NCR5380.c 69.8 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.
 *
 * 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
 *
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 * NCR5380_dma_xfer_len   - determine size of DMA/PDMA transfer
 * NCR5380_dma_send_setup - execute DMA/PDMA from memory to 5380
 * NCR5380_dma_recv_setup - execute DMA/PDMA from 5380 to memory
 * NCR5380_dma_residual   - residual byte count
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 *
 * The generic driver is initialized by calling NCR5380_init(instance),
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 * after setting the appropriate host specific fields and ID.
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 */

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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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 * @hostdata: host private data
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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 NCR5380_hostdata *hostdata,
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                                  unsigned int reg1, u8 bit1, u8 val1,
                                  unsigned int reg2, u8 bit2, u8 val2,
                                  unsigned long wait)
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{
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	unsigned long n = hostdata->poll_loops;
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	unsigned long deadline = jiffies + wait;

	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)
{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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	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)
{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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	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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 * NCR5380_info - report driver and host information
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 * @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;
}

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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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	unsigned long accesses_per_ms;
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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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	snprintf(hostdata->info, sizeof(hostdata->info),
		"%s, irq %d, io_port 0x%lx, base 0x%lx, can_queue %d, cmd_per_lun %d, sg_tablesize %d, this_id %d, flags { %s%s%s}",
		instance->hostt->name, instance->irq, hostdata->io_port,
		hostdata->base, instance->can_queue, instance->cmd_per_lun,
		instance->sg_tablesize, instance->this_id,
		hostdata->flags & FLAG_DMA_FIXUP     ? "DMA_FIXUP "     : "",
		hostdata->flags & FLAG_NO_PSEUDO_DMA ? "NO_PSEUDO_DMA " : "",
		hostdata->flags & FLAG_TOSHIBA_DELAY ? "TOSHIBA_DELAY " : "");
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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);
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	/* 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));
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	accesses_per_ms = i / 256;
	hostdata->poll_loops = NCR5380_REG_POLL_TIME * accesses_per_ms / 2;
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	return 0;
}
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/**
 * NCR5380_maybe_reset_bus - Detect and correct bus wedge problems.
 * @instance: adapter to check
 *
 * If the system crashed, it may have crashed with a connected target and
 * the SCSI bus busy. Check for BUS FREE phase. If not, try to abort the
 * currently established nexus, which we know nothing about. Failing that
 * do a bus reset.
 *
 * Note that a bus reset will cause the chip to assert IRQ.
 *
 * Returns 0 if successful, otherwise -ENXIO.
 */

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

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

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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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	cancel_work_sync(&hostdata->main_task);
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	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;
	}

523 524 525 526 527
	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);
542
	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:
549
		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;
	}
554
#endif /* (NDEBUG & NDEBUG_NO_WRITE) */
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	cmd->result = 0;

558 559 560
	if (!NCR5380_acquire_dma_irq(instance))
		return SCSI_MLQUEUE_HOST_BUSY;

561
	spin_lock_irqsave(&hostdata->lock, flags);
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563 564
	/*
	 * 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
566
	 * 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.
	 */

570 571 572 573 574
	if (cmd->cmnd[0] == REQUEST_SENSE)
		list_add(&ncmd->list, &hostdata->unissued);
	else
		list_add_tail(&ncmd->list, &hostdata->unissued);

575
	spin_unlock_irqrestore(&hostdata->lock, flags);
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577 578
	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 */
581
	queue_work(hostdata->work_q, &hostdata->main_task);
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	return 0;
}

585 586 587 588 589 590 591 592 593
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 &&
594
	    !hostdata->selecting) {
595
		NCR5380_release_dma_irq(instance);
596
	}
597 598
}

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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;

616
	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);

649
	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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/**
658
 * NCR5380_main - NCR state machines
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 *
660 661 662 663
 * 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 =
669
		container_of(work, struct NCR5380_hostdata, main_task);
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	struct Scsi_Host *instance = hostdata->host;
	int done;
672

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	do {
		done = 1;
675

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		spin_lock_irq(&hostdata->lock);
677 678 679 680 681
		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);
684

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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.
			 */
697

698
			if (!NCR5380_select(instance, cmd)) {
699
				dsprintk(NDEBUG_MAIN, instance, "main: select complete\n");
700
				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);
			}
		}
707
		if (hostdata->connected && !hostdata->dma_len) {
708
			dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n");
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			NCR5380_information_transfer(instance);
			done = 0;
711
		}
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		spin_unlock_irq(&hostdata->lock);
		if (!done)
			cond_resched();
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	} while (!done);
}

718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748
/*
 * 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");
			}
		}
	}

749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765
#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

766 767 768 769
	NCR5380_write(MODE_REG, MR_BASE);
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
	NCR5380_read(RESET_PARITY_INTERRUPT_REG);

770
	transferred = hostdata->dma_len - NCR5380_dma_residual(hostdata);
771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800
	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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/**
802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832
 * 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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 */

835
static irqreturn_t __maybe_unused NCR5380_intr(int irq, void *dev_id)
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{
837
	struct Scsi_Host *instance = dev_id;
838 839
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	int handled = 0;
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	unsigned char basr;
	unsigned long flags;

843
	spin_lock_irqsave(&hostdata->lock, flags);
844 845 846 847 848 849

	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);

850 851
		dsprintk(NDEBUG_INTR, instance, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n",
		         irq, basr, sr, mr);
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853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868
		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) &&
869 870 871 872 873
		    (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);

