patch-2.1.16 linux/drivers/scsi/esp.c

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diff -u --recursive --new-file v2.1.15/linux/drivers/scsi/esp.c linux/drivers/scsi/esp.c
@@ -3,6 +3,15 @@
  * Copyright (C) 1995 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/kernel.h>
 #include <linux/delay.h>
 #include <linux/types.h>
@@ -19,39 +28,135 @@
 #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>
+#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) */
 
-#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__))
+#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
 
-/* This enum will be expanded when we have sync code written. */
+/* Command phase enumeration. */
 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     */
+	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           */
 };
 
 struct proc_dir_entry proc_scsi_esp = {
@@ -59,8 +164,11 @@
 	S_IFDIR | S_IRUGO | S_IXUGO, 2
 };
 
-struct Sparc_ESP *espchain;
+/* 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);
 static void esp_done(struct Sparc_ESP *esp, int error);
 
@@ -181,10 +289,102 @@
 		(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" :
+		   (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";
+	};
+}
+
+static inline void esp_advance_phase(Scsi_Cmnd *s, int newphase)
+{
+#ifdef DEBUG_STATE_MACHINE
+	ESPLOG(("<%s>", phase_string(newphase)));
+#endif
+	s->SCp.sent_command = s->SCp.phase;
+	s->SCp.phase = newphase;
+}
+
+extern inline void esp_cmd(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+			   unchar cmd)
+{
+#ifdef DEBUG_ESP_CMDS
+	esp->espcmdlog[esp->espcmdent] = cmd;
+	esp->espcmdent = (esp->espcmdent + 1) & 31;
+#endif
+	eregs->esp_cmd = cmd;
+}
+
+/* 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
@@ -207,6 +407,16 @@
 	restore_flags(flags);
 }
 
+static inline void prepend_SC(Scsi_Cmnd **SC, Scsi_Cmnd *new_SC)
+{
+	unsigned long flags;
+
+	save_flags(flags); cli();
+	new_SC->host_scribble = (unsigned char *) *SC;
+	*SC = new_SC;
+	restore_flags(flags);
+}
+
 static inline Scsi_Cmnd *remove_first_SC(Scsi_Cmnd **SC)
 {
 	Scsi_Cmnd *ptr;
@@ -240,58 +450,188 @@
 	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)
+/* Resetting various pieces of the ESP scsi driver chipset/buses. */
+static inline void esp_reset_dma(struct Sparc_ESP *esp)
 {
 	struct sparc_dma_registers *dregs = esp->dregs;
-	volatile unchar trash;
+	unsigned long tmp, flags;
+	int can_do_burst16, can_do_burst32;
+
+	can_do_burst16 = esp->bursts & DMA_BURST16;
+	can_do_burst32 = esp->bursts & DMA_BURST32;
 
 	/* 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->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 = 0x08000000;   /* Reset interface to FAS */
+		dregs->cond_reg = DMA_RST_SCSI; /* Reset DVMA itself */
+
+		tmp = (DMA_PARITY_OFF|DMA_2CLKS|DMA_SCSI_DISAB|DMA_INT_ENAB);
+		tmp &= ~(DMA_ENABLE|DMA_ST_WRITE|DMA_BRST_SZ);
+
+		if(can_do_burst32)
+			tmp |= DMA_BRST32;
+
+		/* This chip is horrible. */
+		while(dregs->cond_reg & DMA_PEND_READ)
+			udelay(1);
+
+		dregs->cond_reg = 0;
+
+		dregs->cond_reg = tmp;        /* bite me */
+		restore_flags(flags);         /* ugh...  */
+		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;
-	else if(esp->dma->revision == dvmarev3)
-		if(esp->erev == fas236 || esp->erev == fas100a) {
-			dregs->cond_reg &= ~(DMA_3CLKS);
-			dregs->cond_reg |= DMA_2CLKS;
+		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;
 		}
-	else if(esp->dma->revision == dvmaesc1)
+		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 inline 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 */
-	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... */
+	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_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_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;
+		printk("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->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)
+				esp->config3[i] |=
+					(ESP_CONFIG3_FCLOCK | ESP_CONFIG3_BIGID | ESP_CONFIG3_OBPUSH);
+			else
+				esp->config3[i] |= ESP_CONFIG3_FCLK;
+		}
+		eregs->esp_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;
-	if(esp->erev == esp236)
+		for(i=0; i<8; i++)
+			esp->config3[i] |= ESP_CONFIG3_FCLOCK;
 		eregs->esp_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 inline 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;
-	eregs->esp_cmd = ESP_CMD_RS;
-	do_pause(200);
+	esp_cmd(esp, eregs, ESP_CMD_RS);
+	udelay(400);
 	eregs->esp_cfg1 = esp->config1;
 
 	/* Eat any bitrot in the chip and we are done... */
@@ -312,34 +652,47 @@
 	struct Linux_SBus_DMA *dma, *dlink;
 	unsigned int fmhz;
 	unchar ccf, bsizes, bsizes_more;
-	int nesps = 0;
-	int esp_node;
+	int nesps = 0, esps_in_use = 0;
+	int esp_node, i;
 
