atari_NCR5380.c 92.4 KB
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/*
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 * NCR 5380 generic driver routines.  These should make it *trivial*
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 *	to implement 5380 SCSI drivers under Linux with a non-trantor
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 *	architecture.
 *
 *	Note that these routines also work with NR53c400 family chips.
 *
 * Copyright 1993, Drew Eckhardt
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 *	Visionary Computing
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 *	(Unix and Linux consulting and custom programming)
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 *	drew@colorado.edu
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 *	+1 (303) 666-5836
 *
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 * For more information, please consult
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 *
 * 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.
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 *
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 * - 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.
 *
 */

/*
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 * Further development / testing that should be done :
 * 1.  Test linked command handling code after Eric is ready with
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 *     the high level code.
 */
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/* Adapted for the sun3 by Sam Creasey. */

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#include <scsi/scsi_dbg.h>
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#include <scsi/scsi_transport_spi.h>
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#if (NDEBUG & NDEBUG_LISTS)
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#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)
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#else
#define LIST(x,y)
#define REMOVE(w,x,y,z)
#endif

#ifndef notyet
#undef LINKED
#endif

/*
 * Design
 *
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 * This is a generic 5380 driver.  To use it on a different platform,
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 * one simply writes appropriate system specific macros (ie, data
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 * transfer - some PC's will use the I/O bus, 68K's must use
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 * memory mapped) and drops this file in their 'C' wrapper.
 *
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 * As far as command queueing, two queues are maintained for
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 * each 5380 in the system - commands that haven't been issued yet,
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 * 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
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 * while a command is already executing.
 *
 *
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 * Issues specific to the NCR5380 :
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 *
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 * 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
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 * while doing long seek operations.
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 *
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 * The workaround for this is to keep track of devices that have
 * disconnected.  If the device hasn't disconnected, for commands that
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 * should disconnect, we do something like
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 *
 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
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 *
 * Some tweaking of N and M needs to be done.  An algorithm based
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 * on "time to data" would give the best results as long as short time
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 * to datas (ie, on the same track) were considered, however these
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 * 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,
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 * 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.
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 *
 * 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
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 * queue, and NCR5380_main tries to find more work.  If the target is
 * idle for too long, the system will try to sleep.
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 *
 * 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.
 *
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 * On command termination, the done function will be called as
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 * appropriate.
 *
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 * SCSI pointers are maintained in the SCp field of SCSI command
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 * 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
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 * of chips.  To use it, you write an architecture specific functions
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 * and macros and include this file in your driver.
 *
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 * These macros control options :
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 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
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 *	for commands that return with a CHECK CONDITION status.
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 *
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 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
 *	transceivers.
 *
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 * 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 :
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 *
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 * NCR5380_read(register)  - read from the specified register
 *
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 * NCR5380_write(register, value) - write to the specific register
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 *
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 * NCR5380_implementation_fields  - additional fields needed for this
 *      specific implementation of the NCR5380
 *
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 * Either real DMA *or* pseudo DMA may be implemented
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 * REAL functions :
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 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
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 * Note that the DMA setup functions should return the number of bytes
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 *	that they were able to program the controller for.
 *
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 * Also note that generic i386/PC versions of these macros are
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 *	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),
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 * after setting the appropriate host specific fields and ID.  If the
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 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
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 * possible) function may be used.
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 */

static struct Scsi_Host *first_instance = NULL;
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static struct scsi_host_template *the_template = NULL;
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/* Macros ease life... :-) */
#define	SETUP_HOSTDATA(in)				\
    struct NCR5380_hostdata *hostdata =			\
	(struct NCR5380_hostdata *)(in)->hostdata
#define	HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)

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#define	NEXT(cmd)		((struct scsi_cmnd *)(cmd)->host_scribble)
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#define	SET_NEXT(cmd,next)	((cmd)->host_scribble = (void *)(next))
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#define	NEXTADDR(cmd)		((struct scsi_cmnd **)&(cmd)->host_scribble)
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#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.
 */

typedef struct {
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	DECLARE_BITMAP(allocated, MAX_TAGS);
	int nr_allocated;
	int queue_size;
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} TAG_ALLOC;

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static TAG_ALLOC TagAlloc[8][8];	/* 8 targets and 8 LUNs */
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static void __init init_tags(struct NCR5380_hostdata *hostdata)
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{
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	int target, lun;
	TAG_ALLOC *ta;

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	if (!(hostdata->flags & FLAG_TAGGED_QUEUING))
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		return;

	for (target = 0; target < 8; ++target) {
		for (lun = 0; lun < 8; ++lun) {
			ta = &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;
		}
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	}
}


/* 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.
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 */
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static int is_lun_busy(struct scsi_cmnd *cmd, int should_be_tagged)
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{
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	u8 lun = cmd->device->lun;
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	SETUP_HOSTDATA(cmd->device->host);

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	if (hostdata->busy[cmd->device->id] & (1 << lun))
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		return 1;
	if (!should_be_tagged ||
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	    !(hostdata->flags & FLAG_TAGGED_QUEUING) ||
	    !cmd->device->tagged_supported)
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		return 0;
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	if (TagAlloc[cmd->device->id][lun].nr_allocated >=
	    TagAlloc[cmd->device->id][lun].queue_size) {
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		dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d: no free tags\n",
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			   H_NO(cmd), cmd->device->id, lun);
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		return 1;
	}
	return 0;
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}


/* 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.
 */

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static void cmd_get_tag(struct scsi_cmnd *cmd, int should_be_tagged)
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{
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	u8 lun = cmd->device->lun;
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	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 ||
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	    !(hostdata->flags & FLAG_TAGGED_QUEUING) ||
	    !cmd->device->tagged_supported) {
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		cmd->tag = TAG_NONE;
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		hostdata->busy[cmd->device->id] |= (1 << lun);
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		dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d now allocated by untagged "
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			   "command\n", H_NO(cmd), cmd->device->id, lun);
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	} else {
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		TAG_ALLOC *ta = &TagAlloc[cmd->device->id][lun];
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		cmd->tag = find_first_zero_bit(ta->allocated, MAX_TAGS);
		set_bit(cmd->tag, ta->allocated);
		ta->nr_allocated++;
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		dprintk(NDEBUG_TAGS, "scsi%d: using tag %d for target %d lun %d "
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			   "(now %d tags in use)\n",
			   H_NO(cmd), cmd->tag, cmd->device->id,
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			   lun, ta->nr_allocated);
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	}
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}


/* Mark the tag of command 'cmd' as free, or in case of an untagged command,
 * unlock the LUN.
 */

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static void cmd_free_tag(struct scsi_cmnd *cmd)
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{
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	u8 lun = cmd->device->lun;
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	SETUP_HOSTDATA(cmd->device->host);

	if (cmd->tag == TAG_NONE) {
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		hostdata->busy[cmd->device->id] &= ~(1 << lun);
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		dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d untagged cmd finished\n",
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			   H_NO(cmd), cmd->device->id, lun);
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	} else if (cmd->tag >= MAX_TAGS) {
		printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n",
		       H_NO(cmd), cmd->tag);
	} else {
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		TAG_ALLOC *ta = &TagAlloc[cmd->device->id][lun];
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		clear_bit(cmd->tag, ta->allocated);
		ta->nr_allocated--;
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		dprintk(NDEBUG_TAGS, "scsi%d: freed tag %d for target %d lun %d\n",
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			   H_NO(cmd), cmd->tag, cmd->device->id, lun);
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	}
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}


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static void free_all_tags(struct NCR5380_hostdata *hostdata)
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{
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	int target, lun;
	TAG_ALLOC *ta;

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	if (!(hostdata->flags & FLAG_TAGGED_QUEUING))
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		return;

	for (target = 0; target < 8; ++target) {
		for (lun = 0; lun < 8; ++lun) {
			ta = &TagAlloc[target][lun];
			bitmap_zero(ta->allocated, MAX_TAGS);
			ta->nr_allocated = 0;
		}
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	}
}

#endif /* SUPPORT_TAGS */


/*
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 * Function: void merge_contiguous_buffers( struct scsi_cmnd *cmd )
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 *
 * Purpose: Try to merge several scatter-gather requests into one DMA
 *    transfer. This is possible if the scatter buffers lie on
 *    physical contiguous addresses.
 *
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 * Parameters: struct scsi_cmnd *cmd
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 *    The command to work on. The first scatter buffer's data are
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 *    assumed to be already transferred into ptr/this_residual.
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 */

