Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 2927 insertions, 0 deletions

diff --git a/kernel/drivers/scsi/atari_NCR5380.c b/kernel/drivers/scsi/atari_NCR5380.c
new file mode 100644
index 000000000..db87ece6e
--- /dev/null
+++ b/kernel/drivers/scsi/atari_NCR5380.c
@@ -0,0 +1,2927 @@
+/*
+ * NCR 5380 generic driver routines.  These should make it *trivial*
+ *	to implement 5380 SCSI drivers under Linux with a non-trantor
+ *	architecture.
+ *
+ *	Note that these routines also work with NR53c400 family chips.
+ *
+ * Copyright 1993, Drew Eckhardt
+ *	Visionary Computing
+ *	(Unix and Linux consulting and custom programming)
+ *	drew@colorado.edu
+ *	+1 (303) 666-5836
+ *
+ * For more information, please consult
+ *
+ * NCR 5380 Family
+ * SCSI Protocol Controller
+ * Databook
+ *
+ * NCR Microelectronics
+ * 1635 Aeroplaza Drive
+ * Colorado Springs, CO 80916
+ * 1+ (719) 578-3400
+ * 1+ (800) 334-5454
+ */
+
+/*
+ * ++roman: To port the 5380 driver to the Atari, I had to do some changes in
+ * this file, too:
+ *
+ *  - Some of the debug statements were incorrect (undefined variables and the
+ *    like). I fixed that.
+ *
+ *  - In information_transfer(), I think a #ifdef was wrong. Looking at the
+ *    possible DMA transfer size should also happen for REAL_DMA. I added this
+ *    in the #if statement.
+ *
+ *  - When using real DMA, information_transfer() should return in a DATAOUT
+ *    phase after starting the DMA. It has nothing more to do.
+ *
+ *  - The interrupt service routine should run main after end of DMA, too (not
+ *    only after RESELECTION interrupts). Additionally, it should _not_ test
+ *    for more interrupts after running main, since a DMA process may have
+ *    been started and interrupts are turned on now. The new int could happen
+ *    inside the execution of NCR5380_intr(), leading to recursive
+ *    calls.
+ *
+ *  - I've added a function merge_contiguous_buffers() that tries to
+ *    merge scatter-gather buffers that are located at contiguous
+ *    physical addresses and can be processed with the same DMA setup.
+ *    Since most scatter-gather operations work on a page (4K) of
+ *    4 buffers (1K), in more than 90% of all cases three interrupts and
+ *    DMA setup actions are saved.
+ *
+ * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA
+ *    and USLEEP, because these were messing up readability and will never be
+ *    needed for Atari SCSI.
+ *
+ * - I've revised the NCR5380_main() calling scheme (relax the 'main_running'
+ *   stuff), and 'main' is executed in a bottom half if awoken by an
+ *   interrupt.
+ *
+ * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..."
+ *   constructs. In my eyes, this made the source rather unreadable, so I
+ *   finally replaced that by the *_PRINTK() macros.
+ *
+ */
+
+/*
+ * Further development / testing that should be done :
+ * 1.  Test linked command handling code after Eric is ready with
+ *     the high level code.
+ */
+
+/* Adapted for the sun3 by Sam Creasey. */
+
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_transport_spi.h>
+
+#if (NDEBUG & NDEBUG_LISTS)
+#define LIST(x, y)						\
+	do {							\
+		printk("LINE:%d   Adding %p to %p\n",		\
+		       __LINE__, (void*)(x), (void*)(y));	\
+		if ((x) == (y))					\
+			udelay(5);				\
+	} while (0)
+#define REMOVE(w, x, y, z)					\
+	do {							\
+		printk("LINE:%d   Removing: %p->%p  %p->%p \n",	\
+		       __LINE__, (void*)(w), (void*)(x),	\
+		       (void*)(y), (void*)(z));			\
+		if ((x) == (y))					\
+			udelay(5);				\
+	} while (0)
+#else
+#define LIST(x,y)
+#define REMOVE(w,x,y,z)
+#endif
+
+#ifndef notyet
+#undef LINKED
+#endif
+
+/*
+ * Design
+ *
+ * This is a generic 5380 driver.  To use it on a different platform,
+ * one simply writes appropriate system specific macros (ie, data
+ * transfer - some PC's will use the I/O bus, 68K's must use
+ * memory mapped) and drops this file in their 'C' wrapper.
+ *
+ * As far as command queueing, two queues are maintained for
+ * each 5380 in the system - commands that haven't been issued yet,
+ * and commands that are currently executing.  This means that an
+ * unlimited number of commands may be queued, letting
+ * more commands propagate from the higher driver levels giving higher
+ * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported,
+ * allowing multiple commands to propagate all the way to a SCSI-II device
+ * while a command is already executing.
+ *
+ *
+ * Issues specific to the NCR5380 :
+ *
+ * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
+ * piece of hardware that requires you to sit in a loop polling for
+ * the REQ signal as long as you are connected.  Some devices are
+ * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
+ * while doing long seek operations.
+ *
+ * The workaround for this is to keep track of devices that have
+ * disconnected.  If the device hasn't disconnected, for commands that
+ * should disconnect, we do something like
+ *
+ * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
+ *
+ * Some tweaking of N and M needs to be done.  An algorithm based
+ * on "time to data" would give the best results as long as short time
+ * to datas (ie, on the same track) were considered, however these
+ * broken devices are the exception rather than the rule and I'd rather
+ * spend my time optimizing for the normal case.
+ *
+ * Architecture :
+ *
+ * At the heart of the design is a coroutine, NCR5380_main,
+ * which is started from a workqueue for each NCR5380 host in the
+ * system.  It attempts to establish I_T_L or I_T_L_Q nexuses by
+ * removing the commands from the issue queue and calling
+ * NCR5380_select() if a nexus is not established.
+ *
+ * Once a nexus is established, the NCR5380_information_transfer()
+ * phase goes through the various phases as instructed by the target.
+ * if the target goes into MSG IN and sends a DISCONNECT message,
+ * the command structure is placed into the per instance disconnected
+ * queue, and NCR5380_main tries to find more work.  If the target is
+ * idle for too long, the system will try to sleep.
+ *
+ * If a command has disconnected, eventually an interrupt will trigger,
+ * calling NCR5380_intr()  which will in turn call NCR5380_reselect
+ * to reestablish a nexus.  This will run main if necessary.
+ *
+ * On command termination, the done function will be called as
+ * appropriate.
+ *
+ * SCSI pointers are maintained in the SCp field of SCSI command
+ * structures, being initialized after the command is connected
+ * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
+ * Note that in violation of the standard, an implicit SAVE POINTERS operation
+ * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
+ */
+
+/*
+ * Using this file :
+ * This file a skeleton Linux SCSI driver for the NCR 5380 series
+ * of chips.  To use it, you write an architecture specific functions
+ * and macros and include this file in your driver.
+ *
+ * These macros control options :
+ * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
+ *	for commands that return with a CHECK CONDITION status.
+ *
+ * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
+ *	transceivers.
+ *
+ * LINKED - if defined, linked commands are supported.
+ *
+ * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
+ *
+ * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
+ *
+ * These macros MUST be defined :
+ *
+ * NCR5380_read(register)  - read from the specified register
+ *
+ * NCR5380_write(register, value) - write to the specific register
+ *
+ * NCR5380_implementation_fields  - additional fields needed for this
+ *      specific implementation of the NCR5380
+ *
+ * Either real DMA *or* pseudo DMA may be implemented
+ * REAL functions :
+ * NCR5380_REAL_DMA should be defined if real DMA is to be used.
+ * Note that the DMA setup functions should return the number of bytes
+ *	that they were able to program the controller for.
+ *
+ * Also note that generic i386/PC versions of these macros are
+ *	available as NCR5380_i386_dma_write_setup,
+ *	NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
+ *
+ * NCR5380_dma_write_setup(instance, src, count) - initialize
+ * NCR5380_dma_read_setup(instance, dst, count) - initialize
+ * NCR5380_dma_residual(instance); - residual count
+ *
+ * PSEUDO functions :
+ * NCR5380_pwrite(instance, src, count)
+ * NCR5380_pread(instance, dst, count);
+ *
+ * The generic driver is initialized by calling NCR5380_init(instance),
+ * after setting the appropriate host specific fields and ID.  If the
+ * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
+ * possible) function may be used.
+ */
+
+/* Macros ease life... :-) */
+#define	SETUP_HOSTDATA(in)				\
+    struct NCR5380_hostdata *hostdata =			\
+	(struct NCR5380_hostdata *)(in)->hostdata
+#define	HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)
+
+#define	NEXT(cmd)		((struct scsi_cmnd *)(cmd)->host_scribble)
+#define	SET_NEXT(cmd,next)	((cmd)->host_scribble = (void *)(next))
+#define	NEXTADDR(cmd)		((struct scsi_cmnd **)&(cmd)->host_scribble)
+
+#define	HOSTNO		instance->host_no
+#define	H_NO(cmd)	(cmd)->device->host->host_no
+
+#ifdef SUPPORT_TAGS
+
+/*
+ * Functions for handling tagged queuing
+ * =====================================
+ *
+ * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
+ *
+ * Using consecutive numbers for the tags is no good idea in my eyes. There
+ * could be wrong re-usings if the counter (8 bit!) wraps and some early
+ * command has been preempted for a long time. My solution: a bitfield for
+ * remembering used tags.
+ *
+ * There's also the problem that each target has a certain queue size, but we
+ * cannot know it in advance :-( We just see a QUEUE_FULL status being
+ * returned. So, in this case, the driver internal queue size assumption is
+ * reduced to the number of active tags if QUEUE_FULL is returned by the
+ * target. The command is returned to the mid-level, but with status changed
+ * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL
+ * correctly.
+ *
+ * We're also not allowed running tagged commands as long as an untagged
+ * command is active. And REQUEST SENSE commands after a contingent allegiance
+ * condition _must_ be untagged. To keep track whether an untagged command has
+ * been issued, the host->busy array is still employed, as it is without
+ * support for tagged queuing.
+ *
+ * One could suspect that there are possible race conditions between
+ * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
+ * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
+ * which already guaranteed to be running at most once. It is also the only
+ * place where tags/LUNs are allocated. So no other allocation can slip
+ * between that pair, there could only happen a reselection, which can free a
+ * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
+ * important: the tag bit must be cleared before 'nr_allocated' is decreased.
+ */
+
+static void __init init_tags(struct NCR5380_hostdata *hostdata)
+{
+	int target, lun;
+	struct tag_alloc *ta;
+
+	if (!(hostdata->flags & FLAG_TAGGED_QUEUING))
+		return;
+
+	for (target = 0; target < 8; ++target) {
+		for (lun = 0; lun < 8; ++lun) {
+			ta = &hostdata->TagAlloc[target][lun];
+			bitmap_zero(ta->allocated, MAX_TAGS);
+			ta->nr_allocated = 0;
+			/* At the beginning, assume the maximum queue size we could
+			 * support (MAX_TAGS). This value will be decreased if the target
+			 * returns QUEUE_FULL status.
+			 */
+			ta->queue_size = MAX_TAGS;
+		}
+	}
+}
+
+
+/* Check if we can issue a command to this LUN: First see if the LUN is marked
+ * busy by an untagged command. If the command should use tagged queuing, also
+ * check that there is a free tag and the target's queue won't overflow. This
+ * function should be called with interrupts disabled to avoid race
+ * conditions.
+ */
+
+static int is_lun_busy(struct scsi_cmnd *cmd, int should_be_tagged)
+{
+	u8 lun = cmd->device->lun;
+	SETUP_HOSTDATA(cmd->device->host);
+
+	if (hostdata->busy[cmd->device->id] & (1 << lun))
+		return 1;
+	if (!should_be_tagged ||
+	    !(hostdata->flags & FLAG_TAGGED_QUEUING) ||
+	    !cmd->device->tagged_supported)
+		return 0;
+	if (hostdata->TagAlloc[scmd_id(cmd)][lun].nr_allocated >=
+	    hostdata->TagAlloc[scmd_id(cmd)][lun].queue_size) {
+		dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d: no free tags\n",
+			   H_NO(cmd), cmd->device->id, lun);
+		return 1;
+	}
+	return 0;
+}
+
+
+/* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
+ * must be called before!), or reserve the LUN in 'busy' if the command is
+ * untagged.
