atari_NCR5380.c 90.5 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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 * DISTRIBUTION RELEASE 6.
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 *
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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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#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
 * Issues :
 *
 * The other Linux SCSI drivers were written when Linux was Intel PC-only,
 * and specifically for each board rather than each chip.  This makes their
 * adaptation to platforms like the Mac (Some of which use NCR5380's)
 * more difficult than it has to be.
 *
 * Also, many of the SCSI drivers were written before the command queuing
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 * routines were implemented, meaning their implementations of queued
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 * commands were hacked on rather than designed in from the start.
 *
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 * When I designed the Linux SCSI drivers I figured that
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 * while having two different SCSI boards in a system might be useful
 * for debugging things, two of the same type wouldn't be used.
 * Well, I was wrong and a number of users have mailed me about running
 * multiple high-performance SCSI boards in a server.
 *
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 * Finally, when I get questions from users, I have no idea what
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 * revision of my driver they are running.
 *
 * This driver attempts to address these problems :
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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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 * To solve the multiple-boards-in-the-same-system problem,
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 * there is a separate instance structure for each instance
 * of a 5380 in the system.  So, multiple NCR5380 drivers will
 * be able to coexist with appropriate changes to the high level
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 * SCSI code.
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 *
 * A NCR5380_PUBLIC_REVISION macro is provided, with the release
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 * number (updated for each public release) printed by the
 * NCR5380_print_options command, which should be called from the
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 * wrapper detect function, so that I know what release of the driver
 * users are using.
 *
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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,
 * which is started when not running by the interrupt handler,
 * timer, and queue command function.  It attempts to establish
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 * 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
 * queue, and NCR5380_main tries to find more work.  If USLEEP
 * was defined, and the target is idle for too long, the system
 * will try to sleep.
 *
 * If a command has disconnected, eventually an interrupt will trigger,
 * calling NCR5380_intr()  which will in turn call NCR5380_reselect
 * to reestablish a nexus.  This will run main if necessary.
 *
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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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 *
 * 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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 *
 * 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);
 *
 * If nothing specific to this implementation needs doing (ie, with external
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 * hardware), you must also define
 *
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 * NCR5380_queue_command
 * NCR5380_reset
 * NCR5380_abort
 * NCR5380_proc_info
 *
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 * to be the global entry points into the specific driver, ie
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 * #define NCR5380_queue_command t128_queue_command.
 *
 * If this is not done, the routines will be defined as static functions
 * with the NCR5380* names and the user must provide a globally
 * accessible wrapper function.
 *
 * 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,
 * possible) function may be used.  Before the specific driver initialization
 * code finishes, NCR5380_print_options should be called.
 */

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)		((Scsi_Cmnd *)(cmd)->host_scribble)
#define	SET_NEXT(cmd,next)	((cmd)->host_scribble = (void *)(next))
#define	NEXTADDR(cmd)		((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(void)
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{
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	int target, lun;
	TAG_ALLOC *ta;

	if (!setup_use_tagged_queuing)
		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(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 ||
	    !setup_use_tagged_queuing || !cmd->device->tagged_supported)
		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(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 ||
	    !setup_use_tagged_queuing || !cmd->device->tagged_supported) {
		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(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(void)
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{
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	int target, lun;
	TAG_ALLOC *ta;

	if (!setup_use_tagged_queuing)
		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 */


/*
 * Function: void merge_contiguous_buffers( Scsi_Cmnd *cmd )
 *
 * Purpose: Try to merge several scatter-gather requests into one DMA
 *    transfer. This is possible if the scatter buffers lie on
 *    physical contiguous addresses.
 *
 * Parameters: Scsi_Cmnd *cmd
 *    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(Scsi_Cmnd *cmd)
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{
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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
}

/*
 * Function : void initialize_SCp(Scsi_Cmnd *cmd)
 *
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 * Purpose : initialize the saved data pointers for cmd to point to the
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 *	start of the buffer.
 *
 * Inputs : cmd - Scsi_Cmnd structure to have pointers reset.
 */

506
static inline void initialize_SCp(Scsi_Cmnd *cmd)
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{
508 509 510
	/*
	 * Initialize the Scsi Pointer field so that all of the commands in the
	 * various queues are valid.
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	 */
512

513 514 515
	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);
517 518 519 520 521 522 523 524
		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;
525 526
		cmd->SCp.ptr = NULL;
		cmd->SCp.this_residual = 0;
527
	}
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}

#include <linux/delay.h>

#if NDEBUG
static struct {
534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554
	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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/*
 * Function : void NCR5380_print(struct Scsi_Host *instance)
 *
 * Purpose : print the SCSI bus signals for debugging purposes
 *
 * Input : instance - which NCR5380
 */

564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592
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 {
596 597
	unsigned char value;
	const char *name;
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} phases[] = {
599 600 601 602
	{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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604
/*
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 * Function : void NCR5380_print_phase(struct Scsi_Host *instance)
 *
 * Purpose : print the current SCSI phase for debugging purposes
 *
 * Input : instance - which NCR5380
 */

static void NCR5380_print_phase(struct Scsi_Host *instance)
{
614 615 616 617 618 619 620 621 622 623 624 625
	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()
632
 *
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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.
 */

643
#include <linux/gfp.h>
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#include <linux/workqueue.h>
#include <linux/interrupt.h>

647
static volatile int main_running;
648
static DECLARE_WORK(NCR5380_tqueue, NCR5380_main);
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650
static inline void queue_main(void)
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{
652 653 654 655 656 657 658 659 660
	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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}


664
static inline void NCR5380_all_init(void)
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{
666 667
	static int done = 0;
	if (!done) {
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		dprintk(NDEBUG_INIT, "scsi : NCR5380_all_init()\n");
669 670
		done = 1;
	}
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}

673

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/*
 * Function : void NCR58380_print_options (struct Scsi_Host *instance)
 *
 * Purpose : called by probe code indicating the NCR5380 driver
 *	     options that were selected.
 *
 * Inputs : instance, pointer to this instance.  Unused.
 */

683
static void __init NCR5380_print_options(struct Scsi_Host *instance)
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{
685 686 687
	printk(" generic options"
#ifdef AUTOSENSE
	       " AUTOSENSE"
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#endif
#ifdef REAL_DMA
690
	       " REAL DMA"
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#endif
#ifdef PARITY
693
	       " PARITY"
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#endif
#ifdef SUPPORT_TAGS
696
	       " SCSI-2 TAGGED QUEUING"
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#endif
698 699
	       );
	printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
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}