 	espchain = 0;
 	if(!SBus_chain)
 		panic("No SBUS in esp_detect()");
 	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(!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? */
+				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? */
+				}
 			}
 			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 = nesps++;
 			/* Put into the chain of esp chips detected */
 			if(espchain) {
 				elink = espchain;
@@ -361,19 +714,31 @@
 			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;
+			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 we don't know how to handle the dvma,
+			 * do not use this device.
+			 */
 			if(!dlink){
-				printk ("Cannot find dvma for ESP SCSI\n");
+				printk ("Cannot find dvma for ESP%d's SCSI\n",
+					esp->esp_id);
 				scsi_unregister (esp_host);
 				continue;
 			}
 			if (dlink->allocated){
-				printk ("esp: can't use my espdma\n");
+				printk ("esp%d: can't use my espdma\n",
+					esp->esp_id);
 				scsi_unregister (esp_host);
 				continue;
 			}
@@ -383,11 +748,23 @@
 			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 *)
+			if(!hme) {
+				prom_apply_sbus_ranges(esp->edev->my_bus, 
+						       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);
+			} 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 =
@@ -400,7 +777,6 @@
 			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 */
@@ -409,41 +785,102 @@
 					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,
+			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 ", nesps, esp->ehost->irq);
+			printk("esp%d: IRQ %d ", esp->esp_id, esp->ehost->irq);
+
 			/* Figure out our scsi ID on the bus */
 			esp->scsi_id = prom_getintdefault(esp->prom_node,
-							  "initiator-id", -1);
+							  "initiator-id",
+							  -1);
 			if(esp->scsi_id == -1)
 				esp->scsi_id = prom_getintdefault(esp->prom_node,
-								  "scsi-initiator-id", -1);
+								  "scsi-initiator-id",
+								  -1);
 			if(esp->scsi_id == -1)
 				esp->scsi_id =
 					prom_getintdefault(esp->edev->my_bus->prom_node,
-							   "scsi-initiator-id", 7);
+							   "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);
+
+			/* 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 = prom_getintdefault(esp->edev->my_bus->prom_node,
-							  "clock-frequency", -1);
-			if(fmhz <= (5000))
+							  "clock-frequency",
+							  -1);
+			if(fmhz <= (5000000))
 				ccf = 0;
 			else
-				ccf = (((5000 - 1) + (fmhz))/(5000));
+				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 = (5000 * 4);
+				fmhz = (20000000);
 			}
 			if(ccf==(ESP_CCF_F7+1))
 				esp->cfact = ESP_CCF_F0;
@@ -452,31 +889,38 @@
 			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);
+			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  Clock %d MHz CCF=%d Time-Out %d ",
+			       esp->scsi_id, (fmhz / 1000000),
+			       ccf, (int) esp->neg_defp);
 
-			/* Find the burst sizes this dma supports. */
+			/* 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;
+			}
 			bsizes_more = prom_getintdefault(esp->edev->my_bus->prom_node,
 							 "burst-sizes", 0xff);
-			if(bsizes_more != 0xff) bsizes &= bsizes_more;
+			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)) {
@@ -495,11 +939,11 @@
 					for(target=0; target<8; target++)
 						esp->config3[target] = 0;
 					eregs->esp_cfg3 = 0;
-					if(esp->cfact > ESP_CCF_F5) {
+					if(ccf > ESP_CCF_F5) {
 						printk("NCR53C9XF(espfast) detected\n");
 						esp->erev = fast;
-						esp->config2 |= ESP_CONFIG2_FENAB;
-						eregs->esp_cfg2 = esp->config2;
+						eregs->esp_cfg2 = esp->config2 = 0;
+						esp->sync_defp = SYNC_DEFP_FAST;
 					} else {
 						printk("NCR53C9x(esp236) detected\n");
 						esp->erev = esp236;
@@ -513,20 +957,34 @@
 			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;
+
 			/* 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
+			esps_in_use++;
 		} /* for each sbusdev */
 	} /* for each sbus */
-	return nesps;
+	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;
 }
 
-/*
- * The info function will return whatever useful
+/* The info function will return whatever useful
  * information the developer sees fit.  If not provided, then
  * the name field will be used instead.
  */
@@ -542,10 +1000,10 @@
 		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 fashme:
+		return "Sparc ESP366-HME";
 	case fas100a:
 		return "Sparc ESP100A-FAST";
 	default:
@@ -553,142 +1011,710 @@
 	};
 }
 
-/* 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)
+/* From Wolfgang Stanglmeier's NCR scsi driver. */
+struct info_str
 {
-	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);
+	char *buffer;
+	int length;
+	int offset;
+	int pos;
+};
 
-	eregs->esp_tclow = 0;
-	eregs->esp_tcmed = 0;
-	eregs->esp_cmd   = (ESP_CMD_NULL | ESP_CMD_DMA);
+static void copy_mem_info(struct info_str *info, char *data, int len)
+{
+	if (info->pos + len > info->length)
+		len = info->length - info->pos;
 
-	/* Flush the fifo of excess garbage. */
-	eregs->esp_cmd   = ESP_CMD_FLUSH;
+	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);
+	}
 
-	/* Load bus-id and timeout values. */
-	eregs->esp_busid = (SCptr->target & 7);
-	eregs->esp_timeo = esp->sync_defp;
+	if (len > 0) {
+		memcpy(info->buffer + info->pos, data, len);
+		info->pos += len;
+	}
+}
 
-	eregs->esp_soff  = 0; /* This means async transfer... */
-	eregs->esp_stp   = 0;
+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);
 
-	/* Load FIFO with the actual SCSI command. */
-	for(i=0; i < SCptr->cmd_len; i++)
-		eregs->esp_fdata = SCptr->cmnd[i];
+	copy_mem_info(info, buf, len);
+	return len;
+}
 
-	/* Make sure the dvma forwards the ESP interrupt. */
-	dregs->cond_reg = DMA_INT_ENAB;
+static int esp_host_info(struct Sparc_ESP *esp, char *ptr, off_t offset, int len)
+{
+	struct info_str info;
+	int i;
 
-	/* Tell ESP to SELECT without asserting ATN. */
-	eregs->esp_cmd = ESP_CMD_SEL;
-	return;
+	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 = scsi_devices;
+
+			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");
+		}
+	}
 
-bad:
-	panic("esp: daaarrrkk starrr crashesss....");
+	return info.pos > info.offset? info.pos - info.offset : 0;
 }
 
