struct Scsi_Host *host, struct NCR_700_Host_Parameters *hostdata,
         struct scsi_cmnd *SCp, __u32 dsp, __u32 dsps)
 {
     /* work out where to return to */
     __u32 temp = dsp + 8, resume_offset = dsp;
     __u8 pun = 0xff, lun = 0xff;
 
     if(SCp != NULL) {
         pun = SCp->device->id;
         lun = SCp->device->lun;
     }
 
 #ifdef NCR_700_DEBUG
     printk("scsi%d (%d:%d): message %s: ", host->host_no, pun, lun,
            NCR_700_phase[(dsps & 0xf00) >> 8]);
     spi_print_msg(hostdata->msgin);
     printk("\n");
 #endif
 
     switch(hostdata->msgin[0]) {
 
     case A_EXTENDED_MSG:
         resume_offset =  process_extended_message(host, hostdata, SCp,
                               dsp, dsps);
         break;
 
     case A_REJECT_MSG:
         if(SCp != NULL && NCR_700_is_flag_set(SCp->device, NCR_700_DEV_BEGIN_SYNC_NEGOTIATION)) {
             /* Rejected our sync negotiation attempt */
             spi_period(SCp->device->sdev_target) =
                 spi_offset(SCp->device->sdev_target) = 0;
             NCR_700_set_flag(SCp->device, NCR_700_DEV_NEGOTIATED_SYNC);
             NCR_700_clear_flag(SCp->device, NCR_700_DEV_BEGIN_SYNC_NEGOTIATION);
         } else if(SCp != NULL && NCR_700_get_tag_neg_state(SCp->device) == NCR_700_DURING_TAG_NEGOTIATION) {
             /* rejected our first simple tag message */
             scmd_printk(KERN_WARNING, SCp,
                 "Rejected first tag queue attempt, turning off tag queueing\n");
             /* we're done negotiating */
             NCR_700_set_tag_neg_state(SCp->device, NCR_700_FINISHED_TAG_NEGOTIATION);
             hostdata->tag_negotiated &= ~(1<<scmd_id(SCp));
 
             SCp->device->tagged_supported = 0;
             SCp->device->simple_tags = 0;
             scsi_change_queue_depth(SCp->device, host->cmd_per_lun);
         } else {
             shost_printk(KERN_WARNING, host,
                 "(%d:%d) Unexpected REJECT Message %s\n",
                    pun, lun,
                    NCR_700_phase[(dsps & 0xf00) >> 8]);
             /* however, just ignore it */
         }
         break;
 
     case A_PARITY_ERROR_MSG:
         printk(KERN_ERR "scsi%d (%d:%d) Parity Error!\n", host->host_no,
                pun, lun);
         NCR_700_internal_bus_reset(host);
         break;
     case A_SIMPLE_TAG_MSG:
         printk(KERN_INFO "scsi%d (%d:%d) SIMPLE TAG %d %s\n", host->host_no,
                pun, lun, hostdata->msgin[1],
                NCR_700_phase[(dsps & 0xf00) >> 8]);
         /* just ignore it */
         break;
     default:
         printk(KERN_INFO "scsi%d (%d:%d): Unexpected message %s: ",
                host->host_no, pun, lun,
                NCR_700_phase[(dsps & 0xf00) >> 8]);
 
         spi_print_msg(hostdata->msgin);
         printk("\n");
         /* just reject it */
         hostdata->msgout[0] = A_REJECT_MSG;
         dma_sync_to_dev(hostdata, hostdata->msgout, 1);
         script_patch_16(hostdata, hostdata->script, MessageCount, 1);
         /* SendMsgOut returns, so set up the return
          * address */
         resume_offset = hostdata->pScript + Ent_SendMessageWithATN;
 
         break;
     }
     NCR_700_writel(temp, host, TEMP_REG);
     /* set us up to receive another message */
     dma_sync_from_dev(hostdata, hostdata->msgin, MSG_ARRAY_SIZE);
     return resume_offset;
 }
 
 STATIC __u32
 process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,
              struct Scsi_Host *host,
              struct NCR_700_Host_Parameters *hostdata)
 {
     __u32 resume_offset = 0;
     __u8 pun = 0xff, lun=0xff;
 
     if(SCp != NULL) {
         pun = SCp->device->id;
         lun = SCp->device->lun;
     }
 
     if(dsps == A_GOOD_STATUS_AFTER_STATUS) {
         DEBUG(("  COMMAND COMPLETE, status=%02x\n",
                hostdata->status[0]));
         /* OK, if TCQ still under negotiation, we now know it works */
         if (NCR_700_get_tag_neg_state(SCp->device) == NCR_700_DURING_TAG_NEGOTIATION)
             NCR_700_set_tag_neg_state(SCp->device,
                           NCR_700_FINISHED_TAG_NEGOTIATION);
 
         /* check for contingent allegiance conditions */
         if (hostdata->status[0] == SAM_STAT_CHECK_CONDITION ||
             hostdata->status[0] == SAM_STAT_COMMAND_TERMINATED) {
             struct NCR_700_command_slot *slot =
                 (struct NCR_700_command_slot *)SCp->host_scribble;
             if(slot->flags == NCR_700_FLAG_AUTOSENSE) {
                 /* OOPS: bad device, returning another
                  * contingent allegiance condition */
                 scmd_printk(KERN_ERR, SCp,
                     "broken device is looping in contingent allegiance: ignoring\n");
                 NCR_700_scsi_done(hostdata, SCp, hostdata->status[0]);
             } else {
                 char *cmnd =
                     NCR_700_get_sense_cmnd(SCp->device);
 #ifdef NCR_DEBUG
                 scsi_print_command(SCp);
                 printk("  cmd %p has status %d, requesting sense\n",
                        SCp, hostdata->status[0]);
 #endif
                 /* we can destroy the command here
                  * because the contingent allegiance
                  * condition will cause a retry which
                  * will re-copy the command from the
                  * saved data_cmnd.  We also unmap any
                  * data associated with the command
                  * here */
                 NCR_700_unmap(hostdata, SCp, slot);
                 dma_unmap_single(hostdata->dev, slot->pCmd,
                          MAX_COMMAND_SIZE,
                          DMA_TO_DEVICE);
 
                 cmnd[0] = REQUEST_SENSE;
                 cmnd[1] = (lun & 0x7) << 5;
                 cmnd[2] = 0;
                 cmnd[3] = 0;
                 cmnd[4] = SCSI_SENSE_BUFFERSIZE;
                 cmnd[5] = 0;
                 /* Here's a quiet hack: the
                  * REQUEST_SENSE command is six bytes,
                  * so store a flag indicating that
                  * this was an internal sense request
                  * and the original status at the end
                  * of the command */
                 cmnd[6] = NCR_700_INTERNAL_SENSE_MAGIC;
                 cmnd[7] = hostdata->status[0];
                 cmnd[8] = SCp->cmd_len;
                 SCp->cmd_len = 6; /* command length for
                            * REQUEST_SENSE */
                 slot->pCmd = dma_map_single(hostdata->dev, cmnd, MAX_COMMAND_SIZE, DMA_TO_DEVICE);
                 slot->dma_handle = dma_map_single(hostdata->dev, SCp->sense_buffer, SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
                 slot->SG[0].ins = bS_to_host(SCRIPT_MOVE_DATA_IN | SCSI_SENSE_BUFFERSIZE);
                 slot->SG[0].pAddr = bS_to_host(slot->dma_handle);
                 slot->SG[1].ins = bS_to_host(SCRIPT_RETURN);
                 slot->SG[1].pAddr = 0;
                 slot->resume_offset = hostdata->pScript;
                 dma_sync_to_dev(hostdata, slot->SG, sizeof(slot->SG[0])*2);
                 dma_sync_from_dev(hostdata, SCp->sense_buffer, SCSI_SENSE_BUFFERSIZE);
 
