patch-1.3.4 linux/drivers/scsi/aha274x.c

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diff -u --recursive --new-file v1.3.3/linux/drivers/scsi/aha274x.c linux/drivers/scsi/aha274x.c
@@ -1,1490 +0,0 @@
-/*
- *  @(#)aha274x.c 1.29 94/10/29 jda
- *
- *  Adaptec 274x device driver for Linux.
- *  Copyright (c) 1994 The University of Calgary Department of Computer Science.
- *  
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
- *  
- *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  GNU General Public License for more details.
- *  
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- *  Sources include the Adaptec 1740 driver (aha1740.c), the
- *  Ultrastor 24F driver (ultrastor.c), various Linux kernel
- *  source, the Adaptec EISA config file (!adp7771.cfg), the
- *  Adaptec AHA-2740A Series User's Guide, the Linux Kernel
- *  Hacker's Guide, Writing a SCSI Device Driver for Linux,
- *  the Adaptec 1542 driver (aha1542.c), the Adaptec EISA
- *  overlay file (adp7770.ovl), the Adaptec AHA-2740 Series
- *  Technical Reference Manual, the Adaptec AIC-7770 Data
- *  Book, the ANSI SCSI specification, the ANSI SCSI-2
- *  specification (draft 10c), ...
- *
- *  On a twin-bus adapter card, channel B is ignored.  Rationale:
- *  it would greatly complicate the sequencer and host driver code,
- *  and both busses are multiplexed on to the EISA bus anyway.  So
- *  I don't really see any technical advantage to supporting both.
- *
- *  As well, multiple adapter card using the same IRQ level are
- *  not supported.  It doesn't make sense to configure the cards
- *  this way from a performance standpoint.  Not to mention that
- *  the kernel would have to support two devices per registered IRQ.
- */
-
-#include <stdarg.h>
-#include <asm/io.h>
-#include <linux/string.h>
-#include <linux/kernel.h>
-#include <linux/ioport.h>
-#include <linux/delay.h>
-
-#include "../block/blk.h"
-#include "sd.h"
-#include "scsi.h"
-#include "hosts.h"
-#include "aha274x.h"
-
-/*
- *  There should be a specific return value for this in scsi.h, but
- *  it seems that most drivers ignore it.
- */
-#define DID_UNDERFLOW	DID_ERROR
-
-/* EISA stuff */
-
-#define MINEISA		1
-#define MAXEISA		15
-#define SLOTBASE(x)	((x) << 12)
-
-#define MAXIRQ		15
-
-/* AIC-7770 offset definitions */
-
-#define O_MINREG(x)	((x) + 0xc00)		/* i/o range to reserve */
-#define O_MAXREG(x)	((x) + 0xcbf)
-
-#define O_SCSISEQ(x)	((x) + 0xc00)		/* scsi sequence control */
-#define O_SCSISIGI(x)	((x) + 0xc03)		/* scsi control signal read */
-#define O_SCSISIGO(x)	((x) + 0xc03)		/* scsi control signal write */
-#define O_SCSIID(x)	((x) + 0xc05)		/* scsi id */
-#define O_SSTAT0(x)	((x) + 0xc0b)		/* scsi status register 0 */
-#define O_CLRSINT1(x)	((x) + 0xc0c)		/* clear scsi interrupt 1 */
-#define O_SSTAT1(x)	((x) + 0xc0c)		/* scsi status register 1 */
-#define O_SELID(x)	((x) + 0xc19)		/* [re]selection id */
-#define O_SBLKCTL(x)	((x) + 0xc1f)		/* scsi block control */
-#define O_SEQCTL(x)	((x) + 0xc60)		/* sequencer control */
-#define O_SEQRAM(x)	((x) + 0xc61)		/* sequencer ram data */
-#define O_SEQADDR(x)	((x) + 0xc62)		/* sequencer address (W) */
-#define O_BIDx(x)	((x) + 0xc80)		/* board id */
-#define O_BCTL(x)	((x) + 0xc84)		/* board control */
-#define O_HCNTRL(x)	((x) + 0xc87)		/* host control */
-#define O_SCBPTR(x)	((x) + 0xc90)		/* scb pointer */
-#define O_INTSTAT(x)	((x) + 0xc91)		/* interrupt status */
-#define O_ERROR(x)	((x) + 0xc92)		/* hard error */
-#define O_CLRINT(x)	((x) + 0xc92)		/* clear interrupt status */
-#define O_SCBCNT(x)	((x) + 0xc9a)		/* scb auto increment */
-#define O_QINFIFO(x)	((x) + 0xc9b)		/* queue in fifo */
-#define O_QINCNT(x)	((x) + 0xc9c)		/* queue in count */
-#define O_QOUTFIFO(x)	((x) + 0xc9d)		/* queue out fifo */
-#define O_QOUTCNT(x)	((x) + 0xc9e)		/* queue out count */
-#define O_SCBARRAY(x)	((x) + 0xca0)		/* scb array start */
-
-/* host adapter offset definitions */
-
-#define HA_REJBYTE(x)	((x) + 0xc31)		/* 1st message in byte */
-#define HA_MSG_FLAGS(x)	((x) + 0xc35)		/* outgoing message flag */
-#define HA_MSG_LEN(x)	((x) + 0xc36)		/* outgoing message length */
-#define HA_MSG_START(x)	((x) + 0xc37)		/* outgoing message body */
-#define HA_ARG_1(x)	((x) + 0xc4c)		/* sdtr <-> rate parameters */
-#define HA_ARG_2(x)	((x) + 0xc4d)
-#define HA_RETURN_1(x)	((x) + 0xc4c)
-#define HA_RETURN_2(x)	((x) + 0xc4d)
-#define HA_SIGSTATE(x)	((x) + 0xc4e)		/* value in SCSISIGO */
-#define HA_NEEDSDTR(x)	((x) + 0xc4f)		/* synchronous negotiation? */
-
-#define HA_SCSICONF(x)	((x) + 0xc5a)		/* SCSI config register */
-#define HA_INTDEF(x)	((x) + 0xc5c)		/* interrupt def'n register */
-#define HA_HOSTCONF(x)	((x) + 0xc5d)		/* host config def'n register */
-
-/* debugging code */
-
-#define AHA274X_DEBUG
-
-/*
- *  If a parity error occurs during a data transfer phase, run the
- *  command to completion - it's easier that way - making a note
- *  of the error condition in this location.  This then will modify
- *  a DID_OK status into a DID_PARITY one for the higher-level SCSI
- *  code.
- */
-#define aha274x_parity(cmd)	((cmd)->SCp.Status)
-
-/*
- *  Since the sequencer code DMAs the scatter-gather structures
- *  directly from memory, we use this macro to assert that the
- *  kernel structure hasn't changed.
