atari_NCR5380.c 88.5 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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 * 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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 *
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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
 *
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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,
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 * possible) function may be used.
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 */

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

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#define	NEXT(cmd)		((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.
 */

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static inline void initialize_SCp(Scsi_Cmnd *cmd)
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{
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	/*
	 * Initialize the Scsi Pointer field so that all of the commands in the
	 * various queues are valid.
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	 */
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	if (scsi_bufflen(cmd)) {
		cmd->SCp.buffer = scsi_sglist(cmd);
		cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
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		cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
507 508 509 510 511 512 513 514
		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;
515 516
		cmd->SCp.ptr = NULL;
		cmd->SCp.this_residual = 0;
517
	}
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}

#include <linux/delay.h>

#if NDEBUG
static struct {
524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544
	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
 */

554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582
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 {
586 587
	unsigned char value;
	const char *name;
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} phases[] = {
589 590 591 592
	{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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594
/*
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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)
{
604 605 606 607 608 609 610 611 612 613 614 615
	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()
622
 *
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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.
 */

633
#include <linux/gfp.h>
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#include <linux/workqueue.h>
#include <linux/interrupt.h>

637
static volatile int main_running;
638
static DECLARE_WORK(NCR5380_tqueue, NCR5380_main);
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640
static inline void queue_main(void)
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{
642 643 644 645 646 647 648 649 650
	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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}


654
static inline void NCR5380_all_init(void)
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{
656 657
	static int done = 0;
	if (!done) {
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		dprintk(NDEBUG_INIT, "scsi : NCR5380_all_init()\n");
659 660
		done = 1;
	}
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}

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

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static const char *NCR5380_info(struct Scsi_Host *instance)
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{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);

	return hostdata->info;
}

static void prepare_info(struct Scsi_Host *instance)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);

	snprintf(hostdata->info, sizeof(hostdata->info),
	         "%s, io_port 0x%lx, n_io_port %d, "
	         "base 0x%lx, irq %d, "
	         "can_queue %d, cmd_per_lun %d, "
	         "sg_tablesize %d, this_id %d, "
	         "options { %s} ",
	         instance->hostt->name, instance->io_port, instance->n_io_port,
	         instance->base, instance->irq,
	         instance->can_queue, instance->cmd_per_lun,
	         instance->sg_tablesize, instance->this_id,
#ifdef DIFFERENTIAL
	         "DIFFERENTIAL "
#endif
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#ifdef REAL_DMA
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	         "REAL_DMA "
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#endif
#ifdef PARITY
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	         "PARITY "
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#endif
#ifdef SUPPORT_TAGS
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	         "SUPPORT_TAGS "
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#endif
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	         "");
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}

/*
 * 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.
 *
714
 * 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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{
733 734 735
	struct NCR5380_hostdata *hostdata;
	Scsi_Cmnd *ptr;
	unsigned long flags;
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737 738
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
739 740 741 742

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

	local_irq_save(flags);
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	printk("NCR5380: coroutine is%s running.\n",
744 745
		main_running ? "" : "n't");
	if (!hostdata->connected)
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		printk("scsi%d: no currently connected command\n", HOSTNO);
747
	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);
754
	for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr;
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	     ptr = NEXT(ptr))
		lprint_Scsi_Cmnd(ptr);
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758
	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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{
764 765
	int i, s;
	unsigned char *command;
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	seq_printf(m, "scsi%d: destination target %d, lun %llu\n",
767
		H_NO(cmd), cmd->device->id, cmd->device->lun);
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	seq_printf(m, "        command = ");
769
	command = cmd->cmnd;
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	seq_printf(m, "%2d (0x%02x)", command[0], command[0]);
771
	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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}

776 777
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;

	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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805
/*
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 * Function : void NCR5380_init (struct Scsi_Host *instance)
 *
 * Purpose : initializes *instance and corresponding 5380 chip.
 *
810
 * Inputs : instance - instantiation of the 5380 driver.
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 *
 * Notes : I assume that the host, hostno, and id bits have been
813 814
 *	set correctly.  I don't care about the irq and other fields.
 *
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 */

817
static int __init NCR5380_init(struct Scsi_Host *instance, int flags)
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{
819 820 821 822 823 824 825 826 827 828 829 830 831
	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
833
	init_tags();
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#endif
#if defined (REAL_DMA)
836
	hostdata->dma_len = 0;
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#endif
838 839 840 841 842 843 844 845 846 847
	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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	prepare_info(instance);

851 852 853 854
	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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856
	return 0;
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}

859 860 861 862 863
static void NCR5380_exit(struct Scsi_Host *instance)
{
	/* Empty, as we didn't schedule any delayed work */
}

864 865 866
/*
 * 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.
872
 *
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 * Returns : 0
 *
875 876 877
 * 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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{
884 885 886
	SETUP_HOSTDATA(cmd->device->host);
	Scsi_Cmnd *tmp;
	unsigned long flags;
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#if (NDEBUG & NDEBUG_NO_WRITE)
889 890 891 892 893 894 895 896 897
	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) */