/*
 * Function : void NCR5380_print_status (struct Scsi_Host *instance)
 *
 * Purpose : print commands in the various queues, called from
 *	NCR5380_abort and NCR5380_debug to aid debugging.
 *
708
 * Inputs : instance, pointer to this instance.
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 */

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static void lprint_Scsi_Cmnd(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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{
727 728 729
	struct NCR5380_hostdata *hostdata;
	Scsi_Cmnd *ptr;
	unsigned long flags;
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731 732
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
733 734 735

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

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	printk("\nNCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
737
	local_irq_save(flags);
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	printk("NCR5380: coroutine is%s running.\n",
739 740
		main_running ? "" : "n't");
	if (!hostdata->connected)
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		printk("scsi%d: no currently connected command\n", HOSTNO);
742
	else
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		lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected);
	printk("scsi%d: issue_queue\n", HOSTNO);
	for (ptr = (Scsi_Cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr))
		lprint_Scsi_Cmnd(ptr);
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	printk("scsi%d: disconnected_queue\n", HOSTNO);
749
	for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr;
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	     ptr = NEXT(ptr))
		lprint_Scsi_Cmnd(ptr);
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753
	local_irq_restore(flags);
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	printk("\n");
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}

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static void show_Scsi_Cmnd(Scsi_Cmnd *cmd, struct seq_file *m)
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{
759 760
	int i, s;
	unsigned char *command;
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	seq_printf(m, "scsi%d: destination target %d, lun %llu\n",
762
		H_NO(cmd), cmd->device->id, cmd->device->lun);
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	seq_printf(m, "        command = ");
764
	command = cmd->cmnd;
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	seq_printf(m, "%2d (0x%02x)", command[0], command[0]);
766
	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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}

771 772
static int __maybe_unused NCR5380_show_info(struct seq_file *m,
                                            struct Scsi_Host *instance)
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{
	struct NCR5380_hostdata *hostdata;
	Scsi_Cmnd *ptr;
	unsigned long flags;

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

	seq_printf(m, "NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
	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
		show_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, m);
	seq_printf(m, "scsi%d: issue_queue\n", HOSTNO);
	for (ptr = (Scsi_Cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr))
		show_Scsi_Cmnd(ptr, m);

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

	local_irq_restore(flags);
	return 0;
}
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801
/*
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 * Function : void NCR5380_init (struct Scsi_Host *instance)
 *
 * Purpose : initializes *instance and corresponding 5380 chip.
 *
806
 * Inputs : instance - instantiation of the 5380 driver.
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 *
 * Notes : I assume that the host, hostno, and id bits have been
809 810
 *	set correctly.  I don't care about the irq and other fields.
 *
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 */

813
static int __init NCR5380_init(struct Scsi_Host *instance, int flags)
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{
815 816 817 818 819 820 821 822 823 824 825 826 827
	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
829
	init_tags();
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#endif
#if defined (REAL_DMA)
832
	hostdata->dma_len = 0;
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#endif
834 835 836 837 838 839 840 841 842 843
	hostdata->targets_present = 0;
	hostdata->connected = NULL;
	hostdata->issue_queue = NULL;
	hostdata->disconnected_queue = NULL;
	hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT;

	if (!the_template) {
		the_template = instance->hostt;
		first_instance = instance;
	}
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#ifndef AUTOSENSE
846 847 848 849
	if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1))
		printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n"
		       "        without AUTOSENSE option, contingent allegiance conditions may\n"
		       "        be incorrectly cleared.\n", HOSTNO);
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#endif /* def AUTOSENSE */

852 853 854 855
	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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857
	return 0;
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}

860 861 862 863 864
static void NCR5380_exit(struct Scsi_Host *instance)
{
	/* Empty, as we didn't schedule any delayed work */
}

865 866 867
/*
 * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd,
 *	void (*done)(Scsi_Cmnd *))
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 *
 * Purpose :  enqueues a SCSI command
 *
 * Inputs : cmd - SCSI command, done - function called on completion, with
 *	a pointer to the command descriptor.
873
 *
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 * Returns : 0
 *
876 877 878
 * Side effects :
 *      cmd is added to the per instance issue_queue, with minor
 *	twiddling done to the host specific fields of cmd.  If the
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 *	main coroutine is not running, it is restarted.
 *
 */

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static int NCR5380_queue_command_lck(Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
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{
885 886 887
	SETUP_HOSTDATA(cmd->device->host);
	Scsi_Cmnd *tmp;
	unsigned long flags;
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#if (NDEBUG & NDEBUG_NO_WRITE)
890 891 892 893 894 895 896 897 898
	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);
		done(cmd);
		return 0;
	}
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#endif /* (NDEBUG & NDEBUG_NO_WRITE) */

#ifdef NCR5380_STATS
# if 0
903 904 905 906
	if (!hostdata->connected && !hostdata->issue_queue &&
	    !hostdata->disconnected_queue) {
		hostdata->timebase = jiffies;
	}
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# endif
# ifdef NCR5380_STAT_LIMIT
909
	if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT)
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# endif
911 912 913 914 915
		switch (cmd->cmnd[0]) {
		case WRITE:
		case WRITE_6:
		case WRITE_10:
			hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
916
			hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);
917 918 919 920 921 922
			hostdata->pendingw++;
			break;
		case READ:
		case READ_6:
		case READ_10:
			hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
923
			hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);
924 925 926
			hostdata->pendingr++;
			break;
		}
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#endif

929 930 931 932 933
	/*
	 * We use the host_scribble field as a pointer to the next command
	 * in a queue
	 */

934
	SET_NEXT(cmd, NULL);
935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959
	cmd->scsi_done = done;

	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.
	 */

	local_irq_save(flags);
	/* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
	 * Otherwise a running NCR5380_main may steal the lock.
	 * Lock before actually inserting due to fairness reasons explained in
	 * atari_scsi.c. If we insert first, then it's impossible for this driver
	 * to release the lock.
	 * Stop timer for this command while waiting for the lock, or timeouts
	 * may happen (and they really do), and it's no good if the command doesn't
	 * appear in any of the queues.
	 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
	 * because also a timer int can trigger an abort or reset, which would
	 * alter queues and touch the lock.
	 */
	if (!IS_A_TT()) {
960
		/* perhaps stop command timer here */
961
		falcon_get_lock();
962
		/* perhaps restart command timer here */
963 964 965
	}
	if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
		LIST(cmd, hostdata->issue_queue);
966
		SET_NEXT(cmd, hostdata->issue_queue);
967 968 969 970 971 972
		hostdata->issue_queue = cmd;
	} else {
		for (tmp = (Scsi_Cmnd *)hostdata->issue_queue;
		     NEXT(tmp); tmp = NEXT(tmp))
			;
		LIST(cmd, tmp);
973
		SET_NEXT(tmp, cmd);
974 975 976
	}
	local_irq_restore(flags);