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static void merge_contiguous_buffers(struct scsi_cmnd *cmd)
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{
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#if !defined(CONFIG_SUN3)
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	unsigned long endaddr;
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#if (NDEBUG & NDEBUG_MERGING)
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	unsigned long oldlen = cmd->SCp.this_residual;
	int cnt = 1;
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#endif

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	for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
	     cmd->SCp.buffers_residual &&
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	     virt_to_phys(sg_virt(&cmd->SCp.buffer[1])) == endaddr;) {
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		dprintk(NDEBUG_MERGING, "VTOP(%p) == %08lx -> merging\n",
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			   page_address(sg_page(&cmd->SCp.buffer[1])), endaddr);
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#if (NDEBUG & NDEBUG_MERGING)
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		++cnt;
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#endif
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		++cmd->SCp.buffer;
		--cmd->SCp.buffers_residual;
		cmd->SCp.this_residual += cmd->SCp.buffer->length;
		endaddr += cmd->SCp.buffer->length;
	}
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#if (NDEBUG & NDEBUG_MERGING)
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	if (oldlen != cmd->SCp.this_residual)
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		dprintk(NDEBUG_MERGING, "merged %d buffers from %p, new length %08x\n",
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			   cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
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#endif
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#endif /* !defined(CONFIG_SUN3) */
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}

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/**
 * initialize_SCp - init the scsi pointer field
 * @cmd: command block to set up
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 *
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 * Set up the internal fields in the SCSI command.
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 */

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static inline void initialize_SCp(struct scsi_cmnd *cmd)
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{
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	/*
	 * Initialize the Scsi Pointer field so that all of the commands in the
	 * various queues are valid.
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	 */
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	if (scsi_bufflen(cmd)) {
		cmd->SCp.buffer = scsi_sglist(cmd);
		cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
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		cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
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		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;
485 486
		cmd->SCp.ptr = NULL;
		cmd->SCp.this_residual = 0;
487
	}
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}

#include <linux/delay.h>

#if NDEBUG
static struct {
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	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}
};
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/**
 * NCR5380_print - print scsi bus signals
 * @instance: adapter state to dump
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 *
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 * Print the SCSI bus signals for debugging purposes
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 */

523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551
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");
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}

static struct {
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	unsigned char value;
	const char *name;
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} phases[] = {
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	{PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
	{PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
	{PHASE_UNKNOWN, "UNKNOWN"}
};
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/**
 * NCR5380_print_phase - show SCSI phase
 * @instance: adapter to dump
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 *
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 * Print the current SCSI phase for debugging purposes
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 *
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 * Locks: none
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 */

static void NCR5380_print_phase(struct Scsi_Host *instance)
{
574 575 576 577 578 579 580 581 582 583 584 585
	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);
	}
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}

#endif

/*
 * ++roman: New scheme of calling NCR5380_main()
592
 *
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 * 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.
 */

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#include <linux/gfp.h>
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#include <linux/workqueue.h>
#include <linux/interrupt.h>

607
static volatile int main_running;
608
static DECLARE_WORK(NCR5380_tqueue, NCR5380_main);
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static inline void queue_main(void)
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{
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	if (!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(&NCR5380_tqueue);
	}
	/* else: nothing to do: the running NCR5380_main() will pick up
	   any newly queued command. */
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}


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static inline void NCR5380_all_init(void)
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{
626 627
	static int done = 0;
	if (!done) {
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		dprintk(NDEBUG_INIT, "scsi : NCR5380_all_init()\n");
629 630
		done = 1;
	}
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}

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/**
 * NCR58380_info - report driver and host information
 * @instance: relevant scsi host instance
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 *
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 * For use as the host template info() handler.
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 *
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 * Locks: none
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 */

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static const char *NCR5380_info(struct Scsi_Host *instance)
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{
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	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, "
658
	         "flags { %s}, "
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	         "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,
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	         hostdata->flags & FLAG_TAGGED_QUEUING ? "TAGGED_QUEUING " : "",
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#ifdef DIFFERENTIAL
	         "DIFFERENTIAL "
#endif
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#ifdef REAL_DMA
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	         "REAL_DMA "
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#endif
#ifdef PARITY
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	         "PARITY "
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#endif
#ifdef SUPPORT_TAGS
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	         "SUPPORT_TAGS "
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#endif
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	         "");
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}

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/**
 * NCR5380_print_status - dump controller info
 * @instance: controller to dump
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 *
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 * Print commands in the various queues, called from NCR5380_abort
 * to aid debugging.
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 */

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static void lprint_Scsi_Cmnd(struct scsi_cmnd *cmd)
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{
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	int i, s;
	unsigned char *command;
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	printk("scsi%d: destination target %d, lun %llu\n",
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		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");
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}

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static void NCR5380_print_status(struct Scsi_Host *instance)
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{
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	struct NCR5380_hostdata *hostdata;
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	struct scsi_cmnd *ptr;
706
	unsigned long flags;
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	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
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	hostdata = (struct NCR5380_hostdata *)instance->hostdata;

	local_irq_save(flags);
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	printk("NCR5380: coroutine is%s running.\n",
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		main_running ? "" : "n't");
	if (!hostdata->connected)
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		printk("scsi%d: no currently connected command\n", HOSTNO);
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	else
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		lprint_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected);
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	printk("scsi%d: issue_queue\n", HOSTNO);
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	for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr))
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		lprint_Scsi_Cmnd(ptr);
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	printk("scsi%d: disconnected_queue\n", HOSTNO);
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	for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr;
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	     ptr = NEXT(ptr))
		lprint_Scsi_Cmnd(ptr);
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	local_irq_restore(flags);
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	printk("\n");
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}

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static void show_Scsi_Cmnd(struct scsi_cmnd *cmd, struct seq_file *m)
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{
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	int i, s;
	unsigned char *command;
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	seq_printf(m, "scsi%d: destination target %d, lun %llu\n",
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		H_NO(cmd), cmd->device->id, cmd->device->lun);
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	seq_printf(m, "        command = ");
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	command = cmd->cmnd;
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	seq_printf(m, "%2d (0x%02x)", command[0], command[0]);
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	for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
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		seq_printf(m, " %02x", command[i]);
	seq_printf(m, "\n");
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}

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static int __maybe_unused NCR5380_show_info(struct seq_file *m,
                                            struct Scsi_Host *instance)
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{
	struct NCR5380_hostdata *hostdata;
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	struct scsi_cmnd *ptr;
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	unsigned long flags;

	hostdata = (struct NCR5380_hostdata *)instance->hostdata;

	local_irq_save(flags);
	seq_printf(m, "NCR5380: coroutine is%s running.\n",
		main_running ? "" : "n't");
	if (!hostdata->connected)
		seq_printf(m, "scsi%d: no currently connected command\n", HOSTNO);
	else
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		show_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected, m);
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	seq_printf(m, "scsi%d: issue_queue\n", HOSTNO);
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	for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr))
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		show_Scsi_Cmnd(ptr, m);

	seq_printf(m, "scsi%d: disconnected_queue\n", HOSTNO);
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	for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr;
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	     ptr = NEXT(ptr))
		show_Scsi_Cmnd(ptr, m);

	local_irq_restore(flags);
	return 0;
}
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/**
 * NCR5380_init - initialise an NCR5380
 * @instance: adapter to configure
 * @flags: control flags
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 *
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 * Initializes *instance and corresponding 5380 chip,
 * with flags OR'd into the initial flags value.
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 *
 * Notes : I assume that the host, hostno, and id bits have been
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 * set correctly. I don't care about the irq and other fields.
786
 *
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 * Returns 0 for success
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 */

790
static int __init NCR5380_init(struct Scsi_Host *instance, int flags)
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{
792 793 794 795 796 797 798 799 800 801 802 803 804
	int i;
	SETUP_HOSTDATA(instance);

	NCR5380_all_init();

	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;
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#ifdef SUPPORT_TAGS
806
	init_tags(hostdata);
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#endif
#if defined (REAL_DMA)
809
	hostdata->dma_len = 0;
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#endif
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	hostdata->targets_present = 0;
	hostdata->connected = NULL;
	hostdata->issue_queue = NULL;
	hostdata->disconnected_queue = NULL;
815
	hostdata->flags = flags;
816 817 818 819 820

	if (!the_template) {
		the_template = instance->hostt;
		first_instance = instance;
	}
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	prepare_info(instance);