900 901 902 903 904
	/*
	 * We use the host_scribble field as a pointer to the next command
	 * in a queue
	 */

905
	SET_NEXT(cmd, NULL);
906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930
	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()) {
931
		/* perhaps stop command timer here */
932
		falcon_get_lock();
933
		/* perhaps restart command timer here */
934 935 936
	}
	if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
		LIST(cmd, hostdata->issue_queue);
937
		SET_NEXT(cmd, hostdata->issue_queue);
938 939 940 941 942 943
		hostdata->issue_queue = cmd;
	} else {
		for (tmp = (Scsi_Cmnd *)hostdata->issue_queue;
		     NEXT(tmp); tmp = NEXT(tmp))
			;
		LIST(cmd, tmp);
944
		SET_NEXT(tmp, cmd);
945 946 947
	}
	local_irq_restore(flags);

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	dprintk(NDEBUG_QUEUES, "scsi%d: command added to %s of queue\n", H_NO(cmd),
949 950 951 952 953 954 955 956 957 958 959 960 961 962
		  (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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/*
968
 * Function : NCR5380_main (void)
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 *
970 971 972
 * 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.
974 975
 *
 * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
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 *  reenable them.  This prevents reentrancy and kernel stack overflow.
977 978
 */

979
static void NCR5380_main(struct work_struct *work)
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{
981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017
	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);
1019 1020 1021 1022
			/*
			 * Search through the issue_queue for a command destined
			 * for a target that's not busy.
			 */
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1023
#if (NDEBUG & NDEBUG_LISTS)
1024 1025 1026 1027 1028 1029 1030
			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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1031
#endif
1032 1033
			for (tmp = (Scsi_Cmnd *) hostdata->issue_queue,
			     prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) {
H
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1034
				u8 lun = tmp->device->lun;
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1035 1036

#if (NDEBUG & NDEBUG_LISTS)
1037
				if (prev != tmp)
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1038
					printk("MAIN tmp=%p   target=%d   busy=%d lun=%llu\n",
1039
					       tmp, tmp->device->id, hostdata->busy[tmp->device->id],
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1040
					       lun);
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1041
#endif
1042 1043 1044
				/*  When we find one, remove it from the issue queue. */
				/* ++guenther: possible race with Falcon locking */
				if (
L
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1045
#ifdef SUPPORT_TAGS
1046
				    !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
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1047
#else
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1048
				    !(hostdata->busy[tmp->device->id] & (1 << lun))
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1049
#endif
1050 1051 1052 1053 1054
				    ) {
					/* ++guenther: just to be sure, this must be atomic */
					local_irq_disable();
					if (prev) {
						REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1055
						SET_NEXT(prev, NEXT(tmp));
1056 1057 1058 1059
					} else {
						REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
						hostdata->issue_queue = NEXT(tmp);
					}
1060
					SET_NEXT(tmp, NULL);
1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071
					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 "
1073
						    "lun %d removed from issue_queue\n",
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1074
						    HOSTNO, tmp->device->id, lun);
1075 1076 1077 1078 1079 1080 1081 1082 1083 1084
					/*
					 * 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
1086
					cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE);
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1087
#endif
1088
					if (!NCR5380_select(instance, tmp)) {
1089 1090 1091 1092 1093 1094 1095
						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);
1096
						SET_NEXT(tmp, hostdata->issue_queue);
1097
						hostdata->issue_queue = tmp;
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#ifdef SUPPORT_TAGS
1099
						cmd_free_tag(tmp);
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1100
#endif
1101 1102
						falcon_dont_release--;
						local_irq_restore(flags);
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						dprintk(NDEBUG_MAIN, "scsi%d: main(): select() failed, "
1104 1105 1106 1107 1108 1109 1110 1111 1112
							    "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
1114
		    && !hostdata->dma_len
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1115
#endif
1116 1117
		    ) {
			local_irq_restore(flags);
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			dprintk(NDEBUG_MAIN, "scsi%d: main: performing information transfer\n",
1119 1120
				    HOSTNO);
			NCR5380_information_transfer(instance);
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1121
			dprintk(NDEBUG_MAIN, "scsi%d: main: done set false\n", HOSTNO);
1122 1123 1124
			done = 0;
		}
	} while (!done);
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1126 1127 1128 1129 1130
	/* 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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1131 1132 1133 1134 1135 1136 1137 1138
}


#ifdef REAL_DMA
/*
 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
 *
 * Purpose : Called by interrupt handler when DMA finishes or a phase
1139
 *	mismatch occurs (which would finish the DMA transfer).
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 *
 * Inputs : instance - this instance of the NCR5380.
 *
 */

1145
static void NCR5380_dma_complete(struct Scsi_Host *instance)
L
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1146
{
1147 1148 1149 1150 1151 1152 1153 1154 1155
	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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1156
	}
1157 1158 1159 1160 1161 1162 1163 1164 1165 1166

	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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1167
				dprintk(NDEBUG_DMA, "scsi%d: read overrun handled\n", HOSTNO);
1168 1169 1170 1171
			}
		}
	}