- */
-#define SG_STRUCT_CHECK(sg) \
-	((char *)&(sg).address - (char *)&(sg) != 0 ||	\
-	 (char *)&(sg).length  - (char *)&(sg) != 8 ||	\
-	 sizeof((sg).address) != 4 ||			\
-	 sizeof((sg).length)  != 4 ||			\
-	 sizeof(sg)	      != 12)
-
-/*
- *  "Static" structures.  Note that these are NOT initialized
- *  to zero inside the kernel - we have to initialize them all
- *  explicitly.
- *
- *  We support a maximum of one adapter card per IRQ level (see the
- *  rationale for this above).  On an interrupt, use the IRQ as an
- *  index into aha274x_boards[] to locate the card information.
- */
-static struct Scsi_Host *aha274x_boards[MAXIRQ + 1];
-
-struct aha274x_host {
-	int base;					/* card base address */
-	int startup;					/* intr type check */
-	volatile int unpause;				/* value for HCNTRL */
-	volatile Scsi_Cmnd *SCB_array[AHA274X_MAXSCB];	/* active commands */
-};
-
-struct aha274x_scb {
-	unsigned char control;
-	unsigned char target_channel_lun;		/* 4/1/3 bits */
-	unsigned char SG_segment_count;
-	unsigned char SG_list_pointer[4];
-	unsigned char SCSI_cmd_pointer[4];
-	unsigned char SCSI_cmd_length;
-	unsigned char RESERVED[2];			/* must be zero */
-	unsigned char target_status;
-	unsigned char residual_data_count[3];
-	unsigned char residual_SG_segment_count;
-	unsigned char data_pointer[4];
-	unsigned char data_count[3];
-#if 0
-	/*
-	 *  No real point in transferring this to the
-	 *  SCB registers.
-	 */
-	unsigned char RESERVED[6];
-#endif
-};
-
-/*
- *  NB.  This table MUST be ordered shortest period first.
- */
-static struct {
-	short period;
-	short rate;
-	char *english;
-} aha274x_synctab[] = {
-	{100,	0,	"10.0"},
-	{125,	1,	"8.0"},
-	{150,	2,	"6.67"},
-	{175,	3,	"5.7"},
-	{200,	4,	"5.0"},
-	{225,	5,	"4.4"},
-	{250,	6,	"4.0"},
-	{275,	7,	"3.6"}
-};
-
-static int aha274x_synctab_max =
-	sizeof(aha274x_synctab) / sizeof(aha274x_synctab[0]);
-
-enum aha_type {
-	T_NONE,
-	T_274X,
-	T_284X,
-	T_MAX
-};
-
-#ifdef AHA274X_DEBUG
-
-	extern int vsprintf(char *, const char *, va_list);
-
-	static
-	void debug(const char *fmt, ...)
-	{
-		va_list ap;
-		char buf[256];
-
-		va_start(ap, fmt);
-		  vsprintf(buf, fmt, ap);
-		  printk(buf);
-		va_end(ap);
-	}
-
-	static
-	void debug_config(enum aha_type type, int base)
-	{
-		int ioport2, ioport3, ioport4;
-
-		static char *BRT[T_MAX][16] = {
-			{ },					/* T_NONE */
-			{
-				"2",   "???", "???", "12",	/* T_274X */
-				"???", "???", "???", "28",
-				"???", "???", "???", "44",
-				"???", "???", "???", "60"
-			},
-			{
-				"2",  "4",  "8",  "12",		/* T_284X */
-				"16", "20", "24", "28",
-				"32", "36", "40", "44",
-				"48", "52", "56", "60"
-			}
-		};
-		static int DFT[4] = {
-			0, 50, 75, 100
-		};
-		static int SST[4] = {
-			256, 128, 64, 32
-		};
-
-		ioport2 = inb(HA_HOSTCONF(base));
-		ioport3 = inb(HA_SCSICONF(base));
-		ioport4 = inb(HA_INTDEF(base));
-
-		if (type == T_284X)
-			printk("AHA284X AT SLOT %d:\n", base >> 12);
-		else
-			printk("AHA274X AT EISA SLOT %d:\n", base >> 12);
-
-		printk("    irq %d\n"
-		       "    bus release time %s bclks\n"
-		       "    data fifo threshold %d%%\n",
-		       ioport4 & 0xf,
-		       BRT[type][(ioport2 >> 2) & 0xf],
-		       DFT[(ioport2 >> 6) & 0x3]);
-
-		printk("    SCSI CHANNEL A:\n"
-		       "        scsi id %d\n"
-		       "        scsi bus parity check %sabled\n"
-		       "        scsi selection timeout %d ms\n"
-		       "        scsi bus reset at power-on %sabled\n",
-		       ioport3 & 0x7,
-		       (ioport3 & 0x20) ? "en" : "dis",
-		       SST[(ioport3 >> 3) & 0x3],
-		       (ioport3 & 0x40) ? "en" : "dis");
-
-		if (type == T_274X) {
-			printk("        scsi bus termination %sabled\n",
-			       (ioport3 & 0x80) ? "en" : "dis");
-		}
-	}
-
-	static
-	void debug_rate(int base, int rate)
-	{
-		int target = inb(O_SCSIID(base)) >> 4;
-
-		if (rate) {
-			printk("aha274x: target %d now synchronous at %sMb/s\n",
-			       target,
-			       aha274x_synctab[(rate >> 4) & 0x7].english);
-		} else {
-			printk("aha274x: target %d using asynchronous mode\n",
-			       target);
-		}
-	}
-
-#else
-
-#	define debug(fmt, args...)
-#	define debug_config(x)
-#	define debug_rate(x,y)
-
-#endif AHA274X_DEBUG
-
-/*
- *  XXX - these options apply unilaterally to _all_ 274x/284x
- *	  cards in the system.  This should be fixed, but then,
- *	  does anyone really have more than one in a machine?
- */
-static int aha274x_extended = 0;		/* extended translation on? */
-
-void aha274x_setup(char *s, int *dummy)
-{
-	int i;
-	char *p;
-
-	static struct {
-		char *name;
-		int *flag;
-	} options[] = {
-		{"extended",	&aha274x_extended},
-		{NULL, NULL }
-	};
-
-	for (p = strtok(s, ","); p; p = strtok(NULL, ",")) {
-		for (i = 0; options[i].name; i++)
-			if (!strcmp(options[i].name, p))
-				*(options[i].flag) = !0;
-	}
-}
-
-static
-void aha274x_getscb(int base, struct aha274x_scb *scb)
-{
-	/*
-	 *  This is almost identical to aha274x_putscb().