824 825 826 827
	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);
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829
	return 0;
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}

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/**
 * NCR5380_exit - remove an NCR5380
 * @instance: adapter to remove
 *
 * Assumes that no more work can be queued (e.g. by NCR5380_intr).
 */

839 840
static void NCR5380_exit(struct Scsi_Host *instance)
{
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	cancel_work_sync(&NCR5380_tqueue);
842 843
}

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/**
 * NCR5380_queue_command - queue a command
 * @instance: the relevant SCSI adapter
 * @cmd: SCSI command
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 *
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 * 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.
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 */

854 855
static int NCR5380_queue_command(struct Scsi_Host *instance,
                                 struct scsi_cmnd *cmd)
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{
857
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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	struct scsi_cmnd *tmp;
859
	unsigned long flags;
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#if (NDEBUG & NDEBUG_NO_WRITE)
862 863 864 865 866 867
	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);
868
		cmd->scsi_done(cmd);
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		return 0;
	}
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#endif /* (NDEBUG & NDEBUG_NO_WRITE) */

873 874 875 876 877
	/*
	 * We use the host_scribble field as a pointer to the next command
	 * in a queue
	 */

878
	SET_NEXT(cmd, NULL);
879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899
	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.
	 */
900
	if (!NCR5380_acquire_dma_irq(instance))
901 902 903 904
		return SCSI_MLQUEUE_HOST_BUSY;

	local_irq_save(flags);

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	/*
	 * 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.
	 */

912 913
	if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
		LIST(cmd, hostdata->issue_queue);
914
		SET_NEXT(cmd, hostdata->issue_queue);
915 916
		hostdata->issue_queue = cmd;
	} else {
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		for (tmp = (struct scsi_cmnd *)hostdata->issue_queue;
918 919 920
		     NEXT(tmp); tmp = NEXT(tmp))
			;
		LIST(cmd, tmp);
921
		SET_NEXT(tmp, cmd);
922 923 924
	}
	local_irq_restore(flags);

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	dprintk(NDEBUG_QUEUES, "scsi%d: command added to %s of queue\n", H_NO(cmd),
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		  (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.
	 */
935
	if (in_interrupt() || irqs_disabled())
936 937 938 939
		queue_main();
	else
		NCR5380_main(NULL);
	return 0;
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}

942 943 944 945 946 947 948 949 950 951 952 953
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);
}

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/**
 * NCR5380_main - NCR state machines
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 *
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 * 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.
961
 *
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 * Locks: called as its own thread with no locks held.
963 964
 */

965
static void NCR5380_main(struct work_struct *work)
L
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{
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	struct scsi_cmnd *tmp, *prev;
968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003
	struct Scsi_Host *instance = first_instance;
	struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
	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 (main_running)
		return;
	main_running = 1;

	local_save_flags(flags);
	do {
		local_irq_disable();	/* Freeze request queues */
		done = 1;

		if (!hostdata->connected) {
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			dprintk(NDEBUG_MAIN, "scsi%d: not connected\n", HOSTNO);
1005 1006 1007 1008
			/*
			 * Search through the issue_queue for a command destined
			 * for a target that's not busy.
			 */
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#if (NDEBUG & NDEBUG_LISTS)
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			for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, prev = NULL;
1011 1012 1013 1014 1015 1016
			     tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
				;
			/*printk("%p  ", tmp);*/
			if ((tmp == prev) && tmp)
				printk(" LOOP\n");
			/* else printk("\n"); */
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#endif
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			for (tmp = (struct scsi_cmnd *) hostdata->issue_queue,
1019
			     prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) {
H
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				u8 lun = tmp->device->lun;
L
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1021

1022 1023 1024 1025
				dprintk(NDEBUG_LISTS,
				        "MAIN tmp=%p target=%d busy=%d lun=%d\n",
				        tmp, scmd_id(tmp), hostdata->busy[scmd_id(tmp)],
				        lun);
1026 1027 1028
				/*  When we find one, remove it from the issue queue. */
				/* ++guenther: possible race with Falcon locking */
				if (
L
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#ifdef SUPPORT_TAGS
1030
				    !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
L
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#else
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1032
				    !(hostdata->busy[tmp->device->id] & (1 << lun))
L
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#endif
1034 1035 1036 1037 1038
				    ) {
					/* ++guenther: just to be sure, this must be atomic */
					local_irq_disable();
					if (prev) {
						REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1039
						SET_NEXT(prev, NEXT(tmp));
1040 1041 1042 1043
					} else {
						REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
						hostdata->issue_queue = NEXT(tmp);
					}
1044
					SET_NEXT(tmp, NULL);
1045
					hostdata->retain_dma_intr++;
1046 1047 1048 1049 1050 1051 1052 1053 1054 1055

					/* 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.
					 */
F
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					dprintk(NDEBUG_MAIN, "scsi%d: main(): command for target %d "
1057
						    "lun %d removed from issue_queue\n",
H
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1058
						    HOSTNO, tmp->device->id, lun);
1059 1060 1061 1062 1063 1064 1065 1066 1067 1068
					/*
					 * 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.
					 */

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#ifdef SUPPORT_TAGS
1070
					cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE);
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1071
#endif
1072
					if (!NCR5380_select(instance, tmp)) {
1073
						local_irq_disable();
1074
						hostdata->retain_dma_intr--;
1075
						/* release if target did not response! */
1076 1077
						maybe_release_dma_irq(instance);
						local_irq_restore(flags);
1078 1079 1080 1081
						break;
					} else {
						local_irq_disable();
						LIST(tmp, hostdata->issue_queue);
1082
						SET_NEXT(tmp, hostdata->issue_queue);
1083
						hostdata->issue_queue = tmp;
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1084
#ifdef SUPPORT_TAGS
1085
						cmd_free_tag(tmp);
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1086
#endif
1087
						hostdata->retain_dma_intr--;
1088
						local_irq_restore(flags);
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						dprintk(NDEBUG_MAIN, "scsi%d: main(): select() failed, "
1090 1091 1092 1093 1094 1095 1096 1097 1098
							    "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
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#ifdef REAL_DMA
1100
		    && !hostdata->dma_len
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#endif
1102 1103
		    ) {
			local_irq_restore(flags);
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			dprintk(NDEBUG_MAIN, "scsi%d: main: performing information transfer\n",
1105 1106
				    HOSTNO);
			NCR5380_information_transfer(instance);
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			dprintk(NDEBUG_MAIN, "scsi%d: main: done set false\n", HOSTNO);
1108 1109 1110
			done = 0;
		}
	} while (!done);
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1112 1113 1114 1115 1116
	/* 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... */
	main_running = 0;
	local_irq_restore(flags);
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1117 1118 1119 1120 1121 1122 1123 1124
}


#ifdef REAL_DMA
/*
 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
 *
 * Purpose : Called by interrupt handler when DMA finishes or a phase
1125
 *	mismatch occurs (which would finish the DMA transfer).
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 *
 * Inputs : instance - this instance of the NCR5380.
 *
 */

1131
static void NCR5380_dma_complete(struct Scsi_Host *instance)
L
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1132
{
1133
	SETUP_HOSTDATA(instance);
1134 1135
	int transfered;
	unsigned char **data;
1136
	volatile int *count;
1137 1138
	int saved_data = 0, overrun = 0;
	unsigned char p;
1139 1140 1141 1142 1143

	if (!hostdata->connected) {
		printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
		       "no connected cmd\n", HOSTNO);
		return;
L
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1144
	}
1145

1146
	if (hostdata->read_overruns) {
1147 1148 1149 1150 1151 1152 1153 1154
		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;
F
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				dprintk(NDEBUG_DMA, "scsi%d: read overrun handled\n", HOSTNO);
1156 1157 1158 1159
			}
		}
	}

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	dprintk(NDEBUG_DMA, "scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1161 1162 1163
		   HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
		   NCR5380_read(STATUS_REG));

1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181
#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

1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193
	(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
	NCR5380_write(MODE_REG, MR_BASE);
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	transfered = 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 += transfered;
	*count -= transfered;

1194
	if (hostdata->read_overruns) {
1195 1196
		int cnt, toPIO;