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	dprintk(NDEBUG_DMA, "scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191
		   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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1192
				dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n");
1193 1194 1195 1196 1197
				*(*data)++ = saved_data;
				(*count)--;
				cnt--;
				toPIO--;
			}
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			dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
1199 1200 1201
			NCR5380_transfer_pio(instance, &p, &cnt, data);
			*count -= toPIO - cnt;
		}
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1202 1203 1204 1205 1206 1207 1208
	}
}
#endif /* REAL_DMA */


/*
 * Function : void NCR5380_intr (int irq)
1209
 *
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 * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1211
 *	from the disconnected queue, and restarting NCR5380_main()
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 *	as required.
 *
 * Inputs : int irq, irq that caused this interrupt.
 *
 */

1218
static irqreturn_t NCR5380_intr(int irq, void *dev_id)
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{
1220 1221 1222 1223
	struct Scsi_Host *instance = first_instance;
	int done = 1, handled = 0;
	unsigned char basr;

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1224
	dprintk(NDEBUG_INTR, "scsi%d: NCR5380 irq triggered\n", HOSTNO);
1225 1226 1227

	/* 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);
1229 1230
	/* dispatch to appropriate routine if found and done=0 */
	if (basr & BASR_IRQ) {
1231
		NCR5380_dprint(NDEBUG_INTR, instance);
1232 1233 1234
		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);
1236 1237 1238
			NCR5380_reselect(instance);
			(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
		} else if (basr & BASR_PARITY_ERROR) {
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1239
			dprintk(NDEBUG_INTR, "scsi%d: PARITY interrupt\n", HOSTNO);
1240 1241
			(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);
1243 1244 1245 1246 1247 1248
			(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)
1251 1252 1253 1254 1255 1256 1257 1258 1259 1260
			/*
			 * 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);
1262 1263 1264 1265
				NCR5380_dma_complete( instance );
				done = 0;
				ENABLE_IRQ();
			} else
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#endif /* REAL_DMA */
1267
			{
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/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285
				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);
1287 1288 1289 1290
		/* Put a call to NCR5380_main() on the queue... */
		queue_main();
	}
	return IRQ_RETVAL(handled);
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}

1293
/*
1294
 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd)
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1295 1296
 *
 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1297 1298
 *	including ARBITRATION, SELECTION, and initial message out for
 *	IDENTIFY and queue messages.
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1299
 *
1300
 * Inputs : instance - instantiation of the 5380 driver on which this
1301
 *	target lives, cmd - SCSI command to execute.
1302
 *
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1303
 * Returns : -1 if selection could not execute for some reason,
1304 1305
 *	0 if selection succeeded or failed because the target
 *	did not respond.
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1306
 *
1307 1308
 * Side effects :
 *	If bus busy, arbitration failed, etc, NCR5380_select() will exit
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1309 1310 1311 1312
 *		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.
 *
1313 1314 1315
 *	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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1316
 *
1317
 *	If failed (no target) : cmd->scsi_done() will be called, and the
L
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1318 1319 1320
 *		cmd->result host byte set to DID_BAD_TARGET.
 */

1321
static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd *cmd)
L
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1322
{
1323 1324 1325 1326 1327 1328 1329 1330
	SETUP_HOSTDATA(instance);
	unsigned char tmp[3], phase;
	unsigned char *data;
	int len;
	unsigned long timeout;
	unsigned long flags;

	hostdata->restart_select = 0;
1331
	NCR5380_dprint(NDEBUG_ARBITRATION, instance);
F
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1332
	dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", HOSTNO,
1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345
		   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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1346

1347 1348 1349
	/*
	 * Start arbitration.
	 */
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1350

1351 1352
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
	NCR5380_write(MODE_REG, MR_ARBITRATE);
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1353

1354
	local_irq_restore(flags);
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1355

1356
	/* Wait for arbitration logic to complete */
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1357
#if defined(NCR_TIMEOUT)
1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370
	{
		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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1371
#else /* NCR_TIMEOUT */
1372 1373 1374
	while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
	       !hostdata->connected)
		;
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1375 1376
#endif

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1377
	dprintk(NDEBUG_ARBITRATION, "scsi%d: arbitration complete\n", HOSTNO);
1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397

	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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1398
		dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1399 1400 1401
			   HOSTNO);
		return -1;
	}
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1403 1404 1405 1406 1407 1408 1409 1410 1411 1412
	/* after/during arbitration, BSY should be asserted.
	   IBM DPES-31080 Version S31Q works now */
	/* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
	NCR5380_write(INITIATOR_COMMAND_REG,
		      ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY);

	if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
	    hostdata->connected) {
		NCR5380_write(MODE_REG, MR_BASE);
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
F
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1413
		dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1414 1415 1416 1417 1418 1419 1420 1421
			   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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1422 1423

#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1424 1425
	/* ++roman: But some targets (see above :-) seem to need a bit more... */
	udelay(15);
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1426
#else
1427
	udelay(2);
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1428
#endif
1429 1430 1431 1432 1433 1434 1435