+ */
+
+static void cmd_get_tag(struct scsi_cmnd *cmd, int should_be_tagged)
+{
+	u8 lun = cmd->device->lun;
+	SETUP_HOSTDATA(cmd->device->host);
+
+	/* If we or the target don't support tagged queuing, allocate the LUN for
+	 * an untagged command.
+	 */
+	if (!should_be_tagged ||
+	    !(hostdata->flags & FLAG_TAGGED_QUEUING) ||
+	    !cmd->device->tagged_supported) {
+		cmd->tag = TAG_NONE;
+		hostdata->busy[cmd->device->id] |= (1 << lun);
+		dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d now allocated by untagged "
+			   "command\n", H_NO(cmd), cmd->device->id, lun);
+	} else {
+		struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun];
+
+		cmd->tag = find_first_zero_bit(ta->allocated, MAX_TAGS);
+		set_bit(cmd->tag, ta->allocated);
+		ta->nr_allocated++;
+		dprintk(NDEBUG_TAGS, "scsi%d: using tag %d for target %d lun %d "
+			   "(now %d tags in use)\n",
+			   H_NO(cmd), cmd->tag, cmd->device->id,
+			   lun, ta->nr_allocated);
+	}
+}
+
+
+/* Mark the tag of command 'cmd' as free, or in case of an untagged command,
+ * unlock the LUN.
+ */
+
+static void cmd_free_tag(struct scsi_cmnd *cmd)
+{
+	u8 lun = cmd->device->lun;
+	SETUP_HOSTDATA(cmd->device->host);
+
+	if (cmd->tag == TAG_NONE) {
+		hostdata->busy[cmd->device->id] &= ~(1 << lun);
+		dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d untagged cmd finished\n",
+			   H_NO(cmd), cmd->device->id, lun);
+	} else if (cmd->tag >= MAX_TAGS) {
+		printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n",
+		       H_NO(cmd), cmd->tag);
+	} else {
+		struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun];
+		clear_bit(cmd->tag, ta->allocated);
+		ta->nr_allocated--;
+		dprintk(NDEBUG_TAGS, "scsi%d: freed tag %d for target %d lun %d\n",
+			   H_NO(cmd), cmd->tag, cmd->device->id, lun);
+	}
+}
+
+
+static void free_all_tags(struct NCR5380_hostdata *hostdata)
+{
+	int target, lun;
+	struct tag_alloc *ta;
+
+	if (!(hostdata->flags & FLAG_TAGGED_QUEUING))
+		return;
+
+	for (target = 0; target < 8; ++target) {
+		for (lun = 0; lun < 8; ++lun) {
+			ta = &hostdata->TagAlloc[target][lun];
+			bitmap_zero(ta->allocated, MAX_TAGS);
+			ta->nr_allocated = 0;
+		}
+	}
+}
+
+#endif /* SUPPORT_TAGS */
+
+
+/*
+ * Function: void merge_contiguous_buffers( struct scsi_cmnd *cmd )
+ *
+ * Purpose: Try to merge several scatter-gather requests into one DMA
+ *    transfer. This is possible if the scatter buffers lie on
+ *    physical contiguous addresses.
+ *
+ * Parameters: struct scsi_cmnd *cmd
+ *    The command to work on. The first scatter buffer's data are
+ *    assumed to be already transferred into ptr/this_residual.
+ */
+
+static void merge_contiguous_buffers(struct scsi_cmnd *cmd)
+{
+#if !defined(CONFIG_SUN3)
+	unsigned long endaddr;
+#if (NDEBUG & NDEBUG_MERGING)
+	unsigned long oldlen = cmd->SCp.this_residual;
+	int cnt = 1;
+#endif
+
+	for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
+	     cmd->SCp.buffers_residual &&
+	     virt_to_phys(sg_virt(&cmd->SCp.buffer[1])) == endaddr;) {
+		dprintk(NDEBUG_MERGING, "VTOP(%p) == %08lx -> merging\n",
+			   page_address(sg_page(&cmd->SCp.buffer[1])), endaddr);
+#if (NDEBUG & NDEBUG_MERGING)
+		++cnt;
+#endif
+		++cmd->SCp.buffer;
+		--cmd->SCp.buffers_residual;
+		cmd->SCp.this_residual += cmd->SCp.buffer->length;
+		endaddr += cmd->SCp.buffer->length;
+	}
+#if (NDEBUG & NDEBUG_MERGING)
+	if (oldlen != cmd->SCp.this_residual)
+		dprintk(NDEBUG_MERGING, "merged %d buffers from %p, new length %08x\n",
+			   cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
+#endif
+#endif /* !defined(CONFIG_SUN3) */
+}
+
+/**
+ * initialize_SCp - init the scsi pointer field
+ * @cmd: command block to set up
+ *
+ * Set up the internal fields in the SCSI command.
+ */
+
+static inline void initialize_SCp(struct scsi_cmnd *cmd)
+{
+	/*
+	 * Initialize the Scsi Pointer field so that all of the commands in the
+	 * various queues are valid.
+	 */
+
+	if (scsi_bufflen(cmd)) {
+		cmd->SCp.buffer = scsi_sglist(cmd);
+		cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
+		cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
+		cmd->SCp.this_residual = cmd->SCp.buffer->length;
+		/* ++roman: Try to merge some scatter-buffers if they are at
+		 * contiguous physical addresses.
+		 */
+		merge_contiguous_buffers(cmd);
+	} else {
+		cmd->SCp.buffer = NULL;
+		cmd->SCp.buffers_residual = 0;
+		cmd->SCp.ptr = NULL;
+		cmd->SCp.this_residual = 0;
+	}
+}
+
+#include <linux/delay.h>
+
+#if NDEBUG
+static struct {
+	unsigned char mask;
+	const char *name;
+} signals[] = {
+	{ SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" },
+	{ SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD,  "CD" }, { SR_IO, "IO" },
+	{ SR_SEL, "SEL" }, {0, NULL}
+}, basrs[] = {
+	{BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}
+}, icrs[] = {
+	{ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"},
+	{ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"},
+	{ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"},
+	{0, NULL}
+}, mrs[] = {
+	{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"},
+	{MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR,
+	"MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"},
+	{MR_MONITOR_BSY, "MODE MONITOR BSY"},
+	{MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"},
+	{0, NULL}
+};
+
+/**
+ * NCR5380_print - print scsi bus signals
+ * @instance: adapter state to dump
+ *
+ * Print the SCSI bus signals for debugging purposes
+ */
+
+static void NCR5380_print(struct Scsi_Host *instance)
+{
+	unsigned char status, data, basr, mr, icr, i;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	data = NCR5380_read(CURRENT_SCSI_DATA_REG);
+	status = NCR5380_read(STATUS_REG);
+	mr = NCR5380_read(MODE_REG);
+	icr = NCR5380_read(INITIATOR_COMMAND_REG);
+	basr = NCR5380_read(BUS_AND_STATUS_REG);
+	local_irq_restore(flags);
+	printk("STATUS_REG: %02x ", status);
+	for (i = 0; signals[i].mask; ++i)
+		if (status & signals[i].mask)
+			printk(",%s", signals[i].name);
+	printk("\nBASR: %02x ", basr);
+	for (i = 0; basrs[i].mask; ++i)
+		if (basr & basrs[i].mask)
+			printk(",%s", basrs[i].name);
+	printk("\nICR: %02x ", icr);
+	for (i = 0; icrs[i].mask; ++i)
+		if (icr & icrs[i].mask)
+			printk(",%s", icrs[i].name);
+	printk("\nMODE: %02x ", mr);
+	for (i = 0; mrs[i].mask; ++i)
+		if (mr & mrs[i].mask)
+			printk(",%s", mrs[i].name);
+	printk("\n");
+}
+
+static struct {
+	unsigned char value;
+	const char *name;
+} phases[] = {
+	{PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
+	{PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
+	{PHASE_UNKNOWN, "UNKNOWN"}
+};
+
+/**
+ * NCR5380_print_phase - show SCSI phase
+ * @instance: adapter to dump
+ *
+ * Print the current SCSI phase for debugging purposes
+ *
+ * Locks: none
+ */
+
+static void NCR5380_print_phase(struct Scsi_Host *instance)
+{
+	unsigned char status;
+	int i;
+
+	status = NCR5380_read(STATUS_REG);
+	if (!(status & SR_REQ))
+		printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO);
+	else {
+		for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
+		     (phases[i].value != (status & PHASE_MASK)); ++i)
+			;
+		printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name);
+	}
+}
+
+#endif
+
+/*
+ * ++roman: New scheme of calling NCR5380_main()
+ *
+ * If we're not in an interrupt, we can call our main directly, it cannot be
+ * already running. Else, we queue it on a task queue, if not 'main_running'
+ * tells us that a lower level is already executing it. This way,
+ * 'main_running' needs not be protected in a special way.
+ *
+ * queue_main() is a utility function for putting our main onto the task
+ * queue, if main_running is false. It should be called only from a
+ * interrupt or bottom half.
+ */
+
+#include <linux/gfp.h>
+#include <linux/workqueue.h>
+#include <linux/interrupt.h>
+
+static inline void queue_main(struct NCR5380_hostdata *hostdata)
+{
+	if (!hostdata->main_running) {
+		/* If in interrupt and NCR5380_main() not already running,
+		   queue it on the 'immediate' task queue, to be processed
+		   immediately after the current interrupt processing has
+		   finished. */
+		schedule_work(&hostdata->main_task);
+	}
+	/* else: nothing to do: the running NCR5380_main() will pick up
+	   any newly queued command. */
+}
+
+/**
+ * NCR58380_info - report driver and host information
+ * @instance: relevant scsi host instance
+ *
+ * For use as the host template info() handler.
+ *
+ * Locks: none
+ */
+
+static const char *NCR5380_info(struct Scsi_Host *instance)
+{
+	struct NCR5380_hostdata *hostdata = shost_priv(instance);
+
+	return hostdata->info;
+}
+
+static void prepare_info(struct Scsi_Host *instance)
+{
+	struct NCR5380_hostdata *hostdata = shost_priv(instance);
+
+	snprintf(hostdata->info, sizeof(hostdata->info),
+	         "%s, io_port 0x%lx, n_io_port %d, "
+	         "base 0x%lx, irq %d, "
+	         "can_queue %d, cmd_per_lun %d, "
+	         "sg_tablesize %d, this_id %d, "
+	         "flags { %s}, "
+	         "options { %s} ",
+	         instance->hostt->name, instance->io_port, instance->n_io_port,
+	         instance->base, instance->irq,
+	         instance->can_queue, instance->cmd_per_lun,
+	         instance->sg_tablesize, instance->this_id,
+	         hostdata->flags & FLAG_TAGGED_QUEUING ? "TAGGED_QUEUING " : "",
+#ifdef DIFFERENTIAL
+	         "DIFFERENTIAL "
+#endif
+#ifdef REAL_DMA
+	         "REAL_DMA "
+#endif
+#ifdef PARITY
+	         "PARITY "
+#endif
+#ifdef SUPPORT_TAGS
+	         "SUPPORT_TAGS "
+#endif
+	         "");
+}
+
+/**
+ * NCR5380_print_status - dump controller info
+ * @instance: controller to dump
+ *
+ * Print commands in the various queues, called from NCR5380_abort
+ * to aid debugging.
