Import 2.3.18pre1
[davej-history.git] / drivers / scsi / esp.c
dissimilarity index 68%
index 2b1b8a5..1a6b860 100644 (file)
-/* esp.c:  EnhancedScsiProcessor Sun SCSI driver code.
- *
- * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
- */
-
-#include <linux/kernel.h>
-#include <linux/delay.h>
-#include <linux/types.h>
-#include <linux/string.h>
-#include <linux/malloc.h>
-#include <linux/blk.h>
-#include <linux/proc_fs.h>
-#include <linux/stat.h>
-
-#include "scsi.h"
-#include "hosts.h"
-#include "esp.h"
-
-#include <asm/sbus.h>
-#include <asm/dma.h>
-#include <asm/system.h>
-#include <asm/idprom.h>
-#include <asm/machines.h>
-#include <asm/ptrace.h>
-#include <asm/pgtable.h>
-#include <asm/oplib.h>
-#include <asm/vaddrs.h>
-#include <asm/io.h>
-
-#define DEBUG_ESP
-/* #define DEBUG_ESP_SG */
-
-#if defined(DEBUG_ESP)
-#define ESPLOG(foo)  printk foo
-#else
-#define ESPLOG(foo)
-#endif /* (DEBUG_ESP) */
-
-#define INTERNAL_ESP_ERROR \
-        (panic ("Internal ESP driver error in file %s, line %d\n", \
-               __FILE__, __LINE__))
-
-#define INTERNAL_ESP_ERROR_NOPANIC \
-        (printk ("Internal ESP driver error in file %s, line %d\n", \
-                __FILE__, __LINE__))
-
-/* This enum will be expanded when we have sync code written. */
-enum {
-       not_issued   = 0x01,  /* Still in the issue_SC queue.          */
-       in_selection = 0x02,  /* ESP is arbitrating, awaiting IRQ      */
-       in_datain    = 0x04,  /* Data is transferring over the bus     */
-       in_dataout   = 0x08,  /* Data is transferring over the bus     */
-       in_status    = 0x10,  /* Awaiting status/msg bytes from target */
-       in_finale    = 0x11,  /* Sent Msg ack, awaiting disconnect     */
-};
-
-struct proc_dir_entry proc_scsi_esp = {
-       PROC_SCSI_ESP, 3, "esp",
-       S_IFDIR | S_IRUGO | S_IXUGO, 2
-};
-
-struct Sparc_ESP *espchain;
-
-static void esp_intr(int irq, void *dev_id, struct pt_regs *pregs);
-static void esp_done(struct Sparc_ESP *esp, int error);
-
-/* Debugging routines */
-struct esp_cmdstrings {
-       unchar cmdchar;
-       char *text;
-} esp_cmd_strings[] = {
-       /* Miscellaneous */
-       { ESP_CMD_NULL, "ESP_NOP", },
-       { ESP_CMD_FLUSH, "FIFO_FLUSH", },
-       { ESP_CMD_RC, "RSTESP", },
-       { ESP_CMD_RS, "RSTSCSI", },
-       /* Disconnected State Group */
-       { ESP_CMD_RSEL, "RESLCTSEQ", },
-       { ESP_CMD_SEL, "SLCTNATN", },
-       { ESP_CMD_SELA, "SLCTATN", },
-       { ESP_CMD_SELAS, "SLCTATNSTOP", },
-       { ESP_CMD_ESEL, "ENSLCTRESEL", },
-       { ESP_CMD_DSEL, "DISSELRESEL", },
-       { ESP_CMD_SA3, "SLCTATN3", },
-       { ESP_CMD_RSEL3, "RESLCTSEQ", },
-       /* Target State Group */
-       { ESP_CMD_SMSG, "SNDMSG", },
-       { ESP_CMD_SSTAT, "SNDSTATUS", },
-       { ESP_CMD_SDATA, "SNDDATA", },
-       { ESP_CMD_DSEQ, "DISCSEQ", },
-       { ESP_CMD_TSEQ, "TERMSEQ", },
-       { ESP_CMD_TCCSEQ, "TRGTCMDCOMPSEQ", },
-       { ESP_CMD_DCNCT, "DISC", },
-       { ESP_CMD_RMSG, "RCVMSG", },
-       { ESP_CMD_RCMD, "RCVCMD", },
-       { ESP_CMD_RDATA, "RCVDATA", },
-       { ESP_CMD_RCSEQ, "RCVCMDSEQ", },
-       /* Initiator State Group */
-       { ESP_CMD_TI, "TRANSINFO", },
-       { ESP_CMD_ICCSEQ, "INICMDSEQCOMP", },
-       { ESP_CMD_MOK, "MSGACCEPTED", },
-       { ESP_CMD_TPAD, "TPAD", },
-       { ESP_CMD_SATN, "SATN", },
-       { ESP_CMD_RATN, "RATN", },
-};
-#define NUM_ESP_COMMANDS  ((sizeof(esp_cmd_strings)) / (sizeof(struct esp_cmdstrings)))
-
-/* Print textual representation of an ESP command */
-static inline void esp_print_cmd(unchar espcmd)
-{
-       unchar dma_bit = espcmd & ESP_CMD_DMA;
-       int i;
-
-       espcmd &= ~dma_bit;
-       for(i=0; i<NUM_ESP_COMMANDS; i++)
-               if(esp_cmd_strings[i].cmdchar == espcmd)
-                       break;
-       if(i==NUM_ESP_COMMANDS)
-               printk("ESP_Unknown");
-       else
-               printk("%s%s", esp_cmd_strings[i].text,
-                      ((dma_bit) ? "+DMA" : ""));
-}
-
-/* Print the status register's value */
-static inline void esp_print_statreg(unchar statreg)
-{
-       unchar phase;
-
-       printk("STATUS<");
-       phase = statreg & ESP_STAT_PMASK;
-       printk("%s,", (phase == ESP_DOP ? "DATA-OUT" :
-                      (phase == ESP_DIP ? "DATA-IN" :
-                       (phase == ESP_CMDP ? "COMMAND" :
-                        (phase == ESP_STATP ? "STATUS" :
-                         (phase == ESP_MOP ? "MSG-OUT" :
-                          (phase == ESP_MIP ? "MSG_IN" :
-                           "unknown")))))));
-       if(statreg & ESP_STAT_TDONE)
-               printk("TRANS_DONE,");
-       if(statreg & ESP_STAT_TCNT)
-               printk("TCOUNT_ZERO,");
-       if(statreg & ESP_STAT_PERR)
-               printk("P_ERROR,");
-       if(statreg & ESP_STAT_SPAM)
-               printk("SPAM,");
-       if(statreg & ESP_STAT_INTR)
-               printk("IRQ,");
-       printk(">");
-}
-
-/* Print the interrupt register's value */
-static inline void esp_print_ireg(unchar intreg)
-{
-       printk("INTREG< ");
-       if(intreg & ESP_INTR_S)
-               printk("SLCT_NATN ");
-       if(intreg & ESP_INTR_SATN)
-               printk("SLCT_ATN ");
-       if(intreg & ESP_INTR_RSEL)
-               printk("RSLCT ");
-       if(intreg & ESP_INTR_FDONE)
-               printk("FDONE ");
-       if(intreg & ESP_INTR_BSERV)
-               printk("BSERV ");
-       if(intreg & ESP_INTR_DC)
-               printk("DISCNCT ");
-       if(intreg & ESP_INTR_IC)
-               printk("ILL_CMD ");
-       if(intreg & ESP_INTR_SR)
-               printk("SCSI_BUS_RESET ");
-       printk(">");
-}
-
-/* Print the sequence step registers contents */
-static inline void esp_print_seqreg(unchar stepreg)
-{
-       stepreg &= ESP_STEP_VBITS;
-       printk("STEP<%s>",
-              (stepreg == ESP_STEP_ASEL ? "SLCT_ARB_CMPLT" :
-               (stepreg == ESP_STEP_SID ? "1BYTE_MSG_SENT" :
-                (stepreg == ESP_STEP_NCMD ? "NOT_IN_CMD_PHASE" :
-                 (stepreg == ESP_STEP_PPC ? "CMD_BYTES_LOST" :
-                  (stepreg == ESP_STEP_FINI ? "CMD_SENT_OK" :
-                   "UNKNOWN"))))));
-}
-
-/* Manipulation of the ESP command queues.  Thanks to the aha152x driver
- * and its author, Juergen E. Fischer, for the methods used here.
- * Note that these are per-ESP queues, not global queues like
- * the aha152x driver uses.
- */
-static inline void append_SC(Scsi_Cmnd **SC, Scsi_Cmnd *new_SC)
-{
-       Scsi_Cmnd *end;
-       unsigned long flags;
-
-       save_flags(flags); cli();
-       new_SC->host_scribble = (unsigned char *) NULL;
-       if(!*SC)
-               *SC = new_SC;
-       else {
-               for(end=*SC;end->host_scribble;end=(Scsi_Cmnd *)end->host_scribble)
-                       ;
-               end->host_scribble = (unsigned char *) new_SC;
-       }
-       restore_flags(flags);
-}
-
-static inline Scsi_Cmnd *remove_first_SC(Scsi_Cmnd **SC)
-{
-       Scsi_Cmnd *ptr;
-       unsigned long flags;
-
-       save_flags(flags); cli();
-       ptr = *SC;
-       if(ptr)
-               *SC = (Scsi_Cmnd *) (*SC)->host_scribble;
-       restore_flags(flags);
-       return ptr;
-}
-
-static inline Scsi_Cmnd *remove_SC(Scsi_Cmnd **SC, int target, int lun)
-{
-       Scsi_Cmnd *ptr, *prev;
-       unsigned long flags;
-
-       save_flags(flags); cli();
-       for(ptr = *SC, prev = NULL;
-           ptr && ((ptr->target != target) || (ptr->lun != lun));
-           prev = ptr, ptr = (Scsi_Cmnd *) ptr->host_scribble)
-               ;
-       if(ptr) {
-               if(prev)
-                       prev->host_scribble=ptr->host_scribble;
-               else
-                       *SC=(Scsi_Cmnd *)ptr->host_scribble;
-       }
-       restore_flags(flags);
-       return ptr;
-}
-
-static inline void do_pause(unsigned amount)
-{
-       unsigned long the_time = jiffies + amount;
-
-       while(jiffies < the_time)
-               barrier(); /* Not really needed, but... */
-}
-
-/* This places the ESP into a known state at boot time. */
-static inline void esp_bootup_reset(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
-{
-       struct sparc_dma_registers *dregs = esp->dregs;
-       volatile unchar trash;
-
-       /* Punt the DVMA into a known state. */
-       dregs->cond_reg |= DMA_RST_SCSI;
-       do_pause(100);
-       dregs->cond_reg &= ~(DMA_RST_SCSI);
-       if(esp->dma->revision == dvmarev2)
-               if(esp->erev != esp100)
-                       dregs->cond_reg |= DMA_3CLKS;
-       else if(esp->dma->revision == dvmarev3)
-               if(esp->erev == fas236 || esp->erev == fas100a) {
-                       dregs->cond_reg &= ~(DMA_3CLKS);
-                       dregs->cond_reg |= DMA_2CLKS;
-               }
-       else if(esp->dma->revision == dvmaesc1)
-               dregs->cond_reg |= DMA_ADD_ENABLE;
-       DMA_INTSON(dregs);
-
-       /* Now reset the ESP chip */
-       eregs->esp_cmd = ESP_CMD_RC;
-       eregs->esp_cmd = (ESP_CMD_NULL | ESP_CMD_DMA);
-       eregs->esp_cmd = (ESP_CMD_NULL | ESP_CMD_DMA); /* borken hardware... */
-
-       /* Reload the configuration registers */
-       eregs->esp_cfg1  = esp->config1;
-       eregs->esp_cfact = esp->cfact;
-       eregs->esp_stp   = 0;
-       eregs->esp_soff  = 0;
-       eregs->esp_timeo = esp->sync_defp;
-       if(esp->erev == esp100a || esp->erev == esp236)
-               eregs->esp_cfg2 = esp->config2;
-       if(esp->erev == esp236)
-               eregs->esp_cfg3 = esp->config3[0];
-       /* Eat any bitrot in the chip */
-       trash = eregs->esp_intrpt;
-
-       /* Reset the SCSI bus, but tell ESP not to generate an irq */
-       eregs->esp_cfg1 |= ESP_CONFIG1_SRRDISAB;
-       eregs->esp_cmd = ESP_CMD_RS;
-       do_pause(200);
-       eregs->esp_cfg1 = esp->config1;
-
-       /* Eat any bitrot in the chip and we are done... */
-       trash = eregs->esp_intrpt;
-}
-
-/* Detecting ESP chips on the machine.  This is the simple and easy
- * version.
- */
-int esp_detect(Scsi_Host_Template *tpnt)
-{
-       struct Sparc_ESP *esp, *elink;
-       struct Scsi_Host *esp_host;
-       struct linux_sbus *sbus;
-       struct linux_sbus_device *esp_dev, *sbdev_iter;
-       struct Sparc_ESP_regs *eregs;
-       struct sparc_dma_registers *dregs;
-       struct Linux_SBus_DMA *dma, *dlink;
-       unsigned int fmhz;
-       unchar ccf, bsizes, bsizes_more;
-       int nesps = 0;
-       int esp_node;
-
-       espchain = 0;
-       if(!SBus_chain)
-               panic("No SBUS in esp_detect()");
-       for_each_sbus(sbus) {
-               for_each_sbusdev(sbdev_iter, sbus) {
-                       /* Is it an esp sbus device? */
-                       esp_dev = sbdev_iter;
-                       if(strcmp(esp_dev->prom_name, "esp") &&
-                          strcmp(esp_dev->prom_name, "SUNW,esp")) {
-                               if(!esp_dev->child ||
-                                  strcmp(esp_dev->prom_name, "espdma"))
-                                       continue; /* nope... */
-                               esp_dev = esp_dev->child;
-                               if(strcmp(esp_dev->prom_name, "esp") &&
-                                  strcmp(esp_dev->prom_name, "SUNW,esp"))
-                                       continue; /* how can this happen? */
-                       }
-                       esp_host = scsi_register(tpnt, sizeof(struct Sparc_ESP));
-                       if(!esp_host)
-                               panic("Cannot register ESP SCSI host");
-                       esp = (struct Sparc_ESP *) esp_host->hostdata;
-                       if(!esp)
-                               panic("No esp in hostdata");
-                       esp->ehost = esp_host;
-                       esp->edev = esp_dev;
-                       /* Put into the chain of esp chips detected */
-                       if(espchain) {
-                               elink = espchain;
-                               while(elink->next) elink = elink->next;
-                               elink->next = esp;
-                       } else {
-                               espchain = esp;
-                       }
-                       esp->next = 0;
-
-                       /* Get misc. prom information */
-#define ESP_IS_MY_DVMA(esp, dma)  \
-       ((esp->edev->my_bus == dma->SBus_dev->my_bus) && \
-         (esp->edev->slot == dma->SBus_dev->slot) && \
-        (!strcmp(dma->SBus_dev->prom_name, "dma") || \
-         !strcmp(dma->SBus_dev->prom_name, "espdma")))
-
-                       esp_node = esp_dev->prom_node;
-                       prom_getstring(esp_node, "name", esp->prom_name,
-                                      sizeof(esp->prom_name));
-                       esp->prom_node = esp_node;
-                       for_each_dvma(dlink) {
-                               if(ESP_IS_MY_DVMA(esp, dlink) && !dlink->allocated)
-                                       break;
-                       }
-#undef ESP_IS_MY_DVMA
-                       /* If we don't know how to handle the dvma, do not use this device */
-                       if(!dlink){
-                               printk ("Cannot find dvma for ESP SCSI\n");
-                               scsi_unregister (esp_host);
-                               continue;
-                       }
-                       if (dlink->allocated){
-                               printk ("esp: can't use my espdma\n");
-                               scsi_unregister (esp_host);
-                               continue;
-                       }
-                       dlink->allocated = 1;
-                       dma = dlink;
-                       esp->dma = dma;
-                       esp->dregs = dregs = dma->regs;
-
-                       /* Map in the ESP registers from I/O space */
-                       prom_apply_sbus_ranges(esp->edev->reg_addrs, 1);
-                       esp->eregs = eregs = (struct Sparc_ESP_regs *)
-                               sparc_alloc_io(esp->edev->reg_addrs[0].phys_addr, 0,
-                                              PAGE_SIZE, "ESP Registers",
-                                              esp->edev->reg_addrs[0].which_io, 0x0);
-                       if(!eregs)
-                               panic("ESP registers unmappable");
-                       esp->esp_command =
-                               sparc_dvma_malloc(16, "ESP DVMA Cmd Block");
-                       if(!esp->esp_command)
-                               panic("ESP DVMA transport area unmappable");
-
-                       /* Set up the irq's etc. */
-                       esp->ehost->base = (unsigned char *) esp->eregs;
-                       esp->ehost->io_port = (unsigned int) esp->eregs;
-                       esp->ehost->n_io_port = (unsigned char)
-                               esp->edev->reg_addrs[0].reg_size;
-                       /* XXX The following may be different on sun4ms XXX */
-                       esp->ehost->irq = esp->irq = esp->edev->irqs[0].pri;
-
-                       /* Allocate the irq only if necessary */
-                       for_each_esp(elink) {
-                               if((elink != esp) && (esp->irq == elink->irq)) {
-                                       goto esp_irq_acquired; /* BASIC rulez */
-                               }
-                       }
-                       /* XXX We have shared interrupts per level now, maybe
-                        * XXX use them, maybe not...
-                        */
-                       if(request_irq(esp->ehost->irq, esp_intr, SA_INTERRUPT,
-                                      "Sparc ESP SCSI", NULL))
-                               panic("Cannot acquire ESP irq line");
-esp_irq_acquired:
-                       printk("esp%d: IRQ %d ", nesps, esp->ehost->irq);
-                       /* Figure out our scsi ID on the bus */
-                       esp->scsi_id = prom_getintdefault(esp->prom_node,
-                                                         "initiator-id", -1);
-                       if(esp->scsi_id == -1)
-                               esp->scsi_id = prom_getintdefault(esp->prom_node,
-                                                                 "scsi-initiator-id", -1);
-                       if(esp->scsi_id == -1)
-                               esp->scsi_id =
-                                       prom_getintdefault(esp->edev->my_bus->prom_node,
-                                                          "scsi-initiator-id", 7);
-                       esp->ehost->this_id = esp->scsi_id;
-                       esp->scsi_id_mask = (1 << esp->scsi_id);
-                       /* Check for differential bus */
-                       esp->diff = prom_getintdefault(esp->prom_node, "differential", -1);
-                       esp->diff = (esp->diff == -1) ? 0 : 1;
-                       /* Check out the clock properties of the chip */
-                       fmhz = prom_getintdefault(esp->prom_node, "clock-frequency", -1);
-                       if(fmhz==-1)
-                               fmhz = prom_getintdefault(esp->edev->my_bus->prom_node,
-                                                         "clock-frequency", -1);
-                       if(fmhz <= (5000))
-                               ccf = 0;
-                       else
-                               ccf = (((5000 - 1) + (fmhz))/(5000));
-                       if(!ccf || ccf > 8) {
-                               ccf = ESP_CCF_F4;
-                               fmhz = (5000 * 4);
-                       }
-                       if(ccf==(ESP_CCF_F7+1))
-                               esp->cfact = ESP_CCF_F0;
-                       else if(ccf == ESP_CCF_NEVER)
-                               esp->cfact = ESP_CCF_F2;
-                       else
-                               esp->cfact = ccf;
-                       esp->cfreq = fmhz;
-                       esp->ccycle = ((1000000000) / ((fmhz)/1000));
-                       esp->ctick = ((7682 * esp->cfact * esp->ccycle)/1000);
-                       esp->sync_defp = ((7682 + esp->ctick - 1) / esp->ctick);
-
-                       /* XXX HACK HACK HACK XXX */
-                       if (esp->sync_defp < 153)
-                               esp->sync_defp = 153;
-
-                       printk("SCSI ID %d  Clock %d MHz Period %2x ", esp->scsi_id,
-                              (fmhz / 1000), esp->sync_defp);
-
-                       /* Find the burst sizes this dma supports. */
-                       bsizes = prom_getintdefault(esp->prom_node, "burst-sizes", 0xff);
-                       bsizes_more = prom_getintdefault(esp->edev->my_bus->prom_node,
-                                                        "burst-sizes", 0xff);
-                       if(bsizes_more != 0xff) bsizes &= bsizes_more;
-                       if(bsizes == 0xff || (bsizes & DMA_BURST16)==0 ||
-                          (bsizes & DMA_BURST32)==0)
-                               bsizes = (DMA_BURST32 - 1);
-                       esp->bursts = bsizes;
-
-                       /* Probe the revision of this esp */
-                       esp->config1 = (ESP_CONFIG1_PENABLE | (esp->scsi_id & 7));
-                       esp->config2 = (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY);
-                       esp->config3[0] = ESP_CONFIG3_TENB;
-                       eregs->esp_cfg2 = esp->config2;
-                       if((eregs->esp_cfg2 & ~(ESP_CONFIG2_MAGIC)) !=
-                          (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY)) {
-                               printk("NCR53C90(esp100) detected\n");
-                               esp->erev = esp100;
-                       } else {
-                               eregs->esp_cfg2 = esp->config2 = 0;
-                               eregs->esp_cfg3 = 0;
-                               eregs->esp_cfg3 = esp->config3[0] = 5;
-                               if(eregs->esp_cfg3 != 5) {
-                                       printk("NCR53C90A(esp100a) detected\n");
-                                       esp->erev = esp100a;
-                               } else {
-                                       int target;
-
-                                       for(target=0; target<8; target++)
-                                               esp->config3[target] = 0;
-                                       eregs->esp_cfg3 = 0;
-                                       if(esp->cfact > ESP_CCF_F5) {
-                                               printk("NCR53C9XF(espfast) detected\n");
-                                               esp->erev = fast;
-                                               esp->config2 |= ESP_CONFIG2_FENAB;
-                                               eregs->esp_cfg2 = esp->config2;
-                                       } else {
-                                               printk("NCR53C9x(esp236) detected\n");
-                                               esp->erev = esp236;
-                                               eregs->esp_cfg2 = esp->config2 = 0;
-                                       }
-                               }
-                       }                               
-
-                       /* Initialize the command queues */
-                       esp->current_SC = 0;
-                       esp->disconnected_SC = 0;
-                       esp->issue_SC = 0;
-
-                       /* Reset the thing before we try anything... */
-                       esp_bootup_reset(esp, eregs);
-
-                       nesps++;
-#ifdef THREADED_ESP_DRIVER
-                       kernel_thread(esp_kernel_thread, esp, 0);
-#endif
-               } /* for each sbusdev */
-       } /* for each sbus */
-       return nesps;
-}
-
-/*
- * The info function will return whatever useful
- * information the developer sees fit.  If not provided, then
- * the name field will be used instead.
- */
-const char *esp_info(struct Scsi_Host *host)
-{
-       struct Sparc_ESP *esp;
-
-       esp = (struct Sparc_ESP *) host->hostdata;
-       switch(esp->erev) {
-       case esp100:
-               return "Sparc ESP100 (NCR53C90)";
-       case esp100a:
-               return "Sparc ESP100A (NCR53C90A)";
-       case esp236:
-               return "Sparc ESP236";
-       case fast:
-               return "Sparc ESP-FAST (236 or 100A)";
-       case fas236:
-               return "Sparc ESP236-FAST";
-       case fas100a:
-               return "Sparc ESP100A-FAST";
-       default:
-               panic("Bogon ESP revision");
-       };
-}
-
-/* Execute a SCSI command when the bus is free.   All callers
- * turn off all interrupts, so we don't need to explicitly do
- * it here.
- */
-static inline void esp_exec_cmd(struct Sparc_ESP *esp)
-{
-       struct sparc_dma_registers *dregs;
-       struct Sparc_ESP_regs *eregs;
-       Scsi_Cmnd *SCptr;
-       int i;
-
-       eregs = esp->eregs;
-       dregs = esp->dregs;
-
-       /* Grab first member of the issue queue. */
-       SCptr = esp->current_SC = remove_first_SC(&esp->issue_SC);
-       if(!SCptr)
-               goto bad;
-       SCptr->SCp.phase = in_selection;
-
-       /* NCR docs say:
-        * 1) Load select/reselect Bus ID register with target ID
-        * 2) Load select/reselect Timeout Reg with desired value
-        * 3) Load Synchronous offset register with zero (for
-        *    asynchronous transfers).
-        * 4) Load Synchronous Transfer Period register (if
-        *    synchronous)
-        * 5) Load FIFO with 6, 10, or 12 byte SCSI command
-        * 6) Issue SELECTION_WITHOUT_ATTENTION command
-        *
-        * They also mention that a DMA NOP command must be issued
-        * to the SCSI chip under many circumstances, plus it's
-        * also a good idea to flush out the fifo just in case.
-        */
-
-       /* Load zeros into COUNTER via 2 DMA NOP chip commands
-        * due to flaky implementations of the 53C9x which don't
-        * get the idea the first time around.