-/* Queue a SCSI command delivered from the mid-level Linux SCSI code. */
-int esp_queue(Scsi_Cmnd *SCpnt, void (*done)(Scsi_Cmnd *))
+/* 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;
-	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;
+	if(inout)
+		return -EINVAL; /* not yet */
 
-	/* 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;
+	for_each_esp(esp) {
+		if(esp->ehost->host_no == hostno)
+			break;
 	}
+	if(!esp)
+		return -EINVAL;
 
-	/* Place into our queue. */
-	append_SC(&esp->issue_SC, SCpnt);
-
-	/* Run it now if we can */
-	if(!esp->current_SC)
-		esp_exec_cmd(esp);
+	if(start)
+		*start = buffer;
 
-	restore_flags(flags);
-	return 0;
+	return esp_host_info(esp, buffer, offset, length);
 }
 
-/* Only queuing supported in this ESP driver. */
-int esp_command(Scsi_Cmnd *SCpnt)
+/* 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)
 {
-	ESPLOG(("esp: esp_command() called...\n"));
+	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 inline 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've been reselected. */
+	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 {
+		int toshiba_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.. lets 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 ||
+			    strncmp(SDptr->vendor, "TOSHIBA", 7))) {
+				build_wide_nego_msg(esp, 16);
+				esp->config3[SCptr->target] |= ESP_CONFIG3_EWIDE;
+				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) &&
+			   (!strncmp(SDptr->vendor, "TOSHIBA", 7))) {
+				/* Nice try sucker... */
+				printk(KERN_INFO "esp%d: Disabling sync for buggy "
+				       "Toshiba CDROM.\n", esp->esp_id);
+				toshiba_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)) ||
+#if 1 /* Until I find out why HME barfs with disconnects enabled... */
+		   toshiba_cdrom_hwbug_wkaround || SDptr->borken || esp->erev == fashme) {
+#else
+		   toshiba_cdrom_hwbug_wkaround || SDptr->borken) {
+#endif
+			printk(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);
+	eregs->esp_soff = SDptr->sync_max_offset;
+	eregs->esp_stp  = SDptr->sync_min_period;
+	if(esp->erev > esp100a)
+		eregs->esp_cfg3 = esp->config3[target];
+
+	i = (cmdp - esp->esp_command);
+
+	if(esp->erev == fashme) {
+		unsigned long tmp;
+
+		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... */
+		tmp = dregs->cond_reg;
+		tmp |= (DMA_SCSI_DISAB | DMA_ENABLE);
+		tmp &= ~(DMA_ST_WRITE);
+		dregs->cnt = 16;
+		dregs->st_addr = esp->esp_command;
+		dregs->cond_reg = tmp;
+	} 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;
+
+		/* 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;
+	unsigned long flags;
+	int don;
+
+	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;
+	dregs = esp->dregs;
+
+	don = (dregs->cond_reg & DMA_INT_ENAB);
+	if(don)
+		DMA_INTSOFF(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));
+	if(!SCpnt->use_sg) {
+		ESPQUEUE(("!use_sg\n"));
+		SCpnt->SCp.this_residual    = SCpnt->request_bufflen;
+		SCpnt->SCp.buffer           =
+			(struct scatterlist *) SCpnt->request_buffer;
+		SCpnt->SCp.buffers_residual = 0;
+		/* Sneaky. */
+		SCpnt->SCp.have_data_in = (int) SCpnt->SCp.ptr =
+			mmu_get_scsi_one((char *)SCpnt->SCp.buffer,
+					 SCpnt->SCp.this_residual,
+					 esp->edev->my_bus);
+	} else {
+		ESPQUEUE(("use_sg "));
+#ifdef DEBUG_ESP_SG
+		printk("esp%d: sglist at %p with %d buffers\n",
+		       esp->esp_id, 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->dvma_address;
+	}
+	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);
+
+	if(don)
+		DMA_INTSON(dregs);
+	restore_flags(flags);
+	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;
 }
 
-/* Abort a command.  Those that are on the bus force a SCSI bus
- * reset.
- */
-int esp_abort(Scsi_Cmnd *SCpnt)
+/* Dump driver state. */
+static inline 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 inline 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<%08lx> addr<%p>\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)
 {
-	ESPLOG(("esp_abort: Not implemented yet\n"));
-	return SCSI_ABORT_ERROR;
+	struct Sparc_ESP *esp = (struct Sparc_ESP *) SCptr->host->hostdata;
+	struct Sparc_ESP_regs *eregs = esp->eregs;
+	struct sparc_dma_registers *dregs = esp->dregs;
+	unsigned long flags;
+	int don;
+
+	ESPLOG(("esp%d: Aborting command\n", esp->esp_id));
+	save_flags(flags); cli();
+
+	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);
+		restore_flags(flags);
+		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);
+	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;
+				this->result = DID_ABORT << 16;
+				this->done(this);
+				cli();
+				if(don)
+					DMA_INTSON(dregs);
+				restore_flags(flags);
+				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);
+		restore_flags(flags);
+		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 bug.
+	 */
+
+	if(don)
+		DMA_INTSON(dregs);
+	restore_flags(flags);
+	return SCSI_ABORT_SNOOZE;
 }
 
 /* Reset ESP chip, reset hanging bus, then kill active and
@@ -696,8 +1722,13 @@
  */
 int esp_reset(Scsi_Cmnd *SCptr, unsigned int how)
 {
-	ESPLOG(("esp_reset: Not implemented yet\n"));
-	return SCSI_RESET_ERROR;
+	struct Sparc_ESP *esp = (struct Sparc_ESP *) SCptr->host->hostdata;
+	struct Sparc_ESP_regs *eregs = esp->eregs;
+
+	ESPLOG(("esp%d: Resetting scsi bus\n", esp->esp_id));
+	esp->resetting_bus = 1;
+	esp_cmd(esp, eregs, ESP_CMD_RS);
+	return SCSI_RESET_PENDING;
 }
 