-	 */
-	outb(0x80, O_SCBCNT(base));	/* SCBAUTO */
-
-	asm volatile("cld\n\t"
-		     "rep\n\t"
-		     "insb"
-		     : /* no output */
-		     :"D" (scb), "c" (sizeof(*scb)), "d" (O_SCBARRAY(base))
-		     :"di", "cx", "dx");
-
-	outb(0, O_SCBCNT(base));
-}
-
-/*
- *  How much data should be transferred for this SCSI command?  Stop
- *  at segment sg_last if it's a scatter-gather command so we can
- *  compute underflow easily.
- */
-static
-unsigned aha274x_length(Scsi_Cmnd *cmd, int sg_last)
-{
-	int i, segments;
-	unsigned length;
-	struct scatterlist *sg;
-
-	segments = cmd->use_sg - sg_last;
-	sg = (struct scatterlist *)cmd->buffer;
-
-	if (cmd->use_sg) {
-		for (i = length = 0;
-		     i < cmd->use_sg && i < segments;
-		     i++)
-		{
-			length += sg[i].length;
-		}
-	} else
-		length = cmd->request_bufflen;
-
-	return(length);
-}
-
-static
-void aha274x_sg_check(Scsi_Cmnd *cmd)
-{
-	int i;
-	struct scatterlist *sg = (struct scatterlist *)cmd->buffer;
-
-	if (cmd->use_sg) {
-		for (i = 0; i < cmd->use_sg; i++)
-			if ((unsigned)sg[i].length > 0xffff)
-				panic("aha274x_sg_check: s/g segment > 64k\n");
-	}
-}
-
-static
-void aha274x_to_scsirate(unsigned char *rate,
-			 unsigned char transfer,
-			 unsigned char offset)
-{
-	int i;
-
-	transfer *= 4;
-
-	for (i = 0; i < aha274x_synctab_max-1; i++) {
-
-		if (transfer == aha274x_synctab[i].period) {
-			*rate = (aha274x_synctab[i].rate << 4) | (offset & 0xf);
-			return;
-		}
-
-		if (transfer > aha274x_synctab[i].period &&
-		    transfer < aha274x_synctab[i+1].period)
-		{
-			*rate = (aha274x_synctab[i+1].rate << 4) |
-				(offset & 0xf);
-			return;
-		}
-	}
-	*rate = 0;
-}
-
-/*
- *  Pause the sequencer and wait for it to actually stop - this
- *  is important since the sequencer can disable pausing for critical
- *  sections.
- */
-#define PAUSE_SEQUENCER(p)	\
-	do {								\
-		outb(0xe, O_HCNTRL(p->base));	/* IRQMS|PAUSE|INTEN */	\
-									\
-		while ((inb(O_HCNTRL(p->base)) & 0x4) == 0)		\
-			;						\
-	} while (0)
-
-/*
- *  Unpause the sequencer.  Unremarkable, yet done often enough to
- *  warrant an easy way to do it.
- */
-#define UNPAUSE_SEQUENCER(p)	\
-	outb(p->unpause, O_HCNTRL(p->base))	/* IRQMS|INTEN */
-
-/*
- *  See comments in aha274x_loadram() wrt this.
- */
-#define RESTART_SEQUENCER(p)	\
-	do {						\
-		do {					\
-			outb(0x2, O_SEQCTL(p->base));	\
-		} while (inw(O_SEQADDR(p->base)) != 0);	\
-							\
-		UNPAUSE_SEQUENCER(p);			\
-	} while (0)
-
-/*
- *  Since we declared this using SA_INTERRUPT, interrupts should
- *  be disabled all through this function unless we say otherwise.
- */
-static
-void aha274x_isr(int irq, struct pt_regs * regs)
-{
-	int base, intstat;
-	struct aha274x_host *p;
-	
-	p = (struct aha274x_host *)aha274x_boards[irq]->hostdata;
-	base = p->base;
-
-	/*
-	 *  Check the startup flag - if no commands have been queued,
-	 *  we probably have the interrupt type set wrong.  Reverse
-	 *  the stored value and the active one in the host control
-	 *  register.
-	 */
-	if (p->startup) {
-		p->unpause ^= 0x8;
-		outb(inb(O_HCNTRL(p->base)) ^ 0x8, O_HCNTRL(p->base));
-		return;
-	}
-
-	/*
-	 *  Handle all the interrupt sources - especially for SCSI
-	 *  interrupts, we won't get a second chance at them.
-	 */
-	intstat = inb(O_INTSTAT(base));
-
-	if (intstat & 0x8) {				/* BRKADRINT */
-
-		panic("aha274x_isr: brkadrint, error = 0x%x, seqaddr = 0x%x\n",
-		      inb(O_ERROR(base)), inw(O_SEQADDR(base)));
-	}
-
-	if (intstat & 0x4) {				/* SCSIINT */
-
-		int scbptr = inb(O_SCBPTR(base));
-		int status = inb(O_SSTAT1(base));
-		Scsi_Cmnd *cmd;
-
-		cmd = (Scsi_Cmnd *)p->SCB_array[scbptr];
-		if (!cmd) {
-			printk("aha274x_isr: no command for scb (scsiint)\n");
-			/*
-			 *  Turn off the interrupt and set status
-			 *  to zero, so that it falls through the
-			 *  reset of the SCSIINT code.
-			 */
-			outb(status, O_CLRSINT1(base));
-			UNPAUSE_SEQUENCER(p);
-			outb(0x4, O_CLRINT(base));	/* undocumented */
-			status = 0;
-		}
-		p->SCB_array[scbptr] = NULL;
-
-		/*
-		 *  Only the SCSI Status 1 register has information
-		 *  about exceptional conditions that we'd have a
-		 *  SCSIINT about; anything in SSTAT0 will be handled
-		 *  by the sequencer.  Note that there can be multiple
-		 *  bits set.
-		 */
-		if (status & 0x80) {			/* SELTO */
-			/*
-			 *  Hardware selection timer has expired.  Turn
-			 *  off SCSI selection sequence.
-			 */
-			outb(0, O_SCSISEQ(base));
-			cmd->result = DID_TIME_OUT << 16;
-
-			/*
-			 *  If there's an active message, it belongs to the
-			 *  command that is getting punted - remove it.
-			 */
-			outb(0, HA_MSG_FLAGS(base));
-
-			/*
-			 *  Shut off the offending interrupt sources, reset
-			 *  the sequencer address to zero and unpause it,
-			 *  then call the high-level SCSI completion routine.