-        */
-       dregs->cond_reg = (DMA_INT_ENAB | DMA_FIFO_INV);
-
-       eregs->esp_tclow = 0;
-       eregs->esp_tcmed = 0;
-       eregs->esp_cmd   = (ESP_CMD_NULL | ESP_CMD_DMA);
-
-       /* Flush the fifo of excess garbage. */
-       eregs->esp_cmd   = ESP_CMD_FLUSH;
-
-       /* Load bus-id and timeout values. */
-       eregs->esp_busid = (SCptr->target & 7);
-       eregs->esp_timeo = esp->sync_defp;
-
-       eregs->esp_soff  = 0; /* This means async transfer... */
-       eregs->esp_stp   = 0;
-
-       /* Load FIFO with the actual SCSI command. */
-       for(i=0; i < SCptr->cmd_len; i++)
-               eregs->esp_fdata = SCptr->cmnd[i];
-
-       /* Make sure the dvma forwards the ESP interrupt. */
-       dregs->cond_reg = DMA_INT_ENAB;
-
-       /* Tell ESP to SELECT without asserting ATN. */
-       eregs->esp_cmd = ESP_CMD_SEL;
-       return;
-
-bad:
-       panic("esp: daaarrrkk starrr crashesss....");
-}
-
-/* Queue a SCSI command delivered from the mid-level Linux SCSI code. */
-int esp_queue(Scsi_Cmnd *SCpnt, void (*done)(Scsi_Cmnd *))
-{
-       struct Sparc_ESP *esp;
-       unsigned long flags;
-
-       save_flags(flags); cli();
-
-       /* Set up func ptr and initial driver cmd-phase. */
-       SCpnt->scsi_done = done;
-       SCpnt->SCp.phase = not_issued;
-
-       esp = (struct Sparc_ESP *) SCpnt->host->hostdata;
-
-       /* We use the scratch area. */
-       if(!SCpnt->use_sg) {
-               SCpnt->SCp.this_residual    = SCpnt->request_bufflen;
-               SCpnt->SCp.buffer           =
-                       (struct scatterlist *) SCpnt->request_buffer;
-               SCpnt->SCp.buffers_residual = 0;
-               SCpnt->SCp.Status           = CHECK_CONDITION;
-               SCpnt->SCp.Message          = 0;
-               SCpnt->SCp.have_data_in     = 0;
-               SCpnt->SCp.sent_command     = 0;
-               SCpnt->SCp.ptr = mmu_get_scsi_one((char *)SCpnt->SCp.buffer,
-                                                    SCpnt->SCp.this_residual,
-                                                    esp->edev->my_bus);
-       } else {
-#ifdef DEBUG_ESP_SG
-               printk("esp: sglist at %p with %d buffers\n",
-                      SCpnt->buffer, SCpnt->use_sg);
-#endif
-               SCpnt->SCp.buffer           = (struct scatterlist *) SCpnt->buffer;
-               SCpnt->SCp.buffers_residual = SCpnt->use_sg - 1;
-               SCpnt->SCp.this_residual    = SCpnt->SCp.buffer->length;
-               mmu_get_scsi_sgl((struct mmu_sglist *) SCpnt->SCp.buffer,
-                                SCpnt->SCp.buffers_residual,
-                                esp->edev->my_bus);
-               SCpnt->SCp.ptr              = (char *) SCpnt->SCp.buffer->alt_address;
-       }
-
-       /* Place into our queue. */
-       append_SC(&esp->issue_SC, SCpnt);
-
-       /* Run it now if we can */
-       if(!esp->current_SC)
-               esp_exec_cmd(esp);
-
-       restore_flags(flags);
-       return 0;
-}
-
-/* Only queuing supported in this ESP driver. */
-int esp_command(Scsi_Cmnd *SCpnt)
-{
-       ESPLOG(("esp: esp_command() called...\n"));
-       return -1;
-}
-
-/* Abort a command.  Those that are on the bus force a SCSI bus
- * reset.
- */
-int esp_abort(Scsi_Cmnd *SCpnt)
-{
-       ESPLOG(("esp_abort: Not implemented yet\n"));
-       return SCSI_ABORT_ERROR;
-}
-
-/* Reset ESP chip, reset hanging bus, then kill active and
- * disconnected commands for targets without soft reset.
- */
-int esp_reset(Scsi_Cmnd *SCptr, unsigned int how)
-{
-       ESPLOG(("esp_reset: Not implemented yet\n"));
-       return SCSI_RESET_ERROR;
-}
-
-/* Internal ESP done function. */
-static inline void esp_done(struct Sparc_ESP *esp, int error)
-{
-       unsigned long flags;
-       Scsi_Cmnd *done_SC;
-
-       if(esp->current_SC) {
-               /* Critical section... */
-               save_flags(flags); cli();
-               done_SC = esp->current_SC;
-               esp->current_SC = NULL;
-               /* Free dvma entry. */
-               if(!done_SC->use_sg) {
-                       mmu_release_scsi_one(done_SC->SCp.ptr,
-                                               done_SC->SCp.this_residual,
-                                               esp->edev->my_bus);
-               } else {
-                       struct scatterlist *scl = (struct scatterlist *)done_SC->buffer;
-#ifdef DEBUG_ESP_SG
-                       printk("esp: unmapping sg ");
-#endif
-                       mmu_release_scsi_sgl((struct mmu_sglist *) scl,
-                                            done_SC->use_sg - 1,
-                                            esp->edev->my_bus);
-#ifdef DEBUG_ESP_SG
-                       printk("done.\n");
-#endif
-               }
-               done_SC->result = error;
-               if(done_SC->scsi_done)
-                       done_SC->scsi_done(done_SC);
-               else
-                       panic("esp: esp->current_SC->scsi_done() == NULL");
-
-               /* Bus is free, issue any commands in the queue. */
-               if(esp->issue_SC)
-                       esp_exec_cmd(esp);
-
-               restore_flags(flags);
-               /* End of critical section... */
-       } else
-               panic("esp: done() called with NULL esp->current_SC");
-}
-
-#ifdef THREADED_ESP_DRIVER /* planning stage... */
-
-/* With multiple lots of commands being processed I frequently
- * see a situation where we see galloping esp herds.  esp_done()
- * wakes the entire world up and each interrupt causes a reschedule.
- * This kernel thread fixes some of these unwanted effects during
- * IO intensive activity.... I hope...
- */
-
-static void esp_kernel_thread(void *opaque)
-{
-       struct Sparc_ESP *esp = opaque;
-
-       for(;;) {
-               unsigned long flags;
-
-               while(esp->eatme_SC) {
-                       struct Scsi_Cmnd *SCpnt;
-
-                       SCpnt = remove_first_SC(esp->eatme_SC);
-                       esp_done(esp, error, SCpnt);
-               }
-               sleep();
-       }
-}
-#endif
-
-/* Read the interrupt status registers on this ESP board */
-static inline void esp_updatesoft(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
-{
-       /* Update our software copies of the three ESP status
-        * registers for this ESP.  Be careful, reading the
-        * ESP interrupt register clears the status and sequence
-        * step registers (unlatches them, you get the idea).
-        * So read the interrupt register last.
-        */
-
-       esp->seqreg = eregs->esp_sstep;
-       esp->sreg = eregs->esp_status;
-
-       /* Supposedly, the ESP100A and above assert the highest
-        * bit in the status register if an interrupt is pending.
-        * I've never seen this work properly, so let's clear it
-        * manually while we are here.  If I see any esp chips
-        * for which this bit is reliable I will conditionalize
-        * this.  However, I don't see what this extra bit can
-        * buy me with all the tests I'll have to place all over
-        * the code to actually use it when I 'can'.  Plus the
-        * 'pending interrupt' condition can more than reliably
-        * be obtained from the DVMA control register.
-        *
-        * "Broken hardware"  -Linus
-        */
-       esp->sreg &= (~ESP_STAT_INTR);
-       esp->ireg = eregs->esp_intrpt;   /* Must be last or we lose */
-}
-
-/* #define ESP_IRQ_TRACE */
-
-#ifdef ESP_IRQ_TRACE
-#define ETRACE(foo)  printk foo
-#else
-#define ETRACE(foo)
-#endif
-
-static char last_fflags, last_status, last_msg;
-
-/* Main interrupt handler for an esp adapter. */
-static inline void esp_handle(struct Sparc_ESP *esp)
-{
-       struct sparc_dma_registers *dregs;
-       struct Sparc_ESP_regs *eregs;
-       Scsi_Cmnd *SCptr;
-
-       eregs = esp->eregs;
-       dregs = esp->dregs;
-       SCptr = esp->current_SC;
-
-       DMA_IRQ_ENTRY(esp->dma, dregs);
-       esp_updatesoft(esp, eregs);
-
-       ETRACE(("ESPIRQ: <%2x,%2x,%2x> --> ", esp->ireg, esp->sreg, esp->seqreg));
-
-       /* Check for errors. */
-       if(!SCptr)
-               panic("esp_handle: current_SC == penguin within interrupt!");
-
-       /* At this point in time, this esp driver should not see
-        * scsibus resets, parity errors, or gross errors unless
-        * something truly terrible happens which we are not ready
-        * to properly recover from yet.
-        */
-       if((esp->ireg & (ESP_INTR_SR | ESP_INTR_IC)) ||
-          (esp->sreg & (ESP_STAT_PERR | ESP_STAT_SPAM))) {
-               printk("esp: really bad error detected\n");
-               printk("esp: intr<%2x> stat<%2x> seq<%2x>",
-                      esp->ireg, esp->sreg, esp->seqreg);
-               printk("esp: SCptr->SCp.phase = %d\n", SCptr->SCp.phase);
-               panic("esp: cannot continue\n");
-       }
-       if(dregs->cond_reg & DMA_HNDL_ERROR) {
-               printk("esp: DMA shows an error cond_reg<%08lx> addr<%p>\n",
-                      dregs->cond_reg, dregs->st_addr);
-               printk("esp: intr<%2x> stat<%2x> seq<%2x>",
-                      esp->ireg, esp->sreg, esp->seqreg);
-               printk("esp: SCptr->SCp.phase = %d\n", SCptr->SCp.phase);
-               panic("esp: cannot continue\n");
-       }
-       if(esp->sreg & ESP_STAT_PERR) {
-               printk("esp: SCSI bus parity error\n");
-               printk("esp: intr<%2x> stat<%2x> seq<%2x>",
-                      esp->ireg, esp->sreg, esp->seqreg);
-               printk("esp: SCptr->SCp.phase = %d\n", SCptr->SCp.phase);
-               panic("esp: cannot continue\n");
-       }
-
-       /* Service interrupt. */
-       switch(SCptr->SCp.phase) {
-       case not_issued:
-               panic("Unexpected ESP interrupt, current_SC not issued.");
-               break;
-       case in_selection:
-               if(esp->ireg & ESP_INTR_RSEL) {
-                       /* XXX Some day XXX */
-                       panic("ESP penguin reselected in async mode.");
-               } else if(esp->ireg & ESP_INTR_DC) {
-                       /* Either we are scanning the bus and no-one
-                        * lives at this target or it didn't respond.
-                        */
-                       ETRACE(("DISCONNECT\n"));
-#ifdef THREADED_ESP_DRIVER
-                       append_SC(esp->eatme_SC, esp->current_SC);
-                       esp->current_SC = 0;
-                       wake_up(esp_kernel_thread);
-#else
-                       esp_done(esp, (DID_NO_CONNECT << 16));
-#endif
-                       goto esp_handle_done;
-               } else if((esp->ireg & (ESP_INTR_FDONE | ESP_INTR_BSERV)) ==
-                         (ESP_INTR_FDONE | ESP_INTR_BSERV)) {
-                       /* Selection successful, check the sequence step. */
-                       /* XXX I know, I know... add error recovery.  XXX */
-                       switch(esp->seqreg & ESP_STEP_VBITS) {
-                       case ESP_STEP_NCMD:
-                               panic("esp: penguin didn't enter cmd phase.");
-                               break;
-                       case ESP_STEP_PPC:
-                               panic("esp: penguin prematurely changed from cmd phase.");
-                               break;
-                       case ESP_STEP_FINI:
-                               /* At the completion of every command
-                                * or message-out phase, we _must_
-                                * unlatch the fifo-flags register
-                                * with an ESP nop command.
-                                */
-                               eregs->esp_cmd = ESP_CMD_NULL;
-
-                               /* Selection/Command sequence completed.  We
-                                * (at least for this driver) will be in
-                                * either one of the data phases or status
-                                * phase, check the status register to find
-                                * out.
-                                */
-                               switch(esp->sreg & ESP_STAT_PMASK) {
-                               default:
-                                       printk("esp: Not datain/dataout/status.\n");
-                                       panic("esp: penguin phase transition after selection.");
-                                       break;
-                               case ESP_DOP:
-                                       /* Data out phase. */
-                                       dregs->cond_reg |= DMA_FIFO_INV;
-                                       while(dregs->cond_reg & DMA_FIFO_ISDRAIN)
-                                               barrier();
-                                       SCptr->SCp.phase = in_dataout;
-#ifdef DEBUG_ESP_SG
-                                       if(SCptr->use_sg)
-                                               printk("esp: sg-start <%p,%d>",
-                                                      SCptr->SCp.ptr,
-                                                      SCptr->SCp.this_residual);
-#endif
-                                       eregs->esp_tclow = SCptr->SCp.this_residual;
-                                       eregs->esp_tcmed = (SCptr->SCp.this_residual>>8);
-                                       eregs->esp_cmd = (ESP_CMD_DMA | ESP_CMD_NULL);
-
-                                       /* This is either the one buffer dvma ptr,
-                                        * or the first one in the scatter gather
-                                        * list.  Check out esp_queue to see how
-                                        * this is set up.
-                                        */
-                                       dregs->st_addr = SCptr->SCp.ptr;
-                                       dregs->cond_reg &= ~(DMA_ST_WRITE);
-                                       dregs->cond_reg |= (DMA_ENABLE | DMA_INT_ENAB);
-                                       eregs->esp_cmd = (ESP_CMD_DMA | ESP_CMD_TI);
-                                       ETRACE(("DATA_OUT\n"));
-                                       goto esp_handle_done;
-                               case ESP_DIP:
-                                       /* Data in phase. */
-                                       dregs->cond_reg |= DMA_FIFO_INV;
-                                       while(dregs->cond_reg & DMA_FIFO_ISDRAIN)
-                                               barrier();
-                                       SCptr->SCp.phase = in_datain;
-#ifdef DEBUG_ESP_SG
-                                       if(SCptr->use_sg)
-                                               printk("esp: sg-start <%p,%d>",
-                                                      SCptr->SCp.ptr,
-                                                      SCptr->SCp.this_residual);
-#endif
-                                       eregs->esp_tclow = SCptr->SCp.this_residual;
-                                       eregs->esp_tcmed = (SCptr->SCp.this_residual>>8);
-                                       eregs->esp_cmd = (ESP_CMD_DMA | ESP_CMD_NULL);
-
-                                       /* This is either the one buffer dvma ptr,
-                                        * or the first one in the scatter gather
-                                        * list.  Check out esp_queue to see how
-                                        * this is set up.
-                                        */
-                                       dregs->st_addr = SCptr->SCp.ptr;
-                                       dregs->cond_reg |= (DMA_ENABLE | DMA_ST_WRITE | DMA_INT_ENAB);
-                                       eregs->esp_cmd = (ESP_CMD_DMA | ESP_CMD_TI);
-                                       ETRACE(("DATA_IN\n"));
-                                       goto esp_handle_done;
-                               case ESP_STATP:
-                                       /* Status phase. */
-                                       SCptr->SCp.phase = in_status;
-                                       eregs->esp_cmd = ESP_CMD_ICCSEQ;
-                                       ETRACE(("STATUS\n"));
-                                       goto esp_handle_done; /* Wait for message. */
-                               };
-                       };
-               } else if(esp->ireg & ESP_INTR_FDONE) {
-                       /* I'd like to investigate why this happens... */
-                       ESPLOG(("esp: This is weird, halfway through "));
-                       ESPLOG(("selection, trying to continue anyways.\n"));
-                       goto esp_handle_done;
-               } else {
-                       panic("esp: Did not get bus service during selection.");
-                       goto esp_handle_done;
-               }
-               panic("esp: Mr. Potatoe Head is on the loose!");
-
-       case in_datain:
-               /* Drain the fifo for writes to memory. */
-               switch(esp->dma->revision) {
-               case dvmarev0:
-               case dvmarev1:
-               case dvmarevplus:
-               case dvmarev2:
-               case dvmarev3:
-                       /* Force a drain. */
-                       dregs->cond_reg |= DMA_FIFO_STDRAIN;
-
-                       /* fall through */
-               case dvmaesc1:
-                       /* Wait for the fifo to drain completely. */
-                       while(dregs->cond_reg & DMA_FIFO_ISDRAIN)
-                               barrier();
-                       break;
-               };
-
-       case in_dataout:
-               dregs->cond_reg &= ~DMA_ENABLE;
-
-               /* We may be pipelining an sg-list. */
-               if(SCptr->use_sg) {
-                       if(SCptr->SCp.buffers_residual) {
-                               /* If we do not see a BUS SERVICE interrupt
-                                * at this point, or we see that we have left
-                                * the current data phase, then we lose.
-                                */
-                               if(!(esp->ireg & ESP_INTR_BSERV) ||
-                                  ((esp->sreg & ESP_STAT_PMASK) > 1))
-                                       panic("esp: Aiee penguin on the SCSI-bus.");
-
-                               ++SCptr->SCp.buffer;
-                               --SCptr->SCp.buffers_residual;
-                               SCptr->SCp.this_residual = SCptr->SCp.buffer->length;
-                               SCptr->SCp.ptr = SCptr->SCp.buffer->alt_address;
-
-#ifdef DEBUG_ESP_SG
-                               printk("<%p,%d> ", SCptr->SCp.ptr,
-                                      SCptr->SCp.this_residual);
-#endif
-
-                               /* Latch in new esp counters... */
-                               eregs->esp_tclow = SCptr->SCp.this_residual;
-                               eregs->esp_tcmed = (SCptr->SCp.this_residual>>8);
-                               eregs->esp_cmd = (ESP_CMD_DMA | ESP_CMD_NULL);
-
-                               /* Reload DVMA gate array with new vaddr and enab. */
-                               dregs->st_addr = SCptr->SCp.ptr;
-                               dregs->cond_reg |= DMA_ENABLE;
-
-                               /* Tell the esp to start transferring. */
-                               eregs->esp_cmd = (ESP_CMD_DMA | ESP_CMD_TI);
-                               goto esp_handle_done;
-                       }
-#ifdef DEBUG_ESP_SG
-                       printk("done.\n");
-#endif
-               }
-               /* Take a look at what happened. */
-               if(esp->ireg & ESP_INTR_DC) {
-                       panic("esp: target disconnects during data transfer.");
-                       goto esp_handle_done;
-               } else if(esp->ireg & ESP_INTR_BSERV) {
-                       if((esp->sreg & ESP_STAT_PMASK) != ESP_STATP) {
-                               panic("esp: Not status phase after data phase.");
-                               goto esp_handle_done;
-                       }
-                       SCptr->SCp.phase = in_status;
-                       eregs->esp_cmd = ESP_CMD_ICCSEQ;
-                       ETRACE(("STATUS\n"));
-                       goto esp_handle_done; /* Wait for message. */
-               } else {
-                       printk("esp: did not get bus service after data transfer.");
-                       printk("esp_status: intr<%2x> stat<%2x> seq<%2x>\n",
-                              esp->ireg, esp->sreg, esp->seqreg);
-                       panic("esp: penguin data transfer.");
-                       goto esp_handle_done;
-               }
-       case in_status:
-               if(esp->ireg & ESP_INTR_DC) {
-                       panic("esp: penguin disconnects in status phase.");
-                       goto esp_handle_done;
-               } else if (esp->ireg & ESP_INTR_FDONE) {
-                       /* Status and Message now sit in the fifo for us. */
-                       last_fflags = eregs->esp_fflags;
-                       SCptr->SCp.phase   = in_finale;
-                       last_status = SCptr->SCp.Status  = eregs->esp_fdata;
-                       last_msg = SCptr->SCp.Message = eregs->esp_fdata;
-                       eregs->esp_cmd = ESP_CMD_MOK;
-                       ETRACE(("FINALE\n"));
-                       goto esp_handle_done;
-               } else {
-                       panic("esp: penguin status phase.");
-               }
-       case in_finale:
-               if(esp->ireg & ESP_INTR_BSERV) {
-                       panic("esp: penguin doesn't disconnect after status msg-ack.");
-                       goto esp_handle_done;
-               } else if(esp->ireg & ESP_INTR_DC) {
-                       /* Nexus is complete. */
-#ifdef THREADED_ESP_DRIVER
-                       append_SC(esp->eatme_SC, esp->current_SC);
-                       esp->current_SC = 0;
-                       wake_up(esp_kernel_thread);
-#else
-                       esp_done(esp, ((SCptr->SCp.Status & 0xff) |
-                                ((SCptr->SCp.Message & 0xff) << 8) |
-                                (DID_OK << 16)));
-#endif
-                       ETRACE(("NEXUS_COMPLETE\n"));
-                       goto esp_handle_done;
-               } else {
-                       printk("esp: wacky state while in in_finale phase.\n");
-                       printk("esp_status: intr<%2x> stat<%2x> seq<%2x>\n",
-                              esp->ireg, esp->sreg, esp->seqreg);
-                       panic("esp: penguin esp state.");
-                       goto esp_handle_done;
-               }
-       default:
-               panic("esp: detected penguin phase.");
-               goto esp_handle_done;
-       }
-       panic("esp: Heading to the promised land.");
-
-esp_handle_done:
-       DMA_IRQ_EXIT(esp->dma, dregs);
-       return;
-}
-
-static void esp_intr(int irq, void *dev_id, struct pt_regs *pregs)
-{
-       struct Sparc_ESP *esp;
-
-       /* Handle all ESP interrupts showing */
-       for_each_esp(esp) {
-               if(DMA_IRQ_P(esp->dregs)) {
-                       esp_handle(esp);
-               }
-       }
-}
+/* esp.c:  EnhancedScsiProcessor Sun SCSI driver code.
+ *
+ * Copyright (C) 1995, 1998 David S. Miller (davem@caip.rutgers.edu)
+ */
+
+/* TODO:
+ *
+ * 1) Maybe disable parity checking in config register one for SCSI1
+ *    targets.  (Gilmore says parity error on the SBus can lock up
+ *    old sun4c's)
+ * 2) Add support for DMA2 pipelining.
+ * 3) Add tagged queueing.
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/malloc.h>
+#include <linux/blk.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+
+#include "scsi.h"
+#include "hosts.h"
+#include "esp.h"
+
+#include <asm/sbus.h>
+#include <asm/dma.h>
+#include <asm/system.h>
+#include <asm/machines.h>
+#include <asm/ptrace.h>
+#include <asm/pgtable.h>
+#include <asm/oplib.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/idprom.h>
+
+#define DEBUG_ESP
+/* #define DEBUG_ESP_HME */
+/* #define DEBUG_ESP_DATA */
+/* #define DEBUG_ESP_QUEUE */
+/* #define DEBUG_ESP_DISCONNECT */
+/* #define DEBUG_ESP_STATUS */
+/* #define DEBUG_ESP_PHASES */
+/* #define DEBUG_ESP_WORKBUS */
+/* #define DEBUG_STATE_MACHINE */
+/* #define DEBUG_ESP_CMDS */
+/* #define DEBUG_ESP_IRQS */
+/* #define DEBUG_SDTR */
+/* #define DEBUG_ESP_SG */
+
+/* Use the following to sprinkle debugging messages in a way which
+ * suits you if combinations of the above become too verbose when
+ * trying to track down a specific problem.
