NCR5380.c 72.1 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
 * architecture.
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 *
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 * Note that these routines also work with NR53c400 family chips.
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 *
 * Copyright 1993, Drew Eckhardt
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 * Visionary Computing
 * (Unix and Linux consulting and custom programming)
 * drew@colorado.edu
 * +1 (303) 666-5836
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 *
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 * For more information, please consult
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 *
 * NCR 5380 Family
 * SCSI Protocol Controller
 * Databook
 *
 * NCR Microelectronics
 * 1635 Aeroplaza Drive
 * Colorado Springs, CO 80916
 * 1+ (719) 578-3400
 * 1+ (800) 334-5454
 */

/*
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 * With contributions from Ray Van Tassle, Ingmar Baumgart,
 * Ronald van Cuijlenborg, Alan Cox and others.
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 */

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/* Ported to Atari by Roman Hodek and others. */

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/* Adapted for the Sun 3 by Sam Creasey. */

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/*
 * Design
 *
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 * This is a generic 5380 driver.  To use it on a different platform,
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 * one simply writes appropriate system specific macros (ie, data
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 * transfer - some PC's will use the I/O bus, 68K's must use
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 * memory mapped) and drops this file in their 'C' wrapper.
 *
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 * As far as command queueing, two queues are maintained for
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 * each 5380 in the system - commands that haven't been issued yet,
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 * and commands that are currently executing.  This means that an
 * unlimited number of commands may be queued, letting
 * more commands propagate from the higher driver levels giving higher
 * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported,
 * allowing multiple commands to propagate all the way to a SCSI-II device
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 * while a command is already executing.
 *
 *
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 * Issues specific to the NCR5380 :
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 *
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 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
 * piece of hardware that requires you to sit in a loop polling for
 * the REQ signal as long as you are connected.  Some devices are
 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
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 * while doing long seek operations. [...] 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 from a workqueue for each NCR5380 host in the
 * system.  It attempts to establish I_T_L or I_T_L_Q nexuses by
 * removing the commands from the issue queue and calling
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 * NCR5380_select() if a nexus is not established.
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 *
 * Once a nexus is established, the NCR5380_information_transfer()
 * phase goes through the various phases as instructed by the target.
 * if the target goes into MSG IN and sends a DISCONNECT message,
 * the command structure is placed into the per instance disconnected
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 * queue, and NCR5380_main tries to find more work.  If the target is
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 * 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 :
 * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be
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 * defined.
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 *
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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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 *
 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
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 * transceivers.
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 *
 * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
 *
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 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
 *
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 * These macros MUST be defined :
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 *
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 * NCR5380_read(register)  - read from the specified register
 *
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 * NCR5380_write(register, value) - write to the specific register
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 *
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 * NCR5380_implementation_fields  - additional fields needed for this
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 * specific implementation of the NCR5380
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 *
 * Either real DMA *or* pseudo DMA may be implemented
 *
 * NCR5380_dma_write_setup(instance, src, count) - initialize
 * NCR5380_dma_read_setup(instance, dst, count) - initialize
 * NCR5380_dma_residual(instance); - residual count
 *
 * The generic driver is initialized by calling NCR5380_init(instance),
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 * after setting the appropriate host specific fields and ID.  If the
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 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
 * possible) function may be used.
 */

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#ifndef NCR5380_io_delay
#define NCR5380_io_delay(x)
#endif

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#ifndef NCR5380_acquire_dma_irq
#define NCR5380_acquire_dma_irq(x)	(1)
#endif

#ifndef NCR5380_release_dma_irq
#define NCR5380_release_dma_irq(x)
#endif

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static int do_abort(struct Scsi_Host *);
static void do_reset(struct Scsi_Host *);
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/**
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 * initialize_SCp - init the scsi pointer field
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 * @cmd: command block to set up
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 *
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 * Set up the internal fields in the SCSI command.
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 */

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static inline void initialize_SCp(struct scsi_cmnd *cmd)
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{
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	/*
	 * Initialize the Scsi Pointer field so that all of the commands in the
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	 * various queues are valid.
	 */

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	if (scsi_bufflen(cmd)) {
		cmd->SCp.buffer = scsi_sglist(cmd);
		cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
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		cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
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		cmd->SCp.this_residual = cmd->SCp.buffer->length;
	} else {
		cmd->SCp.buffer = NULL;
		cmd->SCp.buffers_residual = 0;
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		cmd->SCp.ptr = NULL;
		cmd->SCp.this_residual = 0;
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	}
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	cmd->SCp.Status = 0;
	cmd->SCp.Message = 0;
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}

/**
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 * NCR5380_poll_politely2 - wait for two chip register values
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 * @instance: controller to poll
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 * @reg1: 5380 register to poll
 * @bit1: Bitmask to check
 * @val1: Expected value
 * @reg2: Second 5380 register to poll
 * @bit2: Second bitmask to check
 * @val2: Second expected value
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 * @wait: Time-out in jiffies
 *
 * Polls the chip in a reasonably efficient manner waiting for an
 * event to occur. After a short quick poll we begin to yield the CPU
 * (if possible). In irq contexts the time-out is arbitrarily limited.
 * Callers may hold locks as long as they are held in irq mode.
 *
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 * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.
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 */
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static int NCR5380_poll_politely2(struct Scsi_Host *instance,
                                  int reg1, int bit1, int val1,
                                  int reg2, int bit2, int val2, int wait)
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{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	unsigned long deadline = jiffies + wait;
	unsigned long n;

	/* Busy-wait for up to 10 ms */
	n = min(10000U, jiffies_to_usecs(wait));
	n *= hostdata->accesses_per_ms;
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	n /= 2000;
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	do {
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		if ((NCR5380_read(reg1) & bit1) == val1)
			return 0;
		if ((NCR5380_read(reg2) & bit2) == val2)
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			return 0;
		cpu_relax();
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	} while (n--);

	if (irqs_disabled() || in_interrupt())
		return -ETIMEDOUT;

	/* Repeatedly sleep for 1 ms until deadline */
	while (time_is_after_jiffies(deadline)) {
		schedule_timeout_uninterruptible(1);
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		if ((NCR5380_read(reg1) & bit1) == val1)
			return 0;
		if ((NCR5380_read(reg2) & bit2) == val2)
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			return 0;
	}
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	return -ETIMEDOUT;
}

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static inline int NCR5380_poll_politely(struct Scsi_Host *instance,
                                        int reg, int bit, int val, int wait)
{
	return NCR5380_poll_politely2(instance, reg, bit, val,
	                                        reg, bit, val, wait);
}

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#if NDEBUG
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static struct {
	unsigned char mask;
	const char *name;
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} 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"},
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	{0, NULL}
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},
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basrs[] = {
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	{BASR_END_DMA_TRANSFER, "END OF DMA"},
	{BASR_DRQ, "DRQ"},
	{BASR_PARITY_ERROR, "PARITY ERROR"},
	{BASR_IRQ, "IRQ"},
	{BASR_PHASE_MATCH, "PHASE MATCH"},
	{BASR_BUSY_ERROR, "BUSY ERROR"},
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	{BASR_ATN, "ATN"},
	{BASR_ACK, "ACK"},
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	{0, NULL}
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},
icrs[] = {
	{ICR_ASSERT_RST, "ASSERT RST"},
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	{ICR_ARBITRATION_PROGRESS, "ARB. IN PROGRESS"},
	{ICR_ARBITRATION_LOST, "LOST ARB."},
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	{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"},
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	{0, NULL}
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},
mrs[] = {
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	{MR_BLOCK_DMA_MODE, "BLOCK DMA MODE"},
	{MR_TARGET, "TARGET"},
	{MR_ENABLE_PAR_CHECK, "PARITY CHECK"},
	{MR_ENABLE_PAR_INTR, "PARITY INTR"},
	{MR_ENABLE_EOP_INTR, "EOP INTR"},
	{MR_MONITOR_BSY, "MONITOR BSY"},
	{MR_DMA_MODE, "DMA MODE"},
	{MR_ARBITRATE, "ARBITRATE"},
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	{0, NULL}
};

/**
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 * NCR5380_print - print scsi bus signals
 * @instance: adapter state to dump
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 *
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 * Print the SCSI bus signals for debugging purposes
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 */

static void NCR5380_print(struct Scsi_Host *instance)
{
	unsigned char status, data, basr, mr, icr, i;

	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);

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	printk(KERN_DEBUG "SR =   0x%02x : ", status);
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	for (i = 0; signals[i].mask; ++i)
		if (status & signals[i].mask)
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			printk(KERN_CONT "%s, ", signals[i].name);
	printk(KERN_CONT "\nBASR = 0x%02x : ", basr);
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	for (i = 0; basrs[i].mask; ++i)
		if (basr & basrs[i].mask)
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			printk(KERN_CONT "%s, ", basrs[i].name);
	printk(KERN_CONT "\nICR =  0x%02x : ", icr);
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	for (i = 0; icrs[i].mask; ++i)
		if (icr & icrs[i].mask)
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			printk(KERN_CONT "%s, ", icrs[i].name);
	printk(KERN_CONT "\nMR =   0x%02x : ", mr);
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	for (i = 0; mrs[i].mask; ++i)
		if (mr & mrs[i].mask)
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			printk(KERN_CONT "%s, ", mrs[i].name);
	printk(KERN_CONT "\n");
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}

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static struct {
	unsigned char value;
	const char *name;
} phases[] = {
	{PHASE_DATAOUT, "DATAOUT"},
	{PHASE_DATAIN, "DATAIN"},
	{PHASE_CMDOUT, "CMDOUT"},
	{PHASE_STATIN, "STATIN"},
	{PHASE_MSGOUT, "MSGOUT"},
	{PHASE_MSGIN, "MSGIN"},
	{PHASE_UNKNOWN, "UNKNOWN"}
};
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/**
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 * NCR5380_print_phase - show SCSI phase
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 * @instance: adapter to dump
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 *
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 * Print the current SCSI phase for debugging purposes
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 */

static void NCR5380_print_phase(struct Scsi_Host *instance)
{
	unsigned char status;
	int i;

	status = NCR5380_read(STATUS_REG);
	if (!(status & SR_REQ))
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		shost_printk(KERN_DEBUG, instance, "REQ not asserted, phase unknown.\n");
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	else {
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		for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
		     (phases[i].value != (status & PHASE_MASK)); ++i)
			;
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		shost_printk(KERN_DEBUG, instance, "phase %s\n", phases[i].name);
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	}
}
#endif