+ */
+
+static void lprint_Scsi_Cmnd(struct scsi_cmnd *cmd)
+{
+	int i, s;
+	unsigned char *command;
+	printk("scsi%d: destination target %d, lun %llu\n",
+		H_NO(cmd), cmd->device->id, cmd->device->lun);
+	printk(KERN_CONT "        command = ");
+	command = cmd->cmnd;
+	printk(KERN_CONT "%2d (0x%02x)", command[0], command[0]);
+	for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
+		printk(KERN_CONT " %02x", command[i]);
+	printk("\n");
+}
+
+static void NCR5380_print_status(struct Scsi_Host *instance)
+{
+	struct NCR5380_hostdata *hostdata;
+	struct scsi_cmnd *ptr;
+	unsigned long flags;
+
+	NCR5380_dprint(NDEBUG_ANY, instance);
+	NCR5380_dprint_phase(NDEBUG_ANY, instance);
+
+	hostdata = (struct NCR5380_hostdata *)instance->hostdata;
+
+	local_irq_save(flags);
+	printk("NCR5380: coroutine is%s running.\n",
+		hostdata->main_running ? "" : "n't");
+	if (!hostdata->connected)
+		printk("scsi%d: no currently connected command\n", HOSTNO);
+	else
+		lprint_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected);
+	printk("scsi%d: issue_queue\n", HOSTNO);
+	for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr))
+		lprint_Scsi_Cmnd(ptr);
+
+	printk("scsi%d: disconnected_queue\n", HOSTNO);
+	for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr;
+	     ptr = NEXT(ptr))
+		lprint_Scsi_Cmnd(ptr);
+
+	local_irq_restore(flags);
+	printk("\n");
+}
+
+static void show_Scsi_Cmnd(struct scsi_cmnd *cmd, struct seq_file *m)
+{
+	int i, s;
+	unsigned char *command;
+	seq_printf(m, "scsi%d: destination target %d, lun %llu\n",
+		H_NO(cmd), cmd->device->id, cmd->device->lun);
+	seq_puts(m, "        command = ");
+	command = cmd->cmnd;
+	seq_printf(m, "%2d (0x%02x)", command[0], command[0]);
+	for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
+		seq_printf(m, " %02x", command[i]);
+	seq_putc(m, '\n');
+}
+
+static int __maybe_unused NCR5380_show_info(struct seq_file *m,
+                                            struct Scsi_Host *instance)
+{
+	struct NCR5380_hostdata *hostdata;
+	struct scsi_cmnd *ptr;
+	unsigned long flags;
+
+	hostdata = (struct NCR5380_hostdata *)instance->hostdata;
+
+	local_irq_save(flags);
+	seq_printf(m, "NCR5380: coroutine is%s running.\n",
+		hostdata->main_running ? "" : "n't");
+	if (!hostdata->connected)
+		seq_printf(m, "scsi%d: no currently connected command\n", HOSTNO);
+	else
+		show_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected, m);
+	seq_printf(m, "scsi%d: issue_queue\n", HOSTNO);
+	for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr))
+		show_Scsi_Cmnd(ptr, m);
+
+	seq_printf(m, "scsi%d: disconnected_queue\n", HOSTNO);
+	for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr;
+	     ptr = NEXT(ptr))
+		show_Scsi_Cmnd(ptr, m);
+
+	local_irq_restore(flags);
+	return 0;
+}
+
+/**
+ * NCR5380_init - initialise an NCR5380
+ * @instance: adapter to configure
+ * @flags: control flags
+ *
+ * Initializes *instance and corresponding 5380 chip,
+ * with flags OR'd into the initial flags value.
+ *
+ * Notes : I assume that the host, hostno, and id bits have been
+ * set correctly. I don't care about the irq and other fields.
+ *
+ * Returns 0 for success
+ */
+
+static int __init NCR5380_init(struct Scsi_Host *instance, int flags)
+{
+	int i;
+	SETUP_HOSTDATA(instance);
+
+	hostdata->host = instance;
+	hostdata->aborted = 0;
+	hostdata->id_mask = 1 << instance->this_id;
+	hostdata->id_higher_mask = 0;
+	for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
+		if (i > hostdata->id_mask)
+			hostdata->id_higher_mask |= i;
+	for (i = 0; i < 8; ++i)
+		hostdata->busy[i] = 0;
+#ifdef SUPPORT_TAGS
+	init_tags(hostdata);
+#endif
+#if defined (REAL_DMA)
+	hostdata->dma_len = 0;
+#endif
+	hostdata->targets_present = 0;
+	hostdata->connected = NULL;
+	hostdata->issue_queue = NULL;
+	hostdata->disconnected_queue = NULL;
+	hostdata->flags = flags;
+
+	INIT_WORK(&hostdata->main_task, NCR5380_main);
+
+	prepare_info(instance);
+
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+	NCR5380_write(MODE_REG, MR_BASE);
+	NCR5380_write(TARGET_COMMAND_REG, 0);
+	NCR5380_write(SELECT_ENABLE_REG, 0);
+
+	return 0;
+}
+
+/**
+ * NCR5380_exit - remove an NCR5380
+ * @instance: adapter to remove
+ *
+ * Assumes that no more work can be queued (e.g. by NCR5380_intr).
+ */
+
+static void NCR5380_exit(struct Scsi_Host *instance)
+{
+	struct NCR5380_hostdata *hostdata = shost_priv(instance);
+
+	cancel_work_sync(&hostdata->main_task);
+}
+
+/**
+ * NCR5380_queue_command - queue a command
+ * @instance: the relevant SCSI adapter
+ * @cmd: SCSI command
+ *
+ * cmd is added to the per instance issue_queue, with minor
+ * twiddling done to the host specific fields of cmd.  If the
+ * main coroutine is not running, it is restarted.
+ */
+
+static int NCR5380_queue_command(struct Scsi_Host *instance,
+                                 struct scsi_cmnd *cmd)
+{
+	struct NCR5380_hostdata *hostdata = shost_priv(instance);
+	struct scsi_cmnd *tmp;
+	unsigned long flags;
+
+#if (NDEBUG & NDEBUG_NO_WRITE)
+	switch (cmd->cmnd[0]) {
+	case WRITE_6:
+	case WRITE_10:
+		printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
+		       H_NO(cmd));
+		cmd->result = (DID_ERROR << 16);
+		cmd->scsi_done(cmd);
+		return 0;
+	}
+#endif /* (NDEBUG & NDEBUG_NO_WRITE) */
+
+	/*
+	 * We use the host_scribble field as a pointer to the next command
+	 * in a queue
+	 */
+
+	SET_NEXT(cmd, NULL);
+	cmd->result = 0;
+
+	/*
+	 * Insert the cmd into the issue queue. Note that REQUEST SENSE
+	 * commands are added to the head of the queue since any command will
+	 * clear the contingent allegiance condition that exists and the
+	 * sense data is only guaranteed to be valid while the condition exists.
+	 */
+
+	/* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
+	 * Otherwise a running NCR5380_main may steal the lock.
+	 * Lock before actually inserting due to fairness reasons explained in
+	 * atari_scsi.c. If we insert first, then it's impossible for this driver
+	 * to release the lock.
+	 * Stop timer for this command while waiting for the lock, or timeouts
+	 * may happen (and they really do), and it's no good if the command doesn't
+	 * appear in any of the queues.
+	 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
+	 * because also a timer int can trigger an abort or reset, which would
+	 * alter queues and touch the lock.
+	 */
+	if (!NCR5380_acquire_dma_irq(instance))
+		return SCSI_MLQUEUE_HOST_BUSY;
+
+	local_irq_save(flags);
+
+	/*
+	 * Insert the cmd into the issue queue. Note that REQUEST SENSE
+	 * commands are added to the head of the queue since any command will
+	 * clear the contingent allegiance condition that exists and the
+	 * sense data is only guaranteed to be valid while the condition exists.
+	 */
+
+	if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
+		LIST(cmd, hostdata->issue_queue);
+		SET_NEXT(cmd, hostdata->issue_queue);
+		hostdata->issue_queue = cmd;
+	} else {
+		for (tmp = (struct scsi_cmnd *)hostdata->issue_queue;
+		     NEXT(tmp); tmp = NEXT(tmp))
+			;
+		LIST(cmd, tmp);
+		SET_NEXT(tmp, cmd);
+	}
+	local_irq_restore(flags);
+
+	dprintk(NDEBUG_QUEUES, "scsi%d: command added to %s of queue\n", H_NO(cmd),
+		  (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
+
+	/* If queue_command() is called from an interrupt (real one or bottom
+	 * half), we let queue_main() do the job of taking care about main. If it
+	 * is already running, this is a no-op, else main will be queued.
+	 *
+	 * If we're not in an interrupt, we can call NCR5380_main()
+	 * unconditionally, because it cannot be already running.
+	 */
+	if (in_interrupt() || irqs_disabled())
+		queue_main(hostdata);
+	else
+		NCR5380_main(&hostdata->main_task);
+	return 0;
+}
+
+static inline void maybe_release_dma_irq(struct Scsi_Host *instance)
+{
+	struct NCR5380_hostdata *hostdata = shost_priv(instance);
+
+	/* Caller does the locking needed to set & test these data atomically */
+	if (!hostdata->disconnected_queue &&
+	    !hostdata->issue_queue &&
+	    !hostdata->connected &&
+	    !hostdata->retain_dma_intr)
+		NCR5380_release_dma_irq(instance);
+}
+
+/**
+ * NCR5380_main - NCR state machines
+ *
+ * NCR5380_main is a coroutine that runs as long as more work can
+ * be done on the NCR5380 host adapters in a system.  Both
+ * NCR5380_queue_command() and NCR5380_intr() will try to start it
+ * in case it is not running.
+ *
+ * Locks: called as its own thread with no locks held.
+ */
+
+static void NCR5380_main(struct work_struct *work)
+{
+	struct NCR5380_hostdata *hostdata =
+		container_of(work, struct NCR5380_hostdata, main_task);
+	struct Scsi_Host *instance = hostdata->host;
+	struct scsi_cmnd *tmp, *prev;
+	int done;
+	unsigned long flags;
+
+	/*
+	 * We run (with interrupts disabled) until we're sure that none of
+	 * the host adapters have anything that can be done, at which point
+	 * we set main_running to 0 and exit.
+	 *
+	 * Interrupts are enabled before doing various other internal
+	 * instructions, after we've decided that we need to run through
+	 * the loop again.
+	 *
+	 * this should prevent any race conditions.
+	 *
+	 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
+	 * because also a timer int can trigger an abort or reset, which can
+	 * alter queues and touch the Falcon lock.
+	 */
+
+	/* Tell int handlers main() is now already executing.  Note that
+	   no races are possible here. If an int comes in before
+	   'main_running' is set here, and queues/executes main via the
+	   task queue, it doesn't do any harm, just this instance of main
+	   won't find any work left to do. */
+	if (hostdata->main_running)
+		return;
+	hostdata->main_running = 1;
+
+	local_save_flags(flags);
+	do {
+		local_irq_disable();	/* Freeze request queues */
+		done = 1;
+
+		if (!hostdata->connected) {
+			dprintk(NDEBUG_MAIN, "scsi%d: not connected\n", HOSTNO);
+			/*
+			 * Search through the issue_queue for a command destined
+			 * for a target that's not busy.
+			 */
+#if (NDEBUG & NDEBUG_LISTS)
+			for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, prev = NULL;
+			     tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
+				;
+			/*printk("%p  ", tmp);*/
+			if ((tmp == prev) && tmp)
+				printk(" LOOP\n");
+			/* else printk("\n"); */
+#endif
+			for (tmp = (struct scsi_cmnd *) hostdata->issue_queue,
+			     prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) {
+				u8 lun = tmp->device->lun;
+
+				dprintk(NDEBUG_LISTS,
+				        "MAIN tmp=%p target=%d busy=%d lun=%d\n",
+				        tmp, scmd_id(tmp), hostdata->busy[scmd_id(tmp)],
+				        lun);
+				/*  When we find one, remove it from the issue queue. */
+				/* ++guenther: possible race with Falcon locking */
+				if (
+#ifdef SUPPORT_TAGS
+				    !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
+#else
+				    !(hostdata->busy[tmp->device->id] & (1 << lun))
+#endif
+				    ) {
+					/* ++guenther: just to be sure, this must be atomic */
+					local_irq_disable();
+					if (prev) {
+						REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
+						SET_NEXT(prev, NEXT(tmp));
+					} else {
+						REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
+						hostdata->issue_queue = NEXT(tmp);
+					}
+					SET_NEXT(tmp, NULL);
+					hostdata->retain_dma_intr++;
+
+					/* reenable interrupts after finding one */
+					local_irq_restore(flags);
+
+					/*
+					 * Attempt to establish an I_T_L nexus here.
+					 * On success, instance->hostdata->connected is set.
+					 * On failure, we must add the command back to the
+					 *   issue queue so we can keep trying.
+					 */
+					dprintk(NDEBUG_MAIN, "scsi%d: main(): command for target %d "
+						    "lun %d removed from issue_queue\n",
+						    HOSTNO, tmp->device->id, lun);
+					/*
+					 * REQUEST SENSE commands are issued without tagged
+					 * queueing, even on SCSI-II devices because the
+					 * contingent allegiance condition exists for the
+					 * entire unit.