+ */
+/* #define DEBUG_ESP_MISC */
+
+#if defined(DEBUG_ESP)
+#define ESPLOG(foo)  printk foo
+#else
+#define ESPLOG(foo)
+#endif /* (DEBUG_ESP) */
+
+#if defined(DEBUG_ESP_HME)
+#define ESPHME(foo)  printk foo
+#else
+#define ESPHME(foo)
+#endif
+
+#if defined(DEBUG_ESP_DATA)
+#define ESPDATA(foo)  printk foo
+#else
+#define ESPDATA(foo)
+#endif
+
+#if defined(DEBUG_ESP_QUEUE)
+#define ESPQUEUE(foo)  printk foo
+#else
+#define ESPQUEUE(foo)
+#endif
+
+#if defined(DEBUG_ESP_DISCONNECT)
+#define ESPDISC(foo)  printk foo
+#else
+#define ESPDISC(foo)
+#endif
+
+#if defined(DEBUG_ESP_STATUS)
+#define ESPSTAT(foo)  printk foo
+#else
+#define ESPSTAT(foo)
+#endif
+
+#if defined(DEBUG_ESP_PHASES)
+#define ESPPHASE(foo)  printk foo
+#else
+#define ESPPHASE(foo)
+#endif
+
+#if defined(DEBUG_ESP_WORKBUS)
+#define ESPBUS(foo)  printk foo
+#else
+#define ESPBUS(foo)
+#endif
+
+#if defined(DEBUG_ESP_IRQS)
+#define ESPIRQ(foo)  printk foo
+#else
+#define ESPIRQ(foo)
+#endif
+
+#if defined(DEBUG_SDTR)
+#define ESPSDTR(foo)  printk foo
+#else
+#define ESPSDTR(foo)
+#endif
+
+#if defined(DEBUG_ESP_MISC)
+#define ESPMISC(foo)  printk foo
+#else
+#define ESPMISC(foo)
+#endif
+
+/* Command phase enumeration. */
+enum {
+       not_issued    = 0x00,  /* Still in the issue_SC queue.          */
+
+       /* Various forms of selecting a target. */
+#define in_slct_mask    0x10
+       in_slct_norm  = 0x10,  /* ESP is arbitrating, normal selection  */
+       in_slct_stop  = 0x11,  /* ESP will select, then stop with IRQ   */
+       in_slct_msg   = 0x12,  /* select, then send a message           */
+       in_slct_tag   = 0x13,  /* select and send tagged queue msg      */
+       in_slct_sneg  = 0x14,  /* select and acquire sync capabilities  */
+
+       /* Any post selection activity. */
+#define in_phases_mask  0x20
+       in_datain     = 0x20,  /* Data is transferring from the bus     */
+       in_dataout    = 0x21,  /* Data is transferring to the bus       */
+       in_data_done  = 0x22,  /* Last DMA data operation done (maybe)  */
+       in_msgin      = 0x23,  /* Eating message from target            */
+       in_msgincont  = 0x24,  /* Eating more msg bytes from target     */
+       in_msgindone  = 0x25,  /* Decide what to do with what we got    */
+       in_msgout     = 0x26,  /* Sending message to target             */
+       in_msgoutdone = 0x27,  /* Done sending msg out                  */
+       in_cmdbegin   = 0x28,  /* Sending cmd after abnormal selection  */
+       in_cmdend     = 0x29,  /* Done sending slow cmd                 */
+       in_status     = 0x2a,  /* Was in status phase, finishing cmd    */
+       in_freeing    = 0x2b,  /* freeing the bus for cmd cmplt or disc */
+       in_the_dark   = 0x2c,  /* Don't know what bus phase we are in   */
+
+       /* Special states, ie. not normal bus transitions... */
+#define in_spec_mask    0x80
+       in_abortone   = 0x80,  /* Aborting one command currently        */
+       in_abortall   = 0x81,  /* Blowing away all commands we have     */
+       in_resetdev   = 0x82,  /* SCSI target reset in progress         */
+       in_resetbus   = 0x83,  /* SCSI bus reset in progress            */
+       in_tgterror   = 0x84,  /* Target did something stupid           */
+};
+
+enum {
+       /* Zero has special meaning, see skipahead[12]. */
+/*0*/  do_never,
+
+/*1*/  do_phase_determine,
+/*2*/  do_reset_bus,
+/*3*/  do_reset_complete,
+/*4*/  do_work_bus,
+/*5*/  do_intr_end
+};
+
+struct proc_dir_entry proc_scsi_esp = {
+       PROC_SCSI_ESP, 3, "esp",
+       S_IFDIR | S_IRUGO | S_IXUGO, 2
+};
+
+/* The master ring of all esp hosts we are managing in this driver. */
+static struct Sparc_ESP *espchain;
+static int esps_running = 0;
+
+/* Forward declarations. */
+static void esp_intr(int irq, void *dev_id, struct pt_regs *pregs);
+#ifndef __sparc_v9__
+static void esp_intr_4d(int irq, void *dev_id, struct pt_regs *pregs);
+#endif
+
+/* Debugging routines */
+struct esp_cmdstrings {
+       unchar cmdchar;
+       char *text;
+} esp_cmd_strings[] = {
+       /* Miscellaneous */
+       { ESP_CMD_NULL, "ESP_NOP", },
+       { ESP_CMD_FLUSH, "FIFO_FLUSH", },
+       { ESP_CMD_RC, "RSTESP", },
+       { ESP_CMD_RS, "RSTSCSI", },
+       /* Disconnected State Group */
+       { ESP_CMD_RSEL, "RESLCTSEQ", },
+       { ESP_CMD_SEL, "SLCTNATN", },
+       { ESP_CMD_SELA, "SLCTATN", },
+       { ESP_CMD_SELAS, "SLCTATNSTOP", },
+       { ESP_CMD_ESEL, "ENSLCTRESEL", },
+       { ESP_CMD_DSEL, "DISSELRESEL", },
+       { ESP_CMD_SA3, "SLCTATN3", },
+       { ESP_CMD_RSEL3, "RESLCTSEQ", },
+       /* Target State Group */
+       { ESP_CMD_SMSG, "SNDMSG", },
+       { ESP_CMD_SSTAT, "SNDSTATUS", },
+       { ESP_CMD_SDATA, "SNDDATA", },
+       { ESP_CMD_DSEQ, "DISCSEQ", },
+       { ESP_CMD_TSEQ, "TERMSEQ", },
+       { ESP_CMD_TCCSEQ, "TRGTCMDCOMPSEQ", },
+       { ESP_CMD_DCNCT, "DISC", },
+       { ESP_CMD_RMSG, "RCVMSG", },
+       { ESP_CMD_RCMD, "RCVCMD", },
+       { ESP_CMD_RDATA, "RCVDATA", },
+       { ESP_CMD_RCSEQ, "RCVCMDSEQ", },
+       /* Initiator State Group */
+       { ESP_CMD_TI, "TRANSINFO", },
+       { ESP_CMD_ICCSEQ, "INICMDSEQCOMP", },
+       { ESP_CMD_MOK, "MSGACCEPTED", },
+       { ESP_CMD_TPAD, "TPAD", },
+       { ESP_CMD_SATN, "SATN", },
+       { ESP_CMD_RATN, "RATN", },
+};
+#define NUM_ESP_COMMANDS  ((sizeof(esp_cmd_strings)) / (sizeof(struct esp_cmdstrings)))
+
+/* Print textual representation of an ESP command */
+static inline void esp_print_cmd(unchar espcmd)
+{
+       unchar dma_bit = espcmd & ESP_CMD_DMA;
+       int i;
+
+       espcmd &= ~dma_bit;
+       for(i=0; i<NUM_ESP_COMMANDS; i++)
+               if(esp_cmd_strings[i].cmdchar == espcmd)
+                       break;
+       if(i==NUM_ESP_COMMANDS)
+               printk("ESP_Unknown");
+       else
+               printk("%s%s", esp_cmd_strings[i].text,
+                      ((dma_bit) ? "+DMA" : ""));
+}
+
+/* Print the status register's value */
+static inline void esp_print_statreg(unchar statreg)
+{
+       unchar phase;
+
+       printk("STATUS<");
+       phase = statreg & ESP_STAT_PMASK;
+       printk("%s,", (phase == ESP_DOP ? "DATA-OUT" :
+                      (phase == ESP_DIP ? "DATA-IN" :
+                       (phase == ESP_CMDP ? "COMMAND" :
+                        (phase == ESP_STATP ? "STATUS" :
+                         (phase == ESP_MOP ? "MSG-OUT" :
+                          (phase == ESP_MIP ? "MSG_IN" :
+                           "unknown")))))));
+       if(statreg & ESP_STAT_TDONE)
+               printk("TRANS_DONE,");
+       if(statreg & ESP_STAT_TCNT)
+               printk("TCOUNT_ZERO,");
+       if(statreg & ESP_STAT_PERR)
+               printk("P_ERROR,");
+       if(statreg & ESP_STAT_SPAM)
+               printk("SPAM,");
+       if(statreg & ESP_STAT_INTR)
+               printk("IRQ,");
+       printk(">");
+}
+
+/* Print the interrupt register's value */
+static inline void esp_print_ireg(unchar intreg)
+{
+       printk("INTREG< ");
+       if(intreg & ESP_INTR_S)
+               printk("SLCT_NATN ");
+       if(intreg & ESP_INTR_SATN)
+               printk("SLCT_ATN ");
+       if(intreg & ESP_INTR_RSEL)
+               printk("RSLCT ");
+       if(intreg & ESP_INTR_FDONE)
+               printk("FDONE ");
+       if(intreg & ESP_INTR_BSERV)
+               printk("BSERV ");
+       if(intreg & ESP_INTR_DC)
+               printk("DISCNCT ");
+       if(intreg & ESP_INTR_IC)
+               printk("ILL_CMD ");
+       if(intreg & ESP_INTR_SR)
+               printk("SCSI_BUS_RESET ");
+       printk(">");
+}
+
+/* Print the sequence step registers contents */
+static inline void esp_print_seqreg(unchar stepreg)
+{
+       stepreg &= ESP_STEP_VBITS;
+       printk("STEP<%s>",
+              (stepreg == ESP_STEP_ASEL ? "SLCT_ARB_CMPLT" :
+               (stepreg == ESP_STEP_SID ? "1BYTE_MSG_SENT" :
+                (stepreg == ESP_STEP_NCMD ? "NOT_IN_CMD_PHASE" :
+                 (stepreg == ESP_STEP_PPC ? "CMD_BYTES_LOST" :
+                  (stepreg == ESP_STEP_FINI4 ? "CMD_SENT_OK" :
+                   "UNKNOWN"))))));
+}
+
+static char *phase_string(int phase)
+{
+       switch(phase) {
+       case not_issued:
+               return "UNISSUED";
+       case in_slct_norm:
+               return "SLCTNORM";
+       case in_slct_stop:
+               return "SLCTSTOP";
+       case in_slct_msg:
+               return "SLCTMSG";
+       case in_slct_tag:
+               return "SLCTTAG";
+       case in_slct_sneg:
+               return "SLCTSNEG";
+       case in_datain:
+               return "DATAIN";
+       case in_dataout:
+               return "DATAOUT";
+       case in_data_done:
+               return "DATADONE";
+       case in_msgin:
+               return "MSGIN";
+       case in_msgincont:
+               return "MSGINCONT";
+       case in_msgindone:
+               return "MSGINDONE";
+       case in_msgout:
+               return "MSGOUT";
+       case in_msgoutdone:
+               return "MSGOUTDONE";
+       case in_cmdbegin:
+               return "CMDBEGIN";
+       case in_cmdend:
+               return "CMDEND";
+       case in_status:
+               return "STATUS";
+       case in_freeing:
+               return "FREEING";
+       case in_the_dark:
+               return "CLUELESS";
+       case in_abortone:
+               return "ABORTONE";
+       case in_abortall:
+               return "ABORTALL";
+       case in_resetdev:
+               return "RESETDEV";
+       case in_resetbus:
+               return "RESETBUS";
+       case in_tgterror:
+               return "TGTERROR";
+       default:
+               return "UNKNOWN";
+       };
+}
+
+#ifdef DEBUG_STATE_MACHINE
+static inline void esp_advance_phase(Scsi_Cmnd *s, int newphase)
+{
+       ESPLOG(("<%s>", phase_string(newphase)));
+       s->SCp.sent_command = s->SCp.phase;
+       s->SCp.phase = newphase;
+}
+#else
+#define esp_advance_phase(__s, __newphase) \
+       (__s)->SCp.sent_command = (__s)->SCp.phase; \
+       (__s)->SCp.phase = (__newphase);
+#endif
+
+#ifdef DEBUG_ESP_CMDS
+extern inline void esp_cmd(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                          unchar cmd)
+{
+       esp->espcmdlog[esp->espcmdent] = cmd;
+       esp->espcmdent = (esp->espcmdent + 1) & 31;
+       eregs->esp_cmd = cmd;
+}
+#else
+#define esp_cmd(__esp, __eregs, __cmd) (__eregs)->esp_cmd = (__cmd)
+#endif
+
+/* How we use the various Linux SCSI data structures for operation.
+ *
+ * struct scsi_cmnd:
+ *
+ *   We keep track of the syncronous capabilities of a target
+ *   in the device member, using sync_min_period and
+ *   sync_max_offset.  These are the values we directly write
+ *   into the ESP registers while running a command.  If offset
+ *   is zero the ESP will use asynchronous transfers.
+ *   If the borken flag is set we assume we shouldn't even bother
+ *   trying to negotiate for synchronous transfer as this target
+ *   is really stupid.  If we notice the target is dropping the
+ *   bus, and we have been allowing it to disconnect, we clear
+ *   the disconnect flag.
+ */
+
+
+/* Manipulation of the ESP command queues.  Thanks to the aha152x driver
+ * and its author, Juergen E. Fischer, for the methods used here.
+ * Note that these are per-ESP queues, not global queues like
+ * the aha152x driver uses.
+ */
+static inline void append_SC(Scsi_Cmnd **SC, Scsi_Cmnd *new_SC)
+{
+       Scsi_Cmnd *end;
+
+       new_SC->host_scribble = (unsigned char *) NULL;
+       if(!*SC)
+               *SC = new_SC;
+       else {
+               for(end=*SC;end->host_scribble;end=(Scsi_Cmnd *)end->host_scribble)
+                       ;
+               end->host_scribble = (unsigned char *) new_SC;
+       }
+}
+
+static inline void prepend_SC(Scsi_Cmnd **SC, Scsi_Cmnd *new_SC)
+{
+       new_SC->host_scribble = (unsigned char *) *SC;
+       *SC = new_SC;
+}
+
+static inline Scsi_Cmnd *remove_first_SC(Scsi_Cmnd **SC)
+{
+       Scsi_Cmnd *ptr;
+       ptr = *SC;
+       if(ptr)
+               *SC = (Scsi_Cmnd *) (*SC)->host_scribble;
+       return ptr;
+}
+
+static inline Scsi_Cmnd *remove_SC(Scsi_Cmnd **SC, int target, int lun)
+{
+       Scsi_Cmnd *ptr, *prev;
+
+       for(ptr = *SC, prev = NULL;
+           ptr && ((ptr->target != target) || (ptr->lun != lun));
+           prev = ptr, ptr = (Scsi_Cmnd *) ptr->host_scribble)
+               ;
+       if(ptr) {
+               if(prev)
+                       prev->host_scribble=ptr->host_scribble;
+               else
+                       *SC=(Scsi_Cmnd *)ptr->host_scribble;
+       }
+       return ptr;
+}
+
+/* Resetting various pieces of the ESP scsi driver chipset/buses. */
+static void esp_reset_dma(struct Sparc_ESP *esp)
+{
+       struct sparc_dma_registers *dregs = esp->dregs;
+       unsigned long flags;
+       int can_do_burst16, can_do_burst32, can_do_burst64;
+       int can_do_sbus64;
+
+       can_do_burst16 = esp->bursts & DMA_BURST16;
+       can_do_burst32 = esp->bursts & DMA_BURST32;
+       can_do_burst64 = 0;
+       can_do_sbus64 = 0;
+#ifdef __sparc_v9__
+       /* XXX Can sun4d do these too? */
+       can_do_burst64 = esp->bursts & DMA_BURST64;
+       can_do_sbus64 = 1;
+       mmu_set_sbus64(esp->edev, esp->bursts);
+#endif
+
+       /* Punt the DVMA into a known state. */
+       if(esp->dma->revision != dvmahme) {
+               dregs->cond_reg |= DMA_RST_SCSI;
+               dregs->cond_reg &= ~(DMA_RST_SCSI);
+       }
+       switch(esp->dma->revision) {
+       case dvmahme:
+               /* This is the HME DVMA gate array. */
+
+               save_flags(flags); cli(); /* I really hate this chip. */
+
+               dregs->cond_reg = DMA_RESET_FAS366;   /* Reset interface to FAS */
+               dregs->cond_reg = DMA_RST_SCSI;       /* Reset DVMA itself */
+
+               esp->prev_hme_dmacsr = (DMA_PARITY_OFF|DMA_2CLKS|DMA_SCSI_DISAB|DMA_INT_ENAB);
+               esp->prev_hme_dmacsr &= ~(DMA_ENABLE|DMA_ST_WRITE|DMA_BRST_SZ);
+
+               if(can_do_burst32)
+                       esp->prev_hme_dmacsr |= DMA_BRST32;
+               else if(can_do_burst64)
+                       esp->prev_hme_dmacsr |= DMA_BRST64;
+
+               if(can_do_sbus64)
+                       esp->prev_hme_dmacsr |= DMA_SCSI_SBUS64;
+
+               /* This chip is horrible. */
+               while(dregs->cond_reg & DMA_PEND_READ)
+                       udelay(1);
+
+               dregs->cond_reg = 0;
+
+               dregs->cond_reg = esp->prev_hme_dmacsr;
+
+               /* This is necessary to avoid having the SCSI channel
+                * engine lock up on us.
+                */
+               dregs->st_addr = 0;
+
+               restore_flags(flags);
+               break;
+       case dvmarev2:
+               /* This is the gate array found in the sun4m
+                * NCR SBUS I/O subsystem.
+                */
+               if(esp->erev != esp100)
+                       dregs->cond_reg |= DMA_3CLKS;
+               break;
+       case dvmarev3:
+               dregs->cond_reg &= ~(DMA_3CLKS);
+               dregs->cond_reg |= DMA_2CLKS;
+               if(can_do_burst32) {
+                       dregs->cond_reg &= ~(DMA_BRST_SZ);
+                       dregs->cond_reg |= DMA_BRST32;
+               }
+               break;
+       case dvmaesc1:
+               /* This is the DMA unit found on SCSI/Ether cards. */
+               dregs->cond_reg |= DMA_ADD_ENABLE;
+               dregs->cond_reg &= ~DMA_BCNT_ENAB;
+               if(!can_do_burst32 && can_do_burst16) {
+                       dregs->cond_reg |= DMA_ESC_BURST;
+               } else {
+                       dregs->cond_reg &= ~(DMA_ESC_BURST);
+               }
+               break;
+       default:
+               break;
+       };
+       DMA_INTSON(dregs);
+}
+
+/* Reset the ESP chip, _not_ the SCSI bus. */
+static void esp_reset_esp(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
+{
+       int family_code, version, i;
+       volatile int trash;
+
+       /* Now reset the ESP chip */
+       esp_cmd(esp, eregs, ESP_CMD_RC);
+       esp_cmd(esp, eregs, ESP_CMD_NULL | ESP_CMD_DMA);
+       esp_cmd(esp, eregs, ESP_CMD_NULL | ESP_CMD_DMA);
+
+       /* Reload the configuration registers */
+       eregs->esp_cfact = esp->cfact;
+       eregs->esp_stp   = esp->prev_stp = 0;
+       eregs->esp_soff  = esp->prev_soff = 0;
+       eregs->esp_timeo = esp->neg_defp;
+
+       /* This is the only point at which it is reliable to read
+        * the ID-code for a fast ESP chip variants.
+        */
+       esp->max_period = ((35 * esp->ccycle) / 1000);
+       if(esp->erev == fast) {
+               version = eregs->esp_uid;
+               family_code = (version & 0xf8) >> 3;
+               if(family_code == 0x02)
+                       esp->erev = fas236;
+               else if(family_code == 0x0a)
+                       esp->erev = fashme; /* Version is usually '5'. */
+               else
+                       esp->erev = fas100a;
+               ESPMISC(("esp%d: FAST chip is %s (family=%d, version=%d)\n",
+                        esp->esp_id,
+                        (esp->erev == fas236) ? "fas236" :
+                        ((esp->erev == fas100a) ? "fas100a" :
+                         "fasHME"), family_code, (version & 7)));
+
+               esp->min_period = ((4 * esp->ccycle) / 1000);
+       } else {
+               esp->min_period = ((5 * esp->ccycle) / 1000);
+       }
+       esp->max_period = (esp->max_period + 3)>>2;
+       esp->min_period = (esp->min_period + 3)>>2;
+
+       eregs->esp_cfg1  = esp->config1;
+       switch(esp->erev) {
+       case esp100:
+               /* nothing to do */
+               break;
+       case esp100a:
+               eregs->esp_cfg2 = esp->config2;
+               break;
+       case esp236:
+               /* Slow 236 */
+               eregs->esp_cfg2 = esp->config2;
+               eregs->esp_cfg3 = esp->prev_cfg3 = esp->config3[0];
+               break;
+       case fashme:
+               esp->config2 |= (ESP_CONFIG2_HME32 | ESP_CONFIG2_HMEFENAB);
+               /* fallthrough... */
+       case fas236:
+               /* Fast 236 or HME */
+               eregs->esp_cfg2 = esp->config2;
+               for(i=0; i<8; i++) {
+                       if(esp->erev == fashme) {
+                               unsigned char cfg3;
+
+                               cfg3 = ESP_CONFIG3_FCLOCK | ESP_CONFIG3_OBPUSH;
+                               if (esp->scsi_id >= 8)
+                                       cfg3 |= ESP_CONFIG3_IDBIT3;
+                               esp->config3[i] |= cfg3;
+                       } else {
+                               esp->config3[i] |= ESP_CONFIG3_FCLK;
+                       }
+               }
+               eregs->esp_cfg3 = esp->prev_cfg3 = esp->config3[0];
+               if(esp->erev == fashme) {
+                       esp->radelay = 80;
+               } else {
+                       if(esp->diff)
+                               esp->radelay = 0;
+                       else
+                               esp->radelay = 96;
+               }
+               break;
+       case fas100a:
+               /* Fast 100a */
+               eregs->esp_cfg2 = esp->config2;
+               for(i=0; i<8; i++)
+                       esp->config3[i] |= ESP_CONFIG3_FCLOCK;
+               eregs->esp_cfg3 = esp->prev_cfg3 = esp->config3[0];
+               esp->radelay = 32;
+               break;
+       default:
+               panic("esp: what could it be... I wonder...");
+               break;
+       };
+
+       /* Eat any bitrot in the chip */
+       trash = eregs->esp_intrpt;
+       udelay(100);
+}
+
+/* This places the ESP into a known state at boot time. */
+static void esp_bootup_reset(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
+{
+       volatile unchar trash;
+
+       /* Reset the DMA */
+       esp_reset_dma(esp);
+
+       /* Reset the ESP */
+       esp_reset_esp(esp, eregs);
+
+       /* Reset the SCSI bus, but tell ESP not to generate an irq */
+       eregs->esp_cfg1 |= ESP_CONFIG1_SRRDISAB;
+       esp_cmd(esp, eregs, ESP_CMD_RS);
+       udelay(400);
+       eregs->esp_cfg1 = esp->config1;
+
+       /* Eat any bitrot in the chip and we are done... */
+       trash = eregs->esp_intrpt;
+}
+
+int __init detect_one_esp
+(Scsi_Host_Template *tpnt, struct linux_sbus_device *esp_dev, struct linux_sbus_device *espdma,
+ struct linux_sbus *sbus, int id, int hme)
+{
+       struct Sparc_ESP *esp, *elink;
+       struct Scsi_Host *esp_host;
+       struct Sparc_ESP_regs *eregs;
+       struct sparc_dma_registers *dregs;
+       struct Linux_SBus_DMA *dma, *dlink;
+       unsigned int fmhz;
+       unchar ccf, bsizes, bsizes_more;
+       int esp_node, i;
+       
+       esp_host = scsi_register(tpnt, sizeof(struct Sparc_ESP));
+       if(!esp_host)
+               panic("Cannot register ESP SCSI host");
+       if(hme)
+               esp_host->max_id = 16;
+       esp = (struct Sparc_ESP *) esp_host->hostdata;
+       if(!esp)
+               panic("No esp in hostdata");
+       esp->ehost = esp_host;
+       esp->edev = esp_dev;
+       esp->esp_id = id;
+
+#ifdef __sparc_v9__
+       esp_host->unchecked_isa_dma = 1;
+#endif
+
+       /* Put into the chain of esp chips detected */
+       if(espchain) {
+               elink = espchain;
+               while(elink->next) elink = elink->next;
+               elink->next = esp;
+       } else {
+               espchain = esp;
+       }
+       esp->next = 0;
+
+       /* Get misc. prom information */
+#define ESP_IS_MY_DVMA(esp, dma)  \
+       (!dma->SBus_dev || \
+        ((esp->edev->my_bus == dma->SBus_dev->my_bus) && \
+          (esp->edev->slot == dma->SBus_dev->slot) && \
+         (!strcmp(dma->SBus_dev->prom_name, "dma") || \
+          !strcmp(dma->SBus_dev->prom_name, "espdma"))))
+
+       esp_node = esp_dev->prom_node;
+       prom_getstring(esp_node, "name", esp->prom_name,
+                      sizeof(esp->prom_name));
+       esp->prom_node = esp_node;
+       if(espdma) {
+               for_each_dvma(dlink) {
+                       if(dlink->SBus_dev == espdma)
+                               break;
+               }
+       } else {
+               for_each_dvma(dlink) {
+                       if(ESP_IS_MY_DVMA(esp, dlink) &&
+                          !dlink->allocated)
+                               break;
+               }
+       }
+#undef ESP_IS_MY_DVMA
+       /* If we don't know how to handle the dvma,
+        * do not use this device.
+        */
+       if(!dlink){
+               printk ("Cannot find dvma for ESP%d's SCSI\n",
+                       esp->esp_id);
+               scsi_unregister (esp_host);
+               return -1;
+       }
+       if (dlink->allocated){
+               printk ("esp%d: can't use my espdma\n",
+                       esp->esp_id);
+               scsi_unregister (esp_host);
+               return -1;
+       }
+       dlink->allocated = 1;
+       dma = dlink;
+       esp->dma = dma;
+       esp->dregs = dregs = dma->regs;
+
+       /* Map in the ESP registers from I/O space */
+       if(!hme) {
+               prom_apply_sbus_ranges(esp->edev->my_bus, 
+                                      esp->edev->reg_addrs,
+                                      1, esp->edev);
+
+               esp->eregs = eregs = (struct Sparc_ESP_regs *)
+               sparc_alloc_io(esp->edev->reg_addrs[0].phys_addr, 0,
+                              PAGE_SIZE, "ESP Registers",
+                              esp->edev->reg_addrs[0].which_io, 0x0);
+       } else {
+               /* On HME, two reg sets exist, first is DVMA,
+                * second is ESP registers.
+                */
+               esp->eregs = eregs = (struct Sparc_ESP_regs *)
+               sparc_alloc_io(esp->edev->reg_addrs[1].phys_addr, 0,
+                              PAGE_SIZE, "ESP Registers",
+                              esp->edev->reg_addrs[1].which_io, 0x0);
+       }
+       if(!eregs)
+               panic("ESP registers unmappable");
+       esp->esp_command =
+               sparc_dvma_malloc(16, "ESP DVMA Cmd Block",
+                                 &esp->esp_command_dvma);
+       if(!esp->esp_command || !esp->esp_command_dvma)
+               panic("ESP DVMA transport area unmappable");
+
+       /* Set up the irq's etc. */
+       esp->ehost->base = (unsigned char *) esp->eregs;
+       esp->ehost->io_port =
+               esp->edev->reg_addrs[0].phys_addr;
+       esp->ehost->n_io_port = (unsigned char)
+               esp->edev->reg_addrs[0].reg_size;
+       esp->ehost->irq = esp->irq = esp->edev->irqs[0];
+
+#ifndef __sparc_v9__
+       if (sparc_cpu_model != sun4d) {
+               /* Allocate the irq only if necessary */
+               for_each_esp(elink) {
+                       if((elink != esp) && (esp->irq == elink->irq)) {
+                               goto esp_irq_acquired; /* BASIC rulez */
+                       }
+               }
+               if(request_irq(esp->ehost->irq, esp_intr, SA_SHIRQ,
+                              "Sparc ESP SCSI", NULL))
+                       panic("Cannot acquire ESP irq line");
+esp_irq_acquired:
+               printk("esp%d: IRQ %d ", esp->esp_id, esp->ehost->irq);
+       } else {
+               if (request_irq(esp->ehost->irq, esp_intr_4d,
+                       SA_SHIRQ, "Sparc ESP SCSI", esp))
+                       panic("Cannot acquire ESP irq line");
+               printk("esp%d: IRQ %s ", esp->esp_id, __irq_itoa(esp->ehost->irq));
+       }
+#else
+       /* On Ultra we must always call request_irq for each
+        * esp, so that imap registers get setup etc.
+        */
+       if(request_irq(esp->ehost->irq, esp_intr,
+                      SA_SHIRQ, "Sparc ESP SCSI", esp))
+               panic("Cannot acquire ESP irq line");
+       printk("esp%d: IRQ %s ",
+              esp->esp_id, __irq_itoa(esp->ehost->irq));
+#endif
+
+       /* Figure out our scsi ID on the bus */
+       esp->scsi_id = prom_getintdefault(esp->prom_node,
+                                         "initiator-id",
+                                         -1);
+       if(esp->scsi_id == -1)
+               esp->scsi_id = prom_getintdefault(esp->prom_node,
+                                                 "scsi-initiator-id",
+                                                 -1);
+       if(esp->scsi_id == -1)
+               esp->scsi_id = (!esp->edev->my_bus) ? 7 :
+                       prom_getintdefault(esp->edev->my_bus->prom_node,
+                                          "scsi-initiator-id",
+                                          7);
+       esp->ehost->this_id = esp->scsi_id;
+       esp->scsi_id_mask = (1 << esp->scsi_id);
+
+       /* Check for differential SCSI-bus */
+       esp->diff = prom_getbool(esp->prom_node, "differential");
+       if(esp->diff)
+               printk("Differential ");
+
+       /* Check out the clock properties of the chip. */
+
+       /* This is getting messy but it has to be done
+        * correctly or else you get weird behavior all
+        * over the place.  We are trying to basically
+        * figure out three pieces of information.
+        *
+        * a) Clock Conversion Factor
+        *
+        *    This is a representation of the input
+        *    crystal clock frequency going into the
+        *    ESP on this machine.  Any operation whose
+        *    timing is longer than 400ns depends on this
+        *    value being correct.  For example, you'll
+        *    get blips for arbitration/selection during
+        *    high load or with multiple targets if this
+        *    is not set correctly.