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	dprintk(NDEBUG_QUEUES, "scsi%d: command added to %s of queue\n", H_NO(cmd),
978 979 980 981 982 983 984 985 986 987 988 989 990 991
		  (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");

	/* If queue_command() is called from an interrupt (real one or bottom
	 * half), we let queue_main() do the job of taking care about main. If it
	 * is already running, this is a no-op, else main will be queued.
	 *
	 * If we're not in an interrupt, we can call NCR5380_main()
	 * unconditionally, because it cannot be already running.
	 */
	if (in_interrupt() || ((flags >> 8) & 7) >= 6)
		queue_main();
	else
		NCR5380_main(NULL);
	return 0;
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}

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static DEF_SCSI_QCMD(NCR5380_queue_command)

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/*
997
 * Function : NCR5380_main (void)
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 *
999 1000 1001
 * Purpose : 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
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 *	in case it is not running.
1003 1004
 *
 * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
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 *  reenable them.  This prevents reentrancy and kernel stack overflow.
1006 1007
 */

1008
static void NCR5380_main(struct work_struct *work)
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{
1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046
	Scsi_Cmnd *tmp, *prev;
	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);
1048 1049 1050 1051
			/*
			 * Search through the issue_queue for a command destined
			 * for a target that's not busy.
			 */
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#if (NDEBUG & NDEBUG_LISTS)
1053 1054 1055 1056 1057 1058 1059
			for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL;
			     tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
				;
			/*printk("%p  ", tmp);*/
			if ((tmp == prev) && tmp)
				printk(" LOOP\n");
			/* else printk("\n"); */
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#endif
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			for (tmp = (Scsi_Cmnd *) hostdata->issue_queue,
			     prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) {
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				u8 lun = tmp->device->lun;
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#if (NDEBUG & NDEBUG_LISTS)
1066
				if (prev != tmp)
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					printk("MAIN tmp=%p   target=%d   busy=%d lun=%llu\n",
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					       tmp, tmp->device->id, hostdata->busy[tmp->device->id],
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					       lun);
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#endif
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				/*  When we find one, remove it from the issue queue. */
				/* ++guenther: possible race with Falcon locking */
				if (
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#ifdef SUPPORT_TAGS
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				    !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
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#else
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				    !(hostdata->busy[tmp->device->id] & (1 << lun))
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#endif
1079 1080 1081 1082 1083
				    ) {
					/* ++guenther: just to be sure, this must be atomic */
					local_irq_disable();
					if (prev) {
						REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1084
						SET_NEXT(prev, NEXT(tmp));
1085 1086 1087 1088
					} else {
						REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
						hostdata->issue_queue = NEXT(tmp);
					}
1089
					SET_NEXT(tmp, NULL);
1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100
					falcon_dont_release++;

					/* 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.
					 */
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					dprintk(NDEBUG_MAIN, "scsi%d: main(): command for target %d "
1102
						    "lun %d removed from issue_queue\n",
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						    HOSTNO, tmp->device->id, lun);
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					/*
					 * 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
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					cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE);
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#endif
1117
					if (!NCR5380_select(instance, tmp)) {
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						falcon_dont_release--;
						/* release if target did not response! */
						falcon_release_lock_if_possible(hostdata);
						break;
					} else {
						local_irq_disable();
						LIST(tmp, hostdata->issue_queue);
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						SET_NEXT(tmp, hostdata->issue_queue);
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						hostdata->issue_queue = tmp;
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#ifdef SUPPORT_TAGS
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						cmd_free_tag(tmp);
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#endif
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						falcon_dont_release--;
						local_irq_restore(flags);
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						dprintk(NDEBUG_MAIN, "scsi%d: main(): select() failed, "
1133 1134 1135 1136 1137 1138 1139 1140 1141
							    "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
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		    && !hostdata->dma_len
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#endif
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		    ) {
			local_irq_restore(flags);
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			dprintk(NDEBUG_MAIN, "scsi%d: main: performing information transfer\n",
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				    HOSTNO);
			NCR5380_information_transfer(instance);
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			dprintk(NDEBUG_MAIN, "scsi%d: main: done set false\n", HOSTNO);
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			done = 0;
		}
	} while (!done);
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	/* 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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}


#ifdef REAL_DMA
/*
 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
 *
 * Purpose : Called by interrupt handler when DMA finishes or a phase
1168
 *	mismatch occurs (which would finish the DMA transfer).
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 *
 * Inputs : instance - this instance of the NCR5380.
 *
 */

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static void NCR5380_dma_complete(struct Scsi_Host *instance)
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{
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	SETUP_HOSTDATA(instance);
	int transfered, saved_data = 0, overrun = 0, cnt, toPIO;
	unsigned char **data, p;
	volatile int *count;

	if (!hostdata->connected) {
		printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
		       "no connected cmd\n", HOSTNO);
		return;
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	}
1186 1187 1188 1189 1190 1191 1192 1193 1194 1195

	if (atari_read_overruns) {
		p = hostdata->connected->SCp.phase;
		if (p & SR_IO) {
			udelay(10);
			if ((NCR5380_read(BUS_AND_STATUS_REG) &
			     (BASR_PHASE_MATCH|BASR_ACK)) ==
			    (BASR_PHASE_MATCH|BASR_ACK)) {
				saved_data = NCR5380_read(INPUT_DATA_REG);
				overrun = 1;
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				dprintk(NDEBUG_DMA, "scsi%d: read overrun handled\n", HOSTNO);
1197 1198 1199 1200
			}
		}
	}

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	dprintk(NDEBUG_DMA, "scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220
		   HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
		   NCR5380_read(STATUS_REG));

	(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;

	if (atari_read_overruns) {
		if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
			cnt = toPIO = atari_read_overruns;
			if (overrun) {
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				dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n");
1222 1223 1224 1225 1226
				*(*data)++ = saved_data;
				(*count)--;
				cnt--;
				toPIO--;
			}
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			dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
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			NCR5380_transfer_pio(instance, &p, &cnt, data);
			*count -= toPIO - cnt;
		}
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	}
}
#endif /* REAL_DMA */


/*
 * Function : void NCR5380_intr (int irq)
1238
 *
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 * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1240
 *	from the disconnected queue, and restarting NCR5380_main()
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 *	as required.
 *
 * Inputs : int irq, irq that caused this interrupt.
 *
 */

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static irqreturn_t NCR5380_intr(int irq, void *dev_id)
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{
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	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);
1254 1255 1256

