NCR5380.c 71.8 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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#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);

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	hostdata->flags = flags;
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	INIT_WORK(&hostdata->main_task, NCR5380_main);
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	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);
520 521 522 523 524 525 526 527 528 529 530 531 532 533 534

	/* 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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538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553
/**
 * 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)
{
554
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
555
	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:
562 563 564
			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:
567
			shost_printk(KERN_ERR, instance, "bus busy, attempting abort\n");
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			do_abort(instance);
			break;
		case 4:
571
			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:
583
			shost_printk(KERN_ERR, instance, "bus locked solid\n");
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			return -ENXIO;
		}
	}
	return 0;
}

/**
591
 * NCR5380_exit - remove an NCR5380
592
 * @instance: adapter to remove
593 594
 *
 * Assumes that no more work can be queued (e.g. by NCR5380_intr).
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 */

597
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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601
	cancel_work_sync(&hostdata->main_task);
602
	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);
647
	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:
654
		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;
	}
659
#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;

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	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
671
	 * 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.
	 */

675 676 677 678 679
	if (cmd->cmnd[0] == REQUEST_SENSE)
		list_add(&ncmd->list, &hostdata->unissued);
	else
		list_add_tail(&ncmd->list, &hostdata->unissued);

680
	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 */
686
	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;

720
	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);

753
	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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/**
762
 * 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;
776

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	do {
		done = 1;
779

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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);
788

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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.
			 */
801

802
			if (!NCR5380_select(instance, cmd)) {
803
				dsprintk(NDEBUG_MAIN, instance, "main: select complete\n");
804
				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);
			}
		}
811
		if (hostdata->connected && !hostdata->dma_len) {
812
			dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n");
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			NCR5380_information_transfer(instance);
			done = 0;
815
		}
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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");
			}
		}
	}

853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869
#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

870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904
	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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/**
906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936
 * 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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 */

939
static irqreturn_t __maybe_unused NCR5380_intr(int irq, void *dev_id)
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{
941
	struct Scsi_Host *instance = dev_id;
942 943
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	int handled = 0;
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	unsigned char basr;
	unsigned long flags;

947
	spin_lock_irqsave(&hostdata->lock, flags);
948 949 950 951 952 953

	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);

954 955
		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) &&
973 974 975 976 977
		    (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);

978
			dsprintk(NDEBUG_INTR, instance, "interrupt with SEL and IO\n");
979 980 981 982

			if (!hostdata->connected) {
				NCR5380_reselect(instance);
				queue_work(hostdata->work_q, &hostdata->main_task);
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			}
984 985 986 987 988 989
			if (!hostdata->connected)
				NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
		} else {
			/* Probably Bus Reset */
			NCR5380_read(RESET_PARITY_INTERRUPT_REG);

990
			dsprintk(NDEBUG_INTR, instance, "unknown interrupt\n");
991 992 993
#ifdef SUN3_SCSI_VME
			dregs->csr |= CSR_DMA_ENABLE;
#endif
994 995 996 997
		}
		handled = 1;
	} else {
		shost_printk(KERN_NOTICE, instance, "interrupt without IRQ bit\n");
998 999 1000
#ifdef SUN3_SCSI_VME
		dregs->csr |= CSR_DMA_ENABLE;
#endif
1001 1002
	}

1003
	spin_unlock_irqrestore(&hostdata->lock, flags);
1004 1005

	return IRQ_RETVAL(handled);
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}

1008
/*
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 * Function : int NCR5380_select(struct Scsi_Host *instance,
1010
 * struct scsi_cmnd *cmd)
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 *
 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1013 1014
 * including ARBITRATION, SELECTION, and initial message out for
 * IDENTIFY and queue messages.
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 *
1016
 * Inputs : instance - instantiation of the 5380 driver on which this
1017
 * target lives, cmd - SCSI command to execute.
1018
 *
1019 1020 1021
 * 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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 *
1023
 * Side effects :
1024 1025 1026 1027
 * 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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1028
 *
1029 1030 1031
 * 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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 *
1033 1034
 * 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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 */
1036

1037 1038
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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1041 1042 1043 1044 1045 1046
	unsigned char tmp[3], phase;
	unsigned char *data;
	int len;
	int err;

	NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1047 1048
	dsprintk(NDEBUG_ARBITRATION, instance, "starting arbitration, id = %d\n",
	         instance->this_id);
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1050 1051 1052 1053 1054 1055 1056 1057 1058
	/*
	 * 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;

1059 1060
	/*
	 * 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);

1066
	/*
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	 * Start arbitration.
	 */