-			 *
-			 *  WARNING!  This is a magic sequence!  After many
-			 *  hours of guesswork, turning off the SCSI interrupts
-			 *  in CLRSINT? does NOT clear the SCSIINT bit in
-			 *  INTSTAT.  By writing to the (undocumented, unused
-			 *  according to the AIC-7770 manual) third bit of
-			 *  CLRINT, you can clear INTSTAT.  But, if you do it
-			 *  while the sequencer is paused, you get a BRKADRINT
-			 *  with an Illegal Host Address status, so the
-			 *  sequencer has to be restarted first.
-			 */
-			outb(0x80, O_CLRSINT1(base));	/* CLRSELTIMO */
-			RESTART_SEQUENCER(p);
-
-			outb(0x4, O_CLRINT(base));	/* undocumented */
-			cmd->scsi_done(cmd);
-		}
-
-		if (status & 0x4) {			/* SCSIPERR */
-			/*
-			 *  A parity error has occurred during a data
-			 *  transfer phase.  Flag it and continue.
-			 */
-			printk("aha274x: parity error on target %d, lun %d\n",
-			       cmd->target,
-			       cmd->lun);
-			aha274x_parity(cmd) = DID_PARITY;
-
-			/*
-			 *  Clear interrupt and resume as above.
-			 */
-			outb(0x4, O_CLRSINT1(base));	/* CLRSCSIPERR */
-			UNPAUSE_SEQUENCER(p);
-
-			outb(0x4, O_CLRINT(base));	/* undocumented */
-		}
-
-		if ((status & (0x8|0x4)) == 0 && status) {
-			/*
-			 *  We don't know what's going on.  Turn off the
-			 *  interrupt source and try to continue.
-			 */
-			printk("aha274x_isr: sstat1 = 0x%x\n", status);
-			outb(status, O_CLRSINT1(base));
-			UNPAUSE_SEQUENCER(p);
-			outb(0x4, O_CLRINT(base));	/* undocumented */
-		}
-	}
-
-	if (intstat & 0x2) {				/* CMDCMPLT */
-
-		int complete, old_scbptr;
-		struct aha274x_scb scb;
-		unsigned actual;
-		Scsi_Cmnd *cmd;
-
-		/*
-		 *  The sequencer will continue running when it
-		 *  issues this interrupt.  There may be >1 commands
-		 *  finished, so loop until we've processed them all.
-		 */
-		do {
-			complete = inb(O_QOUTFIFO(base));
-
-			cmd = (Scsi_Cmnd *)p->SCB_array[complete];
-			if (!cmd) {
-				printk("aha274x warning: "
-				       "no command for scb (cmdcmplt)\n");
-				continue;
-			}
-			p->SCB_array[complete] = NULL;
-			
-			PAUSE_SEQUENCER(p);
-
-			/*
-			 *  After pausing the sequencer (and waiting
-			 *  for it to stop), save its SCB pointer, then
-			 *  write in our completed one and read the SCB
-			 *  registers.  Afterwards, restore the saved
-			 *  pointer, unpause the sequencer and call the
-			 *  higher-level completion function - unpause
-			 *  first since we have no idea how long done()
-			 *  will take.
-			 */
-			old_scbptr = inb(O_SCBPTR(base));
-			outb(complete, O_SCBPTR(base));
-
-			aha274x_getscb(base, &scb);
-			outb(old_scbptr, O_SCBPTR(base));
-
-			UNPAUSE_SEQUENCER(p);
-
-			cmd->result = scb.target_status |
-				     (aha274x_parity(cmd) << 16);
-
-			/*
-			 *  Did we underflow?  At this time, there's only
-			 *  one other driver that bothers to check for this,
-			 *  and cmd->underflow seems to be set rather half-
-			 *  heartedly in the higher-level SCSI code.
-			 */
-			actual = aha274x_length(cmd,
-						scb.residual_SG_segment_count);
-
-			actual -= ((scb.residual_data_count[2] << 16) |
-				   (scb.residual_data_count[1] <<  8) |
-				   (scb.residual_data_count[0]));
-
-			if (actual < cmd->underflow) {
-				printk("aha274x: target %d underflow - "
-				       "wanted (at least) %u, got %u\n",
-				       cmd->target, cmd->underflow, actual);
-
-				cmd->result = scb.target_status |
-					     (DID_UNDERFLOW << 16);
-			}
-
-			cmd->scsi_done(cmd);
-
-			/*
-			 *  Clear interrupt status before checking
-			 *  the output queue again.  This eliminates
-			 *  a race condition whereby a command could
-			 *  complete between the queue poll and the
-			 *  interrupt clearing, so notification of the
-			 *  command being complete never made it back
-			 *  up to the kernel.
-			 */
-			outb(0x2, O_CLRINT(base));	/* CLRCMDINT */
-
-		} while (inb(O_QOUTCNT(base)));
-	}
-
-	if (intstat & 0x1) {				/* SEQINT */
-
-		unsigned char transfer, offset, rate;
-
-		/*
-		 *  Although the sequencer is paused immediately on
-		 *  a SEQINT, an interrupt for a SCSIINT or a CMDCMPLT
-		 *  condition will have unpaused the sequencer before
-		 *  this point.
-		 */
-		PAUSE_SEQUENCER(p);
-
-		switch (intstat & 0xf0) {
-		    case 0x00:
-			panic("aha274x_isr: unknown scsi bus phase\n");
-		    case 0x10:
-			debug("aha274x_isr warning: "
-			      "issuing message reject, 1st byte 0x%x\n",
-			      inb(HA_REJBYTE(base)));
-			break;
-		    case 0x20:
-			panic("aha274x_isr: reconnecting target %d "
-			      "didn't issue IDENTIFY message\n",
-			      (inb(O_SELID(base)) >> 4) & 0xf);
-		    case 0x30:
-			debug("aha274x_isr: sequencer couldn't find match "
-			      "for reconnecting target %d - issuing ABORT\n",
-			      (inb(O_SELID(base)) >> 4) & 0xf);
-			break;
-		    case 0x40:
-			transfer = inb(HA_ARG_1(base));
-			offset = inb(HA_ARG_2(base));
-			aha274x_to_scsirate(&rate, transfer, offset);
-			outb(rate, HA_RETURN_1(base));
-			debug_rate(base, rate);
-			break;
-		    default:
-			debug("aha274x_isr: seqint, "
-			      "intstat = 0x%x, scsisigi = 0x%x\n",
-			      intstat, inb(O_SCSISIGI(base)));
-			break;
-		}
-
-		outb(0x1, O_CLRINT(base));		/* CLRSEQINT */
-		UNPAUSE_SEQUENCER(p);
-	}
-}
-
-/*
- *  Probing for EISA boards: it looks like the first two bytes
- *  are a manufacturer code - three characters, five bits each:
- *
- *		 BYTE 0   BYTE 1   BYTE 2   BYTE 3
- *		?1111122 22233333 PPPPPPPP RRRRRRRR
- *
- *  The characters are baselined off ASCII '@', so add that value
- *  to each to get the real ASCII code for it.  The next two bytes
- *  appear to be a product and revision number, probably vendor-
- *  specific.  This is what is being searched for at each port,
- *  and what should probably correspond to the ID= field in the
- *  ECU's .cfg file for the card - if your card is not detected,
- *  make sure your signature is listed in the array.