874
			dsprintk(NDEBUG_INTR, instance, "interrupt with SEL and IO\n");
875 876 877 878

			if (!hostdata->connected) {
				NCR5380_reselect(instance);
				queue_work(hostdata->work_q, &hostdata->main_task);
L
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879
			}
880 881 882 883 884 885
			if (!hostdata->connected)
				NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
		} else {
			/* Probably Bus Reset */
			NCR5380_read(RESET_PARITY_INTERRUPT_REG);

886
			dsprintk(NDEBUG_INTR, instance, "unknown interrupt\n");
887 888 889
#ifdef SUN3_SCSI_VME
			dregs->csr |= CSR_DMA_ENABLE;
#endif
890 891 892
		}
		handled = 1;
	} else {
893
		dsprintk(NDEBUG_INTR, instance, "interrupt without IRQ bit\n");
894 895 896
#ifdef SUN3_SCSI_VME
		dregs->csr |= CSR_DMA_ENABLE;
#endif
897 898
	}

899
	spin_unlock_irqrestore(&hostdata->lock, flags);
900 901

	return IRQ_RETVAL(handled);
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902 903
}

904
/*
F
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905
 * Function : int NCR5380_select(struct Scsi_Host *instance,
906
 * struct scsi_cmnd *cmd)
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 *
 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
909 910
 * including ARBITRATION, SELECTION, and initial message out for
 * IDENTIFY and queue messages.
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 *
912
 * Inputs : instance - instantiation of the 5380 driver on which this
913
 * target lives, cmd - SCSI command to execute.
914
 *
915 916 917
 * 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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918
 *
919
 * Side effects :
920 921 922 923
 * 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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 *
925 926 927
 * 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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928
 *
929 930
 * 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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931
 */
932

933 934
static struct scsi_cmnd *NCR5380_select(struct Scsi_Host *instance,
                                        struct scsi_cmnd *cmd)
935
	__releases(&hostdata->lock) __acquires(&hostdata->lock)
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936
{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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938 939 940 941 942 943
	unsigned char tmp[3], phase;
	unsigned char *data;
	int len;
	int err;

	NCR5380_dprint(NDEBUG_ARBITRATION, instance);
944 945
	dsprintk(NDEBUG_ARBITRATION, instance, "starting arbitration, id = %d\n",
	         instance->this_id);
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947 948 949 950 951 952 953 954 955
	/*
	 * 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;

956 957
	/*
	 * 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);

963
	/*
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	 * Start arbitration.
	 */

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

970 971 972
	/* The chip now waits for BUS FREE phase. Then after the 800 ns
	 * Bus Free Delay, arbitration will begin.
	 */
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974
	spin_unlock_irq(&hostdata->lock);
975
	err = NCR5380_poll_politely2(hostdata, MODE_REG, MR_ARBITRATE, 0,
976 977
	                INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS,
	                                       ICR_ARBITRATION_PROGRESS, HZ);
978
	spin_lock_irq(&hostdata->lock);
979 980
	if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
		/* Reselection interrupt */
981
		goto out;
982
	}
983 984 985 986 987
	if (!hostdata->selecting) {
		/* Command was aborted */
		NCR5380_write(MODE_REG, MR_BASE);
		goto out;
	}
988 989 990 991
	if (err < 0) {
		NCR5380_write(MODE_REG, MR_BASE);
		shost_printk(KERN_ERR, instance,
		             "select: arbitration timeout\n");
992
		goto out;
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	}
994
	spin_unlock_irq(&hostdata->lock);
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996
	/* The SCSI-2 arbitration delay is 2.4 us */
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	udelay(3);

	/* Check for lost arbitration */
1000 1001 1002
	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);
1004
		dsprintk(NDEBUG_ARBITRATION, instance, "lost arbitration, deasserting MR_ARBITRATE\n");
1005
		spin_lock_irq(&hostdata->lock);
1006
		goto out;
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	}
1008 1009 1010 1011 1012 1013 1014

	/* 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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1016 1017
	/*
	 * 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)
	 */

1021 1022 1023 1024
	if (hostdata->flags & FLAG_TOSHIBA_DELAY)
		udelay(15);
	else
		udelay(2);
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1025

1026 1027
	spin_lock_irq(&hostdata->lock);

1028 1029
	/* NCR5380_reselect() clears MODE_REG after a reselection interrupt */
	if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE))
1030 1031 1032 1033 1034 1035 1036
		goto out;

	if (!hostdata->selecting) {
		NCR5380_write(MODE_REG, MR_BASE);
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		goto out;
	}
1037

1038
	dsprintk(NDEBUG_ARBITRATION, instance, "won arbitration\n");
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1039

1040 1041
	/*
	 * Now that we have won arbitration, start Selection process, asserting
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1042 1043 1044
	 * the host and target ID's on the SCSI bus.
	 */

1045
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask | (1 << scmd_id(cmd)));
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1046

1047
	/*
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1048 1049 1050 1051 1052
	 * 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.
	 */

1053 1054
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY |
	              ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL);
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1055 1056
	NCR5380_write(MODE_REG, MR_BASE);

1057
	/*
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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);

1063 1064
	spin_unlock_irq(&hostdata->lock);

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1065
	/*
1066
	 * The initiator shall then wait at least two deskew delays and release
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1067 1068
	 * the BSY signal.
	 */
1069
	udelay(1);        /* wingel -- wait two bus deskew delay >2*45ns */
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1070 1071

	/* Reset BSY */
1072 1073
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA |
	              ICR_ASSERT_ATN | ICR_ASSERT_SEL);
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1074

1075
	/*
L
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1076
	 * Something weird happens when we cease to drive BSY - looks
1077
	 * like the board/chip is letting us do another read before the
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1078 1079 1080 1081 1082
	 * 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
1083 1084 1085
	 * 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);

