NCR5380.c 70.2 KB
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// SPDX-License-Identifier: GPL-2.0
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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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static void bus_reset_cleanup(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 */
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		if (status_byte(cmd->result) != GOOD) {
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			scsi_eh_restore_cmnd(cmd, &hostdata->ses);
519
		} else {
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			scsi_eh_restore_cmnd(cmd, &hostdata->ses);
521 522
			set_driver_byte(cmd, DRIVER_SENSE);
		}
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		hostdata->sensing = NULL;
	}

526 527 528
	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);
543
	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:
550
		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;
	}
555
#endif /* (NDEBUG & NDEBUG_NO_WRITE) */
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	cmd->result = 0;

559 560 561
	if (!NCR5380_acquire_dma_irq(instance))
		return SCSI_MLQUEUE_HOST_BUSY;

562
	spin_lock_irqsave(&hostdata->lock, flags);
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564 565
	/*
	 * 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
567
	 * 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.
	 */

571 572 573 574 575
	if (cmd->cmnd[0] == REQUEST_SENSE)
		list_add(&ncmd->list, &hostdata->unissued);
	else
		list_add_tail(&ncmd->list, &hostdata->unissued);

576
	spin_unlock_irqrestore(&hostdata->lock, flags);
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578 579
	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 */
582
	queue_work(hostdata->work_q, &hostdata->main_task);
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	return 0;
}

586 587 588 589 590 591 592 593 594
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 &&
595
	    !hostdata->selecting) {
596
		NCR5380_release_dma_irq(instance);
597
	}
598 599
}

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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;

617
	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);

650
	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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/**
659
 * NCR5380_main - NCR state machines
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 *
661 662 663 664
 * 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 =
670
		container_of(work, struct NCR5380_hostdata, main_task);
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	struct Scsi_Host *instance = hostdata->host;
	int done;
673

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	do {
		done = 1;
676

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		spin_lock_irq(&hostdata->lock);
678 679 680 681 682
		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);
685

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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.
			 */
698

699
			if (!NCR5380_select(instance, cmd)) {
700
				dsprintk(NDEBUG_MAIN, instance, "main: select complete\n");
701
				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);
			}
		}
708
		if (hostdata->connected && !hostdata->dma_len) {
709
			dsprintk(NDEBUG_MAIN, instance, "main: performing information transfer\n");
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			NCR5380_information_transfer(instance);
			done = 0;
712
		}
713 714
		if (!hostdata->connected)
			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
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		spin_unlock_irq(&hostdata->lock);
		if (!done)
			cond_resched();
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	} while (!done);
}

721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751
/*
 * 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");
			}
		}
	}

752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768
#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

769 770 771 772
	NCR5380_write(MODE_REG, MR_BASE);
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
	NCR5380_read(RESET_PARITY_INTERRUPT_REG);

773
	transferred = hostdata->dma_len - NCR5380_dma_residual(hostdata);
774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803
	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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/**
805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835
 * 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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 */

838
static irqreturn_t __maybe_unused NCR5380_intr(int irq, void *dev_id)
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{
840
	struct Scsi_Host *instance = dev_id;
841 842
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	int handled = 0;
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	unsigned char basr;
	unsigned long flags;

846
	spin_lock_irqsave(&hostdata->lock, flags);
847 848 849 850 851 852

	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);

853 854
		dsprintk(NDEBUG_INTR, instance, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n",
		         irq, basr, sr, mr);
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856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871
		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) &&
872 873 874 875 876
		    (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);

877
			dsprintk(NDEBUG_INTR, instance, "interrupt with SEL and IO\n");
878 879 880 881

			if (!hostdata->connected) {
				NCR5380_reselect(instance);
				queue_work(hostdata->work_q, &hostdata->main_task);
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882
			}
883 884 885 886 887 888
			if (!hostdata->connected)
				NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
		} else {
			/* Probably Bus Reset */
			NCR5380_read(RESET_PARITY_INTERRUPT_REG);

F
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889 890 891 892 893 894 895 896
			if (sr & SR_RST) {
				/* Certainly Bus Reset */
				shost_printk(KERN_WARNING, instance,
					     "bus reset interrupt\n");
				bus_reset_cleanup(instance);
			} else {
				dsprintk(NDEBUG_INTR, instance, "unknown interrupt\n");
			}
897 898 899
#ifdef SUN3_SCSI_VME
			dregs->csr |= CSR_DMA_ENABLE;
#endif
900 901 902
		}
		handled = 1;
	} else {
903
		dsprintk(NDEBUG_INTR, instance, "interrupt without IRQ bit\n");
904 905 906
#ifdef SUN3_SCSI_VME
		dregs->csr |= CSR_DMA_ENABLE;
#endif
907 908
	}

909
	spin_unlock_irqrestore(&hostdata->lock, flags);
910 911

	return IRQ_RETVAL(handled);
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}

914 915 916 917
/**
 * NCR5380_select - attempt arbitration and selection for a given command
 * @instance: the Scsi_Host instance
 * @cmd: the scsi_cmnd to execute
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918
 *
919 920
 * This routine establishes an I_T_L nexus for a SCSI command. This involves
 * ARBITRATION, SELECTION and MESSAGE OUT phases and an IDENTIFY message.
921
 *
922 923
 * Returns true if the operation should be retried.
 * Returns false if it should not be retried.
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924
 *
925
 * Side effects :
926 927 928 929
 * 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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 *
931 932
 * If successful : the I_T_L nexus will be established, and
 * hostdata->connected will be set to cmd.
933
 * SELECT interrupt will be disabled.
L
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934
 *
935 936
 * 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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937
 */
938