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

1073 1074 1075
	/* The chip now waits for BUS FREE phase. Then after the 800 ns
	 * Bus Free Delay, arbitration will begin.
	 */
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1077
	spin_unlock_irq(&hostdata->lock);
1078 1079 1080
	err = NCR5380_poll_politely2(instance, MODE_REG, MR_ARBITRATE, 0,
	                INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS,
	                                       ICR_ARBITRATION_PROGRESS, HZ);
1081
	spin_lock_irq(&hostdata->lock);
1082 1083
	if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
		/* Reselection interrupt */
1084
		goto out;
1085
	}
1086 1087 1088 1089 1090
	if (!hostdata->selecting) {
		/* Command was aborted */
		NCR5380_write(MODE_REG, MR_BASE);
		goto out;
	}
1091 1092 1093 1094
	if (err < 0) {
		NCR5380_write(MODE_REG, MR_BASE);
		shost_printk(KERN_ERR, instance,
		             "select: arbitration timeout\n");
1095
		goto out;
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	}
1097
	spin_unlock_irq(&hostdata->lock);
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1098

1099
	/* The SCSI-2 arbitration delay is 2.4 us */
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	udelay(3);

	/* Check for lost arbitration */
1103 1104 1105
	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);
1107
		dsprintk(NDEBUG_ARBITRATION, instance, "lost arbitration, deasserting MR_ARBITRATE\n");
1108
		spin_lock_irq(&hostdata->lock);
1109
		goto out;
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	}
1111 1112 1113 1114 1115 1116 1117

	/* 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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1119 1120
	/*
	 * 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)
	 */

1124 1125 1126 1127
	if (hostdata->flags & FLAG_TOSHIBA_DELAY)
		udelay(15);
	else
		udelay(2);
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1129 1130
	spin_lock_irq(&hostdata->lock);

1131 1132
	/* NCR5380_reselect() clears MODE_REG after a reselection interrupt */
	if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE))
1133 1134 1135 1136 1137 1138 1139
		goto out;

	if (!hostdata->selecting) {
		NCR5380_write(MODE_REG, MR_BASE);
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		goto out;
	}
1140

1141
	dsprintk(NDEBUG_ARBITRATION, instance, "won arbitration\n");
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1142

1143 1144
	/*
	 * Now that we have won arbitration, start Selection process, asserting
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	 * the host and target ID's on the SCSI bus.
	 */

1148
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask | (1 << scmd_id(cmd)));
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1150
	/*
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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.
	 */

1156 1157
	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);

1160
	/*
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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);

1166 1167
	spin_unlock_irq(&hostdata->lock);

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1168
	/*
1169
	 * The initiator shall then wait at least two deskew delays and release
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1170 1171
	 * the BSY signal.
	 */
1172
	udelay(1);        /* wingel -- wait two bus deskew delay >2*45ns */
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1173 1174

	/* Reset BSY */
1175 1176
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA |
	              ICR_ASSERT_ATN | ICR_ASSERT_SEL);
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1177

1178
	/*
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1179
	 * Something weird happens when we cease to drive BSY - looks
1180
	 * like the board/chip is letting us do another read before the
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1181 1182 1183 1184 1185
	 * 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
1186 1187 1188
	 * 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);

1197
	dsprintk(NDEBUG_SELECTION, instance, "selecting target %d\n", scmd_id(cmd));
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1198

1199 1200
	/*
	 * 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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1206 1207

	if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1208
		spin_lock_irq(&hostdata->lock);
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		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		NCR5380_reselect(instance);
1211 1212
		if (!hostdata->connected)
			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1213
		shost_printk(KERN_ERR, instance, "reselection after won arbitration?\n");
1214
		goto out;
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1215
	}
F
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1216 1217

	if (err < 0) {
1218
		spin_lock_irq(&hostdata->lock);
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1219 1220
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1221 1222 1223 1224 1225 1226 1227 1228
		/* 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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1229 1230
	}

1231 1232 1233
	/*
	 * 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);

	/*
1242
	 * 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);
1251
	spin_lock_irq(&hostdata->lock);
1252
	if (err < 0) {
1253 1254
		shost_printk(KERN_ERR, instance, "select: REQ timeout\n");
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
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1255
		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1256 1257 1258 1259 1260
		goto out;
	}
	if (!hostdata->selecting) {
		do_abort(instance);
		goto out;
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1261 1262
	}

1263 1264
	dsprintk(NDEBUG_SELECTION, instance, "target %d selected, going into MESSAGE OUT phase.\n",
	         scmd_id(cmd));
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1265
	tmp[0] = IDENTIFY(((instance->irq == NO_IRQ) ? 0 : 1), cmd->device->lun);
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1266 1267 1268 1269 1270

	len = 1;
	data = tmp;
	phase = PHASE_MSGOUT;
	NCR5380_transfer_pio(instance, &phase, &len, &data);
1271
	dsprintk(NDEBUG_SELECTION, instance, "nexus established.\n");
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	/* XXX need to handle errors here */
1273