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

F
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1436
	dprintk(NDEBUG_ARBITRATION, "scsi%d: won arbitration\n", HOSTNO);
1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452

	/*
	 * 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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1453 1454
	NCR5380_write(MODE_REG, MR_BASE);

1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465
	/*
	 * 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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1466

1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492
	/*
	 * 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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1494
	udelay(1);
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1495

F
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1496
	dprintk(NDEBUG_SELECTION, "scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
L
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1497

1498 1499 1500 1501
	/*
	 * The SCSI specification calls for a 250 ms timeout for the actual
	 * selection.
	 */
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1502

1503
	timeout = jiffies + 25;
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1504

1505 1506 1507 1508 1509
	/*
	 * 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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1510 1511

#if 0
1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530
	/* ++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
1532 1533
	while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY))
		;
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1534 1535
#endif

1536 1537 1538 1539 1540
	/*
	 * 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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1542
	udelay(1);
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1543

1544
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
L
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1545

1546 1547 1548 1549 1550 1551
	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");
1552
			NCR5380_dprint(NDEBUG_ANY, instance);
1553 1554 1555 1556
			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
			return -1;
		}
		cmd->result = DID_BAD_TARGET << 16;
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1557
#ifdef SUPPORT_TAGS
1558
		cmd_free_tag(cmd);
L
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1559
#endif
1560 1561
		cmd->scsi_done(cmd);
		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
F
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1562
		dprintk(NDEBUG_SELECTION, "scsi%d: target did not respond within 250ms\n", HOSTNO);
1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587
		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",
1589 1590
		   HOSTNO, cmd->device->id);
	tmp[0] = IDENTIFY(1, cmd->device->lun);
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1591 1592

#ifdef SUPPORT_TAGS
1593 1594 1595 1596 1597 1598
	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
1600 1601
	len = 1;
	cmd->tag = 0;
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1602 1603
#endif /* SUPPORT_TAGS */

1604 1605 1606 1607
	/* Send message(s) */
	data = tmp;
	phase = PHASE_MSGOUT;
	NCR5380_transfer_pio(instance, &phase, &len, &data);
F
Finn Thain 已提交
1608
	dprintk(NDEBUG_SELECTION, "scsi%d: nexus established.\n", HOSTNO);
1609 1610
	/* XXX need to handle errors here */
	hostdata->connected = cmd;
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1611
#ifndef SUPPORT_TAGS
1612 1613
	hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
#endif
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1614

1615
	initialize_SCp(cmd);
L
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1616

1617
	return 0;
L
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1618 1619
}

1620 1621
/*
 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
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1622 1623 1624 1625
 *      unsigned char *phase, int *count, unsigned char **data)
 *
 * Purpose : transfers data in given phase using polled I/O
 *
1626 1627
 * Inputs : instance - instance of driver, *phase - pointer to
 *	what phase is expected, *count - pointer to number of
L
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1628
 *	bytes to transfer, **data - pointer to data pointer.
1629
 *
L
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1630
 * Returns : -1 when different phase is entered without transferring
L
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1631
 *	maximum number of bytes, 0 if all bytes are transferred or exit
L
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1632 1633
 *	is in same phase.
 *
1634
 *	Also, *phase, *count, *data are modified in place.
L
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1635 1636 1637 1638 1639
 *
 * XXX Note : handling for bus free may be useful.
 */

/*
1640
 * Note : this code is not as quick as it could be, however it
L
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1641 1642 1643 1644
 * IS 100% reliable, and for the actual data transfer where speed
 * counts, we will always do a pseudo DMA or DMA transfer.
 */

1645 1646 1647
static int NCR5380_transfer_pio(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
L
Linus Torvalds 已提交
1648
{
1649 1650 1651 1652 1653 1654 1655 1656
	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
L
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1657 1658
	 */

1659
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
L
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1660

1661 1662 1663 1664 1665 1666 1667
	do {
		/*
		 * Wait for assertion of REQ, after which the phase bits will be
		 * valid
		 */
		while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
			;
L
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F
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1669
		dprintk(NDEBUG_HANDSHAKE, "scsi%d: REQ detected\n", HOSTNO);
L
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1670

1671 1672
		/* Check for phase mismatch */
		if ((tmp & PHASE_MASK) != p) {
F
Finn Thain 已提交
1673
			dprintk(NDEBUG_PIO, "scsi%d: phase mismatch\n", HOSTNO);
1674
			NCR5380_dprint_phase(NDEBUG_PIO, instance);
1675 1676
			break;
		}
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1678 1679 1680 1681 1682
		/* 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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1684
		++d;
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1685

1686 1687 1688 1689 1690 1691
		/*
		 * 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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1693 1694 1695
		if (!(p & SR_IO)) {
			if (!((p & SR_MSG) && c > 1)) {
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1696
				NCR5380_dprint(NDEBUG_PIO, instance);
1697 1698 1699 1700 1701
				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);
1702
				NCR5380_dprint(NDEBUG_PIO, instance);
1703 1704 1705 1706
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
					      ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
			}
		} else {
1707
			NCR5380_dprint(NDEBUG_PIO, instance);
1708 1709
			NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
		}
L
Linus Torvalds 已提交
1710