+					 */
+					/* ++roman: ...and the standard also requires that
+					 * REQUEST SENSE command are untagged.
+					 */
+
+#ifdef SUPPORT_TAGS
+					cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE);
+#endif
+					if (!NCR5380_select(instance, tmp)) {
+						local_irq_disable();
+						hostdata->retain_dma_intr--;
+						/* release if target did not response! */
+						maybe_release_dma_irq(instance);
+						local_irq_restore(flags);
+						break;
+					} else {
+						local_irq_disable();
+						LIST(tmp, hostdata->issue_queue);
+						SET_NEXT(tmp, hostdata->issue_queue);
+						hostdata->issue_queue = tmp;
+#ifdef SUPPORT_TAGS
+						cmd_free_tag(tmp);
+#endif
+						hostdata->retain_dma_intr--;
+						local_irq_restore(flags);
+						dprintk(NDEBUG_MAIN, "scsi%d: main(): select() failed, "
+							    "returned to issue_queue\n", HOSTNO);
+						if (hostdata->connected)
+							break;
+					}
+				} /* if target/lun/target queue is not busy */
+			} /* for issue_queue */
+		} /* if (!hostdata->connected) */
+
+		if (hostdata->connected
+#ifdef REAL_DMA
+		    && !hostdata->dma_len
+#endif
+		    ) {
+			local_irq_restore(flags);
+			dprintk(NDEBUG_MAIN, "scsi%d: main: performing information transfer\n",
+				    HOSTNO);
+			NCR5380_information_transfer(instance);
+			dprintk(NDEBUG_MAIN, "scsi%d: main: done set false\n", HOSTNO);
+			done = 0;
+		}
+	} while (!done);
+
+	/* Better allow ints _after_ 'main_running' has been cleared, else
+	   an interrupt could believe we'll pick up the work it left for
+	   us, but we won't see it anymore here... */
+	hostdata->main_running = 0;
+	local_irq_restore(flags);
+}
+
+
+#ifdef REAL_DMA
+/*
+ * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
+ *
+ * Purpose : Called by interrupt handler when DMA finishes or a phase
+ *	mismatch occurs (which would finish the DMA transfer).
+ *
+ * Inputs : instance - this instance of the NCR5380.
+ *
+ */
+
+static void NCR5380_dma_complete(struct Scsi_Host *instance)
+{
+	SETUP_HOSTDATA(instance);
+	int transferred;
+	unsigned char **data;
+	volatile int *count;
+	int saved_data = 0, overrun = 0;
+	unsigned char p;
+
+	if (!hostdata->connected) {
+		printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
+		       "no connected cmd\n", HOSTNO);
+		return;
+	}
+
+	if (hostdata->read_overruns) {
+		p = hostdata->connected->SCp.phase;
+		if (p & SR_IO) {
+			udelay(10);
+			if ((NCR5380_read(BUS_AND_STATUS_REG) &
+			     (BASR_PHASE_MATCH|BASR_ACK)) ==
+			    (BASR_PHASE_MATCH|BASR_ACK)) {
+				saved_data = NCR5380_read(INPUT_DATA_REG);
+				overrun = 1;
+				dprintk(NDEBUG_DMA, "scsi%d: read overrun handled\n", HOSTNO);
+			}
+		}
+	}
+
+	dprintk(NDEBUG_DMA, "scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
+		   HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
+		   NCR5380_read(STATUS_REG));
+
+#if defined(CONFIG_SUN3)
+	if ((sun3scsi_dma_finish(rq_data_dir(hostdata->connected->request)))) {
+		pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n",
+		       instance->host_no);
+		BUG();
+	}
+
+	/* make sure we're not stuck in a data phase */
+	if ((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) ==
+	    (BASR_PHASE_MATCH | BASR_ACK)) {
+		pr_err("scsi%d: BASR %02x\n", instance->host_no,
+		       NCR5380_read(BUS_AND_STATUS_REG));
+		pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n",
+		       instance->host_no);
+		BUG();
+	}
+#endif
+
+	(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
+	NCR5380_write(MODE_REG, MR_BASE);
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+
+	transferred = hostdata->dma_len - NCR5380_dma_residual(instance);
+	hostdata->dma_len = 0;
+
+	data = (unsigned char **)&hostdata->connected->SCp.ptr;
+	count = &hostdata->connected->SCp.this_residual;
+	*data += transferred;
+	*count -= transferred;
+
+	if (hostdata->read_overruns) {
+		int cnt, toPIO;
+
+		if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
+			cnt = toPIO = hostdata->read_overruns;
+			if (overrun) {
+				dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n");
+				*(*data)++ = saved_data;
+				(*count)--;
+				cnt--;
+				toPIO--;
+			}
+			dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
+			NCR5380_transfer_pio(instance, &p, &cnt, data);
+			*count -= toPIO - cnt;
+		}
+	}
+}
+#endif /* REAL_DMA */
+
+
+/**
+ * NCR5380_intr - generic NCR5380 irq handler
+ * @irq: interrupt number
+ * @dev_id: device info
+ *
+ * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
+ * from the disconnected queue, and restarting NCR5380_main()
+ * as required.
+ */
+
+static irqreturn_t NCR5380_intr(int irq, void *dev_id)
+{
+	struct Scsi_Host *instance = dev_id;
+	int done = 1, handled = 0;
+	unsigned char basr;
+
+	dprintk(NDEBUG_INTR, "scsi%d: NCR5380 irq triggered\n", HOSTNO);
+
+	/* Look for pending interrupts */
+	basr = NCR5380_read(BUS_AND_STATUS_REG);
+	dprintk(NDEBUG_INTR, "scsi%d: BASR=%02x\n", HOSTNO, basr);
+	/* dispatch to appropriate routine if found and done=0 */
+	if (basr & BASR_IRQ) {
+		NCR5380_dprint(NDEBUG_INTR, instance);
+		if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
+			done = 0;
+			dprintk(NDEBUG_INTR, "scsi%d: SEL interrupt\n", HOSTNO);
+			NCR5380_reselect(instance);
+			(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
+		} else if (basr & BASR_PARITY_ERROR) {
+			dprintk(NDEBUG_INTR, "scsi%d: PARITY interrupt\n", HOSTNO);
+			(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
+		} else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
+			dprintk(NDEBUG_INTR, "scsi%d: RESET interrupt\n", HOSTNO);
+			(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
+		} else {
+			/*
+			 * The rest of the interrupt conditions can occur only during a
+			 * DMA transfer
+			 */
+
+#if defined(REAL_DMA)
+			/*
+			 * We should only get PHASE MISMATCH and EOP interrupts if we have
+			 * DMA enabled, so do a sanity check based on the current setting
+			 * of the MODE register.
+			 */
+
+			if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
+			    ((basr & BASR_END_DMA_TRANSFER) ||
+			     !(basr & BASR_PHASE_MATCH))) {
+
+				dprintk(NDEBUG_INTR, "scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
+				NCR5380_dma_complete( instance );
+				done = 0;
+			} else
+#endif /* REAL_DMA */
+			{
+/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
+				if (basr & BASR_PHASE_MATCH)
+					dprintk(NDEBUG_INTR, "scsi%d: unknown interrupt, "
+					       "BASR 0x%x, MR 0x%x, SR 0x%x\n",
+					       HOSTNO, basr, NCR5380_read(MODE_REG),
+					       NCR5380_read(STATUS_REG));
+				(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
+#ifdef SUN3_SCSI_VME
+				dregs->csr |= CSR_DMA_ENABLE;
+#endif
+			}
+		} /* if !(SELECTION || PARITY) */
+		handled = 1;
+	} /* BASR & IRQ */ else {
+		printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
+		       "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
+		       NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG));
+		(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
+#ifdef SUN3_SCSI_VME
+		dregs->csr |= CSR_DMA_ENABLE;
+#endif
+	}
+
+	if (!done) {
+		dprintk(NDEBUG_INTR, "scsi%d: in int routine, calling main\n", HOSTNO);
+		/* Put a call to NCR5380_main() on the queue... */
+		queue_main(shost_priv(instance));
+	}
+	return IRQ_RETVAL(handled);
+}
+
+/*
+ * Function : int NCR5380_select(struct Scsi_Host *instance,
+ *                               struct scsi_cmnd *cmd)
+ *
+ * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
+ *	including ARBITRATION, SELECTION, and initial message out for
+ *	IDENTIFY and queue messages.
+ *
+ * Inputs : instance - instantiation of the 5380 driver on which this
+ *	target lives, cmd - SCSI command to execute.
+ *
+ * Returns : -1 if selection could not execute for some reason,
+ *	0 if selection succeeded or failed because the target
+ *	did not respond.
+ *
+ * Side effects :
+ *	If bus busy, arbitration failed, etc, NCR5380_select() will exit
+ *		with registers as they should have been on entry - ie
+ *		SELECT_ENABLE will be set appropriately, the NCR5380
+ *		will cease to drive any SCSI bus signals.
+ *
+ *	If successful : I_T_L or I_T_L_Q nexus will be established,
+ *		instance->connected will be set to cmd.
+ *		SELECT interrupt will be disabled.
+ *
+ *	If failed (no target) : cmd->scsi_done() will be called, and the
+ *		cmd->result host byte set to DID_BAD_TARGET.
+ */
+
+static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
+{
+	SETUP_HOSTDATA(instance);
+	unsigned char tmp[3], phase;
+	unsigned char *data;
+	int len;
+	unsigned long timeout;
+	unsigned long flags;
+
+	hostdata->restart_select = 0;
+	NCR5380_dprint(NDEBUG_ARBITRATION, instance);
+	dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", HOSTNO,
+		   instance->this_id);
+
+	/*
+	 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
+	 * data bus during SELECTION.
+	 */
+
+	local_irq_save(flags);
+	if (hostdata->connected) {
+		local_irq_restore(flags);
+		return -1;
+	}
+	NCR5380_write(TARGET_COMMAND_REG, 0);
+
+	/*
+	 * Start arbitration.
+	 */
+
+	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
+	NCR5380_write(MODE_REG, MR_ARBITRATE);
+
+	local_irq_restore(flags);
+
+	/* Wait for arbitration logic to complete */
+#if defined(NCR_TIMEOUT)
+	{
+		unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
+
+		while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
+		       time_before(jiffies, timeout) && !hostdata->connected)
+			;
+		if (time_after_eq(jiffies, timeout)) {
+			printk("scsi : arbitration timeout at %d\n", __LINE__);
+			NCR5380_write(MODE_REG, MR_BASE);
+			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+			return -1;
+		}
+	}
+#else /* NCR_TIMEOUT */
+	while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
+	       !hostdata->connected)
+		;
+#endif
+
+	dprintk(NDEBUG_ARBITRATION, "scsi%d: arbitration complete\n", HOSTNO);
+
+	if (hostdata->connected) {
+		NCR5380_write(MODE_REG, MR_BASE);
+		return -1;
+	}
+	/*
+	 * The arbitration delay is 2.2us, but this is a minimum and there is
+	 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
+	 * the integral nature of udelay().
+	 *
+	 */
+
+	udelay(3);
+
+	/* Check for lost arbitration */
+	if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
+	    (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
+	    (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
+	    hostdata->connected) {
+		NCR5380_write(MODE_REG, MR_BASE);
+		dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
+			   HOSTNO);
+		return -1;
+	}
+
+	/* after/during arbitration, BSY should be asserted.
+	   IBM DPES-31080 Version S31Q works now */
+	/* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
+	NCR5380_write(INITIATOR_COMMAND_REG,
+		      ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY);
+
+	if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
+	    hostdata->connected) {
+		NCR5380_write(MODE_REG, MR_BASE);
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+		dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
+			   HOSTNO);
+		return -1;
+	}
+
+	/*
+	 * Again, bus clear + bus settle time is 1.2us, however, this is
+	 * a minimum so we'll udelay ceil(1.2)
+	 */
+
+#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
+	/* ++roman: But some targets (see above :-) seem to need a bit more... */
+	udelay(15);
+#else
+	udelay(2);
+#endif
+
+	if (hostdata->connected) {
+		NCR5380_write(MODE_REG, MR_BASE);
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+		return -1;
+	}
+
+	dprintk(NDEBUG_ARBITRATION, "scsi%d: won arbitration\n", HOSTNO);
+
+	/*
+	 * Now that we have won arbitration, start Selection process, asserting
+	 * the host and target ID's on the SCSI bus.