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static int probe_irq __initdata;
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/**
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 * probe_intr	-	helper for IRQ autoprobe
 * @irq: interrupt number
 * @dev_id: unused
 * @regs: unused
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 *
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 * Set a flag to indicate the IRQ in question was received. This is
 * used by the IRQ probe code.
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 */
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static irqreturn_t __init probe_intr(int irq, void *dev_id)
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{
	probe_irq = irq;
	return IRQ_HANDLED;
}

/**
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 * NCR5380_probe_irq	-	find the IRQ of an NCR5380
 * @instance: NCR5380 controller
 * @possible: bitmask of ISA IRQ lines
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 *
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 * Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ
 * and then looking to see what interrupt actually turned up.
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 */

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static int __init __maybe_unused NCR5380_probe_irq(struct Scsi_Host *instance,
						int possible)
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{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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	unsigned long timeout;
	int trying_irqs, i, mask;

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	for (trying_irqs = 0, i = 1, mask = 2; i < 16; ++i, mask <<= 1)
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		if ((mask & possible) && (request_irq(i, &probe_intr, 0, "NCR-probe", NULL) == 0))
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			trying_irqs |= mask;

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	timeout = jiffies + msecs_to_jiffies(250);
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	probe_irq = NO_IRQ;
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	/*
	 * A interrupt is triggered whenever BSY = false, SEL = true
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	 * and a bit set in the SELECT_ENABLE_REG is asserted on the
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	 * SCSI bus.
	 *
	 * Note that the bus is only driven when the phase control signals
	 * (I/O, C/D, and MSG) match those in the TCR, so we must reset that
	 * to zero.
	 */

	NCR5380_write(TARGET_COMMAND_REG, 0);
	NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL);

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	while (probe_irq == NO_IRQ && time_before(jiffies, timeout))
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		schedule_timeout_uninterruptible(1);
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	NCR5380_write(SELECT_ENABLE_REG, 0);
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

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	for (i = 1, mask = 2; i < 16; ++i, mask <<= 1)
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		if (trying_irqs & mask)
			free_irq(i, NULL);

	return probe_irq;
}

/**
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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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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, "
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	         "flags { %s%s%s}, "
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	         "options { %s} ",
	         instance->hostt->name, instance->io_port, instance->n_io_port,
	         instance->base, instance->irq,
	         instance->can_queue, instance->cmd_per_lun,
	         instance->sg_tablesize, instance->this_id,
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	         hostdata->flags & FLAG_DMA_FIXUP     ? "DMA_FIXUP "     : "",
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	         hostdata->flags & FLAG_NO_PSEUDO_DMA ? "NO_PSEUDO_DMA " : "",
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	         hostdata->flags & FLAG_TOSHIBA_DELAY ? "TOSHIBA_DELAY "  : "",
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#ifdef DIFFERENTIAL
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	         "DIFFERENTIAL "
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#endif
#ifdef PARITY
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	         "PARITY "
#endif
	         "");
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}

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

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static int NCR5380_init(struct Scsi_Host *instance, int flags)
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{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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	int i;
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	unsigned long deadline;
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	instance->max_lun = 7;

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	hostdata->host = instance;
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	hostdata->id_mask = 1 << instance->this_id;
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	hostdata->id_higher_mask = 0;
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	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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	hostdata->dma_len = 0;

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	spin_lock_init(&hostdata->lock);
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	hostdata->connected = NULL;
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	hostdata->sensing = NULL;
	INIT_LIST_HEAD(&hostdata->autosense);
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	INIT_LIST_HEAD(&hostdata->unissued);
	INIT_LIST_HEAD(&hostdata->disconnected);

512
	hostdata->flags = flags;
513

514
	INIT_WORK(&hostdata->main_task, NCR5380_main);
515 516 517 518 519 520
	hostdata->work_q = alloc_workqueue("ncr5380_%d",
	                        WQ_UNBOUND | WQ_MEM_RECLAIM,
	                        1, instance->host_no);
	if (!hostdata->work_q)
		return -ENOMEM;

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	prepare_info(instance);

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	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);
527 528 529 530 531 532 533 534 535 536 537 538 539 540 541

	/* Calibrate register polling loop */
	i = 0;
	deadline = jiffies + 1;
	do {
		cpu_relax();
	} while (time_is_after_jiffies(deadline));
	deadline += msecs_to_jiffies(256);
	do {
		NCR5380_read(STATUS_REG);
		++i;
		cpu_relax();
	} while (time_is_after_jiffies(deadline));
	hostdata->accesses_per_ms = i / 256;

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	return 0;
}
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/**
 * NCR5380_maybe_reset_bus - Detect and correct bus wedge problems.
 * @instance: adapter to check
 *
 * If the system crashed, it may have crashed with a connected target and
 * the SCSI bus busy. Check for BUS FREE phase. If not, try to abort the
 * currently established nexus, which we know nothing about. Failing that
 * do a bus reset.
 *
 * Note that a bus reset will cause the chip to assert IRQ.
 *
 * Returns 0 if successful, otherwise -ENXIO.
 */

static int NCR5380_maybe_reset_bus(struct Scsi_Host *instance)
{
561
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
562
	int pass;
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	for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
		switch (pass) {
		case 1:
		case 3:
		case 5:
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			shost_printk(KERN_ERR, instance, "SCSI bus busy, waiting up to five seconds\n");
			NCR5380_poll_politely(instance,
			                      STATUS_REG, SR_BSY, 0, 5 * HZ);
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			break;
		case 2:
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			shost_printk(KERN_ERR, instance, "bus busy, attempting abort\n");
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			do_abort(instance);
			break;
		case 4:
578
			shost_printk(KERN_ERR, instance, "bus busy, attempting reset\n");
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			do_reset(instance);
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			/* Wait after a reset; the SCSI standard calls for
			 * 250ms, we wait 500ms to be on the safe side.
			 * But some Toshiba CD-ROMs need ten times that.
			 */
			if (hostdata->flags & FLAG_TOSHIBA_DELAY)
				msleep(2500);
			else
				msleep(500);
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			break;
		case 6:
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			shost_printk(KERN_ERR, instance, "bus locked solid\n");
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			return -ENXIO;
		}
	}
	return 0;
}

/**
598
 * NCR5380_exit - remove an NCR5380
599
 * @instance: adapter to remove
600 601
 *
 * Assumes that no more work can be queued (e.g. by NCR5380_intr).
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 */

604
static void NCR5380_exit(struct Scsi_Host *instance)
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{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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608
	cancel_work_sync(&hostdata->main_task);
609
	destroy_workqueue(hostdata->work_q);
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}

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/**
 * complete_cmd - finish processing a command and return it to the SCSI ML
 * @instance: the host instance
 * @cmd: command to complete
 */

static void complete_cmd(struct Scsi_Host *instance,
                         struct scsi_cmnd *cmd)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);

	dsprintk(NDEBUG_QUEUES, instance, "complete_cmd: cmd %p\n", cmd);

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	if (hostdata->sensing == cmd) {
		/* Autosense processing ends here */
		if ((cmd->result & 0xff) != SAM_STAT_GOOD) {
			scsi_eh_restore_cmnd(cmd, &hostdata->ses);
			set_host_byte(cmd, DID_ERROR);
		} else
			scsi_eh_restore_cmnd(cmd, &hostdata->ses);
		hostdata->sensing = NULL;
	}

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	hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);

	cmd->scsi_done(cmd);
}

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/**
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 * NCR5380_queue_command - queue a command
 * @instance: the relevant SCSI adapter
 * @cmd: SCSI command
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 *
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 * cmd is added to the per-instance issue queue, with minor
 * twiddling done to the host specific fields of cmd.  If the
 * main coroutine is not running, it is restarted.
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 */

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static int NCR5380_queue_command(struct Scsi_Host *instance,
                                 struct scsi_cmnd *cmd)
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{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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	struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);
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	unsigned long flags;
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#if (NDEBUG & NDEBUG_NO_WRITE)
	switch (cmd->cmnd[0]) {
	case WRITE_6:
	case WRITE_10:
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		shost_printk(KERN_DEBUG, instance, "WRITE attempted with NDEBUG_NO_WRITE set\n");
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		cmd->result = (DID_ERROR << 16);
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		cmd->scsi_done(cmd);
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		return 0;
	}
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#endif /* (NDEBUG & NDEBUG_NO_WRITE) */
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	cmd->result = 0;

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	if (!NCR5380_acquire_dma_irq(instance))
		return SCSI_MLQUEUE_HOST_BUSY;

673
	spin_lock_irqsave(&hostdata->lock, flags);
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	/*
	 * Insert the cmd into the issue queue. Note that REQUEST SENSE
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	 * commands are added to the head of the queue since any command will
678
	 * clear the contingent allegiance condition that exists and the
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	 * sense data is only guaranteed to be valid while the condition exists.
	 */

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	if (cmd->cmnd[0] == REQUEST_SENSE)
		list_add(&ncmd->list, &hostdata->unissued);
	else
		list_add_tail(&ncmd->list, &hostdata->unissued);

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	spin_unlock_irqrestore(&hostdata->lock, flags);
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	dsprintk(NDEBUG_QUEUES, instance, "command %p added to %s of queue\n",
	         cmd, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
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	/* Kick off command processing */
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	queue_work(hostdata->work_q, &hostdata->main_task);
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	return 0;
}

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

	/* Caller does the locking needed to set & test these data atomically */
	if (list_empty(&hostdata->disconnected) &&
	    list_empty(&hostdata->unissued) &&
	    list_empty(&hostdata->autosense) &&
	    !hostdata->connected &&
	    !hostdata->selecting)
		NCR5380_release_dma_irq(instance);
}

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/**
 * dequeue_next_cmd - dequeue a command for processing
 * @instance: the scsi host instance
 *
 * Priority is given to commands on the autosense queue. These commands
 * need autosense because of a CHECK CONDITION result.
 *
 * Returns a command pointer if a command is found for a target that is
 * not already busy. Otherwise returns NULL.
 */

static struct scsi_cmnd *dequeue_next_cmd(struct Scsi_Host *instance)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	struct NCR5380_cmd *ncmd;
	struct scsi_cmnd *cmd;