1197
		if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
1198
			cnt = toPIO = hostdata->read_overruns;
1199
			if (overrun) {
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				dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n");
1201 1202 1203 1204 1205
				*(*data)++ = saved_data;
				(*count)--;
				cnt--;
				toPIO--;
			}
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			dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
1207 1208 1209
			NCR5380_transfer_pio(instance, &p, &cnt, data);
			*count -= toPIO - cnt;
		}
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	}
}
#endif /* REAL_DMA */


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/**
 * NCR5380_intr - generic NCR5380 irq handler
 * @irq: interrupt number
 * @dev_id: device info
L
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 *
F
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 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
 * from the disconnected queue, and restarting NCR5380_main()
 * as required.
L
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1223 1224
 */

1225
static irqreturn_t NCR5380_intr(int irq, void *dev_id)
L
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1226
{
1227 1228 1229 1230
	struct Scsi_Host *instance = first_instance;
	int done = 1, handled = 0;
	unsigned char basr;

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	dprintk(NDEBUG_INTR, "scsi%d: NCR5380 irq triggered\n", HOSTNO);
1232 1233 1234

	/* Look for pending interrupts */
	basr = NCR5380_read(BUS_AND_STATUS_REG);
F
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	dprintk(NDEBUG_INTR, "scsi%d: BASR=%02x\n", HOSTNO, basr);
1236 1237
	/* dispatch to appropriate routine if found and done=0 */
	if (basr & BASR_IRQ) {
1238
		NCR5380_dprint(NDEBUG_INTR, instance);
1239 1240
		if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
			done = 0;
F
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			dprintk(NDEBUG_INTR, "scsi%d: SEL interrupt\n", HOSTNO);
1242 1243 1244
			NCR5380_reselect(instance);
			(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
		} else if (basr & BASR_PARITY_ERROR) {
F
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			dprintk(NDEBUG_INTR, "scsi%d: PARITY interrupt\n", HOSTNO);
1246 1247
			(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
		} else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
F
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			dprintk(NDEBUG_INTR, "scsi%d: RESET interrupt\n", HOSTNO);
1249 1250 1251 1252 1253 1254
			(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
		} else {
			/*
			 * The rest of the interrupt conditions can occur only during a
			 * DMA transfer
			 */
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1255 1256

#if defined(REAL_DMA)
1257 1258 1259 1260 1261 1262 1263 1264 1265 1266
			/*
			 * 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))) {

F
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1267
				dprintk(NDEBUG_INTR, "scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1268 1269 1270
				NCR5380_dma_complete( instance );
				done = 0;
			} else
L
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1271
#endif /* REAL_DMA */
1272
			{
L
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1273
/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1274
				if (basr & BASR_PHASE_MATCH)
1275
					dprintk(NDEBUG_INTR, "scsi%d: unknown interrupt, "
1276 1277 1278 1279
					       "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);
1280 1281 1282
#ifdef SUN3_SCSI_VME
				dregs->csr |= CSR_DMA_ENABLE;
#endif
1283 1284 1285 1286 1287 1288 1289 1290
			}
		} /* 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);
1291 1292 1293
#ifdef SUN3_SCSI_VME
		dregs->csr |= CSR_DMA_ENABLE;
#endif
1294 1295 1296
	}

	if (!done) {
F
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1297
		dprintk(NDEBUG_INTR, "scsi%d: in int routine, calling main\n", HOSTNO);
1298 1299 1300 1301
		/* Put a call to NCR5380_main() on the queue... */
		queue_main();
	}
	return IRQ_RETVAL(handled);
L
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1302 1303
}

1304
/*
F
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1305 1306
 * Function : int NCR5380_select(struct Scsi_Host *instance,
 *                               struct scsi_cmnd *cmd)
L
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1307 1308
 *
 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1309 1310
 *	including ARBITRATION, SELECTION, and initial message out for
 *	IDENTIFY and queue messages.
L
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1311
 *
1312
 * Inputs : instance - instantiation of the 5380 driver on which this
1313
 *	target lives, cmd - SCSI command to execute.
1314
 *
L
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1315
 * Returns : -1 if selection could not execute for some reason,
1316 1317
 *	0 if selection succeeded or failed because the target
 *	did not respond.
L
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1318
 *
1319 1320
 * Side effects :
 *	If bus busy, arbitration failed, etc, NCR5380_select() will exit
L
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1321 1322 1323 1324
 *		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.
 *
1325 1326 1327
 *	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.
L
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1328
 *
1329
 *	If failed (no target) : cmd->scsi_done() will be called, and the
L
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1330 1331 1332
 *		cmd->result host byte set to DID_BAD_TARGET.
 */

F
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1333
static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
L
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1334
{
1335 1336 1337 1338 1339 1340 1341 1342
	SETUP_HOSTDATA(instance);
	unsigned char tmp[3], phase;
	unsigned char *data;
	int len;
	unsigned long timeout;
	unsigned long flags;

	hostdata->restart_select = 0;
1343
	NCR5380_dprint(NDEBUG_ARBITRATION, instance);
F
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1344
	dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", HOSTNO,
1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357
		   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);
L
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1358

1359 1360 1361
	/*
	 * Start arbitration.
	 */
L
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1362

1363 1364
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
	NCR5380_write(MODE_REG, MR_ARBITRATE);
L
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1365

1366
	local_irq_restore(flags);
L
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1367

1368
	/* Wait for arbitration logic to complete */
M
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1369
#if defined(NCR_TIMEOUT)
1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382
	{
		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;
		}
	}
L
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1383
#else /* NCR_TIMEOUT */
1384 1385 1386
	while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
	       !hostdata->connected)
		;
L
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1387 1388
#endif

F
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1389
	dprintk(NDEBUG_ARBITRATION, "scsi%d: arbitration complete\n", HOSTNO);
1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409

	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);
F
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1410
		dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1411 1412 1413
			   HOSTNO);
		return -1;
	}
L
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1414

1415 1416 1417 1418 1419 1420 1421 1422 1423 1424
	/* 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);
F
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1425
		dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1426 1427 1428 1429 1430 1431 1432 1433
			   HOSTNO);
		return -1;
	}

	/*
	 * Again, bus clear + bus settle time is 1.2us, however, this is
	 * a minimum so we'll udelay ceil(1.2)
	 */
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#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1436 1437
	/* ++roman: But some targets (see above :-) seem to need a bit more... */
	udelay(15);
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#else
1439
	udelay(2);
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#endif
1441 1442 1443 1444 1445 1446 1447

	if (hostdata->connected) {
		NCR5380_write(MODE_REG, MR_BASE);
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		return -1;
	}

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	dprintk(NDEBUG_ARBITRATION, "scsi%d: won arbitration\n", HOSTNO);
1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464

	/*
	 * 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 ));
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	NCR5380_write(MODE_REG, MR_BASE);

1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477
	/*
	 * 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);
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1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504
	/*
	 * 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.
	 */
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1506
	udelay(1);
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	dprintk(NDEBUG_SELECTION, "scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
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1510 1511 1512 1513
	/*
	 * The SCSI specification calls for a 250 ms timeout for the actual
	 * selection.
	 */
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	timeout = jiffies + (250 * HZ / 1000);
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1517 1518 1519 1520 1521
	/*
	 * 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.
	 */
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#if 0
1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542
	/* ++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;
	}
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#else
1544 1545
	while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY))
		;
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#endif

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	/*
	 * 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
	 */
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1554
	udelay(1);
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1556
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
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1558 1559 1560 1561 1562 1563
	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");
1564
			NCR5380_dprint(NDEBUG_ANY, instance);
1565 1566 1567 1568
			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
			return -1;
		}
		cmd->result = DID_BAD_TARGET << 16;
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#ifdef SUPPORT_TAGS
1570
		cmd_free_tag(cmd);
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#endif
1572 1573
		cmd->scsi_done(cmd);
		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
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		dprintk(NDEBUG_SELECTION, "scsi%d: target did not respond within 250ms\n", HOSTNO);
1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599
		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))
		;

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	dprintk(NDEBUG_SELECTION, "scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1601 1602
		   HOSTNO, cmd->device->id);
	tmp[0] = IDENTIFY(1, cmd->device->lun);
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#ifdef SUPPORT_TAGS
1605 1606 1607 1608 1609 1610
	if (cmd->tag != TAG_NONE) {
		tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
		tmp[2] = cmd->tag;
		len = 3;
	} else
		len = 1;
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#else
1612 1613
	len = 1;
	cmd->tag = 0;
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#endif /* SUPPORT_TAGS */