                 /* queue the command for reissue */
                 slot->state = NCR_700_SLOT_QUEUED;
                 slot->flags = NCR_700_FLAG_AUTOSENSE;
                 hostdata->state = NCR_700_HOST_FREE;
                 hostdata->cmd = NULL;
             }
         } else {
             // Currently rely on the mid layer evaluation
             // of the tag queuing capability
             //
             //if(status_byte(hostdata->status[0]) == GOOD &&
             //   SCp->cmnd[0] == INQUIRY && SCp->use_sg == 0) {
             //  /* Piggy back the tag queueing support
             //   * on this command */
             //  dma_sync_single_for_cpu(hostdata->dev,
             //              slot->dma_handle,
             //              SCp->request_bufflen,
             //              DMA_FROM_DEVICE);
             //  if(((char *)SCp->request_buffer)[7] & 0x02) {
             //      scmd_printk(KERN_INFO, SCp,
             //           "Enabling Tag Command Queuing\n");
             //      hostdata->tag_negotiated |= (1<<scmd_id(SCp));
             //      NCR_700_set_flag(SCp->device, NCR_700_DEV_BEGIN_TAG_QUEUEING);
             //  } else {
             //      NCR_700_clear_flag(SCp->device, NCR_700_DEV_BEGIN_TAG_QUEUEING);
             //      hostdata->tag_negotiated &= ~(1<<scmd_id(SCp));
             //  }
             //}
             NCR_700_scsi_done(hostdata, SCp, hostdata->status[0]);
         }
     } else if((dsps & 0xfffff0f0) == A_UNEXPECTED_PHASE) {
         __u8 i = (dsps & 0xf00) >> 8;
 
         scmd_printk(KERN_ERR, SCp, "UNEXPECTED PHASE %s (%s)\n",
                NCR_700_phase[i],
                sbcl_to_string(NCR_700_readb(host, SBCL_REG)));
         scmd_printk(KERN_ERR, SCp, "         len = %d, cmd =",
             SCp->cmd_len);
         scsi_print_command(SCp);
 
         NCR_700_internal_bus_reset(host);
     } else if((dsps & 0xfffff000) == A_FATAL) {
         int i = (dsps & 0xfff);
 
         printk(KERN_ERR "scsi%d: (%d:%d) FATAL ERROR: %s\n",
                host->host_no, pun, lun, NCR_700_fatal_messages[i]);
         if(dsps == A_FATAL_ILLEGAL_MSG_LENGTH) {
             printk(KERN_ERR "     msg begins %02x %02x\n",
                    hostdata->msgin[0], hostdata->msgin[1]);
         }
         NCR_700_internal_bus_reset(host);
     } else if((dsps & 0xfffff0f0) == A_DISCONNECT) {
 #ifdef NCR_700_DEBUG
         __u8 i = (dsps & 0xf00) >> 8;
 
         printk("scsi%d: (%d:%d), DISCONNECTED (%d) %s\n",
                host->host_no, pun, lun,
                i, NCR_700_phase[i]);
 #endif
         save_for_reselection(hostdata, SCp, dsp);
 
     } else if(dsps == A_RESELECTION_IDENTIFIED) {
         __u8 lun;
         struct NCR_700_command_slot *slot;
         __u8 reselection_id = hostdata->reselection_id;
         struct scsi_device *SDp;
 
         lun = hostdata->msgin[0] & 0x1f;
 
         hostdata->reselection_id = 0xff;
         DEBUG(("scsi%d: (%d:%d) RESELECTED!\n",
                host->host_no, reselection_id, lun));
         /* clear the reselection indicator */
         SDp = __scsi_device_lookup(host, 0, reselection_id, lun);
         if(unlikely(SDp == NULL)) {
             printk(KERN_ERR "scsi%d: (%d:%d) HAS NO device\n",
                    host->host_no, reselection_id, lun);
             BUG();
         }
         if(hostdata->msgin[1] == A_SIMPLE_TAG_MSG) {
             struct scsi_cmnd *SCp;
 
             SCp = scsi_host_find_tag(SDp->host, hostdata->msgin[2]);
             if(unlikely(SCp == NULL)) {
                 printk(KERN_ERR "scsi%d: (%d:%d) no saved request for tag %d\n", 
                        host->host_no, reselection_id, lun, hostdata->msgin[2]);
                 BUG();
             }
 
             slot = (struct NCR_700_command_slot *)SCp->host_scribble;
             DDEBUG(KERN_DEBUG, SDp,
                 "reselection is tag %d, slot %p(%d)\n",
                 hostdata->msgin[2], slot, slot->tag);
         } else {
             struct NCR_700_Device_Parameters *p = SDp->hostdata;
             struct scsi_cmnd *SCp = p->current_cmnd;
 
             if(unlikely(SCp == NULL)) {
                 sdev_printk(KERN_ERR, SDp,
                     "no saved request for untagged cmd\n");
                 BUG();
             }
             slot = (struct NCR_700_command_slot *)SCp->host_scribble;
         }
 
         if(slot == NULL) {
             printk(KERN_ERR "scsi%d: (%d:%d) RESELECTED but no saved command (MSG = %02x %02x %02x)!!\n",
                    host->host_no, reselection_id, lun,
                    hostdata->msgin[0], hostdata->msgin[1],
                    hostdata->msgin[2]);
         } else {
             if(hostdata->state != NCR_700_HOST_BUSY)
                 printk(KERN_ERR "scsi%d: FATAL, host not busy during valid reselection!\n",
                        host->host_no);
             resume_offset = slot->resume_offset;
             hostdata->cmd = slot->cmnd;
 
             /* re-patch for this command */
             script_patch_32_abs(hostdata, hostdata->script,
                                 CommandAddress, slot->pCmd);
             script_patch_16(hostdata, hostdata->script,
                     CommandCount, slot->cmnd->cmd_len);
             script_patch_32_abs(hostdata, hostdata->script,
                                 SGScriptStartAddress,
                         to32bit(&slot->pSG[0].ins));
 