939
static bool NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
940
	__releases(&hostdata->lock) __acquires(&hostdata->lock)
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941
{
F
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942
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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943 944 945 946
	unsigned char tmp[3], phase;
	unsigned char *data;
	int len;
	int err;
947
	bool ret = true;
948 949
	bool can_disconnect = instance->irq != NO_IRQ &&
			      cmd->cmnd[0] != REQUEST_SENSE;
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	NCR5380_dprint(NDEBUG_ARBITRATION, instance);
952 953
	dsprintk(NDEBUG_ARBITRATION, instance, "starting arbitration, id = %d\n",
	         instance->this_id);
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955 956 957
	/*
	 * Arbitration and selection phases are slow and involve dropping the
	 * lock, so we have to watch out for EH. An exception handler may
958
	 * change 'selecting' to NULL. This function will then return false
959 960 961 962 963
	 * so that the caller will forget about 'cmd'. (During information
	 * transfer phases, EH may change 'connected' to NULL.)
	 */
	hostdata->selecting = cmd;

964 965
	/*
	 * 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);

971
	/*
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	 * Start arbitration.
	 */

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

978 979 980
	/* The chip now waits for BUS FREE phase. Then after the 800 ns
	 * Bus Free Delay, arbitration will begin.
	 */
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982
	spin_unlock_irq(&hostdata->lock);
983
	err = NCR5380_poll_politely2(hostdata, MODE_REG, MR_ARBITRATE, 0,
984 985
	                INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS,
	                                       ICR_ARBITRATION_PROGRESS, HZ);
986
	spin_lock_irq(&hostdata->lock);
987 988
	if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
		/* Reselection interrupt */
989
		goto out;
990
	}
991 992 993
	if (!hostdata->selecting) {
		/* Command was aborted */
		NCR5380_write(MODE_REG, MR_BASE);
994
		return false;
995
	}
996 997 998 999
	if (err < 0) {
		NCR5380_write(MODE_REG, MR_BASE);
		shost_printk(KERN_ERR, instance,
		             "select: arbitration timeout\n");
1000
		goto out;
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	}
1002
	spin_unlock_irq(&hostdata->lock);
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1004
	/* The SCSI-2 arbitration delay is 2.4 us */
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	udelay(3);

	/* Check for lost arbitration */
1008 1009 1010
	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);
1012
		dsprintk(NDEBUG_ARBITRATION, instance, "lost arbitration, deasserting MR_ARBITRATE\n");
1013
		spin_lock_irq(&hostdata->lock);
1014
		goto out;
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1015
	}
1016 1017 1018 1019 1020 1021 1022

	/* 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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1024 1025
	/*
	 * Again, bus clear + bus settle time is 1.2us, however, this is
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1026 1027 1028
	 * a minimum so we'll udelay ceil(1.2)
	 */

1029 1030 1031 1032
	if (hostdata->flags & FLAG_TOSHIBA_DELAY)
		udelay(15);
	else
		udelay(2);
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1033

1034 1035
	spin_lock_irq(&hostdata->lock);

1036 1037
	/* NCR5380_reselect() clears MODE_REG after a reselection interrupt */
	if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE))
1038 1039 1040 1041 1042
		goto out;

	if (!hostdata->selecting) {
		NCR5380_write(MODE_REG, MR_BASE);
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1043
		return false;
1044
	}
1045

1046
	dsprintk(NDEBUG_ARBITRATION, instance, "won arbitration\n");
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1047

1048 1049
	/*
	 * Now that we have won arbitration, start Selection process, asserting
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1050 1051 1052
	 * the host and target ID's on the SCSI bus.
	 */

1053
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask | (1 << scmd_id(cmd)));
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1054

1055
	/*
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1056 1057 1058 1059 1060
	 * 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.
	 */

1061 1062
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY |
	              ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL);
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1063 1064
	NCR5380_write(MODE_REG, MR_BASE);

1065
	/*
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1066 1067 1068 1069 1070
	 * Reselect interrupts must be turned off prior to the dropping of BSY,
	 * otherwise we will trigger an interrupt.
	 */
	NCR5380_write(SELECT_ENABLE_REG, 0);

1071 1072
	spin_unlock_irq(&hostdata->lock);

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1073
	/*
1074
	 * The initiator shall then wait at least two deskew delays and release
L
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1075 1076
	 * the BSY signal.
	 */
1077
	udelay(1);        /* wingel -- wait two bus deskew delay >2*45ns */
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1078 1079

	/* Reset BSY */
1080 1081
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA |
	              ICR_ASSERT_ATN | ICR_ASSERT_SEL);
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1082

1083
	/*
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1084
	 * Something weird happens when we cease to drive BSY - looks
1085
	 * like the board/chip is letting us do another read before the
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1086 1087 1088 1089 1090
	 * 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
1091 1092 1093
	 * 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);

1102
	dsprintk(NDEBUG_SELECTION, instance, "selecting target %d\n", scmd_id(cmd));
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1103

1104 1105
	/*
	 * The SCSI specification calls for a 250 ms timeout for the actual
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1106 1107 1108
	 * selection.
	 */

1109
	err = NCR5380_poll_politely(hostdata, STATUS_REG, SR_BSY, SR_BSY,
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	                            msecs_to_jiffies(250));
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1111 1112

	if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1113
		spin_lock_irq(&hostdata->lock);
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1114 1115
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		NCR5380_reselect(instance);
1116
		shost_printk(KERN_ERR, instance, "reselection after won arbitration?\n");
1117
		goto out;
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1118
	}
F
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1119 1120

	if (err < 0) {
1121
		spin_lock_irq(&hostdata->lock);
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1122
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1123