727
	if (hostdata->sensing || list_empty(&hostdata->autosense)) {
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		list_for_each_entry(ncmd, &hostdata->unissued, list) {
			cmd = NCR5380_to_scmd(ncmd);
			dsprintk(NDEBUG_QUEUES, instance, "dequeue: cmd=%p target=%d busy=0x%02x lun=%llu\n",
			         cmd, scmd_id(cmd), hostdata->busy[scmd_id(cmd)], cmd->device->lun);

			if (!(hostdata->busy[scmd_id(cmd)] & (1 << cmd->device->lun))) {
				list_del(&ncmd->list);
				dsprintk(NDEBUG_QUEUES, instance,
				         "dequeue: removed %p from issue queue\n", cmd);
				return cmd;
			}
		}
	} else {
		/* Autosense processing begins here */
		ncmd = list_first_entry(&hostdata->autosense,
		                        struct NCR5380_cmd, list);
		list_del(&ncmd->list);
		cmd = NCR5380_to_scmd(ncmd);
		dsprintk(NDEBUG_QUEUES, instance,
		         "dequeue: removed %p from autosense queue\n", cmd);
		scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
		hostdata->sensing = cmd;
		return cmd;
	}
	return NULL;
}

static void requeue_cmd(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);

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	if (hostdata->sensing == cmd) {
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		scsi_eh_restore_cmnd(cmd, &hostdata->ses);
		list_add(&ncmd->list, &hostdata->autosense);
		hostdata->sensing = NULL;
	} else
		list_add(&ncmd->list, &hostdata->unissued);
}

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/**
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 * NCR5380_main - NCR state machines
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 *
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 * NCR5380_main is a coroutine that runs as long as more work can
 * be done on the NCR5380 host adapters in a system.  Both
 * NCR5380_queue_command() and NCR5380_intr() will try to start it
 * in case it is not running.
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 */

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static void NCR5380_main(struct work_struct *work)
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{
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	struct NCR5380_hostdata *hostdata =
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		container_of(work, struct NCR5380_hostdata, main_task);
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	struct Scsi_Host *instance = hostdata->host;
	int done;
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	do {
		done = 1;
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		spin_lock_irq(&hostdata->lock);
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		while (!hostdata->connected && !hostdata->selecting) {
			struct scsi_cmnd *cmd = dequeue_next_cmd(instance);

			if (!cmd)
				break;
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			dsprintk(NDEBUG_MAIN, instance, "main: dequeued %p\n", cmd);
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			/*
			 * 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.
			 */
			/*
			 * REQUEST SENSE commands are issued without tagged
			 * queueing, even on SCSI-II devices because the
			 * contingent allegiance condition exists for the
			 * entire unit.
			 */
808

809
			if (!NCR5380_select(instance, cmd)) {
810
				dsprintk(NDEBUG_MAIN, instance, "main: select complete\n");
811
				maybe_release_dma_irq(instance);
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			} else {
				dsprintk(NDEBUG_MAIN | NDEBUG_QUEUES, instance,
				         "main: select failed, returning %p to queue\n", cmd);
				requeue_cmd(instance, cmd);
			}
		}
818
		if (hostdata->connected && !hostdata->dma_len) {
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			dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n");
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			NCR5380_information_transfer(instance);
			done = 0;
822
		}
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		spin_unlock_irq(&hostdata->lock);
		if (!done)
			cond_resched();
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	} while (!done);
}

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/*
 * NCR5380_dma_complete - finish DMA transfer
 * @instance: the scsi host instance
 *
 * Called by the interrupt handler when DMA finishes or a phase
 * mismatch occurs (which would end the DMA transfer).
 */

static void NCR5380_dma_complete(struct Scsi_Host *instance)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	int transferred;
	unsigned char **data;
	int *count;
	int saved_data = 0, overrun = 0;
	unsigned char p;

	if (hostdata->read_overruns) {
		p = hostdata->connected->SCp.phase;
		if (p & SR_IO) {
			udelay(10);
			if ((NCR5380_read(BUS_AND_STATUS_REG) &
			     (BASR_PHASE_MATCH | BASR_ACK)) ==
			    (BASR_PHASE_MATCH | BASR_ACK)) {
				saved_data = NCR5380_read(INPUT_DATA_REG);
				overrun = 1;
				dsprintk(NDEBUG_DMA, instance, "read overrun handled\n");
			}
		}
	}

860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876
#ifdef CONFIG_SUN3
	if ((sun3scsi_dma_finish(rq_data_dir(hostdata->connected->request)))) {
		pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n",
		       instance->host_no);
		BUG();
	}

	if ((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) ==
	    (BASR_PHASE_MATCH | BASR_ACK)) {
		pr_err("scsi%d: BASR %02x\n", instance->host_no,
		       NCR5380_read(BUS_AND_STATUS_REG));
		pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n",
		       instance->host_no);
		BUG();
	}
#endif

877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911
	NCR5380_write(MODE_REG, MR_BASE);
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
	NCR5380_read(RESET_PARITY_INTERRUPT_REG);

	transferred = hostdata->dma_len - NCR5380_dma_residual(instance);
	hostdata->dma_len = 0;

	data = (unsigned char **)&hostdata->connected->SCp.ptr;
	count = &hostdata->connected->SCp.this_residual;
	*data += transferred;
	*count -= transferred;

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

		if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
			cnt = toPIO = hostdata->read_overruns;
			if (overrun) {
				dsprintk(NDEBUG_DMA, instance,
				         "Got an input overrun, using saved byte\n");
				*(*data)++ = saved_data;
				(*count)--;
				cnt--;
				toPIO--;
			}
			if (toPIO > 0) {
				dsprintk(NDEBUG_DMA, instance,
				         "Doing %d byte PIO to 0x%p\n", cnt, *data);
				NCR5380_transfer_pio(instance, &p, &cnt, data);
				*count -= toPIO - cnt;
			}
		}
	}
}

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/**
913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943
 * NCR5380_intr - generic NCR5380 irq handler
 * @irq: interrupt number
 * @dev_id: device info
 *
 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
 * from the disconnected queue, and restarting NCR5380_main()
 * as required.
 *
 * The chip can assert IRQ in any of six different conditions. The IRQ flag
 * is then cleared by reading the Reset Parity/Interrupt Register (RPIR).
 * Three of these six conditions are latched in the Bus and Status Register:
 * - End of DMA (cleared by ending DMA Mode)
 * - Parity error (cleared by reading RPIR)
 * - Loss of BSY (cleared by reading RPIR)
 * Two conditions have flag bits that are not latched:
 * - Bus phase mismatch (non-maskable in DMA Mode, cleared by ending DMA Mode)
 * - Bus reset (non-maskable)
 * The remaining condition has no flag bit at all:
 * - Selection/reselection
 *
 * Hence, establishing the cause(s) of any interrupt is partly guesswork.
 * In "The DP8490 and DP5380 Comparison Guide", National Semiconductor
 * claimed that "the design of the [DP8490] interrupt logic ensures
 * interrupts will not be lost (they can be on the DP5380)."
 * The L5380/53C80 datasheet from LOGIC Devices has more details.
 *
 * Checking for bus reset by reading RST is futile because of interrupt
 * latency, but a bus reset will reset chip logic. Checking for parity error
 * is unnecessary because that interrupt is never enabled. A Loss of BSY
 * condition will clear DMA Mode. We can tell when this occurs because the
 * the Busy Monitor interrupt is enabled together with DMA Mode.
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 */

946
static irqreturn_t __maybe_unused NCR5380_intr(int irq, void *dev_id)
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{
948
	struct Scsi_Host *instance = dev_id;
949 950
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	int handled = 0;
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	unsigned char basr;
	unsigned long flags;

954
	spin_lock_irqsave(&hostdata->lock, flags);
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	basr = NCR5380_read(BUS_AND_STATUS_REG);
	if (basr & BASR_IRQ) {
		unsigned char mr = NCR5380_read(MODE_REG);
		unsigned char sr = NCR5380_read(STATUS_REG);

961 962
		dsprintk(NDEBUG_INTR, instance, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n",
		         irq, basr, sr, mr);
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		if ((mr & MR_DMA_MODE) || (mr & MR_MONITOR_BSY)) {
			/* Probably End of DMA, Phase Mismatch or Loss of BSY.
			 * We ack IRQ after clearing Mode Register. Workarounds
			 * for End of DMA errata need to happen in DMA Mode.
			 */

			dsprintk(NDEBUG_INTR, instance, "interrupt in DMA mode\n");

			if (hostdata->connected) {
				NCR5380_dma_complete(instance);
				queue_work(hostdata->work_q, &hostdata->main_task);
			} else {
				NCR5380_write(MODE_REG, MR_BASE);
				NCR5380_read(RESET_PARITY_INTERRUPT_REG);
			}
		} else if ((NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_mask) &&
980 981 982 983 984
		    (sr & (SR_SEL | SR_IO | SR_BSY | SR_RST)) == (SR_SEL | SR_IO)) {
			/* Probably reselected */
			NCR5380_write(SELECT_ENABLE_REG, 0);
			NCR5380_read(RESET_PARITY_INTERRUPT_REG);

985
			dsprintk(NDEBUG_INTR, instance, "interrupt with SEL and IO\n");
986 987 988 989

			if (!hostdata->connected) {
				NCR5380_reselect(instance);
				queue_work(hostdata->work_q, &hostdata->main_task);
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			}
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			if (!hostdata->connected)
				NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
		} else {
			/* Probably Bus Reset */
			NCR5380_read(RESET_PARITY_INTERRUPT_REG);

997
			dsprintk(NDEBUG_INTR, instance, "unknown interrupt\n");
998 999 1000
#ifdef SUN3_SCSI_VME
			dregs->csr |= CSR_DMA_ENABLE;
#endif
1001 1002 1003 1004
		}
		handled = 1;
	} else {
		shost_printk(KERN_NOTICE, instance, "interrupt without IRQ bit\n");
1005 1006 1007
#ifdef SUN3_SCSI_VME
		dregs->csr |= CSR_DMA_ENABLE;
#endif
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	}

1010
	spin_unlock_irqrestore(&hostdata->lock, flags);
1011 1012

	return IRQ_RETVAL(handled);
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}