1711 1712 1713
		while (NCR5380_read(STATUS_REG) & SR_REQ)
			;

F
Finn Thain 已提交
1714
		dprintk(NDEBUG_HANDSHAKE, "scsi%d: req false, handshake complete\n", HOSTNO);
1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734

		/*
		 * 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);

F
Finn Thain 已提交
1735
	dprintk(NDEBUG_PIO, "scsi%d: residual %d\n", HOSTNO, c);
1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752

	*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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1753 1754 1755 1756
}

/*
 * Function : do_abort (Scsi_Host *host)
1757 1758 1759 1760
 *
 * Purpose : abort the currently established nexus.  Should only be
 *	called from a routine which can drop into a
 *
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1761 1762 1763
 * Returns : 0 on success, -1 on failure.
 */

1764
static int do_abort(struct Scsi_Host *host)
L
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1765
{
1766 1767 1768 1769
	unsigned char tmp, *msgptr, phase;
	int len;

	/* Request message out phase */
L
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1770
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781

	/*
	 * 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.
	 */

1782
	while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806
		;

	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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1807 1808 1809
}

#if defined(REAL_DMA)
1810 1811
/*
 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
L
Linus Torvalds 已提交
1812 1813 1814 1815 1816
 *      unsigned char *phase, int *count, unsigned char **data)
 *
 * Purpose : transfers data in given phase using either real
 *	or pseudo DMA.
 *
1817 1818
 * Inputs : instance - instance of driver, *phase - pointer to
 *	what phase is expected, *count - pointer to number of
L
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1819
 *	bytes to transfer, **data - pointer to data pointer.
1820
 *
L
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1821
 * Returns : -1 when different phase is entered without transferring
L
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1822
 *	maximum number of bytes, 0 if all bytes or transferred or exit
L
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1823 1824
 *	is in same phase.
 *
1825
 *	Also, *phase, *count, *data are modified in place.
L
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1826 1827 1828 1829
 *
 */


1830 1831 1832
static int NCR5380_transfer_dma(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
L
Linus Torvalds 已提交
1833
{
1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844
	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;
	}
L
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1845

1846 1847
	if (atari_read_overruns && (p & SR_IO))
		c -= atari_read_overruns;
L
Linus Torvalds 已提交
1848

F
Finn Thain 已提交
1849
	dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1850 1851
		   HOSTNO, (p & SR_IO) ? "reading" : "writing",
		   c, (p & SR_IO) ? "to" : "from", d);
L
Linus Torvalds 已提交
1852

1853
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
L
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1854 1855

#ifdef REAL_DMA
1856
	NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
L
Linus Torvalds 已提交
1857 1858
#endif /* def REAL_DMA  */

1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887
	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;
L
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1888 1889 1890 1891 1892 1893
}
#endif /* defined(REAL_DMA) */

/*
 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
 *
1894 1895
 * Purpose : run through the various SCSI phases and do as the target
 *	directs us to.  Operates on the currently connected command,
L
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1896 1897 1898 1899
 *	instance->connected.
 *
 * Inputs : instance, instance for which we are doing commands
 *
1900
 * Side effects : SCSI things happen, the disconnected queue will be
L
Linus Torvalds 已提交
1901 1902 1903
 *	modified if a command disconnects, *instance->connected will
 *	change.
 *
1904 1905
 * XXX Note : we need to watch for bus free or a reset condition here
 *	to recover from an unexpected bus free condition.
L
Linus Torvalds 已提交
1906
 */
1907 1908

static void NCR5380_information_transfer(struct Scsi_Host *instance)
L
Linus Torvalds 已提交
1909
{
1910 1911 1912 1913 1914
	SETUP_HOSTDATA(instance);
	unsigned long flags;
	unsigned char msgout = NOP;
	int sink = 0;
	int len;
L
Linus Torvalds 已提交
1915
#if defined(REAL_DMA)
1916
	int transfersize;
L
Linus Torvalds 已提交
1917
#endif
1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928
	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;
1929
				NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
1930
			}
L
Linus Torvalds 已提交
1931

1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946
			if (sink && (phase != PHASE_MSGOUT)) {
				NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
					      ICR_ASSERT_ACK);
				while (NCR5380_read(STATUS_REG) & SR_REQ)
					;
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
					      ICR_ASSERT_ATN);
				sink = 0;
				continue;
			}