             /* Note: setting SXFER only works if we're
              * still in the MESSAGE phase, so it is vital
              * that ACK is still asserted when we process
              * the reselection message.  The resume offset
              * should therefore always clear ACK */
             NCR_700_writeb(NCR_700_get_SXFER(hostdata->cmd->device),
                        host, SXFER_REG);
             dma_sync_from_dev(hostdata, hostdata->msgin,
                        MSG_ARRAY_SIZE);
             dma_sync_to_dev(hostdata, hostdata->msgout,
                        MSG_ARRAY_SIZE);
             /* I'm just being paranoid here, the command should
              * already have been flushed from the cache */
             dma_sync_to_dev(hostdata, slot->cmnd->cmnd,
                        slot->cmnd->cmd_len);
 
 
             
         }
     } else if(dsps == A_RESELECTED_DURING_SELECTION) {
 
         /* This section is full of debugging code because I've
          * never managed to reach it.  I think what happens is
          * that, because the 700 runs with selection
          * interrupts enabled the whole time that we take a
          * selection interrupt before we manage to get to the
          * reselected script interrupt */
 
         __u8 reselection_id = NCR_700_readb(host, SFBR_REG);
         struct NCR_700_command_slot *slot;
         
         /* Take out our own ID */
         reselection_id &= ~(1<<host->this_id);
         
         /* I've never seen this happen, so keep this as a printk rather
          * than a debug */
         printk(KERN_INFO "scsi%d: (%d:%d) RESELECTION DURING SELECTION, dsp=%08x[%04x] state=%d, count=%d\n",
                host->host_no, reselection_id, lun, dsp, dsp - hostdata->pScript, hostdata->state, hostdata->command_slot_count);
 
         {
             /* FIXME: DEBUGGING CODE */
             __u32 SG = (__u32)bS_to_cpu(hostdata->script[A_SGScriptStartAddress_used[0]]);
             int i;
 
             for(i=0; i< NCR_700_COMMAND_SLOTS_PER_HOST; i++) {
                 if(SG >= to32bit(&hostdata->slots[i].pSG[0])
                    && SG <= to32bit(&hostdata->slots[i].pSG[NCR_700_SG_SEGMENTS]))
                     break;
             }
             printk(KERN_INFO "IDENTIFIED SG segment as being %08x in slot %p, cmd %p, slot->resume_offset=%08x\n", SG, &hostdata->slots[i], hostdata->slots[i].cmnd, hostdata->slots[i].resume_offset);
             SCp =  hostdata->slots[i].cmnd;
         }
 
         if(SCp != NULL) {
             slot = (struct NCR_700_command_slot *)SCp->host_scribble;
             /* change slot from busy to queued to redo command */
             slot->state = NCR_700_SLOT_QUEUED;
         }
         hostdata->cmd = NULL;
         
         if(reselection_id == 0) {
             if(hostdata->reselection_id == 0xff) {
                 printk(KERN_ERR "scsi%d: Invalid reselection during selection!!\n", host->host_no);
                 return 0;
             } else {
                 printk(KERN_ERR "scsi%d: script reselected and we took a selection interrupt\n",
                        host->host_no);
                 reselection_id = hostdata->reselection_id;
             }
         } else {
             
             /* convert to real ID */
             reselection_id = bitmap_to_number(reselection_id);
         }
         hostdata->reselection_id = reselection_id;
         /* just in case we have a stale simple tag message, clear it */
         hostdata->msgin[1] = 0;
         dma_sync_to_dev(hostdata, hostdata->msgin, MSG_ARRAY_SIZE);
         if(hostdata->tag_negotiated & (1<<reselection_id)) {
             resume_offset = hostdata->pScript + Ent_GetReselectionWithTag;
         } else {
             resume_offset = hostdata->pScript + Ent_GetReselectionData;
         }
     } else if(dsps == A_COMPLETED_SELECTION_AS_TARGET) {
         /* we've just disconnected from the bus, do nothing since
          * a return here will re-run the queued command slot
          * that may have been interrupted by the initial selection */
         DEBUG((" SELECTION COMPLETED\n"));
     } else if((dsps & 0xfffff0f0) == A_MSG_IN) { 
         resume_offset = process_message(host, hostdata, SCp,
                         dsp, dsps);
     } else if((dsps &  0xfffff000) == 0) {
         __u8 i = (dsps & 0xf0) >> 4, j = (dsps & 0xf00) >> 8;
         printk(KERN_ERR "scsi%d: (%d:%d), unhandled script condition %s %s at %04x\n",
                host->host_no, pun, lun, NCR_700_condition[i],
                NCR_700_phase[j], dsp - hostdata->pScript);
         if(SCp != NULL) {
             struct scatterlist *sg;
 
             scsi_print_command(SCp);
             scsi_for_each_sg(SCp, sg, scsi_sg_count(SCp) + 1, i) {
                 printk(KERN_INFO " SG[%d].length = %d, move_insn=%08x, addr %08x\n", i, sg->length, ((struct NCR_700_command_slot *)SCp->host_scribble)->SG[i].ins, ((struct NCR_700_command_slot *)SCp->host_scribble)->SG[i].pAddr);
             }
         }
         NCR_700_internal_bus_reset(host);
     } else if((dsps & 0xfffff000) == A_DEBUG_INTERRUPT) {
         printk(KERN_NOTICE "scsi%d (%d:%d) DEBUG INTERRUPT %d AT %08x[%04x], continuing\n",
                host->host_no, pun, lun, dsps & 0xfff, dsp, dsp - hostdata->pScript);
         resume_offset = dsp;
     } else {
         printk(KERN_ERR "scsi%d: (%d:%d), unidentified script interrupt 0x%x at %04x\n",
                host->host_no, pun, lun, dsps, dsp - hostdata->pScript);
         NCR_700_internal_bus_reset(host);
     }
     return resume_offset;
 }
 
 /* We run the 53c700 with selection interrupts always enabled.  This
  * means that the chip may be selected as soon as the bus frees.  On a
  * busy bus, this can be before the scripts engine finishes its
  * processing.  Therefore, part of the selection processing has to be
  * to find out what the scripts engine is doing and complete the
  * function if necessary (i.e. process the pending disconnect or save
  * the interrupted initial selection */
 STATIC inline __u32
 process_selection(struct Scsi_Host *host, __u32 dsp)
 {
     __u8 id = 0;    /* Squash compiler warning */
     int count = 0;
     __u32 resume_offset = 0;
     struct NCR_700_Host_Parameters *hostdata =
         (struct NCR_700_Host_Parameters *)host->hostdata[0];
     struct scsi_cmnd *SCp = hostdata->cmd;
     __u8 sbcl;
 
     for(count = 0; count < 5; count++) {
         id = NCR_700_readb(host, hostdata->chip710 ?
                    CTEST9_REG : SFBR_REG);
 