- *
- *  The fourth byte's lowest bit seems to be an enabled/disabled
- *  flag (rest of the bits are reserved?).
- */
-
-static
-enum aha_type aha274x_probe(int slot, int s_base)
-{
-	int i;
-	unsigned char buf[4];
-
-	static struct {
-		int n;
-		unsigned char signature[sizeof(buf)];
-		enum aha_type type;
-	} S[] = {
-		{4, { 0x04, 0x90, 0x77, 0x71 }, T_274X},	/* host adapter 274x */
-		{4, { 0x04, 0x90, 0x77, 0x70 }, T_274X},	/* motherboard 274x  */
-		{4, { 0x04, 0x90, 0x77, 0x56 }, T_284X},	/* 284x, BIOS enabled */
-	};
-
-	for (i = 0; i < sizeof(buf); i++) {
-		/*
-		 *  The VL-bus cards need to be primed by
-		 *  writing before a signature check.
-		 */
-		outb(0x80 + i, s_base);
-		buf[i] = inb(s_base + i);
-	}
-
-	for (i = 0; i < sizeof(S)/sizeof(S[0]); i++) {
-		if (!memcmp(buf, S[i].signature, S[i].n)) {
-			/*
-			 *  Signature match on enabled card?
-			 */
-			if (inb(s_base + 4) & 1)
-				return(S[i].type);
-			printk("aha274x disabled at slot %d, ignored\n", slot);
-		}
-	}
-	return(T_NONE);
-}
-
-/*
- *  Return ' ' for plain 274x, 'T' for twin-channel, 'W' for
- *  wide channel, '?' for anything else.
- */
-
-static
-char aha274x_type(int base)
-{
-	/*
-	 *  The AIC-7770 can be wired so that, on chip reset,
-	 *  the SCSI Block Control register indicates how many
-	 *  busses the chip is configured for.
-	 */
-	switch (inb(O_SBLKCTL(base))) {
-	    case 0:
-		return(' ');
-	    case 2:
-		return('W');
-	    case 8:
-		return('T');
-	    default:
-		printk("aha274x has unknown bus configuration\n");
-		return('?');
-	}
-}
-
-static
-void aha274x_loadram(int base)
-{
-	static unsigned char seqprog[] = {
-		/*
-		 *  Each sequencer instruction is 29 bits
-		 *  long (fill in the excess with zeroes)
-		 *  and has to be loaded from least -> most
-		 *  significant byte, so this table has the
-		 *  byte ordering reversed.
-		 */
-#		include "aha274x_seq.h"
-	};
-
-	/*
-	 *  When the AIC-7770 is paused (as on chip reset), the
-	 *  sequencer address can be altered and a sequencer
-	 *  program can be loaded by writing it, byte by byte, to
-	 *  the sequencer RAM port - the Adaptec documentation
-	 *  recommends using REP OUTSB to do this, hence the inline
-	 *  assembly.  Since the address autoincrements as we load
-	 *  the program, reset it back to zero afterward.  Disable
-	 *  sequencer RAM parity error detection while loading, and
-	 *  make sure the LOADRAM bit is enabled for loading.
-	 */
-	outb(0x83, O_SEQCTL(base));	/* PERRORDIS|SEQRESET|LOADRAM */
-
-	asm volatile("cld\n\t"
-		     "rep\n\t"
-		     "outsb"
-		     : /* no output */
-		     :"S" (seqprog), "c" (sizeof(seqprog)), "d" (O_SEQRAM(base))
-		     :"si", "cx", "dx");
-
-	/*
-	 *  WARNING!  This is a magic sequence!  After extensive
-	 *  experimentation, it seems that you MUST turn off the
-	 *  LOADRAM bit before you play with SEQADDR again, else
-	 *  you will end up with parity errors being flagged on
-	 *  your sequencer program.  (You would also think that
-	 *  turning off LOADRAM and setting SEQRESET to reset the
-	 *  address to zero would work, but you need to do it twice
-	 *  for it to take effect on the address.  Timing problem?)
-	 */
-	outb(0, O_SEQCTL(base));
-	do {
-		/*
-		 *  Actually, reset it until
-		 *  the address shows up as
-		 *  zero just to be safe..
-		 */
-		outb(0x2, O_SEQCTL(base));	/* SEQRESET */
-
-	} while (inw(O_SEQADDR(base)) != 0);
-}
-
-static
-int aha274x_register(Scsi_Host_Template *template,
-		     enum aha_type type,
-		     int base)
-{
-	int i, irq, scsi_id;
-	struct Scsi_Host *host;
-	struct aha274x_host *p;
-
-	/*
-	 *  Give the AIC-7770 a reset - reading the 274x's registers
-	 *  returns zeroes unless you do.  This forces a pause of the
-	 *  Sequencer.
-	 */
-	outb(1, O_HCNTRL(base));	/* CHIPRST */
-
-	/*
-	 *  The IRQ level in i/o port 4 maps directly onto the real
-	 *  IRQ number.  If it's ok, register it with the kernel.
-	 *
-	 *  NB. the Adaptec documentation says the IRQ number is only
-	 *	in the lower four bits; the ECU information shows the
-	 *	high bit being used as well.  Which is correct?
-	 */
-	irq = inb(HA_INTDEF(base)) & 0xf;
-	if (irq < 9 || irq > 15) {
-		printk("aha274x uses unsupported IRQ level, ignoring\n");
-		return(0);
-	}
-	
-	/*
-	 *  Lock out other contenders for our i/o space.
-	 */
-	request_region(O_MINREG(base), O_MAXREG(base)-O_MINREG(base), "aha27x");
-
-	/*
-	 *  Any card-type-specific adjustments before we register
-	 *  the scsi host(s).
-	 */
-
-	scsi_id = inb(HA_SCSICONF(base)) & 0x7;
-
-	switch (aha274x_type(base)) {
-	    case 'T':
-		printk("aha274x warning: ignoring channel B of 274x-twin\n");
-		break;
-	    case ' ':
-		break;
-	    default:
-		printk("aha274x is an unsupported type, ignoring\n");
-		return(0);
-	}
-
-	/*
-	 *  Before registry, make sure that the offsets of the
-	 *  struct scatterlist are what the sequencer will expect,
-	 *  otherwise disable scatter-gather altogether until someone
-	 *  can fix it.  This is important since the sequencer will
-	 *  DMA elements of the SG array in while executing commands.