+        *
+        * b) Selection Time-Out
+        *
+        *    The ESP isn't very bright and will arbitrate
+        *    for the bus and try to select a target
+        *    forever if you let it.  This value tells
+        *    the ESP when it has taken too long to
+        *    negotiate and that it should interrupt
+        *    the CPU so we can see what happened.
+        *    The value is computed as follows (from
+        *    NCR/Symbios chip docs).
+        *
+        *          (Time Out Period) *  (Input Clock)
+        *    STO = ----------------------------------
+        *          (8192) * (Clock Conversion Factor)
+        *
+        *    You usually want the time out period to be
+        *    around 250ms, I think we'll set it a little
+        *    bit higher to account for fully loaded SCSI
+        *    bus's and slow devices that don't respond so
+        *    quickly to selection attempts. (yeah, I know
+        *    this is out of spec. but there is a lot of
+        *    buggy pieces of firmware out there so bite me)
+        *
+        * c) Imperical constants for synchronous offset
+        *    and transfer period register values
+        *
+        *    This entails the smallest and largest sync
+        *    period we could ever handle on this ESP.
+        */
+
+       fmhz = prom_getintdefault(esp->prom_node,
+                                 "clock-frequency",
+                                 -1);
+       if(fmhz==-1)
+               fmhz = (!esp->edev->my_bus) ? 0 :
+                       prom_getintdefault(esp->edev->my_bus->prom_node,
+                                          "clock-frequency",
+                                          -1);
+       if(fmhz <= (5000000))
+               ccf = 0;
+       else
+               ccf = (((5000000 - 1) + (fmhz))/(5000000));
+       if(!ccf || ccf > 8) {
+               /* If we can't find anything reasonable,
+                * just assume 20MHZ.  This is the clock
+                * frequency of the older sun4c's where I've
+                * been unable to find the clock-frequency
+                * PROM property.  All other machines provide
+                * useful values it seems.
+                */
+               ccf = ESP_CCF_F4;
+               fmhz = (20000000);
+       }
+       if(ccf==(ESP_CCF_F7+1))
+               esp->cfact = ESP_CCF_F0;
+       else if(ccf == ESP_CCF_NEVER)
+               esp->cfact = ESP_CCF_F2;
+       else
+               esp->cfact = ccf;
+       esp->cfreq = fmhz;
+       esp->ccycle = ESP_MHZ_TO_CYCLE(fmhz);
+       esp->ctick = ESP_TICK(ccf, esp->ccycle);
+       esp->neg_defp = ESP_NEG_DEFP(fmhz, ccf);
+       esp->sync_defp = SYNC_DEFP_SLOW;
+       printk("SCSI ID %d Clk %dMHz CCF=%d TOut %d ",
+              esp->scsi_id, (fmhz / 1000000),
+              ccf, (int) esp->neg_defp);
+
+       /* Find the burst sizes this dma/sbus/esp supports. */
+       bsizes = prom_getintdefault(esp->prom_node, "burst-sizes", 0xff);
+       bsizes &= 0xff;
+       if(espdma) {
+               bsizes_more = prom_getintdefault(
+                                 espdma->prom_node,
+                                 "burst-sizes", 0xff);
+               if(bsizes_more != 0xff)
+                       bsizes &= bsizes_more;
+       }
+       if (esp->edev->my_bus) {
+               bsizes_more = prom_getintdefault(esp->edev->my_bus->prom_node,
+                                                "burst-sizes", 0xff);
+               if(bsizes_more != 0xff)
+                       bsizes &= bsizes_more;
+       }
+
+       if(bsizes == 0xff || (bsizes & DMA_BURST16)==0 ||
+          (bsizes & DMA_BURST32)==0)
+               bsizes = (DMA_BURST32 - 1);
+
+       esp->bursts = bsizes;
+
+       /* Probe the revision of this esp */
+       esp->config1 = (ESP_CONFIG1_PENABLE | (esp->scsi_id & 7));
+       esp->config2 = (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY);
+       eregs->esp_cfg2 = esp->config2;
+       if((eregs->esp_cfg2 & ~(ESP_CONFIG2_MAGIC)) !=
+          (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY)) {
+               printk("NCR53C90(esp100)\n");
+               esp->erev = esp100;
+       } else {
+               eregs->esp_cfg2 = esp->config2 = 0;
+               eregs->esp_cfg3 = 0;
+               eregs->esp_cfg3 = esp->prev_cfg3 = esp->config3[0] = 5;
+               if(eregs->esp_cfg3 != 5) {
+                       printk("NCR53C90A(esp100a)\n");
+                       esp->erev = esp100a;
+               } else {
+                       int target;
+
+                       for(target=0; target<8; target++)
+                               esp->config3[target] = 0;
+                       eregs->esp_cfg3 = esp->prev_cfg3 = 0;
+                       if(ccf > ESP_CCF_F5) {
+                               printk("NCR53C9XF(espfast)\n");
+                               esp->erev = fast;
+                               eregs->esp_cfg2 = esp->config2 = 0;
+                               esp->sync_defp = SYNC_DEFP_FAST;
+                       } else {
+                               printk("NCR53C9x(esp236)\n");
+                               esp->erev = esp236;
+                               eregs->esp_cfg2 = esp->config2 = 0;
+                       }
+               }
+       }                               
+
+       /* Initialize the command queues */
+       esp->current_SC = 0;
+       esp->disconnected_SC = 0;
+       esp->issue_SC = 0;
+
+       /* Clear the state machines. */
+       esp->targets_present = 0;
+       esp->resetting_bus = 0;
+       esp->snip = 0;
+       esp->targets_present = 0;
+       for(i = 0; i < 32; i++)
+               esp->espcmdlog[i] = 0;
+       esp->espcmdent = 0;
+       for(i = 0; i < 16; i++) {
+               esp->cur_msgout[i] = 0;
+               esp->cur_msgin[i] = 0;
+       }
+       esp->prevmsgout = esp->prevmsgin = 0;
+       esp->msgout_len = esp->msgin_len = 0;
+
+       /* Clear the one behind caches to hold unmatchable values. */
+       esp->prev_soff = esp->prev_stp = esp->prev_cfg3 = 0xff;
+       esp->prev_hme_dmacsr = 0xffffffff;
+
+       /* Reset the thing before we try anything... */
+       esp_bootup_reset(esp, eregs);
+
+       return 0;
+}
+
+/* Detecting ESP chips on the machine.  This is the simple and easy
+ * version.
+ */
+
+#ifdef CONFIG_SUN4
+
+#include <asm/sun4paddr.h>
+
+int __init esp_detect(Scsi_Host_Template *tpnt)
+{
+       static struct linux_sbus_device esp_dev;
+       int esps_in_use = 0;
+
+       espchain = 0;
+
+       if(sun4_esp_physaddr) {
+               memset (&esp_dev, 0, sizeof(esp_dev));
+               esp_dev.reg_addrs[0].phys_addr = sun4_esp_physaddr;
+               esp_dev.irqs[0] = 4;
+
+               if (!detect_one_esp(tpnt, &esp_dev, NULL, NULL, 0, 0))
+                       esps_in_use++;
+               printk("ESP: Total of 1 ESP hosts found, %d actually in use.\n", esps_in_use);
+               esps_running = esps_in_use;
+       }
+       return esps_in_use;
+}
+
+#else /* !CONFIG_SUN4 */
+
+int __init esp_detect(Scsi_Host_Template *tpnt)
+{
+       struct linux_sbus *sbus;
+       struct linux_sbus_device *esp_dev, *sbdev_iter;
+       int nesps = 0, esps_in_use = 0;
+
+       espchain = 0;
+       if(!SBus_chain) {
+#ifdef CONFIG_PCI
+               return 0;
+#else
+               panic("No SBUS in esp_detect()");
+#endif
+       }
+       for_each_sbus(sbus) {
+               for_each_sbusdev(sbdev_iter, sbus) {
+                       struct linux_sbus_device *espdma = 0;
+                       int hme = 0;
+
+                       /* Is it an esp sbus device? */
+                       esp_dev = sbdev_iter;
+                       if(strcmp(esp_dev->prom_name, "esp") &&
+                          strcmp(esp_dev->prom_name, "SUNW,esp")) {
+                               if(!strcmp(esp_dev->prom_name, "SUNW,fas")) {
+                                       hme = 1;
+                                       espdma = esp_dev;
+                               } else {
+                                       if(!esp_dev->child ||
+                                          (strcmp(esp_dev->prom_name, "espdma") &&
+                                           strcmp(esp_dev->prom_name, "dma")))
+                                               continue; /* nope... */
+                                       espdma = esp_dev;
+                                       esp_dev = esp_dev->child;
+                                       if(strcmp(esp_dev->prom_name, "esp") &&
+                                          strcmp(esp_dev->prom_name, "SUNW,esp"))
+                                               continue; /* how can this happen? */
+                               }
+                       }
+                       
+                       if (detect_one_esp(tpnt, esp_dev, espdma, sbus, nesps++, hme) < 0)
+                               continue;
+                               
+                       esps_in_use++;
+               } /* for each sbusdev */
+       } /* for each sbus */
+       printk("ESP: Total of %d ESP hosts found, %d actually in use.\n", nesps,
+              esps_in_use);
+       esps_running = esps_in_use;
+       return esps_in_use;
+}
+
+#endif /* !CONFIG_SUN4 */
+
+/* The info function will return whatever useful
+ * information the developer sees fit.  If not provided, then
+ * the name field will be used instead.
+ */
+const char *esp_info(struct Scsi_Host *host)
+{
+       struct Sparc_ESP *esp;
+
+       esp = (struct Sparc_ESP *) host->hostdata;
+       switch(esp->erev) {
+       case esp100:
+               return "Sparc ESP100 (NCR53C90)";
+       case esp100a:
+               return "Sparc ESP100A (NCR53C90A)";
+       case esp236:
+               return "Sparc ESP236";
+       case fas236:
+               return "Sparc ESP236-FAST";
+       case fashme:
+               return "Sparc ESP366-HME";
+       case fas100a:
+               return "Sparc ESP100A-FAST";
+       default:
+               panic("Bogon ESP revision");
+       };
+}
+
+/* From Wolfgang Stanglmeier's NCR scsi driver. */
+struct info_str
+{
+       char *buffer;
+       int length;
+       int offset;
+       int pos;
+};
+
+static void copy_mem_info(struct info_str *info, char *data, int len)
+{
+       if (info->pos + len > info->length)
+               len = info->length - info->pos;
+
+       if (info->pos + len < info->offset) {
+               info->pos += len;
+               return;
+       }
+       if (info->pos < info->offset) {
+               data += (info->offset - info->pos);
+               len  -= (info->offset - info->pos);
+       }
+
+       if (len > 0) {
+               memcpy(info->buffer + info->pos, data, len);
+               info->pos += len;
+       }
+}
+
+static int copy_info(struct info_str *info, char *fmt, ...)
+{
+       va_list args;
+       char buf[81];
+       int len;
+
+       va_start(args, fmt);
+       len = vsprintf(buf, fmt, args);
+       va_end(args);
+
+       copy_mem_info(info, buf, len);
+       return len;
+}
+
+static int esp_host_info(struct Sparc_ESP *esp, char *ptr, off_t offset, int len)
+{
+       struct info_str info;
+       int i;
+
+       info.buffer     = ptr;
+       info.length     = len;
+       info.offset     = offset;
+       info.pos        = 0;
+
+       copy_info(&info, "Sparc ESP Host Adapter:\n");
+       copy_info(&info, "\tPROM node\t\t%08lx\n", (unsigned long) esp->prom_node);
+       copy_info(&info, "\tPROM name\t\t%s\n", esp->prom_name);
+       copy_info(&info, "\tESP Model\t\t");
+       switch(esp->erev) {
+       case esp100:
+               copy_info(&info, "ESP100\n");
+               break;
+       case esp100a:
+               copy_info(&info, "ESP100A\n");
+               break;
+       case esp236:
+               copy_info(&info, "ESP236\n");
+               break;
+       case fas236:
+               copy_info(&info, "FAS236\n");
+               break;
+       case fas100a:
+               copy_info(&info, "FAS100A\n");
+               break;
+       case fast:
+               copy_info(&info, "FAST\n");
+               break;
+       case fashme:
+               copy_info(&info, "Happy Meal FAS\n");
+               break;
+       case espunknown:
+       default:
+               copy_info(&info, "Unknown!\n");
+               break;
+       };
+       copy_info(&info, "\tDMA Revision\t\t");
+       switch(esp->dma->revision) {
+       case dvmarev0:
+               copy_info(&info, "Rev 0\n");
+               break;
+       case dvmaesc1:
+               copy_info(&info, "ESC Rev 1\n");
+               break;
+       case dvmarev1:
+               copy_info(&info, "Rev 1\n");
+               break;
+       case dvmarev2:
+               copy_info(&info, "Rev 2\n");
+               break;
+       case dvmarev3:
+               copy_info(&info, "Rev 3\n");
+               break;
+       case dvmarevplus:
+               copy_info(&info, "Rev 1+\n");
+               break;
+       case dvmahme:
+               copy_info(&info, "Rev HME/FAS\n");
+               break;
+       default:
+               copy_info(&info, "Unknown!\n");
+               break;
+       };
+       copy_info(&info, "\tLive Targets\t\t[ ");
+       for(i = 0; i < 15; i++) {
+               if(esp->targets_present & (1 << i))
+                       copy_info(&info, "%d ", i);
+       }
+       copy_info(&info, "]\n\n");
+       
+       /* Now describe the state of each existing target. */
+       copy_info(&info, "Target #\tconfig3\t\tSync Capabilities\tDisconnect\tWide\n");
+       for(i = 0; i < 15; i++) {
+               if(esp->targets_present & (1 << i)) {
+                       Scsi_Device *SDptr = esp->ehost->host_queue;
+
+                       while((SDptr->host != esp->ehost) &&
+                             (SDptr->id != i) &&
+                             (SDptr->next))
+                               SDptr = SDptr->next;
+
+                       copy_info(&info, "%d\t\t", i);
+                       copy_info(&info, "%08lx\t", esp->config3[i]);
+                       copy_info(&info, "[%02lx,%02lx]\t\t\t", SDptr->sync_max_offset,
+                                 SDptr->sync_min_period);
+                       copy_info(&info, "%s\t\t", SDptr->disconnect ? "yes" : "no");
+                       copy_info(&info, "%s\n",
+                                 (esp->config3[i] & ESP_CONFIG3_EWIDE) ? "yes" : "no");
+               }
+       }
+
+       return info.pos > info.offset? info.pos - info.offset : 0;
+}
+
+/* ESP proc filesystem code. */
+int esp_proc_info(char *buffer, char **start, off_t offset, int length,
+                 int hostno, int inout)
+{
+       struct Sparc_ESP *esp;
+
+       if(inout)
+               return -EINVAL; /* not yet */
+
+       for_each_esp(esp) {
+               if(esp->ehost->host_no == hostno)
+                       break;
+       }
+       if(!esp)
+               return -EINVAL;
+
+       if(start)
+               *start = buffer;
+
+       return esp_host_info(esp, buffer, offset, length);
+}
+
+static void esp_get_dmabufs(struct Sparc_ESP *esp, Scsi_Cmnd *sp)
+{
+       if(sp->use_sg == 0) {
+               sp->SCp.this_residual = sp->request_bufflen;
+               sp->SCp.buffer = (struct scatterlist *) sp->request_buffer;
+               sp->SCp.buffers_residual = 0;
+               sp->SCp.have_data_in = mmu_get_scsi_one((char *)sp->SCp.buffer,
+                                                       sp->SCp.this_residual,
+                                                       esp->edev->my_bus);
+               sp->SCp.ptr = (char *) ((unsigned long)sp->SCp.have_data_in);
+       } else {
+               sp->SCp.buffer = (struct scatterlist *) sp->buffer;
+               sp->SCp.buffers_residual = sp->use_sg - 1;
+               sp->SCp.this_residual = sp->SCp.buffer->length;
+               mmu_get_scsi_sgl((struct mmu_sglist *) sp->SCp.buffer,
+                                sp->SCp.buffers_residual,
+                                esp->edev->my_bus);
+               sp->SCp.ptr = (char *) ((unsigned long)sp->SCp.buffer->dvma_address);
+       }
+}
+
+static void esp_release_dmabufs(struct Sparc_ESP *esp, Scsi_Cmnd *sp)
+{
+       if(sp->use_sg == 0)
+               mmu_release_scsi_one(sp->SCp.have_data_in,
+                                    sp->request_bufflen,
+                                    esp->edev->my_bus);
+       else
+               mmu_release_scsi_sgl((struct mmu_sglist *)
+                                    sp->buffer, sp->use_sg - 1,
+                                    esp->edev->my_bus);
+}
+
+static void esp_restore_pointers(struct Sparc_ESP *esp, Scsi_Cmnd *sp)
+{
+       struct esp_pointers *ep = &esp->data_pointers[sp->target];
+
+       sp->SCp.ptr = ep->saved_ptr;
+       sp->SCp.buffer = ep->saved_buffer;
+       sp->SCp.this_residual = ep->saved_this_residual;
+       sp->SCp.buffers_residual = ep->saved_buffers_residual;
+}
+
+static void esp_save_pointers(struct Sparc_ESP *esp, Scsi_Cmnd *sp)
+{
+       struct esp_pointers *ep = &esp->data_pointers[sp->target];
+
+       ep->saved_ptr = sp->SCp.ptr;
+       ep->saved_buffer = sp->SCp.buffer;
+       ep->saved_this_residual = sp->SCp.this_residual;
+       ep->saved_buffers_residual = sp->SCp.buffers_residual;
+}
+
+/* Some rules:
+ *
+ *   1) Never ever panic while something is live on the bus.
+ *      If there is to be any chance of syncing the disks this
+ *      rule is to be obeyed.
+ *
+ *   2) Any target that causes a foul condition will no longer
+ *      have synchronous transfers done to it, no questions
+ *      asked.
+ *
+ *   3) Keep register accesses to a minimum.  Think about some
+ *      day when we have Xbus machines this is running on and
+ *      the ESP chip is on the other end of the machine on a
+ *      different board from the cpu where this is running.
+ */
+
+/* Fire off a command.  We assume the bus is free and that the only
+ * case where we could see an interrupt is where we have disconnected
+ * commands active and they are trying to reselect us.
+ */
+static inline void esp_check_cmd(struct Sparc_ESP *esp, Scsi_Cmnd *sp)
+{
+       switch(sp->cmd_len) {
+       case 6:
+       case 10:
+       case 12:
+               esp->esp_slowcmd = 0;
+               break;
+
+       default:
+               esp->esp_slowcmd = 1;
+               esp->esp_scmdleft = sp->cmd_len;
+               esp->esp_scmdp = &sp->cmnd[0];
+               break;
+       };
+}
+
+static inline void build_sync_nego_msg(struct Sparc_ESP *esp, int period, int offset)
+{
+       esp->cur_msgout[0] = EXTENDED_MESSAGE;
+       esp->cur_msgout[1] = 3;
+       esp->cur_msgout[2] = EXTENDED_SDTR;
+       esp->cur_msgout[3] = period;
+       esp->cur_msgout[4] = offset;
+       esp->msgout_len = 5;
+}
+
+/* SIZE is in bits, currently HME only supports 16 bit wide transfers. */
+static inline void build_wide_nego_msg(struct Sparc_ESP *esp, int size)
+{
+       esp->cur_msgout[0] = EXTENDED_MESSAGE;
+       esp->cur_msgout[1] = 2;
+       esp->cur_msgout[2] = EXTENDED_WDTR;
+       switch(size) {
+       case 32:
+               esp->cur_msgout[3] = 2;
+               break;
+       case 16:
+               esp->cur_msgout[3] = 1;
+               break;
+       case 8:
+       default:
+               esp->cur_msgout[3] = 0;
+               break;
+       };
+
+       esp->msgout_len = 4;
+}
+
+static void esp_exec_cmd(struct Sparc_ESP *esp)
+{
+       struct sparc_dma_registers *dregs = esp->dregs;
+       struct Sparc_ESP_regs *eregs = esp->eregs;
+       Scsi_Cmnd *SCptr;
+       Scsi_Device *SDptr;
+       volatile unchar *cmdp = esp->esp_command;
+       unsigned char the_esp_command;
+       int lun, target;
+       int i;
+
+       /* Hold off if we have disconnected commands and
+        * an IRQ is showing...
+        */
+       if(esp->disconnected_SC && DMA_IRQ_P(dregs))
+               return;
+
+       /* Grab first member of the issue queue. */
+       SCptr = esp->current_SC = remove_first_SC(&esp->issue_SC);
+
+       /* Safe to panic here because current_SC is null. */
+       if(!SCptr)
+               panic("esp: esp_exec_cmd and issue queue is NULL");
+
+       SDptr = SCptr->device;
+       lun = SCptr->lun;
+       target = SCptr->target;
+
+       esp->snip = 0;
+       esp->msgout_len = 0;
+
+       /* Send it out whole, or piece by piece?   The ESP
+        * only knows how to automatically send out 6, 10,
+        * and 12 byte commands.  I used to think that the
+        * Linux SCSI code would never throw anything other
+        * than that to us, but then again there is the
+        * SCSI generic driver which can send us anything.
+        */
+       esp_check_cmd(esp, SCptr);
+
+       /* If arbitration/selection is successful, the ESP will leave
+        * ATN asserted, causing the target to go into message out
+        * phase.  The ESP will feed the target the identify and then
+        * the target can only legally go to one of command,
+        * datain/out, status, or message in phase, or stay in message
+        * out phase (should we be trying to send a sync negotiation
+        * message after the identify).  It is not allowed to drop
+        * BSY, but some buggy targets do and we check for this
+        * condition in the selection complete code.  Most of the time
+        * we'll make the command bytes available to the ESP and it
+        * will not interrupt us until it finishes command phase, we
+        * cannot do this for command sizes the ESP does not
+        * understand and in this case we'll get interrupted right
+        * when the target goes into command phase.
+        *
+        * It is absolutely _illegal_ in the presence of SCSI-2 devices
+        * to use the ESP select w/o ATN command.  When SCSI-2 devices are
+        * present on the bus we _must_ always go straight to message out
+        * phase with an identify message for the target.  Being that
+        * selection attempts in SCSI-1 w/o ATN was an option, doing SCSI-2
+        * selections should not confuse SCSI-1 we hope.
+        */
+
+       if(SDptr->sync) {
+               /* this targets sync is known */
+do_sync_known:
+               if(SDptr->disconnect)
+                       *cmdp++ = IDENTIFY(1, lun);
+               else
+                       *cmdp++ = IDENTIFY(0, lun);
+
+               if(esp->esp_slowcmd) {
+                       the_esp_command = (ESP_CMD_SELAS | ESP_CMD_DMA);
+                       esp_advance_phase(SCptr, in_slct_stop);
+               } else {
+                       the_esp_command = (ESP_CMD_SELA | ESP_CMD_DMA);
+                       esp_advance_phase(SCptr, in_slct_norm);
+               }
+       } else if(!(esp->targets_present & (1<<target)) || !(SDptr->disconnect)) {
+               /* After the bootup SCSI code sends both the
+                * TEST_UNIT_READY and INQUIRY commands we want
+                * to at least attempt allowing the device to
+                * disconnect.
+                */
+               ESPMISC(("esp: Selecting device for first time. target=%d "
+                        "lun=%d\n", target, SCptr->lun));
+               if(!SDptr->borken && !SDptr->disconnect)
+                       SDptr->disconnect = 1;
+
+               *cmdp++ = IDENTIFY(0, lun);
+               esp->prevmsgout = NOP;
+               esp_advance_phase(SCptr, in_slct_norm);
+               the_esp_command = (ESP_CMD_SELA | ESP_CMD_DMA);
+
+               /* Take no chances... */
+               SDptr->sync_max_offset = 0;
+               SDptr->sync_min_period = 0;
+       } else {
+               /* Sorry, I have had way too many problems with
+                * various CDROM devices on ESP. -DaveM
+                */
+               int cdrom_hwbug_wkaround = 0;
+
+               /* Never allow disconnects or synchronous transfers on
+                * SparcStation1 and SparcStation1+.  Allowing those
+                * to be enabled seems to lockup the machine completely.
+                */
+               if((idprom->id_machtype == (SM_SUN4C | SM_4C_SS1)) ||
+                  (idprom->id_machtype == (SM_SUN4C | SM_4C_SS1PLUS))) {
+                       /* But we are nice and allow tapes to disconnect. */
+                       if(SDptr->type == TYPE_TAPE)
+                               SDptr->disconnect = 1;
+                       else
+                               SDptr->disconnect = 0;
+                       SDptr->sync_max_offset = 0;
+                       SDptr->sync_min_period = 0;
+                       SDptr->sync = 1;
+                       esp->snip = 0;
+                       goto do_sync_known;
+               }
+
+               /* We've talked to this guy before,
+                * but never negotiated.  Let's try,
+                * need to attempt WIDE first, before
+                * sync nego, as per SCSI 2 standard.
+                */
+               if(esp->erev == fashme && !SDptr->wide) {
+                       if(!SDptr->borken &&
+                          SDptr->type != TYPE_ROM) {
+                               build_wide_nego_msg(esp, 16);
+                               SDptr->wide = 1;
+                               esp->wnip = 1;
+                               goto after_nego_msg_built;
+                       } else {
+                               SDptr->wide = 1;
+                               /* Fall through and try sync. */
+                       }
+               }
+
+               if(!SDptr->borken) {
+                       if((SDptr->type == TYPE_ROM)) {
+                               /* Nice try sucker... */
+                               ESPMISC(("esp%d: Disabling sync for buggy "
+                                        "CDROM.\n", esp->esp_id));
+                               cdrom_hwbug_wkaround = 1;
+                               build_sync_nego_msg(esp, 0, 0);
+                       } else {
+                               build_sync_nego_msg(esp, esp->sync_defp, 15);
+                       }
+               } else {
+                       build_sync_nego_msg(esp, 0, 0);
+               }
+               SDptr->sync = 1;
+               esp->snip = 1;
+
+after_nego_msg_built:
+               /* A fix for broken SCSI1 targets, when they disconnect
+                * they lock up the bus and confuse ESP.  So disallow
+                * disconnects for SCSI1 targets for now until we
+                * find a better fix.