         /* Take out our own ID */
         id &= ~(1<<host->this_id);
         if(id != 0) 
             break;
         udelay(5);
     }
     sbcl = NCR_700_readb(host, SBCL_REG);
     if((sbcl & SBCL_IO) == 0) {
         /* mark as having been selected rather than reselected */
         id = 0xff;
     } else {
         /* convert to real ID */
         hostdata->reselection_id = id = bitmap_to_number(id);
         DEBUG(("scsi%d:  Reselected by %d\n",
                host->host_no, id));
     }
     if(hostdata->state == NCR_700_HOST_BUSY && SCp != NULL) {
         struct NCR_700_command_slot *slot =
             (struct NCR_700_command_slot *)SCp->host_scribble;
         DEBUG(("  ID %d WARNING: RESELECTION OF BUSY HOST, saving cmd %p, slot %p, addr %x [%04x], resume %x!\n", id, hostdata->cmd, slot, dsp, dsp - hostdata->pScript, resume_offset));
         
         switch(dsp - hostdata->pScript) {
         case Ent_Disconnect1:
         case Ent_Disconnect2:
             save_for_reselection(hostdata, SCp, Ent_Disconnect2 + hostdata->pScript);
             break;
         case Ent_Disconnect3:
         case Ent_Disconnect4:
             save_for_reselection(hostdata, SCp, Ent_Disconnect4 + hostdata->pScript);
             break;
         case Ent_Disconnect5:
         case Ent_Disconnect6:
             save_for_reselection(hostdata, SCp, Ent_Disconnect6 + hostdata->pScript);
             break;
         case Ent_Disconnect7:
         case Ent_Disconnect8:
             save_for_reselection(hostdata, SCp, Ent_Disconnect8 + hostdata->pScript);
             break;
         case Ent_Finish1:
         case Ent_Finish2:
             process_script_interrupt(A_GOOD_STATUS_AFTER_STATUS, dsp, SCp, host, hostdata);
             break;
             
         default:
             slot->state = NCR_700_SLOT_QUEUED;
             break;
             }
     }
     hostdata->state = NCR_700_HOST_BUSY;
     hostdata->cmd = NULL;
     /* clear any stale simple tag message */
     hostdata->msgin[1] = 0;
     dma_sync_to_dev(hostdata, hostdata->msgin, MSG_ARRAY_SIZE);
 
     if(id == 0xff) {
         /* Selected as target, Ignore */
         resume_offset = hostdata->pScript + Ent_SelectedAsTarget;
     } else if(hostdata->tag_negotiated & (1<<id)) {
         resume_offset = hostdata->pScript + Ent_GetReselectionWithTag;
     } else {
         resume_offset = hostdata->pScript + Ent_GetReselectionData;
     }
     return resume_offset;
 }
 
 static inline void
 NCR_700_clear_fifo(struct Scsi_Host *host) {
     const struct NCR_700_Host_Parameters *hostdata
         = (struct NCR_700_Host_Parameters *)host->hostdata[0];
     if(hostdata->chip710) {
         NCR_700_writeb(CLR_FIFO_710, host, CTEST8_REG);
     } else {
         NCR_700_writeb(CLR_FIFO, host, DFIFO_REG);
     }
 }
 
 static inline void
 NCR_700_flush_fifo(struct Scsi_Host *host) {
     const struct NCR_700_Host_Parameters *hostdata
         = (struct NCR_700_Host_Parameters *)host->hostdata[0];
     if(hostdata->chip710) {
         NCR_700_writeb(FLUSH_DMA_FIFO_710, host, CTEST8_REG);
         udelay(10);
         NCR_700_writeb(0, host, CTEST8_REG);
     } else {
         NCR_700_writeb(FLUSH_DMA_FIFO, host, DFIFO_REG);
         udelay(10);
         NCR_700_writeb(0, host, DFIFO_REG);
     }
 }
 
 
 /* The queue lock with interrupts disabled must be held on entry to
  * this function */
 STATIC int
 NCR_700_start_command(struct scsi_cmnd *SCp)
 {
     struct NCR_700_command_slot *slot =
         (struct NCR_700_command_slot *)SCp->host_scribble;
     struct NCR_700_Host_Parameters *hostdata =
         (struct NCR_700_Host_Parameters *)SCp->device->host->hostdata[0];
     __u16 count = 1;    /* for IDENTIFY message */
     u8 lun = SCp->device->lun;
 
     if(hostdata->state != NCR_700_HOST_FREE) {
         /* keep this inside the lock to close the race window where
          * the running command finishes on another CPU while we don't
          * change the state to queued on this one */
         slot->state = NCR_700_SLOT_QUEUED;
 
         DEBUG(("scsi%d: host busy, queueing command %p, slot %p\n",
                SCp->device->host->host_no, slot->cmnd, slot));
         return 0;
     }
     hostdata->state = NCR_700_HOST_BUSY;
     hostdata->cmd = SCp;
     slot->state = NCR_700_SLOT_BUSY;
     /* keep interrupts disabled until we have the command correctly
      * set up so we cannot take a selection interrupt */
 
     hostdata->msgout[0] = NCR_700_identify((SCp->cmnd[0] != REQUEST_SENSE &&
                         slot->flags != NCR_700_FLAG_AUTOSENSE),
                            lun);
     /* for INQUIRY or REQUEST_SENSE commands, we cannot be sure
      * if the negotiated transfer parameters still hold, so
      * always renegotiate them */
     if(SCp->cmnd[0] == INQUIRY || SCp->cmnd[0] == REQUEST_SENSE ||
        slot->flags == NCR_700_FLAG_AUTOSENSE) {
         NCR_700_clear_flag(SCp->device, NCR_700_DEV_NEGOTIATED_SYNC);
     }
 
     /* REQUEST_SENSE is asking for contingent I_T_L(_Q) status.
      * If a contingent allegiance condition exists, the device
      * will refuse all tags, so send the request sense as untagged
      * */
     if((hostdata->tag_negotiated & (1<<scmd_id(SCp)))
        && (slot->tag != SCSI_NO_TAG && SCp->cmnd[0] != REQUEST_SENSE &&
            slot->flags != NCR_700_FLAG_AUTOSENSE)) {
         count += spi_populate_tag_msg(&hostdata->msgout[count], SCp);
     }
 
     if(hostdata->fast &&
        NCR_700_is_flag_clear(SCp->device, NCR_700_DEV_NEGOTIATED_SYNC)) {
         count += spi_populate_sync_msg(&hostdata->msgout[count],
                 spi_period(SCp->device->sdev_target),
                 spi_offset(SCp->device->sdev_target));
         NCR_700_set_flag(SCp->device, NCR_700_DEV_BEGIN_SYNC_NEGOTIATION);
     }
 
     script_patch_16(hostdata, hostdata->script, MessageCount, count);
 
     script_patch_ID(hostdata, hostdata->script, Device_ID, 1<<scmd_id(SCp));
 
     script_patch_32_abs(hostdata, hostdata->script, CommandAddress,
                 slot->pCmd);
     script_patch_16(hostdata, hostdata->script, CommandCount, SCp->cmd_len);
     /* finally plumb the beginning of the SG list into the script
      * */
     script_patch_32_abs(hostdata, hostdata->script,
                         SGScriptStartAddress, to32bit(&slot->pSG[0].ins));
     NCR_700_clear_fifo(SCp->device->host);
 
     if(slot->resume_offset == 0)
         slot->resume_offset = hostdata->pScript;
     /* now perform all the writebacks and invalidates */
     dma_sync_to_dev(hostdata, hostdata->msgout, count);
     dma_sync_from_dev(hostdata, hostdata->msgin, MSG_ARRAY_SIZE);
     dma_sync_to_dev(hostdata, SCp->cmnd, SCp->cmd_len);
     dma_sync_from_dev(hostdata, hostdata->status, 1);
 