			switch (phase) {
			case PHASE_DATAOUT:
L
Linus Torvalds 已提交
1947
#if (NDEBUG & NDEBUG_NO_DATAOUT)
1948 1949 1950 1951 1952
				printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
				       "aborted\n", HOSTNO);
				sink = 1;
				do_abort(instance);
				cmd->result = DID_ERROR << 16;
1953
				cmd->scsi_done(cmd);
1954
				return;
L
Linus Torvalds 已提交
1955
#endif
1956 1957 1958 1959 1960 1961 1962 1963 1964 1965
			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
1966
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
1967 1968 1969 1970
					/* ++roman: Try to merge some scatter-buffers if
					 * they are at contiguous physical addresses.
					 */
					merge_contiguous_buffers(cmd);
F
Finn Thain 已提交
1971
					dprintk(NDEBUG_INFORMATION, "scsi%d: %d bytes and %d buffers left\n",
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989
						   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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#if defined(REAL_DMA)
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002
				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 "
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							   "lun %llu to slow handshake\n", HOSTNO,
2004 2005 2006 2007 2008 2009 2010
							   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;
2011
						cmd->scsi_done(cmd);
2012 2013
						/* XXX - need to source or sink data here, as appropriate */
					} else {
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#ifdef REAL_DMA
2015 2016 2017 2018 2019 2020 2021 2022
						/* ++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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#endif
2024 2025
					}
				} else
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#endif /* defined(REAL_DMA) */
2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048
					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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#ifdef LINKED
2050 2051 2052 2053 2054
				case LINKED_CMD_COMPLETE:
				case LINKED_FLG_CMD_COMPLETE:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

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					dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked command "
2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066
						   "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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						 printk(KERN_NOTICE "scsi%d: target %d lun %llu "
2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079
							"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 "
2081 2082 2083 2084 2085
						   "done, calling scsi_done().\n",
						   HOSTNO, cmd->device->id, cmd->device->lun);
					cmd->scsi_done(cmd);
					cmd = hostdata->connected;
					break;
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#endif /* def LINKED */
2087 2088 2089 2090 2091 2092 2093
				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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					dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d, lun %llu "
2095
						  "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
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#ifdef SUPPORT_TAGS
2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107
					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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						dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu returned "
2109 2110 2111 2112 2113 2114
							   "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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#else
2116
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
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#endif
2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140
					/* 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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2142 2143 2144 2145 2146 2147
					if ((cmd->cmnd[0] == REQUEST_SENSE) &&
						hostdata->ses.cmd_len) {
						scsi_eh_restore_cmnd(cmd, &hostdata->ses);
						hostdata->ses.cmd_len = 0 ;
					}

2148 2149
					if ((cmd->cmnd[0] != REQUEST_SENSE) &&
					    (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2150 2151
						scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);

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						dprintk(NDEBUG_AUTOSENSE, "scsi%d: performing request sense\n", HOSTNO);
2153 2154 2155

						local_irq_save(flags);
						LIST(cmd,hostdata->issue_queue);
2156
						SET_NEXT(cmd, hostdata->issue_queue);
2157 2158
						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 "
2160
							  "issue queue\n", H_NO(cmd));
2161
					} else {
2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199
						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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						dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu rejected "
2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212
							   "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);
2213
					SET_NEXT(cmd, hostdata->disconnected_queue);
2214 2215 2216
					hostdata->connected = NULL;
					hostdata->disconnected_queue = cmd;
					local_irq_restore(flags);
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					dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d lun %llu was "
2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 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 2266
						  "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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					dprintk(NDEBUG_EXTENDED, "scsi%d: receiving extended message\n", HOSTNO);
2268 2269 2270 2271 2272

					len = 2;
					data = extended_msg + 1;
					phase = PHASE_MSGIN;
					NCR5380_transfer_pio(instance, &phase, &len, &data);
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					dprintk(NDEBUG_EXTENDED, "scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284
						   (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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						dprintk(NDEBUG_EXTENDED, "scsi%d: message received, residual %d\n",
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
							   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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						       "message %02x from target %d, lun %llu\n",
2319 2320 2321 2322
						       HOSTNO, tmp, cmd->device->id, cmd->device->lun);
					else
						printk(KERN_DEBUG "scsi%d: rejecting unknown "
						       "extended message "
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						       "code %02x, length %d from target %d, lun %llu\n",
2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338
						       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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#ifdef SUPPORT_TAGS
2340
					cmd_free_tag(cmd);
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2341
#else
2342
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
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2343
#endif
2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370
					hostdata->connected = NULL;
					cmd->result = DID_ERROR << 16;
					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);
2371
				NCR5380_dprint(NDEBUG_ANY, instance);
2372 2373 2374
			} /* switch(phase) */
		} /* if (tmp * SR_REQ) */
	} /* while (1) */
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}

/*
 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
 *
2380 2381
 * 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
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 *	nexus has been reestablished,
2383
 *
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 * Inputs : instance - this instance of the NCR5380.
 *
 */


2389
static void NCR5380_reselect(struct Scsi_Host *instance)
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{
2391 2392 2393 2394
	SETUP_HOSTDATA(instance);
	unsigned char target_mask;
	unsigned char lun, phase;
	int len;
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#ifdef SUPPORT_TAGS
2396
	unsigned char tag;
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2397
#endif
2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412
	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);

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	dprintk(NDEBUG_RESELECTION, "scsi%d: reselect\n", HOSTNO);
2414 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 2440 2441 2442 2443 2444 2445 2446 2447 2448