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1274
	hostdata->connected = cmd;
1275
	hostdata->busy[cmd->device->id] |= 1 << cmd->device->lun;
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1276

1277 1278 1279 1280
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif

1281
	initialize_SCp(cmd);
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1282

1283 1284 1285 1286 1287 1288 1289
	cmd = NULL;

out:
	if (!hostdata->selecting)
		return NULL;
	hostdata->selecting = NULL;
	return cmd;
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1290 1291
}

1292 1293
/*
 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1294
 * unsigned char *phase, int *count, unsigned char **data)
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1295 1296 1297
 *
 * Purpose : transfers data in given phase using polled I/O
 *
1298
 * Inputs : instance - instance of driver, *phase - pointer to
1299 1300
 * what phase is expected, *count - pointer to number of
 * bytes to transfer, **data - pointer to data pointer.
1301
 *
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1302
 * Returns : -1 when different phase is entered without transferring
1303
 * maximum number of bytes, 0 if all bytes are transferred or exit
1304
 * is in same phase.
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1305
 *
1306
 * Also, *phase, *count, *data are modified in place.
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 *
 * XXX Note : handling for bus free may be useful.
 */

/*
1312
 * 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.
 */

1317 1318 1319 1320
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;

1325 1326
	/*
	 * 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
	 */

1331
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
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1332 1333

	do {
1334 1335 1336
		/*
		 * Wait for assertion of REQ, after which the phase bits will be
		 * valid
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1337 1338
		 */

1339
		if (NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ) < 0)
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1340 1341
			break;

1342
		dsprintk(NDEBUG_HANDSHAKE, instance, "REQ asserted\n");
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1343 1344

		/* Check for phase mismatch */
1345
		if ((NCR5380_read(STATUS_REG) & PHASE_MASK) != p) {
1346 1347
			dsprintk(NDEBUG_PIO, instance, "phase mismatch\n");
			NCR5380_dprint_phase(NDEBUG_PIO, instance);
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1348 1349
			break;
		}
1350

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1351 1352 1353 1354 1355 1356 1357 1358
		/* 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;

1359
		/*
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1360 1361 1362 1363 1364 1365 1366 1367 1368 1369
		 * 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);
1370 1371
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ACK);
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1372
			} else {
1373 1374
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ATN);
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1375
				NCR5380_dprint(NDEBUG_PIO, instance);
1376 1377
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
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1378 1379 1380 1381 1382 1383
			}
		} else {
			NCR5380_dprint(NDEBUG_PIO, instance);
			NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
		}

1384 1385 1386 1387
		if (NCR5380_poll_politely(instance,
		                          STATUS_REG, SR_REQ, 0, 5 * HZ) < 0)
			break;

1388
		dsprintk(NDEBUG_HANDSHAKE, instance, "REQ negated, handshake complete\n");
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1389 1390

/*
1391 1392
 * 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
1393
 * message.  ATN must be dropped as ACK is dropped.
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1394
 *
1395
 * 2.  We are in a MSGIN phase, and we are on the last byte of the
1396 1397
 * 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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1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408
 *
 * 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);

1409
	dsprintk(NDEBUG_PIO, instance, "residual %d\n", c);
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1410 1411 1412 1413

	*count = c;
	*data = d;
	tmp = NCR5380_read(STATUS_REG);
1414 1415 1416 1417 1418
	/* 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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1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429
		*phase = tmp & PHASE_MASK;
	else
		*phase = PHASE_UNKNOWN;

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

/**
1430 1431
 * do_reset - issue a reset command
 * @instance: adapter to reset
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1432
 *
1433 1434
 * Issue a reset sequence to the NCR5380 and try and get the bus
 * back into sane shape.
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1435
 *
1436 1437 1438
 * 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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1439
 */
1440

1441 1442
static void do_reset(struct Scsi_Host *instance)
{
1443 1444 1445 1446 1447
	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);
1449
	udelay(50);
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1450
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1451 1452
	(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
	local_irq_restore(flags);
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}

1455 1456 1457 1458
/**
 * 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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1459
 *
1460
 * Returns 0 on success, -1 on failure.
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1461 1462
 */

1463 1464
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);

1472 1473 1474 1475
	/*
	 * 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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1476
	 * other phase and will have to source/sink data.
1477
	 *
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1478 1479 1480 1481
	 * We really don't care what value was on the bus or what value
	 * the target sees, so we just handshake.
	 */

1482
	rc = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 10 * HZ);
1483
	if (rc < 0)
1484
		goto timeout;
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1485

1486
	tmp = NCR5380_read(STATUS_REG) & PHASE_MASK;
1487

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1488 1489
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