 /* Internal ESP done function. */
@@ -709,17 +1740,20 @@
 	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);
+			/* Sneaky. */
+			mmu_release_scsi_one((char *)done_SC->SCp.have_data_in,
+					     done_SC->request_bufflen,
+					     esp->edev->my_bus);
 		} else {
 			struct scatterlist *scl = (struct scatterlist *)done_SC->buffer;
 #ifdef DEBUG_ESP_SG
-			printk("esp: unmapping sg ");
+			printk("esp%d: unmapping sg ", esp->esp_id);
 #endif
 			mmu_release_scsi_sgl((struct mmu_sglist *) scl,
 					     done_SC->use_sg - 1,
@@ -728,387 +1762,2292 @@
 			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");
 
+		/* There is a window of time within the scsi_done() path
+		 * of execution where interrupts are turned back on full
+		 * blast and left that way.  During that time we could
+		 * reconnect to a disconnected command, then we'd bomb
+		 * out below.  We could also end up executing two commands
+		 * at _once_.  ...just so you know why the cli() is here...
+		 */
+
+		cli(); /* GRRR!!! */
+
 		/* Bus is free, issue any commands in the queue. */
-		if(esp->issue_SC)
+		if(esp->issue_SC && !esp->current_SC)
 			esp_exec_cmd(esp);
 
 		restore_flags(flags);
 		/* End of critical section... */
-	} else
+	} 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");
+	}
 }
 
-#ifdef THREADED_ESP_DRIVER /* planning stage... */
+/* Wheee, ESP interrupt engine. */  
 
-/* 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...
- */
+enum {
+	do_phase_determine, do_reset_bus, do_reset_complete,
+	do_work_bus, do_intr_end,
+};
+
+/* 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);
 
-static void esp_kernel_thread(void *opaque)
+static inline int sreg_datainp(unchar sreg)
 {
-	struct Sparc_ESP *esp = opaque;
+	return (sreg & ESP_STAT_PMASK) == ESP_DIP;
+}
 
-	for(;;) {
-		unsigned long flags;
+static inline int sreg_dataoutp(unchar sreg)
+{
+	return (sreg & ESP_STAT_PMASK) == ESP_DOP;
+}
 
-		while(esp->eatme_SC) {
-			struct Scsi_Cmnd *SCpnt;
+/* Did they drop these fabs on the floor or what?!?!! */
+static inline void hme_fifo_hwbug_workaround(struct Sparc_ESP *esp,
+					     struct Sparc_ESP_regs *eregs)
+{
+	unchar status = esp->sreg;
+
+	/* Cannot safely frob the fifo for these following cases. */
+	if(sreg_datainp(status) || sreg_dataoutp(status) ||
+	   (esp->current_SC && esp->current_SC->SCp.phase == in_data_done)) {
+		ESPHME(("<wkaround_skipped>"));
+		return;
+	} else {
+		unsigned long count = 0;
+		unsigned long fcnt = eregs->esp_fflags & ESP_FF_FBYTES;
 
-			SCpnt = remove_first_SC(esp->eatme_SC);
-			esp_done(esp, error, SCpnt);
+		/* 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"));
 		}
-		sleep();
+		esp->hme_fifo_workaround_count = count;
+		ESPHME(("wkarnd_cnt=%d]", (int)count));
 	}
 }
-#endif
 
-/* Read the interrupt status registers on this ESP board */
-static inline void esp_updatesoft(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
+static inline void hme_fifo_push(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+				 unchar *bytes, unchar count)
 {
-	/* 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_cmd(esp, eregs, ESP_CMD_FLUSH);
+	while(count) {
+		eregs->esp_fdata = *bytes++;
+		eregs->esp_fdata = 0;
+		count--;
+	}
+}
 
-	esp->seqreg = eregs->esp_sstep;
-	esp->sreg = eregs->esp_status;
+/* 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. */
+		esp->sreg = eregs->esp_status;
+		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]"));
+			hme_fifo_hwbug_workaround(esp, eregs);
+		}
+		esp->ireg = eregs->esp_intrpt;
+		esp->sreg &= ~(ESP_STAT_INTR);
+		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;
+}
 
-	/* 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 */
+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. */
+		esp->sreg = eregs->esp_status;
+		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]"));
+			hme_fifo_hwbug_workaround(esp, eregs);
+		}
+		esp->ireg = eregs->esp_intrpt;
+		esp->sreg &= ~(ESP_STAT_INTR);
+		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;
 }
 
-/* #define ESP_IRQ_TRACE */
+/* Now some dma helpers. */
+static inline void dma_setup(struct sparc_dma_registers *dregs, enum dvma_rev drev,
+			     char *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! */
+		unsigned long src = ((unsigned long) addr);
+		unsigned long dest = src + count;
+
+		if(dest & (PAGE_SIZE - 1))
+			count = PAGE_ALIGN(count);
+		dregs->cnt = count;
+	}
+	dregs->st_addr = addr;
+}
 
-#ifdef ESP_IRQ_TRACE
-#define ETRACE(foo)  printk foo
-#else
-#define ETRACE(foo)
-#endif
+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;
 
-static char last_fflags, last_status, last_msg;
+		case dvmarev3:
+		case dvmaesc1:
+			while(dregs->cond_reg & DMA_FIFO_ISDRAIN)
+				udelay(1);
+		};
+	}
+}
 