	/*
	 * 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);
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#ifdef SUPPORT_TAGS
2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463
	/* 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];
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		dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at "
2465 2466
			   "reselection\n", HOSTNO, target_mask, lun, tag);
	}
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#endif
2468 2469 2470 2471 2472 2473 2474 2475 2476

	/*
	 * 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)
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#ifdef SUPPORT_TAGS
2478
		    && (tag == tmp->tag)
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#endif
2480 2481 2482 2483 2484
		    ) {
			/* ++guenther: prevent race with falcon_release_lock */
			falcon_dont_release++;
			if (prev) {
				REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2485
				SET_NEXT(prev, NEXT(tmp));
2486 2487 2488 2489
			} else {
				REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
				hostdata->disconnected_queue = NEXT(tmp);
			}
2490
			SET_NEXT(tmp, NULL);
2491 2492
			break;
		}
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	}
2494 2495 2496

	if (!tmp) {
		printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
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2497
#ifdef SUPPORT_TAGS
2498
		       "tag %d "
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2499
#endif
2500 2501
		       "not in disconnected_queue.\n",
		       HOSTNO, target_mask, lun
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2502
#ifdef SUPPORT_TAGS
2503
		       , tag
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2504
#endif
2505 2506 2507 2508 2509 2510 2511 2512
			);
		/*
		 * Since we have an established nexus that we can't do anything
		 * with, we must abort it.
		 */
		do_abort(instance);
		return;
	}
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2513

2514 2515
	/* Accept message by clearing ACK */
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
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2516

2517
	hostdata->connected = tmp;
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2518
	dprintk(NDEBUG_RESELECTION, "scsi%d: nexus established, target = %d, lun = %llu, tag = %d\n",
2519 2520
		   HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
	falcon_dont_release--;
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2521 2522 2523 2524 2525 2526 2527 2528
}


/*
 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
 *
 * Purpose : abort a command
 *
2529 2530
 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
 *	host byte of the result field to, if zero DID_ABORTED is
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2531 2532
 *	used.
 *
2533
 * Returns : SUCCESS - success, FAILED on failure.
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2534
 *
2535 2536
 * XXX - there is no way to abort the command that is currently
 *	 connected, you have to wait for it to complete.  If this is
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2537
 *	 a problem, we could implement longjmp() / setjmp(), setjmp()
2538
 *	 called where the loop started in NCR5380_main().
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2539 2540 2541
 */

static
2542
int NCR5380_abort(Scsi_Cmnd *cmd)
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2543
{
2544 2545 2546 2547
	struct Scsi_Host *instance = cmd->device->host;
	SETUP_HOSTDATA(instance);
	Scsi_Cmnd *tmp, **prev;
	unsigned long flags;
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2548

2549
	scmd_printk(KERN_NOTICE, cmd, "aborting command\n");
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2550

2551 2552 2553
	NCR5380_print_status(instance);

	local_irq_save(flags);
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2554

2555 2556 2557
	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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2558

F
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2559
	dprintk(NDEBUG_ABORT, "scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2560 2561
		    NCR5380_read(BUS_AND_STATUS_REG),
		    NCR5380_read(STATUS_REG));
L
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2562 2563

#if 1
2564 2565 2566 2567 2568
	/*
	 * 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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2569

2570
	if (hostdata->connected == cmd) {
L
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2571

F
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2572
		dprintk(NDEBUG_ABORT, "scsi%d: aborting connected command\n", HOSTNO);
2573 2574 2575 2576
		/*
		 * We should perform BSY checking, and make sure we haven't slipped
		 * into BUS FREE.
		 */
L
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2577

2578 2579 2580 2581 2582 2583
		/*	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
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2584

2585 2586 2587 2588
		/*
		 * Return control to the executing NCR drive so we can clear the
		 * aborted flag and get back into our main loop.
		 */
L
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2589

2590 2591 2592 2593
		if (do_abort(instance) == 0) {
			hostdata->aborted = 1;
			hostdata->connected = NULL;
			cmd->result = DID_ABORT << 16;
L
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2594
#ifdef SUPPORT_TAGS
2595
			cmd_free_tag(cmd);
L
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2596
#else
2597
			hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
L
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2598
#endif
2599 2600 2601
			local_irq_restore(flags);
			cmd->scsi_done(cmd);
			falcon_release_lock_if_possible(hostdata);
2602
			return SUCCESS;
2603 2604 2605
		} else {
/*			local_irq_restore(flags); */
			printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2606
			return FAILED;
2607 2608
		}
	}
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2609 2610
#endif

2611 2612 2613 2614 2615 2616 2617 2618 2619 2620
	/*
	 * 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);
2621
			SET_NEXT(tmp, NULL);
2622 2623
			tmp->result = DID_ABORT << 16;
			local_irq_restore(flags);
F
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2624
			dprintk(NDEBUG_ABORT, "scsi%d: abort removed command from issue queue.\n",
2625 2626 2627 2628 2629
				    HOSTNO);
			/* Tagged queuing note: no tag to free here, hasn't been assigned
			 * yet... */
			tmp->scsi_done(tmp);
			falcon_release_lock_if_possible(hostdata);
2630
			return SUCCESS;
2631
		}
L
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2632 2633
	}