1124
		/* Can't touch cmd if it has been reclaimed by the scsi ML */
1125
		if (!hostdata->selecting)
1126
			return false;
1127 1128 1129 1130 1131

		cmd->result = DID_BAD_TARGET << 16;
		complete_cmd(instance, cmd);
		dsprintk(NDEBUG_SELECTION, instance,
			"target did not respond within 250ms\n");
1132
		ret = false;
1133
		goto out;
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1134 1135
	}

1136 1137 1138
	/*
	 * 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);

	/*
1147
	 * Since we followed the SCSI spec, and raised ATN while SEL
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1148 1149 1150 1151 1152 1153 1154
	 * 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 */

1155
	err = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ);
1156
	spin_lock_irq(&hostdata->lock);
1157
	if (err < 0) {
1158 1159
		shost_printk(KERN_ERR, instance, "select: REQ timeout\n");
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1160 1161 1162 1163
		goto out;
	}
	if (!hostdata->selecting) {
		do_abort(instance);
1164
		return false;
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1165 1166
	}

1167 1168
	dsprintk(NDEBUG_SELECTION, instance, "target %d selected, going into MESSAGE OUT phase.\n",
	         scmd_id(cmd));
1169
	tmp[0] = IDENTIFY(can_disconnect, cmd->device->lun);
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1170 1171 1172 1173 1174

	len = 1;
	data = tmp;
	phase = PHASE_MSGOUT;
	NCR5380_transfer_pio(instance, &phase, &len, &data);
1175 1176 1177 1178 1179
	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");
1180
		ret = false;
1181 1182 1183
		goto out;
	}

1184
	dsprintk(NDEBUG_SELECTION, instance, "nexus established.\n");
1185

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1186
	hostdata->connected = cmd;
1187
	hostdata->busy[cmd->device->id] |= 1 << cmd->device->lun;
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1188

1189 1190 1191 1192
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif

1193
	initialize_SCp(cmd);
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1194

1195
	ret = false;
1196 1197 1198 1199 1200

out:
	if (!hostdata->selecting)
		return NULL;
	hostdata->selecting = NULL;
1201
	return ret;
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}

1204 1205
/*
 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1206
 * unsigned char *phase, int *count, unsigned char **data)
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 *
 * Purpose : transfers data in given phase using polled I/O
 *
1210
 * Inputs : instance - instance of driver, *phase - pointer to
1211 1212
 * what phase is expected, *count - pointer to number of
 * bytes to transfer, **data - pointer to data pointer.
1213
 *
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 * Returns : -1 when different phase is entered without transferring
1215
 * maximum number of bytes, 0 if all bytes are transferred or exit
1216
 * is in same phase.
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1217
 *
1218
 * Also, *phase, *count, *data are modified in place.
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1219 1220 1221 1222 1223
 *
 * XXX Note : handling for bus free may be useful.
 */

/*
1224
 * 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.
 */

1229 1230 1231 1232
static int NCR5380_transfer_pio(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
{
1233
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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	unsigned char p = *phase, tmp;
	int c = *count;
	unsigned char *d = *data;

1238 1239
	/*
	 * The NCR5380 chip will only drive the SCSI bus when the
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	 * phase specified in the appropriate bits of the TARGET COMMAND
	 * REGISTER match the STATUS REGISTER
	 */

1244
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
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1245 1246

	do {
1247 1248 1249
		/*
		 * Wait for assertion of REQ, after which the phase bits will be
		 * valid
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1250 1251
		 */

1252
		if (NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ) < 0)
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1253 1254
			break;

1255
		dsprintk(NDEBUG_HANDSHAKE, instance, "REQ asserted\n");
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1256 1257

		/* Check for phase mismatch */
1258
		if ((NCR5380_read(STATUS_REG) & PHASE_MASK) != p) {
1259 1260
			dsprintk(NDEBUG_PIO, instance, "phase mismatch\n");
			NCR5380_dprint_phase(NDEBUG_PIO, instance);
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1261 1262
			break;
		}
1263

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1264 1265 1266 1267 1268 1269 1270 1271
		/* 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;

1272
		/*
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		 * 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);
1283 1284
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ACK);
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1285
			} else {
1286 1287
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ATN);
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				NCR5380_dprint(NDEBUG_PIO, instance);
1289 1290
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
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1291 1292 1293 1294 1295 1296
			}
		} else {
			NCR5380_dprint(NDEBUG_PIO, instance);
			NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
		}

1297
		if (NCR5380_poll_politely(hostdata,
1298 1299 1300
		                          STATUS_REG, SR_REQ, 0, 5 * HZ) < 0)
			break;

1301
		dsprintk(NDEBUG_HANDSHAKE, instance, "REQ negated, handshake complete\n");
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1302 1303

/*
1304 1305
 * 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
1306
 * message.  ATN must be dropped as ACK is dropped.
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1307
 *
1308
 * 2.  We are in a MSGIN phase, and we are on the last byte of the
1309 1310
 * 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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1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321
 *
 * 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);

1322
	dsprintk(NDEBUG_PIO, instance, "residual %d\n", c);
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1323 1324 1325 1326

	*count = c;
	*data = d;
	tmp = NCR5380_read(STATUS_REG);
1327 1328 1329 1330 1331
	/* 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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1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342
		*phase = tmp & PHASE_MASK;
	else
		*phase = PHASE_UNKNOWN;

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

/**
1343 1344
 * do_reset - issue a reset command
 * @instance: adapter to reset
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1345
 *
1346 1347
 * Issue a reset sequence to the NCR5380 and try and get the bus
 * back into sane shape.
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1348
 *
1349 1350 1351
 * 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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 */
1353