1094
	dsprintk(NDEBUG_SELECTION, instance, "selecting target %d\n", scmd_id(cmd));
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1095

1096 1097
	/*
	 * The SCSI specification calls for a 250 ms timeout for the actual
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1098 1099 1100
	 * selection.
	 */

1101
	err = NCR5380_poll_politely(hostdata, STATUS_REG, SR_BSY, SR_BSY,
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	                            msecs_to_jiffies(250));
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1103 1104

	if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1105
		spin_lock_irq(&hostdata->lock);
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1106 1107
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		NCR5380_reselect(instance);
1108 1109
		if (!hostdata->connected)
			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1110
		shost_printk(KERN_ERR, instance, "reselection after won arbitration?\n");
1111
		goto out;
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1112
	}
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1113 1114

	if (err < 0) {
1115
		spin_lock_irq(&hostdata->lock);
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1116 1117
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1118 1119 1120 1121 1122 1123 1124 1125
		/* 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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1126 1127
	}

1128 1129 1130
	/*
	 * 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);

	/*
1139
	 * Since we followed the SCSI spec, and raised ATN while SEL
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1140 1141 1142 1143 1144 1145 1146
	 * 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 */

1147
	err = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ);
1148
	spin_lock_irq(&hostdata->lock);
1149
	if (err < 0) {
1150 1151
		shost_printk(KERN_ERR, instance, "select: REQ timeout\n");
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
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1152
		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1153 1154 1155 1156 1157
		goto out;
	}
	if (!hostdata->selecting) {
		do_abort(instance);
		goto out;
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1158 1159
	}

1160 1161
	dsprintk(NDEBUG_SELECTION, instance, "target %d selected, going into MESSAGE OUT phase.\n",
	         scmd_id(cmd));
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1162
	tmp[0] = IDENTIFY(((instance->irq == NO_IRQ) ? 0 : 1), cmd->device->lun);
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1163 1164 1165 1166 1167

	len = 1;
	data = tmp;
	phase = PHASE_MSGOUT;
	NCR5380_transfer_pio(instance, &phase, &len, &data);
1168 1169 1170 1171 1172 1173 1174 1175 1176
	if (len) {
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		cmd->result = DID_ERROR << 16;
		complete_cmd(instance, cmd);
		dsprintk(NDEBUG_SELECTION, instance, "IDENTIFY message transfer failed\n");
		cmd = NULL;
		goto out;
	}

1177
	dsprintk(NDEBUG_SELECTION, instance, "nexus established.\n");
1178

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1179
	hostdata->connected = cmd;
1180
	hostdata->busy[cmd->device->id] |= 1 << cmd->device->lun;
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1181

1182 1183 1184 1185
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif

1186
	initialize_SCp(cmd);
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1187

1188 1189 1190 1191 1192 1193 1194
	cmd = NULL;

out:
	if (!hostdata->selecting)
		return NULL;
	hostdata->selecting = NULL;
	return cmd;
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1195 1196
}

1197 1198
/*
 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1199
 * unsigned char *phase, int *count, unsigned char **data)
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1200 1201 1202
 *
 * Purpose : transfers data in given phase using polled I/O
 *
1203
 * Inputs : instance - instance of driver, *phase - pointer to
1204 1205
 * what phase is expected, *count - pointer to number of
 * bytes to transfer, **data - pointer to data pointer.
1206
 *
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 * Returns : -1 when different phase is entered without transferring
1208
 * maximum number of bytes, 0 if all bytes are transferred or exit
1209
 * is in same phase.
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1210
 *
1211
 * Also, *phase, *count, *data are modified in place.
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1212 1213 1214 1215 1216
 *
 * XXX Note : handling for bus free may be useful.
 */

/*
1217
 * 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.
 */

1222 1223 1224 1225
static int NCR5380_transfer_pio(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
{
1226
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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	unsigned char p = *phase, tmp;
	int c = *count;
	unsigned char *d = *data;

1231 1232
	/*
	 * The NCR5380 chip will only drive the SCSI bus when the
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1233 1234 1235 1236
	 * phase specified in the appropriate bits of the TARGET COMMAND
	 * REGISTER match the STATUS REGISTER
	 */

1237
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
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1238 1239

	do {
1240 1241 1242
		/*
		 * Wait for assertion of REQ, after which the phase bits will be
		 * valid
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1243 1244
		 */

1245
		if (NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ) < 0)
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1246 1247
			break;

1248
		dsprintk(NDEBUG_HANDSHAKE, instance, "REQ asserted\n");
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1249 1250

		/* Check for phase mismatch */
1251
		if ((NCR5380_read(STATUS_REG) & PHASE_MASK) != p) {
1252 1253
			dsprintk(NDEBUG_PIO, instance, "phase mismatch\n");
			NCR5380_dprint_phase(NDEBUG_PIO, instance);
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1254 1255
			break;
		}
1256

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1257 1258 1259 1260 1261 1262 1263 1264
		/* 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;

1265
		/*
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1266 1267 1268 1269 1270 1271 1272 1273 1274 1275
		 * 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);
1276 1277
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ACK);
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1278
			} else {
1279 1280
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ATN);
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1281
				NCR5380_dprint(NDEBUG_PIO, instance);
1282 1283
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
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1284 1285 1286 1287 1288 1289
			}
		} else {
			NCR5380_dprint(NDEBUG_PIO, instance);
			NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
		}

1290
		if (NCR5380_poll_politely(hostdata,
1291 1292 1293
		                          STATUS_REG, SR_REQ, 0, 5 * HZ) < 0)
			break;

1294
		dsprintk(NDEBUG_HANDSHAKE, instance, "REQ negated, handshake complete\n");
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1295 1296