-/* Main interrupt handler for an esp adapter. */
-static inline void esp_handle(struct Sparc_ESP *esp)
+static inline void dma_invalidate(struct sparc_dma_registers *dregs, enum dvma_rev drev)
 {
-	struct sparc_dma_registers *dregs;
-	struct Sparc_ESP_regs *eregs;
-	Scsi_Cmnd *SCptr;
+	unsigned long tmp;
 
-	eregs = esp->eregs;
-	dregs = esp->dregs;
-	SCptr = esp->current_SC;
+	if(drev == dvmahme) {
+		/* SMCC can bite me. */
+		tmp = dregs->cond_reg;
+		dregs->cond_reg = DMA_RST_SCSI;
+		tmp |= (DMA_PARITY_OFF|DMA_2CLKS|DMA_SCSI_DISAB|DMA_INT_ENAB);
+		tmp &= ~(DMA_ENABLE|DMA_ST_WRITE);
+		dregs->cond_reg = 0;
+		dregs->cond_reg = tmp;
+	} else {
+		while(dregs->cond_reg & DMA_PEND_READ)
+			udelay(1);
 
-	DMA_IRQ_ENTRY(esp->dma, dregs);
-	esp_updatesoft(esp, eregs);
+		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));
+	}
+}
 
-	ETRACE(("ESPIRQ: <%2x,%2x,%2x> --> ", esp->ireg, esp->sreg, esp->seqreg));
+static inline void dma_flashclear(struct sparc_dma_registers *dregs, enum dvma_rev drev)
+{
+	dma_drain(dregs, drev);
+	dma_invalidate(dregs, drev);
+}
 
-	/* Check for errors. */
-	if(!SCptr)
-		panic("esp_handle: current_SC == penguin within interrupt!");
+static inline int dma_can_transfer(Scsi_Cmnd *sp, enum dvma_rev drev)
+{
+	unsigned long base, end, sz;
 
-	/* 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(drev == dvmarev3) {
+		sz = sp->SCp.this_residual;
+		if(sz > 0x1000000)
+			sz = 0x1000000;
+	} else {
+		base = (unsigned long) sp->SCp.ptr;
+		base &= (0x1000000 - 1);
+		end = (base + sp->SCp.this_residual);
+		if(end > 0x1000000)
+			end = 0x1000000;
+		sz = (end - base);
 	}
-	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");
+	return sz;
+}
+
+/* Misc. esp helper routines. */
+static inline void esp_setcount(struct Sparc_ESP_regs *eregs, int cnt, int hme)
+{
+	eregs->esp_tclow = (cnt & 0xff);
+	eregs->esp_tcmed = ((cnt >> 8) & 0xff);
+	if(hme) {
+		eregs->fas_rlo = 0;
+		eregs->fas_rhi = 0;
 	}
+}
 
-	/* 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;
+static inline int esp_getcount(struct Sparc_ESP_regs *eregs)
+{
+	return (((eregs->esp_tclow)&0xff) |
+		(((eregs->esp_tcmed)&0xff) << 8));
+}
 
-				/* 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!");
+static inline int fcount(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
+{
+	if(esp->erev == fashme)
+		return esp->hme_fifo_workaround_count;
+	else
+		return eregs->esp_fflags & ESP_FF_FBYTES;
+}
 
-	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;
+static inline int fnzero(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
+{
+	if(esp->erev == fashme)
+		return 0;
+	else
+		return eregs->esp_fflags & ESP_FF_ONOTZERO;
+}
 