1015
/*
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 * Function : int NCR5380_select(struct Scsi_Host *instance,
1017
 * struct scsi_cmnd *cmd)
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 *
 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1020 1021
 * including ARBITRATION, SELECTION, and initial message out for
 * IDENTIFY and queue messages.
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 *
1023
 * Inputs : instance - instantiation of the 5380 driver on which this
1024
 * target lives, cmd - SCSI command to execute.
1025
 *
1026 1027 1028
 * Returns cmd if selection failed but should be retried,
 * NULL if selection failed and should not be retried, or
 * NULL if selection succeeded (hostdata->connected == cmd).
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 *
1030
 * Side effects :
1031 1032 1033 1034
 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
 * with registers as they should have been on entry - ie
 * SELECT_ENABLE will be set appropriately, the NCR5380
 * will cease to drive any SCSI bus signals.
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 *
1036 1037 1038
 * 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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 *
1040 1041
 * If failed (no target) : cmd->scsi_done() will be called, and the
 * cmd->result host byte set to DID_BAD_TARGET.
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 */
1043

1044 1045
static struct scsi_cmnd *NCR5380_select(struct Scsi_Host *instance,
                                        struct scsi_cmnd *cmd)
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{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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	unsigned char tmp[3], phase;
	unsigned char *data;
	int len;
	int err;

	NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1054 1055
	dsprintk(NDEBUG_ARBITRATION, instance, "starting arbitration, id = %d\n",
	         instance->this_id);
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1057 1058 1059 1060 1061 1062 1063 1064 1065
	/*
	 * Arbitration and selection phases are slow and involve dropping the
	 * lock, so we have to watch out for EH. An exception handler may
	 * change 'selecting' to NULL. This function will then return NULL
	 * so that the caller will forget about 'cmd'. (During information
	 * transfer phases, EH may change 'connected' to NULL.)
	 */
	hostdata->selecting = cmd;

1066 1067
	/*
	 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
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	 * data bus during SELECTION.
	 */

	NCR5380_write(TARGET_COMMAND_REG, 0);

1073
	/*
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	 * Start arbitration.
	 */

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

1080 1081 1082
	/* The chip now waits for BUS FREE phase. Then after the 800 ns
	 * Bus Free Delay, arbitration will begin.
	 */
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1084
	spin_unlock_irq(&hostdata->lock);
1085 1086 1087
	err = NCR5380_poll_politely2(instance, MODE_REG, MR_ARBITRATE, 0,
	                INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS,
	                                       ICR_ARBITRATION_PROGRESS, HZ);
1088
	spin_lock_irq(&hostdata->lock);
1089 1090
	if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
		/* Reselection interrupt */
1091
		goto out;
1092
	}
1093 1094 1095 1096 1097
	if (!hostdata->selecting) {
		/* Command was aborted */
		NCR5380_write(MODE_REG, MR_BASE);
		goto out;
	}
1098 1099 1100 1101
	if (err < 0) {
		NCR5380_write(MODE_REG, MR_BASE);
		shost_printk(KERN_ERR, instance,
		             "select: arbitration timeout\n");
1102
		goto out;
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	}
1104
	spin_unlock_irq(&hostdata->lock);
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1105

1106
	/* The SCSI-2 arbitration delay is 2.4 us */
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	udelay(3);

	/* Check for lost arbitration */
1110 1111 1112
	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)) {
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		NCR5380_write(MODE_REG, MR_BASE);
1114
		dsprintk(NDEBUG_ARBITRATION, instance, "lost arbitration, deasserting MR_ARBITRATE\n");
1115
		spin_lock_irq(&hostdata->lock);
1116
		goto out;
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	}
1118 1119 1120 1121 1122 1123 1124

	/* 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);
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1126 1127
	/*
	 * Again, bus clear + bus settle time is 1.2us, however, this is
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	 * a minimum so we'll udelay ceil(1.2)
	 */

1131 1132 1133 1134
	if (hostdata->flags & FLAG_TOSHIBA_DELAY)
		udelay(15);
	else
		udelay(2);
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1135

1136 1137
	spin_lock_irq(&hostdata->lock);

1138 1139
	/* NCR5380_reselect() clears MODE_REG after a reselection interrupt */
	if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE))
1140 1141 1142 1143 1144 1145 1146
		goto out;

	if (!hostdata->selecting) {
		NCR5380_write(MODE_REG, MR_BASE);
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		goto out;
	}
1147

1148
	dsprintk(NDEBUG_ARBITRATION, instance, "won arbitration\n");
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1150 1151
	/*
	 * Now that we have won arbitration, start Selection process, asserting
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	 * the host and target ID's on the SCSI bus.
	 */

1155
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask | (1 << scmd_id(cmd)));
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1157
	/*
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	 * 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.
	 */

1163 1164
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY |
	              ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL);
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	NCR5380_write(MODE_REG, MR_BASE);

1167
	/*
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	 * Reselect interrupts must be turned off prior to the dropping of BSY,
	 * otherwise we will trigger an interrupt.
	 */
	NCR5380_write(SELECT_ENABLE_REG, 0);

1173 1174
	spin_unlock_irq(&hostdata->lock);

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	/*
1176
	 * The initiator shall then wait at least two deskew delays and release
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1177 1178
	 * the BSY signal.
	 */
1179
	udelay(1);        /* wingel -- wait two bus deskew delay >2*45ns */
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	/* Reset BSY */
1182 1183
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA |
	              ICR_ASSERT_ATN | ICR_ASSERT_SEL);
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1185
	/*
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	 * Something weird happens when we cease to drive BSY - looks
1187
	 * like the board/chip is letting us do another read before the
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	 * 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
1193 1194 1195
	 * 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
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	 * work there.
	 *
	 * wingel suggests that this could be due to failing to wait
	 * one deskew delay.
	 */

	udelay(1);

1204
	dsprintk(NDEBUG_SELECTION, instance, "selecting target %d\n", scmd_id(cmd));
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1206 1207
	/*
	 * The SCSI specification calls for a 250 ms timeout for the actual
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	 * selection.
	 */

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	err = NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, SR_BSY,
	                            msecs_to_jiffies(250));
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1213 1214

	if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1215
		spin_lock_irq(&hostdata->lock);
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		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		NCR5380_reselect(instance);
1218 1219
		if (!hostdata->connected)
			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1220
		shost_printk(KERN_ERR, instance, "reselection after won arbitration?\n");
1221
		goto out;
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1222
	}
F
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1223 1224

	if (err < 0) {
1225
		spin_lock_irq(&hostdata->lock);
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1226 1227
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1228 1229 1230 1231 1232 1233 1234 1235
		/* Can't touch cmd if it has been reclaimed by the scsi ML */
		if (hostdata->selecting) {
			cmd->result = DID_BAD_TARGET << 16;
			complete_cmd(instance, cmd);
			dsprintk(NDEBUG_SELECTION, instance, "target did not respond within 250ms\n");
			cmd = NULL;
		}
		goto out;
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1236 1237
	}

1238 1239 1240
	/*
	 * No less than two deskew delays after the initiator detects the
	 * BSY signal is true, it shall release the SEL signal and may
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	 * change the DATA BUS.                                     -wingel
	 */

	udelay(1);

	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);

	/*
1249
	 * Since we followed the SCSI spec, and raised ATN while SEL
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	 * 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.
	 */

	/* Wait for start of REQ/ACK handshake */

	err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
1258
	spin_lock_irq(&hostdata->lock);
1259
	if (err < 0) {
1260 1261
		shost_printk(KERN_ERR, instance, "select: REQ timeout\n");
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
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		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1263 1264 1265 1266 1267
		goto out;
	}
	if (!hostdata->selecting) {
		do_abort(instance);
		goto out;
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	}

1270 1271
	dsprintk(NDEBUG_SELECTION, instance, "target %d selected, going into MESSAGE OUT phase.\n",
	         scmd_id(cmd));
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	tmp[0] = IDENTIFY(((instance->irq == NO_IRQ) ? 0 : 1), cmd->device->lun);
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	len = 1;
	data = tmp;
	phase = PHASE_MSGOUT;
	NCR5380_transfer_pio(instance, &phase, &len, &data);
1278
	dsprintk(NDEBUG_SELECTION, instance, "nexus established.\n");
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	/* XXX need to handle errors here */
1280

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1281
	hostdata->connected = cmd;
1282
	hostdata->busy[cmd->device->id] |= 1 << cmd->device->lun;
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1283

1284 1285 1286 1287
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif

1288
	initialize_SCp(cmd);
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1290 1291 1292 1293 1294 1295 1296
	cmd = NULL;

out:
	if (!hostdata->selecting)
		return NULL;
	hostdata->selecting = NULL;
	return cmd;
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}

1299 1300
/*
 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1301
 * unsigned char *phase, int *count, unsigned char **data)
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 *
 * Purpose : transfers data in given phase using polled I/O
 *
1305
 * Inputs : instance - instance of driver, *phase - pointer to
1306 1307
 * what phase is expected, *count - pointer to number of
 * bytes to transfer, **data - pointer to data pointer.
1308
 *
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 * Returns : -1 when different phase is entered without transferring
1310
 * maximum number of bytes, 0 if all bytes are transferred or exit
1311
 * is in same phase.
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1312
 *
1313
 * Also, *phase, *count, *data are modified in place.
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 *
 * XXX Note : handling for bus free may be useful.
 */

/*
1319
 * Note : this code is not as quick as it could be, however it
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 * IS 100% reliable, and for the actual data transfer where speed
 * counts, we will always do a pseudo DMA or DMA transfer.
 */

1324 1325 1326 1327
static int NCR5380_transfer_pio(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
{
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	unsigned char p = *phase, tmp;
	int c = *count;
	unsigned char *d = *data;

1332 1333
	/*
	 * The NCR5380 chip will only drive the SCSI bus when the
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	 * phase specified in the appropriate bits of the TARGET COMMAND
	 * REGISTER match the STATUS REGISTER
	 */

1338
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
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1339 1340

	do {
1341 1342 1343
		/*
		 * Wait for assertion of REQ, after which the phase bits will be
		 * valid
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1344 1345
		 */

1346
		if (NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ) < 0)
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1347 1348
			break;

1349
		dsprintk(NDEBUG_HANDSHAKE, instance, "REQ asserted\n");
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1350 1351

		/* Check for phase mismatch */
1352
		if ((NCR5380_read(STATUS_REG) & PHASE_MASK) != p) {
1353 1354
			dsprintk(NDEBUG_PIO, instance, "phase mismatch\n");
			NCR5380_dprint_phase(NDEBUG_PIO, instance);
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1355 1356
			break;
		}
1357

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1358 1359 1360 1361 1362 1363 1364 1365
		/* Do actual transfer from SCSI bus to / from memory */
		if (!(p & SR_IO))
			NCR5380_write(OUTPUT_DATA_REG, *d);
		else
			*d = NCR5380_read(CURRENT_SCSI_DATA_REG);