1490
	if (tmp != PHASE_MSGOUT) {
1491 1492
		NCR5380_write(INITIATOR_COMMAND_REG,
		              ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1493
		rc = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 3 * HZ);
1494
		if (rc < 0)
1495 1496
			goto timeout;
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
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1497
	}
1498

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	tmp = ABORT;
	msgptr = &tmp;
	len = 1;
	phase = PHASE_MSGOUT;
1503
	NCR5380_transfer_pio(instance, &phase, &len, &msgptr);
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1504 1505 1506 1507 1508 1509 1510

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

	return len ? -1 : 0;
1511 1512 1513 1514

timeout:
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
	return -1;
L
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1515 1516
}

1517 1518
/*
 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1519
 * unsigned char *phase, int *count, unsigned char **data)
L
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1520 1521
 *
 * Purpose : transfers data in given phase using either real
1522
 * or pseudo DMA.
L
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1523
 *
1524
 * Inputs : instance - instance of driver, *phase - pointer to
1525 1526
 * what phase is expected, *count - pointer to number of
 * bytes to transfer, **data - pointer to data pointer.
1527
 *
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1528
 * Returns : -1 when different phase is entered without transferring
1529 1530
 * maximum number of bytes, 0 if all bytes or transferred or exit
 * is in same phase.
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1531
 *
1532
 * Also, *phase, *count, *data are modified in place.
L
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1533 1534 1535
 */


1536 1537 1538 1539 1540
static int NCR5380_transfer_dma(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
1541 1542 1543
	int c = *count;
	unsigned char p = *phase;
	unsigned char *d = *data;
L
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1544
	unsigned char tmp;
1545
	int result = 0;
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1546 1547 1548 1549 1550 1551

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

1552
	hostdata->connected->SCp.phase = p;
L
Linus Torvalds 已提交
1553

1554 1555 1556 1557 1558 1559
	if (p & SR_IO) {
		if (hostdata->read_overruns)
			c -= hostdata->read_overruns;
		else if (hostdata->flags & FLAG_DMA_FIXUP)
			--c;
	}
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1560

1561 1562
	dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n",
	         (p & SR_IO) ? "receive" : "send", c, d);
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1563

1564 1565 1566 1567 1568
#ifdef CONFIG_SUN3
	/* send start chain */
	sun3scsi_dma_start(c, *data);
#endif

1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581
	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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1582

1583
	/*
1584 1585
	 * On the PAS16 at least I/O recovery delays are not needed here.
	 * Everyone else seems to want them.
L
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1586 1587 1588
	 */

	if (p & SR_IO) {
1589
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1590
		NCR5380_io_delay(1);
L
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1591 1592
		NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
	} else {
1593
		NCR5380_io_delay(1);
L
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1594
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1595
		NCR5380_io_delay(1);
L
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1596
		NCR5380_write(START_DMA_SEND_REG, 0);
1597
		NCR5380_io_delay(1);
L
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1598 1599
	}

1600 1601 1602 1603 1604 1605 1606
#ifdef CONFIG_SUN3
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_DMA_ENABLE;
#endif
	sun3_dma_active = 1;
#endif

1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629
	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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1630
/*
1631
 * A note regarding the DMA errata workarounds for early NMOS silicon.
F
Finn Thain 已提交
1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657
 *
 * 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
1658
 * problem.  The chosen fix is to DMA fewer bytes, then check for the
F
Finn Thain 已提交
1659 1660 1661
 * 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
1662 1663
 */

1664 1665
	if (hostdata->flags & FLAG_DMA_FIXUP) {
		if (p & SR_IO) {
L
Linus Torvalds 已提交
1666
			/*
1667
			 * The workaround was to transfer fewer bytes than we
1668
			 * intended to with the pseudo-DMA read function, wait for
L
Linus Torvalds 已提交
1669 1670
			 * the chip to latch the last byte, read it, and then disable
			 * pseudo-DMA mode.
1671
			 *
L
Linus Torvalds 已提交
1672 1673 1674 1675
			 * 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
1676 1677
			 * 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
1678 1679 1680
			 * byte.
			 */