/*
1297 1298
 * 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
1299
 * message.  ATN must be dropped as ACK is dropped.
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1300
 *
1301
 * 2.  We are in a MSGIN phase, and we are on the last byte of the
1302 1303
 * 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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 *
 * 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);

1315
	dsprintk(NDEBUG_PIO, instance, "residual %d\n", c);
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1316 1317 1318 1319

	*count = c;
	*data = d;
	tmp = NCR5380_read(STATUS_REG);
1320 1321 1322 1323 1324
	/* 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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1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335
		*phase = tmp & PHASE_MASK;
	else
		*phase = PHASE_UNKNOWN;

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

/**
1336 1337
 * do_reset - issue a reset command
 * @instance: adapter to reset
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1338
 *
1339 1340
 * Issue a reset sequence to the NCR5380 and try and get the bus
 * back into sane shape.
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1341
 *
1342 1343 1344
 * 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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1345
 */
1346

1347 1348
static void do_reset(struct Scsi_Host *instance)
{
1349
	struct NCR5380_hostdata __maybe_unused *hostdata = shost_priv(instance);
1350 1351 1352 1353 1354
	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);
1356
	udelay(50);
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1357
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1358 1359
	(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
	local_irq_restore(flags);
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1360 1361
}

1362 1363 1364 1365
/**
 * 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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1366
 *
1367
 * Returns 0 on success, -1 on failure.
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1368 1369
 */

1370 1371
static int do_abort(struct Scsi_Host *instance)
{
1372
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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1373 1374 1375 1376 1377 1378 1379
	unsigned char *msgptr, phase, tmp;
	int len;
	int rc;

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

1380 1381 1382 1383
	/*
	 * 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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1384
	 * other phase and will have to source/sink data.
1385
	 *
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1386 1387 1388 1389
	 * We really don't care what value was on the bus or what value
	 * the target sees, so we just handshake.
	 */

1390
	rc = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, 10 * HZ);
1391
	if (rc < 0)
1392
		goto timeout;
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1393

1394
	tmp = NCR5380_read(STATUS_REG) & PHASE_MASK;
1395

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1396 1397
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

1398
	if (tmp != PHASE_MSGOUT) {
1399 1400
		NCR5380_write(INITIATOR_COMMAND_REG,
		              ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1401
		rc = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, 0, 3 * HZ);
1402
		if (rc < 0)
1403 1404
			goto timeout;
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
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1405
	}
1406

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1407 1408 1409 1410
	tmp = ABORT;
	msgptr = &tmp;
	len = 1;
	phase = PHASE_MSGOUT;
1411
	NCR5380_transfer_pio(instance, &phase, &len, &msgptr);
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1412 1413 1414 1415 1416 1417 1418

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

	return len ? -1 : 0;
1419 1420 1421 1422

timeout:
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
	return -1;
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1423 1424
}

1425 1426
/*
 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1427
 * unsigned char *phase, int *count, unsigned char **data)
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1428 1429
 *
 * Purpose : transfers data in given phase using either real
1430
 * or pseudo DMA.
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1431
 *
1432
 * Inputs : instance - instance of driver, *phase - pointer to
1433 1434
 * what phase is expected, *count - pointer to number of
 * bytes to transfer, **data - pointer to data pointer.
1435
 *
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1436
 * Returns : -1 when different phase is entered without transferring
1437 1438
 * maximum number of bytes, 0 if all bytes or transferred or exit
 * is in same phase.
L
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1439
 *
1440
 * Also, *phase, *count, *data are modified in place.
L
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1441 1442 1443
 */


1444 1445 1446 1447 1448
static int NCR5380_transfer_dma(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
1449 1450 1451
	int c = *count;
	unsigned char p = *phase;
	unsigned char *d = *data;
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1452
	unsigned char tmp;
1453
	int result = 0;
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1454 1455 1456 1457 1458 1459

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

1460
	hostdata->connected->SCp.phase = p;
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1461

1462 1463 1464 1465 1466 1467
	if (p & SR_IO) {
		if (hostdata->read_overruns)
			c -= hostdata->read_overruns;
		else if (hostdata->flags & FLAG_DMA_FIXUP)
			--c;
	}
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1468

1469 1470
	dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n",
	         (p & SR_IO) ? "receive" : "send", c, d);
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1471

1472 1473 1474 1475 1476
#ifdef CONFIG_SUN3
	/* send start chain */
	sun3scsi_dma_start(c, *data);
#endif

1477 1478 1479 1480 1481 1482 1483 1484 1485
	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)
1486
			result = NCR5380_dma_recv_setup(hostdata, d, c);
1487
		else
1488
			result = NCR5380_dma_send_setup(hostdata, d, c);
1489
	}
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1490

1491
	/*
1492 1493
	 * On the PAS16 at least I/O recovery delays are not needed here.
	 * Everyone else seems to want them.
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1494 1495 1496
	 */

	if (p & SR_IO) {
1497
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1498
		NCR5380_io_delay(1);
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1499 1500
		NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
	} else {
1501
		NCR5380_io_delay(1);
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1502
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1503
		NCR5380_io_delay(1);
L
Linus Torvalds 已提交
1504
		NCR5380_write(START_DMA_SEND_REG, 0);
1505
		NCR5380_io_delay(1);
L
Linus Torvalds 已提交
1506 1507
	}

1508 1509 1510 1511 1512 1513 1514
#ifdef CONFIG_SUN3
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_DMA_ENABLE;
#endif
	sun3_dma_active = 1;
#endif

1515 1516 1517 1518 1519
	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)
1520
			result = NCR5380_dma_recv_setup(hostdata, d, c);
1521
		else
1522
			result = NCR5380_dma_send_setup(hostdata, d, c);
1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537
	}