		++d;

1366
		/*
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1367 1368 1369 1370 1371 1372 1373 1374 1375 1376
		 * The SCSI standard suggests that in MSGOUT phase, the initiator
		 * should drop ATN on the last byte of the message phase
		 * after REQ has been asserted for the handshake but before
		 * the initiator raises ACK.
		 */

		if (!(p & SR_IO)) {
			if (!((p & SR_MSG) && c > 1)) {
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
				NCR5380_dprint(NDEBUG_PIO, instance);
1377 1378
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ACK);
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1379
			} else {
1380 1381
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ATN);
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				NCR5380_dprint(NDEBUG_PIO, instance);
1383 1384
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
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1385 1386 1387 1388 1389 1390
			}
		} else {
			NCR5380_dprint(NDEBUG_PIO, instance);
			NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
		}

1391 1392 1393 1394
		if (NCR5380_poll_politely(instance,
		                          STATUS_REG, SR_REQ, 0, 5 * HZ) < 0)
			break;

1395
		dsprintk(NDEBUG_HANDSHAKE, instance, "REQ negated, handshake complete\n");
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1396 1397

/*
1398 1399
 * 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
1400
 * message.  ATN must be dropped as ACK is dropped.
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1401
 *
1402
 * 2.  We are in a MSGIN phase, and we are on the last byte of the
1403 1404
 * message.  We must exit with ACK asserted, so that the calling
 * code may raise ATN before dropping ACK to reject the message.
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1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415
 *
 * 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);

1416
	dsprintk(NDEBUG_PIO, instance, "residual %d\n", c);
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1417 1418 1419 1420

	*count = c;
	*data = d;
	tmp = NCR5380_read(STATUS_REG);
1421 1422 1423 1424 1425
	/* The phase read from the bus is valid if either REQ is (already)
	 * asserted or if ACK hasn't been released yet. The latter applies if
	 * we're in MSG IN, DATA IN or STATUS and all bytes have been received.
	 */
	if ((tmp & SR_REQ) || ((tmp & SR_IO) && c == 0))
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1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436
		*phase = tmp & PHASE_MASK;
	else
		*phase = PHASE_UNKNOWN;

	if (!c || (*phase == p))
		return 0;
	else
		return -1;
}

/**
1437 1438
 * do_reset - issue a reset command
 * @instance: adapter to reset
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1439
 *
1440 1441
 * Issue a reset sequence to the NCR5380 and try and get the bus
 * back into sane shape.
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1442
 *
1443 1444 1445
 * This clears the reset interrupt flag because there may be no handler for
 * it. When the driver is initialized, the NCR5380_intr() handler has not yet
 * been installed. And when in EH we may have released the ST DMA interrupt.
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1446
 */
1447

1448 1449
static void do_reset(struct Scsi_Host *instance)
{
1450 1451 1452 1453 1454
	unsigned long flags;

	local_irq_save(flags);
	NCR5380_write(TARGET_COMMAND_REG,
	              PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
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	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
1456
	udelay(50);
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	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1458 1459
	(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
	local_irq_restore(flags);
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1460 1461
}

1462 1463 1464 1465
/**
 * do_abort - abort the currently established nexus by going to
 * MESSAGE OUT phase and sending an ABORT message.
 * @instance: relevant scsi host instance
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1466
 *
1467
 * Returns 0 on success, -1 on failure.
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1468 1469
 */

1470 1471
static int do_abort(struct Scsi_Host *instance)
{
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	unsigned char *msgptr, phase, tmp;
	int len;
	int rc;

	/* Request message out phase */
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);

1479 1480 1481 1482
	/*
	 * 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
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1483
	 * other phase and will have to source/sink data.
1484
	 *
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1485 1486 1487 1488
	 * We really don't care what value was on the bus or what value
	 * the target sees, so we just handshake.
	 */

1489
	rc = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 10 * HZ);
1490
	if (rc < 0)
1491
		goto timeout;
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1492

1493
	tmp = NCR5380_read(STATUS_REG) & PHASE_MASK;
1494

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1495 1496
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

1497
	if (tmp != PHASE_MSGOUT) {
1498 1499
		NCR5380_write(INITIATOR_COMMAND_REG,
		              ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1500
		rc = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 3 * HZ);
1501
		if (rc < 0)
1502 1503
			goto timeout;
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
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	}
1505

L
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1506 1507 1508 1509
	tmp = ABORT;
	msgptr = &tmp;
	len = 1;
	phase = PHASE_MSGOUT;
1510
	NCR5380_transfer_pio(instance, &phase, &len, &msgptr);
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1511 1512 1513 1514 1515 1516 1517

	/*
	 * If we got here, and the command completed successfully,
	 * we're about to go into bus free state.
	 */

	return len ? -1 : 0;
1518 1519 1520 1521

timeout:
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
	return -1;
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1522 1523
}

1524 1525
/*
 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1526
 * unsigned char *phase, int *count, unsigned char **data)
L
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1527 1528
 *
 * Purpose : transfers data in given phase using either real
1529
 * or pseudo DMA.
L
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1530
 *
1531
 * Inputs : instance - instance of driver, *phase - pointer to
1532 1533
 * what phase is expected, *count - pointer to number of
 * bytes to transfer, **data - pointer to data pointer.
1534
 *
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1535
 * Returns : -1 when different phase is entered without transferring
1536 1537
 * maximum number of bytes, 0 if all bytes or transferred or exit
 * is in same phase.
L
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1538
 *
1539
 * Also, *phase, *count, *data are modified in place.
L
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1540 1541 1542
 */


1543 1544 1545 1546 1547
static int NCR5380_transfer_dma(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
1548 1549 1550
	int c = *count;
	unsigned char p = *phase;
	unsigned char *d = *data;
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1551
	unsigned char tmp;
1552
	int result = 0;
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1553 1554 1555 1556 1557 1558

	if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
		*phase = tmp;
		return -1;
	}

1559
	hostdata->connected->SCp.phase = p;
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1560

1561 1562 1563 1564 1565 1566
	if (p & SR_IO) {
		if (hostdata->read_overruns)
			c -= hostdata->read_overruns;
		else if (hostdata->flags & FLAG_DMA_FIXUP)
			--c;
	}
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1567

1568 1569
	dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n",
	         (p & SR_IO) ? "receive" : "send", c, d);
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1571 1572 1573 1574 1575
#ifdef CONFIG_SUN3
	/* send start chain */
	sun3scsi_dma_start(c, *data);
#endif

1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
	NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_MONITOR_BSY |
	                        MR_ENABLE_EOP_INTR);

	if (!(hostdata->flags & FLAG_LATE_DMA_SETUP)) {
		/* On the Medusa, it is a must to initialize the DMA before
		 * starting the NCR. This is also the cleaner way for the TT.
		 */
		if (p & SR_IO)
			result = NCR5380_dma_recv_setup(instance, d, c);
		else
			result = NCR5380_dma_send_setup(instance, d, c);
	}
L
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1589

1590
	/*
1591 1592
	 * On the PAS16 at least I/O recovery delays are not needed here.
	 * Everyone else seems to want them.
L
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1593 1594 1595
	 */

	if (p & SR_IO) {
1596
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1597
		NCR5380_io_delay(1);
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1598 1599
		NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
	} else {
1600
		NCR5380_io_delay(1);
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1601
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1602
		NCR5380_io_delay(1);
L
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1603
		NCR5380_write(START_DMA_SEND_REG, 0);
1604
		NCR5380_io_delay(1);
L
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1605 1606
	}

1607 1608 1609 1610 1611 1612 1613
#ifdef CONFIG_SUN3
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_DMA_ENABLE;
#endif
	sun3_dma_active = 1;
#endif

1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636
	if (hostdata->flags & FLAG_LATE_DMA_SETUP) {
		/* On the Falcon, the DMA setup must be done after the last
		 * NCR access, else the DMA setup gets trashed!
		 */
		if (p & SR_IO)
			result = NCR5380_dma_recv_setup(instance, d, c);
		else
			result = NCR5380_dma_send_setup(instance, d, c);
	}

	/* On failure, NCR5380_dma_xxxx_setup() returns a negative int. */
	if (result < 0)
		return result;

	/* For real DMA, result is the byte count. DMA interrupt is expected. */
	if (result > 0) {
		hostdata->dma_len = result;
		return 0;
	}

	/* The result is zero iff pseudo DMA send/receive was completed. */
	hostdata->dma_len = c;

L
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1637
/*
1638
 * A note regarding the DMA errata workarounds for early NMOS silicon.
F
Finn Thain 已提交
1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664
 *
 * For DMA sends, we want to wait until the last byte has been
 * transferred out over the bus before we turn off DMA mode.  Alas, there
 * seems to be no terribly good way of doing this on a 5380 under all
 * conditions.  For non-scatter-gather operations, we can wait until REQ
 * and ACK both go false, or until a phase mismatch occurs.  Gather-sends
 * are nastier, since the device will be expecting more data than we
 * are prepared to send it, and REQ will remain asserted.  On a 53C8[01] we
 * could test Last Byte Sent to assure transfer (I imagine this is precisely
 * why this signal was added to the newer chips) but on the older 538[01]
 * this signal does not exist.  The workaround for this lack is a watchdog;
 * we bail out of the wait-loop after a modest amount of wait-time if
 * the usual exit conditions are not met.  Not a terribly clean or
 * correct solution :-%
 *
 * DMA receive is equally tricky due to a nasty characteristic of the NCR5380.
 * If the chip is in DMA receive mode, it will respond to a target's
 * REQ by latching the SCSI data into the INPUT DATA register and asserting
 * ACK, even if it has _already_ been notified by the DMA controller that
 * the current DMA transfer has completed!  If the NCR5380 is then taken
 * out of DMA mode, this already-acknowledged byte is lost. This is
 * not a problem for "one DMA transfer per READ command", because
 * the situation will never arise... either all of the data is DMA'ed
 * properly, or the target switches to MESSAGE IN phase to signal a
 * disconnection (either operation bringing the DMA to a clean halt).
 * However, in order to handle scatter-receive, we must work around the
1665
 * problem.  The chosen fix is to DMA fewer bytes, then check for the
F
Finn Thain 已提交
1666 1667 1668
 * condition before taking the NCR5380 out of DMA mode.  One or two extra
 * bytes are transferred via PIO as necessary to fill out the original
 * request.
L
Linus Torvalds 已提交
1669 1670
 */