     /* set the synchronous period/offset */
     NCR_700_writeb(NCR_700_get_SXFER(SCp->device),
                SCp->device->host, SXFER_REG);
     NCR_700_writel(slot->temp, SCp->device->host, TEMP_REG);
     NCR_700_writel(slot->resume_offset, SCp->device->host, DSP_REG);
 
     return 1;
 }
 
 irqreturn_t
 NCR_700_intr(int irq, void *dev_id)
 {
     struct Scsi_Host *host = (struct Scsi_Host *)dev_id;
     struct NCR_700_Host_Parameters *hostdata =
         (struct NCR_700_Host_Parameters *)host->hostdata[0];
     __u8 istat;
     __u32 resume_offset = 0;
     __u8 pun = 0xff, lun = 0xff;
     unsigned long flags;
     int handled = 0;
 
     /* Use the host lock to serialise access to the 53c700
      * hardware.  Note: In future, we may need to take the queue
      * lock to enter the done routines.  When that happens, we
      * need to ensure that for this driver, the host lock and the
      * queue lock point to the same thing. */
     spin_lock_irqsave(host->host_lock, flags);
     if((istat = NCR_700_readb(host, ISTAT_REG))
           & (SCSI_INT_PENDING | DMA_INT_PENDING)) {
         __u32 dsps;
         __u8 sstat0 = 0, dstat = 0;
         __u32 dsp;
         struct scsi_cmnd *SCp = hostdata->cmd;
 
         handled = 1;
 
         if(istat & SCSI_INT_PENDING) {
             udelay(10);
 
             sstat0 = NCR_700_readb(host, SSTAT0_REG);
         }
 
         if(istat & DMA_INT_PENDING) {
             udelay(10);
 
             dstat = NCR_700_readb(host, DSTAT_REG);
         }
 
         dsps = NCR_700_readl(host, DSPS_REG);
         dsp = NCR_700_readl(host, DSP_REG);
 
         DEBUG(("scsi%d: istat %02x sstat0 %02x dstat %02x dsp %04x[%08x] dsps 0x%x\n",
                host->host_no, istat, sstat0, dstat,
                (dsp - (__u32)(hostdata->pScript))/4,
                dsp, dsps));
 
         if(SCp != NULL) {
             pun = SCp->device->id;
             lun = SCp->device->lun;
         }
 
         if(sstat0 & SCSI_RESET_DETECTED) {
             struct scsi_device *SDp;
             int i;
 
             hostdata->state = NCR_700_HOST_BUSY;
 
             printk(KERN_ERR "scsi%d: Bus Reset detected, executing command %p, slot %p, dsp %08x[%04x]\n",
                    host->host_no, SCp, SCp == NULL ? NULL : SCp->host_scribble, dsp, dsp - hostdata->pScript);
 
             scsi_report_bus_reset(host, 0);
 
             /* clear all the negotiated parameters */
             __shost_for_each_device(SDp, host)
                 NCR_700_clear_flag(SDp, ~0);
             
             /* clear all the slots and their pending commands */
             for(i = 0; i < NCR_700_COMMAND_SLOTS_PER_HOST; i++) {
                 struct scsi_cmnd *SCp;
                 struct NCR_700_command_slot *slot =
                     &hostdata->slots[i];
 
                 if(slot->state == NCR_700_SLOT_FREE)
                     continue;
                 
                 SCp = slot->cmnd;
                 printk(KERN_ERR " failing command because of reset, slot %p, cmnd %p\n",
                        slot, SCp);
                 free_slot(slot, hostdata);
                 SCp->host_scribble = NULL;
                 NCR_700_set_depth(SCp->device, 0);
                 /* NOTE: deadlock potential here: we
                  * rely on mid-layer guarantees that
                  * scsi_done won't try to issue the
                  * command again otherwise we'll
                  * deadlock on the
                  * hostdata->state_lock */
                 SCp->result = DID_RESET << 16;
                 scsi_done(SCp);
             }
             mdelay(25);
             NCR_700_chip_setup(host);
 
             hostdata->state = NCR_700_HOST_FREE;
             hostdata->cmd = NULL;
             /* signal back if this was an eh induced reset */
             if(hostdata->eh_complete != NULL)
                 complete(hostdata->eh_complete);
             goto out_unlock;
         } else if(sstat0 & SELECTION_TIMEOUT) {
             DEBUG(("scsi%d: (%d:%d) selection timeout\n",
                    host->host_no, pun, lun));
             NCR_700_scsi_done(hostdata, SCp, DID_NO_CONNECT<<16);
         } else if(sstat0 & PHASE_MISMATCH) {
             struct NCR_700_command_slot *slot = (SCp == NULL) ? NULL :
                 (struct NCR_700_command_slot *)SCp->host_scribble;
 
             if(dsp == Ent_SendMessage + 8 + hostdata->pScript) {
                 /* It wants to reply to some part of
                  * our message */
 #ifdef NCR_700_DEBUG
                 __u32 temp = NCR_700_readl(host, TEMP_REG);
                 int count = (hostdata->script[Ent_SendMessage/4] & 0xffffff) - ((NCR_700_readl(host, DBC_REG) & 0xffffff) + NCR_700_data_residual(host));
                 printk("scsi%d (%d:%d) PHASE MISMATCH IN SEND MESSAGE %d remain, return %p[%04x], phase %s\n", host->host_no, pun, lun, count, (void *)temp, temp - hostdata->pScript, sbcl_to_string(NCR_700_readb(host, SBCL_REG)));
 #endif
                 resume_offset = hostdata->pScript + Ent_SendMessagePhaseMismatch;
             } else if(dsp >= to32bit(&slot->pSG[0].ins) &&
                   dsp <= to32bit(&slot->pSG[NCR_700_SG_SEGMENTS].ins)) {
                 int data_transfer = NCR_700_readl(host, DBC_REG) & 0xffffff;
                 int SGcount = (dsp - to32bit(&slot->pSG[0].ins))/sizeof(struct NCR_700_SG_List);
                 int residual = NCR_700_data_residual(host);
                 int i;
 #ifdef NCR_700_DEBUG
                 __u32 naddr = NCR_700_readl(host, DNAD_REG);
 
                 printk("scsi%d: (%d:%d) Expected phase mismatch in slot->SG[%d], transferred 0x%x\n",
                        host->host_no, pun, lun,
                        SGcount, data_transfer);
                 scsi_print_command(SCp);
                 if(residual) {
                     printk("scsi%d: (%d:%d) Expected phase mismatch in slot->SG[%d], transferred 0x%x, residual %d\n",
                        host->host_no, pun, lun,
                        SGcount, data_transfer, residual);
                 }
 #endif
                 data_transfer += residual;
 
                 if(data_transfer != 0) {
                     int count; 
                     __u32 pAddr;
 