1354 1355
static void do_reset(struct Scsi_Host *instance)
{
1356
	struct NCR5380_hostdata __maybe_unused *hostdata = shost_priv(instance);
1357 1358 1359 1360 1361
	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);
1363
	udelay(50);
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	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1365 1366
	(void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
	local_irq_restore(flags);
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1367 1368
}

1369 1370 1371 1372
/**
 * 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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1373
 *
1374
 * Returns 0 on success, -1 on failure.
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1375 1376
 */

1377 1378
static int do_abort(struct Scsi_Host *instance)
{
1379
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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1380 1381 1382 1383 1384 1385 1386
	unsigned char *msgptr, phase, tmp;
	int len;
	int rc;

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

1387 1388 1389 1390
	/*
	 * 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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1391
	 * other phase and will have to source/sink data.
1392
	 *
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1393 1394 1395 1396
	 * We really don't care what value was on the bus or what value
	 * the target sees, so we just handshake.
	 */

1397
	rc = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, 10 * HZ);
1398
	if (rc < 0)
1399
		goto timeout;
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1400

1401
	tmp = NCR5380_read(STATUS_REG) & PHASE_MASK;
1402

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1403 1404
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

1405
	if (tmp != PHASE_MSGOUT) {
1406 1407
		NCR5380_write(INITIATOR_COMMAND_REG,
		              ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1408
		rc = NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, 0, 3 * HZ);
1409
		if (rc < 0)
1410 1411
			goto timeout;
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
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1412
	}
1413

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1414 1415 1416 1417
	tmp = ABORT;
	msgptr = &tmp;
	len = 1;
	phase = PHASE_MSGOUT;
1418
	NCR5380_transfer_pio(instance, &phase, &len, &msgptr);
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1419 1420 1421 1422 1423 1424 1425

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

	return len ? -1 : 0;
1426 1427 1428 1429

timeout:
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
	return -1;
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1430 1431
}

1432 1433
/*
 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1434
 * unsigned char *phase, int *count, unsigned char **data)
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1435 1436
 *
 * Purpose : transfers data in given phase using either real
1437
 * or pseudo DMA.
L
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1438
 *
1439
 * Inputs : instance - instance of driver, *phase - pointer to
1440 1441
 * what phase is expected, *count - pointer to number of
 * bytes to transfer, **data - pointer to data pointer.
1442
 *
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1443
 * Returns : -1 when different phase is entered without transferring
1444 1445
 * maximum number of bytes, 0 if all bytes or transferred or exit
 * is in same phase.
L
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1446
 *
1447
 * Also, *phase, *count, *data are modified in place.
L
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1448 1449 1450
 */


1451 1452 1453 1454 1455
static int NCR5380_transfer_dma(struct Scsi_Host *instance,
				unsigned char *phase, int *count,
				unsigned char **data)
{
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
1456 1457 1458
	int c = *count;
	unsigned char p = *phase;
	unsigned char *d = *data;
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1459
	unsigned char tmp;
1460
	int result = 0;
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1461 1462 1463 1464 1465 1466

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

1467
	hostdata->connected->SCp.phase = p;
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1468

1469 1470 1471 1472 1473 1474
	if (p & SR_IO) {
		if (hostdata->read_overruns)
			c -= hostdata->read_overruns;
		else if (hostdata->flags & FLAG_DMA_FIXUP)
			--c;
	}
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1475

1476 1477
	dsprintk(NDEBUG_DMA, instance, "initializing DMA %s: length %d, address %p\n",
	         (p & SR_IO) ? "receive" : "send", c, d);
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1478

1479 1480 1481 1482 1483
#ifdef CONFIG_SUN3
	/* send start chain */
	sun3scsi_dma_start(c, *data);
#endif

1484 1485 1486 1487 1488 1489 1490 1491 1492
	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)
1493
			result = NCR5380_dma_recv_setup(hostdata, d, c);
1494
		else
1495
			result = NCR5380_dma_send_setup(hostdata, d, c);
1496
	}
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1497

1498
	/*
1499 1500
	 * On the PAS16 at least I/O recovery delays are not needed here.
	 * Everyone else seems to want them.
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1501 1502 1503
	 */

	if (p & SR_IO) {
1504
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1505
		NCR5380_io_delay(1);
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1506 1507
		NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
	} else {
1508
		NCR5380_io_delay(1);
L
Linus Torvalds 已提交
1509
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1510
		NCR5380_io_delay(1);
L
Linus Torvalds 已提交
1511
		NCR5380_write(START_DMA_SEND_REG, 0);
1512
		NCR5380_io_delay(1);
L
Linus Torvalds 已提交
1513 1514
	}

1515 1516 1517 1518 1519 1520 1521
#ifdef CONFIG_SUN3
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_DMA_ENABLE;
#endif
	sun3_dma_active = 1;
#endif

1522 1523 1524 1525 1526
	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)
1527
			result = NCR5380_dma_recv_setup(hostdata, d, c);
1528
		else
1529
			result = NCR5380_dma_send_setup(hostdata, d, c);
1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544
	}

	/* 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
1545
/*
1546
 * A note regarding the DMA errata workarounds for early NMOS silicon.
F
Finn Thain 已提交
1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572
 *
 * 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
1573
 * problem.  The chosen fix is to DMA fewer bytes, then check for the
F
Finn Thain 已提交
1574 1575 1576
 * 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
1577 1578
 */