	/* Look for pending interrupts */
	basr = NCR5380_read(BUS_AND_STATUS_REG);
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	dprintk(NDEBUG_INTR, "scsi%d: BASR=%02x\n", HOSTNO, basr);
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	/* dispatch to appropriate routine if found and done=0 */
	if (basr & BASR_IRQ) {
1260
		NCR5380_dprint(NDEBUG_INTR, instance);
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		if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
			done = 0;
			ENABLE_IRQ();
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			dprintk(NDEBUG_INTR, "scsi%d: SEL interrupt\n", HOSTNO);
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			NCR5380_reselect(instance);
			(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
		} else if (basr & BASR_PARITY_ERROR) {
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			dprintk(NDEBUG_INTR, "scsi%d: PARITY interrupt\n", HOSTNO);
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			(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
		} else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
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			dprintk(NDEBUG_INTR, "scsi%d: RESET interrupt\n", HOSTNO);
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			(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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#if defined(REAL_DMA)
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			/*
			 * 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))) {

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				dprintk(NDEBUG_INTR, "scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
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				NCR5380_dma_complete( instance );
				done = 0;
				ENABLE_IRQ();
			} else
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#endif /* REAL_DMA */
1296
			{
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/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
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				if (basr & BASR_PHASE_MATCH)
					printk(KERN_NOTICE "scsi%d: unknown interrupt, "
					       "BASR 0x%x, MR 0x%x, SR 0x%x\n",
					       HOSTNO, basr, NCR5380_read(MODE_REG),
					       NCR5380_read(STATUS_REG));
				(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
			}
		} /* 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);
	}

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

#ifdef NCR5380_STATS
1323
static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd *cmd)
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{
# ifdef NCR5380_STAT_LIMIT
1326
	if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT)
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# endif
1328 1329 1330 1331 1332
		switch (cmd->cmnd[0]) {
		case WRITE:
		case WRITE_6:
		case WRITE_10:
			hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase);
1333
			/*hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);*/
1334 1335 1336 1337 1338 1339
			hostdata->pendingw--;
			break;
		case READ:
		case READ_6:
		case READ_10:
			hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase);
1340
			/*hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);*/
1341 1342 1343
			hostdata->pendingr--;
			break;
		}
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}
#endif

1347
/*
1348
 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd)
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 *
 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1351 1352
 *	including ARBITRATION, SELECTION, and initial message out for
 *	IDENTIFY and queue messages.
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 *
1354
 * Inputs : instance - instantiation of the 5380 driver on which this
1355
 *	target lives, cmd - SCSI command to execute.
1356
 *
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 * Returns : -1 if selection could not execute for some reason,
1358 1359
 *	0 if selection succeeded or failed because the target
 *	did not respond.
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 *
1361 1362
 * Side effects :
 *	If bus busy, arbitration failed, etc, NCR5380_select() will exit
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 *		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.
 *
1367 1368 1369
 *	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.
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 *
1371
 *	If failed (no target) : cmd->scsi_done() will be called, and the
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 *		cmd->result host byte set to DID_BAD_TARGET.
 */

1375
static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd *cmd)
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{
1377 1378 1379 1380 1381 1382 1383 1384
	SETUP_HOSTDATA(instance);
	unsigned char tmp[3], phase;
	unsigned char *data;
	int len;
	unsigned long timeout;
	unsigned long flags;

	hostdata->restart_select = 0;
1385
	NCR5380_dprint(NDEBUG_ARBITRATION, instance);
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	dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", HOSTNO,
1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399
		   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);
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1401 1402 1403
	/*
	 * Start arbitration.
	 */
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1405 1406
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
	NCR5380_write(MODE_REG, MR_ARBITRATE);
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1408
	local_irq_restore(flags);
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1410
	/* Wait for arbitration logic to complete */
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#if defined(NCR_TIMEOUT)
1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424
	{
		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;
		}
	}
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#else /* NCR_TIMEOUT */
1426 1427 1428
	while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
	       !hostdata->connected)
		;
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#endif

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	dprintk(NDEBUG_ARBITRATION, "scsi%d: arbitration complete\n", HOSTNO);
1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451

	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);
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		dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1453 1454 1455
			   HOSTNO);
		return -1;
	}
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1457 1458 1459 1460 1461 1462 1463 1464 1465 1466
	/* 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);
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		dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1468 1469 1470 1471 1472 1473 1474 1475
			   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
1478 1479
	/* ++roman: But some targets (see above :-) seem to need a bit more... */
	udelay(15);
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#else
1481
	udelay(2);
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#endif
1483 1484 1485 1486 1487 1488 1489

	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);
1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506

	/*
	 * 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);

1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519
	/*
	 * 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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1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546
	/*
	 * 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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1548
	udelay(1);
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	dprintk(NDEBUG_SELECTION, "scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
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1552 1553 1554 1555
	/*
	 * The SCSI specification calls for a 250 ms timeout for the actual
	 * selection.
	 */
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1557
	timeout = jiffies + 25;
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1559 1560 1561 1562 1563
	/*
	 * 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
1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584
	/* ++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
1586 1587
	while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY))
		;
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#endif

1590 1591 1592 1593 1594
	/*
	 * 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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1596
	udelay(1);
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1598
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
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1600 1601 1602 1603 1604 1605
	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");
1606
			NCR5380_dprint(NDEBUG_ANY, instance);
1607 1608 1609 1610
			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
			return -1;
		}
		cmd->result = DID_BAD_TARGET << 16;
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#ifdef NCR5380_STATS
1612
		collect_stats(hostdata, cmd);
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#endif
#ifdef SUPPORT_TAGS
1615
		cmd_free_tag(cmd);
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#endif
1617 1618
		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);
1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644
		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",
1646 1647
		   HOSTNO, cmd->device->id);
	tmp[0] = IDENTIFY(1, cmd->device->lun);
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#ifdef SUPPORT_TAGS
1650 1651 1652 1653 1654 1655
	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
1657 1658
	len = 1;
	cmd->tag = 0;
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#endif /* SUPPORT_TAGS */

1661 1662 1663 1664
	/* 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);
1666 1667
	/* XXX need to handle errors here */
	hostdata->connected = cmd;
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#ifndef SUPPORT_TAGS
1669 1670
	hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
#endif
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1672
	initialize_SCp(cmd);
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1674
	return 0;
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}

1677 1678
/*
 * 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
 *
1683 1684
 * 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.
1686
 *
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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.
 *
1691
 *	Also, *phase, *count, *data are modified in place.
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 *
 * XXX Note : handling for bus free may be useful.
 */