+                *
+                * Addendum: This is funny, I figured out what was going
+                *           on.  The blotzed SCSI1 target would disconnect,
+                *           one of the other SCSI2 targets or both would be
+                *           disconnected as well.  The SCSI1 target would
+                *           stay disconnected long enough that we start
+                *           up a command on one of the SCSI2 targets.  As
+                *           the ESP is arbitrating for the bus the SCSI1
+                *           target begins to arbitrate as well to reselect
+                *           the ESP.  The SCSI1 target refuses to drop it's
+                *           ID bit on the data bus even though the ESP is
+                *           at ID 7 and is the obvious winner for any
+                *           arbitration.  The ESP is a poor sport and refuses
+                *           to lose arbitration, it will continue indefinately
+                *           trying to arbitrate for the bus and can only be
+                *           stopped via a chip reset or SCSI bus reset.
+                *           Therefore _no_ disconnects for SCSI1 targets
+                *           thank you very much. ;-)
+                */
+               if(((SDptr->scsi_level < 3) && (SDptr->type != TYPE_TAPE)) ||
+                  cdrom_hwbug_wkaround || SDptr->borken) {
+                       ESPMISC((KERN_INFO "esp%d: Disabling DISCONNECT for target %d "
+                                "lun %d\n", esp->esp_id, SCptr->target, SCptr->lun));
+                       SDptr->disconnect = 0;
+                       *cmdp++ = IDENTIFY(0, lun);
+               } else {
+                       *cmdp++ = IDENTIFY(1, lun);
+               }
+
+               /* ESP fifo is only so big...
+                * Make this look like a slow command.
+                */
+               esp->esp_slowcmd = 1;
+               esp->esp_scmdleft = SCptr->cmd_len;
+               esp->esp_scmdp = &SCptr->cmnd[0];
+
+               the_esp_command = (ESP_CMD_SELAS | ESP_CMD_DMA);
+               esp_advance_phase(SCptr, in_slct_msg);
+       }
+
+       if(!esp->esp_slowcmd)
+               for(i = 0; i < SCptr->cmd_len; i++)
+                       *cmdp++ = SCptr->cmnd[i];
+
+       /* HME sucks... */
+       if(esp->erev == fashme)
+               eregs->esp_busid = (target & 0xf) |
+                       (ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT);
+       else
+               eregs->esp_busid = (target & 7);
+       if (esp->prev_soff != SDptr->sync_max_offset ||
+           esp->prev_stp  != SDptr->sync_min_period ||
+           (esp->erev > esp100a &&
+            esp->prev_cfg3 != esp->config3[target])) {
+               eregs->esp_soff = esp->prev_soff = SDptr->sync_max_offset;
+               eregs->esp_stp  = esp->prev_stp  = SDptr->sync_min_period;
+               if(esp->erev > esp100a)
+                       eregs->esp_cfg3 =
+                               esp->prev_cfg3 =
+                               esp->config3[target];
+       }
+       i = (cmdp - esp->esp_command);
+
+       if(esp->erev == fashme) {
+               esp_cmd(esp, eregs, ESP_CMD_FLUSH); /* Grrr! */
+
+               /* Set up the DMA and HME counters */
+               eregs->esp_tclow = i;
+               eregs->esp_tcmed = 0;
+               eregs->fas_rlo = 0;
+               eregs->fas_rhi = 0;
+               esp_cmd(esp, eregs, the_esp_command);
+
+               /* Talk about touchy hardware... */
+               esp->prev_hme_dmacsr = ((esp->prev_hme_dmacsr |
+                                        (DMA_SCSI_DISAB | DMA_ENABLE)) &
+                                       ~(DMA_ST_WRITE));
+               dregs->cnt = 16;
+               dregs->st_addr = esp->esp_command_dvma;
+               dregs->cond_reg = esp->prev_hme_dmacsr;
+       } else {
+               /* Set up the DMA and ESP counters */
+               eregs->esp_tclow = i;
+               eregs->esp_tcmed = 0;
+               dregs->cond_reg = ((dregs->cond_reg & ~(DMA_ST_WRITE)) | DMA_ENABLE);
+               if(esp->dma->revision == dvmaesc1) {
+                       if(i) /* Workaround ESC gate array SBUS rerun bug. */
+                               dregs->cnt = (PAGE_SIZE);
+               }
+               dregs->st_addr = esp->esp_command_dvma;
+
+               /* Tell ESP to "go". */
+               esp_cmd(esp, eregs, the_esp_command);
+       }
+}
+
+/* Queue a SCSI command delivered from the mid-level Linux SCSI code. */
+int esp_queue(Scsi_Cmnd *SCpnt, void (*done)(Scsi_Cmnd *))
+{
+       struct Sparc_ESP *esp;
+       struct sparc_dma_registers *dregs;
+
+       /* Set up func ptr and initial driver cmd-phase. */
+       SCpnt->scsi_done = done;
+       SCpnt->SCp.phase = not_issued;
+
+       esp = (struct Sparc_ESP *) SCpnt->host->hostdata;
+       dregs = esp->dregs;
+
+       /* We use the scratch area. */
+       ESPQUEUE(("esp_queue: target=%d lun=%d ", SCpnt->target, SCpnt->lun));
+       ESPDISC(("N<%02x,%02x>", SCpnt->target, SCpnt->lun));
+
+       esp_get_dmabufs(esp, SCpnt);
+       esp_save_pointers(esp, SCpnt); /* FIXME for tag queueing */
+
+       SCpnt->SCp.Status           = CHECK_CONDITION;
+       SCpnt->SCp.Message          = 0xff;
+       SCpnt->SCp.sent_command     = 0;
+
+       /* Place into our queue. */
+       if(SCpnt->cmnd[0] == REQUEST_SENSE) {
+               ESPQUEUE(("RQSENSE\n"));
+               prepend_SC(&esp->issue_SC, SCpnt);
+       } else {
+               ESPQUEUE(("\n"));
+               append_SC(&esp->issue_SC, SCpnt);
+       }
+
+       /* Run it now if we can. */
+       if(!esp->current_SC && !esp->resetting_bus)
+               esp_exec_cmd(esp);
+
+       return 0;
+}
+
+/* Only queuing supported in this ESP driver. */
+int esp_command(Scsi_Cmnd *SCpnt)
+{
+       struct Sparc_ESP *esp = (struct Sparc_ESP *) SCpnt->host->hostdata;
+
+       ESPLOG(("esp%d: esp_command() called...\n", esp->esp_id));
+       return -1;
+}
+
+/* Dump driver state. */
+static void esp_dump_cmd(Scsi_Cmnd *SCptr)
+{
+       ESPLOG(("[tgt<%02x> lun<%02x> "
+               "pphase<%s> cphase<%s>]",
+               SCptr->target, SCptr->lun,
+               phase_string(SCptr->SCp.sent_command),
+               phase_string(SCptr->SCp.phase)));
+}
+
+static void esp_dump_state(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                          struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+#ifdef DEBUG_ESP_CMDS
+       int i;
+#endif
+
+       ESPLOG(("esp%d: dumping state\n", esp->esp_id));
+       ESPLOG(("esp%d: dma -- cond_reg<%08x> addr<%08x>\n",
+               esp->esp_id, dregs->cond_reg, dregs->st_addr));
+       ESPLOG(("esp%d: SW [sreg<%02x> sstep<%02x> ireg<%02x>]\n",
+               esp->esp_id, esp->sreg, esp->seqreg, esp->ireg));
+       ESPLOG(("esp%d: HW reread [sreg<%02x> sstep<%02x> ireg<%02x>]\n",
+               esp->esp_id, eregs->esp_status, eregs->esp_sstep, eregs->esp_intrpt));
+#ifdef DEBUG_ESP_CMDS
+       printk("esp%d: last ESP cmds [", esp->esp_id);
+       i = (esp->espcmdent - 1) & 31;
+       printk("<");
+       esp_print_cmd(esp->espcmdlog[i]);
+       printk(">");
+       i = (i - 1) & 31;
+       printk("<");
+       esp_print_cmd(esp->espcmdlog[i]);
+       printk(">");
+       i = (i - 1) & 31;
+       printk("<");
+       esp_print_cmd(esp->espcmdlog[i]);
+       printk(">");
+       i = (i - 1) & 31;
+       printk("<");
+       esp_print_cmd(esp->espcmdlog[i]);
+       printk(">");
+       printk("]\n");
+#endif /* (DEBUG_ESP_CMDS) */
+
+       if(SCptr) {
+               ESPLOG(("esp%d: current command ", esp->esp_id));
+               esp_dump_cmd(SCptr);
+       }
+       ESPLOG(("\n"));
+       SCptr = esp->disconnected_SC;
+       ESPLOG(("esp%d: disconnected ", esp->esp_id));
+       while(SCptr) {
+               esp_dump_cmd(SCptr);
+               SCptr = (Scsi_Cmnd *) SCptr->host_scribble;
+       }
+       ESPLOG(("\n"));
+}
+
+/* Abort a command. */
+int esp_abort(Scsi_Cmnd *SCptr)
+{
+       struct Sparc_ESP *esp = (struct Sparc_ESP *) SCptr->host->hostdata;
+       struct Sparc_ESP_regs *eregs = esp->eregs;
+       struct sparc_dma_registers *dregs = esp->dregs;
+       int don;
+
+       ESPLOG(("esp%d: Aborting command\n", esp->esp_id));
+       esp_dump_state(esp, eregs, dregs);
+
+       /* Wheee, if this is the current command on the bus, the
+        * best we can do is assert ATN and wait for msgout phase.
+        * This should even fix a hung SCSI bus when we lose state
+        * in the driver and timeout because the eventual phase change
+        * will cause the ESP to (eventually) give an interrupt.
+        */
+       if(esp->current_SC == SCptr) {
+               esp->cur_msgout[0] = ABORT;
+               esp->msgout_len = 1;
+               esp->msgout_ctr = 0;
+               esp_cmd(esp, eregs, ESP_CMD_SATN);
+               return SCSI_ABORT_PENDING;
+       }
+
+       /* If it is still in the issue queue then we can safely
+        * call the completion routine and report abort success.
+        */
+       don = (dregs->cond_reg & DMA_INT_ENAB);
+       if(don) {
+               DMA_INTSOFF(dregs);
+               synchronize_irq();
+       }
+       if(esp->issue_SC) {
+               Scsi_Cmnd **prev, *this;
+               for(prev = (&esp->issue_SC), this = esp->issue_SC;
+                   this;
+                   prev = (Scsi_Cmnd **) &(this->host_scribble),
+                   this = (Scsi_Cmnd *) this->host_scribble) {
+                       if(this == SCptr) {
+                               *prev = (Scsi_Cmnd *) this->host_scribble;
+                               this->host_scribble = NULL;
+                               esp_release_dmabufs(esp, this);
+                               this->result = DID_ABORT << 16;
+                               this->done(this);
+                               if(don)
+                                       DMA_INTSON(dregs);
+                               return SCSI_ABORT_SUCCESS;
+                       }
+               }
+       }
+
+       /* Yuck, the command to abort is disconnected, it is not
+        * worth trying to abort it now if something else is live
+        * on the bus at this time.  So, we let the SCSI code wait
+        * a little bit and try again later.
+        */
+       if(esp->current_SC) {
+               if(don)
+                       DMA_INTSON(dregs);
+               return SCSI_ABORT_BUSY;
+       }
+
+       /* It's disconnected, we have to reconnect to re-establish
+        * the nexus and tell the device to abort.  However, we really
+        * cannot 'reconnect' per se, therefore we tell the upper layer
+        * the safest thing we can.  This is, wait a bit, if nothing
+        * happens, we are really hung so reset the bus.
+        */
+
+       if(don)
+               DMA_INTSON(dregs);
+       return SCSI_ABORT_SNOOZE;
+}
+
+/* We've sent ESP_CMD_RS to the ESP, the interrupt had just
+ * arrived indicating the end of the SCSI bus reset.  Our job
+ * is to clean out the command queues and begin re-execution
+ * of SCSI commands once more.
+ */
+static int esp_finish_reset(struct Sparc_ESP *esp,
+                           struct Sparc_ESP_regs *eregs,
+                           struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *sp = esp->current_SC;
+
+       /* Clean up currently executing command, if any. */
+       if (sp != NULL) {
+               esp_release_dmabufs(esp, sp);
+               sp->result = (DID_RESET << 16);
+               sp->scsi_done(sp);
+               esp->current_SC = NULL;
+       }
+
+       /* Clean up disconnected queue, they have been invalidated
+        * by the bus reset.
+        */
+       if (esp->disconnected_SC) {
+               while((sp = remove_first_SC(&esp->disconnected_SC)) != NULL) {
+                       esp_release_dmabufs(esp, sp);
+                       sp->result = (DID_RESET << 16);
+                       sp->scsi_done(sp);
+               }
+       }
+
+       /* SCSI bus reset is complete. */
+       esp->resetting_bus = 0;
+
+       /* Ok, now it is safe to get commands going once more. */
+       if(esp->issue_SC)
+               esp_exec_cmd(esp);
+
+       return do_intr_end;
+}
+
+static int esp_do_resetbus(struct Sparc_ESP *esp,
+                          struct Sparc_ESP_regs *eregs,
+                          struct sparc_dma_registers *dregs)
+{
+       ESPLOG(("esp%d: Resetting scsi bus\n", esp->esp_id));
+       esp->resetting_bus = 1;
+       esp_cmd(esp, eregs, ESP_CMD_RS);
+
+       return do_intr_end;
+}
+
+/* Reset ESP chip, reset hanging bus, then kill active and
+ * disconnected commands for targets without soft reset.
+ */
+int esp_reset(Scsi_Cmnd *SCptr, unsigned int how)
+{
+       struct Sparc_ESP *esp = (struct Sparc_ESP *) SCptr->host->hostdata;
+
+       (void) esp_do_resetbus(esp, esp->eregs, esp->dregs);
+       return SCSI_RESET_PENDING;
+}
+
+/* Internal ESP done function. */
+static void esp_done(struct Sparc_ESP *esp, int error)
+{
+       Scsi_Cmnd *done_SC;
+
+       if(esp->current_SC) {
+               done_SC = esp->current_SC;
+               esp->current_SC = NULL;
+               esp_release_dmabufs(esp, done_SC);
+               done_SC->result = error;
+               done_SC->scsi_done(done_SC);
+
+               /* Bus is free, issue any commands in the queue. */
+               if(esp->issue_SC && !esp->current_SC)
+                       esp_exec_cmd(esp);
+       } else {
+               /* Panic is safe as current_SC is null so we may still
+                * be able to accept more commands to sync disk buffers.
+                */
+               ESPLOG(("panicing\n"));
+               panic("esp: done() called with NULL esp->current_SC");
+       }
+}
+
+/* Wheee, ESP interrupt engine. */  
+
+/* Forward declarations. */
+static int esp_do_phase_determine(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                                 struct sparc_dma_registers *dregs);
+static int esp_do_data_finale(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                             struct sparc_dma_registers *dregs);
+static int esp_select_complete(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                              struct sparc_dma_registers *dregs);
+static int esp_do_status(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                        struct sparc_dma_registers *dregs);
+static int esp_do_msgin(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                       struct sparc_dma_registers *dregs);
+static int esp_do_msgindone(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                           struct sparc_dma_registers *dregs);
+static int esp_do_msgout(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                        struct sparc_dma_registers *dregs);
+static int esp_do_cmdbegin(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                          struct sparc_dma_registers *dregs);
+
+#define sreg_datainp(__sreg)  (((__sreg) & ESP_STAT_PMASK) == ESP_DIP)
+#define sreg_dataoutp(__sreg) (((__sreg) & ESP_STAT_PMASK) == ESP_DOP)
+
+/* Read any bytes found in the FAS366 fifo, storing them into
+ * the ESP driver software state structure.
+ */
+static void hme_fifo_read(struct Sparc_ESP *esp,
+                         struct Sparc_ESP_regs *eregs)
+{
+       unsigned long count = 0;
+       unchar status = esp->sreg;
+
+       /* Cannot safely frob the fifo for these following cases, but
+        * we must always read the fifo when the reselect interrupt
+        * is pending.
+        */
+       if(((esp->ireg & ESP_INTR_RSEL) == 0)   &&
+          (sreg_datainp(status)                ||
+           sreg_dataoutp(status)               ||
+           (esp->current_SC &&
+            esp->current_SC->SCp.phase == in_data_done))) {
+               ESPHME(("<wkaround_skipped>"));
+       } else {
+               unsigned long fcnt = eregs->esp_fflags & ESP_FF_FBYTES;
+
+               /* The HME stores bytes in multiples of 2 in the fifo. */
+               ESPHME(("hme_fifo[fcnt=%d", (int)fcnt));
+               while(fcnt) {
+                       esp->hme_fifo_workaround_buffer[count++] = eregs->esp_fdata;
+                       esp->hme_fifo_workaround_buffer[count++] = eregs->esp_fdata;
+                       ESPHME(("<%02x,%02x>", esp->hme_fifo_workaround_buffer[count-2], esp->hme_fifo_workaround_buffer[count-1]));
+                       fcnt--;
+               }
+               if(eregs->esp_status2 & ESP_STAT2_F1BYTE) {
+                       ESPHME(("<poke_byte>"));
+                       eregs->esp_fdata = 0;
+                       esp->hme_fifo_workaround_buffer[count++] = eregs->esp_fdata;
+                       ESPHME(("<%02x,0x00>", esp->hme_fifo_workaround_buffer[count-1]));
+                       ESPHME(("CMD_FLUSH"));
+                       esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+               } else {
+                       ESPHME(("no_xtra_byte"));
+               }
+       }
+       ESPHME(("wkarnd_cnt=%d]", (int)count));
+       esp->hme_fifo_workaround_count = count;
+}
+
+static inline void hme_fifo_push(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                                unchar *bytes, unchar count)
+{
+       esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+       while(count) {
+               eregs->esp_fdata = *bytes++;
+               eregs->esp_fdata = 0;
+               count--;
+       }
+}
+
+/* We try to avoid some interrupts by jumping ahead and see if the ESP
+ * has gotten far enough yet.  Hence the following.
+ */
+static inline int skipahead1(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                            struct sparc_dma_registers *dregs,
+                            Scsi_Cmnd *scp, int prev_phase, int new_phase)
+{
+       if(scp->SCp.sent_command != prev_phase)
+               return 0;
+       if(DMA_IRQ_P(dregs)) {
+               /* Yes, we are able to save an interrupt. */
+               if (esp->erev == fashme)
+                       esp->sreg2 = eregs->esp_status2;
+               esp->sreg = (eregs->esp_status & ~(ESP_STAT_INTR));
+               esp->ireg = eregs->esp_intrpt;
+               if(esp->erev == fashme) {
+                       /* This chip is really losing. */
+                       ESPHME(("HME["));
+                       /* Must latch fifo before reading the interrupt
+                        * register else garbage ends up in the FIFO
+                        * which confuses the driver utterly.
+                        * Happy Meal indeed....
+                        */
+                       ESPHME(("fifo_workaround]"));
+                       if(!(esp->sreg2 & ESP_STAT2_FEMPTY) ||
+                          (esp->sreg2 & ESP_STAT2_F1BYTE))
+                               hme_fifo_read(esp, eregs);
+               }
+               if(!(esp->ireg & ESP_INTR_SR))
+                       return 0;
+               else
+                       return do_reset_complete;
+       }
+       /* Ho hum, target is taking forever... */
+       scp->SCp.sent_command = new_phase; /* so we don't recurse... */
+       return do_intr_end;
+}
+
+static inline int skipahead2(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                            struct sparc_dma_registers *dregs,
+                            Scsi_Cmnd *scp, int prev_phase1, int prev_phase2,
+                            int new_phase)
+{
+       if(scp->SCp.sent_command != prev_phase1 &&
+          scp->SCp.sent_command != prev_phase2)
+               return 0;
+       if(DMA_IRQ_P(dregs)) {
+               /* Yes, we are able to save an interrupt. */
+               if (esp->erev == fashme)
+                       esp->sreg2 = eregs->esp_status2;
+               esp->sreg = (eregs->esp_status & ~(ESP_STAT_INTR));
+               esp->ireg = eregs->esp_intrpt;
+               if(esp->erev == fashme) {
+                       /* This chip is really losing. */
+                       ESPHME(("HME["));
+
+                       /* Must latch fifo before reading the interrupt
+                        * register else garbage ends up in the FIFO
+                        * which confuses the driver utterly.
+                        * Happy Meal indeed....
+                        */
+                       ESPHME(("fifo_workaround]"));
+                       if(!(esp->sreg2 & ESP_STAT2_FEMPTY) ||
+                          (esp->sreg2 & ESP_STAT2_F1BYTE))
+                               hme_fifo_read(esp, eregs);
+               }
+               if(!(esp->ireg & ESP_INTR_SR))
+                       return 0;
+               else
+                       return do_reset_complete;
+       }
+       /* Ho hum, target is taking forever... */
+       scp->SCp.sent_command = new_phase; /* so we don't recurse... */
+       return do_intr_end;
+}
+
+/* Now some dma helpers. */
+static inline void dma_setup(struct sparc_dma_registers *dregs, enum dvma_rev drev,
+                            __u32 addr, int count, int write)
+{
+       unsigned long nreg = dregs->cond_reg;
+       if(write)
+               nreg |= DMA_ST_WRITE;
+       else
+               nreg &= ~(DMA_ST_WRITE);
+       nreg |= DMA_ENABLE;
+       dregs->cond_reg = nreg;
+       if(drev == dvmaesc1) {
+               /* This ESC gate array sucks! */
+               __u32 src = addr;
+               __u32 dest = src + count;
+
+               if(dest & (PAGE_SIZE - 1))
+                       count = PAGE_ALIGN(count);
+               dregs->cnt = count;
+       }
+       dregs->st_addr = addr;
+}
+
+static inline void dma_drain(struct sparc_dma_registers *dregs, enum dvma_rev drev)
+{
+       if(drev == dvmahme)
+               return;
+       if(dregs->cond_reg & DMA_FIFO_ISDRAIN) {
+               switch(drev) {
+               default:
+                       dregs->cond_reg |= DMA_FIFO_STDRAIN;
+
+               case dvmarev3:
+               case dvmaesc1:
+                       while(dregs->cond_reg & DMA_FIFO_ISDRAIN)
+                               udelay(1);
+               };
+       }
+}
+
+static inline void dma_invalidate(struct Sparc_ESP *esp,
+                                 struct sparc_dma_registers *dregs,
+                                 enum dvma_rev drev)
+{
+       unsigned int tmp;
+
+       if(drev == dvmahme) {
+               dregs->cond_reg = DMA_RST_SCSI;
+
+               esp->prev_hme_dmacsr = ((esp->prev_hme_dmacsr |
+                                        (DMA_PARITY_OFF | DMA_2CLKS |
+                                         DMA_SCSI_DISAB | DMA_INT_ENAB)) &
+                                       ~(DMA_ST_WRITE | DMA_ENABLE));
+
+               dregs->cond_reg = 0;
+               dregs->cond_reg = esp->prev_hme_dmacsr;
+
+               /* This is necessary to avoid having the SCSI channel
+                * engine lock up on us.
+                */
+               dregs->st_addr = 0;
+       } else {
+               while(dregs->cond_reg & DMA_PEND_READ)
+                       udelay(1);
+
+               tmp = dregs->cond_reg;
+               tmp &= ~(DMA_ENABLE | DMA_ST_WRITE | DMA_BCNT_ENAB);
+               tmp |= DMA_FIFO_INV;
+               dregs->cond_reg = tmp;
+               dregs->cond_reg = (tmp & ~(DMA_FIFO_INV));
+       }
+}
+
+static inline void dma_flashclear(struct Sparc_ESP *esp,
+                                 struct sparc_dma_registers *dregs,
+                                 enum dvma_rev drev)
+{
+       dma_drain(dregs, drev);
+       dma_invalidate(esp, dregs, drev);
+}
+
+static inline int dma_can_transfer(Scsi_Cmnd *sp, enum dvma_rev drev)
+{
+       __u32 base, end, sz;
+
+       if(drev == dvmarev3) {
+               sz = sp->SCp.this_residual;
+               if(sz > 0x1000000)
+                       sz = 0x1000000;
+       } else {
+               base = ((__u32)((unsigned long)sp->SCp.ptr));
+               base &= (0x1000000 - 1);
+               end = (base + sp->SCp.this_residual);
+               if(end > 0x1000000)
+                       end = 0x1000000;
+               sz = (end - base);
+       }
+       return sz;
+}
+
+/* Misc. esp helper macros. */
+#define esp_setcount(__eregs, __cnt, __hme) \
+       (__eregs)->esp_tclow = ((__cnt) & 0xff); \
+       (__eregs)->esp_tcmed = (((__cnt) >> 8) & 0xff); \
+       if(__hme) { \
+               (__eregs)->fas_rlo = 0; \
+               (__eregs)->fas_rhi = 0; \
+       }
+
+#define esp_getcount(__eregs) \
+       ((((__eregs)->esp_tclow)&0xff) | \
+        ((((__eregs)->esp_tcmed)&0xff) << 8))
+
+#define fcount(__esp, __eregs) \
+       (((__esp)->erev == fashme) ? \
+         (__esp)->hme_fifo_workaround_count : \
+         (__eregs)->esp_fflags & ESP_FF_FBYTES)
+
+#define fnzero(__esp, __eregs) \
+       (((__esp)->erev == fashme) ? 0 : \
+        (__eregs)->esp_fflags & ESP_FF_ONOTZERO)
+
+/* XXX speculative nops unnecessary when continuing amidst a data phase
+ * XXX even on esp100!!!  another case of flooding the bus with I/O reg
+ * XXX writes...
+ */
+#define esp_maybe_nop(__esp, __eregs) \
+       if((__esp)->erev == esp100) \
+               esp_cmd((__esp), (__eregs), ESP_CMD_NULL)
+
+#define sreg_to_dataphase(__sreg) \
+       ((((__sreg) & ESP_STAT_PMASK) == ESP_DOP) ? in_dataout : in_datain)
+
+/* The ESP100 when in synchronous data phase, can mistake a long final
+ * REQ pulse from the target as an extra byte, it places whatever is on
+ * the data lines into the fifo.  For now, we will assume when this
+ * happens that the target is a bit quirky and we don't want to
+ * be talking synchronously to it anyways.  Regardless, we need to
+ * tell the ESP to eat the extraneous byte so that we can proceed
+ * to the next phase.