2634 2635 2636 2637 2638 2639 2640 2641 2642 2643
	/*
	 * 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
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2644

2645 2646
	if (hostdata->connected) {
		local_irq_restore(flags);
F
Finn Thain 已提交
2647
		dprintk(NDEBUG_ABORT, "scsi%d: abort failed, command connected.\n", HOSTNO);
2648
		return FAILED;
2649
	}
L
Linus Torvalds 已提交
2650

2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679
	/*
	 * 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
2680
			dprintk(NDEBUG_ABORT, "scsi%d: aborting disconnected command.\n", HOSTNO);
2681

2682
			if (NCR5380_select(instance, cmd))
2683
				return FAILED;
L
Linus Torvalds 已提交
2684

F
Finn Thain 已提交
2685
			dprintk(NDEBUG_ABORT, "scsi%d: nexus reestablished.\n", HOSTNO);
2686 2687 2688 2689 2690 2691 2692 2693 2694 2695

			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);
2696
					SET_NEXT(tmp, NULL);
2697 2698 2699 2700 2701
					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
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2702
#ifdef SUPPORT_TAGS
2703
					cmd_free_tag(tmp);
L
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2704
#else
2705
					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
L
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2706
#endif
2707 2708 2709
					local_irq_restore(flags);
					tmp->scsi_done(tmp);
					falcon_release_lock_if_possible(hostdata);
2710
					return SUCCESS;
2711 2712
				}
			}
L
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2713 2714 2715
		}
	}

2716 2717 2718 2719 2720 2721 2722 2723 2724
	/*
	 * 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
2725

2726
	local_irq_restore(flags);
2727
	printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO);
L
Linus Torvalds 已提交
2728

2729 2730 2731 2732 2733
	/* 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
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2734

2735
	return FAILED;
L
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2736 2737 2738
}


2739
/*
L
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2740
 * Function : int NCR5380_reset (Scsi_Cmnd *cmd)
2741
 *
L
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2742 2743
 * Purpose : reset the SCSI bus.
 *
2744
 * Returns : SUCCESS or FAILURE
L
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2745
 *
2746
 */
L
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2747

2748
static int NCR5380_bus_reset(Scsi_Cmnd *cmd)
L
Linus Torvalds 已提交
2749
{
2750 2751 2752
	SETUP_HOSTDATA(cmd->device->host);
	int i;
	unsigned long flags;
2753
#if defined(RESET_RUN_DONE)
2754
	Scsi_Cmnd *connected, *disconnected_queue;
L
Linus Torvalds 已提交
2755 2756
#endif

2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777
	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);

2778 2779 2780 2781 2782 2783 2784 2785
	/* 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 */
2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799
	/* 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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2800
#ifdef SUPPORT_TAGS
2801
	free_all_tags();
L
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2802
#endif
2803 2804
	for (i = 0; i < 8; ++i)
		hostdata->busy[i] = 0;
L
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2805
#ifdef REAL_DMA
2806
	hostdata->dma_len = 0;
L
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2807
#endif
2808
	local_irq_restore(flags);
L
Linus Torvalds 已提交
2809

2810 2811 2812 2813
	/* 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
2814

2815
	if ((cmd = connected)) {
F
Finn Thain 已提交
2816
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd));
2817 2818 2819
		cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
		cmd->scsi_done(cmd);
	}
L
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2820

2821 2822
	for (i = 0; (cmd = disconnected_queue); ++i) {
		disconnected_queue = NEXT(cmd);
2823
		SET_NEXT(cmd, NULL);
2824 2825 2826 2827
		cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
		cmd->scsi_done(cmd);
	}
	if (i > 0)
F
Finn Thain 已提交
2828
		dprintk(NDEBUG_ABORT, "scsi: reset aborted %d disconnected command(s)\n", i);
L
Linus Torvalds 已提交
2829

2830 2831 2832 2833 2834 2835
	/* 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
2836

2837 2838 2839 2840
	/* 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
	 */
2841
	return SUCCESS;
L
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2842 2843
#else /* 1 */

2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867
	/* 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
2868
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2869
	if (hostdata->connected)
F
Finn Thain 已提交
2870
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd));
2871
	if (hostdata->disconnected_queue)
F
Finn Thain 已提交
2872
		dprintk(NDEBUG_ABORT, "scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
2873 2874 2875 2876 2877

	local_irq_save(flags);
	hostdata->issue_queue = NULL;
	hostdata->connected = NULL;
	hostdata->disconnected_queue = NULL;
L
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2878
#ifdef SUPPORT_TAGS
2879
	free_all_tags();
L
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2880
#endif
2881 2882
	for (i = 0; i < 8; ++i)
		hostdata->busy[i] = 0;
L
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2883
#ifdef REAL_DMA
2884
	hostdata->dma_len = 0;
L
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2885
#endif
2886
	local_irq_restore(flags);
L
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2887

2888
	/* we did no complete reset of all commands, so a wakeup is required */
2889
	return SUCCESS;
L
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2890 2891
#endif /* 1 */
}