-			/* fall through */
-		case dvmaesc1:
-			/* Wait for the fifo to drain completely. */
-			while(dregs->cond_reg & DMA_FIFO_ISDRAIN)
-				barrier();
+/* 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...
+ */
+static inline void esp_maybe_nop(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs)
+{
+	if(esp->erev == esp100)
+		esp_cmd(esp, eregs, ESP_CMD_NULL);
+}
+
+static inline int sreg_to_dataphase(unchar sreg)
+{
+	if((sreg & ESP_STAT_PMASK) == ESP_DOP)
+		return in_dataout;
+	else
+		return 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;
+	if(esp->sreg & ESP_STAT_PERR)
+		return 0;
+	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;
+	eregs->esp_soff = dp->sync_max_offset;
+	eregs->esp_stp  = dp->sync_min_period;
+	if(esp->erev > esp100a)
+		eregs->esp_cfg3 = esp->config3[sp->target];
+	if(esp->erev == fashme)
+		eregs->esp_busid = (sp->target & 0xf) |
+			(ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT);
+	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)
+		printk("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 inline 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 = (((unsigned long)dregs->st_addr) -
+		    ((unsigned long)esp->esp_command));
+
+	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 = sp->SCp.buffer->dvma_address;
+}
+
+/* Complete a command, this is the only way to safely finish
+ * a command with disconnected commands or a reset interrupt
+ * pending because scsi_done() can enable interrupts full blast.
+ */
+static inline void safe_esp_done(struct Sparc_ESP *esp,
+				 struct sparc_dma_registers *dregs,
+				 int error)
+{
+	int before = 0;
+
+	if(dregs->cond_reg & DMA_INT_ENAB) {
+		before = 1;
+		DMA_INTSOFF(dregs);
+	}
+	esp_done(esp, error);
+	if(before)
+		DMA_INTSON(dregs);
+}
+
+/* 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 inline 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 = dregs->cond_reg;
+
+		/* Touchy chip, this stupid HME scsi adapter... */
+		esp_setcount(eregs, hmuch, 1);
+		esp_cmd(esp, eregs, ESP_CMD_DMA | ESP_CMD_TI);
+		dregs->cnt = hmuch;
+		tmp |= (DMA_SCSI_DISAB | DMA_ENABLE);
+		if(thisphase == in_datain)
+			tmp |= DMA_ST_WRITE;
+		else
+			tmp &= ~(DMA_ST_WRITE);
+		dregs->st_addr = SCptr->SCp.ptr;
+		dregs->cond_reg = tmp;
+	} else {
+		esp_setcount(eregs, hmuch, 0);
+		dma_setup(dregs, esp->dma->revision, 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 inline 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(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;
+
+	/* Uhhh, might not want both of these conditionals to run
+	 * at once on HME due to the fifo problems it has.  Consider
+	 * changing it to:
+	 *
+	 * 	if(!(esp->sreg & ESP_STAT_TCNT)) {
+	 * 		bytes_sent -= ecount;
+	 * 	} else if(SCptr->SCp.phase == in_dataout) {
+	 * 		bytes_sent -= fifocnt;
+	 *	}
+	 *
+	 * But only for the HME case, leave the current code alone
+	 * for all other ESP revisions as we know the existing code
+	 * works just fine for them.
+	 */
+	ESPDATA(("trans_sz=%d, ", bytes_sent));
+	if(esp->erev == fashme) {
+		if(!(esp->sreg & ESP_STAT_TCNT)) {
+			bytes_sent -= esp_getcount(eregs);
+		} else if(SCptr->SCp.phase == in_dataout) {
+			bytes_sent -= fifocnt;
+		}
+	} 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.
+		 */
+		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));
+		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 */
+		printk("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;
+}
+
+/* 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 inline 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(SCptr->cmnd[0] != START_STOP &&
+			   SCptr->data_cmnd[0] != START_STOP &&
+			   SCptr->cmnd[0] != TEST_UNIT_READY &&
+			   SCptr->data_cmnd[0] != TEST_UNIT_READY &&
+			   !(SCptr->device->type == TYPE_TAPE &&
+			     (SCptr->cmnd[0] == TEST_UNIT_READY ||
+			      SCptr->data_cmnd[0] == TEST_UNIT_READY ||
+			      SCptr->cmnd[0] == MODE_SENSE ||
+			      SCptr->data_cmnd[0] == MODE_SENSE)))
+				SCptr->device->sync = 0;
+		}
+		ESPDISC(("F<%02x,%02x>", SCptr->target, SCptr->lun));
+		safe_esp_done(esp, dregs, ((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;
+}
+
+/* Do the needy when a target tries to reconnect to us. */
+static inline 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 flush both FIFO and the DVMA on HME. */
+	if(esp->erev == fashme) {
+		/* XXX this still doesn't fix the problem... */
+		esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+		dma_invalidate(esp->dregs, dvmahme);
+	} else {
+		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) {
+		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;
+	}
+	esp_connect(esp, eregs, SCptr);
+	esp_cmd(esp, eregs, ESP_CMD_MOK);
+
+	/* No need for explicit restore pointers operation. */
+	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(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);
+	}
+}
+
+/* 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)
+{
+	Scsi_Cmnd *SCptr = esp->current_SC;
+
+	ESPPHASE(("esp_do_phase_determine: "));
+	if(!(esp->ireg & ESP_INTR_DC)) {
+		switch(esp->sreg & ESP_STAT_PMASK) {
+		case ESP_DOP:
+		case ESP_DIP:
+			ESPPHASE(("to data phase\n"));
+			return esp_do_data(esp, eregs, dregs);
+
+		case ESP_STATP:
+			/* Whee, status phase, finish up the command. */
+			ESPPHASE(("to status phase\n"));
+			esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+			if(esp->erev != fashme) {
+				esp->esp_command[0] = 0xff;
+				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 = 0x1000;
+				dregs->st_addr = esp->esp_command;
+				esp_cmd(esp, eregs, ESP_CMD_DMA | ESP_CMD_ICCSEQ);
+			} else {
+				/* Using DVMA for status/message bytes is
+				 * unreliable on HME, nice job QLogic.
+				 * Happy Meal indeed....
+				 */
+				esp_cmd(esp, eregs, ESP_CMD_ICCSEQ);
+			}
+			esp_advance_phase(SCptr, in_status);
+			return esp_do_status(esp, eregs, dregs);
+
+		case ESP_MOP:
+			ESPPHASE(("to msgout phase\n"));
+			esp_advance_phase(SCptr, in_msgout);
+			return esp_do_msgout(esp, eregs, dregs);
+
+		case ESP_MIP:
+			ESPPHASE(("to msgin phase\n"));
+			esp_advance_phase(SCptr, in_msgin);
+			return esp_do_msgin(esp, eregs, dregs);
+
+		case ESP_CMDP:
+			/* Ugh, we're running a non-standard command the
+			 * ESP doesn't understand, one byte at a time.
+			 */
+			ESPPHASE(("to cmd phase\n"));
+			esp_advance_phase(SCptr, in_cmdbegin);
+			return esp_do_cmdbegin(esp, eregs, dregs);
+		};
+	} else {
+		Scsi_Device *dp = SCptr->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(SCptr->SCp.phase),
+			phase_string(SCptr->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(SCptr, in_tgterror);
+			safe_esp_done(esp, dregs, (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(SCptr, in_resetdev);
+			safe_esp_done(esp, dregs, (DID_RESET << 16));
 			break;
+
+		case ABORT:
+			ESPLOG(("device abort successful\n"));
+			esp_advance_phase(SCptr, in_abortone);
+			safe_esp_done(esp, dregs, (DID_ABORT << 16));
+			break;
+
 		};
+		return do_intr_end;
+	}
 
-	case in_dataout:
-		dregs->cond_reg &= ~DMA_ENABLE;
+	ESPLOG(("esp%d: to unknown phase\n", esp->esp_id));
+	printk("esp%d: Bizarre bus phase %2x.\n", esp->esp_id,
+	       esp->sreg & ESP_STAT_PMASK);
+	return do_reset_bus;
+}
+
+/* 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(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);
+	}
 