1681 1682
			if (NCR5380_poll_politely(instance, BUS_AND_STATUS_REG,
			                          BASR_DRQ, BASR_DRQ, HZ) < 0) {
1683
				result = -1;
1684 1685 1686 1687
				shost_printk(KERN_ERR, instance, "PDMA read: DRQ timeout\n");
			}
			if (NCR5380_poll_politely(instance, STATUS_REG,
			                          SR_REQ, 0, HZ) < 0) {
1688
				result = -1;
1689
				shost_printk(KERN_ERR, instance, "PDMA read: !REQ timeout\n");
L
Linus Torvalds 已提交
1690
			}
1691 1692
			d[*count - 1] = NCR5380_read(INPUT_DATA_REG);
		} else {
L
Linus Torvalds 已提交
1693
			/*
1694 1695
			 * 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
1696
			 */
1697 1698 1699
			if (NCR5380_poll_politely2(instance,
			     BUS_AND_STATUS_REG, BASR_DRQ, BASR_DRQ,
			     BUS_AND_STATUS_REG, BASR_PHASE_MATCH, 0, HZ) < 0) {
1700
				result = -1;
1701
				shost_printk(KERN_ERR, instance, "PDMA write: DRQ and phase timeout\n");
L
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1702 1703 1704
			}
		}
	}
1705 1706

	NCR5380_dma_complete(instance);
1707
	return result;
L
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1708 1709 1710 1711 1712
}

/*
 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
 *
1713
 * Purpose : run through the various SCSI phases and do as the target
1714 1715
 * directs us to.  Operates on the currently connected command,
 * instance->connected.
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1716 1717 1718
 *
 * Inputs : instance, instance for which we are doing commands
 *
1719
 * Side effects : SCSI things happen, the disconnected queue will be
1720 1721
 * modified if a command disconnects, *instance->connected will
 * change.
L
Linus Torvalds 已提交
1722
 *
1723
 * XXX Note : we need to watch for bus free or a reset condition here
1724
 * to recover from an unexpected bus free condition.
L
Linus Torvalds 已提交
1725 1726
 */

1727 1728
static void NCR5380_information_transfer(struct Scsi_Host *instance)
{
F
Finn Thain 已提交
1729
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
L
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1730 1731 1732 1733 1734 1735
	unsigned char msgout = NOP;
	int sink = 0;
	int len;
	int transfersize;
	unsigned char *data;
	unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
1736
	struct scsi_cmnd *cmd;
L
Linus Torvalds 已提交
1737

1738 1739 1740 1741
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif

1742
	while ((cmd = hostdata->connected)) {
1743 1744
		struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);

L
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1745 1746 1747 1748 1749 1750 1751 1752
		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);
			}
1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777
#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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1778 1779 1780
			if (sink && (phase != PHASE_MSGOUT)) {
				NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

1781 1782
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
				              ICR_ASSERT_ACK);
1783 1784
				while (NCR5380_read(STATUS_REG) & SR_REQ)
					;
1785 1786
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_ATN);
L
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1787 1788 1789
				sink = 0;
				continue;
			}
1790

L
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1791 1792 1793
			switch (phase) {
			case PHASE_DATAOUT:
#if (NDEBUG & NDEBUG_NO_DATAOUT)
1794
				shost_printk(KERN_DEBUG, instance, "NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n");
L
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1795 1796 1797
				sink = 1;
				do_abort(instance);
				cmd->result = DID_ERROR << 16;
1798
				complete_cmd(instance, cmd);
F
Finn Thain 已提交
1799
				hostdata->connected = NULL;
L
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1800 1801
				return;
#endif
F
Finn Thain 已提交
1802
			case PHASE_DATAIN:
1803
				/*
L
Linus Torvalds 已提交
1804 1805 1806 1807 1808 1809 1810 1811
				 * 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
1812
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
1813 1814 1815
					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
1816
				}
1817

L
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1818
				/*
1819
				 * The preferred transfer method is going to be
L
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1820 1821 1822 1823 1824 1825 1826 1827
				 * 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.
				 */

1828
				transfersize = 0;
1829
				if (!cmd->device->borken)
1830 1831
					transfersize = NCR5380_dma_xfer_len(instance, cmd, phase);

1832
				if (transfersize > 0) {
L
Linus Torvalds 已提交
1833
					len = transfersize;
1834 1835
					if (NCR5380_transfer_dma(instance, &phase,
					    &len, (unsigned char **)&cmd->SCp.ptr)) {
L
Linus Torvalds 已提交
1836
						/*
1837 1838 1839
						 * If the watchdog timer fires, all future
						 * accesses to this device will use the
						 * polled-IO.
L
Linus Torvalds 已提交
1840
						 */
J
Jeff Garzik 已提交
1841
						scmd_printk(KERN_INFO, cmd,
1842
							"switching to slow handshake\n");
L
Linus Torvalds 已提交
1843 1844 1845 1846 1847
						cmd->device->borken = 1;
						sink = 1;
						do_abort(instance);
						cmd->result = DID_ERROR << 16;
						/* XXX - need to source or sink data here, as appropriate */
1848
					}
F
Finn Thain 已提交
1849
				} else {
1850 1851 1852 1853 1854 1855 1856
					/* 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,
1857
					                     (unsigned char **)&cmd->SCp.ptr);
1858
					cmd->SCp.this_residual -= transfersize - len;
1859
				}
1860 1861 1862 1863
#ifdef CONFIG_SUN3
				if (sun3_dma_setup_done == cmd)
					sun3_dma_setup_done = NULL;
#endif
1864
				return;
L
Linus Torvalds 已提交
1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876
			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);
1877 1878 1879 1880
					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
1881 1882
					hostdata->connected = NULL;