/*
1697
 * 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.
 */

1702 1703 1704
static int NCR5380_transfer_pio(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
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{
1706 1707 1708 1709 1710 1711 1712 1713
	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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	 */

1716
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
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1718 1719 1720 1721 1722 1723 1724
	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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1728 1729
		/* Check for phase mismatch */
		if ((tmp & PHASE_MASK) != p) {
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			dprintk(NDEBUG_PIO, "scsi%d: phase mismatch\n", HOSTNO);
1731
			NCR5380_dprint_phase(NDEBUG_PIO, instance);
1732 1733
			break;
		}
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1735 1736 1737 1738 1739
		/* 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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1741
		++d;
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1743 1744 1745 1746 1747 1748
		/*
		 * 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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1750 1751 1752
		if (!(p & SR_IO)) {
			if (!((p & SR_MSG) && c > 1)) {
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1753
				NCR5380_dprint(NDEBUG_PIO, instance);
1754 1755 1756 1757 1758
				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);
1759
				NCR5380_dprint(NDEBUG_PIO, instance);
1760 1761 1762 1763
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
					      ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
			}
		} else {
1764
			NCR5380_dprint(NDEBUG_PIO, instance);
1765 1766
			NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
		}
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1768 1769 1770
		while (NCR5380_read(STATUS_REG) & SR_REQ)
			;

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		dprintk(NDEBUG_HANDSHAKE, "scsi%d: req false, handshake complete\n", HOSTNO);
1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791

		/*
		 * 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);
1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809

	*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)
1814 1815 1816 1817
 *
 * 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.
 */

1821
static int do_abort(struct Scsi_Host *host)
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{
1823 1824 1825 1826
	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);
1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838

	/*
	 * 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.
	 */

1839
	while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863
		;

	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)
1867 1868
/*
 * 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.
 *
1874 1875
 * 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.
1877
 *
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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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1880 1881
 *	is in same phase.
 *
1882
 *	Also, *phase, *count, *data are modified in place.
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 *
 */


1887 1888 1889
static int NCR5380_transfer_dma(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
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{
1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901
	SETUP_HOSTDATA(instance);
	register int c = *count;
	register unsigned char p = *phase;
	register unsigned char *d = *data;
	unsigned char tmp;
	unsigned long flags;

	if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
		*phase = tmp;
		return -1;
	}
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1903 1904
	if (atari_read_overruns && (p & SR_IO))
		c -= atari_read_overruns;
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	dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1907 1908
		   HOSTNO, (p & SR_IO) ? "reading" : "writing",
		   c, (p & SR_IO) ? "to" : "from", d);
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1910
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
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#ifdef REAL_DMA
1913
	NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
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#endif /* def REAL_DMA  */

1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944
	if (IS_A_TT()) {
		/* On the Medusa, it is a must to initialize the DMA before
		 * starting the NCR. This is also the cleaner way for the TT.
		 */
		local_irq_save(flags);
		hostdata->dma_len = (p & SR_IO) ?
			NCR5380_dma_read_setup(instance, d, c) :
			NCR5380_dma_write_setup(instance, d, c);
		local_irq_restore(flags);
	}

	if (p & SR_IO)
		NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
	else {
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
		NCR5380_write(START_DMA_SEND_REG, 0);
	}

	if (!IS_A_TT()) {
		/* 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);
	}
	return 0;
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}
#endif /* defined(REAL_DMA) */

/*
 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
 *
1951 1952
 * Purpose : run through the various SCSI phases and do as the target
 *	directs us to.  Operates on the currently connected command,
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1953 1954 1955 1956
 *	instance->connected.
 *
 * Inputs : instance, instance for which we are doing commands
 *
1957
 * Side effects : SCSI things happen, the disconnected queue will be
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 *	modified if a command disconnects, *instance->connected will
 *	change.
 *
1961 1962
 * XXX Note : we need to watch for bus free or a reset condition here
 *	to recover from an unexpected bus free condition.
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 */
1964 1965

static void NCR5380_information_transfer(struct Scsi_Host *instance)
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{
1967 1968 1969 1970 1971
	SETUP_HOSTDATA(instance);
	unsigned long flags;
	unsigned char msgout = NOP;
	int sink = 0;
	int len;
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#if defined(REAL_DMA)
1973
	int transfersize;
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#endif
1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985
	unsigned char *data;
	unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
	Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;

	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;
1986
				NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
1987
			}
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1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
			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:
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Linus Torvalds 已提交
2004
#if (NDEBUG & NDEBUG_NO_DATAOUT)
2005 2006 2007 2008 2009
				printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
				       "aborted\n", HOSTNO);
				sink = 1;
				do_abort(instance);
				cmd->result = DID_ERROR << 16;
2010
				cmd->scsi_done(cmd);
2011
				return;
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Linus Torvalds 已提交
2012
#endif
2013 2014 2015 2016 2017 2018 2019 2020 2021 2022
			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
2023
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2024 2025 2026 2027
					/* ++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
2028
					dprintk(NDEBUG_INFORMATION, "scsi%d: %d bytes and %d buffers left\n",
2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046
						   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.
				 */
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Linus Torvalds 已提交
2047 2048

#if defined(REAL_DMA)
2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059
				if (!cmd->device->borken &&
				    (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) {
					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. */
						printk(KERN_NOTICE "scsi%d: switching target %d "
H
Hannes Reinecke 已提交
2060
							   "lun %llu to slow handshake\n", HOSTNO,
2061 2062 2063 2064 2065 2066 2067
							   cmd->device->id, cmd->device->lun);
						cmd->device->borken = 1;
						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
							ICR_ASSERT_ATN);
						sink = 1;
						do_abort(instance);
						cmd->result = DID_ERROR << 16;
2068
						cmd->scsi_done(cmd);
2069 2070
						/* XXX - need to source or sink data here, as appropriate */
					} else {
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2071
#ifdef REAL_DMA
2072 2073 2074 2075 2076 2077 2078 2079
						/* ++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;
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Linus Torvalds 已提交
2080
#endif
2081 2082
					}
				} else
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2083
#endif /* defined(REAL_DMA) */
2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105
					NCR5380_transfer_pio(instance, &phase,
							     (int *)&cmd->SCp.this_residual,
							     (unsigned char **)&cmd->SCp.ptr);
				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.
				 */
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Linus Torvalds 已提交
2106
#ifdef LINKED
2107 2108 2109 2110 2111
				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
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					dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked command "
2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123
						   "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) {
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Hannes Reinecke 已提交
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						 printk(KERN_NOTICE "scsi%d: target %d lun %llu "
2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136
							"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);
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					dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked request "
2138 2139
						   "done, calling scsi_done().\n",
						   HOSTNO, cmd->device->id, cmd->device->lun);
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#ifdef NCR5380_STATS
2141
					collect_stats(hostdata, cmd);
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2142
#endif
2143 2144 2145
					cmd->scsi_done(cmd);
					cmd = hostdata->connected;
					break;
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2146
#endif /* def LINKED */
2147 2148 2149 2150 2151 2152 2153
				case ABORT:
				case COMMAND_COMPLETE:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
					/* ++guenther: possible race with Falcon locking */
					falcon_dont_release++;
					hostdata->connected = NULL;
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2154
					dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d, lun %llu "
2155
						  "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
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2156
#ifdef SUPPORT_TAGS
2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167
					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];
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Hannes Reinecke 已提交
2168
						dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu returned "
2169 2170 2171 2172 2173 2174
							   "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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2175
#else
2176
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
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2177
#endif
2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200
					/* 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);
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Linus Torvalds 已提交
2201