-		/* 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.
+	/* 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...
 				 */
-				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;
+				esp->esp_slowcmd = 1;
+				esp->esp_scmdp = &(SCptr->cmnd[cmd_bytes_sent]);
+				esp->esp_scmdleft = (SCptr->cmd_len - cmd_bytes_sent);
+			}
+		}
 
-#ifdef DEBUG_ESP_SG
-				printk("<%p,%d> ", SCptr->SCp.ptr,
-				       SCptr->SCp.this_residual);
-#endif
+		/* 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;
+			printk("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 dont 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;
+		}
 
-				/* 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;
+		/* 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)) {
+			printk("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.
+			 */
+			safe_esp_done(esp, dregs, (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));
+			safe_esp_done(esp, dregs, (DID_BAD_TARGET << 16));
+		}
+		return do_intr_end;
+	}
 
-				/* Tell the esp to start transferring. */
-				eregs->esp_cmd = (ESP_CMD_DMA | ESP_CMD_TI);
-				goto esp_handle_done;
+
+	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.
+		 */
+		printk("esp%d: message in mis-carriage.\n", esp->esp_id);
+	}
+	esp_advance_phase(esp->current_SC, in_the_dark);
+	return do_phase_determine;
+}
+
+static inline 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 dont 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:
+	case SAVE_POINTERS:
+		/* We handle this all automatically. */
+		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 inline 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 inline 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";
+		}
+		printk(KERN_INFO "esp%d: target %d [period %dns offset %d %d.%02dMHz %s SCSI%s]\n",
+		       esp->esp_id, esp->current_SC->target,
+		       (int) msg3 * 4,
+		       (int) msg4,
+		       integer, fraction, type,
+		       (((msg3 * 4) < 200) ? "-II" : ""));
+	} else {
+		printk(KERN_INFO "esp%d: target %d asynchronous\n",
+		       esp->esp_id, esp->current_SC->target);
+	}
+}
+
+static inline 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--;
 			}
-#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;
+
+		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->config3[SCptr->target];
 			}
-			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;
+			eregs->esp_soff = SDptr->sync_min_period;
+			eregs->esp_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 = 0;
+			eregs->esp_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->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) {
+			printk("esp%d: AIEEE wide msg received and not HME.\n",
+			       esp->esp_id);
+			message_out = MESSAGE_REJECT;
+		} else if(size > 16) {
+			printk("esp%d: AIEEE wide transfer for %d size not supported.\n",
+			       esp->esp_id, size);
+			message_out = MESSAGE_REJECT;
+		} else {
+			/* Things look good, lets see what we got. */
+			if(size == 16) {
+				/* Set config 3 register for this target. */
+				printk("esp%d: 16 byte WIDE transfers enabled for target %d.\n",
+				       esp->esp_id, SCptr->target);
+				esp->config3[SCptr->target] |= ESP_CONFIG3_EWIDE;
+			} else {
+				/* Just make sure it was one byte sized. */
+				if(size != 8) {
+					printk("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->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[0];
+		dregs->cond_reg = tmp;
+	} else {
+		esp_cmd(esp, eregs, ESP_CMD_FLUSH);
+		eregs->esp_fdata = *esp->esp_scmdp++;
+		esp->esp_scmdleft--;
+		esp_cmd(esp, eregs, ESP_CMD_TI);
+	}
+	return do_intr_end;
+}
+
+static inline int esp_do_cmddone(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+				 struct sparc_dma_registers *dregs)
+{
+	if(esp->erev == fashme)
+		dma_invalidate(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,
+				  (char *) esp->esp_command, 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,
+				  (char *) esp->esp_command, 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,
+				  (char *) esp->esp_command, 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 inline 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(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);
+}
+
+/* This is the second tier in our dual-level SCSI state machine. */
+static inline int esp_work_bus(struct Sparc_ESP *esp, struct Sparc_ESP_regs *eregs,
+			       struct sparc_dma_registers *dregs)
+{
+	Scsi_Cmnd *SCptr = esp->current_SC;
+
+	ESPBUS(("esp_work_bus: "));
+	if(!SCptr) {
+		ESPBUS(("reconnect\n"));
+		return esp_do_reconnect(esp, eregs, dregs);
+	}
+
+	switch(SCptr->SCp.phase) {
+	case in_the_dark:
+		ESPBUS(("in the dark\n"));
+		return esp_do_phase_determine(esp, eregs, dregs);
+
+	case in_slct_norm:
+	case in_slct_stop:
+	case in_slct_msg:
+	case in_slct_tag:
+	case in_slct_sneg:
+		ESPBUS(("finish selection\n"));
+		return esp_select_complete(esp, eregs, dregs);
+
+	case in_datain:
+	case in_dataout:
+		ESPBUS(("finish data\n"));
+		return esp_do_data_finale(esp, eregs, dregs);
+
+	case in_msgout:
+		ESPBUS(("message out "));
+		return esp_do_msgout(esp, eregs, dregs);
+
+	case in_msgoutdone:
+		ESPBUS(("finish message out "));
+		return esp_do_msgoutdone(esp, eregs, dregs);
+
+	case in_msgin:
+		ESPBUS(("message in "));