+	 */
+
+	NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id)));
+
+	/*
+	 * Raise ATN while SEL is true before BSY goes false from arbitration,
+	 * since this is the only way to guarantee that we'll get a MESSAGE OUT
+	 * phase immediately after selection.
+	 */
+
+	NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY |
+		      ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL ));
+	NCR5380_write(MODE_REG, MR_BASE);
+
+	/*
+	 * Reselect interrupts must be turned off prior to the dropping of BSY,
+	 * otherwise we will trigger an interrupt.
+	 */
+
+	if (hostdata->connected) {
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+		return -1;
+	}
+
+	NCR5380_write(SELECT_ENABLE_REG, 0);
+
+	/*
+	 * The initiator shall then wait at least two deskew delays and release
+	 * the BSY signal.
+	 */
+	udelay(1);        /* wingel -- wait two bus deskew delay >2*45ns */
+
+	/* Reset BSY */
+	NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA |
+		      ICR_ASSERT_ATN | ICR_ASSERT_SEL));
+
+	/*
+	 * Something weird happens when we cease to drive BSY - looks
+	 * like the board/chip is letting us do another read before the
+	 * appropriate propagation delay has expired, and we're confusing
+	 * a BSY signal from ourselves as the target's response to SELECTION.
+	 *
+	 * A small delay (the 'C++' frontend breaks the pipeline with an
+	 * unnecessary jump, making it work on my 386-33/Trantor T128, the
+	 * tighter 'C' code breaks and requires this) solves the problem -
+	 * the 1 us delay is arbitrary, and only used because this delay will
+	 * be the same on other platforms and since it works here, it should
+	 * work there.
+	 *
+	 * wingel suggests that this could be due to failing to wait
+	 * one deskew delay.
+	 */
+
+	udelay(1);
+
+	dprintk(NDEBUG_SELECTION, "scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
+
+	/*
+	 * The SCSI specification calls for a 250 ms timeout for the actual
+	 * selection.
+	 */
+
+	timeout = jiffies + msecs_to_jiffies(250);
+
+	/*
+	 * XXX very interesting - we're seeing a bounce where the BSY we
+	 * asserted is being reflected / still asserted (propagation delay?)
+	 * and it's detecting as true.  Sigh.
+	 */
+
+#if 0
+	/* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
+	 * IO while SEL is true. But again, there are some disks out the in the
+	 * world that do that nevertheless. (Somebody claimed that this announces
+	 * reselection capability of the target.) So we better skip that test and
+	 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-)
+	 */
+
+	while (time_before(jiffies, timeout) &&
+	       !(NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO)))
+		;
+
+	if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+		NCR5380_reselect(instance);
+		printk(KERN_ERR "scsi%d: reselection after won arbitration?\n",
+		       HOSTNO);
+		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+		return -1;
+	}
+#else
+	while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY))
+		;
+#endif
+
+	/*
+	 * No less than two deskew delays after the initiator detects the
+	 * BSY signal is true, it shall release the SEL signal and may
+	 * change the DATA BUS.                                     -wingel
+	 */
+
+	udelay(1);
+
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
+
+	if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+		if (hostdata->targets_present & (1 << cmd->device->id)) {
+			printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO);
+			if (hostdata->restart_select)
+				printk(KERN_NOTICE "\trestart select\n");
+			NCR5380_dprint(NDEBUG_ANY, instance);
+			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+			return -1;
+		}
+		cmd->result = DID_BAD_TARGET << 16;
+#ifdef SUPPORT_TAGS
+		cmd_free_tag(cmd);
+#endif
+		cmd->scsi_done(cmd);
+		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+		dprintk(NDEBUG_SELECTION, "scsi%d: target did not respond within 250ms\n", HOSTNO);
+		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+		return 0;
+	}
+
+	hostdata->targets_present |= (1 << cmd->device->id);
+
+	/*
+	 * Since we followed the SCSI spec, and raised ATN while SEL
+	 * was true but before BSY was false during selection, the information
+	 * transfer phase should be a MESSAGE OUT phase so that we can send the
+	 * IDENTIFY message.
+	 *
+	 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
+	 * message (2 bytes) with a tag ID that we increment with every command
+	 * until it wraps back to 0.
+	 *
+	 * XXX - it turns out that there are some broken SCSI-II devices,
+	 *	     which claim to support tagged queuing but fail when more than
+	 *	     some number of commands are issued at once.
+	 */
+
+	/* Wait for start of REQ/ACK handshake */
+	while (!(NCR5380_read(STATUS_REG) & SR_REQ))
+		;
+
+	dprintk(NDEBUG_SELECTION, "scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
+		   HOSTNO, cmd->device->id);
+	tmp[0] = IDENTIFY(1, cmd->device->lun);
+
+#ifdef SUPPORT_TAGS
+	if (cmd->tag != TAG_NONE) {
+		tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
+		tmp[2] = cmd->tag;
+		len = 3;
+	} else
+		len = 1;
+#else
+	len = 1;
+	cmd->tag = 0;
+#endif /* SUPPORT_TAGS */
+
+	/* Send message(s) */
+	data = tmp;
+	phase = PHASE_MSGOUT;
+	NCR5380_transfer_pio(instance, &phase, &len, &data);
+	dprintk(NDEBUG_SELECTION, "scsi%d: nexus established.\n", HOSTNO);
+	/* XXX need to handle errors here */
+	hostdata->connected = cmd;
+#ifndef SUPPORT_TAGS
+	hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
+#endif
+#ifdef SUN3_SCSI_VME
+	dregs->csr |= CSR_INTR;
+#endif
+
+	initialize_SCp(cmd);
+
+	return 0;
+}
+
+/*
+ * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
+ *      unsigned char *phase, int *count, unsigned char **data)
+ *
+ * Purpose : transfers data in given phase using polled I/O
+ *
+ * Inputs : instance - instance of driver, *phase - pointer to
+ *	what phase is expected, *count - pointer to number of
+ *	bytes to transfer, **data - pointer to data pointer.
+ *
+ * Returns : -1 when different phase is entered without transferring
+ *	maximum number of bytes, 0 if all bytes are transferred or exit
+ *	is in same phase.
+ *
+ *	Also, *phase, *count, *data are modified in place.
+ *
+ * XXX Note : handling for bus free may be useful.
+ */
+
+/*
+ * Note : this code is not as quick as it could be, however it
+ * IS 100% reliable, and for the actual data transfer where speed
+ * counts, we will always do a pseudo DMA or DMA transfer.
+ */
+
+static int NCR5380_transfer_pio(struct Scsi_Host *instance,
+				unsigned char *phase, int *count,
+				unsigned char **data)
+{
+	register unsigned char p = *phase, tmp;
+	register int c = *count;
+	register unsigned char *d = *data;
+
+	/*
+	 * The NCR5380 chip will only drive the SCSI bus when the
+	 * phase specified in the appropriate bits of the TARGET COMMAND
+	 * REGISTER match the STATUS REGISTER
+	 */
+
+	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
+
+	do {
+		/*
+		 * Wait for assertion of REQ, after which the phase bits will be
+		 * valid
+		 */
+		while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
+			;
+
+		dprintk(NDEBUG_HANDSHAKE, "scsi%d: REQ detected\n", HOSTNO);
+
+		/* Check for phase mismatch */
+		if ((tmp & PHASE_MASK) != p) {
+			dprintk(NDEBUG_PIO, "scsi%d: phase mismatch\n", HOSTNO);
+			NCR5380_dprint_phase(NDEBUG_PIO, instance);
+			break;
+		}
+
+		/* Do actual transfer from SCSI bus to / from memory */
+		if (!(p & SR_IO))
+			NCR5380_write(OUTPUT_DATA_REG, *d);
+		else
+			*d = NCR5380_read(CURRENT_SCSI_DATA_REG);
+
+		++d;
+
+		/*
+		 * The SCSI standard suggests that in MSGOUT phase, the initiator
+		 * should drop ATN on the last byte of the message phase
+		 * after REQ has been asserted for the handshake but before
+		 * the initiator raises ACK.
+		 */
+
+		if (!(p & SR_IO)) {
+			if (!((p & SR_MSG) && c > 1)) {
+				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
+				NCR5380_dprint(NDEBUG_PIO, instance);
+				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
+					      ICR_ASSERT_DATA | ICR_ASSERT_ACK);
+			} else {
+				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
+					      ICR_ASSERT_DATA | ICR_ASSERT_ATN);
+				NCR5380_dprint(NDEBUG_PIO, instance);
+				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
+					      ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
+			}
+		} else {
+			NCR5380_dprint(NDEBUG_PIO, instance);
+			NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
+		}
+
+		while (NCR5380_read(STATUS_REG) & SR_REQ)
+			;
+
+		dprintk(NDEBUG_HANDSHAKE, "scsi%d: req false, handshake complete\n", HOSTNO);
+
+		/*
+		 * We have several special cases to consider during REQ/ACK handshaking :
+		 * 1.  We were in MSGOUT phase, and we are on the last byte of the
+		 *	message.  ATN must be dropped as ACK is dropped.
+		 *
+		 * 2.  We are in a MSGIN phase, and we are on the last byte of the
+		 *	message.  We must exit with ACK asserted, so that the calling
+		 *	code may raise ATN before dropping ACK to reject the message.
+		 *
+		 * 3.  ACK and ATN are clear and the target may proceed as normal.
+		 */
+		if (!(p == PHASE_MSGIN && c == 1)) {
+			if (p == PHASE_MSGOUT && c > 1)
+				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
+			else
+				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+		}
+	} while (--c);
+
+	dprintk(NDEBUG_PIO, "scsi%d: residual %d\n", HOSTNO, c);
+
+	*count = c;
+	*data = d;
+	tmp = NCR5380_read(STATUS_REG);
+	/* The phase read from the bus is valid if either REQ is (already)
+	 * asserted or if ACK hasn't been released yet. The latter is the case if
+	 * we're in MSGIN and all wanted bytes have been received.
+	 */
+	if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
+		*phase = tmp & PHASE_MASK;
+	else
+		*phase = PHASE_UNKNOWN;
+
+	if (!c || (*phase == p))
+		return 0;
+	else
+		return -1;
+}
+
+/*
+ * Function : do_abort (Scsi_Host *host)
+ *
+ * Purpose : abort the currently established nexus.  Should only be
+ *	called from a routine which can drop into a
+ *
+ * Returns : 0 on success, -1 on failure.
+ */
+
+static int do_abort(struct Scsi_Host *instance)
+{
+	unsigned char tmp, *msgptr, phase;
+	int len;
+
+	/* Request message out phase */
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
+
+	/*
+	 * Wait for the target to indicate a valid phase by asserting
+	 * REQ.  Once this happens, we'll have either a MSGOUT phase
+	 * and can immediately send the ABORT message, or we'll have some
+	 * other phase and will have to source/sink data.
+	 *
+	 * We really don't care what value was on the bus or what value
+	 * the target sees, so we just handshake.
+	 */
+
+	while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
+		;
+
+	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
+
+	if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
+			      ICR_ASSERT_ACK);
+		while (NCR5380_read(STATUS_REG) & SR_REQ)
+			;
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
+	}
+
+	tmp = ABORT;
+	msgptr = &tmp;
+	len = 1;
+	phase = PHASE_MSGOUT;
+	NCR5380_transfer_pio(instance, &phase, &len, &msgptr);
+
+	/*
+	 * If we got here, and the command completed successfully,
+	 * we're about to go into bus free state.
+	 */
+
+	return len ? -1 : 0;
+}
+
+#if defined(REAL_DMA)
+/*
+ * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
+ *      unsigned char *phase, int *count, unsigned char **data)
+ *
+ * Purpose : transfers data in given phase using either real
+ *	or pseudo DMA.
+ *
+ * Inputs : instance - instance of driver, *phase - pointer to
+ *	what phase is expected, *count - pointer to number of
+ *	bytes to transfer, **data - pointer to data pointer.
+ *
+ * Returns : -1 when different phase is entered without transferring
+ *	maximum number of bytes, 0 if all bytes or transferred or exit
+ *	is in same phase.
+ *
+ *	Also, *phase, *count, *data are modified in place.