2202
#ifdef AUTOSENSE
2203 2204 2205 2206 2207 2208
					if ((cmd->cmnd[0] == REQUEST_SENSE) &&
						hostdata->ses.cmd_len) {
						scsi_eh_restore_cmnd(cmd, &hostdata->ses);
						hostdata->ses.cmd_len = 0 ;
					}

2209 2210
					if ((cmd->cmnd[0] != REQUEST_SENSE) &&
					    (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2211 2212
						scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);

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Finn Thain 已提交
2213
						dprintk(NDEBUG_AUTOSENSE, "scsi%d: performing request sense\n", HOSTNO);
2214 2215 2216

						local_irq_save(flags);
						LIST(cmd,hostdata->issue_queue);
2217
						SET_NEXT(cmd, hostdata->issue_queue);
2218 2219
						hostdata->issue_queue = (Scsi_Cmnd *) cmd;
						local_irq_restore(flags);
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						dprintk(NDEBUG_QUEUES, "scsi%d: REQUEST SENSE added to head of "
2221 2222
							  "issue queue\n", H_NO(cmd));
					} else
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2223
#endif /* def AUTOSENSE */
2224
					{
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2225
#ifdef NCR5380_STATS
2226
						collect_stats(hostdata, cmd);
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2227
#endif
2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265
						cmd->scsi_done(cmd);
					}

					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();

					falcon_dont_release--;
					/* ++roman: For Falcon SCSI, release the lock on the
					 * ST-DMA here if no other commands are waiting on the
					 * disconnected queue.
					 */
					falcon_release_lock_if_possible(hostdata);
					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;
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2266
						dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu rejected "
2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278
							   "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);
2279
					SET_NEXT(cmd, hostdata->disconnected_queue);
2280 2281 2282
					hostdata->connected = NULL;
					hostdata->disconnected_queue = cmd;
					local_irq_restore(flags);
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2283
					dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d lun %llu was "
2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332
						  "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();
					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);

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2333
					dprintk(NDEBUG_EXTENDED, "scsi%d: receiving extended message\n", HOSTNO);
2334 2335 2336 2337 2338

					len = 2;
					data = extended_msg + 1;
					phase = PHASE_MSGIN;
					NCR5380_transfer_pio(instance, &phase, &len, &data);
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2339
					dprintk(NDEBUG_EXTENDED, "scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350
						   (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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2351
						dprintk(NDEBUG_EXTENDED, "scsi%d: message received, residual %d\n",
2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383
							   HOSTNO, len);

						switch (extended_msg[2]) {
						case EXTENDED_SDTR:
						case EXTENDED_WDTR:
						case EXTENDED_MODIFY_DATA_POINTER:
						case EXTENDED_EXTENDED_IDENTIFY:
							tmp = 0;
						}
					} else if (len) {
						printk(KERN_NOTICE "scsi%d: error receiving "
						       "extended message\n", HOSTNO);
						tmp = 0;
					} else {
						printk(KERN_NOTICE "scsi%d: extended message "
							   "code %02x length %d is too long\n",
							   HOSTNO, extended_msg[2], extended_msg[1]);
						tmp = 0;
					}
					/* Fall through to reject message */

					/*
					 * If we get something weird that we aren't expecting,
					 * reject it.
					 */
				default:
					if (!tmp) {
						printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO);
						spi_print_msg(extended_msg);
						printk("\n");
					} else if (tmp != EXTENDED_MESSAGE)
						printk(KERN_DEBUG "scsi%d: rejecting unknown "
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2384
						       "message %02x from target %d, lun %llu\n",
2385 2386 2387 2388
						       HOSTNO, tmp, cmd->device->id, cmd->device->lun);
					else
						printk(KERN_DEBUG "scsi%d: rejecting unknown "
						       "extended message "
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2389
						       "code %02x, length %d from target %d, lun %llu\n",
2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404
						       HOSTNO, extended_msg[1], extended_msg[0],
						       cmd->device->id, cmd->device->lun);


					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) {
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2405
#ifdef SUPPORT_TAGS
2406
					cmd_free_tag(cmd);
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2407
#else
2408
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
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2409
#endif
2410 2411
					hostdata->connected = NULL;
					cmd->result = DID_ERROR << 16;
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2412
#ifdef NCR5380_STATS
2413
					collect_stats(hostdata, cmd);
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2414
#endif
2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439
					cmd->scsi_done(cmd);
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
					falcon_release_lock_if_possible(hostdata);
					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);
2440
				NCR5380_dprint(NDEBUG_ANY, instance);
2441 2442 2443
			} /* switch(phase) */
		} /* if (tmp * SR_REQ) */
	} /* while (1) */
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2444 2445 2446 2447 2448
}

/*
 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
 *
2449 2450
 * Purpose : does reselection, initializing the instance->connected
 *	field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
L
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2451
 *	nexus has been reestablished,
2452
 *
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2453 2454 2455 2456 2457
 * Inputs : instance - this instance of the NCR5380.
 *
 */


2458
static void NCR5380_reselect(struct Scsi_Host *instance)
L
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2459
{
2460 2461 2462 2463
	SETUP_HOSTDATA(instance);
	unsigned char target_mask;
	unsigned char lun, phase;
	int len;
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2464
#ifdef SUPPORT_TAGS
2465
	unsigned char tag;
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2466
#endif
2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481
	unsigned char msg[3];
	unsigned char *data;
	Scsi_Cmnd *tmp = NULL, *prev;
/*	unsigned long flags; */

	/*
	 * 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
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2482
	dprintk(NDEBUG_RESELECTION, "scsi%d: reselect\n", HOSTNO);
2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517