+ */
+static inline int esp100_sync_hwbug(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                                   Scsi_Cmnd *sp, int fifocnt)
+{
+       /* Do not touch this piece of code. */
+       if((!(esp->erev == esp100)) ||
+          (!(sreg_datainp((esp->sreg = eregs->esp_status)) && !fifocnt) &&
+           !(sreg_dataoutp(esp->sreg) && !fnzero(esp, eregs)))) {
+               if(sp->SCp.phase == in_dataout)
+                       esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+               return 0;
+       } else {
+               /* Async mode for this guy. */
+               build_sync_nego_msg(esp, 0, 0);
+
+               /* Ack the bogus byte, but set ATN first. */
+               esp_cmd(esp, eregs, ESP_CMD_SATN);
+               esp_cmd(esp, eregs, ESP_CMD_MOK);
+               return 1;
+       }
+}
+
+/* This closes the window during a selection with a reselect pending, because
+ * we use DMA for the selection process the FIFO should hold the correct
+ * contents if we get reselected during this process.  So we just need to
+ * ack the possible illegal cmd interrupt pending on the esp100.
+ */
+static inline int esp100_reconnect_hwbug(struct Sparc_ESP *esp,
+                                        struct Sparc_ESP_regs *eregs)
+{
+       volatile unchar junk;
+
+       if(esp->erev != esp100)
+               return 0;
+       junk = eregs->esp_intrpt;
+       if(junk & ESP_INTR_SR)
+               return 1;
+       return 0;
+}
+
+/* This verifies the BUSID bits during a reselection so that we know which
+ * target is talking to us.
+ */
+static inline int reconnect_target(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
+{
+       int it, me = esp->scsi_id_mask, targ = 0;
+
+       if(2 != fcount(esp, eregs))
+               return -1;
+       if(esp->erev == fashme) {
+               /* HME does not latch it's own BUS ID bits during
+                * a reselection.  Also the target number is given
+                * as an unsigned char, not as a sole bit number
+                * like the other ESP's do.
+                * Happy Meal indeed....
+                */
+               targ = esp->hme_fifo_workaround_buffer[0];
+       } else {
+               it = eregs->esp_fdata;
+               if(!(it & me))
+                       return -1;
+               it &= ~me;
+               if(it & (it - 1))
+                       return -1;
+               while(!(it & 1))
+                       targ++, it >>= 1;
+       }
+       return targ;
+}
+
+/* This verifies the identify from the target so that we know which lun is
+ * being reconnected.
+ */
+static inline int reconnect_lun(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
+{
+       int lun;
+
+       if((esp->sreg & ESP_STAT_PMASK) != ESP_MIP)
+               return -1;
+       if(esp->erev == fashme)
+               lun = esp->hme_fifo_workaround_buffer[1];
+       else
+               lun = eregs->esp_fdata;
+
+       /* Yes, you read this correctly.  We report lun of zero
+        * if we see parity error.  ESP reports parity error for
+        * the lun byte, and this is the only way to hope to recover
+        * because the target is connected.
+        */
+       if(esp->sreg & ESP_STAT_PERR)
+               return 0;
+
+       /* Check for illegal bits being set in the lun. */
+       if((lun & 0x40) || !(lun & 0x80))
+               return -1;
+
+       return lun & 7;
+}
+
+/* This puts the driver in a state where it can revitalize a command that
+ * is being continued due to reselection.
+ */
+static inline void esp_connect(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                              Scsi_Cmnd *sp)
+{
+       Scsi_Device *dp = sp->device;
+
+       if(esp->prev_soff  != dp->sync_max_offset ||
+          esp->prev_stp   != dp->sync_min_period ||
+          (esp->erev > esp100a &&
+           esp->prev_cfg3 != esp->config3[sp->target])) {
+               eregs->esp_soff = esp->prev_soff = dp->sync_max_offset;
+               eregs->esp_stp  = esp->prev_stp = dp->sync_min_period;
+               if(esp->erev > esp100a)
+                       eregs->esp_cfg3 =
+                               esp->prev_cfg3 =
+                               esp->config3[sp->target];
+       }
+       esp->current_SC = sp;
+}
+
+/* This will place the current working command back into the issue queue
+ * if we are to receive a reselection amidst a selection attempt.
+ */
+static inline void esp_reconnect(struct Sparc_ESP *esp, Scsi_Cmnd *sp)
+{
+       if(!esp->disconnected_SC)
+               ESPLOG(("esp%d: Weird, being reselected but disconnected "
+                       "command queue is empty.\n", esp->esp_id));
+       esp->snip = 0;
+       esp->current_SC = 0;
+       sp->SCp.phase = not_issued;
+       append_SC(&esp->issue_SC, sp);
+}
+
+/* Begin message in phase. */
+static int esp_do_msgin(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                       struct sparc_dma_registers *dregs)
+{
+       /* Must be very careful with the fifo on the HME */
+       if((esp->erev != fashme) || !(eregs->esp_status2 & ESP_STAT2_FEMPTY))
+               esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+       esp_maybe_nop(esp, eregs);
+       esp_cmd(esp, eregs, ESP_CMD_TI);
+       esp->msgin_len = 1;
+       esp->msgin_ctr = 0;
+       esp_advance_phase(esp->current_SC, in_msgindone);
+       return do_work_bus;
+}
+
+/* This uses various DMA csr fields and the fifo flags count value to
+ * determine how many bytes were successfully sent/received by the ESP.
+ */
+static inline int esp_bytes_sent(struct Sparc_ESP *esp,
+                                struct sparc_dma_registers *dregs,
+                                int fifo_count)
+{
+       int rval = dregs->st_addr - esp->esp_command_dvma;
+
+       if(esp->dma->revision == dvmarev1)
+               rval -= (4 - ((dregs->cond_reg & DMA_READ_AHEAD)>>11));
+       return rval - fifo_count;
+}
+
+static inline void advance_sg(Scsi_Cmnd *sp)
+{
+       ++sp->SCp.buffer;
+       --sp->SCp.buffers_residual;
+       sp->SCp.this_residual = sp->SCp.buffer->length;
+       sp->SCp.ptr = (char *)((unsigned long)sp->SCp.buffer->dvma_address);
+}
+
+/* Please note that the way I've coded these routines is that I _always_
+ * check for a disconnect during any and all information transfer
+ * phases.  The SCSI standard states that the target _can_ cause a BUS
+ * FREE condition by dropping all MSG/CD/IO/BSY signals.  Also note
+ * that during information transfer phases the target controls every
+ * change in phase, the only thing the initiator can do is "ask" for
+ * a message out phase by driving ATN true.  The target can, and sometimes
+ * will, completely ignore this request so we cannot assume anything when
+ * we try to force a message out phase to abort/reset a target.  Most of
+ * the time the target will eventually be nice and go to message out, so
+ * we may have to hold on to our state about what we want to tell the target
+ * for some period of time.
+ */
+
+/* I think I have things working here correctly.  Even partial transfers
+ * within a buffer or sub-buffer should not upset us at all no matter
+ * how bad the target and/or ESP fucks things up.
+ */
+static int esp_do_data(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                      struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+       int thisphase, hmuch;
+
+       ESPDATA(("esp_do_data: "));
+       esp_maybe_nop(esp, eregs);
+       thisphase = sreg_to_dataphase(esp->sreg);
+       esp_advance_phase(SCptr, thisphase);
+       ESPDATA(("newphase<%s> ", (thisphase == in_datain) ? "DATAIN" : "DATAOUT"));
+       hmuch = dma_can_transfer(SCptr, esp->dma->revision);
+       ESPDATA(("hmuch<%d> ", hmuch));
+       esp->current_transfer_size = hmuch;
+       if(esp->erev == fashme) {
+               unsigned long tmp = esp->prev_hme_dmacsr;
+
+               /* Always set the ESP count registers first. */
+               esp_setcount(eregs, hmuch, 1);
+
+               /* Get the DMA csr computed. */
+               tmp |= (DMA_SCSI_DISAB | DMA_ENABLE);
+               if (thisphase == in_datain)
+                       tmp |= DMA_ST_WRITE;
+               else
+                       tmp &= ~(DMA_ST_WRITE);
+               esp->prev_hme_dmacsr = tmp;
+
+               if (thisphase == in_datain) {
+                       dregs->cnt = hmuch;
+                       esp_cmd(esp, eregs, ESP_CMD_DMA | ESP_CMD_TI);
+               } else {
+                       esp_cmd(esp, eregs, ESP_CMD_DMA | ESP_CMD_TI);
+                       dregs->cnt = hmuch;
+               }
+               dregs->st_addr = ((__u32)((unsigned long)SCptr->SCp.ptr));
+               dregs->cond_reg = esp->prev_hme_dmacsr;
+       } else {
+               esp_setcount(eregs, hmuch, 0);
+               dma_setup(dregs, esp->dma->revision,
+                         ((__u32)((unsigned long)SCptr->SCp.ptr)),
+                         hmuch, (thisphase == in_datain));
+               ESPDATA(("DMA|TI --> do_intr_end\n"));
+               esp_cmd(esp, eregs, ESP_CMD_DMA | ESP_CMD_TI);
+       }
+       return do_intr_end;
+}
+
+/* See how successful the data transfer was. */
+static int esp_do_data_finale(struct Sparc_ESP *esp,
+                             struct Sparc_ESP_regs *eregs,
+                             struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+       int bogus_data = 0, bytes_sent = 0, fifocnt, ecount = 0;
+
+       ESPDATA(("esp_do_data_finale: "));
+
+       if(SCptr->SCp.phase == in_datain) {
+               if(esp->sreg & ESP_STAT_PERR) {
+                       /* Yuck, parity error.  The ESP asserts ATN
+                        * so that we can go to message out phase
+                        * immediately and inform the target that
+                        * something bad happened.
+                        */
+                       ESPLOG(("esp%d: data bad parity detected.\n",
+                               esp->esp_id));
+                       esp->cur_msgout[0] = INITIATOR_ERROR;
+                       esp->msgout_len = 1;
+               }
+               dma_drain(dregs, esp->dma->revision);
+       }
+       dma_invalidate(esp, dregs, esp->dma->revision);
+
+       /* This could happen for the above parity error case. */
+       if(!(esp->ireg == ESP_INTR_BSERV)) {
+               /* Please go to msgout phase, please please please... */
+               ESPLOG(("esp%d: !BSERV after data, probably to msgout\n",
+                       esp->esp_id));
+               return esp_do_phase_determine(esp, eregs, dregs);
+       }       
+
+       /* Check for partial transfers and other horrible events.
+        * Note, here we read the real fifo flags register even
+        * on HME broken adapters because we skip the HME fifo
+        * workaround code in esp_handle() if we are doing data
+        * phase things.  We don't want to fuck directly with
+        * the fifo like that, especially if doing syncronous
+        * transfers!  Also, will need to double the count on
+        * HME if we are doing wide transfers, as the HME fifo
+        * will move and count 16-bit quantities during wide data.
+        * SMCC _and_ Qlogic can both bite me.
+        */
+       fifocnt = eregs->esp_fflags & ESP_FF_FBYTES;
+       if(esp->erev != fashme)
+               ecount = esp_getcount(eregs);
+       bytes_sent = esp->current_transfer_size;
+
+       ESPDATA(("trans_sz=%d, ", bytes_sent));
+       if(esp->erev == fashme) {
+               if(!(esp->sreg & ESP_STAT_TCNT)) {
+                       ecount = esp_getcount(eregs);
+                       bytes_sent -= ecount;
+               }
+
+               /* Always subtract any cruft remaining in the FIFO. */
+               if(esp->prev_cfg3 & ESP_CONFIG3_EWIDE)
+                       fifocnt <<= 1;
+               if(SCptr->SCp.phase == in_dataout)
+                       bytes_sent -= fifocnt;
+
+               /* I have an IBM disk which exhibits the following
+                * behavior during writes to it.  It disconnects in
+                * the middle of a partial transfer, the current sglist
+                * buffer is 1024 bytes, the disk stops data transfer
+                * at 512 bytes.
+                *
+                * However the FAS366 reports that 32 more bytes were
+                * transferred than really were.  This is precisely
+                * the size of a fully loaded FIFO in wide scsi mode.
+                * The FIFO state recorded indicates that it is empty.
+                *
+                * I have no idea if this is a bug in the FAS366 chip
+                * or a bug in the firmware on this IBM disk.  In any
+                * event the following seems to be a good workaround.  -DaveM
+                */
+               if (bytes_sent != esp->current_transfer_size &&
+                   SCptr->SCp.phase == in_dataout) {
+                       int mask = (64 - 1);
+
+                       if((esp->prev_cfg3 & ESP_CONFIG3_EWIDE) == 0)
+                               mask >>= 1;
+
+                       if (bytes_sent & mask)
+                               bytes_sent -= (bytes_sent & mask);
+               }
+       } else {
+               if(!(esp->sreg & ESP_STAT_TCNT))
+                       bytes_sent -= ecount;
+               if(SCptr->SCp.phase == in_dataout)
+                       bytes_sent -= fifocnt;
+       }
+
+       ESPDATA(("bytes_sent=%d, ", bytes_sent));
+
+       /* If we were in synchronous mode, check for peculiarities. */
+       if(esp->erev == fashme) {
+               if(SCptr->device->sync_max_offset) {
+                       if(SCptr->SCp.phase == in_dataout)
+                               esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+               } else {
+                       esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+               }
+       } else {
+               if(SCptr->device->sync_max_offset)
+                       bogus_data = esp100_sync_hwbug(esp, eregs, SCptr, fifocnt);
+               else
+                       esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+       }
+
+       /* Until we are sure of what has happened, we are certainly
+        * in the dark.
+        */
+       esp_advance_phase(SCptr, in_the_dark);
+
+       if(bytes_sent < 0) {
+               /* I've seen this happen due to lost state in this
+                * driver.  No idea why it happened, but allowing
+                * this value to be negative caused things to
+                * lock up.  This allows greater chance of recovery.
+                * In fact every time I've seen this, it has been
+                * a driver bug without question.
+                */
+               ESPLOG(("esp%d: yieee, bytes_sent < 0!\n", esp->esp_id));
+               ESPLOG(("esp%d: csz=%d fifocount=%d ecount=%d\n",
+                       esp->esp_id,
+                       esp->current_transfer_size, fifocnt, ecount));
+               ESPLOG(("esp%d: use_sg=%d ptr=%p this_residual=%d\n",
+                       esp->esp_id,
+                       SCptr->use_sg, SCptr->SCp.ptr, SCptr->SCp.this_residual));
+               ESPLOG(("esp%d: Forcing async for target %d\n", esp->esp_id, 
+                       SCptr->target));
+               SCptr->device->borken = 1;
+               SCptr->device->sync = 0;
+               bytes_sent = 0;
+       }
+
+       /* Update the state of our transfer. */
+       SCptr->SCp.ptr += bytes_sent;
+       SCptr->SCp.this_residual -= bytes_sent;
+       if(SCptr->SCp.this_residual < 0) {
+               /* shit */
+               ESPLOG(("esp%d: Data transfer overrun.\n", esp->esp_id));
+               SCptr->SCp.this_residual = 0;
+       }
+
+       /* Maybe continue. */
+       if(!bogus_data) {
+               ESPDATA(("!bogus_data, "));
+               /* NO MATTER WHAT, we advance the scatterlist,
+                * if the target should decide to disconnect
+                * in between scatter chunks (which is common)
+                * we could die horribly!  I used to have the sg
+                * advance occur only if we are going back into
+                * (or are staying in) a data phase, you can
+                * imagine the hell I went through trying to
+                * figure this out.
+                */
+               if(SCptr->use_sg && !SCptr->SCp.this_residual)
+                       advance_sg(SCptr);
+               if(sreg_datainp(esp->sreg) || sreg_dataoutp(esp->sreg)) {
+                       ESPDATA(("to more data\n"));
+                       return esp_do_data(esp, eregs, dregs);
+               }
+               ESPDATA(("to new phase\n"));
+               return esp_do_phase_determine(esp, eregs, dregs);
+       }
+       /* Bogus data, just wait for next interrupt. */
+       ESPLOG(("esp%d: bogus_data during end of data phase\n",
+               esp->esp_id));
+       return do_intr_end;
+}
+
+/* We received a non-good status return at the end of
+ * running a SCSI command.  This is used to decide if
+ * we should clear our synchronous transfer state for
+ * such a device when that happens.
+ *
+ * The idea is that when spinning up a disk or rewinding
+ * a tape, we don't want to go into a loop re-negotiating
+ * synchronous capabilities over and over.
+ */
+static int esp_should_clear_sync(Scsi_Cmnd *sp)
+{
+       unchar cmd1 = sp->cmnd[0];
+       unchar cmd2 = sp->data_cmnd[0];
+
+       /* These cases are for spinning up a disk and
+        * waiting for that spinup to complete.
+        */
+       if(cmd1 == START_STOP ||
+          cmd2 == START_STOP)
+               return 0;
+
+       if(cmd1 == TEST_UNIT_READY ||
+          cmd2 == TEST_UNIT_READY)
+               return 0;
+
+       /* One more special case for SCSI tape drives,
+        * this is what is used to probe the device for
+        * completion of a rewind or tape load operation.
+        */
+       if(sp->device->type == TYPE_TAPE) {
+               if(cmd1 == MODE_SENSE ||
+                  cmd2 == MODE_SENSE)
+                       return 0;
+       }
+
+       return 1;
+}
+
+/* Either a command is completing or a target is dropping off the bus
+ * to continue the command in the background so we can do other work.
+ */
+static int esp_do_freebus(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                         struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+       int rval;
+
+       rval = skipahead2(esp, eregs, dregs, SCptr, in_status, in_msgindone, in_freeing);
+       if(rval)
+               return rval;
+       if(esp->ireg != ESP_INTR_DC) {
+               ESPLOG(("esp%d: Target will not disconnect\n", esp->esp_id));
+               return do_reset_bus; /* target will not drop BSY... */
+       }
+       esp->msgout_len = 0;
+       esp->prevmsgout = NOP;
+       if(esp->prevmsgin == COMMAND_COMPLETE) {
+               /* Normal end of nexus. */
+               if(esp->disconnected_SC || (esp->erev == fashme))
+                       esp_cmd(esp, eregs, ESP_CMD_ESEL);
+
+               if(SCptr->SCp.Status != GOOD &&
+                  SCptr->SCp.Status != CONDITION_GOOD &&
+                  ((1<<SCptr->target) & esp->targets_present) &&
+                  SCptr->device->sync &&
+                  SCptr->device->sync_max_offset) {
+                       /* SCSI standard says that the synchronous capabilities
+                        * should be renegotiated at this point.  Most likely
+                        * we are about to request sense from this target
+                        * in which case we want to avoid using sync
+                        * transfers until we are sure of the current target
+                        * state.
+                        */
+                       ESPMISC(("esp: Status <%d> for target %d lun %d\n",
+                                SCptr->SCp.Status, SCptr->target, SCptr->lun));
+
+                       /* But don't do this when spinning up a disk at
+                        * boot time while we poll for completion as it
+                        * fills up the console with messages.  Also, tapes
+                        * can report not ready many times right after
+                        * loading up a tape.
+                        */
+                       if(esp_should_clear_sync(SCptr) != 0)
+                               SCptr->device->sync = 0;
+               }
+               ESPDISC(("F<%02x,%02x>", SCptr->target, SCptr->lun));
+               esp_done(esp, ((SCptr->SCp.Status & 0xff) |
+                              ((SCptr->SCp.Message & 0xff)<<8) |
+                              (DID_OK << 16)));
+       } else if(esp->prevmsgin == DISCONNECT) {
+               /* Normal disconnect. */
+               esp_cmd(esp, eregs, ESP_CMD_ESEL);
+               ESPDISC(("D<%02x,%02x>", SCptr->target, SCptr->lun));
+               append_SC(&esp->disconnected_SC, SCptr);
+               esp->current_SC = NULL;
+               if(esp->issue_SC)
+                       esp_exec_cmd(esp);
+       } else {
+               /* Driver bug, we do not expect a disconnect here
+                * and should not have advanced the state engine
+                * to in_freeing.
+                */
+               ESPLOG(("esp%d: last msg not disc and not cmd cmplt.\n",
+                       esp->esp_id));
+               return do_reset_bus;
+       }
+       return do_intr_end;
+}
+
+/* When a reselect occurs, and we cannot find the command to
+ * reconnect to in our queues, we do this.
+ */
+static int esp_bad_reconnect(struct Sparc_ESP *esp)
+{
+       Scsi_Cmnd *sp;
+
+       ESPLOG(("esp%d: Eieeee, reconnecting unknown command!\n",
+               esp->esp_id));
+       ESPLOG(("QUEUE DUMP\n"));
+       sp = esp->issue_SC;
+       ESPLOG(("esp%d: issue_SC[", esp->esp_id));
+       while(sp) {
+               ESPLOG(("<%02x,%02x>", sp->target, sp->lun));
+               sp = (Scsi_Cmnd *) sp->host_scribble;
+       }
+       ESPLOG(("]\n"));
+       sp = esp->current_SC;
+       ESPLOG(("esp%d: current_SC[", esp->esp_id));
+       while(sp) {
+               ESPLOG(("<%02x,%02x>", sp->target, sp->lun));
+               sp = (Scsi_Cmnd *) sp->host_scribble;
+       }
+       ESPLOG(("]\n"));
+       sp = esp->disconnected_SC;
+       ESPLOG(("esp%d: disconnected_SC[", esp->esp_id));
+       while(sp) {
+               ESPLOG(("<%02x,%02x>", sp->target, sp->lun));
+               sp = (Scsi_Cmnd *) sp->host_scribble;
+       }
+       ESPLOG(("]\n"));
+       return do_reset_bus;
+}
+
+/* Do the needy when a target tries to reconnect to us. */
+static int esp_do_reconnect(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                           struct sparc_dma_registers *dregs)
+{
+       int lun, target;
+       Scsi_Cmnd *SCptr;
+
+       /* Check for all bogus conditions first. */
+       target = reconnect_target(esp, eregs);
+       if(target < 0) {
+               ESPDISC(("bad bus bits\n"));
+               return do_reset_bus;
+       }
+       lun = reconnect_lun(esp, eregs);
+       if(lun < 0) {
+               ESPDISC(("target=%2x, bad identify msg\n", target));
+               return do_reset_bus;
+       }
+
+       /* Things look ok... */
+       ESPDISC(("R<%02x,%02x>", target, lun));
+
+       /* Must not flush FIFO or DVMA on HME. */
+       if(esp->erev != fashme) {
+               esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+               if(esp100_reconnect_hwbug(esp, eregs))
+                       return do_reset_bus;
+               esp_cmd(esp, eregs, ESP_CMD_NULL);
+       }
+
+       SCptr = remove_SC(&esp->disconnected_SC, (unchar) target, (unchar) lun);
+       if(!SCptr)
+               return esp_bad_reconnect(esp);
+
+       esp_connect(esp, eregs, SCptr);
+       esp_cmd(esp, eregs, ESP_CMD_MOK);
+
+       if(esp->erev == fashme)
+               eregs->esp_busid = (SCptr->target & 0xf) |
+                       (ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT);
+
+       /* Reconnect implies a restore pointers operation. */
+       esp_restore_pointers(esp, SCptr);
+
+       esp->snip = 0;
+       esp_advance_phase(SCptr, in_the_dark);
+       return do_intr_end;
+}
+
+/* End of NEXUS (hopefully), pick up status + message byte then leave if
+ * all goes well.
+ */
+static int esp_do_status(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                        struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+       int intr, rval;
+
+       rval = skipahead1(esp, eregs, dregs, SCptr, in_the_dark, in_status);
+       if(rval)
+               return rval;
+       intr = esp->ireg;
+       ESPSTAT(("esp_do_status: "));
+       if(intr != ESP_INTR_DC) {
+               int message_out = 0; /* for parity problems */
+
+               /* Ack the message. */
+               ESPSTAT(("ack msg, "));
+               esp_cmd(esp, eregs, ESP_CMD_MOK);
+
+               if(esp->erev != fashme) {
+                       dma_flashclear(esp, dregs, esp->dma->revision);
+
+                       /* Wait till the first bits settle. */
+                       while(esp->esp_command[0] == 0xff)
+                               udelay(1);
+               } else {
+                       esp->esp_command[0] = esp->hme_fifo_workaround_buffer[0];
+                       esp->esp_command[1] = esp->hme_fifo_workaround_buffer[1];
+               }
+
+               ESPSTAT(("got something, "));
+               /* ESP chimes in with one of
+                *
+                * 1) function done interrupt:
+                *      both status and message in bytes
+                *      are available
+                *
+                * 2) bus service interrupt:
+                *      only status byte was acquired
+                *
+                * 3) Anything else:
+                *      can't happen, but we test for it
+                *      anyways
+                *
+                * ALSO: If bad parity was detected on either
+                *       the status _or_ the message byte then
+                *       the ESP has asserted ATN on the bus
+                *       and we must therefore wait for the
+                *       next phase change.
+                */
+               if(intr & ESP_INTR_FDONE) {
+                       /* We got it all, hallejulia. */
+                       ESPSTAT(("got both, "));
+                       SCptr->SCp.Status = esp->esp_command[0];
+                       SCptr->SCp.Message = esp->esp_command[1];
+                       esp->prevmsgin = SCptr->SCp.Message;
+                       esp->cur_msgin[0] = SCptr->SCp.Message;
+                       if(esp->sreg & ESP_STAT_PERR) {
+                               /* There was bad parity for the
+                                * message byte, the status byte
+                                * was ok.
+                                */
+                               message_out = MSG_PARITY_ERROR;
+                       }
+               } else if(intr == ESP_INTR_BSERV) {
+                       /* Only got status byte. */
+                       ESPLOG(("esp%d: got status only, ", esp->esp_id));
+                       if(!(esp->sreg & ESP_STAT_PERR)) {
+                               SCptr->SCp.Status = esp->esp_command[0];
+                               SCptr->SCp.Message = 0xff;
+                       } else {
+                               /* The status byte had bad parity.
+                                * we leave the scsi_pointer Status
+                                * field alone as we set it to a default
+                                * of CHECK_CONDITION in esp_queue.
+                                */
+                               message_out = INITIATOR_ERROR;
+                       }
+               } else {
+                       /* This shouldn't happen ever. */
+                       ESPSTAT(("got bolixed\n"));
+                       esp_advance_phase(SCptr, in_the_dark);
+                       return esp_do_phase_determine(esp, eregs, dregs);
+               }
+
+               if(!message_out) {
+                       ESPSTAT(("status=%2x msg=%2x, ", SCptr->SCp.Status,
+                               SCptr->SCp.Message));
+                       if(SCptr->SCp.Message == COMMAND_COMPLETE) {
+                               ESPSTAT(("and was COMMAND_COMPLETE\n"));
+                               esp_advance_phase(SCptr, in_freeing);
+                               return esp_do_freebus(esp, eregs, dregs);
+                       } else {
+                               ESPLOG(("esp%d: and _not_ COMMAND_COMPLETE\n",
+                                       esp->esp_id));
+                               esp->msgin_len = esp->msgin_ctr = 1;
+                               esp_advance_phase(SCptr, in_msgindone);
+                               return esp_do_msgindone(esp, eregs, dregs);
+                       }
+               } else {
+                       /* With luck we'll be able to let the target
+                        * know that bad parity happened, it will know
+                        * which byte caused the problems and send it
+                        * again.  For the case where the status byte
+                        * receives bad parity, I do not believe most
+                        * targets recover very well.  We'll see.