-	 */
-	if (template->sg_tablesize != SG_NONE) {
-		struct scatterlist sg;
-
-		if (SG_STRUCT_CHECK(sg)) {
-			printk("aha274x warning: kernel scatter-gather "
-			       "structures changed, disabling it\n");
-			template->sg_tablesize = SG_NONE;
-		}
-	}
-	
-	/*
-	 *  Register each "host" and fill in the returned Scsi_Host
-	 *  structure as best we can.  Some of the parameters aren't
-	 *  really relevant for EISA, and none of the high-level SCSI
-	 *  code looks at it anyway.. why are the fields there?  Also
-	 *  save the pointer so that we can find the information when
-	 *  an IRQ is triggered.
-	 */
-	host = scsi_register(template, sizeof(struct aha274x_host));
-	host->this_id = scsi_id;
-	host->irq = irq;
-
-	aha274x_boards[irq] = host;
-	
-	p = (struct aha274x_host *)host->hostdata;
-	for (i = 0; i < AHA274X_MAXSCB; i++)
-		p->SCB_array[i] = NULL;
-	p->base = base;
-
-	/*
-	 *  The interrupt trigger is different depending
-	 *  on whether the card is EISA or VL-bus - sometimes.
-	 *  The startup variable will be cleared once the first
-	 *  command is queued, and is checked in the isr to
-	 *  try and detect when the interrupt type is set
-	 *  incorrectly, triggering an interrupt immediately.
-	 */
-	p->unpause = (type != T_274X ? 0x2 : 0xa);
-	p->startup = !0;
-
-	/*
-	 *  Register IRQ with the kernel _after_ the host information
-	 *  is set up, in case we take an interrupt right away, due to
-	 *  the interrupt type being set wrong.
-	 */
-	if (request_irq(irq, aha274x_isr, SA_INTERRUPT, "AHA274x/284x")) {
-		printk("aha274x couldn't register irq %d, ignoring\n", irq);
-		return(0);
-	}
-
-	/*
-	 *  A reminder until this can be detected automatically.
-	 */
-	printk("aha274x: extended translation %sabled\n",
-	       aha274x_extended ? "en" : "dis");
-
-	/*
-	 *  Print out debugging information before re-enabling
-	 *  the card - a lot of registers on it can't be read
-	 *  when the sequencer is active.
-	 */
-	debug_config(type, base);
-
-	/*
-	 *  Load the sequencer program, then re-enable the board -
-	 *  resetting the AIC-7770 disables it, leaving the lights
-	 *  on with nobody home.
-	 */
-	aha274x_loadram(base);
-	outb(1, O_BCTL(base));		/* ENABLE */
-
-	/*
-	 *  Set the host adapter registers to indicate that synchronous
-	 *  negotiation should be attempted the first time the targets
-	 *  are communicated with.  Also initialize the active message
-	 *  flag to indicate that there is no message.
-	 */
-	outb(0xff, HA_NEEDSDTR(base));
-	outb(0, HA_MSG_FLAGS(base));
-
-	/*
-	 *  Unpause the sequencer before returning and enable
-	 *  interrupts - we shouldn't get any until the first
-	 *  command is sent to us by the high-level SCSI code.
-	 */
-	UNPAUSE_SEQUENCER(p);
-	return(1);
-}
-
-int aha274x_detect(Scsi_Host_Template *template)
-{
-	enum aha_type type;
-	int found = 0, slot, base;
-
-	for (slot = MINEISA; slot <= MAXEISA; slot++) {
-
-		base = SLOTBASE(slot);
-		
-		if (check_region(O_MINREG(base),
-				 O_MAXREG(base)-O_MINREG(base)))
-		{
-			/*
-			 *  Some other driver has staked a
-			 *  claim to this i/o region already.
-			 */
-			continue;
-		}
-
-		type = aha274x_probe(slot, O_BIDx(base));
-
-		if (type != T_NONE) {
-			/*
-			 *  We "find" a 274x if we locate the card
-			 *  signature and we can set it up and register
-			 *  it with the kernel without incident.
-			 */
-			found += aha274x_register(template, type, base);
-		}
-	}
-	template->name = (char *)aha274x_info(NULL);
-	return(found);
-}
-
-const char *aha274x_info(struct Scsi_Host * shost)
-{
-	return("Adaptec AHA274x/284x (EISA/VL-bus -> Fast SCSI) "
-	       AHA274X_SEQ_VERSION "/"
-	       AHA274X_H_VERSION "/"
-	       "1.29");
-}
-
-int aha274x_command(Scsi_Cmnd *cmd)
-{
-	/*
-	 *  This is a relic of non-interrupt-driven SCSI
-	 *  drivers.  With the can_queue variable set, this
-	 *  should never be called.
-	 */
-	panic("aha274x_command was called\n");
-}
-
-static
-void aha274x_buildscb(struct aha274x_host *p,
-		      Scsi_Cmnd *cmd,
-		      struct aha274x_scb *scb)
-{
-	void *addr;
-	unsigned length;
-
-	memset(scb, 0, sizeof(*scb));
-
-	/*
-	 *  NB. channel selection (bit 3) is always zero.
-	 */
-	scb->target_channel_lun = ((cmd->target << 4) & 0xf0) |
-				   (cmd->lun & 0x7);
-
-	/*
-	 *  The interpretation of request_buffer and request_bufflen
-	 *  changes depending on whether or not use_sg is zero; a
-	 *  non-zero use_sg indicates the number of elements in the
-	 *  scatter-gather array.
-	 *
-	 *  The AIC-7770 can't support transfers of any sort larger
-	 *  than 2^24 (three-byte count) without backflips.  For what
-	 *  the kernel is doing, this shouldn't occur.  I hope.
-	 */
-	length = aha274x_length(cmd, 0);
-
-	/*
-	 *  The sequencer code cannot yet handle scatter-gather segments
-	 *  larger than 64k (two-byte length).  The 1.1.x kernels, however,
-	 *  have a four-byte length field in the struct scatterlist, so
-	 *  make sure we don't exceed 64k on these kernels for now.
-	 */
-	aha274x_sg_check(cmd);
-
-	if (length > 0xffffff) {
-		panic("aha274x_buildscb: can't transfer > 2^24 - 1 bytes\n");
-	}
-
-	/*
-	 *  XXX - this relies on the host data being stored in a
-	 *	  little-endian format.