1671 1672
	if (hostdata->flags & FLAG_DMA_FIXUP) {
		if (p & SR_IO) {
L
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1673
			/*
1674
			 * The workaround was to transfer fewer bytes than we
1675
			 * intended to with the pseudo-DMA read function, wait for
L
Linus Torvalds 已提交
1676 1677
			 * the chip to latch the last byte, read it, and then disable
			 * pseudo-DMA mode.
1678
			 *
L
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1679 1680 1681 1682
			 * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
			 * REQ is deasserted when ACK is asserted, and not reasserted
			 * until ACK goes false.  Since the NCR5380 won't lower ACK
			 * until DACK is asserted, which won't happen unless we twiddle
1683 1684
			 * the DMA port or we take the NCR5380 out of DMA mode, we
			 * can guarantee that we won't handshake another extra
L
Linus Torvalds 已提交
1685 1686 1687
			 * byte.
			 */

1688 1689
			if (NCR5380_poll_politely(instance, BUS_AND_STATUS_REG,
			                          BASR_DRQ, BASR_DRQ, HZ) < 0) {
1690
				result = -1;
1691 1692 1693 1694
				shost_printk(KERN_ERR, instance, "PDMA read: DRQ timeout\n");
			}
			if (NCR5380_poll_politely(instance, STATUS_REG,
			                          SR_REQ, 0, HZ) < 0) {
1695
				result = -1;
1696
				shost_printk(KERN_ERR, instance, "PDMA read: !REQ timeout\n");
L
Linus Torvalds 已提交
1697
			}
1698 1699
			d[*count - 1] = NCR5380_read(INPUT_DATA_REG);
		} else {
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1700
			/*
1701 1702
			 * Wait for the last byte to be sent.  If REQ is being asserted for
			 * the byte we're interested, we'll ACK it and it will go false.
L
Linus Torvalds 已提交
1703
			 */
1704 1705 1706
			if (NCR5380_poll_politely2(instance,
			     BUS_AND_STATUS_REG, BASR_DRQ, BASR_DRQ,
			     BUS_AND_STATUS_REG, BASR_PHASE_MATCH, 0, HZ) < 0) {
1707
				result = -1;
1708
				shost_printk(KERN_ERR, instance, "PDMA write: DRQ and phase timeout\n");
L
Linus Torvalds 已提交
1709 1710 1711
			}
		}
	}
1712 1713

	NCR5380_dma_complete(instance);
1714
	return result;
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1715 1716 1717 1718 1719
}

/*
 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
 *
1720
 * Purpose : run through the various SCSI phases and do as the target
1721 1722
 * directs us to.  Operates on the currently connected command,
 * instance->connected.
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1723 1724 1725
 *
 * Inputs : instance, instance for which we are doing commands
 *
1726
 * Side effects : SCSI things happen, the disconnected queue will be
1727 1728
 * modified if a command disconnects, *instance->connected will
 * change.
L
Linus Torvalds 已提交
1729
 *
1730
 * XXX Note : we need to watch for bus free or a reset condition here
1731
 * to recover from an unexpected bus free condition.
L
Linus Torvalds 已提交
1732 1733
 */

1734 1735
static void NCR5380_information_transfer(struct Scsi_Host *instance)
{
F
Finn Thain 已提交
1736
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
L
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1737 1738 1739 1740 1741 1742
	unsigned char msgout = NOP;
	int sink = 0;
	int len;
	int transfersize;
	unsigned char *data;
	unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
1743
	struct scsi_cmnd *cmd;
L
Linus Torvalds 已提交
1744

1745 1746 1747 1748
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif

1749
	while ((cmd = hostdata->connected)) {
1750 1751
		struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);

L
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1752 1753 1754 1755 1756 1757 1758 1759
		tmp = NCR5380_read(STATUS_REG);
		/* We only have a valid SCSI phase when REQ is asserted */
		if (tmp & SR_REQ) {
			phase = (tmp & PHASE_MASK);
			if (phase != old_phase) {
				old_phase = phase;
				NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
			}
1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784
#ifdef CONFIG_SUN3
			if (phase == PHASE_CMDOUT) {
				void *d;
				unsigned long count;

				if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
					count = cmd->SCp.buffer->length;
					d = sg_virt(cmd->SCp.buffer);
				} else {
					count = cmd->SCp.this_residual;
					d = cmd->SCp.ptr;
				}

				if (sun3_dma_setup_done != cmd &&
				    sun3scsi_dma_xfer_len(count, cmd) > 0) {
					sun3scsi_dma_setup(instance, d, count,
					                   rq_data_dir(cmd->request));
					sun3_dma_setup_done = cmd;
				}
#ifdef SUN3_SCSI_VME
				dregs->csr |= CSR_INTR;
#endif
			}
#endif /* CONFIG_SUN3 */

L
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1785 1786 1787
			if (sink && (phase != PHASE_MSGOUT)) {
				NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

1788 1789
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
				              ICR_ASSERT_ACK);
1790 1791
				while (NCR5380_read(STATUS_REG) & SR_REQ)
					;
1792 1793
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_ATN);
L
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1794 1795 1796
				sink = 0;
				continue;
			}
1797

L
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1798 1799 1800
			switch (phase) {
			case PHASE_DATAOUT:
#if (NDEBUG & NDEBUG_NO_DATAOUT)
1801
				shost_printk(KERN_DEBUG, instance, "NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n");
L
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1802 1803 1804
				sink = 1;
				do_abort(instance);
				cmd->result = DID_ERROR << 16;
1805
				complete_cmd(instance, cmd);
F
Finn Thain 已提交
1806
				hostdata->connected = NULL;
L
Linus Torvalds 已提交
1807 1808
				return;
#endif
F
Finn Thain 已提交
1809
			case PHASE_DATAIN:
1810
				/*
L
Linus Torvalds 已提交
1811 1812 1813 1814 1815 1816 1817 1818
				 * 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
1819
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
1820 1821 1822
					dsprintk(NDEBUG_INFORMATION, instance, "%d bytes and %d buffers left\n",
					         cmd->SCp.this_residual,
					         cmd->SCp.buffers_residual);
L
Linus Torvalds 已提交
1823
				}
1824

L
Linus Torvalds 已提交
1825
				/*
1826
				 * The preferred transfer method is going to be
L
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1827 1828 1829 1830 1831 1832 1833 1834
				 * 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.
				 */

1835
				transfersize = 0;
1836
				if (!cmd->device->borken)
1837 1838
					transfersize = NCR5380_dma_xfer_len(instance, cmd, phase);

1839
				if (transfersize > 0) {
L
Linus Torvalds 已提交
1840
					len = transfersize;
1841 1842
					if (NCR5380_transfer_dma(instance, &phase,
					    &len, (unsigned char **)&cmd->SCp.ptr)) {
L
Linus Torvalds 已提交
1843
						/*
1844 1845 1846
						 * If the watchdog timer fires, all future
						 * accesses to this device will use the
						 * polled-IO.
L
Linus Torvalds 已提交
1847
						 */
J
Jeff Garzik 已提交
1848
						scmd_printk(KERN_INFO, cmd,
1849
							"switching to slow handshake\n");
L
Linus Torvalds 已提交
1850 1851 1852 1853 1854
						cmd->device->borken = 1;
						sink = 1;
						do_abort(instance);
						cmd->result = DID_ERROR << 16;
						/* XXX - need to source or sink data here, as appropriate */
1855
					}
F
Finn Thain 已提交
1856
				} else {
1857 1858 1859 1860 1861 1862 1863
					/* Break up transfer into 3 ms chunks,
					 * presuming 6 accesses per handshake.
					 */
					transfersize = min((unsigned long)cmd->SCp.this_residual,
					                   hostdata->accesses_per_ms / 2);
					len = transfersize;
					NCR5380_transfer_pio(instance, &phase, &len,
1864
					                     (unsigned char **)&cmd->SCp.ptr);
1865
					cmd->SCp.this_residual -= transfersize - len;
1866
				}
1867 1868 1869 1870
#ifdef CONFIG_SUN3
				if (sun3_dma_setup_done == cmd)
					sun3_dma_setup_done = NULL;
#endif
1871
				return;
L
Linus Torvalds 已提交
1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883
			case PHASE_MSGIN:
				len = 1;
				data = &tmp;
				NCR5380_transfer_pio(instance, &phase, &len, &data);
				cmd->SCp.Message = tmp;

				switch (tmp) {
				case ABORT:
				case COMMAND_COMPLETE:
					/* Accept message by clearing ACK */
					sink = 1;
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1884 1885 1886 1887
					dsprintk(NDEBUG_QUEUES, instance,
					         "COMMAND COMPLETE %p target %d lun %llu\n",
					         cmd, scmd_id(cmd), cmd->device->lun);

L
Linus Torvalds 已提交
1888 1889
					hostdata->connected = NULL;

F
Finn Thain 已提交
1890 1891 1892
					cmd->result &= ~0xffff;
					cmd->result |= cmd->SCp.Status;
					cmd->result |= cmd->SCp.Message << 8;
1893

F
Finn Thain 已提交
1894
					if (cmd->cmnd[0] == REQUEST_SENSE)
1895
						complete_cmd(instance, cmd);
F
Finn Thain 已提交
1896 1897 1898 1899 1900 1901 1902 1903 1904
					else {
						if (cmd->SCp.Status == SAM_STAT_CHECK_CONDITION ||
						    cmd->SCp.Status == SAM_STAT_COMMAND_TERMINATED) {
							dsprintk(NDEBUG_QUEUES, instance, "autosense: adding cmd %p to tail of autosense queue\n",
							         cmd);
							list_add_tail(&ncmd->list,
							              &hostdata->autosense);
						} else
							complete_cmd(instance, cmd);
L
Linus Torvalds 已提交
1905 1906
					}

1907 1908
					/*
					 * Restore phase bits to 0 so an interrupted selection,
L
Linus Torvalds 已提交
1909 1910 1911
					 * arbitration can resume.
					 */
					NCR5380_write(TARGET_COMMAND_REG, 0);
1912 1913 1914