+ *
+ */
+
+
+static int NCR5380_transfer_dma(struct Scsi_Host *instance,
+				unsigned char *phase, int *count,
+				unsigned char **data)
+{
+	SETUP_HOSTDATA(instance);
+	register int c = *count;
+	register unsigned char p = *phase;
+	unsigned long flags;
+
+#if defined(CONFIG_SUN3)
+	/* sanity check */
+	if (!sun3_dma_setup_done) {
+		pr_err("scsi%d: transfer_dma without setup!\n",
+		       instance->host_no);
+		BUG();
+	}
+	hostdata->dma_len = c;
+
+	dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
+		instance->host_no, (p & SR_IO) ? "reading" : "writing",
+		c, (p & SR_IO) ? "to" : "from", *data);
+
+	/* netbsd turns off ints here, why not be safe and do it too */
+	local_irq_save(flags);
+
+	/* send start chain */
+	sun3scsi_dma_start(c, *data);
+
+	if (p & SR_IO) {
+		NCR5380_write(TARGET_COMMAND_REG, 1);
+		NCR5380_read(RESET_PARITY_INTERRUPT_REG);
+		NCR5380_write(INITIATOR_COMMAND_REG, 0);
+		NCR5380_write(MODE_REG,
+			      (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR));
+		NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
+	} else {
+		NCR5380_write(TARGET_COMMAND_REG, 0);
+		NCR5380_read(RESET_PARITY_INTERRUPT_REG);
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_DATA);
+		NCR5380_write(MODE_REG,
+			      (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR));
+		NCR5380_write(START_DMA_SEND_REG, 0);
+	}
+
+#ifdef SUN3_SCSI_VME
+	dregs->csr |= CSR_DMA_ENABLE;
+#endif
+
+	local_irq_restore(flags);
+
+	sun3_dma_active = 1;
+
+#else /* !defined(CONFIG_SUN3) */
+	register unsigned char *d = *data;
+	unsigned char tmp;
+
+	if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
+		*phase = tmp;
+		return -1;
+	}
+
+	if (hostdata->read_overruns && (p & SR_IO))
+		c -= hostdata->read_overruns;
+
+	dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
+		   HOSTNO, (p & SR_IO) ? "reading" : "writing",
+		   c, (p & SR_IO) ? "to" : "from", d);
+
+	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
+
+#ifdef REAL_DMA
+	NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
+#endif /* def REAL_DMA  */
+
+	if (!(hostdata->flags & FLAG_LATE_DMA_SETUP)) {
+		/* On the Medusa, it is a must to initialize the DMA before
+		 * starting the NCR. This is also the cleaner way for the TT.
+		 */
+		local_irq_save(flags);
+		hostdata->dma_len = (p & SR_IO) ?
+			NCR5380_dma_read_setup(instance, d, c) :
+			NCR5380_dma_write_setup(instance, d, c);
+		local_irq_restore(flags);
+	}
+
+	if (p & SR_IO)
+		NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
+	else {
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
+		NCR5380_write(START_DMA_SEND_REG, 0);
+	}
+
+	if (hostdata->flags & FLAG_LATE_DMA_SETUP) {
+		/* On the Falcon, the DMA setup must be done after the last */
+		/* NCR access, else the DMA setup gets trashed!
+		 */
+		local_irq_save(flags);
+		hostdata->dma_len = (p & SR_IO) ?
+			NCR5380_dma_read_setup(instance, d, c) :
+			NCR5380_dma_write_setup(instance, d, c);
+		local_irq_restore(flags);
+	}
+#endif /* !defined(CONFIG_SUN3) */
+
+	return 0;
+}
+#endif /* defined(REAL_DMA) */
+
+/*
+ * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
+ *
+ * Purpose : run through the various SCSI phases and do as the target
+ *	directs us to.  Operates on the currently connected command,
+ *	instance->connected.
+ *
+ * Inputs : instance, instance for which we are doing commands
+ *
+ * Side effects : SCSI things happen, the disconnected queue will be
+ *	modified if a command disconnects, *instance->connected will
+ *	change.
+ *
+ * XXX Note : we need to watch for bus free or a reset condition here
+ *	to recover from an unexpected bus free condition.
+ */
+
+static void NCR5380_information_transfer(struct Scsi_Host *instance)
+{
+	SETUP_HOSTDATA(instance);
+	unsigned long flags;
+	unsigned char msgout = NOP;
+	int sink = 0;
+	int len;
+#if defined(REAL_DMA)
+	int transfersize;
+#endif
+	unsigned char *data;
+	unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
+	struct scsi_cmnd *cmd = (struct scsi_cmnd *) hostdata->connected;
+
+#ifdef SUN3_SCSI_VME
+	dregs->csr |= CSR_INTR;
+#endif
+
+	while (1) {
+		tmp = NCR5380_read(STATUS_REG);
+		/* We only have a valid SCSI phase when REQ is asserted */
+		if (tmp & SR_REQ) {
+			phase = (tmp & PHASE_MASK);
+			if (phase != old_phase) {
+				old_phase = phase;
+				NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
+			}
+#if defined(CONFIG_SUN3)
+			if (phase == PHASE_CMDOUT) {
+#if defined(REAL_DMA)
+				void *d;
+				unsigned long count;
+
+				if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
+					count = cmd->SCp.buffer->length;
+					d = sg_virt(cmd->SCp.buffer);
+				} else {
+					count = cmd->SCp.this_residual;
+					d = cmd->SCp.ptr;
+				}
+				/* this command setup for dma yet? */
+				if ((count >= DMA_MIN_SIZE) && (sun3_dma_setup_done != cmd)) {
+					if (cmd->request->cmd_type == REQ_TYPE_FS) {
+						sun3scsi_dma_setup(d, count,
+						                   rq_data_dir(cmd->request));
+						sun3_dma_setup_done = cmd;
+					}
+				}
+#endif
+#ifdef SUN3_SCSI_VME
+				dregs->csr |= CSR_INTR;
+#endif
+			}
+#endif /* CONFIG_SUN3 */
+
+			if (sink && (phase != PHASE_MSGOUT)) {
+				NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
+
+				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
+					      ICR_ASSERT_ACK);
+				while (NCR5380_read(STATUS_REG) & SR_REQ)
+					;
+				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
+					      ICR_ASSERT_ATN);
+				sink = 0;
+				continue;
+			}
+
+			switch (phase) {
+			case PHASE_DATAOUT:
+#if (NDEBUG & NDEBUG_NO_DATAOUT)
+				printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
+				       "aborted\n", HOSTNO);
+				sink = 1;
+				do_abort(instance);
+				cmd->result = DID_ERROR << 16;
+				cmd->scsi_done(cmd);
+				return;
+#endif
+			case PHASE_DATAIN:
+				/*
+				 * If there is no room left in the current buffer in the
+				 * scatter-gather list, move onto the next one.
+				 */
+
+				if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
+					++cmd->SCp.buffer;
+					--cmd->SCp.buffers_residual;
+					cmd->SCp.this_residual = cmd->SCp.buffer->length;
+					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
+					/* ++roman: Try to merge some scatter-buffers if
+					 * they are at contiguous physical addresses.
+					 */
+					merge_contiguous_buffers(cmd);
+					dprintk(NDEBUG_INFORMATION, "scsi%d: %d bytes and %d buffers left\n",
+						   HOSTNO, cmd->SCp.this_residual,
+						   cmd->SCp.buffers_residual);
+				}
+
+				/*
+				 * The preferred transfer method is going to be
+				 * PSEUDO-DMA for systems that are strictly PIO,
+				 * since we can let the hardware do the handshaking.
+				 *
+				 * For this to work, we need to know the transfersize
+				 * ahead of time, since the pseudo-DMA code will sit
+				 * in an unconditional loop.
+				 */
+
+				/* ++roman: I suggest, this should be
+				 *   #if def(REAL_DMA)
+				 * instead of leaving REAL_DMA out.
+				 */
+
+#if defined(REAL_DMA)
+				if (
+#if !defined(CONFIG_SUN3)
+				    !cmd->device->borken &&
+#endif
+				    (transfersize = NCR5380_dma_xfer_len(instance, cmd, phase)) >= DMA_MIN_SIZE) {
+					len = transfersize;
+					cmd->SCp.phase = phase;
+					if (NCR5380_transfer_dma(instance, &phase,
+					    &len, (unsigned char **)&cmd->SCp.ptr)) {
+						/*
+						 * If the watchdog timer fires, all future
+						 * accesses to this device will use the
+						 * polled-IO. */
+						scmd_printk(KERN_INFO, cmd,
+							"switching to slow handshake\n");
+						cmd->device->borken = 1;
+						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
+							ICR_ASSERT_ATN);
+						sink = 1;
+						do_abort(instance);
+						cmd->result = DID_ERROR << 16;
+						cmd->scsi_done(cmd);
+						/* XXX - need to source or sink data here, as appropriate */
+					} else {
+#ifdef REAL_DMA
+						/* ++roman: When using real DMA,
+						 * information_transfer() should return after
+						 * starting DMA since it has nothing more to
+						 * do.
+						 */
+						return;
+#else
+						cmd->SCp.this_residual -= transfersize - len;
+#endif
+					}
+				} else
+#endif /* defined(REAL_DMA) */
+					NCR5380_transfer_pio(instance, &phase,
+							     (int *)&cmd->SCp.this_residual,
+							     (unsigned char **)&cmd->SCp.ptr);
+#if defined(CONFIG_SUN3) && defined(REAL_DMA)
+				/* if we had intended to dma that command clear it */
+				if (sun3_dma_setup_done == cmd)
+					sun3_dma_setup_done = NULL;
+#endif
+				break;
+			case PHASE_MSGIN:
+				len = 1;
+				data = &tmp;
+				NCR5380_write(SELECT_ENABLE_REG, 0);	/* disable reselects */
+				NCR5380_transfer_pio(instance, &phase, &len, &data);
+				cmd->SCp.Message = tmp;
+
+				switch (tmp) {
+				/*
+				 * Linking lets us reduce the time required to get the
+				 * next command out to the device, hopefully this will
+				 * mean we don't waste another revolution due to the delays
+				 * required by ARBITRATION and another SELECTION.
+				 *
+				 * In the current implementation proposal, low level drivers
+				 * merely have to start the next command, pointed to by
+				 * next_link, done() is called as with unlinked commands.
+				 */
+#ifdef LINKED
+				case LINKED_CMD_COMPLETE:
+				case LINKED_FLG_CMD_COMPLETE:
+					/* Accept message by clearing ACK */
+					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+
+					dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked command "
+						   "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun);
+
+					/* Enable reselect interrupts */
+					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+					/*
+					 * Sanity check : A linked command should only terminate
+					 * with one of these messages if there are more linked
+					 * commands available.
+					 */
+
+					if (!cmd->next_link) {
+						 printk(KERN_NOTICE "scsi%d: target %d lun %llu "
+							"linked command complete, no next_link\n",
+							HOSTNO, cmd->device->id, cmd->device->lun);
+						sink = 1;
+						do_abort(instance);
+						return;
+					}
+
+					initialize_SCp(cmd->next_link);
+					/* The next command is still part of this process; copy it
+					 * and don't free it! */
+					cmd->next_link->tag = cmd->tag;
+					cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
+					dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked request "
+						   "done, calling scsi_done().\n",
+						   HOSTNO, cmd->device->id, cmd->device->lun);
+					cmd->scsi_done(cmd);
+					cmd = hostdata->connected;
+					break;
+#endif /* def LINKED */
+				case ABORT:
+				case COMMAND_COMPLETE:
+					/* Accept message by clearing ACK */
+					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+					dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d, lun %llu "
+						  "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
+
+					local_irq_save(flags);
+					hostdata->retain_dma_intr++;
+					hostdata->connected = NULL;
+#ifdef SUPPORT_TAGS
+					cmd_free_tag(cmd);
+					if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
+						/* Turn a QUEUE FULL status into BUSY, I think the
+						 * mid level cannot handle QUEUE FULL :-( (The
+						 * command is retried after BUSY). Also update our
+						 * queue size to the number of currently issued
+						 * commands now.
+						 */
+						/* ++Andreas: the mid level code knows about
+						   QUEUE_FULL now. */
+						struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][cmd->device->lun];
+						dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu returned "
+							   "QUEUE_FULL after %d commands\n",
+							   HOSTNO, cmd->device->id, cmd->device->lun,
+							   ta->nr_allocated);
+						if (ta->queue_size > ta->nr_allocated)
+							ta->nr_allocated = ta->queue_size;
+					}
+#else
+					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
+#endif
+					/* Enable reselect interrupts */
+					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+
+					/*
+					 * I'm not sure what the correct thing to do here is :
+					 *
+					 * If the command that just executed is NOT a request
+					 * sense, the obvious thing to do is to set the result
+					 * code to the values of the stored parameters.