1579 1580
	if (hostdata->flags & FLAG_DMA_FIXUP) {
		if (p & SR_IO) {
L
Linus Torvalds 已提交
1581
			/*
1582
			 * The workaround was to transfer fewer bytes than we
1583
			 * intended to with the pseudo-DMA read function, wait for
L
Linus Torvalds 已提交
1584 1585
			 * the chip to latch the last byte, read it, and then disable
			 * pseudo-DMA mode.
1586
			 *
L
Linus Torvalds 已提交
1587 1588 1589 1590
			 * 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
1591 1592
			 * 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
1593 1594 1595
			 * byte.
			 */

1596
			if (NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG,
1597
			                          BASR_DRQ, BASR_DRQ, HZ) < 0) {
1598
				result = -1;
1599 1600
				shost_printk(KERN_ERR, instance, "PDMA read: DRQ timeout\n");
			}
1601
			if (NCR5380_poll_politely(hostdata, STATUS_REG,
1602
			                          SR_REQ, 0, HZ) < 0) {
1603
				result = -1;
1604
				shost_printk(KERN_ERR, instance, "PDMA read: !REQ timeout\n");
L
Linus Torvalds 已提交
1605
			}
1606 1607
			d[*count - 1] = NCR5380_read(INPUT_DATA_REG);
		} else {
L
Linus Torvalds 已提交
1608
			/*
1609 1610
			 * 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
1611
			 */
1612
			if (NCR5380_poll_politely2(hostdata,
1613 1614
			     BUS_AND_STATUS_REG, BASR_DRQ, BASR_DRQ,
			     BUS_AND_STATUS_REG, BASR_PHASE_MATCH, 0, HZ) < 0) {
1615
				result = -1;
1616
				shost_printk(KERN_ERR, instance, "PDMA write: DRQ and phase timeout\n");
L
Linus Torvalds 已提交
1617 1618 1619
			}
		}
	}
1620 1621

	NCR5380_dma_complete(instance);
1622
	return result;
L
Linus Torvalds 已提交
1623 1624 1625 1626 1627
}

/*
 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
 *
1628
 * Purpose : run through the various SCSI phases and do as the target
1629 1630
 * directs us to.  Operates on the currently connected command,
 * instance->connected.
L
Linus Torvalds 已提交
1631 1632 1633
 *
 * Inputs : instance, instance for which we are doing commands
 *
1634
 * Side effects : SCSI things happen, the disconnected queue will be
1635 1636
 * modified if a command disconnects, *instance->connected will
 * change.
L
Linus Torvalds 已提交
1637
 *
1638
 * XXX Note : we need to watch for bus free or a reset condition here
1639
 * to recover from an unexpected bus free condition.
L
Linus Torvalds 已提交
1640 1641
 */

1642
static void NCR5380_information_transfer(struct Scsi_Host *instance)
1643
	__releases(&hostdata->lock) __acquires(&hostdata->lock)
1644
{
F
Finn Thain 已提交
1645
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
L
Linus Torvalds 已提交
1646 1647 1648 1649 1650 1651
	unsigned char msgout = NOP;
	int sink = 0;
	int len;
	int transfersize;
	unsigned char *data;
	unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
1652
	struct scsi_cmnd *cmd;
L
Linus Torvalds 已提交
1653

1654 1655 1656 1657
#ifdef SUN3_SCSI_VME
	dregs->csr |= CSR_INTR;
#endif

1658
	while ((cmd = hostdata->connected)) {
1659 1660
		struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);

L
Linus Torvalds 已提交
1661 1662 1663 1664 1665 1666 1667 1668
		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);
			}
1669
#ifdef CONFIG_SUN3
1670 1671 1672
			if (phase == PHASE_CMDOUT &&
			    sun3_dma_setup_done != cmd) {
				int count;
1673 1674

				if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
1675 1676 1677 1678
					++cmd->SCp.buffer;
					--cmd->SCp.buffers_residual;
					cmd->SCp.this_residual = cmd->SCp.buffer->length;
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
1679 1680
				}

1681 1682 1683 1684 1685 1686 1687 1688 1689
				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);
1690 1691 1692 1693 1694 1695 1696 1697
					sun3_dma_setup_done = cmd;
				}
#ifdef SUN3_SCSI_VME
				dregs->csr |= CSR_INTR;
#endif
			}
#endif /* CONFIG_SUN3 */

L
Linus Torvalds 已提交
1698 1699 1700
			if (sink && (phase != PHASE_MSGOUT)) {
				NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));

1701 1702
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
				              ICR_ASSERT_ACK);
1703 1704
				while (NCR5380_read(STATUS_REG) & SR_REQ)
					;
1705 1706
				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
				              ICR_ASSERT_ATN);
L
Linus Torvalds 已提交
1707 1708 1709
				sink = 0;
				continue;
			}
1710

L
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1711 1712 1713
			switch (phase) {
			case PHASE_DATAOUT:
#if (NDEBUG & NDEBUG_NO_DATAOUT)
1714
				shost_printk(KERN_DEBUG, instance, "NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n");
L
Linus Torvalds 已提交
1715 1716 1717
				sink = 1;
				do_abort(instance);
				cmd->result = DID_ERROR << 16;
1718
				complete_cmd(instance, cmd);
F
Finn Thain 已提交
1719
				hostdata->connected = NULL;
1720
				hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
L
Linus Torvalds 已提交
1721 1722
				return;
#endif
F
Finn Thain 已提交
1723
			case PHASE_DATAIN:
1724
				/*
L
Linus Torvalds 已提交
1725 1726 1727 1728 1729 1730 1731 1732
				 * 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
1733
					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
1734 1735 1736
					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
1737
				}
1738

L
Linus Torvalds 已提交
1739
				/*
1740
				 * The preferred transfer method is going to be
L
Linus Torvalds 已提交
1741 1742 1743 1744 1745 1746 1747 1748
				 * 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.
				 */