                     SGcount--;
 
                     count = (bS_to_cpu(slot->SG[SGcount].ins) & 0x00ffffff);
                     DEBUG(("DATA TRANSFER MISMATCH, count = %d, transferred %d\n", count, count-data_transfer));
                     slot->SG[SGcount].ins &= bS_to_host(0xff000000);
                     slot->SG[SGcount].ins |= bS_to_host(data_transfer);
                     pAddr = bS_to_cpu(slot->SG[SGcount].pAddr);
                     pAddr += (count - data_transfer);
 #ifdef NCR_700_DEBUG
                     if(pAddr != naddr) {
                         printk("scsi%d (%d:%d) transfer mismatch pAddr=%lx, naddr=%lx, data_transfer=%d, residual=%d\n", host->host_no, pun, lun, (unsigned long)pAddr, (unsigned long)naddr, data_transfer, residual);
                     }
 #endif
                     slot->SG[SGcount].pAddr = bS_to_host(pAddr);
                 }
                 /* set the executed moves to nops */
                 for(i=0; i<SGcount; i++) {
                     slot->SG[i].ins = bS_to_host(SCRIPT_NOP);
                     slot->SG[i].pAddr = 0;
                 }
                 dma_sync_to_dev(hostdata, slot->SG, sizeof(slot->SG));
                 /* and pretend we disconnected after
                  * the command phase */
                 resume_offset = hostdata->pScript + Ent_MsgInDuringData;
                 /* make sure all the data is flushed */
                 NCR_700_flush_fifo(host);
             } else {
                 __u8 sbcl = NCR_700_readb(host, SBCL_REG);
                 printk(KERN_ERR "scsi%d: (%d:%d) phase mismatch at %04x, phase %s\n",
                        host->host_no, pun, lun, dsp - hostdata->pScript, sbcl_to_string(sbcl));
                 NCR_700_internal_bus_reset(host);
             }
 
         } else if(sstat0 & SCSI_GROSS_ERROR) {
             printk(KERN_ERR "scsi%d: (%d:%d) GROSS ERROR\n",
                    host->host_no, pun, lun);
             NCR_700_scsi_done(hostdata, SCp, DID_ERROR<<16);
         } else if(sstat0 & PARITY_ERROR) {
             printk(KERN_ERR "scsi%d: (%d:%d) PARITY ERROR\n",
                    host->host_no, pun, lun);
             NCR_700_scsi_done(hostdata, SCp, DID_ERROR<<16);
         } else if(dstat & SCRIPT_INT_RECEIVED) {
             DEBUG(("scsi%d: (%d:%d) ====>SCRIPT INTERRUPT<====\n",
                    host->host_no, pun, lun));
             resume_offset = process_script_interrupt(dsps, dsp, SCp, host, hostdata);
         } else if(dstat & (ILGL_INST_DETECTED)) {
             printk(KERN_ERR "scsi%d: (%d:%d) Illegal Instruction detected at 0x%08x[0x%x]!!!\n"
                    "         Please email James.Bottomley@HansenPartnership.com with the details\n",
                    host->host_no, pun, lun,
                    dsp, dsp - hostdata->pScript);
             NCR_700_scsi_done(hostdata, SCp, DID_ERROR<<16);
         } else if(dstat & (WATCH_DOG_INTERRUPT|ABORTED)) {
             printk(KERN_ERR "scsi%d: (%d:%d) serious DMA problem, dstat=%02x\n",
                    host->host_no, pun, lun, dstat);
             NCR_700_scsi_done(hostdata, SCp, DID_ERROR<<16);
         }
 
         
         /* NOTE: selection interrupt processing MUST occur
          * after script interrupt processing to correctly cope
          * with the case where we process a disconnect and
          * then get reselected before we process the
          * disconnection */
         if(sstat0 & SELECTED) {
             /* FIXME: It currently takes at least FOUR
              * interrupts to complete a command that
              * disconnects: one for the disconnect, one
              * for the reselection, one to get the
              * reselection data and one to complete the
              * command.  If we guess the reselected
              * command here and prepare it, we only need
              * to get a reselection data interrupt if we
              * guessed wrongly.  Since the interrupt
              * overhead is much greater than the command
              * setup, this would be an efficient
              * optimisation particularly as we probably
              * only have one outstanding command on a
              * target most of the time */
 
             resume_offset = process_selection(host, dsp);
 
         }
 
     }
 
     if(resume_offset) {
         if(hostdata->state != NCR_700_HOST_BUSY) {
             printk(KERN_ERR "scsi%d: Driver error: resume at 0x%08x [0x%04x] with non busy host!\n",
                    host->host_no, resume_offset, resume_offset - hostdata->pScript);
             hostdata->state = NCR_700_HOST_BUSY;
         }
 
         DEBUG(("Attempting to resume at %x\n", resume_offset));
         NCR_700_clear_fifo(host);
         NCR_700_writel(resume_offset, host, DSP_REG);
     } 
     /* There is probably a technical no-no about this: If we're a
      * shared interrupt and we got this interrupt because the
      * other device needs servicing not us, we're still going to
      * check our queued commands here---of course, there shouldn't
      * be any outstanding.... */
     if(hostdata->state == NCR_700_HOST_FREE) {
         int i;
 
         for(i = 0; i < NCR_700_COMMAND_SLOTS_PER_HOST; i++) {
             /* fairness: always run the queue from the last
              * position we left off */
             int j = (i + hostdata->saved_slot_position)
                 % NCR_700_COMMAND_SLOTS_PER_HOST;
             
             if(hostdata->slots[j].state != NCR_700_SLOT_QUEUED)
                 continue;
             if(NCR_700_start_command(hostdata->slots[j].cmnd)) {
                 DEBUG(("scsi%d: Issuing saved command slot %p, cmd %p\t\n",
                        host->host_no, &hostdata->slots[j],
                        hostdata->slots[j].cmnd));
                 hostdata->saved_slot_position = j + 1;
             }
 
             break;
         }
     }
  out_unlock:
     spin_unlock_irqrestore(host->host_lock, flags);
     return IRQ_RETVAL(handled);
 }
 