F
Finn Thain 已提交
1883 1884 1885
					cmd->result &= ~0xffff;
					cmd->result |= cmd->SCp.Status;
					cmd->result |= cmd->SCp.Message << 8;
1886

F
Finn Thain 已提交
1887
					if (cmd->cmnd[0] == REQUEST_SENSE)
1888
						complete_cmd(instance, cmd);
F
Finn Thain 已提交
1889 1890 1891 1892 1893 1894 1895 1896 1897
					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
1898 1899
					}

1900 1901
					/*
					 * Restore phase bits to 0 so an interrupted selection,
L
Linus Torvalds 已提交
1902 1903 1904
					 * arbitration can resume.
					 */
					NCR5380_write(TARGET_COMMAND_REG, 0);
1905 1906 1907

					/* Enable reselect interrupts */
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1908 1909

					maybe_release_dma_irq(instance);
L
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1910 1911 1912 1913 1914 1915 1916 1917 1918
					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
1919
						hostdata->busy[cmd->device->id] |= (1 << (cmd->device->lun & 0xFF));
L
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1920 1921 1922 1923
						break;
					default:
						break;
					}
1924
					break;
1925 1926 1927 1928 1929 1930 1931 1932
				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);
1933

1934 1935 1936 1937 1938
					/*
					 * Restore phase bits to 0 so an interrupted selection,
					 * arbitration can resume.
					 */
					NCR5380_write(TARGET_COMMAND_REG, 0);
L
Linus Torvalds 已提交
1939

1940 1941
					/* Enable reselect interrupts */
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1942 1943 1944
#ifdef SUN3_SCSI_VME
					dregs->csr |= CSR_DMA_ENABLE;
#endif
1945
					return;
1946
					/*
L
Linus Torvalds 已提交
1947
					 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
1948
					 * operation, in violation of the SCSI spec so we can safely
L
Linus Torvalds 已提交
1949 1950
					 * ignore SAVE/RESTORE pointers calls.
					 *
1951
					 * Unfortunately, some disks violate the SCSI spec and
L
Linus Torvalds 已提交
1952
					 * don't issue the required SAVE_POINTERS message before
1953
					 * disconnecting, and we have to break spec to remain
L
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1954 1955 1956 1957 1958 1959 1960 1961
					 * 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
1962 1963 1964 1965
					/*
					 * Start the message buffer with the EXTENDED_MESSAGE
					 * byte, since spi_print_msg() wants the whole thing.
					 */
L
Linus Torvalds 已提交
1966 1967 1968
					extended_msg[0] = EXTENDED_MESSAGE;
					/* Accept first byte by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1969 1970 1971

					spin_unlock_irq(&hostdata->lock);

1972
					dsprintk(NDEBUG_EXTENDED, instance, "receiving extended message\n");
L
Linus Torvalds 已提交
1973 1974 1975 1976 1977

					len = 2;
					data = extended_msg + 1;
					phase = PHASE_MSGIN;
					NCR5380_transfer_pio(instance, &phase, &len, &data);
1978 1979 1980
					dsprintk(NDEBUG_EXTENDED, instance, "length %d, code 0x%02x\n",
					         (int)extended_msg[1],
					         (int)extended_msg[2]);
L
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1981

1982 1983
					if (!len && extended_msg[1] > 0 &&
					    extended_msg[1] <= sizeof(extended_msg) - 2) {
L
Linus Torvalds 已提交
1984 1985 1986 1987 1988 1989 1990
						/* 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);
1991 1992
						dsprintk(NDEBUG_EXTENDED, instance, "message received, residual %d\n",
						         len);
L
Linus Torvalds 已提交
1993 1994 1995 1996 1997 1998 1999 2000 2001

						switch (extended_msg[2]) {
						case EXTENDED_SDTR:
						case EXTENDED_WDTR:
						case EXTENDED_MODIFY_DATA_POINTER:
						case EXTENDED_EXTENDED_IDENTIFY:
							tmp = 0;
						}
					} else if (len) {
2002
						shost_printk(KERN_ERR, instance, "error receiving extended message\n");
L
Linus Torvalds 已提交
2003 2004
						tmp = 0;
					} else {
2005 2006
						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
2007 2008
						tmp = 0;
					}
2009 2010 2011 2012 2013