	/* 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
Linus Torvalds 已提交
1538
/*
1539
 * A note regarding the DMA errata workarounds for early NMOS silicon.
F
Finn Thain 已提交
1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565
 *
 * 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
1566
 * problem.  The chosen fix is to DMA fewer bytes, then check for the
F
Finn Thain 已提交
1567 1568 1569
 * 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
1570 1571
 */

1572 1573
	if (hostdata->flags & FLAG_DMA_FIXUP) {
		if (p & SR_IO) {
L
Linus Torvalds 已提交
1574
			/*
1575
			 * The workaround was to transfer fewer bytes than we
1576
			 * intended to with the pseudo-DMA read function, wait for
L
Linus Torvalds 已提交
1577 1578
			 * the chip to latch the last byte, read it, and then disable
			 * pseudo-DMA mode.
1579
			 *
L
Linus Torvalds 已提交
1580 1581 1582 1583
			 * 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
1584 1585
			 * 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
1586 1587 1588
			 * byte.
			 */

1589
			if (NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
1590
			                          BASR_DRQ, BASR_DRQ, HZ) < 0) {
1591
				result = -1;
1592 1593
				shost_printk(KERN_ERR, instance, "PDMA read: DRQ timeout\n");
			}
1594
			if (NCR5380_poll_politely(hostdata, STATUS_REG,
1595
			                          SR_REQ, 0, HZ) < 0) {
1596
				result = -1;
1597
				shost_printk(KERN_ERR, instance, "PDMA read: !REQ timeout\n");
L
Linus Torvalds 已提交
1598
			}
1599 1600
			d[*count - 1] = NCR5380_read(INPUT_DATA_REG);
		} else {
L
Linus Torvalds 已提交
1601
			/*
1602 1603
			 * 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
1604
			 */
1605
			if (NCR5380_poll_politely2(hostdata,
1606 1607
			     BUS_AND_STATUS_REG, BASR_DRQ, BASR_DRQ,
			     BUS_AND_STATUS_REG, BASR_PHASE_MATCH, 0, HZ) < 0) {
1608
				result = -1;
1609
				shost_printk(KERN_ERR, instance, "PDMA write: DRQ and phase timeout\n");
L
Linus Torvalds 已提交
1610 1611 1612
			}
		}
	}
1613 1614

	NCR5380_dma_complete(instance);
1615
	return result;
L
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1616 1617 1618 1619 1620
}

/*
 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
 *
1621
 * Purpose : run through the various SCSI phases and do as the target
1622 1623
 * directs us to.  Operates on the currently connected command,
 * instance->connected.
L
Linus Torvalds 已提交
1624 1625 1626
 *
 * Inputs : instance, instance for which we are doing commands
 *
1627
 * Side effects : SCSI things happen, the disconnected queue will be
1628 1629
 * modified if a command disconnects, *instance->connected will
 * change.
L
Linus Torvalds 已提交
1630
 *
1631
 * XXX Note : we need to watch for bus free or a reset condition here
1632
 * to recover from an unexpected bus free condition.
L
Linus Torvalds 已提交
1633 1634
 */

1635
static void NCR5380_information_transfer(struct Scsi_Host *instance)
1636
	__releases(&hostdata->lock) __acquires(&hostdata->lock)
1637
{
F
Finn Thain 已提交
1638
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
L
Linus Torvalds 已提交
1639 1640 1641 1642 1643 1644
	unsigned char msgout = NOP;
	int sink = 0;
	int len;
	int transfersize;
	unsigned char *data;
	unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
1645
	struct scsi_cmnd *cmd;
L
Linus Torvalds 已提交
1646

1647 1648 1649 1650
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif

1651
	while ((cmd = hostdata->connected)) {
1652 1653
		struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);

L
Linus Torvalds 已提交
1654 1655 1656 1657 1658 1659 1660 1661
		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);
			}
1662
#ifdef CONFIG_SUN3
1663 1664 1665
			if (phase == PHASE_CMDOUT &&
			    sun3_dma_setup_done != cmd) {
				int count;
1666 1667

				if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
1668 1669 1670 1671
					++cmd->SCp.buffer;
					--cmd->SCp.buffers_residual;
					cmd->SCp.this_residual = cmd->SCp.buffer->length;
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
1672 1673
				}

1674 1675 1676 1677 1678 1679 1680 1681 1682
				count = sun3scsi_dma_xfer_len(hostdata, cmd);

				if (count > 0) {
					if (rq_data_dir(cmd->request))
						sun3scsi_dma_send_setup(hostdata,
						                        cmd->SCp.ptr, count);
					else
						sun3scsi_dma_recv_setup(hostdata,
						                        cmd->SCp.ptr, count);
1683 1684 1685 1686 1687 1688 1689 1690
					sun3_dma_setup_done = cmd;
				}
#ifdef SUN3_SCSI_VME
				dregs->csr |= CSR_INTR;
#endif
			}
#endif /* CONFIG_SUN3 */

L
Linus Torvalds 已提交
1691 1692 1693
			if (sink && (phase != PHASE_MSGOUT)) {
				NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

1694 1695
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
				              ICR_ASSERT_ACK);
1696 1697
				while (NCR5380_read(STATUS_REG) & SR_REQ)
					;
1698 1699
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_ATN);
L
Linus Torvalds 已提交
1700 1701 1702
				sink = 0;
				continue;
			}
1703