1749
				transfersize = 0;
1750
				if (!cmd->device->borken)
1751
					transfersize = NCR5380_dma_xfer_len(hostdata, cmd);
1752

1753
				if (transfersize > 0) {
L
Linus Torvalds 已提交
1754
					len = transfersize;
1755 1756
					if (NCR5380_transfer_dma(instance, &phase,
					    &len, (unsigned char **)&cmd->SCp.ptr)) {
L
Linus Torvalds 已提交
1757
						/*
1758 1759 1760
						 * If the watchdog timer fires, all future
						 * accesses to this device will use the
						 * polled-IO.
L
Linus Torvalds 已提交
1761
						 */
J
Jeff Garzik 已提交
1762
						scmd_printk(KERN_INFO, cmd,
1763
							"switching to slow handshake\n");
L
Linus Torvalds 已提交
1764 1765 1766 1767 1768
						cmd->device->borken = 1;
						sink = 1;
						do_abort(instance);
						cmd->result = DID_ERROR << 16;
						/* XXX - need to source or sink data here, as appropriate */
1769
					}
F
Finn Thain 已提交
1770
				} else {
1771 1772
					/* Transfer a small chunk so that the
					 * irq mode lock is not held too long.
1773
					 */
1774 1775
					transfersize = min(cmd->SCp.this_residual,
							   NCR5380_PIO_CHUNK_SIZE);
1776 1777
					len = transfersize;
					NCR5380_transfer_pio(instance, &phase, &len,
1778
					                     (unsigned char **)&cmd->SCp.ptr);
1779
					cmd->SCp.this_residual -= transfersize - len;
1780
				}
1781 1782 1783 1784
#ifdef CONFIG_SUN3
				if (sun3_dma_setup_done == cmd)
					sun3_dma_setup_done = NULL;
#endif
1785
				return;
L
Linus Torvalds 已提交
1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797
			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);
1798 1799 1800 1801
					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
1802
					hostdata->connected = NULL;
1803
					hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
L
Linus Torvalds 已提交
1804

F
Finn Thain 已提交
1805 1806 1807
					cmd->result &= ~0xffff;
					cmd->result |= cmd->SCp.Status;
					cmd->result |= cmd->SCp.Message << 8;
1808

F
Finn Thain 已提交
1809
					if (cmd->cmnd[0] == REQUEST_SENSE)
1810
						complete_cmd(instance, cmd);
F
Finn Thain 已提交
1811 1812 1813 1814 1815 1816 1817 1818 1819
					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
1820 1821
					}

1822 1823
					/*
					 * Restore phase bits to 0 so an interrupted selection,
L
Linus Torvalds 已提交
1824 1825 1826
					 * arbitration can resume.
					 */
					NCR5380_write(TARGET_COMMAND_REG, 0);
1827

1828
					maybe_release_dma_irq(instance);
L
Linus Torvalds 已提交
1829 1830 1831 1832 1833 1834 1835 1836 1837
					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
1838
						hostdata->busy[cmd->device->id] |= (1 << (cmd->device->lun & 0xFF));
L
Linus Torvalds 已提交
1839 1840 1841 1842
						break;
					default:
						break;
					}
1843
					break;
1844 1845 1846 1847 1848 1849 1850 1851
				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);
1852

1853 1854 1855 1856 1857
					/*
					 * Restore phase bits to 0 so an interrupted selection,
					 * arbitration can resume.
					 */
					NCR5380_write(TARGET_COMMAND_REG, 0);
L
Linus Torvalds 已提交
1858

1859 1860 1861
#ifdef SUN3_SCSI_VME
					dregs->csr |= CSR_DMA_ENABLE;
#endif
1862
					return;
1863
					/*
L
Linus Torvalds 已提交
1864
					 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
1865
					 * operation, in violation of the SCSI spec so we can safely
L
Linus Torvalds 已提交
1866 1867
					 * ignore SAVE/RESTORE pointers calls.
					 *
1868
					 * Unfortunately, some disks violate the SCSI spec and
L
Linus Torvalds 已提交
1869
					 * don't issue the required SAVE_POINTERS message before
1870
					 * disconnecting, and we have to break spec to remain
L
Linus Torvalds 已提交
1871 1872 1873 1874 1875 1876 1877 1878
					 * 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
1879 1880 1881 1882
					/*
					 * Start the message buffer with the EXTENDED_MESSAGE
					 * byte, since spi_print_msg() wants the whole thing.
					 */
L
Linus Torvalds 已提交
1883 1884 1885
					extended_msg[0] = EXTENDED_MESSAGE;
					/* Accept first byte by clearing ACK */
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1886 1887 1888

					spin_unlock_irq(&hostdata->lock);

1889
					dsprintk(NDEBUG_EXTENDED, instance, "receiving extended message\n");
L
Linus Torvalds 已提交
1890 1891 1892 1893 1894

					len = 2;
					data = extended_msg + 1;
					phase = PHASE_MSGIN;
					NCR5380_transfer_pio(instance, &phase, &len, &data);
1895 1896 1897
					dsprintk(NDEBUG_EXTENDED, instance, "length %d, code 0x%02x\n",
					         (int)extended_msg[1],
					         (int)extended_msg[2]);
L
Linus Torvalds 已提交
1898

