Commit b32ade12 authored by Finn Thain's avatar Finn Thain Committed by Martin K. Petersen
Browse files

ncr5380: Introduce NCR5380_poll_politely2 



SCSI bus protocol sometimes requires monitoring two related conditions
simultaneously. Enhance NCR5380_poll_politely() for this purpose, and
put it to use in the arbitration algorithm. It will also find use in
pseudo DMA.

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 cd400825

drivers/scsi/NCR5380.c

+38 −28
Original line number Diff line number Diff line
@@ -262,11 +262,14 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd) 
}



/**

 * NCR5380_poll_politely - wait for chip register value

 * NCR5380_poll_politely2 - wait for two chip register values

 * @instance: controller to poll

 * @reg: 5380 register to poll

 * @bit: Bitmask to check

 * @val: Value required to exit

 * @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

 * @wait: Time-out in jiffies

 *

 * Polls the chip in a reasonably efficient manner waiting for an
@@ -274,11 +277,12 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd) 
 * (if possible). In irq contexts the time-out is arbitrarily limited.

 * Callers may hold locks as long as they are held in irq mode.

 *

 * Returns 0 if event occurred otherwise -ETIMEDOUT.

 * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.

 */



static int NCR5380_poll_politely(struct Scsi_Host *instance,

                                 int reg, int bit, int val, int wait)

static int NCR5380_poll_politely2(struct Scsi_Host *instance,

                                  int reg1, int bit1, int val1,

                                  int reg2, int bit2, int val2, int wait)

{

	struct NCR5380_hostdata *hostdata = shost_priv(instance);

	unsigned long deadline = jiffies + wait;
@@ -287,9 +291,11 @@ static int NCR5380_poll_politely(struct Scsi_Host *instance, 
	/* Busy-wait for up to 10 ms */

	n = min(10000U, jiffies_to_usecs(wait));

	n *= hostdata->accesses_per_ms;

	n /= 1000;

	n /= 2000;

	do {

		if ((NCR5380_read(reg) & bit) == val)

		if ((NCR5380_read(reg1) & bit1) == val1)

			return 0;

		if ((NCR5380_read(reg2) & bit2) == val2)

			return 0;

		cpu_relax();

	} while (n--);
@@ -300,13 +306,22 @@ static int NCR5380_poll_politely(struct Scsi_Host *instance, 
	/* Repeatedly sleep for 1 ms until deadline */

	while (time_is_after_jiffies(deadline)) {

		schedule_timeout_uninterruptible(1);

		if ((NCR5380_read(reg) & bit) == val)

		if ((NCR5380_read(reg1) & bit1) == val1)

			return 0;

		if ((NCR5380_read(reg2) & bit2) == val2)

			return 0;

	}



	return -ETIMEDOUT;

}



static inline int NCR5380_poll_politely(struct Scsi_Host *instance,

                                        int reg, int bit, int val, int wait)

{

	return NCR5380_poll_politely2(instance, reg, bit, val,

	                                        reg, bit, val, wait);

}



static struct {

	unsigned char value;

	const char *name;
@@ -1101,7 +1116,6 @@ 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);
@@ -1125,23 +1139,19 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) 
	 */



	spin_unlock_irq(instance->host_lock);

	timeout = jiffies + HZ;

	while (1) {

		if (time_is_before_jiffies(timeout)) {

			NCR5380_write(MODE_REG, MR_BASE);

			shost_printk(KERN_ERR, instance,

			             "select: arbitration timeout\n");

			spin_lock_irq(instance->host_lock);

			return -1;

		}

	err = NCR5380_poll_politely2(instance, MODE_REG, MR_ARBITRATE, 0,

	                INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS,

	                                       ICR_ARBITRATION_PROGRESS, HZ);

	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);

	if (err < 0) {

		NCR5380_write(MODE_REG, MR_BASE);

		shost_printk(KERN_ERR, instance,

		             "select: arbitration timeout\n");

		return -1;

	}



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

drivers/scsi/atari_NCR5380.c

+37 −25
Original line number Diff line number Diff line
@@ -457,11 +457,14 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd) 
}



/**

 * NCR5380_poll_politely - wait for chip register value

 * NCR5380_poll_politely2 - wait for two chip register values

 * @instance: controller to poll

 * @reg: 5380 register to poll

 * @bit: Bitmask to check

 * @val: Value required to exit

 * @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

 * @wait: Time-out in jiffies

 *

 * Polls the chip in a reasonably efficient manner waiting for an
@@ -469,11 +472,12 @@ static inline void initialize_SCp(struct scsi_cmnd *cmd) 
 * (if possible). In irq contexts the time-out is arbitrarily limited.

 * Callers may hold locks as long as they are held in irq mode.

 *

 * Returns 0 if event occurred otherwise -ETIMEDOUT.

 * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.

 */



static int NCR5380_poll_politely(struct Scsi_Host *instance,

                                 int reg, int bit, int val, int wait)

static int NCR5380_poll_politely2(struct Scsi_Host *instance,

                                  int reg1, int bit1, int val1,

                                  int reg2, int bit2, int val2, int wait)

{

	struct NCR5380_hostdata *hostdata = shost_priv(instance);

	unsigned long deadline = jiffies + wait;
@@ -482,9 +486,11 @@ static int NCR5380_poll_politely(struct Scsi_Host *instance, 
	/* Busy-wait for up to 10 ms */

	n = min(10000U, jiffies_to_usecs(wait));

	n *= hostdata->accesses_per_ms;

	n /= 1000;

	n /= 2000;

	do {

		if ((NCR5380_read(reg) & bit) == val)

		if ((NCR5380_read(reg1) & bit1) == val1)

			return 0;

		if ((NCR5380_read(reg2) & bit2) == val2)

			return 0;

		cpu_relax();

	} while (n--);
@@ -495,13 +501,22 @@ static int NCR5380_poll_politely(struct Scsi_Host *instance, 
	/* Repeatedly sleep for 1 ms until deadline */

	while (time_is_after_jiffies(deadline)) {

		schedule_timeout_uninterruptible(1);

		if ((NCR5380_read(reg) & bit) == val)

		if ((NCR5380_read(reg1) & bit1) == val1)

			return 0;

		if ((NCR5380_read(reg2) & bit2) == val2)

			return 0;

	}



	return -ETIMEDOUT;

}



static inline int NCR5380_poll_politely(struct Scsi_Host *instance,

                                        int reg, int bit, int val, int wait)

{

	return NCR5380_poll_politely2(instance, reg, bit, val,

	                                        reg, bit, val, wait);

}



#include <linux/delay.h>



#if NDEBUG
@@ -1348,7 +1363,6 @@ 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,
@@ -1378,20 +1392,18 @@ static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd) 
	 */



	local_irq_restore(flags);

	timeout = jiffies + HZ;

	while (1) {

		if (time_is_before_jiffies(timeout)) {

			NCR5380_write(MODE_REG, MR_BASE);

			shost_printk(KERN_ERR, instance,

			             "select: arbitration timeout\n");

			return -1;

		}

	err = NCR5380_poll_politely2(instance, MODE_REG, MR_ARBITRATE, 0,

	                INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS,

	                                       ICR_ARBITRATION_PROGRESS, HZ);

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

		/* Reselection interrupt */

		return -1;

	}

		if (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)

			break;

	if (err < 0) {

		NCR5380_write(MODE_REG, MR_BASE);

		shost_printk(KERN_ERR, instance,

		             "select: arbitration timeout\n");

		return -1;

	}



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

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