+					 *
+					 * If it was a REQUEST SENSE command, we need some way to
+					 * differentiate between the failure code of the original
+					 * and the failure code of the REQUEST sense - the obvious
+					 * case is success, where we fall through and leave the
+					 * result code unchanged.
+					 *
+					 * The non-obvious place is where the REQUEST SENSE failed
+					 */
+
+					if (cmd->cmnd[0] != REQUEST_SENSE)
+						cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
+					else if (status_byte(cmd->SCp.Status) != GOOD)
+						cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
+
+					if ((cmd->cmnd[0] == REQUEST_SENSE) &&
+						hostdata->ses.cmd_len) {
+						scsi_eh_restore_cmnd(cmd, &hostdata->ses);
+						hostdata->ses.cmd_len = 0 ;
+					}
+
+					if ((cmd->cmnd[0] != REQUEST_SENSE) &&
+					    (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
+						scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
+
+						dprintk(NDEBUG_AUTOSENSE, "scsi%d: performing request sense\n", HOSTNO);
+
+						LIST(cmd,hostdata->issue_queue);
+						SET_NEXT(cmd, hostdata->issue_queue);
+						hostdata->issue_queue = (struct scsi_cmnd *) cmd;
+						dprintk(NDEBUG_QUEUES, "scsi%d: REQUEST SENSE added to head of "
+							  "issue queue\n", H_NO(cmd));
+					} else {
+						cmd->scsi_done(cmd);
+					}
+
+					local_irq_restore(flags);
+
+					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+					/*
+					 * Restore phase bits to 0 so an interrupted selection,
+					 * arbitration can resume.
+					 */
+					NCR5380_write(TARGET_COMMAND_REG, 0);
+
+					while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
+						barrier();
+
+					local_irq_save(flags);
+					hostdata->retain_dma_intr--;
+					/* ++roman: For Falcon SCSI, release the lock on the
+					 * ST-DMA here if no other commands are waiting on the
+					 * disconnected queue.
+					 */
+					maybe_release_dma_irq(instance);
+					local_irq_restore(flags);
+					return;
+				case MESSAGE_REJECT:
+					/* Accept message by clearing ACK */
+					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+					/* Enable reselect interrupts */
+					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+					switch (hostdata->last_message) {
+					case HEAD_OF_QUEUE_TAG:
+					case ORDERED_QUEUE_TAG:
+					case SIMPLE_QUEUE_TAG:
+						/* The target obviously doesn't support tagged
+						 * queuing, even though it announced this ability in
+						 * its INQUIRY data ?!? (maybe only this LUN?) Ok,
+						 * clear 'tagged_supported' and lock the LUN, since
+						 * the command is treated as untagged further on.
+						 */
+						cmd->device->tagged_supported = 0;
+						hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
+						cmd->tag = TAG_NONE;
+						dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu rejected "
+							   "QUEUE_TAG message; tagged queuing "
+							   "disabled\n",
+							   HOSTNO, cmd->device->id, cmd->device->lun);
+						break;
+					}
+					break;
+				case DISCONNECT:
+					/* Accept message by clearing ACK */
+					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+					local_irq_save(flags);
+					cmd->device->disconnect = 1;
+					LIST(cmd,hostdata->disconnected_queue);
+					SET_NEXT(cmd, hostdata->disconnected_queue);
+					hostdata->connected = NULL;
+					hostdata->disconnected_queue = cmd;
+					local_irq_restore(flags);
+					dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d lun %llu was "
+						  "moved from connected to the "
+						  "disconnected_queue\n", HOSTNO,
+						  cmd->device->id, cmd->device->lun);
+					/*
+					 * Restore phase bits to 0 so an interrupted selection,
+					 * arbitration can resume.
+					 */
+					NCR5380_write(TARGET_COMMAND_REG, 0);
+
+					/* Enable reselect interrupts */
+					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+					/* Wait for bus free to avoid nasty timeouts */
+					while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
+						barrier();
+#ifdef SUN3_SCSI_VME
+					dregs->csr |= CSR_DMA_ENABLE;
+#endif
+					return;
+					/*
+					 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
+					 * operation, in violation of the SCSI spec so we can safely
+					 * ignore SAVE/RESTORE pointers calls.
+					 *
+					 * Unfortunately, some disks violate the SCSI spec and
+					 * don't issue the required SAVE_POINTERS message before
+					 * disconnecting, and we have to break spec to remain
+					 * compatible.
+					 */
+				case SAVE_POINTERS:
+				case RESTORE_POINTERS:
+					/* Accept message by clearing ACK */
+					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+					/* Enable reselect interrupts */
+					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+					break;
+				case EXTENDED_MESSAGE:
+					/*
+					 * Extended messages are sent in the following format :
+					 * Byte
+					 * 0		EXTENDED_MESSAGE == 1
+					 * 1		length (includes one byte for code, doesn't
+					 *		include first two bytes)
+					 * 2		code
+					 * 3..length+1	arguments
+					 *
+					 * Start the extended message buffer with the EXTENDED_MESSAGE
+					 * byte, since spi_print_msg() wants the whole thing.
+					 */
+					extended_msg[0] = EXTENDED_MESSAGE;
+					/* Accept first byte by clearing ACK */
+					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+
+					dprintk(NDEBUG_EXTENDED, "scsi%d: receiving extended message\n", HOSTNO);
+
+					len = 2;
+					data = extended_msg + 1;
+					phase = PHASE_MSGIN;
+					NCR5380_transfer_pio(instance, &phase, &len, &data);
+					dprintk(NDEBUG_EXTENDED, "scsi%d: length=%d, code=0x%02x\n", HOSTNO,
+						   (int)extended_msg[1], (int)extended_msg[2]);
+
+					if (!len && extended_msg[1] <=
+					    (sizeof(extended_msg) - 1)) {
+						/* Accept third byte by clearing ACK */
+						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+						len = extended_msg[1] - 1;
+						data = extended_msg + 3;
+						phase = PHASE_MSGIN;
+
+						NCR5380_transfer_pio(instance, &phase, &len, &data);
+						dprintk(NDEBUG_EXTENDED, "scsi%d: message received, residual %d\n",
+							   HOSTNO, len);
+
+						switch (extended_msg[2]) {
+						case EXTENDED_SDTR:
+						case EXTENDED_WDTR:
+						case EXTENDED_MODIFY_DATA_POINTER:
+						case EXTENDED_EXTENDED_IDENTIFY:
+							tmp = 0;
+						}
+					} else if (len) {
+						printk(KERN_NOTICE "scsi%d: error receiving "
+						       "extended message\n", HOSTNO);
+						tmp = 0;
+					} else {
+						printk(KERN_NOTICE "scsi%d: extended message "
+							   "code %02x length %d is too long\n",
+							   HOSTNO, extended_msg[2], extended_msg[1]);
+						tmp = 0;
+					}
+					/* Fall through to reject message */
+
+					/*
+					 * If we get something weird that we aren't expecting,
+					 * reject it.
+					 */
+				default:
+					if (!tmp) {
+						printk(KERN_INFO "scsi%d: rejecting message ",
+						       instance->host_no);
+						spi_print_msg(extended_msg);
+						printk("\n");
+					} else if (tmp != EXTENDED_MESSAGE)
+						scmd_printk(KERN_INFO, cmd,
+						            "rejecting unknown message %02x\n",
+						            tmp);
+					else
+						scmd_printk(KERN_INFO, cmd,
+						            "rejecting unknown extended message code %02x, length %d\n",
+						            extended_msg[1], extended_msg[0]);
+
+					msgout = MESSAGE_REJECT;
+					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
+					break;
+				} /* switch (tmp) */
+				break;
+			case PHASE_MSGOUT:
+				len = 1;
+				data = &msgout;
+				hostdata->last_message = msgout;
+				NCR5380_transfer_pio(instance, &phase, &len, &data);
+				if (msgout == ABORT) {
+					local_irq_save(flags);
+#ifdef SUPPORT_TAGS
+					cmd_free_tag(cmd);
+#else
+					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
+#endif
+					hostdata->connected = NULL;
+					cmd->result = DID_ERROR << 16;
+					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
+					maybe_release_dma_irq(instance);
+					local_irq_restore(flags);
+					cmd->scsi_done(cmd);
+					return;
+				}
+				msgout = NOP;
+				break;
+			case PHASE_CMDOUT:
+				len = cmd->cmd_len;
+				data = cmd->cmnd;
+				/*
+				 * XXX for performance reasons, on machines with a
+				 * PSEUDO-DMA architecture we should probably
+				 * use the dma transfer function.
+				 */
+				NCR5380_transfer_pio(instance, &phase, &len, &data);
+				break;
+			case PHASE_STATIN:
+				len = 1;
+				data = &tmp;
+				NCR5380_transfer_pio(instance, &phase, &len, &data);
+				cmd->SCp.Status = tmp;
+				break;
+			default:
+				printk("scsi%d: unknown phase\n", HOSTNO);
+				NCR5380_dprint(NDEBUG_ANY, instance);
+			} /* switch(phase) */
+		} /* if (tmp * SR_REQ) */
+	} /* while (1) */
+}
+
+/*
+ * Function : void NCR5380_reselect (struct Scsi_Host *instance)
+ *
+ * Purpose : does reselection, initializing the instance->connected
+ *	field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
+ *	nexus has been reestablished,
+ *
+ * Inputs : instance - this instance of the NCR5380.
+ *
+ */
+
+
+/* it might eventually prove necessary to do a dma setup on
+   reselection, but it doesn't seem to be needed now -- sam */
+
+static void NCR5380_reselect(struct Scsi_Host *instance)
+{
+	SETUP_HOSTDATA(instance);
+	unsigned char target_mask;
+	unsigned char lun;
+#ifdef SUPPORT_TAGS
+	unsigned char tag;
+#endif
+	unsigned char msg[3];
+	int __maybe_unused len;
+	unsigned char __maybe_unused *data, __maybe_unused phase;
+	struct scsi_cmnd *tmp = NULL, *prev;
+
+	/*
+	 * Disable arbitration, etc. since the host adapter obviously
+	 * lost, and tell an interrupted NCR5380_select() to restart.
+	 */
+
+	NCR5380_write(MODE_REG, MR_BASE);
+	hostdata->restart_select = 1;
+
+	target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
+
+	dprintk(NDEBUG_RESELECTION, "scsi%d: reselect\n", HOSTNO);
+
+	/*
+	 * At this point, we have detected that our SCSI ID is on the bus,
+	 * SEL is true and BSY was false for at least one bus settle delay
+	 * (400 ns).
+	 *
+	 * We must assert BSY ourselves, until the target drops the SEL
+	 * signal.
+	 */
+
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
+
+	while (NCR5380_read(STATUS_REG) & SR_SEL)
+		;
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+
+	/*
+	 * Wait for target to go into MSGIN.
+	 */
+
+	while (!(NCR5380_read(STATUS_REG) & SR_REQ))
+		;
+
+#if defined(CONFIG_SUN3) && defined(REAL_DMA)
+	/* acknowledge toggle to MSGIN */
+	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN));
+
+	/* peek at the byte without really hitting the bus */
+	msg[0] = NCR5380_read(CURRENT_SCSI_DATA_REG);
+#else
+	len = 1;
+	data = msg;
+	phase = PHASE_MSGIN;
+	NCR5380_transfer_pio(instance, &phase, &len, &data);
+#endif
+
+	if (!(msg[0] & 0x80)) {
+		printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
+		spi_print_msg(msg);
+		do_abort(instance);
+		return;
+	}
+	lun = (msg[0] & 0x07);
+
+#if defined(SUPPORT_TAGS) && !defined(CONFIG_SUN3)
+	/* If the phase is still MSGIN, the target wants to send some more
+	 * messages. In case it supports tagged queuing, this is probably a
+	 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
+	 */
+	tag = TAG_NONE;
+	if (phase == PHASE_MSGIN && (hostdata->flags & FLAG_TAGGED_QUEUING)) {
+		/* Accept previous IDENTIFY message by clearing ACK */
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+		len = 2;
+		data = msg + 1;
+		if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
+		    msg[1] == SIMPLE_QUEUE_TAG)
+			tag = msg[2];
+		dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at "
+			   "reselection\n", HOSTNO, target_mask, lun, tag);
+	}
+#endif
+
+	/*
+	 * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we
+	 * just reestablished, and remove it from the disconnected queue.