-	 */
-	addr = cmd->cmnd;
-	scb->SCSI_cmd_length = cmd->cmd_len;
-	memcpy(scb->SCSI_cmd_pointer, &addr, sizeof(scb->SCSI_cmd_pointer));
-
-	if (cmd->use_sg) {
-#if 0
-		debug("aha274x_buildscb: SG used, %d segments, length %u\n",
-		      cmd->use_sg,
-		      length);
-#endif
-		scb->SG_segment_count = cmd->use_sg;
-		memcpy(scb->SG_list_pointer,
-		       &cmd->request_buffer,
-		       sizeof(scb->SG_list_pointer));
-	} else {
-		scb->SG_segment_count = 0;
-		memcpy(scb->data_pointer,
-		       &cmd->request_buffer,
-		       sizeof(scb->data_pointer));
-		memcpy(scb->data_count,
-		       &cmd->request_bufflen,
-		       sizeof(scb->data_count));
-	}
-}
-
-static
-void aha274x_putscb(int base, struct aha274x_scb *scb)
-{
-	/*
-	 *  By turning on the SCB auto increment, any reference
-	 *  to the SCB I/O space postincrements the SCB address
-	 *  we're looking at.  So turn this on and dump the relevant
-	 *  portion of the SCB to the card.
-	 */
-	outb(0x80, O_SCBCNT(base));	/* SCBAUTO */
-
-	asm volatile("cld\n\t"
-		     "rep\n\t"
-		     "outsb"
-		     : /* no output */
-		     :"S" (scb), "c" (sizeof(*scb)), "d" (O_SCBARRAY(base))
-		     :"si", "cx", "dx");
-
-	outb(0, O_SCBCNT(base));
-}
-
-int aha274x_queue(Scsi_Cmnd *cmd, void (*fn)(Scsi_Cmnd *))
-{
-	long flags;
-	int empty, old_scbptr;
-	struct aha274x_host *p;
-	struct aha274x_scb scb;
-
-#if 0
-	debug("aha274x_queue: cmd 0x%x (size %u), target %d, lun %d\n",
-	      cmd->cmnd[0],
-	      cmd->cmd_len,
-	      cmd->target,
-	      cmd->lun);
-#endif
-
-	p = (struct aha274x_host *)cmd->host->hostdata;
-
-	/*
-	 *  Construct the SCB beforehand, so the sequencer is
-	 *  paused a minimal amount of time.
-	 */
-	aha274x_buildscb(p, cmd, &scb);
-
-	/*
-	 *  Clear the startup flag - we can now legitimately
-	 *  expect interrupts.
-	 */
-	p->startup = 0;
-
-	/*
-	 *  This is a critical section, since we don't want the
-	 *  interrupt routine mucking with the host data or the
-	 *  card.  Since the kernel documentation is vague on
-	 *  whether or not we are in a cli/sti pair already, save
-	 *  the flags to be on the safe side.
-	 */
-	save_flags(flags);
-	cli();
-
-	/*
-	 *  Find a free slot in the SCB array to load this command
-	 *  into.  Since can_queue is set to AHA274X_MAXSCB, we
-	 *  should always find one.
-	 */
-	for (empty = 0; empty < AHA274X_MAXSCB; empty++)
-		if (!p->SCB_array[empty])
-			break;
-	if (empty == AHA274X_MAXSCB)
-		panic("aha274x_queue: couldn't find a free scb\n");
-
-	/*
-	 *  Pause the sequencer so we can play with its registers -
-	 *  wait for it to acknowledge the pause.
-	 *
-	 *  XXX - should the interrupts be left on while doing this?
-	 */
-	PAUSE_SEQUENCER(p);
-
-	/*
-	 *  Save the SCB pointer and put our own pointer in - this
-	 *  selects one of the four banks of SCB registers.  Load
-	 *  the SCB, then write its pointer into the queue in FIFO
-	 *  and restore the saved SCB pointer.
-	 */
-	old_scbptr = inb(O_SCBPTR(p->base));
-	outb(empty, O_SCBPTR(p->base));
-	
-	aha274x_putscb(p->base, &scb);
-
-	outb(empty, O_QINFIFO(p->base));
-	outb(old_scbptr, O_SCBPTR(p->base));
-
-	/*
-	 *  Make sure the Scsi_Cmnd pointer is saved, the struct it
-	 *  points to is set up properly, and the parity error flag
-	 *  is reset, then unpause the sequencer and watch the fun
-	 *  begin.
-	 */
-	cmd->scsi_done = fn;
-	p->SCB_array[empty] = cmd;
-	aha274x_parity(cmd) = DID_OK;
-
-	UNPAUSE_SEQUENCER(p);
-
-	restore_flags(flags);
-	return(0);
-}
-
-/* return values from aha274x_kill */
-
-enum k_state {
-	k_ok,				/* scb found and message sent */
-	k_busy,				/* message already present */
-	k_absent,			/* couldn't locate scb */
-	k_disconnect,			/* scb found, but disconnected */
-};
-
-/*
- *  This must be called with interrupts disabled - it's going to
- *  be messing around with the host data, and an interrupt being
- *  fielded in the middle could get ugly.
- *
- *  Since so much of the abort and reset code is shared, this
- *  function performs more magic than it really should.  If the
- *  command completes ok, then it will call scsi_done with the
- *  result code passed in.  The unpause parameter controls whether
- *  or not the sequencer gets unpaused - the reset function, for
- *  instance, may want to do something more aggressive.
- *
- *  Note that the command is checked for in our SCB_array first
- *  before the sequencer is paused, so if k_absent is returned,
- *  then the sequencer is NOT paused.
- */
-
-static
-enum k_state aha274x_kill(Scsi_Cmnd *cmd, unsigned char message,
-			  unsigned int result, int unpause)
-{
-	struct aha274x_host *p;
-	int i, scb, found, queued;
-	unsigned char scbsave[AHA274X_MAXSCB];
-
-	p = (struct aha274x_host *)cmd->host->hostdata;
-
-	/*
-	 *  If we can't find the command, assume it just completed
-	 *  and shrug it away.
-	 */
-	for (scb = 0; scb < AHA274X_MAXSCB; scb++)
-		if (p->SCB_array[scb] == cmd)
-			break;
-
-	if (scb == AHA274X_MAXSCB)
-		return(k_absent);
-
-	PAUSE_SEQUENCER(p);
-
-	/*
-	 *  This is the best case, really.  Check to see if the
-	 *  command is still in the sequencer's input queue.  If
-	 *  so, simply remove it.  Reload the queue afterward.