 static int NCR_700_queuecommand_lck(struct scsi_cmnd *SCp)
 {
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)SCp->device->host->hostdata[0];
     __u32 move_ins;
     struct NCR_700_command_slot *slot;
 
     if(hostdata->command_slot_count >= NCR_700_COMMAND_SLOTS_PER_HOST) {
         /* We're over our allocation, this should never happen
          * since we report the max allocation to the mid layer */
         printk(KERN_WARNING "scsi%d: Command depth has gone over queue depth\n", SCp->device->host->host_no);
         return 1;
     }
     /* check for untagged commands.  We cannot have any outstanding
      * commands if we accept them.  Commands could be untagged because:
      *
      * - The tag negotiated bitmap is clear
      * - The blk layer sent and untagged command
      */
     if(NCR_700_get_depth(SCp->device) != 0
        && (!(hostdata->tag_negotiated & (1<<scmd_id(SCp)))
            || !(SCp->flags & SCMD_TAGGED))) {
         CDEBUG(KERN_ERR, SCp, "has non zero depth %d\n",
                NCR_700_get_depth(SCp->device));
         return SCSI_MLQUEUE_DEVICE_BUSY;
     }
     if(NCR_700_get_depth(SCp->device) >= SCp->device->queue_depth) {
         CDEBUG(KERN_ERR, SCp, "has max tag depth %d\n",
                NCR_700_get_depth(SCp->device));
         return SCSI_MLQUEUE_DEVICE_BUSY;
     }
     NCR_700_set_depth(SCp->device, NCR_700_get_depth(SCp->device) + 1);
 
     /* begin the command here */
     /* no need to check for NULL, test for command_slot_count above
      * ensures a slot is free */
     slot = find_empty_slot(hostdata);
 
     slot->cmnd = SCp;
 
     SCp->host_scribble = (unsigned char *)slot;
 
 #ifdef NCR_700_DEBUG
     printk("53c700: scsi%d, command ", SCp->device->host->host_no);
     scsi_print_command(SCp);
 #endif
     if ((SCp->flags & SCMD_TAGGED)
        && (hostdata->tag_negotiated &(1<<scmd_id(SCp))) == 0
        && NCR_700_get_tag_neg_state(SCp->device) == NCR_700_START_TAG_NEGOTIATION) {
         scmd_printk(KERN_ERR, SCp, "Enabling Tag Command Queuing\n");
         hostdata->tag_negotiated |= (1<<scmd_id(SCp));
         NCR_700_set_tag_neg_state(SCp->device, NCR_700_DURING_TAG_NEGOTIATION);
     }
 
     /* here we may have to process an untagged command.  The gate
      * above ensures that this will be the only one outstanding,
      * so clear the tag negotiated bit.
      *
      * FIXME: This will royally screw up on multiple LUN devices
      * */
     if (!(SCp->flags & SCMD_TAGGED)
        && (hostdata->tag_negotiated &(1<<scmd_id(SCp)))) {
         scmd_printk(KERN_INFO, SCp, "Disabling Tag Command Queuing\n");
         hostdata->tag_negotiated &= ~(1<<scmd_id(SCp));
     }
 
     if ((hostdata->tag_negotiated & (1<<scmd_id(SCp))) &&
         SCp->device->simple_tags) {
         slot->tag = scsi_cmd_to_rq(SCp)->tag;
         CDEBUG(KERN_DEBUG, SCp, "sending out tag %d, slot %p\n",
                slot->tag, slot);
     } else {
         struct NCR_700_Device_Parameters *p = SCp->device->hostdata;
 
         slot->tag = SCSI_NO_TAG;
         /* save current command for reselection */
         p->current_cmnd = SCp;
     }
     /* sanity check: some of the commands generated by the mid-layer
      * have an eccentric idea of their sc_data_direction */
     if(!scsi_sg_count(SCp) && !scsi_bufflen(SCp) &&
        SCp->sc_data_direction != DMA_NONE) {
 #ifdef NCR_700_DEBUG
         printk("53c700: Command");
         scsi_print_command(SCp);
         printk("Has wrong data direction %d\n", SCp->sc_data_direction);
 #endif
         SCp->sc_data_direction = DMA_NONE;
     }
 
     switch (SCp->cmnd[0]) {
     case REQUEST_SENSE:
         /* clear the internal sense magic */
         SCp->cmnd[6] = 0;
         fallthrough;
     default:
         /* OK, get it from the command */
         switch(SCp->sc_data_direction) {
         case DMA_BIDIRECTIONAL:
         default:
             printk(KERN_ERR "53c700: Unknown command for data direction ");
             scsi_print_command(SCp);
             
             move_ins = 0;
             break;
         case DMA_NONE:
             move_ins = 0;
             break;
         case DMA_FROM_DEVICE:
             move_ins = SCRIPT_MOVE_DATA_IN;
             break;
         case DMA_TO_DEVICE:
             move_ins = SCRIPT_MOVE_DATA_OUT;
             break;
         }
     }
 
     /* now build the scatter gather list */
     if(move_ins != 0) {
         int i;
         int sg_count;
         dma_addr_t vPtr = 0;
         struct scatterlist *sg;
         __u32 count = 0;
 
         sg_count = scsi_dma_map(SCp);
         BUG_ON(sg_count < 0);
 
         scsi_for_each_sg(SCp, sg, sg_count, i) {
             vPtr = sg_dma_address(sg);
             count = sg_dma_len(sg);
 
             slot->SG[i].ins = bS_to_host(move_ins | count);
             DEBUG((" scatter block %d: move %d[%08x] from 0x%lx\n",
                    i, count, slot->SG[i].ins, (unsigned long)vPtr));
             slot->SG[i].pAddr = bS_to_host(vPtr);
         }
         slot->SG[i].ins = bS_to_host(SCRIPT_RETURN);
         slot->SG[i].pAddr = 0;
         dma_sync_to_dev(hostdata, slot->SG, sizeof(slot->SG));
         DEBUG((" SETTING %p to %x\n",
                (&slot->pSG[i].ins),
                slot->SG[i].ins));
     }
     slot->resume_offset = 0;
     slot->pCmd = dma_map_single(hostdata->dev, SCp->cmnd,
                     MAX_COMMAND_SIZE, DMA_TO_DEVICE);
     NCR_700_start_command(SCp);
     return 0;
 }
 
 STATIC DEF_SCSI_QCMD(NCR_700_queuecommand)
 