					/* Enable reselect interrupts */
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1915 1916

					maybe_release_dma_irq(instance);
L
Linus Torvalds 已提交
1917 1918 1919 1920 1921 1922 1923 1924 1925
					return;
				case MESSAGE_REJECT:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
					switch (hostdata->last_message) {
					case HEAD_OF_QUEUE_TAG:
					case ORDERED_QUEUE_TAG:
					case SIMPLE_QUEUE_TAG:
						cmd->device->simple_tags = 0;
H
Hannes Reinecke 已提交
1926
						hostdata->busy[cmd->device->id] |= (1 << (cmd->device->lun & 0xFF));
L
Linus Torvalds 已提交
1927 1928 1929 1930
						break;
					default:
						break;
					}
1931
					break;
1932 1933 1934 1935 1936 1937 1938 1939
				case DISCONNECT:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
					hostdata->connected = NULL;
					list_add(&ncmd->list, &hostdata->disconnected);
					dsprintk(NDEBUG_INFORMATION | NDEBUG_QUEUES,
					         instance, "connected command %p for target %d lun %llu moved to disconnected queue\n",
					         cmd, scmd_id(cmd), cmd->device->lun);
1940

1941 1942 1943 1944 1945
					/*
					 * Restore phase bits to 0 so an interrupted selection,
					 * arbitration can resume.
					 */
					NCR5380_write(TARGET_COMMAND_REG, 0);
L
Linus Torvalds 已提交
1946

1947 1948
					/* Enable reselect interrupts */
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1949 1950 1951
#ifdef SUN3_SCSI_VME
					dregs->csr |= CSR_DMA_ENABLE;
#endif
1952
					return;
1953
					/*
L
Linus Torvalds 已提交
1954
					 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
1955
					 * operation, in violation of the SCSI spec so we can safely
L
Linus Torvalds 已提交
1956 1957
					 * ignore SAVE/RESTORE pointers calls.
					 *
1958
					 * Unfortunately, some disks violate the SCSI spec and
L
Linus Torvalds 已提交
1959
					 * don't issue the required SAVE_POINTERS message before
1960
					 * disconnecting, and we have to break spec to remain
L
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1961 1962 1963 1964 1965 1966 1967 1968
					 * compatible.
					 */
				case SAVE_POINTERS:
				case RESTORE_POINTERS:
					/* Accept message by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
					break;
				case EXTENDED_MESSAGE:
F
Finn Thain 已提交
1969 1970 1971 1972
					/*
					 * Start the message buffer with the EXTENDED_MESSAGE
					 * byte, since spi_print_msg() wants the whole thing.
					 */
L
Linus Torvalds 已提交
1973 1974 1975
					extended_msg[0] = EXTENDED_MESSAGE;
					/* Accept first byte by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1976 1977 1978

					spin_unlock_irq(&hostdata->lock);

1979
					dsprintk(NDEBUG_EXTENDED, instance, "receiving extended message\n");
L
Linus Torvalds 已提交
1980 1981 1982 1983 1984

					len = 2;
					data = extended_msg + 1;
					phase = PHASE_MSGIN;
					NCR5380_transfer_pio(instance, &phase, &len, &data);
1985 1986 1987
					dsprintk(NDEBUG_EXTENDED, instance, "length %d, code 0x%02x\n",
					         (int)extended_msg[1],
					         (int)extended_msg[2]);
L
Linus Torvalds 已提交
1988

1989 1990
					if (!len && extended_msg[1] > 0 &&
					    extended_msg[1] <= sizeof(extended_msg) - 2) {
L
Linus Torvalds 已提交
1991 1992 1993 1994 1995 1996 1997
						/* 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);
1998 1999
						dsprintk(NDEBUG_EXTENDED, instance, "message received, residual %d\n",
						         len);
L
Linus Torvalds 已提交
2000 2001 2002 2003 2004 2005 2006 2007 2008

						switch (extended_msg[2]) {
						case EXTENDED_SDTR:
						case EXTENDED_WDTR:
						case EXTENDED_MODIFY_DATA_POINTER:
						case EXTENDED_EXTENDED_IDENTIFY:
							tmp = 0;
						}
					} else if (len) {
2009
						shost_printk(KERN_ERR, instance, "error receiving extended message\n");
L
Linus Torvalds 已提交
2010 2011
						tmp = 0;
					} else {
2012 2013
						shost_printk(KERN_NOTICE, instance, "extended message code %02x length %d is too long\n",
						             extended_msg[2], extended_msg[1]);
L
Linus Torvalds 已提交
2014 2015
						tmp = 0;
					}
2016 2017 2018 2019 2020

					spin_lock_irq(&hostdata->lock);
					if (!hostdata->connected)
						return;

L
Linus Torvalds 已提交
2021 2022
					/* Fall through to reject message */

2023 2024
					/*
					 * If we get something weird that we aren't expecting,
L
Linus Torvalds 已提交
2025 2026 2027 2028
					 * reject it.
					 */
				default:
					if (!tmp) {
2029
						shost_printk(KERN_ERR, instance, "rejecting message ");
2030
						spi_print_msg(extended_msg);
L
Linus Torvalds 已提交
2031 2032
						printk("\n");
					} else if (tmp != EXTENDED_MESSAGE)
J
Jeff Garzik 已提交
2033
						scmd_printk(KERN_INFO, cmd,
2034 2035
						            "rejecting unknown message %02x\n",
						            tmp);
L
Linus Torvalds 已提交
2036
					else
J
Jeff Garzik 已提交
2037
						scmd_printk(KERN_INFO, cmd,
2038 2039
						            "rejecting unknown extended message code %02x, length %d\n",
						            extended_msg[1], extended_msg[0]);
L
Linus Torvalds 已提交
2040 2041 2042 2043

					msgout = MESSAGE_REJECT;
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
					break;
2044
				} /* switch (tmp) */
L
Linus Torvalds 已提交
2045 2046 2047 2048 2049 2050 2051 2052 2053
				break;
			case PHASE_MSGOUT:
				len = 1;
				data = &msgout;
				hostdata->last_message = msgout;
				NCR5380_transfer_pio(instance, &phase, &len, &data);
				if (msgout == ABORT) {
					hostdata->connected = NULL;
					cmd->result = DID_ERROR << 16;
2054
					complete_cmd(instance, cmd);
2055
					maybe_release_dma_irq(instance);
L
Linus Torvalds 已提交
2056 2057 2058 2059 2060 2061 2062 2063
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
					return;
				}
				msgout = NOP;
				break;
			case PHASE_CMDOUT:
				len = cmd->cmd_len;
				data = cmd->cmnd;
2064 2065 2066 2067
				/*
				 * XXX for performance reasons, on machines with a
				 * PSEUDO-DMA architecture we should probably
				 * use the dma transfer function.
L
Linus Torvalds 已提交
2068 2069 2070 2071 2072 2073 2074 2075 2076 2077
				 */
				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:
2078
				shost_printk(KERN_ERR, instance, "unknown phase\n");
2079
				NCR5380_dprint(NDEBUG_ANY, instance);
2080
			} /* switch(phase) */
2081
		} else {
2082
			spin_unlock_irq(&hostdata->lock);
2083
			NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
2084
			spin_lock_irq(&hostdata->lock);
L
Linus Torvalds 已提交
2085
		}
2086
	}
L
Linus Torvalds 已提交
2087 2088 2089 2090 2091
}

/*
 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
 *
2092
 * Purpose : does reselection, initializing the instance->connected
2093 2094
 * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
 * nexus has been reestablished,
2095
 *
L
Linus Torvalds 已提交
2096 2097 2098
 * Inputs : instance - this instance of the NCR5380.
 */

2099 2100
static void NCR5380_reselect(struct Scsi_Host *instance)
{
F
Finn Thain 已提交
2101
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
L
Linus Torvalds 已提交
2102
	unsigned char target_mask;
2103
	unsigned char lun;
L
Linus Torvalds 已提交
2104
	unsigned char msg[3];
2105 2106
	struct NCR5380_cmd *ncmd;
	struct scsi_cmnd *tmp;
L
Linus Torvalds 已提交
2107 2108 2109 2110 2111 2112 2113 2114 2115

	/*
	 * Disable arbitration, etc. since the host adapter obviously
	 * lost, and tell an interrupted NCR5380_select() to restart.
	 */

	NCR5380_write(MODE_REG, MR_BASE);

	target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2116 2117

	dsprintk(NDEBUG_RESELECTION, instance, "reselect\n");
L
Linus Torvalds 已提交
2118

2119
	/*
L
Linus Torvalds 已提交
2120 2121 2122 2123 2124 2125 2126 2127 2128
	 * 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);
2129 2130 2131 2132 2133
	if (NCR5380_poll_politely(instance,
	                          STATUS_REG, SR_SEL, 0, 2 * HZ) < 0) {
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		return;
	}
L
Linus Torvalds 已提交
2134 2135 2136 2137 2138 2139
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	/*
	 * Wait for target to go into MSGIN.
	 */

2140
	if (NCR5380_poll_politely(instance,
2141 2142 2143 2144
	                          STATUS_REG, SR_REQ, SR_REQ, 2 * HZ) < 0) {
		do_abort(instance);
		return;
	}
L
Linus Torvalds 已提交
2145

2146 2147 2148
#ifdef CONFIG_SUN3
	/* acknowledge toggle to MSGIN */
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN));
L
Linus Torvalds 已提交
2149

2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163
	/* peek at the byte without really hitting the bus */
	msg[0] = NCR5380_read(CURRENT_SCSI_DATA_REG);
#else
	{
		int len = 1;
		unsigned char *data = msg;
		unsigned char phase = PHASE_MSGIN;

		NCR5380_transfer_pio(instance, &phase, &len, &data);

		if (len) {
			do_abort(instance);
			return;
		}
2164
	}
2165
#endif /* CONFIG_SUN3 */
2166

L
Linus Torvalds 已提交
2167
	if (!(msg[0] & 0x80)) {
2168
		shost_printk(KERN_ERR, instance, "expecting IDENTIFY message, got ");
2169
		spi_print_msg(msg);
2170 2171 2172 2173 2174
		printk("\n");
		do_abort(instance);
		return;
	}
	lun = msg[0] & 0x07;
L
Linus Torvalds 已提交
2175

2176 2177 2178 2179 2180
	/*
	 * We need to add code for SCSI-II to track which devices have
	 * I_T_L_Q nexuses established, and which have simple I_T_L
	 * nexuses so we can chose to do additional data transfer.
	 */
L
Linus Torvalds 已提交
2181

2182 2183 2184 2185
	/*
	 * 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.
	 */
L
Linus Torvalds 已提交
2186