+                        */
+                       ESPLOG(("esp%d: bad parity somewhere mout=%2x\n",
+                               esp->esp_id, message_out));
+                       esp->cur_msgout[0] = message_out;
+                       esp->msgout_len = esp->msgout_ctr = 1;
+                       esp_advance_phase(SCptr, in_the_dark);
+                       return esp_do_phase_determine(esp, eregs, dregs);
+               }
+       } else {
+               /* If we disconnect now, all hell breaks loose. */
+               ESPLOG(("esp%d: whoops, disconnect\n", esp->esp_id));
+               esp_advance_phase(SCptr, in_the_dark);
+               return esp_do_phase_determine(esp, eregs, dregs);
+       }
+}
+
+static int esp_enter_status(struct Sparc_ESP *esp,
+                           struct Sparc_ESP_regs *eregs,
+                           struct sparc_dma_registers *dregs)
+{
+       unchar thecmd = ESP_CMD_ICCSEQ;
+
+       esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+       if(esp->erev != fashme) {
+               esp->esp_command[0] = esp->esp_command[1] = 0xff;
+               eregs->esp_tclow = 2;
+               eregs->esp_tcmed = 0;
+               dregs->cond_reg |= (DMA_ST_WRITE | DMA_ENABLE);
+               if(esp->dma->revision == dvmaesc1)
+                       dregs->cnt = 0x100;
+               dregs->st_addr = esp->esp_command_dvma;
+               thecmd |= ESP_CMD_DMA;
+       }
+       esp_cmd(esp, eregs, thecmd);
+       esp_advance_phase(esp->current_SC, in_status);
+
+       return esp_do_status(esp, eregs, dregs);
+}
+
+static int esp_disconnect_amidst_phases(struct Sparc_ESP *esp,
+                                       struct Sparc_ESP_regs *eregs,
+                                       struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *sp = esp->current_SC;
+       Scsi_Device *dp = sp->device;
+
+       /* This means real problems if we see this
+        * here.  Unless we were actually trying
+        * to force the device to abort/reset.
+        */
+       ESPLOG(("esp%d Disconnect amidst phases, ", esp->esp_id));
+       ESPLOG(("pphase<%s> cphase<%s>, ",
+               phase_string(sp->SCp.phase),
+               phase_string(sp->SCp.sent_command)));
+
+       if(esp->disconnected_SC || (esp->erev == fashme))
+               esp_cmd(esp, eregs, ESP_CMD_ESEL);
+
+       switch(esp->cur_msgout[0]) {
+       default:
+               /* We didn't expect this to happen at all. */
+               ESPLOG(("device is bolixed\n"));
+               esp_advance_phase(sp, in_tgterror);
+               esp_done(esp, (DID_ERROR << 16));
+               break;
+
+       case BUS_DEVICE_RESET:
+               ESPLOG(("device reset successful\n"));
+               dp->sync_max_offset = 0;
+               dp->sync_min_period = 0;
+               dp->sync = 0;
+               esp_advance_phase(sp, in_resetdev);
+               esp_done(esp, (DID_RESET << 16));
+               break;
+
+       case ABORT:
+               ESPLOG(("device abort successful\n"));
+               esp_advance_phase(sp, in_abortone);
+               esp_done(esp, (DID_ABORT << 16));
+               break;
+
+       };
+       return do_intr_end;
+}
+
+static int esp_enter_msgout(struct Sparc_ESP *esp,
+                           struct Sparc_ESP_regs *eregs,
+                           struct sparc_dma_registers *dregs)
+{
+       esp_advance_phase(esp->current_SC, in_msgout);
+       return esp_do_msgout(esp, eregs, dregs);
+}
+
+static int esp_enter_msgin(struct Sparc_ESP *esp,
+                          struct Sparc_ESP_regs *eregs,
+                          struct sparc_dma_registers *dregs)
+{
+       esp_advance_phase(esp->current_SC, in_msgin);
+       return esp_do_msgin(esp, eregs, dregs);
+}
+
+static int esp_enter_cmd(struct Sparc_ESP *esp,
+                        struct Sparc_ESP_regs *eregs,
+                        struct sparc_dma_registers *dregs)
+{
+       esp_advance_phase(esp->current_SC, in_cmdbegin);
+       return esp_do_cmdbegin(esp, eregs, dregs);
+}
+
+static int esp_enter_badphase(struct Sparc_ESP *esp,
+                             struct Sparc_ESP_regs *eregs,
+                             struct sparc_dma_registers *dregs)
+{
+       ESPLOG(("esp%d: Bizarre bus phase %2x.\n", esp->esp_id,
+               esp->sreg & ESP_STAT_PMASK));
+       return do_reset_bus;
+}
+
+typedef int (*espfunc_t)(struct Sparc_ESP *,
+                        struct Sparc_ESP_regs *,
+                        struct sparc_dma_registers *);
+
+static espfunc_t phase_vector[] = {
+       esp_do_data,            /* ESP_DOP */
+       esp_do_data,            /* ESP_DIP */
+       esp_enter_cmd,          /* ESP_CMDP */
+       esp_enter_status,       /* ESP_STATP */
+       esp_enter_badphase,     /* ESP_STAT_PMSG */
+       esp_enter_badphase,     /* ESP_STAT_PMSG | ESP_STAT_PIO */
+       esp_enter_msgout,       /* ESP_MOP */
+       esp_enter_msgin,        /* ESP_MIP */
+};
+
+/* The target has control of the bus and we have to see where it has
+ * taken us.
+ */
+static int esp_do_phase_determine(struct Sparc_ESP *esp,
+                                 struct Sparc_ESP_regs *eregs,
+                                 struct sparc_dma_registers *dregs)
+{
+       if ((esp->ireg & ESP_INTR_DC) != 0)
+               return esp_disconnect_amidst_phases(esp, eregs, dregs);
+       return phase_vector[esp->sreg & ESP_STAT_PMASK](esp, eregs, dregs);
+}
+
+/* First interrupt after exec'ing a cmd comes here. */
+static int esp_select_complete(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                              struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+       Scsi_Device *SDptr = SCptr->device;
+       int cmd_bytes_sent, fcnt;
+
+       if(esp->erev != fashme)
+               esp->seqreg = (eregs->esp_sstep & ESP_STEP_VBITS);
+       if(esp->erev == fashme)
+               fcnt = esp->hme_fifo_workaround_count;
+       else
+               fcnt = (eregs->esp_fflags & ESP_FF_FBYTES);
+       cmd_bytes_sent = esp_bytes_sent(esp, dregs, fcnt);
+       dma_invalidate(esp, dregs, esp->dma->revision);
+
+       /* Let's check to see if a reselect happened
+        * while we we're trying to select.  This must
+        * be checked first.
+        */
+       if(esp->ireg == (ESP_INTR_RSEL | ESP_INTR_FDONE)) {
+               esp_reconnect(esp, SCptr);
+               return esp_do_reconnect(esp, eregs, dregs);
+       }
+
+       /* Looks like things worked, we should see a bus service &
+        * a function complete interrupt at this point.  Note we
+        * are doing a direct comparison because we don't want to
+        * be fooled into thinking selection was successful if
+        * ESP_INTR_DC is set, see below.
+        */
+       if(esp->ireg == (ESP_INTR_FDONE | ESP_INTR_BSERV)) {
+               /* target speaks... */
+               esp->targets_present |= (1<<SCptr->target);
+
+               /* What if the target ignores the sdtr? */
+               if(esp->snip)
+                       SDptr->sync = 1;
+
+               /* See how far, if at all, we got in getting
+                * the information out to the target.
+                */
+               switch(esp->seqreg) {
+               default:
+
+               case ESP_STEP_ASEL:
+                       /* Arbitration won, target selected, but
+                        * we are in some phase which is not command
+                        * phase nor is it message out phase.
+                        *
+                        * XXX We've confused the target, obviously.
+                        * XXX So clear it's state, but we also end
+                        * XXX up clearing everyone elses.  That isn't
+                        * XXX so nice.  I'd like to just reset this
+                        * XXX target, but if I cannot even get it's
+                        * XXX attention and finish selection to talk
+                        * XXX to it, there is not much more I can do.
+                        * XXX If we have a loaded bus we're going to
+                        * XXX spend the next second or so renegotiating
+                        * XXX for synchronous transfers.
+                        */
+                       ESPLOG(("esp%d: STEP_ASEL for tgt %d\n",
+                               esp->esp_id, SCptr->target));
+
+               case ESP_STEP_SID:
+                       /* Arbitration won, target selected, went
+                        * to message out phase, sent one message
+                        * byte, then we stopped.  ATN is asserted
+                        * on the SCSI bus and the target is still
+                        * there hanging on.  This is a legal
+                        * sequence step if we gave the ESP a select
+                        * and stop command.
+                        *
+                        * XXX See above, I could set the borken flag
+                        * XXX in the device struct and retry the
+                        * XXX command.  But would that help for
+                        * XXX tagged capable targets?
+                        */
+
+               case ESP_STEP_NCMD:
+                       /* Arbitration won, target selected, maybe
+                        * sent the one message byte in message out
+                        * phase, but we did not go to command phase
+                        * in the end.  Actually, we could have sent
+                        * only some of the message bytes if we tried
+                        * to send out the entire identify and tag
+                        * message using ESP_CMD_SA3.
+                        */
+                       cmd_bytes_sent = 0;
+                       break;
+
+               case ESP_STEP_PPC:
+                       /* No, not the powerPC pinhead.  Arbitration
+                        * won, all message bytes sent if we went to
+                        * message out phase, went to command phase
+                        * but only part of the command was sent.
+                        *
+                        * XXX I've seen this, but usually in conjunction
+                        * XXX with a gross error which appears to have
+                        * XXX occurred between the time I told the
+                        * XXX ESP to arbitrate and when I got the
+                        * XXX interrupt.  Could I have misloaded the
+                        * XXX command bytes into the fifo?  Actually,
+                        * XXX I most likely missed a phase, and therefore
+                        * XXX went into never never land and didn't even
+                        * XXX know it.  That was the old driver though.
+                        * XXX What is even more peculiar is that the ESP
+                        * XXX showed the proper function complete and
+                        * XXX bus service bits in the interrupt register.
+                        */
+
+               case ESP_STEP_FINI4:
+               case ESP_STEP_FINI5:
+               case ESP_STEP_FINI6:
+               case ESP_STEP_FINI7:
+                       /* Account for the identify message */
+                       if(SCptr->SCp.phase == in_slct_norm)
+                               cmd_bytes_sent -= 1;
+               };
+               if(esp->erev != fashme)
+                       esp_cmd(esp, eregs, ESP_CMD_NULL);
+
+               /* Be careful, we could really get fucked during synchronous
+                * data transfers if we try to flush the fifo now.
+                */
+               if((esp->erev != fashme) && /* not a Happy Meal and... */
+                  !fcnt && /* Fifo is empty and... */
+                  /* either we are not doing synchronous transfers or... */
+                  (!SDptr->sync_max_offset ||
+                   /* We are not going into data in phase. */
+                   ((esp->sreg & ESP_STAT_PMASK) != ESP_DIP)))
+                       esp_cmd(esp, eregs, ESP_CMD_FLUSH); /* flush is safe */
+
+               /* See how far we got if this is not a slow command. */
+               if(!esp->esp_slowcmd) {
+                       if(cmd_bytes_sent < 0)
+                               cmd_bytes_sent = 0;
+                       if(cmd_bytes_sent != SCptr->cmd_len) {
+                               /* Crapola, mark it as a slowcmd
+                                * so that we have some chance of
+                                * keeping the command alive with
+                                * good luck.
+                                *
+                                * XXX Actually, if we didn't send it all
+                                * XXX this means either we didn't set things
+                                * XXX up properly (driver bug) or the target
+                                * XXX or the ESP detected parity on one of
+                                * XXX the command bytes.  This makes much
+                                * XXX more sense, and therefore this code
+                                * XXX should be changed to send out a
+                                * XXX parity error message or if the status
+                                * XXX register shows no parity error then
+                                * XXX just expect the target to bring the
+                                * XXX bus into message in phase so that it
+                                * XXX can send us the parity error message.
+                                * XXX SCSI sucks...
+                                */
+                               esp->esp_slowcmd = 1;
+                               esp->esp_scmdp = &(SCptr->cmnd[cmd_bytes_sent]);
+                               esp->esp_scmdleft = (SCptr->cmd_len - cmd_bytes_sent);
+                       }
+               }
+
+               /* Now figure out where we went. */
+               esp_advance_phase(SCptr, in_the_dark);
+               return esp_do_phase_determine(esp, eregs, dregs);
+       }
+
+       /* Did the target even make it? */
+       if(esp->ireg == ESP_INTR_DC) {
+               /* wheee... nobody there or they didn't like
+                * what we told it to do, clean up.
+                */
+
+               /* If anyone is off the bus, but working on
+                * a command in the background for us, tell
+                * the ESP to listen for them.
+                */
+               if(esp->disconnected_SC)
+                       esp_cmd(esp, eregs, ESP_CMD_ESEL);
+
+               if(((1<<SCptr->target) & esp->targets_present) &&
+                  esp->seqreg && esp->cur_msgout[0] == EXTENDED_MESSAGE &&
+                  (SCptr->SCp.phase == in_slct_msg ||
+                   SCptr->SCp.phase == in_slct_stop)) {
+                       /* shit */
+                       esp->snip = 0;
+                       ESPLOG(("esp%d: Failed synchronous negotiation for target %d "
+                               "lun %d\n", esp->esp_id, SCptr->target, SCptr->lun));
+                       SDptr->sync_max_offset = 0;
+                       SDptr->sync_min_period = 0;
+                       SDptr->sync = 1; /* so we don't negotiate again */
+
+                       /* Run the command again, this time though we
+                        * won't try to negotiate for synchronous transfers.
+                        *
+                        * XXX I'd like to do something like send an
+                        * XXX INITIATOR_ERROR or ABORT message to the
+                        * XXX target to tell it, "Sorry I confused you,
+                        * XXX please come back and I will be nicer next
+                        * XXX time".  But that requires having the target
+                        * XXX on the bus, and it has dropped BSY on us.
+                        */
+                       esp->current_SC = NULL;
+                       esp_advance_phase(SCptr, not_issued);
+                       prepend_SC(&esp->issue_SC, SCptr);
+                       esp_exec_cmd(esp);
+                       return do_intr_end;
+               }
+
+               /* Ok, this is normal, this is what we see during boot
+                * or whenever when we are scanning the bus for targets.
+                * But first make sure that is really what is happening.
+                */
+               if(((1<<SCptr->target) & esp->targets_present)) {
+                       ESPLOG(("esp%d: Warning, live target %d not responding to "
+                               "selection.\n", esp->esp_id, SCptr->target));
+
+                       /* This _CAN_ happen.  The SCSI standard states that
+                        * the target is to _not_ respond to selection if
+                        * _it_ detects bad parity on the bus for any reason.
+                        * Therefore, we assume that if we've talked successfully
+                        * to this target before, bad parity is the problem.
+                        */
+                       esp_done(esp, (DID_PARITY << 16));
+               } else {
+                       /* Else, there really isn't anyone there. */
+                       ESPMISC(("esp: selection failure, maybe nobody there?\n"));
+                       ESPMISC(("esp: target %d lun %d\n",
+                                SCptr->target, SCptr->lun));
+                       esp_done(esp, (DID_BAD_TARGET << 16));
+               }
+               return do_intr_end;
+       }
+
+
+       ESPLOG(("esp%d: Selection failure.\n", esp->esp_id));
+       printk("esp%d: Currently -- ", esp->esp_id);
+       esp_print_ireg(esp->ireg);
+       printk(" ");
+       esp_print_statreg(esp->sreg);
+       printk(" ");
+       esp_print_seqreg(esp->seqreg);
+       printk("\n");
+       printk("esp%d: New -- ", esp->esp_id);
+       esp->sreg = eregs->esp_status;
+       esp->seqreg = eregs->esp_sstep;
+       esp->ireg = eregs->esp_intrpt;
+       esp_print_ireg(esp->ireg);
+       printk(" ");
+       esp_print_statreg(esp->sreg);
+       printk(" ");
+       esp_print_seqreg(esp->seqreg);
+       printk("\n");
+       ESPLOG(("esp%d: resetting bus\n", esp->esp_id));
+       return do_reset_bus; /* ugh... */
+}
+
+/* Continue reading bytes for msgin phase. */
+static int esp_do_msgincont(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                           struct sparc_dma_registers *dregs)
+{
+       if(esp->ireg & ESP_INTR_BSERV) {
+               /* in the right phase too? */
+               if((esp->sreg & ESP_STAT_PMASK) == ESP_MIP) {
+                       /* phew... */
+                       esp_cmd(esp, eregs, ESP_CMD_TI);
+                       esp_advance_phase(esp->current_SC, in_msgindone);
+                       return do_intr_end;
+               }
+
+               /* We changed phase but ESP shows bus service,
+                * in this case it is most likely that we, the
+                * hacker who has been up for 20hrs straight
+                * staring at the screen, drowned in coffee
+                * smelling like retched cigarette ashes
+                * have miscoded something..... so, try to
+                * recover as best we can.
+                */
+               ESPLOG(("esp%d: message in mis-carriage.\n", esp->esp_id));
+       }
+       esp_advance_phase(esp->current_SC, in_the_dark);
+       return do_phase_determine;
+}
+
+static int check_singlebyte_msg(struct Sparc_ESP *esp,
+                               struct Sparc_ESP_regs *eregs,
+                               struct sparc_dma_registers *dregs)
+{
+       esp->prevmsgin = esp->cur_msgin[0];
+       if(esp->cur_msgin[0] & 0x80) {
+               /* wheee... */
+               ESPLOG(("esp%d: target sends identify amidst phases\n",
+                       esp->esp_id));
+               esp_advance_phase(esp->current_SC, in_the_dark);
+               return 0;
+       } else if(((esp->cur_msgin[0] & 0xf0) == 0x20) ||
+                 (esp->cur_msgin[0] == EXTENDED_MESSAGE)) {
+               esp->msgin_len = 2;
+               esp_advance_phase(esp->current_SC, in_msgincont);
+               return 0;
+       }
+       esp_advance_phase(esp->current_SC, in_the_dark);
+       switch(esp->cur_msgin[0]) {
+       default:
+               /* We don't want to hear about it. */
+               ESPLOG(("esp%d: msg %02x which we don't know about\n", esp->esp_id,
+                       esp->cur_msgin[0]));
+               return MESSAGE_REJECT;
+
+       case NOP:
+               ESPLOG(("esp%d: target %d sends a nop\n", esp->esp_id,
+                       esp->current_SC->target));
+               return 0;
+
+       case RESTORE_POINTERS:
+               /* In this case we might also have to backup the
+                * "slow command" pointer.  It is rare to get such
+                * a save/restore pointer sequence so early in the
+                * bus transition sequences, but cover it.
+                */
+               if(esp->esp_slowcmd) {
+                       esp->esp_scmdleft = esp->current_SC->cmd_len;
+                       esp->esp_scmdp = &esp->current_SC->cmnd[0];
+               }
+               esp_restore_pointers(esp, esp->current_SC);
+               return 0;
+
+       case SAVE_POINTERS:
+               esp_save_pointers(esp, esp->current_SC);
+               return 0;
+
+       case COMMAND_COMPLETE:
+       case DISCONNECT:
+               /* Freeing the bus, let it go. */
+               esp->current_SC->SCp.phase = in_freeing;
+               return 0;
+
+       case MESSAGE_REJECT:
+               ESPMISC(("msg reject, "));
+               if(esp->prevmsgout == EXTENDED_MESSAGE) {
+                       Scsi_Device *SDptr = esp->current_SC->device;
+
+                       /* Doesn't look like this target can
+                        * do synchronous or WIDE transfers.
+                        */
+                       ESPSDTR(("got reject, was trying nego, clearing sync/WIDE\n"));
+                       SDptr->sync = 1;
+                       SDptr->wide = 1;
+                       SDptr->sync_min_period = 0;
+                       SDptr->sync_max_offset = 0;
+                       return 0;
+               } else {
+                       ESPMISC(("not sync nego, sending ABORT\n"));
+                       return ABORT;
+               }
+       };
+}
+
+/* Target negotiates for synchronous transfers before we do, this
+ * is legal although very strange.  What is even funnier is that
+ * the SCSI2 standard specifically recommends against targets doing
+ * this because so many initiators cannot cope with this occuring.