L
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1704 1705 1706
			switch (phase) {
			case PHASE_DATAOUT:
#if (NDEBUG & NDEBUG_NO_DATAOUT)
1707
				shost_printk(KERN_DEBUG, instance, "NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n");
L
Linus Torvalds 已提交
1708 1709 1710
				sink = 1;
				do_abort(instance);
				cmd->result = DID_ERROR << 16;
1711
				complete_cmd(instance, cmd);
F
Finn Thain 已提交
1712
				hostdata->connected = NULL;
L
Linus Torvalds 已提交
1713 1714
				return;
#endif
F
Finn Thain 已提交
1715
			case PHASE_DATAIN:
1716
				/*
L
Linus Torvalds 已提交
1717 1718 1719 1720 1721 1722 1723 1724
				 * 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
1725
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
1726 1727 1728
					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
1729
				}
1730

L
Linus Torvalds 已提交
1731
				/*
1732
				 * The preferred transfer method is going to be
L
Linus Torvalds 已提交
1733 1734 1735 1736 1737 1738 1739 1740
				 * 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.
				 */

1741
				transfersize = 0;
1742
				if (!cmd->device->borken)
1743
					transfersize = NCR5380_dma_xfer_len(hostdata, cmd);
1744

1745
				if (transfersize > 0) {
L
Linus Torvalds 已提交
1746
					len = transfersize;
1747 1748
					if (NCR5380_transfer_dma(instance, &phase,
					    &len, (unsigned char **)&cmd->SCp.ptr)) {
L
Linus Torvalds 已提交
1749
						/*
1750 1751 1752
						 * If the watchdog timer fires, all future
						 * accesses to this device will use the
						 * polled-IO.
L
Linus Torvalds 已提交
1753
						 */
J
Jeff Garzik 已提交
1754
						scmd_printk(KERN_INFO, cmd,
1755
							"switching to slow handshake\n");
L
Linus Torvalds 已提交
1756 1757 1758 1759 1760
						cmd->device->borken = 1;
						sink = 1;
						do_abort(instance);
						cmd->result = DID_ERROR << 16;
						/* XXX - need to source or sink data here, as appropriate */
1761
					}
F
Finn Thain 已提交
1762
				} else {
1763 1764
					/* Transfer a small chunk so that the
					 * irq mode lock is not held too long.
1765
					 */
1766 1767
					transfersize = min(cmd->SCp.this_residual,
							   NCR5380_PIO_CHUNK_SIZE);
1768 1769
					len = transfersize;
					NCR5380_transfer_pio(instance, &phase, &len,
1770
					                     (unsigned char **)&cmd->SCp.ptr);
1771
					cmd->SCp.this_residual -= transfersize - len;
1772
				}
1773 1774 1775 1776
#ifdef CONFIG_SUN3
				if (sun3_dma_setup_done == cmd)
					sun3_dma_setup_done = NULL;
#endif
1777
				return;
L
Linus Torvalds 已提交
1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789
			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);
1790 1791 1792 1793
					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
1794 1795
					hostdata->connected = NULL;

F
Finn Thain 已提交
1796 1797 1798
					cmd->result &= ~0xffff;
					cmd->result |= cmd->SCp.Status;
					cmd->result |= cmd->SCp.Message << 8;
1799

F
Finn Thain 已提交
1800
					if (cmd->cmnd[0] == REQUEST_SENSE)
1801
						complete_cmd(instance, cmd);
F
Finn Thain 已提交
1802 1803 1804 1805 1806 1807 1808 1809 1810
					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
1811 1812
					}

1813 1814
					/*
					 * Restore phase bits to 0 so an interrupted selection,
L
Linus Torvalds 已提交
1815 1816 1817
					 * arbitration can resume.
					 */
					NCR5380_write(TARGET_COMMAND_REG, 0);
1818 1819 1820

					/* Enable reselect interrupts */
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1821 1822

					maybe_release_dma_irq(instance);
L
Linus Torvalds 已提交
1823 1824 1825 1826 1827 1828 1829 1830 1831
					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
1832
						hostdata->busy[cmd->device->id] |= (1 << (cmd->device->lun & 0xFF));
L
Linus Torvalds 已提交
1833 1834 1835 1836
						break;
					default:
						break;
					}
1837
					break;
1838 1839 1840 1841 1842 1843 1844 1845
				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);
1846

1847 1848 1849 1850 1851
					/*
					 * Restore phase bits to 0 so an interrupted selection,
					 * arbitration can resume.
					 */
					NCR5380_write(TARGET_COMMAND_REG, 0);
L
Linus Torvalds 已提交
1852

1853 1854
					/* Enable reselect interrupts */
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1855 1856 1857
#ifdef SUN3_SCSI_VME
					dregs->csr |= CSR_DMA_ENABLE;
#endif
1858
					return;
1859
					/*
L
Linus Torvalds 已提交
1860
					 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
1861
					 * operation, in violation of the SCSI spec so we can safely
L
Linus Torvalds 已提交
1862 1863
					 * ignore SAVE/RESTORE pointers calls.
					 *
1864
					 * Unfortunately, some disks violate the SCSI spec and
L
Linus Torvalds 已提交
1865
					 * don't issue the required SAVE_POINTERS message before
1866
					 * disconnecting, and we have to break spec to remain
L
Linus Torvalds 已提交
1867 1868 1869 1870 1871 1872 1873 1874
					 * 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
1875 1876 1877 1878
					/*
					 * Start the message buffer with the EXTENDED_MESSAGE
					 * byte, since spi_print_msg() wants the whole thing.
					 */
L
Linus Torvalds 已提交
1879 1880 1881
					extended_msg[0] = EXTENDED_MESSAGE;
					/* Accept first byte by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1882 1883 1884

					spin_unlock_irq(&hostdata->lock);