1616 1617 1618 1619
	/* Send message(s) */
	data = tmp;
	phase = PHASE_MSGOUT;
	NCR5380_transfer_pio(instance, &phase, &len, &data);
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	dprintk(NDEBUG_SELECTION, "scsi%d: nexus established.\n", HOSTNO);
1621 1622
	/* XXX need to handle errors here */
	hostdata->connected = cmd;
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#ifndef SUPPORT_TAGS
1624 1625
	hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
#endif
1626 1627 1628
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif
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1630
	initialize_SCp(cmd);
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1632
	return 0;
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}

1635 1636
/*
 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
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 *      unsigned char *phase, int *count, unsigned char **data)
 *
 * Purpose : transfers data in given phase using polled I/O
 *
1641 1642
 * Inputs : instance - instance of driver, *phase - pointer to
 *	what phase is expected, *count - pointer to number of
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 *	bytes to transfer, **data - pointer to data pointer.
1644
 *
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 * Returns : -1 when different phase is entered without transferring
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 *	maximum number of bytes, 0 if all bytes are transferred or exit
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 *	is in same phase.
 *
1649
 *	Also, *phase, *count, *data are modified in place.
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 *
 * XXX Note : handling for bus free may be useful.
 */

/*
1655
 * Note : this code is not as quick as it could be, however it
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 * IS 100% reliable, and for the actual data transfer where speed
 * counts, we will always do a pseudo DMA or DMA transfer.
 */

1660 1661 1662
static int NCR5380_transfer_pio(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
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{
1664 1665 1666 1667 1668 1669 1670 1671
	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
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	 */

1674
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
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1676 1677 1678 1679 1680 1681 1682
	do {
		/*
		 * Wait for assertion of REQ, after which the phase bits will be
		 * valid
		 */
		while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
			;
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		dprintk(NDEBUG_HANDSHAKE, "scsi%d: REQ detected\n", HOSTNO);
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1686 1687
		/* Check for phase mismatch */
		if ((tmp & PHASE_MASK) != p) {
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			dprintk(NDEBUG_PIO, "scsi%d: phase mismatch\n", HOSTNO);
1689
			NCR5380_dprint_phase(NDEBUG_PIO, instance);
1690 1691
			break;
		}
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1693 1694 1695 1696 1697
		/* 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);
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1699
		++d;
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1701 1702 1703 1704 1705 1706
		/*
		 * 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.
		 */
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1708 1709 1710
		if (!(p & SR_IO)) {
			if (!((p & SR_MSG) && c > 1)) {
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1711
				NCR5380_dprint(NDEBUG_PIO, instance);
1712 1713 1714 1715 1716
				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);
1717
				NCR5380_dprint(NDEBUG_PIO, instance);
1718 1719 1720 1721
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
					      ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
			}
		} else {
1722
			NCR5380_dprint(NDEBUG_PIO, instance);
1723 1724
			NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
		}
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1726 1727 1728
		while (NCR5380_read(STATUS_REG) & SR_REQ)
			;

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		dprintk(NDEBUG_HANDSHAKE, "scsi%d: req false, handshake complete\n", HOSTNO);
1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749

		/*
		 * 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);

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	dprintk(NDEBUG_PIO, "scsi%d: residual %d\n", HOSTNO, c);
1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767

	*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;
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}

/*
 * Function : do_abort (Scsi_Host *host)
1772 1773 1774 1775
 *
 * Purpose : abort the currently established nexus.  Should only be
 *	called from a routine which can drop into a
 *
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 * Returns : 0 on success, -1 on failure.
 */

1779
static int do_abort(struct Scsi_Host *host)
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{
1781 1782 1783 1784
	unsigned char tmp, *msgptr, phase;
	int len;

	/* Request message out phase */
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	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796

	/*
	 * 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.
	 */

1797
	while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821
		;

	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(host, &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;
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}

#if defined(REAL_DMA)
1825 1826
/*
 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
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 *      unsigned char *phase, int *count, unsigned char **data)
 *
 * Purpose : transfers data in given phase using either real
 *	or pseudo DMA.
 *
1832 1833
 * Inputs : instance - instance of driver, *phase - pointer to
 *	what phase is expected, *count - pointer to number of
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 *	bytes to transfer, **data - pointer to data pointer.
1835
 *
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 * Returns : -1 when different phase is entered without transferring
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 *	maximum number of bytes, 0 if all bytes or transferred or exit
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 *	is in same phase.
 *
1840
 *	Also, *phase, *count, *data are modified in place.
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 *
 */


1845 1846 1847
static int NCR5380_transfer_dma(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
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{
1849 1850 1851
	SETUP_HOSTDATA(instance);
	register int c = *count;
	register unsigned char p = *phase;
1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897
	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) */
1898 1899 1900 1901 1902 1903 1904
	register unsigned char *d = *data;
	unsigned char tmp;

	if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
		*phase = tmp;
		return -1;
	}
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1906 1907
	if (hostdata->read_overruns && (p & SR_IO))
		c -= hostdata->read_overruns;
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	dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1910 1911
		   HOSTNO, (p & SR_IO) ? "reading" : "writing",
		   c, (p & SR_IO) ? "to" : "from", d);
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1913
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
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#ifdef REAL_DMA
1916
	NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
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#endif /* def REAL_DMA  */

1919
	if (!(hostdata->flags & FLAG_LATE_DMA_SETUP)) {
1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936
		/* 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);
	}

1937
	if (hostdata->flags & FLAG_LATE_DMA_SETUP) {
1938 1939 1940 1941 1942 1943 1944 1945 1946
		/* 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);
	}
1947 1948
#endif /* !defined(CONFIG_SUN3) */

1949
	return 0;
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1950 1951 1952 1953 1954 1955
}
#endif /* defined(REAL_DMA) */

/*
 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
 *
1956 1957
 * Purpose : run through the various SCSI phases and do as the target
 *	directs us to.  Operates on the currently connected command,
L
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1958 1959 1960 1961
 *	instance->connected.
 *
 * Inputs : instance, instance for which we are doing commands
 *
1962
 * Side effects : SCSI things happen, the disconnected queue will be
L
Linus Torvalds 已提交
1963 1964 1965
 *	modified if a command disconnects, *instance->connected will
 *	change.
 *
1966 1967
 * XXX Note : we need to watch for bus free or a reset condition here
 *	to recover from an unexpected bus free condition.
L
Linus Torvalds 已提交
1968
 */
1969 1970

static void NCR5380_information_transfer(struct Scsi_Host *instance)
L
Linus Torvalds 已提交
1971
{
1972 1973 1974 1975 1976
	SETUP_HOSTDATA(instance);
	unsigned long flags;
	unsigned char msgout = NOP;
	int sink = 0;
	int len;
L
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1977
#if defined(REAL_DMA)
1978
	int transfersize;
L
Linus Torvalds 已提交
1979
#endif
1980 1981
	unsigned char *data;
	unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
F
Finn Thain 已提交
1982
	struct scsi_cmnd *cmd = (struct scsi_cmnd *) hostdata->connected;
1983

1984 1985 1986 1987
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif

1988 1989 1990 1991 1992 1993 1994
	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;
1995
				NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
1996
			}
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023
#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 */
L
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2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039
			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:
L
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2040
#if (NDEBUG & NDEBUG_NO_DATAOUT)
2041 2042 2043 2044 2045
				printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
				       "aborted\n", HOSTNO);
				sink = 1;
				do_abort(instance);
				cmd->result = DID_ERROR << 16;
2046
				cmd->scsi_done(cmd);
2047
				return;
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Linus Torvalds 已提交
2048
#endif
2049 2050 2051 2052 2053 2054 2055 2056 2057 2058
			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;
J
Jens Axboe 已提交
2059
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2060 2061 2062 2063
					/* ++roman: Try to merge some scatter-buffers if
					 * they are at contiguous physical addresses.
					 */
					merge_contiguous_buffers(cmd);
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Finn Thain 已提交
2064
					dprintk(NDEBUG_INFORMATION, "scsi%d: %d bytes and %d buffers left\n",
2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082
						   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.
				 */
L
Linus Torvalds 已提交
2083 2084