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

L
Linus Torvalds 已提交
2014 2015
					/* Fall through to reject message */

2016 2017
					/*
					 * If we get something weird that we aren't expecting,
L
Linus Torvalds 已提交
2018 2019 2020 2021
					 * reject it.
					 */
				default:
					if (!tmp) {
2022
						shost_printk(KERN_ERR, instance, "rejecting message ");
2023
						spi_print_msg(extended_msg);
L
Linus Torvalds 已提交
2024 2025
						printk("\n");
					} else if (tmp != EXTENDED_MESSAGE)
J
Jeff Garzik 已提交
2026
						scmd_printk(KERN_INFO, cmd,
2027 2028
						            "rejecting unknown message %02x\n",
						            tmp);
L
Linus Torvalds 已提交
2029
					else
J
Jeff Garzik 已提交
2030
						scmd_printk(KERN_INFO, cmd,
2031 2032
						            "rejecting unknown extended message code %02x, length %d\n",
						            extended_msg[1], extended_msg[0]);
L
Linus Torvalds 已提交
2033 2034 2035 2036

					msgout = MESSAGE_REJECT;
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
					break;
2037
				} /* switch (tmp) */
L
Linus Torvalds 已提交
2038 2039 2040 2041 2042 2043 2044 2045 2046
				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;
2047
					complete_cmd(instance, cmd);
2048
					maybe_release_dma_irq(instance);
L
Linus Torvalds 已提交
2049 2050 2051 2052 2053 2054 2055 2056
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
					return;
				}
				msgout = NOP;
				break;
			case PHASE_CMDOUT:
				len = cmd->cmd_len;
				data = cmd->cmnd;
2057 2058 2059 2060
				/*
				 * 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
2061 2062 2063 2064 2065 2066 2067 2068 2069 2070
				 */
				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:
2071
				shost_printk(KERN_ERR, instance, "unknown phase\n");
2072
				NCR5380_dprint(NDEBUG_ANY, instance);
2073
			} /* switch(phase) */
2074
		} else {
2075
			spin_unlock_irq(&hostdata->lock);
2076
			NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
2077
			spin_lock_irq(&hostdata->lock);
L
Linus Torvalds 已提交
2078
		}
2079
	}
L
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2080 2081 2082 2083 2084
}

/*
 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
 *
2085
 * Purpose : does reselection, initializing the instance->connected
2086 2087
 * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
 * nexus has been reestablished,
2088
 *
L
Linus Torvalds 已提交
2089 2090 2091
 * Inputs : instance - this instance of the NCR5380.
 */

2092 2093
static void NCR5380_reselect(struct Scsi_Host *instance)
{
F
Finn Thain 已提交
2094
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
L
Linus Torvalds 已提交
2095
	unsigned char target_mask;
2096
	unsigned char lun;
L
Linus Torvalds 已提交
2097
	unsigned char msg[3];
2098 2099
	struct NCR5380_cmd *ncmd;
	struct scsi_cmnd *tmp;
L
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2100 2101 2102 2103 2104 2105 2106 2107 2108

	/*
	 * 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);
2109 2110

	dsprintk(NDEBUG_RESELECTION, instance, "reselect\n");
L
Linus Torvalds 已提交
2111

2112
	/*
L
Linus Torvalds 已提交
2113 2114 2115 2116 2117 2118 2119 2120 2121
	 * 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);
2122 2123 2124 2125 2126
	if (NCR5380_poll_politely(instance,
	                          STATUS_REG, SR_SEL, 0, 2 * HZ) < 0) {
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		return;
	}
L
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2127 2128 2129 2130 2131 2132
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

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

2133
	if (NCR5380_poll_politely(instance,
2134 2135 2136 2137
	                          STATUS_REG, SR_REQ, SR_REQ, 2 * HZ) < 0) {
		do_abort(instance);
		return;
	}
L
Linus Torvalds 已提交
2138

2139 2140 2141
#ifdef CONFIG_SUN3
	/* acknowledge toggle to MSGIN */
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN));
L
Linus Torvalds 已提交
2142

2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156
	/* 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;
		}
2157
	}
2158
#endif /* CONFIG_SUN3 */
2159

L
Linus Torvalds 已提交
2160
	if (!(msg[0] & 0x80)) {
2161
		shost_printk(KERN_ERR, instance, "expecting IDENTIFY message, got ");
2162
		spi_print_msg(msg);
2163 2164 2165 2166 2167
		printk("\n");
		do_abort(instance);
		return;
	}
	lun = msg[0] & 0x07;
L
Linus Torvalds 已提交
2168

2169 2170 2171 2172 2173
	/*
	 * 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
2174

2175 2176 2177 2178
	/*
	 * 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
2179