1885
					dsprintk(NDEBUG_EXTENDED, instance, "receiving extended message\n");
L
Linus Torvalds 已提交
1886 1887 1888 1889 1890

					len = 2;
					data = extended_msg + 1;
					phase = PHASE_MSGIN;
					NCR5380_transfer_pio(instance, &phase, &len, &data);
1891 1892 1893
					dsprintk(NDEBUG_EXTENDED, instance, "length %d, code 0x%02x\n",
					         (int)extended_msg[1],
					         (int)extended_msg[2]);
L
Linus Torvalds 已提交
1894

1895 1896
					if (!len && extended_msg[1] > 0 &&
					    extended_msg[1] <= sizeof(extended_msg) - 2) {
L
Linus Torvalds 已提交
1897 1898 1899 1900 1901 1902 1903
						/* 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);
1904 1905
						dsprintk(NDEBUG_EXTENDED, instance, "message received, residual %d\n",
						         len);
L
Linus Torvalds 已提交
1906 1907 1908 1909 1910 1911 1912 1913 1914

						switch (extended_msg[2]) {
						case EXTENDED_SDTR:
						case EXTENDED_WDTR:
						case EXTENDED_MODIFY_DATA_POINTER:
						case EXTENDED_EXTENDED_IDENTIFY:
							tmp = 0;
						}
					} else if (len) {
1915
						shost_printk(KERN_ERR, instance, "error receiving extended message\n");
L
Linus Torvalds 已提交
1916 1917
						tmp = 0;
					} else {
1918 1919
						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
1920 1921
						tmp = 0;
					}
1922 1923 1924 1925 1926

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

L
Linus Torvalds 已提交
1927 1928
					/* Fall through to reject message */

1929 1930
					/*
					 * If we get something weird that we aren't expecting,
L
Linus Torvalds 已提交
1931 1932 1933 1934
					 * reject it.
					 */
				default:
					if (!tmp) {
1935
						shost_printk(KERN_ERR, instance, "rejecting message ");
1936
						spi_print_msg(extended_msg);
L
Linus Torvalds 已提交
1937 1938
						printk("\n");
					} else if (tmp != EXTENDED_MESSAGE)
J
Jeff Garzik 已提交
1939
						scmd_printk(KERN_INFO, cmd,
1940 1941
						            "rejecting unknown message %02x\n",
						            tmp);
L
Linus Torvalds 已提交
1942
					else
J
Jeff Garzik 已提交
1943
						scmd_printk(KERN_INFO, cmd,
1944 1945
						            "rejecting unknown extended message code %02x, length %d\n",
						            extended_msg[1], extended_msg[0]);
L
Linus Torvalds 已提交
1946 1947 1948 1949

					msgout = MESSAGE_REJECT;
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
					break;
1950
				} /* switch (tmp) */
L
Linus Torvalds 已提交
1951 1952 1953 1954 1955 1956 1957 1958 1959
				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;
1960
					complete_cmd(instance, cmd);
1961
					maybe_release_dma_irq(instance);
L
Linus Torvalds 已提交
1962 1963 1964 1965 1966 1967 1968 1969
					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
					return;
				}
				msgout = NOP;
				break;
			case PHASE_CMDOUT:
				len = cmd->cmd_len;
				data = cmd->cmnd;
1970 1971 1972 1973
				/*
				 * 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
1974 1975 1976 1977 1978 1979 1980 1981 1982 1983
				 */
				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:
1984
				shost_printk(KERN_ERR, instance, "unknown phase\n");
1985
				NCR5380_dprint(NDEBUG_ANY, instance);
1986
			} /* switch(phase) */
1987
		} else {
1988
			spin_unlock_irq(&hostdata->lock);
1989
			NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ);
1990
			spin_lock_irq(&hostdata->lock);
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1991
		}
1992
	}
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1993 1994 1995 1996 1997
}

/*
 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
 *
1998
 * Purpose : does reselection, initializing the instance->connected
1999 2000
 * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
 * nexus has been reestablished,
2001
 *
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2002 2003 2004
 * Inputs : instance - this instance of the NCR5380.
 */

2005 2006
static void NCR5380_reselect(struct Scsi_Host *instance)
{
F
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2007
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
L
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2008
	unsigned char target_mask;
2009
	unsigned char lun;
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2010
	unsigned char msg[3];
2011 2012
	struct NCR5380_cmd *ncmd;
	struct scsi_cmnd *tmp;
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2013 2014 2015 2016 2017 2018 2019 2020 2021

	/*
	 * 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);
2022 2023

	dsprintk(NDEBUG_RESELECTION, instance, "reselect\n");
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2024

2025
	/*
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2026 2027 2028 2029 2030 2031 2032 2033 2034
	 * 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);
2035
	if (NCR5380_poll_politely(hostdata,
2036 2037 2038 2039
	                          STATUS_REG, SR_SEL, 0, 2 * HZ) < 0) {
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		return;
	}
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2040 2041 2042 2043 2044 2045
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

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

2046
	if (NCR5380_poll_politely(hostdata,
2047 2048 2049 2050
	                          STATUS_REG, SR_REQ, SR_REQ, 2 * HZ) < 0) {
		do_abort(instance);
		return;
	}
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2051

2052 2053 2054
#ifdef CONFIG_SUN3
	/* acknowledge toggle to MSGIN */
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN));
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2055

2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069
	/* 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;
		}
2070
	}
2071
#endif /* CONFIG_SUN3 */
2072

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2073
	if (!(msg[0] & 0x80)) {
2074
		shost_printk(KERN_ERR, instance, "expecting IDENTIFY message, got ");
2075
		spi_print_msg(msg);
2076 2077 2078 2079 2080
		printk("\n");
		do_abort(instance);
		return;
	}
	lun = msg[0] & 0x07;
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2081