 STATIC int
 NCR_700_abort(struct scsi_cmnd * SCp)
 {
     struct NCR_700_command_slot *slot;
 
     scmd_printk(KERN_INFO, SCp, "abort command\n");
 
     slot = (struct NCR_700_command_slot *)SCp->host_scribble;
 
     if(slot == NULL)
         /* no outstanding command to abort */
         return SUCCESS;
     if(SCp->cmnd[0] == TEST_UNIT_READY) {
         /* FIXME: This is because of a problem in the new
          * error handler.  When it is in error recovery, it
          * will send a TUR to a device it thinks may still be
          * showing a problem.  If the TUR isn't responded to,
          * it will abort it and mark the device off line.
          * Unfortunately, it does no other error recovery, so
          * this would leave us with an outstanding command
          * occupying a slot.  Rather than allow this to
          * happen, we issue a bus reset to force all
          * outstanding commands to terminate here. */
         NCR_700_internal_bus_reset(SCp->device->host);
         /* still drop through and return failed */
     }
     return FAILED;
 
 }
 
 STATIC int
 NCR_700_host_reset(struct scsi_cmnd * SCp)
 {
     DECLARE_COMPLETION_ONSTACK(complete);
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)SCp->device->host->hostdata[0];
 
     scmd_printk(KERN_INFO, SCp,
         "New error handler wants HOST reset, cmd %p\n\t", SCp);
     scsi_print_command(SCp);
 
     /* In theory, eh_complete should always be null because the
      * eh is single threaded, but just in case we're handling a
      * reset via sg or something */
     spin_lock_irq(SCp->device->host->host_lock);
     while (hostdata->eh_complete != NULL) {
         spin_unlock_irq(SCp->device->host->host_lock);
         msleep_interruptible(100);
         spin_lock_irq(SCp->device->host->host_lock);
     }
 
     hostdata->eh_complete = &complete;
     NCR_700_internal_bus_reset(SCp->device->host);
     NCR_700_chip_reset(SCp->device->host);
 
     spin_unlock_irq(SCp->device->host->host_lock);
     wait_for_completion(&complete);
     spin_lock_irq(SCp->device->host->host_lock);
 
     hostdata->eh_complete = NULL;
     /* Revalidate the transport parameters of the failing device */
     if(hostdata->fast)
         spi_schedule_dv_device(SCp->device);
 
     spin_unlock_irq(SCp->device->host->host_lock);
     return SUCCESS;
 }
 
 STATIC void
 NCR_700_set_period(struct scsi_target *STp, int period)
 {
     struct Scsi_Host *SHp = dev_to_shost(STp->dev.parent);
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)SHp->hostdata[0];
     
     if(!hostdata->fast)
         return;
 
     if(period < hostdata->min_period)
         period = hostdata->min_period;
 
     spi_period(STp) = period;
     spi_flags(STp) &= ~(NCR_700_DEV_NEGOTIATED_SYNC |
                 NCR_700_DEV_BEGIN_SYNC_NEGOTIATION);
     spi_flags(STp) |= NCR_700_DEV_PRINT_SYNC_NEGOTIATION;
 }
 
 STATIC void
 NCR_700_set_offset(struct scsi_target *STp, int offset)
 {
     struct Scsi_Host *SHp = dev_to_shost(STp->dev.parent);
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)SHp->hostdata[0];
     int max_offset = hostdata->chip710
         ? NCR_710_MAX_OFFSET : NCR_700_MAX_OFFSET;
     
     if(!hostdata->fast)
         return;
 
     if(offset > max_offset)
         offset = max_offset;
 
     /* if we're currently async, make sure the period is reasonable */
     if(spi_offset(STp) == 0 && (spi_period(STp) < hostdata->min_period ||
                     spi_period(STp) > 0xff))
         spi_period(STp) = hostdata->min_period;
 
     spi_offset(STp) = offset;
     spi_flags(STp) &= ~(NCR_700_DEV_NEGOTIATED_SYNC |
                 NCR_700_DEV_BEGIN_SYNC_NEGOTIATION);
     spi_flags(STp) |= NCR_700_DEV_PRINT_SYNC_NEGOTIATION;
 }
 
 STATIC int
 NCR_700_slave_alloc(struct scsi_device *SDp)
 {
     SDp->hostdata = kzalloc(sizeof(struct NCR_700_Device_Parameters),
                 GFP_KERNEL);
 
     if (!SDp->hostdata)
         return -ENOMEM;
 
     return 0;
 }
 
 STATIC int
 NCR_700_slave_configure(struct scsi_device *SDp)
 {
     struct NCR_700_Host_Parameters *hostdata = 
         (struct NCR_700_Host_Parameters *)SDp->host->hostdata[0];
 
     /* to do here: allocate memory; build a queue_full list */
     if(SDp->tagged_supported) {
         scsi_change_queue_depth(SDp, NCR_700_DEFAULT_TAGS);
         NCR_700_set_tag_neg_state(SDp, NCR_700_START_TAG_NEGOTIATION);
     }
 
     if(hostdata->fast) {
         /* Find the correct offset and period via domain validation */
         if (!spi_initial_dv(SDp->sdev_target))
             spi_dv_device(SDp);
     } else {
         spi_offset(SDp->sdev_target) = 0;
         spi_period(SDp->sdev_target) = 0;
     }
     return 0;
 }
 
 STATIC void
 NCR_700_slave_destroy(struct scsi_device *SDp)
 {
     kfree(SDp->hostdata);
     SDp->hostdata = NULL;
 }
 
 static int
 NCR_700_change_queue_depth(struct scsi_device *SDp, int depth)
 {
     if (depth > NCR_700_MAX_TAGS)
         depth = NCR_700_MAX_TAGS;
     return scsi_change_queue_depth(SDp, depth);
 }
 
 static ssize_t
 NCR_700_show_active_tags(struct device *dev, struct device_attribute *attr, char *buf)
 {
     struct scsi_device *SDp = to_scsi_device(dev);
 
     return snprintf(buf, 20, "%d\n", NCR_700_get_depth(SDp));
 }
 
 static struct device_attribute NCR_700_active_tags_attr = {
     .attr = {
         .name =     "active_tags",
         .mode =     S_IRUGO,
     },
     .show = NCR_700_show_active_tags,
 };
 
 STATIC struct attribute *NCR_700_dev_attrs[] = {
     &NCR_700_active_tags_attr.attr,
     NULL,
 };
 
 ATTRIBUTE_GROUPS(NCR_700_dev);
 
 EXPORT_SYMBOL(NCR_700_detect);
 EXPORT_SYMBOL(NCR_700_release);
 EXPORT_SYMBOL(NCR_700_intr);
 
 static struct spi_function_template NCR_700_transport_functions =  {
     .set_period = NCR_700_set_period,
     .show_period    = 1,
     .set_offset = NCR_700_set_offset,
     .show_offset    = 1,
 };
 
 static int __init NCR_700_init(void)
 {
     NCR_700_transport_template = spi_attach_transport(&NCR_700_transport_functions);
     if(!NCR_700_transport_template)
         return -ENODEV;
     return 0;
 }
 
 static void __exit NCR_700_exit(void)
 {
     spi_release_transport(NCR_700_transport_template);
 }
 
 module_init(NCR_700_init);
 module_exit(NCR_700_exit);
 

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