	/*
	 * 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))
		;

	len = 1;
	data = msg;
	phase = PHASE_MSGIN;
	NCR5380_transfer_pio(instance, &phase, &len, &data);

	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
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2518 2519

#ifdef SUPPORT_TAGS
2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532
	/* 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];
F
Finn Thain 已提交
2533
		dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at "
2534 2535
			   "reselection\n", HOSTNO, target_mask, lun, tag);
	}
L
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2536
#endif
2537 2538 2539 2540 2541 2542 2543 2544 2545

	/*
	 * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we
	 * just reestablished, and remove it from the disconnected queue.
	 */

	for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL;
	     tmp; prev = tmp, tmp = NEXT(tmp)) {
		if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
L
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2546
#ifdef SUPPORT_TAGS
2547
		    && (tag == tmp->tag)
L
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2548
#endif
2549 2550 2551 2552 2553
		    ) {
			/* ++guenther: prevent race with falcon_release_lock */
			falcon_dont_release++;
			if (prev) {
				REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2554
				SET_NEXT(prev, NEXT(tmp));
2555 2556 2557 2558
			} else {
				REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
				hostdata->disconnected_queue = NEXT(tmp);
			}
2559
			SET_NEXT(tmp, NULL);
2560 2561
			break;
		}
L
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2562
	}
2563 2564 2565

	if (!tmp) {
		printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
L
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2566
#ifdef SUPPORT_TAGS
2567
		       "tag %d "
L
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2568
#endif
2569 2570
		       "not in disconnected_queue.\n",
		       HOSTNO, target_mask, lun
L
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2571
#ifdef SUPPORT_TAGS
2572
		       , tag
L
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2573
#endif
2574 2575 2576 2577 2578 2579 2580 2581
			);
		/*
		 * Since we have an established nexus that we can't do anything
		 * with, we must abort it.
		 */
		do_abort(instance);
		return;
	}
L
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2582

2583 2584
	/* Accept message by clearing ACK */
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
L
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2585

2586
	hostdata->connected = tmp;
H
Hannes Reinecke 已提交
2587
	dprintk(NDEBUG_RESELECTION, "scsi%d: nexus established, target = %d, lun = %llu, tag = %d\n",
2588 2589
		   HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
	falcon_dont_release--;
L
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2590 2591 2592 2593 2594 2595 2596 2597
}


/*
 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
 *
 * Purpose : abort a command
 *
2598 2599
 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
 *	host byte of the result field to, if zero DID_ABORTED is
L
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2600 2601
 *	used.
 *
2602
 * Returns : SUCCESS - success, FAILED on failure.
L
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2603
 *
2604 2605
 * 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
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2606
 *	 a problem, we could implement longjmp() / setjmp(), setjmp()
2607
 *	 called where the loop started in NCR5380_main().
L
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2608 2609 2610
 */

static
2611
int NCR5380_abort(Scsi_Cmnd *cmd)
L
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2612
{
2613 2614 2615 2616
	struct Scsi_Host *instance = cmd->device->host;
	SETUP_HOSTDATA(instance);
	Scsi_Cmnd *tmp, **prev;
	unsigned long flags;
L
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2617

2618
	scmd_printk(KERN_NOTICE, cmd, "aborting command\n");
L
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2619

2620 2621 2622
	NCR5380_print_status(instance);

	local_irq_save(flags);
L
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2623

2624 2625 2626
	if (!IS_A_TT() && !falcon_got_lock)
		printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n",
		       HOSTNO);
L
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2627

F
Finn Thain 已提交
2628
	dprintk(NDEBUG_ABORT, "scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2629 2630
		    NCR5380_read(BUS_AND_STATUS_REG),
		    NCR5380_read(STATUS_REG));
L
Linus Torvalds 已提交
2631 2632

#if 1
2633 2634 2635 2636 2637
	/*
	 * 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
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2638

2639
	if (hostdata->connected == cmd) {
L
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2640

F
Finn Thain 已提交
2641
		dprintk(NDEBUG_ABORT, "scsi%d: aborting connected command\n", HOSTNO);
2642 2643 2644 2645
		/*
		 * We should perform BSY checking, and make sure we haven't slipped
		 * into BUS FREE.
		 */
L
Linus Torvalds 已提交
2646

2647 2648 2649 2650 2651 2652
		/*	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
2653

2654 2655 2656 2657
		/*
		 * 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
2658

2659 2660 2661 2662
		if (do_abort(instance) == 0) {
			hostdata->aborted = 1;
			hostdata->connected = NULL;
			cmd->result = DID_ABORT << 16;
L
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2663
#ifdef SUPPORT_TAGS
2664
			cmd_free_tag(cmd);
L
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2665
#else
2666
			hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
L
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2667
#endif
2668 2669 2670
			local_irq_restore(flags);
			cmd->scsi_done(cmd);
			falcon_release_lock_if_possible(hostdata);
2671
			return SUCCESS;
2672 2673 2674
		} else {
/*			local_irq_restore(flags); */
			printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2675
			return FAILED;
2676 2677
		}
	}
L
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2678 2679
#endif

2680 2681 2682 2683 2684 2685 2686 2687 2688 2689
	/*
	 * Case 2 : If the command hasn't been issued yet, we simply remove it
	 *	    from the issue queue.
	 */
	for (prev = (Scsi_Cmnd **)&(hostdata->issue_queue),
	     tmp = (Scsi_Cmnd *)hostdata->issue_queue;
	     tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
		if (cmd == tmp) {
			REMOVE(5, *prev, tmp, NEXT(tmp));
			(*prev) = NEXT(tmp);
2690
			SET_NEXT(tmp, NULL);
2691 2692
			tmp->result = DID_ABORT << 16;
			local_irq_restore(flags);
F
Finn Thain 已提交
2693
			dprintk(NDEBUG_ABORT, "scsi%d: abort removed command from issue queue.\n",
2694 2695 2696 2697 2698
				    HOSTNO);
			/* Tagged queuing note: no tag to free here, hasn't been assigned
			 * yet... */
			tmp->scsi_done(tmp);
			falcon_release_lock_if_possible(hostdata);
2699
			return SUCCESS;
2700
		}
L
Linus Torvalds 已提交
2701 2702
	}

2703 2704 2705 2706 2707 2708 2709 2710 2711 2712
	/*
	 * 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
2713

2714 2715
	if (hostdata->connected) {
		local_irq_restore(flags);
F
Finn Thain 已提交
2716
		dprintk(NDEBUG_ABORT, "scsi%d: abort failed, command connected.\n", HOSTNO);
2717
		return FAILED;
2718
	}
L
Linus Torvalds 已提交
2719