#if defined(REAL_DMA)
2085 2086 2087 2088 2089
				if (
#if !defined(CONFIG_SUN3)
				    !cmd->device->borken &&
#endif
				    (transfersize = NCR5380_dma_xfer_len(instance, cmd, phase)) >= DMA_MIN_SIZE) {
2090 2091 2092 2093 2094 2095 2096 2097
					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. */
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Finn Thain 已提交
2098 2099
						scmd_printk(KERN_INFO, cmd,
							"switching to slow handshake\n");
2100 2101 2102 2103 2104 2105
						cmd->device->borken = 1;
						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
							ICR_ASSERT_ATN);
						sink = 1;
						do_abort(instance);
						cmd->result = DID_ERROR << 16;
2106
						cmd->scsi_done(cmd);
2107 2108
						/* XXX - need to source or sink data here, as appropriate */
					} else {
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2109
#ifdef REAL_DMA
2110 2111 2112 2113 2114 2115 2116 2117
						/* ++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;
L
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2118
#endif
2119 2120
					}
				} else
L
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2121
#endif /* defined(REAL_DMA) */
2122 2123 2124
					NCR5380_transfer_pio(instance, &phase,
							     (int *)&cmd->SCp.this_residual,
							     (unsigned char **)&cmd->SCp.ptr);
2125 2126 2127 2128 2129
#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
2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148
				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.
				 */
L
Linus Torvalds 已提交
2149
#ifdef LINKED
2150 2151 2152 2153 2154
				case LINKED_CMD_COMPLETE:
				case LINKED_FLG_CMD_COMPLETE:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

H
Hannes Reinecke 已提交
2155
					dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked command "
2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166
						   "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) {
H
Hannes Reinecke 已提交
2167
						 printk(KERN_NOTICE "scsi%d: target %d lun %llu "
2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179
							"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);
H
Hannes Reinecke 已提交
2180
					dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked request "
2181 2182 2183 2184 2185
						   "done, calling scsi_done().\n",
						   HOSTNO, cmd->device->id, cmd->device->lun);
					cmd->scsi_done(cmd);
					cmd = hostdata->connected;
					break;
L
Linus Torvalds 已提交
2186
#endif /* def LINKED */
2187 2188 2189 2190
				case ABORT:
				case COMMAND_COMPLETE:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
H
Hannes Reinecke 已提交
2191
					dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d, lun %llu "
2192
						  "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
2193 2194 2195 2196

					local_irq_save(flags);
					hostdata->retain_dma_intr++;
					hostdata->connected = NULL;
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Linus Torvalds 已提交
2197
#ifdef SUPPORT_TAGS
2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208
					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. */
						TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
H
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2209
						dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu returned "
2210 2211 2212 2213 2214 2215
							   "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;
					}
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2216
#else
2217
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
L
Linus Torvalds 已提交
2218
#endif
2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241
					/* 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);
L
Linus Torvalds 已提交
2242

2243 2244 2245 2246 2247 2248
					if ((cmd->cmnd[0] == REQUEST_SENSE) &&
						hostdata->ses.cmd_len) {
						scsi_eh_restore_cmnd(cmd, &hostdata->ses);
						hostdata->ses.cmd_len = 0 ;
					}

2249 2250
					if ((cmd->cmnd[0] != REQUEST_SENSE) &&
					    (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2251 2252
						scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);

F
Finn Thain 已提交
2253
						dprintk(NDEBUG_AUTOSENSE, "scsi%d: performing request sense\n", HOSTNO);
2254 2255

						LIST(cmd,hostdata->issue_queue);
2256
						SET_NEXT(cmd, hostdata->issue_queue);
F
Finn Thain 已提交
2257
						hostdata->issue_queue = (struct scsi_cmnd *) cmd;
F
Finn Thain 已提交
2258
						dprintk(NDEBUG_QUEUES, "scsi%d: REQUEST SENSE added to head of "
2259
							  "issue queue\n", H_NO(cmd));
2260
					} else {
2261 2262 2263
						cmd->scsi_done(cmd);
					}

2264 2265
					local_irq_restore(flags);

2266 2267 2268 2269 2270 2271 2272 2273 2274 2275
					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();

2276
					local_irq_save(flags);
2277
					hostdata->retain_dma_intr--;
2278 2279 2280 2281
					/* ++roman: For Falcon SCSI, release the lock on the
					 * ST-DMA here if no other commands are waiting on the
					 * disconnected queue.
					 */
2282 2283
					maybe_release_dma_irq(instance);
					local_irq_restore(flags);
2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302
					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;
H
Hannes Reinecke 已提交
2303
						dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu rejected "
2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315
							   "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);
2316
					SET_NEXT(cmd, hostdata->disconnected_queue);
2317 2318 2319
					hostdata->connected = NULL;
					hostdata->disconnected_queue = cmd;
					local_irq_restore(flags);
H
Hannes Reinecke 已提交
2320
					dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d lun %llu was "
2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334
						  "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();
2335 2336 2337
#ifdef SUN3_SCSI_VME
					dregs->csr |= CSR_DMA_ENABLE;
#endif
2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372
					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);

F
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2373
					dprintk(NDEBUG_EXTENDED, "scsi%d: receiving extended message\n", HOSTNO);
2374 2375 2376 2377 2378

					len = 2;
					data = extended_msg + 1;
					phase = PHASE_MSGIN;
					NCR5380_transfer_pio(instance, &phase, &len, &data);
F
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2379
					dprintk(NDEBUG_EXTENDED, "scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390
						   (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);
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2391
						dprintk(NDEBUG_EXTENDED, "scsi%d: message received, residual %d\n",
2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418
							   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) {
F
Finn Thain 已提交
2419 2420
						printk(KERN_INFO "scsi%d: rejecting message ",
						       instance->host_no);
2421 2422 2423
						spi_print_msg(extended_msg);
						printk("\n");
					} else if (tmp != EXTENDED_MESSAGE)
F
Finn Thain 已提交
2424 2425 2426
						scmd_printk(KERN_INFO, cmd,
						            "rejecting unknown message %02x\n",
						            tmp);
2427
					else
F
Finn Thain 已提交
2428 2429 2430
						scmd_printk(KERN_INFO, cmd,
						            "rejecting unknown extended message code %02x, length %d\n",
						            extended_msg[1], extended_msg[0]);
2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442

					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) {
2443
					local_irq_save(flags);
L
Linus Torvalds 已提交
2444
#ifdef SUPPORT_TAGS
2445
					cmd_free_tag(cmd);
L
Linus Torvalds 已提交
2446
#else
2447
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
L
Linus Torvalds 已提交
2448
#endif
2449 2450 2451
					hostdata->connected = NULL;
					cmd->result = DID_ERROR << 16;
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2452 2453 2454
					maybe_release_dma_irq(instance);
					local_irq_restore(flags);
					cmd->scsi_done(cmd);
2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476
					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);
2477
				NCR5380_dprint(NDEBUG_ANY, instance);
2478 2479 2480
			} /* switch(phase) */
		} /* if (tmp * SR_REQ) */
	} /* while (1) */
L
Linus Torvalds 已提交
2481 2482 2483 2484 2485
}

/*
 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
 *
2486
 * Purpose : does reselection, initializing the instance->connected
F
Finn Thain 已提交
2487
 *	field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
L
Linus Torvalds 已提交
2488
 *	nexus has been reestablished,
2489
 *
L
Linus Torvalds 已提交
2490 2491 2492 2493 2494
 * Inputs : instance - this instance of the NCR5380.
 *
 */


2495 2496 2497
/* it might eventually prove necessary to do a dma setup on
   reselection, but it doesn't seem to be needed now -- sam */

2498
static void NCR5380_reselect(struct Scsi_Host *instance)
L
Linus Torvalds 已提交
2499
{
2500 2501
	SETUP_HOSTDATA(instance);
	unsigned char target_mask;
2502
	unsigned char lun;
L
Linus Torvalds 已提交
2503
#ifdef SUPPORT_TAGS
2504
	unsigned char tag;
L
Linus Torvalds 已提交
2505
#endif
2506
	unsigned char msg[3];
2507 2508
	int __maybe_unused len;
	unsigned char __maybe_unused *data, __maybe_unused phase;
F
Finn Thain 已提交
2509
	struct scsi_cmnd *tmp = NULL, *prev;
2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520

