Commit 55500d9b authored by Finn Thain's avatar Finn Thain Committed by Martin K. Petersen
Browse files

atari_NCR5380: Use arbitration timeout 



Allow target selection to fail with a timeout instead of waiting in
infinite loops. This gets rid of the unused NCR_TIMEOUT macro, it is more
defensive and has proved helpful in debugging.

Signed-off-by: default avatarFinn Thain <fthain@telegraphics.com.au>
Reviewed-by: default avatarHannes Reinecke <hare@suse.com>
Tested-by: default avatarOndrej Zary <linux@rainbow-software.org>
Tested-by: default avatarMichael Schmitz <schmitzmic@gmail.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 80d3eb6d

drivers/scsi/NCR5380.c

+24 −20
Original line number Diff line number Diff line
@@ -1083,6 +1083,7 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) 
	unsigned char *data;

	int len;

	int err;

	unsigned long timeout;



	NCR5380_dprint(NDEBUG_ARBITRATION, instance);

	dprintk(NDEBUG_ARBITRATION, "scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id);
@@ -1101,28 +1102,31 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) 
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);

	NCR5380_write(MODE_REG, MR_ARBITRATE);



	/* The chip now waits for BUS FREE phase. Then after the 800 ns

	 * Bus Free Delay, arbitration will begin.

	 */



	/* We can be relaxed here, interrupts are on, we are

	   in workqueue context, the birds are singing in the trees */

	spin_unlock_irq(instance->host_lock);

	err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ);

	spin_lock_irq(instance->host_lock);

	if (err < 0) {

		printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__);

	timeout = jiffies + HZ;

	while (1) {

		if (time_is_before_jiffies(timeout)) {

			NCR5380_write(MODE_REG, MR_BASE);

		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);

			shost_printk(KERN_ERR, instance,

			             "select: arbitration timeout\n");

			spin_lock_irq(instance->host_lock);

			return -1;

		}

		spin_lock_irq(instance->host_lock);

		if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {

			/* Reselection interrupt */

			return -1;

		}

		if (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)

			break;

		spin_unlock_irq(instance->host_lock);

	}



	dprintk(NDEBUG_ARBITRATION, "scsi%d : arbitration complete\n", instance->host_no);



	/* 

	 * The arbitration delay is 2.2us, but this is a minimum and there is 

	 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate

	 * the integral nature of udelay().

	 *

	 */



	/* The SCSI-2 arbitration delay is 2.4 us */

	udelay(3);



	/* Check for lost arbitration */
@@ -1270,9 +1274,9 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) 
	spin_unlock_irq(instance->host_lock);

	err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);

	spin_lock_irq(instance->host_lock);

	

	if (err < 0) {

		printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__);

		shost_printk(KERN_ERR, instance, "select: REQ timeout\n");

		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);

		return -1;

	}

drivers/scsi/atari_NCR5380.c

+25 −32
Original line number Diff line number Diff line
@@ -1412,6 +1412,7 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) 
	int len;

	int err;

	unsigned long flags;

	unsigned long timeout;



	NCR5380_dprint(NDEBUG_ARBITRATION, instance);

	dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", HOSTNO,
@@ -1436,42 +1437,28 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) 
	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);

	NCR5380_write(MODE_REG, MR_ARBITRATE);



	local_irq_restore(flags);



	/* Wait for arbitration logic to complete */

#if defined(NCR_TIMEOUT)

	{

		unsigned long timeout = jiffies + 2*NCR_TIMEOUT;

	/* The chip now waits for BUS FREE phase. Then after the 800 ns

	 * Bus Free Delay, arbitration will begin.

	 */



		while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&

		       time_before(jiffies, timeout) && !hostdata->connected)

			;

		if (time_after_eq(jiffies, timeout)) {

			printk("scsi : arbitration timeout at %d\n", __LINE__);

	local_irq_restore(flags);

	timeout = jiffies + HZ;

	while (1) {

		if (time_is_before_jiffies(timeout)) {

			NCR5380_write(MODE_REG, MR_BASE);

			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);

			shost_printk(KERN_ERR, instance,

			             "select: arbitration timeout\n");

			return -1;

		}

	}

#else /* NCR_TIMEOUT */

	while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&

	       !hostdata->connected)

		;

#endif



	dprintk(NDEBUG_ARBITRATION, "scsi%d: arbitration complete\n", HOSTNO);



	if (hostdata->connected) {

		NCR5380_write(MODE_REG, MR_BASE);

		if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {

			/* Reselection interrupt */

			return -1;

		}

	/*

	 * The arbitration delay is 2.2us, but this is a minimum and there is

	 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate

	 * the integral nature of udelay().

	 *

	 */

		if (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)

			break;

	}



	/* The SCSI-2 arbitration delay is 2.4 us */

	udelay(3);



	/* Check for lost arbitration */
@@ -1634,8 +1621,14 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) 
	 */



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

	while (!(NCR5380_read(STATUS_REG) & SR_REQ))

		;



	err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);

	if (err < 0) {

		shost_printk(KERN_ERR, instance, "select: REQ timeout\n");

		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);

		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);

		return -1;

	}



	dprintk(NDEBUG_SELECTION, "scsi%d: target %d selected, going into MESSAGE OUT phase.\n",

		   HOSTNO, cmd->device->id);

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