-	 */
-	queued = inb(O_QINCNT(p->base));
-	
-	for (i = found = 0; i < queued; i++) {
-		scbsave[i] = inb(O_QINFIFO(p->base));
-
-		if (scbsave[i] == scb) {
-			found = 1;
-			i -= 1;
-		}
-	}
-
-	queued -= found;
-	for (i = 0; i < queued; i++)
-		outb(scbsave[i], O_QINFIFO(p->base));
-
-	if (found)
-		goto complete;
-
-	/*
-	 *  Check the current SCB bank.  If it's not the one belonging
-	 *  to the command we want to kill, assume that the command
-	 *  is disconnected.  It's rather a pain to force a reconnect
-	 *  and send a message to the target, so we abdicate responsibility
-	 *  in this case.
-	 */
-	if (inb(O_SCBPTR(p->base)) != scb) {
-		if (unpause)
-			UNPAUSE_SEQUENCER(p);
-		return(k_disconnect);
-	}
-
-	/*
-	 *  Presumably at this point our target command is active.  Check
-	 *  to see if there's a message already in effect.  If not, place
-	 *  our message in and assert ATN so the target goes into MESSAGE
-	 *  OUT phase.
-	 */
-	if (inb(HA_MSG_FLAGS(p->base)) & 0x80) {
-		if (unpause)
-			UNPAUSE_SEQUENCER(p);
-		return(k_busy);
-	}
-
-	outb(0x80, HA_MSG_FLAGS(p->base));		/* active message */
-	outb(1, HA_MSG_LEN(p->base));			/* length = 1 */
-	outb(message, HA_MSG_START(p->base));		/* message body */
-
-	/*
-	 *  Assert ATN.  Use the value of SCSISIGO saved by the
-	 *  sequencer code so we don't alter its contents radically
-	 *  in the middle of something critical.
-	 */
-	outb(inb(HA_SIGSTATE(p->base)) | 0x10, O_SCSISIGO(p->base));
-
-	/*
-	 *  The command has been killed.  Do the bookkeeping, unpause
-	 *  the sequencer, and notify the higher-level SCSI code.
-	 */
-complete:
-	p->SCB_array[scb] = NULL;
-	if (unpause)
-		UNPAUSE_SEQUENCER(p);
-
-	cmd->result = result << 16;
-	cmd->scsi_done(cmd);
-	return(k_ok);
-}
-
-int aha274x_abort(Scsi_Cmnd *cmd)
-{
-	int rv;
-	long flags;
-
-	save_flags(flags);
-	cli();
-
-	switch (aha274x_kill(cmd, ABORT, DID_ABORT, !0)) {
-	    case k_ok:		rv = SCSI_ABORT_SUCCESS;	break;
-	    case k_busy:	rv = SCSI_ABORT_BUSY;		break;
-	    case k_absent:	rv = SCSI_ABORT_NOT_RUNNING;	break;
-	    case k_disconnect:	rv = SCSI_ABORT_SNOOZE;		break;
-	    default:
-		panic("aha274x_do_abort: internal error\n");
-	}
-
-	restore_flags(flags);
-	return(rv);
-}
-
-/*
- *  Resetting the bus always succeeds - is has to, otherwise the
- *  kernel will panic!  Try a surgical technique - sending a BUS
- *  DEVICE RESET message - on the offending target before pulling
- *  the SCSI bus reset line.
- */
-
-int aha274x_reset(Scsi_Cmnd *cmd)
-{
-	int i;
-	long flags;
-	Scsi_Cmnd *reset;
-	struct aha274x_host *p;
-
-	p = (struct aha274x_host *)cmd->host->hostdata;
-	save_flags(flags);
-	cli();
-
-	switch (aha274x_kill(cmd, BUS_DEVICE_RESET, DID_RESET, 0)) {
-
-	    case k_ok:
-		/*
-		 *  The RESET message was sent to the target
-		 *  with no problems.  Flag that target as
-		 *  needing a SDTR negotiation on the next
-		 *  connection and restart the sequencer.
-		 */
-		outb((1 << cmd->target), HA_NEEDSDTR(p->base));
-		UNPAUSE_SEQUENCER(p);
-		break;
-
-	    case k_absent:
-		/*
-		 *  The sequencer will not be paused if aha274x_kill()
-		 *  couldn't find the command.
-		 */
-		PAUSE_SEQUENCER(p);
-		/* falls through */
-
-	    case k_busy:
-	    case k_disconnect:
-		/*
-		 *  Do a hard reset of the SCSI bus.  According to the
-		 *  SCSI-2 draft specification, reset has to be asserted
-		 *  for at least 25us.  I'm invoking the kernel delay
-		 *  function for 30us since I'm not totally trusting of
-		 *  the busy loop timing.
-		 *
-		 *  XXX - I'm not convinced this works.  I tried resetting
-		 *	  the bus before, trying to get the devices on the
-		 *	  bus to revert to asynchronous transfer, and it
-		 *	  never seemed to work.
-		 */
-		debug("aha274x: attempting to reset scsi bus and card\n");
-
-		outb(1, O_SCSISEQ(p->base));		/* SCSIRSTO */
-		udelay(30);
-		outb(0, O_SCSISEQ(p->base));		/* !SCSIRSTO */
-
-		outb(0xff, HA_NEEDSDTR(p->base));
-		UNPAUSE_SEQUENCER(p);
-
-		/*
-		 *  Locate the command and return a "reset" status
-		 *  for it.  This is not completely correct and will
-		 *  probably return to haunt me later.
-		 */
-		for (i = 0; i < AHA274X_MAXSCB; i++) {
-			if (cmd == p->SCB_array[i]) {
-				reset = (Scsi_Cmnd *)p->SCB_array[i];
-				p->SCB_array[i] = NULL;
-				reset->result = DID_RESET << 16;
-				reset->scsi_done(reset);
-				break;
-			}
-		}
-		break;
-
-	    default:
-		panic("aha274x_reset: internal error\n");
-	}
-
-	restore_flags(flags);
-	return(SCSI_RESET_SUCCESS);
-}
-
-int aha274x_biosparam(Disk *disk, int devno, int geom[])
-{
-	int heads, sectors, cylinders;
-
-	/*
-	 *  XXX - if I could portably find the card's configuration
-	 *	  information, then this could be autodetected instead
-	 *	  of left to a boot-time switch.
-	 */
-	heads = 64;
-	sectors = 32;
-	cylinders = disk->capacity / (heads * sectors);
-
-	if (aha274x_extended && cylinders > 1024) {
-		heads = 255;
-		sectors = 63;
-		cylinders = disk->capacity / (255 * 63);
-	}
-
-	geom[0] = heads;
-	geom[1] = sectors;
-	geom[2] = cylinders;
-
-	return(0);
-}
-

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov with Sam's (original) version
of this