1899 1900
					if (!len && extended_msg[1] > 0 &&
					    extended_msg[1] <= sizeof(extended_msg) - 2) {
L
Linus Torvalds 已提交
1901 1902 1903 1904 1905 1906 1907
						/* 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);
1908 1909
						dsprintk(NDEBUG_EXTENDED, instance, "message received, residual %d\n",
						         len);
L
Linus Torvalds 已提交
1910 1911 1912 1913 1914 1915 1916

						switch (extended_msg[2]) {
						case EXTENDED_SDTR:
						case EXTENDED_WDTR:
							tmp = 0;
						}
					} else if (len) {
1917
						shost_printk(KERN_ERR, instance, "error receiving extended message\n");
L
Linus Torvalds 已提交
1918 1919
						tmp = 0;
					} else {
1920 1921
						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
1922 1923
						tmp = 0;
					}
1924 1925 1926 1927 1928

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

L
Linus Torvalds 已提交
1929 1930
					/* Fall through to reject message */

1931 1932
					/*
					 * If we get something weird that we aren't expecting,
L
Linus Torvalds 已提交
1933 1934 1935
					 * reject it.
					 */
				default:
1936
					if (tmp == EXTENDED_MESSAGE)
J
Jeff Garzik 已提交
1937
						scmd_printk(KERN_INFO, cmd,
1938
						            "rejecting unknown extended message code %02x, length %d\n",
1939 1940 1941 1942 1943
						            extended_msg[2], extended_msg[1]);
					else if (tmp)
						scmd_printk(KERN_INFO, cmd,
						            "rejecting unknown message code %02x\n",
						            tmp);
L
Linus Torvalds 已提交
1944 1945 1946 1947

					msgout = MESSAGE_REJECT;
					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
					break;
1948
				} /* switch (tmp) */
L
Linus Torvalds 已提交
1949 1950 1951 1952 1953 1954 1955 1956
				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;
1957
					hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
L
Linus Torvalds 已提交
1958
					cmd->result = DID_ERROR << 16;
1959
					complete_cmd(instance, cmd);
1960
					maybe_release_dma_irq(instance);
L
Linus Torvalds 已提交
1961 1962 1963 1964 1965 1966 1967
					return;
				}
				msgout = NOP;
				break;
			case PHASE_CMDOUT:
				len = cmd->cmd_len;
				data = cmd->cmnd;
1968 1969 1970 1971
				/*
				 * 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
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981
				 */
				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:
1982
				shost_printk(KERN_ERR, instance, "unknown phase\n");
1983
				NCR5380_dprint(NDEBUG_ANY, instance);
1984
			} /* switch(phase) */
1985
		} else {
1986
			spin_unlock_irq(&hostdata->lock);
1987
			NCR5380_poll_politely(hostdata, STATUS_REG, SR_REQ, SR_REQ, HZ);
1988
			spin_lock_irq(&hostdata->lock);
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		}
1990
	}
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1991 1992 1993 1994 1995
}

/*
 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
 *
1996
 * Purpose : does reselection, initializing the instance->connected
1997 1998
 * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
 * nexus has been reestablished,
1999
 *
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 * Inputs : instance - this instance of the NCR5380.
 */

2003 2004
static void NCR5380_reselect(struct Scsi_Host *instance)
{
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	struct NCR5380_hostdata *hostdata = shost_priv(instance);
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2006
	unsigned char target_mask;
2007
	unsigned char lun;
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2008
	unsigned char msg[3];
2009 2010
	struct NCR5380_cmd *ncmd;
	struct scsi_cmnd *tmp;
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2011 2012 2013 2014 2015 2016 2017 2018 2019

	/*
	 * 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);
2020 2021 2022 2023 2024
	if (!target_mask || target_mask & (target_mask - 1)) {
		shost_printk(KERN_WARNING, instance,
			     "reselect: bad target_mask 0x%02x\n", target_mask);
		return;
	}
2025

2026
	/*
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2027 2028 2029 2030 2031 2032 2033 2034 2035
	 * 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);
2036
	if (NCR5380_poll_politely(hostdata,
2037
	                          STATUS_REG, SR_SEL, 0, 2 * HZ) < 0) {
2038
		shost_printk(KERN_ERR, instance, "reselect: !SEL timeout\n");
2039 2040 2041
		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
		return;
	}
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2042 2043 2044 2045 2046 2047
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

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

2048
	if (NCR5380_poll_politely(hostdata,
2049
	                          STATUS_REG, SR_REQ, SR_REQ, 2 * HZ) < 0) {
2050 2051 2052
		if ((NCR5380_read(STATUS_REG) & (SR_BSY | SR_SEL)) == 0)
			/* BUS FREE phase */
			return;
2053
		shost_printk(KERN_ERR, instance, "reselect: REQ timeout\n");
2054 2055 2056
		do_abort(instance);
		return;
	}
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2057

2058 2059 2060
#ifdef CONFIG_SUN3
	/* acknowledge toggle to MSGIN */
	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN));
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2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075
	/* 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;
		}
2076
	}
2077
#endif /* CONFIG_SUN3 */
2078

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2079
	if (!(msg[0] & 0x80)) {
2080
		shost_printk(KERN_ERR, instance, "expecting IDENTIFY message, got ");
2081
		spi_print_msg(msg);
2082 2083 2084 2085 2086
		printk("\n");
		do_abort(instance);
		return;
	}
	lun = msg[0] & 0x07;
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2088 2089 2090 2091 2092
	/*
	 * 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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2094 2095 2096 2097
	/*
	 * 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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2099 2100 2101 2102 2103 2104 2105 2106
	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;
2107
			break;
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2108 2109
		}
	}
2110 2111 2112 2113 2114

	if (tmp) {
		dsprintk(NDEBUG_RESELECTION | NDEBUG_QUEUES, instance,
		         "reselect: removed %p from disconnected queue\n", tmp);
	} else {
2115 2116
		int target = ffs(target_mask) - 1;