2082 2083 2084 2085 2086
	/*
	 * 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.
	 */
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2087

2088 2089 2090 2091
	/*
	 * 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.
	 */
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2092

2093 2094 2095 2096 2097 2098 2099 2100
	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;
2101
			break;
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2102 2103
		}
	}
2104 2105 2106 2107 2108

	if (tmp) {
		dsprintk(NDEBUG_RESELECTION | NDEBUG_QUEUES, instance,
		         "reselect: removed %p from disconnected queue\n", tmp);
	} else {
2109 2110 2111
		shost_printk(KERN_ERR, instance, "target bitmask 0x%02x lun %d not in disconnected queue.\n",
		             target_mask, lun);
		/*
2112 2113
		 * Since we have an established nexus that we can't do anything
		 * with, we must abort it.
2114
		 */
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2115
		do_abort(instance);
2116
		return;
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2117
	}
2118

2119
#ifdef CONFIG_SUN3
2120 2121
	if (sun3_dma_setup_done != tmp) {
		int count;
2122 2123

		if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
2124 2125 2126 2127
			++tmp->SCp.buffer;
			--tmp->SCp.buffers_residual;
			tmp->SCp.this_residual = tmp->SCp.buffer->length;
			tmp->SCp.ptr = sg_virt(tmp->SCp.buffer);
2128 2129
		}

2130 2131 2132 2133 2134 2135 2136 2137 2138
		count = sun3scsi_dma_xfer_len(hostdata, tmp);

		if (count > 0) {
			if (rq_data_dir(tmp->request))
				sun3scsi_dma_send_setup(hostdata,
				                        tmp->SCp.ptr, count);
			else
				sun3scsi_dma_recv_setup(hostdata,
				                        tmp->SCp.ptr, count);
2139 2140 2141 2142 2143 2144 2145
			sun3_dma_setup_done = tmp;
		}
	}

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

2146 2147 2148 2149
	/* Accept message by clearing ACK */
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	hostdata->connected = tmp;
2150 2151
	dsprintk(NDEBUG_RESELECTION, instance, "nexus established, target %d, lun %llu\n",
	         scmd_id(tmp), tmp->device->lun);
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2152 2153
}

2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206
/**
 * 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.
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2207
 *
2208
 * If the command has not completed yet, we must not fail to find it.
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2209 2210 2211 2212
 * 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.
2213 2214 2215
 *
 * The lock protects driver data structures, but EH handlers also use it
 * to serialize their own execution and prevent their own re-entry.
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2216 2217
 */

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2218 2219
static int NCR5380_abort(struct scsi_cmnd *cmd)
{
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2220
	struct Scsi_Host *instance = cmd->device->host;
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2221
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
2222
	unsigned long flags;
2223
	int result = SUCCESS;
2224

2225 2226
	spin_lock_irqsave(&hostdata->lock, flags);

2227
#if (NDEBUG & NDEBUG_ANY)
2228
	scmd_printk(KERN_INFO, cmd, __func__);
2229
#endif
2230 2231
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
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2232

2233 2234 2235 2236 2237
	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 */
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2238
		goto out;
2239 2240
	}

2241 2242 2243 2244 2245 2246 2247 2248 2249
	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;
	}

2250 2251 2252
	if (list_del_cmd(&hostdata->disconnected, cmd)) {
		dsprintk(NDEBUG_ABORT, instance,
		         "abort: removed %p from disconnected list\n", cmd);
2253 2254 2255
		/* Can't call NCR5380_select() and send ABORT because that
		 * means releasing the lock. Need a bus reset.
		 */
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2256 2257
		set_host_byte(cmd, DID_ERROR);
		complete_cmd(instance, cmd);
2258 2259
		result = FAILED;
		goto out;
2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272
	}

	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);
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Finn Thain 已提交
2273 2274 2275 2276 2277 2278 2279 2280
		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);
2281 2282 2283 2284 2285 2286 2287 2288 2289 2290
		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);
2291
	maybe_release_dma_irq(instance);
2292
	spin_unlock_irqrestore(&hostdata->lock, flags);
2293

2294
	return result;
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2295 2296 2297
}


2298
/**
2299
 * NCR5380_host_reset - reset the SCSI host
2300
 * @cmd: SCSI command undergoing EH
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2301
 *
2302
 * Returns SUCCESS
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2303 2304
 */

2305
static int NCR5380_host_reset(struct scsi_cmnd *cmd)
2306 2307
{
	struct Scsi_Host *instance = cmd->device->host;
2308
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
2309
	int i;
2310
	unsigned long flags;
2311
	struct NCR5380_cmd *ncmd;
2312

2313
	spin_lock_irqsave(&hostdata->lock, flags);
2314 2315

#if (NDEBUG & NDEBUG_ANY)
2316
	scmd_printk(KERN_INFO, cmd, __func__);
2317
#endif
2318 2319
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
2320 2321

	do_reset(instance);
2322

2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333
	/* 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!
	 */

2334 2335 2336 2337 2338 2339 2340 2341 2342 2343
	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;
	}
2344 2345 2346 2347 2348

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

		set_host_byte(cmd, DID_RESET);
2349
		complete_cmd(instance, cmd);
2350
	}
2351
	INIT_LIST_HEAD(&hostdata->disconnected);
2352 2353 2354 2355 2356 2357 2358

	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);
	}
2359
	INIT_LIST_HEAD(&hostdata->autosense);
2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371

	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);
2372
	maybe_release_dma_irq(instance);
2373
	spin_unlock_irqrestore(&hostdata->lock, flags);
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2374 2375 2376

	return SUCCESS;
}