2187 2188 2189 2190 2191 2192 2193 2194
	tmp = NULL;
	list_for_each_entry(ncmd, &hostdata->disconnected, list) {
		struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd);

		if (target_mask == (1 << scmd_id(cmd)) &&
		    lun == (u8)cmd->device->lun) {
			list_del(&ncmd->list);
			tmp = cmd;
2195
			break;
L
Linus Torvalds 已提交
2196 2197
		}
	}
2198 2199 2200 2201 2202

	if (tmp) {
		dsprintk(NDEBUG_RESELECTION | NDEBUG_QUEUES, instance,
		         "reselect: removed %p from disconnected queue\n", tmp);
	} else {
2203 2204 2205
		shost_printk(KERN_ERR, instance, "target bitmask 0x%02x lun %d not in disconnected queue.\n",
		             target_mask, lun);
		/*
2206 2207
		 * Since we have an established nexus that we can't do anything
		 * with, we must abort it.
2208
		 */
L
Linus Torvalds 已提交
2209
		do_abort(instance);
2210
		return;
L
Linus Torvalds 已提交
2211
	}
2212

2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236
#ifdef CONFIG_SUN3
	{
		void *d;
		unsigned long count;

		if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
			count = tmp->SCp.buffer->length;
			d = sg_virt(tmp->SCp.buffer);
		} else {
			count = tmp->SCp.this_residual;
			d = tmp->SCp.ptr;
		}

		if (sun3_dma_setup_done != tmp &&
		    sun3scsi_dma_xfer_len(count, tmp) > 0) {
			sun3scsi_dma_setup(instance, d, count,
			                   rq_data_dir(tmp->request));
			sun3_dma_setup_done = tmp;
		}
	}

	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
#endif /* CONFIG_SUN3 */

2237 2238 2239 2240
	/* Accept message by clearing ACK */
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	hostdata->connected = tmp;
2241 2242
	dsprintk(NDEBUG_RESELECTION, instance, "nexus established, target %d, lun %llu\n",
	         scmd_id(tmp), tmp->device->lun);
L
Linus Torvalds 已提交
2243 2244
}

2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297
/**
 * list_find_cmd - test for presence of a command in a linked list
 * @haystack: list of commands
 * @needle: command to search for
 */

static bool list_find_cmd(struct list_head *haystack,
                          struct scsi_cmnd *needle)
{
	struct NCR5380_cmd *ncmd;

	list_for_each_entry(ncmd, haystack, list)
		if (NCR5380_to_scmd(ncmd) == needle)
			return true;
	return false;
}

/**
 * list_remove_cmd - remove a command from linked list
 * @haystack: list of commands
 * @needle: command to remove
 */

static bool list_del_cmd(struct list_head *haystack,
                         struct scsi_cmnd *needle)
{
	if (list_find_cmd(haystack, needle)) {
		struct NCR5380_cmd *ncmd = scsi_cmd_priv(needle);

		list_del(&ncmd->list);
		return true;
	}
	return false;
}

/**
 * NCR5380_abort - scsi host eh_abort_handler() method
 * @cmd: the command to be aborted
 *
 * Try to abort a given command by removing it from queues and/or sending
 * the target an abort message. This may not succeed in causing a target
 * to abort the command. Nonetheless, the low-level driver must forget about
 * the command because the mid-layer reclaims it and it may be re-issued.
 *
 * The normal path taken by a command is as follows. For EH we trace this
 * same path to locate and abort the command.
 *
 * unissued -> selecting -> [unissued -> selecting ->]... connected ->
 * [disconnected -> connected ->]...
 * [autosense -> connected ->] done
 *
 * If cmd was not found at all then presumably it has already been completed,
 * in which case return SUCCESS to try to avoid further EH measures.
F
Finn Thain 已提交
2298
 *
2299
 * If the command has not completed yet, we must not fail to find it.
F
Finn Thain 已提交
2300 2301 2302 2303
 * We have no option but to forget the aborted command (even if it still
 * lacks sense data). The mid-layer may re-issue a command that is in error
 * recovery (see scsi_send_eh_cmnd), but the logic and data structures in
 * this driver are such that a command can appear on one queue only.
2304 2305 2306
 *
 * The lock protects driver data structures, but EH handlers also use it
 * to serialize their own execution and prevent their own re-entry.
L
Linus Torvalds 已提交
2307 2308
 */

F
Finn Thain 已提交
2309 2310
static int NCR5380_abort(struct scsi_cmnd *cmd)
{
L
Linus Torvalds 已提交
2311
	struct Scsi_Host *instance = cmd->device->host;
F
Finn Thain 已提交
2312
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
2313
	unsigned long flags;
2314
	int result = SUCCESS;
2315

2316 2317
	spin_lock_irqsave(&hostdata->lock, flags);

2318
#if (NDEBUG & NDEBUG_ANY)
2319
	scmd_printk(KERN_INFO, cmd, __func__);
2320
#endif
2321 2322
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
L
Linus Torvalds 已提交
2323

2324 2325 2326 2327 2328
	if (list_del_cmd(&hostdata->unissued, cmd)) {
		dsprintk(NDEBUG_ABORT, instance,
		         "abort: removed %p from issue queue\n", cmd);
		cmd->result = DID_ABORT << 16;
		cmd->scsi_done(cmd); /* No tag or busy flag to worry about */
F
Finn Thain 已提交
2329
		goto out;
2330 2331
	}

2332 2333 2334 2335 2336 2337 2338 2339 2340
	if (hostdata->selecting == cmd) {
		dsprintk(NDEBUG_ABORT, instance,
		         "abort: cmd %p == selecting\n", cmd);
		hostdata->selecting = NULL;
		cmd->result = DID_ABORT << 16;
		complete_cmd(instance, cmd);
		goto out;
	}

2341 2342 2343
	if (list_del_cmd(&hostdata->disconnected, cmd)) {
		dsprintk(NDEBUG_ABORT, instance,
		         "abort: removed %p from disconnected list\n", cmd);
2344 2345 2346
		/* Can't call NCR5380_select() and send ABORT because that
		 * means releasing the lock. Need a bus reset.
		 */
F
Finn Thain 已提交
2347 2348
		set_host_byte(cmd, DID_ERROR);
		complete_cmd(instance, cmd);
2349 2350
		result = FAILED;
		goto out;
2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363
	}

	if (hostdata->connected == cmd) {
		dsprintk(NDEBUG_ABORT, instance, "abort: cmd %p is connected\n", cmd);
		hostdata->connected = NULL;
		hostdata->dma_len = 0;
		if (do_abort(instance)) {
			set_host_byte(cmd, DID_ERROR);
			complete_cmd(instance, cmd);
			result = FAILED;
			goto out;
		}
		set_host_byte(cmd, DID_ABORT);
F
Finn Thain 已提交
2364 2365 2366 2367 2368 2369 2370 2371
		complete_cmd(instance, cmd);
		goto out;
	}

	if (list_del_cmd(&hostdata->autosense, cmd)) {
		dsprintk(NDEBUG_ABORT, instance,
		         "abort: removed %p from sense queue\n", cmd);
		set_host_byte(cmd, DID_ERROR);
2372 2373 2374 2375 2376 2377 2378 2379 2380 2381
		complete_cmd(instance, cmd);
	}

out:
	if (result == FAILED)
		dsprintk(NDEBUG_ABORT, instance, "abort: failed to abort %p\n", cmd);
	else
		dsprintk(NDEBUG_ABORT, instance, "abort: successfully aborted %p\n", cmd);

	queue_work(hostdata->work_q, &hostdata->main_task);
2382
	maybe_release_dma_irq(instance);
2383
	spin_unlock_irqrestore(&hostdata->lock, flags);
2384

2385
	return result;
L
Linus Torvalds 已提交
2386 2387 2388
}


2389 2390 2391
/**
 * NCR5380_bus_reset - reset the SCSI bus
 * @cmd: SCSI command undergoing EH
L
Linus Torvalds 已提交
2392
 *
2393
 * Returns SUCCESS
L
Linus Torvalds 已提交
2394 2395
 */

F
Finn Thain 已提交
2396
static int NCR5380_bus_reset(struct scsi_cmnd *cmd)
2397 2398
{
	struct Scsi_Host *instance = cmd->device->host;
2399
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
2400
	int i;
2401
	unsigned long flags;
2402
	struct NCR5380_cmd *ncmd;
2403

2404
	spin_lock_irqsave(&hostdata->lock, flags);
2405 2406

#if (NDEBUG & NDEBUG_ANY)
2407
	scmd_printk(KERN_INFO, cmd, __func__);
2408
#endif
2409 2410
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
2411 2412

	do_reset(instance);
2413

2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424
	/* reset NCR registers */
	NCR5380_write(MODE_REG, MR_BASE);
	NCR5380_write(TARGET_COMMAND_REG, 0);
	NCR5380_write(SELECT_ENABLE_REG, 0);

	/* 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!
	 */

2425 2426 2427 2428 2429 2430 2431 2432 2433 2434
	if (list_del_cmd(&hostdata->unissued, cmd)) {
		cmd->result = DID_RESET << 16;
		cmd->scsi_done(cmd);
	}

	if (hostdata->selecting) {
		hostdata->selecting->result = DID_RESET << 16;
		complete_cmd(instance, hostdata->selecting);
		hostdata->selecting = NULL;
	}
2435 2436 2437 2438 2439

	list_for_each_entry(ncmd, &hostdata->disconnected, list) {
		struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd);

		set_host_byte(cmd, DID_RESET);
2440
		complete_cmd(instance, cmd);
2441
	}
2442
	INIT_LIST_HEAD(&hostdata->disconnected);
2443 2444 2445 2446 2447 2448 2449

	list_for_each_entry(ncmd, &hostdata->autosense, list) {
		struct scsi_cmnd *cmd = NCR5380_to_scmd(ncmd);

		set_host_byte(cmd, DID_RESET);
		cmd->scsi_done(cmd);
	}
2450
	INIT_LIST_HEAD(&hostdata->autosense);
2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462

	if (hostdata->connected) {
		set_host_byte(hostdata->connected, DID_RESET);
		complete_cmd(instance, hostdata->connected);
		hostdata->connected = NULL;
	}

	for (i = 0; i < 8; ++i)
		hostdata->busy[i] = 0;
	hostdata->dma_len = 0;

	queue_work(hostdata->work_q, &hostdata->main_task);
2463
	maybe_release_dma_irq(instance);
2464
	spin_unlock_irqrestore(&hostdata->lock, flags);
L
Linus Torvalds 已提交
2465 2466 2467

	return SUCCESS;
}