+		return esp_do_msgin(esp, eregs, dregs);
+
+	case in_msgincont:
+		ESPBUS(("continue message in "));
+		return esp_do_msgincont(esp, eregs, dregs);
+
+	case in_msgindone:
+		ESPBUS(("finish message in "));
+		return esp_do_msgindone(esp, eregs, dregs);
+
 	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;
+		ESPBUS(("status phase "));
+		return esp_do_status(esp, eregs, dregs);
+
+	case in_freeing:
+		ESPBUS(("freeing the bus "));
+		return esp_do_freebus(esp, eregs, dregs);
+
+	case in_cmdbegin:
+		ESPBUS(("begin slow cmd "));
+		return esp_do_cmdbegin(esp, eregs, dregs);
+
+	case in_cmdend:
+		ESPBUS(("end slow cmd "));
+		return esp_do_cmddone(esp, eregs, dregs);
+
+	default:
+		printk("esp%d: command in weird state %2x\n",
+		       esp->esp_id, esp->current_SC->SCp.phase);
+		return do_reset_bus;
+	};
+}
+
+/* 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;
+	int what_next = do_intr_end;
+
+	eregs = esp->eregs;
+	dregs = esp->dregs;
+	SCptr = esp->current_SC;
+
+	DMA_IRQ_ENTRY(esp->dma, dregs);
+
+	/* 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 again;
+		}
+	}
+
+	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 %08lx\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 again;
+	}
+
+	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_hwbug_workaround(esp, eregs);
 		} else {
-			panic("esp: penguin status phase.");
+			ESPHME(("no_fifo_workaround]"));
 		}
-	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;
+	}
+
+	esp->ireg = eregs->esp_intrpt;   /* Unlatch intr and stat regs */
+
+	/* 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;
+		goto again;
+	}
+
+	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));
+				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.");
+			ESPLOG(("esp%d: BSERV or FDONE or DC while SCptr==NULL\n",
+				esp->esp_id));
+			what_next = do_reset_bus;
+			goto again;
+		}
+	} 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;
+		goto again;
+	} 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;
+			goto again;
+		}
+	}
+
+	/* We're trying to fight stack problems, and inline as much as
+	 * possible without making this driver a mess. hate hate hate
+	 * This is tier-one in our dual level SCSI state machine.
+	 */
+again:
+	switch(what_next) {
+	case do_intr_end:
+		goto esp_handle_done;
+
+	case do_work_bus:
+		what_next = esp_work_bus(esp, eregs, dregs);
+		break;
+
+	case do_phase_determine:
+		what_next = esp_do_phase_determine(esp, eregs, dregs);
+		break;
+
+	case do_reset_bus:
+		ESPLOG(("esp%d: resetting bus...\n", esp->esp_id));
+		esp->resetting_bus = 1;
+		esp_cmd(esp, eregs, ESP_CMD_RS);
+		goto esp_handle_done;
+
+	case do_reset_complete:
+		/* Tricky, we don't want to cause any more commands to
+		 * go out until we clear all the live cmds by hand.
+		 */
+		if(!DMA_ISBROKEN(esp->dma))
+			DMA_INTSOFF(dregs);
+		if(esp->current_SC) {
+			Scsi_Cmnd *SCptr = esp->current_SC;
+			if(!SCptr->use_sg)
+				mmu_release_scsi_one((char *)
+						     SCptr->SCp.have_data_in,
+						     SCptr->request_bufflen,
+						     esp->edev->my_bus);
+			else
+				mmu_release_scsi_sgl((struct mmu_sglist *)
+						     SCptr->buffer,
+						     SCptr->use_sg - 1,
+						     esp->edev->my_bus);
+			SCptr->result = (DID_RESET << 16);
+			SCptr->scsi_done(SCptr);
+			cli();
+		}
+		esp->current_SC = NULL;
+		if(esp->disconnected_SC) {
+			Scsi_Cmnd *SCptr;
+			while((SCptr = remove_first_SC(&esp->disconnected_SC))) {
+				if(!SCptr->use_sg)
+					mmu_release_scsi_one((char *)
+							     SCptr->SCp.have_data_in,
+							     SCptr->request_bufflen,
+							     esp->edev->my_bus);
+				else
+					mmu_release_scsi_sgl((struct mmu_sglist *)
+							     SCptr->buffer,
+							     SCptr->use_sg - 1,
+							     esp->edev->my_bus);
+				SCptr->result = (DID_RESET << 16);
+				SCptr->scsi_done(SCptr);
+				cli();
+			}
+		}
+		esp->resetting_bus = 0;
+		if(!DMA_ISBROKEN(esp->dma))
+			DMA_INTSON(dregs);
+
+		if(esp->current_SC) {
+			printk("esp%d: weird weird weird, current_SC not NULL after "
+			       "SCSI bus reset.\n", esp->esp_id);
 			goto esp_handle_done;
 		}
-	default:
-		panic("esp: detected penguin phase.");
+
+		/* Now it is safe to execute more things. */
+		if(esp->issue_SC)
+			esp_exec_cmd(esp);
 		goto esp_handle_done;
-	}
-	panic("esp: Heading to the promised land.");
+
+	default:
+		/* state is completely lost ;-( */
+		ESPLOG(("esp%d: interrupt engine loses state, resetting bus\n",
+			esp->esp_id));
+		what_next = do_reset_bus;
+		break;
+
+	};
+	goto again;
 
 esp_handle_done:
 	DMA_IRQ_EXIT(esp->dma, dregs);
@@ -1118,11 +4057,28 @@
 static void esp_intr(int irq, void *dev_id, struct pt_regs *pregs)
 {
 	struct Sparc_ESP *esp;
+	static int running = 0;
+	int again;
+
+	/* It is ok to take irq's on one esp while the other
+	 * is amidst the processing of a reset.
+	 */
+	running++;
+	if(running > esps_running)
+		ESPLOG(("esp_intr: yieee, recursive interrupt!\n"));
 
 	/* Handle all ESP interrupts showing */
+repeat:
+	again = 0;
 	for_each_esp(esp) {
 		if(DMA_IRQ_P(esp->dregs)) {
+			again = 1;
+			ESPIRQ(("I%d(", esp->esp_id));
 			esp_handle(esp);
+			ESPIRQ((")"));
 		}
 	}
+	if(again)
+		goto repeat;
+	running--;
 }

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TCL-scripts by Sam Shen, slshen@lbl.gov