+ */
+static int target_with_ants_in_pants(struct Sparc_ESP *esp,
+                                    Scsi_Cmnd *SCptr,
+                                    Scsi_Device *SDptr)
+{
+       if(SDptr->sync || SDptr->borken) {
+               /* sorry, no can do */
+               ESPSDTR(("forcing to async, "));
+               build_sync_nego_msg(esp, 0, 0);
+               SDptr->sync = 1;
+               esp->snip = 1;
+               ESPLOG(("esp%d: hoping for msgout\n", esp->esp_id));
+               esp_advance_phase(SCptr, in_the_dark);
+               return EXTENDED_MESSAGE;
+       }
+
+       /* Ok, we'll check them out... */
+       return 0;
+}
+
+static void sync_report(struct Sparc_ESP *esp)
+{
+       int msg3, msg4;
+       char *type;
+
+       msg3 = esp->cur_msgin[3];
+       msg4 = esp->cur_msgin[4];
+       if(msg4) {
+               int hz = 1000000000 / (msg3 * 4);
+               int integer = hz / 1000000;
+               int fraction = (hz - (integer * 1000000)) / 10000;
+               if((esp->erev == fashme) &&
+                  (esp->config3[esp->current_SC->target] & ESP_CONFIG3_EWIDE)) {
+                       type = "FAST-WIDE";
+                       integer <<= 1;
+                       fraction <<= 1;
+               } else if((msg3 * 4) < 200) {
+                       type = "FAST";
+               } else {
+                       type = "synchronous";
+               }
+
+               /* Do not transform this back into one big printk
+                * again, it triggers a bug in our sparc64-gcc272
+                * sibling call optimization.  -DaveM
+                */
+               ESPLOG((KERN_INFO "esp%d: target %d ",
+                       esp->esp_id, esp->current_SC->target));
+               ESPLOG(("[period %dns offset %d %d.%02dMHz ",
+                       (int) msg3 * 4, (int) msg4,
+                       integer, fraction));
+               ESPLOG(("%s SCSI%s]\n", type,
+                       (((msg3 * 4) < 200) ? "-II" : "")));
+       } else {
+               ESPLOG((KERN_INFO "esp%d: target %d asynchronous\n",
+                       esp->esp_id, esp->current_SC->target));
+       }
+}
+
+static int check_multibyte_msg(struct Sparc_ESP *esp,
+                              struct Sparc_ESP_regs *eregs,
+                              struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+       Scsi_Device *SDptr = SCptr->device;
+       unchar regval = 0;
+       int message_out = 0;
+
+       ESPSDTR(("chk multibyte msg: "));
+       if(esp->cur_msgin[2] == EXTENDED_SDTR) {
+               int period = esp->cur_msgin[3];
+               int offset = esp->cur_msgin[4];
+
+               ESPSDTR(("is sync nego response, "));
+               if(!esp->snip) {
+                       int rval;
+
+                       /* Target negotiates first! */
+                       ESPSDTR(("target jumps the gun, "));
+                       message_out = EXTENDED_MESSAGE; /* we must respond */
+                       rval = target_with_ants_in_pants(esp, SCptr, SDptr);
+                       if(rval)
+                               return rval;
+               }
+
+               ESPSDTR(("examining sdtr, "));
+
+               /* Offset cannot be larger than ESP fifo size. */
+               if(offset > 15) {
+                       ESPSDTR(("offset too big %2x, ", offset));
+                       offset = 15;
+                       ESPSDTR(("sending back new offset\n"));
+                       build_sync_nego_msg(esp, period, offset);
+                       return EXTENDED_MESSAGE;
+               }
+
+               if(offset && period > esp->max_period) {
+                       /* Yeee, async for this slow device. */
+                       ESPSDTR(("period too long %2x, ", period));
+                       build_sync_nego_msg(esp, 0, 0);
+                       ESPSDTR(("hoping for msgout\n"));
+                       esp_advance_phase(esp->current_SC, in_the_dark);
+                       return EXTENDED_MESSAGE;
+               } else if (offset && period < esp->min_period) {
+                       ESPSDTR(("period too short %2x, ", period));
+                       period = esp->min_period;
+                       if(esp->erev > esp236)
+                               regval = 4;
+                       else
+                               regval = 5;
+               } else if(offset) {
+                       int tmp;
+
+                       ESPSDTR(("period is ok, "));
+                       tmp = esp->ccycle / 1000;
+                       regval = (((period << 2) + tmp - 1) / tmp);
+                       if(regval && ((esp->erev == fas100a ||
+                                      esp->erev == fas236 ||
+                                      esp->erev == fashme))) {
+                               if(period >= 50)
+                                       regval--;
+                       }
+               }
+
+               if(offset) {
+                       unchar bit;
+
+                       SDptr->sync_min_period = (regval & 0x1f);
+                       SDptr->sync_max_offset = (offset | esp->radelay);
+                       if((esp->erev == fas100a || esp->erev == fas236 || esp->erev == fashme)) {
+                               if((esp->erev == fas100a) || (esp->erev == fashme))
+                                       bit = ESP_CONFIG3_FAST;
+                               else
+                                       bit = ESP_CONFIG3_FSCSI;
+                               if(period < 50)
+                                       esp->config3[SCptr->target] |= bit;
+                               else
+                                       esp->config3[SCptr->target] &= ~bit;
+                               eregs->esp_cfg3 = esp->prev_cfg3 = esp->config3[SCptr->target];
+                       }
+                       eregs->esp_soff = esp->prev_soff = SDptr->sync_min_period;
+                       eregs->esp_stp  = esp->prev_stp  = SDptr->sync_max_offset;
+
+                       ESPSDTR(("soff=%2x stp=%2x cfg3=%2x\n",
+                               SDptr->sync_max_offset,
+                               SDptr->sync_min_period,
+                               esp->config3[SCptr->target]));
+
+                       esp->snip = 0;
+               } else if(SDptr->sync_max_offset) {
+                       unchar bit;
+
+                       /* back to async mode */
+                       ESPSDTR(("unaccaptable sync nego, forcing async\n"));
+                       SDptr->sync_max_offset = 0;
+                       SDptr->sync_min_period = 0;
+                       eregs->esp_soff = esp->prev_soff = 0;
+                       eregs->esp_stp = esp->prev_stp = 0;
+                       if((esp->erev == fas100a || esp->erev == fas236 || esp->erev == fashme)) {
+                               if((esp->erev == fas100a) || (esp->erev == fashme))
+                                       bit = ESP_CONFIG3_FAST;
+                               else
+                                       bit = ESP_CONFIG3_FSCSI;
+                               esp->config3[SCptr->target] &= ~bit;
+                               eregs->esp_cfg3 = esp->prev_cfg3 = esp->config3[SCptr->target];
+                       }
+               }
+
+               sync_report(esp);
+
+               ESPSDTR(("chk multibyte msg: sync is known, "));
+               SDptr->sync = 1;
+
+               if(message_out) {
+                       ESPLOG(("esp%d: sending sdtr back, hoping for msgout\n",
+                               esp->esp_id));
+                       build_sync_nego_msg(esp, period, offset);
+                       esp_advance_phase(SCptr, in_the_dark);
+                       return EXTENDED_MESSAGE;
+               }
+
+               ESPSDTR(("returning zero\n"));
+               esp_advance_phase(SCptr, in_the_dark); /* ...or else! */
+               return 0;
+       } else if(esp->cur_msgin[2] == EXTENDED_WDTR) {
+               int size = 8 << esp->cur_msgin[3];
+
+               esp->wnip = 0;
+               if(esp->erev != fashme) {
+                       ESPLOG(("esp%d: AIEEE wide msg received and not HME.\n",
+                               esp->esp_id));
+                       message_out = MESSAGE_REJECT;
+               } else if(size > 16) {
+                       ESPLOG(("esp%d: AIEEE wide transfer for %d size "
+                               "not supported.\n", esp->esp_id, size));
+                       message_out = MESSAGE_REJECT;
+               } else {
+                       /* Things look good; let's see what we got. */
+                       if(size == 16) {
+                               /* Set config 3 register for this target. */
+                               esp->config3[SCptr->target] |= ESP_CONFIG3_EWIDE;
+                       } else {
+                               /* Just make sure it was one byte sized. */
+                               if(size != 8) {
+                                       ESPLOG(("esp%d: Aieee, wide nego of %d size.\n",
+                                               esp->esp_id, size));
+                                       message_out = MESSAGE_REJECT;
+                                       goto finish;
+                               }
+                               /* Pure paranoia. */
+                               esp->config3[SCptr->target] &= ~(ESP_CONFIG3_EWIDE);
+                       }
+                       eregs->esp_cfg3 = esp->prev_cfg3 = esp->config3[SCptr->target];
+
+                       /* Regardless, next try for sync transfers. */
+                       build_sync_nego_msg(esp, esp->sync_defp, 15);
+                       SDptr->sync = 1;
+                       esp->snip = 1;
+                       message_out = EXTENDED_MESSAGE;
+               }
+       } else if(esp->cur_msgin[2] == EXTENDED_MODIFY_DATA_POINTER) {
+               ESPLOG(("esp%d: rejecting modify data ptr msg\n", esp->esp_id));
+               message_out = MESSAGE_REJECT;
+       }
+finish:
+       esp_advance_phase(SCptr, in_the_dark);
+       return message_out;
+}
+
+static int esp_do_msgindone(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                           struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+       int message_out = 0, it = 0, rval;
+
+       rval = skipahead1(esp, eregs, dregs, SCptr, in_msgin, in_msgindone);
+       if(rval)
+               return rval;
+       if(SCptr->SCp.sent_command != in_status) {
+               if(!(esp->ireg & ESP_INTR_DC)) {
+                       if(esp->msgin_len && (esp->sreg & ESP_STAT_PERR)) {
+                               message_out = MSG_PARITY_ERROR;
+                               esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+                       } else if(esp->erev != fashme &&
+                                 (it = (eregs->esp_fflags & ESP_FF_FBYTES))!=1) {
+                               /* We certainly dropped the ball somewhere. */
+                               message_out = INITIATOR_ERROR;
+                               esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+                       } else if(!esp->msgin_len) {
+                               if(esp->erev == fashme)
+                                       it = esp->hme_fifo_workaround_buffer[0];
+                               else
+                                       it = eregs->esp_fdata;
+                               esp_advance_phase(SCptr, in_msgincont);
+                       } else {
+                               /* it is ok and we want it */
+                               if(esp->erev == fashme)
+                                       it = esp->cur_msgin[esp->msgin_ctr] =
+                                               esp->hme_fifo_workaround_buffer[0];
+                               else
+                                       it = esp->cur_msgin[esp->msgin_ctr] =
+                                               eregs->esp_fdata;
+                               esp->msgin_ctr++;
+                       }
+               } else {
+                       esp_advance_phase(SCptr, in_the_dark);
+                       return do_work_bus;
+               }
+       } else {
+               it = esp->cur_msgin[0];
+       }
+       if(!message_out && esp->msgin_len) {
+               if(esp->msgin_ctr < esp->msgin_len) {
+                       esp_advance_phase(SCptr, in_msgincont);
+               } else if(esp->msgin_len == 1) {
+                       message_out = check_singlebyte_msg(esp, eregs, dregs);
+               } else if(esp->msgin_len == 2) {
+                       if(esp->cur_msgin[0] == EXTENDED_MESSAGE) {
+                               if((it+2) >= 15) {
+                                       message_out = MESSAGE_REJECT;
+                               } else {
+                                       esp->msgin_len = (it + 2);
+                                       esp_advance_phase(SCptr, in_msgincont);
+                               }
+                       } else {
+                               message_out = MESSAGE_REJECT; /* foo on you */
+                       }
+               } else {
+                       message_out = check_multibyte_msg(esp, eregs, dregs);
+               }
+       }
+       if(message_out < 0) {
+               return -message_out;
+       } else if(message_out) {
+               if(((message_out != 1) &&
+                   ((message_out < 0x20) || (message_out & 0x80))))
+                       esp->msgout_len = 1;
+               esp->cur_msgout[0] = message_out;
+               esp_cmd(esp, eregs, ESP_CMD_SATN);
+               esp_advance_phase(SCptr, in_the_dark);
+               esp->msgin_len = 0;
+       }
+       esp->sreg = eregs->esp_status;
+       esp->sreg &= ~(ESP_STAT_INTR);
+       if((esp->sreg & (ESP_STAT_PMSG|ESP_STAT_PCD)) == (ESP_STAT_PMSG|ESP_STAT_PCD))
+               esp_cmd(esp, eregs, ESP_CMD_MOK);
+       if((SCptr->SCp.sent_command == in_msgindone) &&
+           (SCptr->SCp.phase == in_freeing))
+               return esp_do_freebus(esp, eregs, dregs);
+       return do_intr_end;
+}
+
+static int esp_do_cmdbegin(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                          struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+
+       esp_advance_phase(SCptr, in_cmdend);
+       if(esp->erev == fashme) {
+               unsigned long tmp = dregs->cond_reg;
+               int i;
+
+               for(i = 0; i < esp->esp_scmdleft; i++)
+                       esp->esp_command[i] = *esp->esp_scmdp++;
+               esp->esp_scmdleft = 0;
+               esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+               esp_setcount(eregs, i, 1);
+               esp_cmd(esp, eregs, (ESP_CMD_DMA | ESP_CMD_TI));
+               tmp |= (DMA_SCSI_DISAB | DMA_ENABLE);
+               tmp &= ~(DMA_ST_WRITE);
+               dregs->cnt = i;
+               dregs->st_addr = esp->esp_command_dvma;
+               dregs->cond_reg = tmp;
+       } else {
+               unsigned char tmp;
+               esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+               tmp = *esp->esp_scmdp++;
+               esp->esp_scmdleft--;
+               eregs->esp_fdata = tmp;
+               esp_cmd(esp, eregs, ESP_CMD_TI);
+       }
+       return do_intr_end;
+}
+
+static int esp_do_cmddone(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                         struct sparc_dma_registers *dregs)
+{
+       if(esp->erev == fashme)
+               dma_invalidate(esp, dregs, dvmahme);
+       else
+               esp_cmd(esp, eregs, ESP_CMD_NULL);
+       if(esp->ireg & ESP_INTR_BSERV) {
+               esp_advance_phase(esp->current_SC, in_the_dark);
+               return esp_do_phase_determine(esp, eregs, dregs);
+       }
+       ESPLOG(("esp%d: in do_cmddone() but didn't get BSERV interrupt.\n",
+               esp->esp_id));
+       return do_reset_bus;
+}
+
+static int esp_do_msgout(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                        struct sparc_dma_registers *dregs)
+{
+       esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+       switch(esp->msgout_len) {
+       case 1:
+               if(esp->erev == fashme)
+                       hme_fifo_push(esp, eregs, &esp->cur_msgout[0], 1);
+               else
+                       eregs->esp_fdata = esp->cur_msgout[0];
+               esp_cmd(esp, eregs, ESP_CMD_TI);
+               break;
+
+       case 2:
+               esp->esp_command[0] = esp->cur_msgout[0];
+               esp->esp_command[1] = esp->cur_msgout[1];
+               if(esp->erev == fashme) {
+                       hme_fifo_push(esp, eregs, &esp->cur_msgout[0], 2);
+                       esp_cmd(esp, eregs, ESP_CMD_TI);
+               } else {
+                       dma_setup(dregs, esp->dma->revision,
+                                 esp->esp_command_dvma, 2, 0);
+                       esp_setcount(eregs, 2, 0);
+                       esp_cmd(esp, eregs, ESP_CMD_DMA | ESP_CMD_TI);
+               }
+               break;
+
+       case 4:
+               esp->esp_command[0] = esp->cur_msgout[0];
+               esp->esp_command[1] = esp->cur_msgout[1];
+               esp->esp_command[2] = esp->cur_msgout[2];
+               esp->esp_command[3] = esp->cur_msgout[3];
+               esp->snip = 1;
+               if(esp->erev == fashme) {
+                       hme_fifo_push(esp, eregs, &esp->cur_msgout[0], 4);
+                       esp_cmd(esp, eregs, ESP_CMD_TI);
+               } else {
+                       dma_setup(dregs, esp->dma->revision,
+                                 esp->esp_command_dvma, 4, 0);
+                       esp_setcount(eregs, 4, 0);
+                       esp_cmd(esp, eregs, ESP_CMD_DMA | ESP_CMD_TI);
+               }
+               break;
+
+       case 5:
+               esp->esp_command[0] = esp->cur_msgout[0];
+               esp->esp_command[1] = esp->cur_msgout[1];
+               esp->esp_command[2] = esp->cur_msgout[2];
+               esp->esp_command[3] = esp->cur_msgout[3];
+               esp->esp_command[4] = esp->cur_msgout[4];
+               esp->snip = 1;
+               if(esp->erev == fashme) {
+                       hme_fifo_push(esp, eregs, &esp->cur_msgout[0], 5);
+                       esp_cmd(esp, eregs, ESP_CMD_TI);
+               } else {
+                       dma_setup(dregs, esp->dma->revision,
+                                 esp->esp_command_dvma, 5, 0);
+                       esp_setcount(eregs, 5, 0);
+                       esp_cmd(esp, eregs, ESP_CMD_DMA | ESP_CMD_TI);
+               }
+               break;
+
+       default:
+               /* whoops */
+               ESPMISC(("bogus msgout sending NOP\n"));
+               esp->cur_msgout[0] = NOP;
+               if(esp->erev == fashme) {
+                       hme_fifo_push(esp, eregs, &esp->cur_msgout[0], 1);
+               } else {
+                       eregs->esp_fdata = esp->cur_msgout[0];
+               }
+               esp->msgout_len = 1;
+               esp_cmd(esp, eregs, ESP_CMD_TI);
+               break;
+       }
+       esp_advance_phase(esp->current_SC, in_msgoutdone);
+       return do_intr_end;
+}
+
+static int esp_do_msgoutdone(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                            struct sparc_dma_registers *dregs)
+{
+       if(esp->msgout_len > 1) {
+               /* XXX HME/FAS ATN deassert workaround required,
+                * XXX no DMA flushing, only possible ESP_CMD_FLUSH
+                * XXX to kill the fifo.
+                */
+               if(esp->erev != fashme) {
+                       while(dregs->cond_reg & DMA_PEND_READ)
+                               udelay(1);
+                       dregs->cond_reg &= ~(DMA_ENABLE);
+                       dma_invalidate(esp, dregs, esp->dma->revision);
+               } else {
+                       esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+               }
+       }
+       if(!(esp->ireg & ESP_INTR_DC)) {
+               if(esp->erev != fashme)
+                       esp_cmd(esp, eregs, ESP_CMD_NULL);
+               switch(esp->sreg & ESP_STAT_PMASK) {
+               case ESP_MOP:
+                       /* whoops, parity error */
+                       ESPLOG(("esp%d: still in msgout, parity error assumed\n",
+                               esp->esp_id));
+                       if(esp->msgout_len > 1)
+                               esp_cmd(esp, eregs, ESP_CMD_SATN);
+                       esp_advance_phase(esp->current_SC, in_msgout);
+                       return do_work_bus;
+
+               case ESP_DIP:
+                       break;
+
+               default:
+                       /* Happy Meal fifo is touchy... */
+                       if((esp->erev != fashme) &&
+                          !fcount(esp, eregs) &&
+                          !(esp->current_SC->device->sync_max_offset))
+                               esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+                       break;
+
+               };
+       } else {
+               ESPLOG(("esp%d: disconnect, resetting bus\n", esp->esp_id));
+               return do_reset_bus;
+       }
+
+       /* If we sent out a synchronous negotiation message, update
+        * our state.
+        */
+       if(esp->cur_msgout[2] == EXTENDED_MESSAGE &&
+          esp->cur_msgout[4] == EXTENDED_SDTR) {
+               esp->snip = 1; /* anal retentiveness... */
+       }
+
+       esp->prevmsgout = esp->cur_msgout[0];
+       esp->msgout_len = 0;
+       esp_advance_phase(esp->current_SC, in_the_dark);
+       return esp_do_phase_determine(esp, eregs, dregs);
+}
+
+static int esp_bus_unexpected(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+                             struct sparc_dma_registers *dregs)
+{
+       ESPLOG(("esp%d: command in weird state %2x\n",
+               esp->esp_id, esp->current_SC->SCp.phase));
+       return do_reset_bus;
+}
+
+static espfunc_t bus_vector[] = {
+       esp_do_data_finale,
+       esp_do_data_finale,
+       esp_bus_unexpected,
+       esp_do_msgin,
+       esp_do_msgincont,
+       esp_do_msgindone,
+       esp_do_msgout,
+       esp_do_msgoutdone,
+       esp_do_cmdbegin,
+       esp_do_cmddone,
+       esp_do_status,
+       esp_do_freebus,
+       esp_do_phase_determine,
+       esp_bus_unexpected,
+       esp_bus_unexpected,
+       esp_bus_unexpected,
+};
+
+/* This is the second tier in our dual-level SCSI state machine. */
+static int esp_work_bus(struct Sparc_ESP *esp,
+                       struct Sparc_ESP_regs *eregs,
+                       struct sparc_dma_registers *dregs)
+{
+       Scsi_Cmnd *SCptr = esp->current_SC;
+       unsigned int phase;
+
+       ESPBUS(("esp_work_bus: "));
+       if(!SCptr) {
+               ESPBUS(("reconnect\n"));
+               return esp_do_reconnect(esp, eregs, dregs);
+       }
+       phase = SCptr->SCp.phase;
+       if ((phase & 0xf0) == in_phases_mask)
+               return bus_vector[(phase & 0x0f)](esp, eregs, dregs);
+       else if((phase & 0xf0) == in_slct_mask)
+               return esp_select_complete(esp, eregs, dregs);
+       else
+               return esp_bus_unexpected(esp, eregs, dregs);
+}
+
+static espfunc_t isvc_vector[] = {
+       0,
+       esp_do_phase_determine,
+       esp_do_resetbus,
+       esp_finish_reset,
+       esp_work_bus
+};
+
+/* Main interrupt handler for an esp adapter. */
+static void esp_handle(struct Sparc_ESP *esp)
+{
+       struct sparc_dma_registers *dregs;
+       struct Sparc_ESP_regs *eregs;
+       Scsi_Cmnd *SCptr;
+       int what_next = do_intr_end;
+
+       eregs = esp->eregs;
+       dregs = esp->dregs;
+       SCptr = esp->current_SC;
+
+       /* Check for errors. */
+       esp->sreg = eregs->esp_status;
+       esp->sreg &= (~ESP_STAT_INTR);
+       if(esp->erev == fashme) {
+               esp->sreg2 = eregs->esp_status2;
+               esp->seqreg = (eregs->esp_sstep & ESP_STEP_VBITS);
+       }
+       if(esp->sreg & (ESP_STAT_SPAM)) {
+               /* Gross error, could be due to one of:
+                *
+                * - top of fifo overwritten, could be because
+                *   we tried to do a synchronous transfer with
+                *   an offset greater than ESP fifo size
+                *
+                * - top of command register overwritten
+                *
+                * - DMA setup to go in one direction, SCSI
+                *   bus points in the other, whoops
+                *
+                * - weird phase change during asynchronous
+                *   data phase while we are initiator
+                */
+               ESPLOG(("esp%d: Gross error sreg=%2x\n", esp->esp_id, esp->sreg));
+
+               /* If a command is live on the bus we cannot safely
+                * reset the bus, so we'll just let the pieces fall
+                * where they may.  Here we are hoping that the
+                * target will be able to cleanly go away soon
+                * so we can safely reset things.
+                */
+               if(!SCptr) {
+                       ESPLOG(("esp%d: No current cmd during gross error, "
+                               "resetting bus\n", esp->esp_id));
+                       what_next = do_reset_bus;
+                       goto state_machine;
+               }
+       }
+
+       if(dregs->cond_reg & DMA_HNDL_ERROR) {
+               /* A DMA gate array error.  Here we must
+                * be seeing one of two things.  Either the
+                * virtual to physical address translation
+                * on the SBUS could not occur, else the
+                * translation it did get pointed to a bogus
+                * page.  Ho hum...
+                */
+               ESPLOG(("esp%d: DMA error %08x\n", esp->esp_id,
+                       dregs->cond_reg));
+
+               /* DMA gate array itself must be reset to clear the
+                * error condition.
+                */
+               esp_reset_dma(esp);
+
+               what_next = do_reset_bus;
+               goto state_machine;
+       }
+
+       esp->ireg = eregs->esp_intrpt;   /* Unlatch intr and stat regs */
+
+       if(esp->erev == fashme) {
+               /* This chip is really losing. */
+               ESPHME(("HME["));
+
+               ESPHME(("sreg2=%02x,", esp->sreg2));
+               /* Must latch fifo before reading the interrupt
+                * register else garbage ends up in the FIFO
+                * which confuses the driver utterly.
+                */
+               if(!(esp->sreg2 & ESP_STAT2_FEMPTY) ||
+                  (esp->sreg2 & ESP_STAT2_F1BYTE)) {
+                       ESPHME(("fifo_workaround]"));
+                       hme_fifo_read(esp, eregs);
+               } else {
+                       ESPHME(("no_fifo_workaround]"));
+               }
+       }
+
+       /* No current cmd is only valid at this point when there are
+        * commands off the bus or we are trying a reset.
+        */
+       if(!SCptr && !esp->disconnected_SC && !(esp->ireg & ESP_INTR_SR)) {
+               /* Panic is safe, since current_SC is null. */
+               ESPLOG(("esp%d: no command in esp_handle()\n", esp->esp_id));
+               panic("esp_handle: current_SC == penguin within interrupt!");
+       }
+
+       if(esp->ireg & (ESP_INTR_IC)) {
+               /* Illegal command fed to ESP.  Outside of obvious
+                * software bugs that could cause this, there is
+                * a condition with esp100 where we can confuse the
+                * ESP into an erroneous illegal command interrupt
+                * because it does not scrape the FIFO properly
+                * for reselection.  See esp100_reconnect_hwbug()
+                * to see how we try very hard to avoid this.
+                */
+               ESPLOG(("esp%d: illegal command\n", esp->esp_id));
+
+               esp_dump_state(esp, eregs, dregs);
+
+               if(SCptr) {
+                       /* Devices with very buggy firmware can drop BSY
+                        * during a scatter list interrupt when using sync
+                        * mode transfers.  We continue the transfer as
+                        * expected, the target drops the bus, the ESP
+                        * gets confused, and we get a illegal command
+                        * interrupt because the bus is in the disconnected
+                        * state now and ESP_CMD_TI is only allowed when
+                        * a nexus is alive on the bus.
+                        */
+                       ESPLOG(("esp%d: Forcing async and disabling disconnect for "
+                               "target %d\n", esp->esp_id, SCptr->target));
+                       SCptr->device->borken = 1; /* foo on you */
+               }
+
+               what_next = do_reset_bus;
+       } else if(!(esp->ireg & ~(ESP_INTR_FDONE | ESP_INTR_BSERV | ESP_INTR_DC))) {
+               int phase;
+
+               if(SCptr) {
+                       phase = SCptr->SCp.phase;
+                       if(phase & in_phases_mask) {
+                               what_next = esp_work_bus(esp, eregs, dregs);
+                       } else if(phase & in_slct_mask) {
+                               what_next = esp_select_complete(esp, eregs, dregs);
+                       } else {
+                               ESPLOG(("esp%d: interrupt for no good reason...\n",
+                                       esp->esp_id));
+                               what_next = do_intr_end;
+                       }
+               } else {
+                       ESPLOG(("esp%d: BSERV or FDONE or DC while SCptr==NULL\n",
+                               esp->esp_id));
+                       what_next = do_reset_bus;
+               }
+       } else if(esp->ireg & ESP_INTR_SR) {
+               ESPLOG(("esp%d: SCSI bus reset interrupt\n", esp->esp_id));
+               what_next = do_reset_complete;
+       } else if(esp->ireg & (ESP_INTR_S | ESP_INTR_SATN)) {
+               ESPLOG(("esp%d: AIEEE we have been selected by another initiator!\n",
+                       esp->esp_id));
+               what_next = do_reset_bus;
+       } else if(esp->ireg & ESP_INTR_RSEL) {
+               if(!SCptr) {
+                       /* This is ok. */
+                       what_next = esp_do_reconnect(esp, eregs, dregs);
+               } else if(SCptr->SCp.phase & in_slct_mask) {
+                       /* Only selection code knows how to clean
+                        * up properly.
+                        */
+                       ESPDISC(("Reselected during selection attempt\n"));
+                       what_next = esp_select_complete(esp, eregs, dregs);
+               } else {
+                       ESPLOG(("esp%d: Reselected while bus is busy\n",
+                               esp->esp_id));
+                       what_next = do_reset_bus;
+               }
+       }
+
+       /* This is tier-one in our dual level SCSI state machine. */
+state_machine:
+       while(what_next != do_intr_end) {
+               if (what_next >= do_phase_determine &&
+                   what_next < do_intr_end)
+                       what_next = isvc_vector[what_next](esp, eregs, dregs);
+               else {
+                       /* state is completely lost ;-( */
+                       ESPLOG(("esp%d: interrupt engine loses state, resetting bus\n",
+                               esp->esp_id));
+                       what_next = do_reset_bus;
+               }
+       }
+}
+
+#ifndef __sparc_v9__
+
+#ifndef __SMP__
+static void esp_intr(int irq, void *dev_id, struct pt_regs *pregs)
+{
+       struct Sparc_ESP *esp;
+       unsigned long flags;
+       int again;
+
+       /* Handle all ESP interrupts showing at this IRQ level. */
+       spin_lock_irqsave(&io_request_lock, flags);
+repeat:
+       again = 0;
+       for_each_esp(esp) {
+               if((esp->irq & 0xf) == irq) {
+                       if(DMA_IRQ_P(esp->dregs)) {
+                               again = 1;
+
+                               DMA_INTSOFF(esp->dregs);
+
+                               ESPIRQ(("I%d(", esp->esp_id));
+                               esp_handle(esp);
+                               ESPIRQ((")"));
+
+                               DMA_INTSON(esp->dregs);
+                       }
+               }
+       }
+       if(again)
+               goto repeat;
+       spin_unlock_irqrestore(&io_request_lock, flags);
+}
+#else
+/* For SMP we only service one ESP on the list list at our IRQ level! */
+static void esp_intr(int irq, void *dev_id, struct pt_regs *pregs)
+{
+       struct Sparc_ESP *esp;
+       unsigned long flags;
+
+       /* Handle all ESP interrupts showing at this IRQ level. */
+       spin_lock_irqsave(&io_request_lock, flags);
+       for_each_esp(esp) {
+               if(((esp)->irq & 0xf) == irq) {
+                       if(DMA_IRQ_P(esp->dregs)) {
+                               DMA_INTSOFF(esp->dregs);
+
+                               ESPIRQ(("I[%d:%d](",
+                                       smp_processor_id(), esp->esp_id));
+                               esp_handle(esp);
+                               ESPIRQ((")"));
+
+                               DMA_INTSON(esp->dregs);
+                               goto out;
+                       }
+               }
+       }
+out:
+       spin_unlock_irqrestore(&io_request_lock, flags);
+}
+#endif
+
+static void esp_intr_4d(int irq, void *dev_id, struct pt_regs *pregs)
+{
+       struct Sparc_ESP *esp = dev_id;
+       unsigned long flags;
+
+       spin_lock_irqsave(&io_request_lock, flags);
+       if(DMA_IRQ_P(esp->dregs)) {
+               DMA_INTSOFF(esp->dregs);
+
+               ESPIRQ(("I[%d:%d](", smp_processor_id(), esp->esp_id));
+               esp_handle(esp);
+               ESPIRQ((")"));
+
+               DMA_INTSON(esp->dregs);
+       }
+       spin_unlock_irqrestore(&io_request_lock, flags);
+}
+
+#else /* __sparc_v9__ */
+
+static void esp_intr(int irq, void *dev_id, struct pt_regs *pregs)
+{
+       struct Sparc_ESP *esp = dev_id;
+       unsigned long flags;
+
+       spin_lock_irqsave(&io_request_lock, flags);
+       if(DMA_IRQ_P(esp->dregs)) {
+               DMA_INTSOFF(esp->dregs);
+
+               ESPIRQ(("I[%d:%d](", smp_processor_id(), esp->esp_id));
+               esp_handle(esp);
+               ESPIRQ((")"));
+
+               DMA_INTSON(esp->dregs);
+       }
+       spin_unlock_irqrestore(&io_request_lock, flags);
+}
+#endif
close