2117 2118 2119
		shost_printk(KERN_ERR, instance, "target bitmask 0x%02x lun %d not in disconnected queue.\n",
		             target_mask, lun);
		/*
2120 2121
		 * Since we have an established nexus that we can't do anything
		 * with, we must abort it.
2122
		 */
2123 2124
		if (do_abort(instance) == 0)
			hostdata->busy[target] &= ~(1 << lun);
2125
		return;
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2126
	}
2127

2128
#ifdef CONFIG_SUN3
2129 2130
	if (sun3_dma_setup_done != tmp) {
		int count;
2131 2132

		if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
2133 2134 2135 2136
			++tmp->SCp.buffer;
			--tmp->SCp.buffers_residual;
			tmp->SCp.this_residual = tmp->SCp.buffer->length;
			tmp->SCp.ptr = sg_virt(tmp->SCp.buffer);
2137 2138
		}

2139 2140 2141 2142 2143 2144 2145 2146 2147
		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);
2148 2149 2150 2151 2152 2153 2154
			sun3_dma_setup_done = tmp;
		}
	}

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

2155 2156 2157 2158
	/* Accept message by clearing ACK */
	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

	hostdata->connected = tmp;
2159 2160
	dsprintk(NDEBUG_RESELECTION, instance, "nexus established, target %d, lun %llu\n",
	         scmd_id(tmp), tmp->device->lun);
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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 2207 2208 2209 2210 2211 2212 2213 2214 2215
/**
 * 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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2216
 *
2217
 * If the command has not completed yet, we must not fail to find it.
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2218 2219 2220 2221
 * 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.
2222 2223 2224
 *
 * 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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2225 2226
 */

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2227 2228
static int NCR5380_abort(struct scsi_cmnd *cmd)
{
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2229
	struct Scsi_Host *instance = cmd->device->host;
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2230
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
2231
	unsigned long flags;
2232
	int result = SUCCESS;
2233

2234 2235
	spin_lock_irqsave(&hostdata->lock, flags);

2236
#if (NDEBUG & NDEBUG_ANY)
2237
	scmd_printk(KERN_INFO, cmd, __func__);
2238
#endif
2239 2240
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);
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2241

2242 2243 2244 2245 2246
	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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2247
		goto out;
2248 2249
	}

2250 2251 2252 2253 2254 2255 2256 2257 2258
	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;
	}

2259 2260 2261
	if (list_del_cmd(&hostdata->disconnected, cmd)) {
		dsprintk(NDEBUG_ABORT, instance,
		         "abort: removed %p from disconnected list\n", cmd);
2262 2263 2264
		/* Can't call NCR5380_select() and send ABORT because that
		 * means releasing the lock. Need a bus reset.
		 */
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2265 2266
		set_host_byte(cmd, DID_ERROR);
		complete_cmd(instance, cmd);
2267 2268
		result = FAILED;
		goto out;
2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281
	}

	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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2282 2283 2284 2285 2286 2287 2288
		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);
2289 2290 2291 2292 2293 2294
		complete_cmd(instance, cmd);
	}

out:
	if (result == FAILED)
		dsprintk(NDEBUG_ABORT, instance, "abort: failed to abort %p\n", cmd);
2295 2296
	else {
		hostdata->busy[scmd_id(cmd)] &= ~(1 << cmd->device->lun);
2297
		dsprintk(NDEBUG_ABORT, instance, "abort: successfully aborted %p\n", cmd);
2298
	}
2299 2300

	queue_work(hostdata->work_q, &hostdata->main_task);
2301
	maybe_release_dma_irq(instance);
2302
	spin_unlock_irqrestore(&hostdata->lock, flags);
2303

2304
	return result;
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2305 2306 2307
}


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2308
static void bus_reset_cleanup(struct Scsi_Host *instance)
2309
{
2310
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
2311 2312
	int i;
	struct NCR5380_cmd *ncmd;
2313

2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324
	/* 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!
	 */

2325 2326 2327 2328 2329
	if (hostdata->selecting) {
		hostdata->selecting->result = DID_RESET << 16;
		complete_cmd(instance, hostdata->selecting);
		hostdata->selecting = NULL;
	}
2330 2331 2332 2333 2334

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

		set_host_byte(cmd, DID_RESET);
2335
		complete_cmd(instance, cmd);
2336
	}
2337
	INIT_LIST_HEAD(&hostdata->disconnected);
2338 2339 2340 2341 2342 2343

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

		cmd->scsi_done(cmd);
	}
2344
	INIT_LIST_HEAD(&hostdata->autosense);
2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356

	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);
2357
	maybe_release_dma_irq(instance);
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2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392
}

/**
 * NCR5380_host_reset - reset the SCSI host
 * @cmd: SCSI command undergoing EH
 *
 * Returns SUCCESS
 */

static int NCR5380_host_reset(struct scsi_cmnd *cmd)
{
	struct Scsi_Host *instance = cmd->device->host;
	struct NCR5380_hostdata *hostdata = shost_priv(instance);
	unsigned long flags;
	struct NCR5380_cmd *ncmd;

	spin_lock_irqsave(&hostdata->lock, flags);

#if (NDEBUG & NDEBUG_ANY)
	shost_printk(KERN_INFO, instance, __func__);
#endif
	NCR5380_dprint(NDEBUG_ANY, instance);
	NCR5380_dprint_phase(NDEBUG_ANY, instance);

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

		scmd->result = DID_RESET << 16;
		scmd->scsi_done(scmd);
	}
	INIT_LIST_HEAD(&hostdata->unissued);

	do_reset(instance);
	bus_reset_cleanup(instance);

2393
	spin_unlock_irqrestore(&hostdata->lock, flags);
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2394 2395 2396

	return SUCCESS;
}