	/*
	 * 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);

F
Finn Thain 已提交
2521
	dprintk(NDEBUG_RESELECTION, "scsi%d: reselect\n", HOSTNO);
2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544

	/*
	 * 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))
		;

2545 2546 2547 2548 2549 2550 2551
#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
2552 2553 2554 2555
	len = 1;
	data = msg;
	phase = PHASE_MSGIN;
	NCR5380_transfer_pio(instance, &phase, &len, &data);
2556
#endif
2557 2558 2559 2560 2561 2562 2563 2564

	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);
L
Linus Torvalds 已提交
2565

2566
#if defined(SUPPORT_TAGS) && !defined(CONFIG_SUN3)
2567 2568 2569 2570 2571
	/* 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;
2572
	if (phase == PHASE_MSGIN && (hostdata->flags & FLAG_TAGGED_QUEUING)) {
2573 2574 2575 2576 2577 2578 2579
		/* 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];
F
Finn Thain 已提交
2580
		dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at "
2581 2582
			   "reselection\n", HOSTNO, target_mask, lun, tag);
	}
L
Linus Torvalds 已提交
2583
#endif
2584 2585 2586 2587 2588 2589

	/*
	 * 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.
	 */

F
Finn Thain 已提交
2590
	for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue, prev = NULL;
2591 2592
	     tmp; prev = tmp, tmp = NEXT(tmp)) {
		if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
L
Linus Torvalds 已提交
2593
#ifdef SUPPORT_TAGS
2594
		    && (tag == tmp->tag)
L
Linus Torvalds 已提交
2595
#endif
2596 2597 2598
		    ) {
			if (prev) {
				REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2599
				SET_NEXT(prev, NEXT(tmp));
2600 2601 2602 2603
			} else {
				REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
				hostdata->disconnected_queue = NEXT(tmp);
			}
2604
			SET_NEXT(tmp, NULL);
2605 2606
			break;
		}
L
Linus Torvalds 已提交
2607
	}
2608 2609 2610

	if (!tmp) {
		printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
L
Linus Torvalds 已提交
2611
#ifdef SUPPORT_TAGS
2612
		       "tag %d "
L
Linus Torvalds 已提交
2613
#endif
2614 2615
		       "not in disconnected_queue.\n",
		       HOSTNO, target_mask, lun
L
Linus Torvalds 已提交
2616
#ifdef SUPPORT_TAGS
2617
		       , tag
L
Linus Torvalds 已提交
2618
#endif
2619 2620 2621 2622 2623 2624 2625 2626
			);
		/*
		 * Since we have an established nexus that we can't do anything
		 * with, we must abort it.
		 */
		do_abort(instance);
		return;
	}
L
Linus Torvalds 已提交
2627

2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650
#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

2651 2652
	/* Accept message by clearing ACK */
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
L
Linus Torvalds 已提交
2653

2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672
#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

2673
	hostdata->connected = tmp;
H
Hannes Reinecke 已提交
2674
	dprintk(NDEBUG_RESELECTION, "scsi%d: nexus established, target = %d, lun = %llu, tag = %d\n",
2675
		   HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
L
Linus Torvalds 已提交
2676 2677 2678 2679
}


/*
F
Finn Thain 已提交
2680
 * Function : int NCR5380_abort (struct scsi_cmnd *cmd)
L
Linus Torvalds 已提交
2681 2682 2683
 *
 * Purpose : abort a command
 *
F
Finn Thain 已提交
2684
 * Inputs : cmd - the scsi_cmnd to abort, code - code to set the
2685
 *	host byte of the result field to, if zero DID_ABORTED is
L
Linus Torvalds 已提交
2686 2687
 *	used.
 *
2688
 * Returns : SUCCESS - success, FAILED on failure.
L
Linus Torvalds 已提交
2689
 *
2690 2691
 * XXX - there is no way to abort the command that is currently
 *	 connected, you have to wait for it to complete.  If this is
L
Linus Torvalds 已提交
2692
 *	 a problem, we could implement longjmp() / setjmp(), setjmp()
2693
 *	 called where the loop started in NCR5380_main().
L
Linus Torvalds 已提交
2694 2695 2696
 */

static
F
Finn Thain 已提交
2697
int NCR5380_abort(struct scsi_cmnd *cmd)
L
Linus Torvalds 已提交
2698
{
2699 2700
	struct Scsi_Host *instance = cmd->device->host;
	SETUP_HOSTDATA(instance);
F
Finn Thain 已提交
2701
	struct scsi_cmnd *tmp, **prev;
2702
	unsigned long flags;
L
Linus Torvalds 已提交
2703

2704
	scmd_printk(KERN_NOTICE, cmd, "aborting command\n");
L
Linus Torvalds 已提交
2705

2706 2707 2708
	NCR5380_print_status(instance);

	local_irq_save(flags);
L
Linus Torvalds 已提交
2709

F
Finn Thain 已提交
2710
	dprintk(NDEBUG_ABORT, "scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2711 2712
		    NCR5380_read(BUS_AND_STATUS_REG),
		    NCR5380_read(STATUS_REG));
L
Linus Torvalds 已提交
2713 2714

#if 1
2715 2716 2717 2718 2719
	/*
	 * 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.
	 */
L
Linus Torvalds 已提交
2720

2721
	if (hostdata->connected == cmd) {
L
Linus Torvalds 已提交
2722

F
Finn Thain 已提交
2723
		dprintk(NDEBUG_ABORT, "scsi%d: aborting connected command\n", HOSTNO);
2724 2725 2726 2727
		/*
		 * We should perform BSY checking, and make sure we haven't slipped
		 * into BUS FREE.
		 */
L
Linus Torvalds 已提交
2728

2729 2730 2731 2732 2733 2734
		/*	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.
		 */
L
Linus Torvalds 已提交
2735

2736 2737 2738 2739
		/*
		 * Return control to the executing NCR drive so we can clear the
		 * aborted flag and get back into our main loop.
		 */
L
Linus Torvalds 已提交
2740

2741 2742 2743 2744
		if (do_abort(instance) == 0) {
			hostdata->aborted = 1;
			hostdata->connected = NULL;
			cmd->result = DID_ABORT << 16;
L
Linus Torvalds 已提交
2745
#ifdef SUPPORT_TAGS
2746
			cmd_free_tag(cmd);
L
Linus Torvalds 已提交
2747
#else
2748
			hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
L
Linus Torvalds 已提交
2749
#endif
2750
			maybe_release_dma_irq(instance);
2751 2752
			local_irq_restore(flags);
			cmd->scsi_done(cmd);
2753
			return SUCCESS;
2754
		} else {
2755
			local_irq_restore(flags);
2756
			printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2757
			return FAILED;
2758 2759
		}
	}
L
Linus Torvalds 已提交
2760 2761
#endif

2762 2763 2764 2765
	/*
	 * Case 2 : If the command hasn't been issued yet, we simply remove it
	 *	    from the issue queue.
	 */
F
Finn Thain 已提交
2766 2767
	for (prev = (struct scsi_cmnd **)&(hostdata->issue_queue),
	     tmp = (struct scsi_cmnd *)hostdata->issue_queue;
2768 2769 2770 2771
	     tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
		if (cmd == tmp) {
			REMOVE(5, *prev, tmp, NEXT(tmp));
			(*prev) = NEXT(tmp);
2772
			SET_NEXT(tmp, NULL);
2773
			tmp->result = DID_ABORT << 16;
2774
			maybe_release_dma_irq(instance);
2775
			local_irq_restore(flags);
F
Finn Thain 已提交
2776
			dprintk(NDEBUG_ABORT, "scsi%d: abort removed command from issue queue.\n",
2777 2778 2779 2780
				    HOSTNO);
			/* Tagged queuing note: no tag to free here, hasn't been assigned
			 * yet... */
			tmp->scsi_done(tmp);
2781
			return SUCCESS;
2782
		}
L
Linus Torvalds 已提交
2783 2784
	}

2785 2786 2787 2788 2789 2790 2791 2792 2793 2794
	/*
	 * 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.
	 */
L
Linus Torvalds 已提交
2795

2796 2797
	if (hostdata->connected) {
		local_irq_restore(flags);
F
Finn Thain 已提交
2798
		dprintk(NDEBUG_ABORT, "scsi%d: abort failed, command connected.\n", HOSTNO);
2799
		return FAILED;
2800
	}
L
Linus Torvalds 已提交
2801