2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748
	/*
	 * Case 4: If the command is currently disconnected from the bus, and
	 *	there are no connected commands, we reconnect the I_T_L or
	 *	I_T_L_Q nexus associated with it, go into message out, and send
	 *      an abort message.
	 *
	 * This case is especially ugly. In order to reestablish the nexus, we
	 * need to call NCR5380_select().  The easiest way to implement this
	 * function was to abort if the bus was busy, and let the interrupt
	 * handler triggered on the SEL for reselect take care of lost arbitrations
	 * where necessary, meaning interrupts need to be enabled.
	 *
	 * When interrupts are enabled, the queues may change - so we
	 * can't remove it from the disconnected queue before selecting it
	 * because that could cause a failure in hashing the nexus if that
	 * device reselected.
	 *
	 * Since the queues may change, we can't use the pointers from when we
	 * first locate it.
	 *
	 * So, we must first locate the command, and if NCR5380_select()
	 * succeeds, then issue the abort, relocate the command and remove
	 * it from the disconnected queue.
	 */

	for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp;
	     tmp = NEXT(tmp)) {
		if (cmd == tmp) {
			local_irq_restore(flags);
F
Finn Thain 已提交
2749
			dprintk(NDEBUG_ABORT, "scsi%d: aborting disconnected command.\n", HOSTNO);
2750

2751
			if (NCR5380_select(instance, cmd))
2752
				return FAILED;
L
Linus Torvalds 已提交
2753

F
Finn Thain 已提交
2754
			dprintk(NDEBUG_ABORT, "scsi%d: nexus reestablished.\n", HOSTNO);
2755 2756 2757 2758 2759 2760 2761 2762 2763 2764

			do_abort(instance);

			local_irq_save(flags);
			for (prev = (Scsi_Cmnd **)&(hostdata->disconnected_queue),
			     tmp = (Scsi_Cmnd *)hostdata->disconnected_queue;
			     tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
				if (cmd == tmp) {
					REMOVE(5, *prev, tmp, NEXT(tmp));
					*prev = NEXT(tmp);
2765
					SET_NEXT(tmp, NULL);
2766 2767 2768 2769 2770
					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
2771
#ifdef SUPPORT_TAGS
2772
					cmd_free_tag(tmp);
L
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2773
#else
2774
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
L
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2775
#endif
2776 2777 2778
					local_irq_restore(flags);
					tmp->scsi_done(tmp);
					falcon_release_lock_if_possible(hostdata);
2779
					return SUCCESS;
2780 2781
				}
			}
L
Linus Torvalds 已提交
2782 2783 2784
		}
	}

2785 2786 2787 2788 2789 2790 2791 2792 2793
	/*
	 * 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
2794

2795
	local_irq_restore(flags);
2796
	printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO);
L
Linus Torvalds 已提交
2797

2798 2799 2800 2801 2802
	/* 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.
	 */
	falcon_release_lock_if_possible(hostdata);
L
Linus Torvalds 已提交
2803

2804
	return FAILED;
L
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2805 2806 2807
}


2808
/*
L
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2809
 * Function : int NCR5380_reset (Scsi_Cmnd *cmd)
2810
 *
L
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2811 2812
 * Purpose : reset the SCSI bus.
 *
2813
 * Returns : SUCCESS or FAILURE
L
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2814
 *
2815
 */
L
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2816

2817
static int NCR5380_bus_reset(Scsi_Cmnd *cmd)
L
Linus Torvalds 已提交
2818
{
2819 2820 2821
	SETUP_HOSTDATA(cmd->device->host);
	int i;
	unsigned long flags;
2822
#if defined(RESET_RUN_DONE)
2823
	Scsi_Cmnd *connected, *disconnected_queue;
L
Linus Torvalds 已提交
2824 2825
#endif

2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846
	if (!IS_A_TT() && !falcon_got_lock)
		printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n",
		       H_NO(cmd));

	NCR5380_print_status(cmd->device->host);

	/* 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);

2847 2848 2849 2850 2851 2852 2853 2854
	/* 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 */
2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868
	/* 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);
	connected = (Scsi_Cmnd *)hostdata->connected;
	hostdata->connected = NULL;
	disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue;
	hostdata->disconnected_queue = NULL;
L
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2869
#ifdef SUPPORT_TAGS
2870
	free_all_tags();
L
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2871
#endif
2872 2873
	for (i = 0; i < 8; ++i)
		hostdata->busy[i] = 0;
L
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2874
#ifdef REAL_DMA
2875
	hostdata->dma_len = 0;
L
Linus Torvalds 已提交
2876
#endif
2877
	local_irq_restore(flags);
L
Linus Torvalds 已提交
2878

2879 2880 2881 2882
	/* 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
2883

2884
	if ((cmd = connected)) {
F
Finn Thain 已提交
2885
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd));
2886 2887 2888
		cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
		cmd->scsi_done(cmd);
	}
L
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2889

2890 2891
	for (i = 0; (cmd = disconnected_queue); ++i) {
		disconnected_queue = NEXT(cmd);
2892
		SET_NEXT(cmd, NULL);
2893 2894 2895 2896
		cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
		cmd->scsi_done(cmd);
	}
	if (i > 0)
F
Finn Thain 已提交
2897
		dprintk(NDEBUG_ABORT, "scsi: reset aborted %d disconnected command(s)\n", i);
L
Linus Torvalds 已提交
2898

2899 2900 2901 2902 2903 2904
	/* 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
2905

2906 2907 2908 2909
	/* 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
	 */
2910
	return SUCCESS;
L
Linus Torvalds 已提交
2911 2912
#else /* 1 */

2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936
	/* 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
2937
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2938
	if (hostdata->connected)
F
Finn Thain 已提交
2939
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd));
2940
	if (hostdata->disconnected_queue)
F
Finn Thain 已提交
2941
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
2942 2943 2944 2945 2946

	local_irq_save(flags);
	hostdata->issue_queue = NULL;
	hostdata->connected = NULL;
	hostdata->disconnected_queue = NULL;
L
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2947
#ifdef SUPPORT_TAGS
2948
	free_all_tags();
L
Linus Torvalds 已提交
2949
#endif
2950 2951
	for (i = 0; i < 8; ++i)
		hostdata->busy[i] = 0;
L
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2952
#ifdef REAL_DMA
2953
	hostdata->dma_len = 0;
L
Linus Torvalds 已提交
2954
#endif
2955
	local_irq_restore(flags);
L
Linus Torvalds 已提交
2956

2957
	/* we did no complete reset of all commands, so a wakeup is required */
2958
	return SUCCESS;
L
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2959 2960
#endif /* 1 */
}