2180 2181 2182 2183 2184 2185 2186 2187
	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;
2188
			break;
L
Linus Torvalds 已提交
2189 2190
		}
	}
2191 2192 2193 2194 2195

	if (tmp) {
		dsprintk(NDEBUG_RESELECTION | NDEBUG_QUEUES, instance,
		         "reselect: removed %p from disconnected queue\n", tmp);
	} else {
2196 2197 2198
		shost_printk(KERN_ERR, instance, "target bitmask 0x%02x lun %d not in disconnected queue.\n",
		             target_mask, lun);
		/*
2199 2200
		 * Since we have an established nexus that we can't do anything
		 * with, we must abort it.
2201
		 */
L
Linus Torvalds 已提交
2202
		do_abort(instance);
2203
		return;
L
Linus Torvalds 已提交
2204
	}
2205

2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229
#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 */

2230 2231 2232 2233
	/* Accept message by clearing ACK */
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	hostdata->connected = tmp;
2234 2235
	dsprintk(NDEBUG_RESELECTION, instance, "nexus established, target %d, lun %llu\n",
	         scmd_id(tmp), tmp->device->lun);
L
Linus Torvalds 已提交
2236 2237
}

2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290
/**
 * 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
2291
 *
2292
 * If the command has not completed yet, we must not fail to find it.
F
Finn Thain 已提交
2293 2294 2295 2296
 * 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.
2297 2298 2299
 *
 * 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
2300 2301
 */

F
Finn Thain 已提交
2302 2303
static int NCR5380_abort(struct scsi_cmnd *cmd)
{
L
Linus Torvalds 已提交
2304
	struct Scsi_Host *instance = cmd->device->host;
F
Finn Thain 已提交
2305
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
2306
	unsigned long flags;
2307
	int result = SUCCESS;
2308

2309 2310
	spin_lock_irqsave(&hostdata->lock, flags);

2311
#if (NDEBUG & NDEBUG_ANY)
2312
	scmd_printk(KERN_INFO, cmd, __func__);
2313
#endif
2314 2315
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
L
Linus Torvalds 已提交
2316

2317 2318 2319 2320 2321
	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
2322
		goto out;
2323 2324
	}

2325 2326 2327 2328 2329 2330 2331 2332 2333
	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;
	}

2334 2335 2336
	if (list_del_cmd(&hostdata->disconnected, cmd)) {
		dsprintk(NDEBUG_ABORT, instance,
		         "abort: removed %p from disconnected list\n", cmd);
2337 2338 2339
		/* Can't call NCR5380_select() and send ABORT because that
		 * means releasing the lock. Need a bus reset.
		 */
F
Finn Thain 已提交
2340 2341
		set_host_byte(cmd, DID_ERROR);
		complete_cmd(instance, cmd);
2342 2343
		result = FAILED;
		goto out;
2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356
	}

	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
2357 2358 2359 2360 2361 2362 2363 2364
		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);
2365 2366 2367 2368 2369 2370 2371 2372 2373 2374
		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);
2375
	maybe_release_dma_irq(instance);
2376
	spin_unlock_irqrestore(&hostdata->lock, flags);
2377

2378
	return result;
L
Linus Torvalds 已提交
2379 2380 2381
}


2382 2383 2384
/**
 * NCR5380_bus_reset - reset the SCSI bus
 * @cmd: SCSI command undergoing EH
L
Linus Torvalds 已提交
2385
 *
2386
 * Returns SUCCESS
L
Linus Torvalds 已提交
2387 2388
 */

F
Finn Thain 已提交
2389
static int NCR5380_bus_reset(struct scsi_cmnd *cmd)
2390 2391
{
	struct Scsi_Host *instance = cmd->device->host;
2392
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
2393
	int i;
2394
	unsigned long flags;
2395
	struct NCR5380_cmd *ncmd;
2396

2397
	spin_lock_irqsave(&hostdata->lock, flags);
2398 2399

#if (NDEBUG & NDEBUG_ANY)
2400
	scmd_printk(KERN_INFO, cmd, __func__);
2401
#endif
2402 2403
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
2404 2405

	do_reset(instance);
2406

2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417
	/* 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!
	 */

2418 2419 2420 2421 2422 2423 2424 2425 2426 2427
	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;
	}
2428 2429 2430 2431 2432

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

		set_host_byte(cmd, DID_RESET);
2433
		complete_cmd(instance, cmd);
2434
	}
2435
	INIT_LIST_HEAD(&hostdata->disconnected);
2436 2437 2438 2439 2440 2441 2442

	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);
	}
2443
	INIT_LIST_HEAD(&hostdata->autosense);
2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455

	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);
2456
	maybe_release_dma_irq(instance);
2457
	spin_unlock_irqrestore(&hostdata->lock, flags);
L
Linus Torvalds 已提交
2458 2459 2460

	return SUCCESS;
}