+	 */
+
+	for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue, prev = NULL;
+	     tmp; prev = tmp, tmp = NEXT(tmp)) {
+		if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
+#ifdef SUPPORT_TAGS
+		    && (tag == tmp->tag)
+#endif
+		    ) {
+			if (prev) {
+				REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
+				SET_NEXT(prev, NEXT(tmp));
+			} else {
+				REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
+				hostdata->disconnected_queue = NEXT(tmp);
+			}
+			SET_NEXT(tmp, NULL);
+			break;
+		}
+	}
+
+	if (!tmp) {
+		printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
+#ifdef SUPPORT_TAGS
+		       "tag %d "
+#endif
+		       "not in disconnected_queue.\n",
+		       HOSTNO, target_mask, lun
+#ifdef SUPPORT_TAGS
+		       , tag
+#endif
+			);
+		/*
+		 * Since we have an established nexus that we can't do anything
+		 * with, we must abort it.
+		 */
+		do_abort(instance);
+		return;
+	}
+
+#if defined(CONFIG_SUN3) && defined(REAL_DMA)
+	/* engage dma setup for the command we just saw */
+	{
+		void *d;
+		unsigned long count;
+
+		if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
+			count = tmp->SCp.buffer->length;
+			d = sg_virt(tmp->SCp.buffer);
+		} else {
+			count = tmp->SCp.this_residual;
+			d = tmp->SCp.ptr;
+		}
+		/* setup this command for dma if not already */
+		if ((count >= DMA_MIN_SIZE) && (sun3_dma_setup_done != tmp)) {
+			sun3scsi_dma_setup(d, count, rq_data_dir(tmp->request));
+			sun3_dma_setup_done = tmp;
+		}
+	}
+
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
+#endif
+
+	/* Accept message by clearing ACK */
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+
+#if defined(SUPPORT_TAGS) && defined(CONFIG_SUN3)
+	/* If the phase is still MSGIN, the target wants to send some more
+	 * messages. In case it supports tagged queuing, this is probably a
+	 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
+	 */
+	tag = TAG_NONE;
+	if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
+		/* Accept previous IDENTIFY message by clearing ACK */
+		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+		len = 2;
+		data = msg + 1;
+		if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
+		    msg[1] == SIMPLE_QUEUE_TAG)
+			tag = msg[2];
+		dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at reselection\n"
+			HOSTNO, target_mask, lun, tag);
+	}
+#endif
+
+	hostdata->connected = tmp;
+	dprintk(NDEBUG_RESELECTION, "scsi%d: nexus established, target = %d, lun = %llu, tag = %d\n",
+		   HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
+}
+
+
+/*
+ * Function : int NCR5380_abort (struct scsi_cmnd *cmd)
+ *
+ * Purpose : abort a command
+ *
+ * Inputs : cmd - the scsi_cmnd to abort, code - code to set the
+ *	host byte of the result field to, if zero DID_ABORTED is
+ *	used.
+ *
+ * Returns : SUCCESS - success, FAILED on failure.
+ *
+ * XXX - there is no way to abort the command that is currently
+ *	 connected, you have to wait for it to complete.  If this is
+ *	 a problem, we could implement longjmp() / setjmp(), setjmp()
+ *	 called where the loop started in NCR5380_main().
+ */
+
+static
+int NCR5380_abort(struct scsi_cmnd *cmd)
+{
+	struct Scsi_Host *instance = cmd->device->host;
+	SETUP_HOSTDATA(instance);
+	struct scsi_cmnd *tmp, **prev;
+	unsigned long flags;
+
+	scmd_printk(KERN_NOTICE, cmd, "aborting command\n");
+
+	NCR5380_print_status(instance);
+
+	local_irq_save(flags);
+
+	dprintk(NDEBUG_ABORT, "scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
+		    NCR5380_read(BUS_AND_STATUS_REG),
+		    NCR5380_read(STATUS_REG));
+
+#if 1
+	/*
+	 * Case 1 : If the command is the currently executing command,
+	 * we'll set the aborted flag and return control so that
+	 * information transfer routine can exit cleanly.
+	 */
+
+	if (hostdata->connected == cmd) {
+
+		dprintk(NDEBUG_ABORT, "scsi%d: aborting connected command\n", HOSTNO);
+		/*
+		 * We should perform BSY checking, and make sure we haven't slipped
+		 * into BUS FREE.
+		 */
+
+		/*	NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
+		/*
+		 * Since we can't change phases until we've completed the current
+		 * handshake, we have to source or sink a byte of data if the current
+		 * phase is not MSGOUT.
+		 */
+
+		/*
+		 * Return control to the executing NCR drive so we can clear the
+		 * aborted flag and get back into our main loop.
+		 */
+
+		if (do_abort(instance) == 0) {
+			hostdata->aborted = 1;
+			hostdata->connected = NULL;
+			cmd->result = DID_ABORT << 16;
+#ifdef SUPPORT_TAGS
+			cmd_free_tag(cmd);
+#else
+			hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
+#endif
+			maybe_release_dma_irq(instance);
+			local_irq_restore(flags);
+			cmd->scsi_done(cmd);
+			return SUCCESS;
+		} else {
+			local_irq_restore(flags);
+			printk("scsi%d: abort of connected command failed!\n", HOSTNO);
+			return FAILED;
+		}
+	}
+#endif
+
+	/*
+	 * Case 2 : If the command hasn't been issued yet, we simply remove it
+	 *	    from the issue queue.
+	 */
+	for (prev = (struct scsi_cmnd **)&(hostdata->issue_queue),
+	     tmp = (struct scsi_cmnd *)hostdata->issue_queue;
+	     tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
+		if (cmd == tmp) {
+			REMOVE(5, *prev, tmp, NEXT(tmp));
+			(*prev) = NEXT(tmp);
+			SET_NEXT(tmp, NULL);
+			tmp->result = DID_ABORT << 16;
+			maybe_release_dma_irq(instance);
+			local_irq_restore(flags);
+			dprintk(NDEBUG_ABORT, "scsi%d: abort removed command from issue queue.\n",
+				    HOSTNO);
+			/* Tagged queuing note: no tag to free here, hasn't been assigned
+			 * yet... */
+			tmp->scsi_done(tmp);
+			return SUCCESS;
+		}
+	}
+
+	/*
+	 * Case 3 : If any commands are connected, we're going to fail the abort
+	 *	    and let the high level SCSI driver retry at a later time or
+	 *	    issue a reset.
+	 *
+	 *	    Timeouts, and therefore aborted commands, will be highly unlikely
+	 *          and handling them cleanly in this situation would make the common
+	 *	    case of noresets less efficient, and would pollute our code.  So,
+	 *	    we fail.
+	 */
+
+	if (hostdata->connected) {
+		local_irq_restore(flags);
+		dprintk(NDEBUG_ABORT, "scsi%d: abort failed, command connected.\n", HOSTNO);
+		return FAILED;
+	}
+
+	/*
+	 * Case 4: If the command is currently disconnected from the bus, and
+	 *	there are no connected commands, we reconnect the I_T_L or
+	 *	I_T_L_Q nexus associated with it, go into message out, and send
+	 *      an abort message.
+	 *
+	 * This case is especially ugly. In order to reestablish the nexus, we
+	 * need to call NCR5380_select().  The easiest way to implement this
+	 * function was to abort if the bus was busy, and let the interrupt
+	 * handler triggered on the SEL for reselect take care of lost arbitrations
+	 * where necessary, meaning interrupts need to be enabled.
+	 *
+	 * When interrupts are enabled, the queues may change - so we
+	 * can't remove it from the disconnected queue before selecting it
+	 * because that could cause a failure in hashing the nexus if that
+	 * device reselected.
+	 *
+	 * Since the queues may change, we can't use the pointers from when we
+	 * first locate it.
+	 *
+	 * So, we must first locate the command, and if NCR5380_select()
+	 * succeeds, then issue the abort, relocate the command and remove
+	 * it from the disconnected queue.
+	 */
+
+	for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue; tmp;
+	     tmp = NEXT(tmp)) {
+		if (cmd == tmp) {
+			local_irq_restore(flags);
+			dprintk(NDEBUG_ABORT, "scsi%d: aborting disconnected command.\n", HOSTNO);
+
+			if (NCR5380_select(instance, cmd))
+				return FAILED;
+
+			dprintk(NDEBUG_ABORT, "scsi%d: nexus reestablished.\n", HOSTNO);
+
+			do_abort(instance);
+
+			local_irq_save(flags);
+			for (prev = (struct scsi_cmnd **)&(hostdata->disconnected_queue),
+			     tmp = (struct scsi_cmnd *)hostdata->disconnected_queue;
+			     tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
+				if (cmd == tmp) {
+					REMOVE(5, *prev, tmp, NEXT(tmp));
+					*prev = NEXT(tmp);
+					SET_NEXT(tmp, NULL);
+					tmp->result = DID_ABORT << 16;
+					/* We must unlock the tag/LUN immediately here, since the
+					 * target goes to BUS FREE and doesn't send us another
+					 * message (COMMAND_COMPLETE or the like)
+					 */
+#ifdef SUPPORT_TAGS
+					cmd_free_tag(tmp);
+#else
+					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
+#endif
+					maybe_release_dma_irq(instance);
+					local_irq_restore(flags);
+					tmp->scsi_done(tmp);
+					return SUCCESS;
+				}
+			}
+		}
+	}
+
+	/* Maybe it is sufficient just to release the ST-DMA lock... (if
+	 * possible at all) At least, we should check if the lock could be
+	 * released after the abort, in case it is kept due to some bug.
+	 */
+	maybe_release_dma_irq(instance);
+	local_irq_restore(flags);
+
+	/*
+	 * Case 5 : If we reached this point, the command was not found in any of
+	 *	    the queues.
+	 *
+	 * We probably reached this point because of an unlikely race condition
+	 * between the command completing successfully and the abortion code,
+	 * so we won't panic, but we will notify the user in case something really
+	 * broke.
+	 */
+
+	printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO);
+
+	return FAILED;
+}
+
+
+/*
+ * Function : int NCR5380_reset (struct scsi_cmnd *cmd)
+ *
+ * Purpose : reset the SCSI bus.
+ *
+ * Returns : SUCCESS or FAILURE
+ *
+ */
+
+static int NCR5380_bus_reset(struct scsi_cmnd *cmd)
+{
+	struct Scsi_Host *instance = cmd->device->host;
+	struct NCR5380_hostdata *hostdata = shost_priv(instance);
+	int i;
+	unsigned long flags;
+
+	NCR5380_print_status(instance);
+
+	/* get in phase */
+	NCR5380_write(TARGET_COMMAND_REG,
+		      PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG)));
+	/* assert RST */
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
+	udelay(40);
+	/* reset NCR registers */
+	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
+	NCR5380_write(MODE_REG, MR_BASE);
+	NCR5380_write(TARGET_COMMAND_REG, 0);
+	NCR5380_write(SELECT_ENABLE_REG, 0);
+	/* ++roman: reset interrupt condition! otherwise no interrupts don't get
+	 * through anymore ... */
+	(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
+
+	/* After the reset, there are no more connected or disconnected commands
+	 * and no busy units; so clear the low-level status here to avoid
+	 * conflicts when the mid-level code tries to wake up the affected
+	 * commands!
+	 */
+
+	if (hostdata->issue_queue)
+		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
+	if (hostdata->connected)
+		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd));
+	if (hostdata->disconnected_queue)
+		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
+
+	local_irq_save(flags);
+	hostdata->issue_queue = NULL;
+	hostdata->connected = NULL;
+	hostdata->disconnected_queue = NULL;
+#ifdef SUPPORT_TAGS
+	free_all_tags(hostdata);
+#endif
+	for (i = 0; i < 8; ++i)
+		hostdata->busy[i] = 0;
+#ifdef REAL_DMA
+	hostdata->dma_len = 0;
+#endif
+
+	maybe_release_dma_irq(instance);
+	local_irq_restore(flags);
+
+	return SUCCESS;
+}