2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822 2823 2824 2825 2826
	/*
	 * 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.
	 */

F
Finn Thain 已提交
2827
	for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue; tmp;
2828 2829 2830
	     tmp = NEXT(tmp)) {
		if (cmd == tmp) {
			local_irq_restore(flags);
F
Finn Thain 已提交
2831
			dprintk(NDEBUG_ABORT, "scsi%d: aborting disconnected command.\n", HOSTNO);
2832

2833
			if (NCR5380_select(instance, cmd))
2834
				return FAILED;
L
Linus Torvalds 已提交
2835

F
Finn Thain 已提交
2836
			dprintk(NDEBUG_ABORT, "scsi%d: nexus reestablished.\n", HOSTNO);
2837 2838 2839 2840

			do_abort(instance);

			local_irq_save(flags);
F
Finn Thain 已提交
2841 2842
			for (prev = (struct scsi_cmnd **)&(hostdata->disconnected_queue),
			     tmp = (struct scsi_cmnd *)hostdata->disconnected_queue;
2843 2844 2845 2846
			     tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
				if (cmd == tmp) {
					REMOVE(5, *prev, tmp, NEXT(tmp));
					*prev = NEXT(tmp);
2847
					SET_NEXT(tmp, NULL);
2848 2849 2850 2851 2852
					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)
					 */
L
Linus Torvalds 已提交
2853
#ifdef SUPPORT_TAGS
2854
					cmd_free_tag(tmp);
L
Linus Torvalds 已提交
2855
#else
2856
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
L
Linus Torvalds 已提交
2857
#endif
2858
					maybe_release_dma_irq(instance);
2859 2860
					local_irq_restore(flags);
					tmp->scsi_done(tmp);
2861
					return SUCCESS;
2862 2863
				}
			}
L
Linus Torvalds 已提交
2864 2865 2866
		}
	}

2867 2868 2869 2870 2871 2872 2873
	/* 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);

2874 2875 2876 2877 2878 2879 2880 2881 2882
	/*
	 * 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.
	 */
L
Linus Torvalds 已提交
2883

2884
	printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO);
L
Linus Torvalds 已提交
2885

2886
	return FAILED;
L
Linus Torvalds 已提交
2887 2888 2889
}


2890
/*
F
Finn Thain 已提交
2891
 * Function : int NCR5380_reset (struct scsi_cmnd *cmd)
2892
 *
L
Linus Torvalds 已提交
2893 2894
 * Purpose : reset the SCSI bus.
 *
2895
 * Returns : SUCCESS or FAILURE
L
Linus Torvalds 已提交
2896
 *
2897
 */
L
Linus Torvalds 已提交
2898

F
Finn Thain 已提交
2899
static int NCR5380_bus_reset(struct scsi_cmnd *cmd)
L
Linus Torvalds 已提交
2900
{
2901 2902
	struct Scsi_Host *instance = cmd->device->host;
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
2903 2904
	int i;
	unsigned long flags;
2905
#if defined(RESET_RUN_DONE)
F
Finn Thain 已提交
2906
	struct scsi_cmnd *connected, *disconnected_queue;
L
Linus Torvalds 已提交
2907 2908
#endif

2909
	NCR5380_print_status(instance);
2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925

	/* 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);

2926 2927 2928 2929 2930 2931 2932 2933
	/* MSch 20140115 - looking at the generic NCR5380 driver, all of this
	 * should go.
	 * Catch-22: if we don't clear all queues, the SCSI driver lock will
	 * not be reset by atari_scsi_reset()!
	 */

#if defined(RESET_RUN_DONE)
	/* XXX Should now be done by midlevel code, but it's broken XXX */
2934 2935 2936 2937 2938 2939 2940 2941 2942 2943
	/* XXX see below                                            XXX */

	/* MSch: old-style reset: actually abort all command processing here */

	/* After the reset, there are no more connected or disconnected commands
	 * and no busy units; to avoid problems with re-inserting the commands
	 * into the issue_queue (via scsi_done()), the aborted commands are
	 * remembered in local variables first.
	 */
	local_irq_save(flags);
F
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2944
	connected = (struct scsi_cmnd *)hostdata->connected;
2945
	hostdata->connected = NULL;
F
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2946
	disconnected_queue = (struct scsi_cmnd *)hostdata->disconnected_queue;
2947
	hostdata->disconnected_queue = NULL;
L
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2948
#ifdef SUPPORT_TAGS
2949
	free_all_tags();
L
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2950
#endif
2951 2952
	for (i = 0; i < 8; ++i)
		hostdata->busy[i] = 0;
L
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2953
#ifdef REAL_DMA
2954
	hostdata->dma_len = 0;
L
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2955
#endif
2956
	local_irq_restore(flags);
L
Linus Torvalds 已提交
2957

2958 2959 2960 2961
	/* In order to tell the mid-level code which commands were aborted,
	 * set the command status to DID_RESET and call scsi_done() !!!
	 * This ultimately aborts processing of these commands in the mid-level.
	 */
L
Linus Torvalds 已提交
2962

2963
	if ((cmd = connected)) {
F
Finn Thain 已提交
2964
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd));
2965 2966 2967
		cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
		cmd->scsi_done(cmd);
	}
L
Linus Torvalds 已提交
2968

2969 2970
	for (i = 0; (cmd = disconnected_queue); ++i) {
		disconnected_queue = NEXT(cmd);
2971
		SET_NEXT(cmd, NULL);
2972 2973 2974 2975
		cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
		cmd->scsi_done(cmd);
	}
	if (i > 0)
F
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2976
		dprintk(NDEBUG_ABORT, "scsi: reset aborted %d disconnected command(s)\n", i);
L
Linus Torvalds 已提交
2977

2978 2979 2980 2981 2982 2983
	/* The Falcon lock should be released after a reset...
	 */
	/* ++guenther: moved to atari_scsi_reset(), to prevent a race between
	 * unlocking and enabling dma interrupt.
	 */
/*	falcon_release_lock_if_possible( hostdata );*/
L
Linus Torvalds 已提交
2984

2985 2986 2987 2988
	/* since all commands have been explicitly terminated, we need to tell
	 * the midlevel code that the reset was SUCCESSFUL, and there is no
	 * need to 'wake up' the commands by a request_sense
	 */
2989
	return SUCCESS;
L
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2990 2991
#else /* 1 */

2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015
	/* MSch: new-style reset handling: let the mid-level do what it can */

	/* ++guenther: MID-LEVEL IS STILL BROKEN.
	 * Mid-level is supposed to requeue all commands that were active on the
	 * various low-level queues. In fact it does this, but that's not enough
	 * because all these commands are subject to timeout. And if a timeout
	 * happens for any removed command, *_abort() is called but all queues
	 * are now empty. Abort then gives up the falcon lock, which is fatal,
	 * since the mid-level will queue more commands and must have the lock
	 * (it's all happening inside timer interrupt handler!!).
	 * Even worse, abort will return NOT_RUNNING for all those commands not
	 * on any queue, so they won't be retried ...
	 *
	 * Conclusion: either scsi.c disables timeout for all resetted commands
	 * immediately, or we lose!  As of linux-2.0.20 it doesn't.
	 */

	/* 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)
F
Finn Thain 已提交
3016
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
3017
	if (hostdata->connected)
F
Finn Thain 已提交
3018
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd));
3019
	if (hostdata->disconnected_queue)
F
Finn Thain 已提交
3020
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
3021 3022 3023 3024 3025

	local_irq_save(flags);
	hostdata->issue_queue = NULL;
	hostdata->connected = NULL;
	hostdata->disconnected_queue = NULL;
L
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3026
#ifdef SUPPORT_TAGS
3027
	free_all_tags(hostdata);
L
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3028
#endif
3029 3030
	for (i = 0; i < 8; ++i)
		hostdata->busy[i] = 0;
L
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3031
#ifdef REAL_DMA
3032
	hostdata->dma_len = 0;
L
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3033
#endif
3034 3035

	maybe_release_dma_irq(instance);
3036
	local_irq_restore(flags);
L
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3037

3038
	/* we did no complete reset of all commands, so a wakeup is required */
3039
	return SUCCESS;
L
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3040 3041
#endif /* 1 */
}