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atari_NCR5380: Use arbitration timeout

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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: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Finn Thain 2016-01-03 16:05:35 +11:00 committed by Martin K. Petersen
parent 80d3eb6df4
commit 55500d9b08
2 changed files with 55 additions and 58 deletions
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48
drivers/scsi/NCR5380.c
View File

@ -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);
/* 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__);
NCR5380_write(MODE_REG, MR_BASE);
NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
return -1;
}
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 chip now waits for BUS FREE phase. Then after the 800 ns
* Bus Free Delay, arbitration will begin.
*/
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;
}
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);
}
/* 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;
}

65
drivers/scsi/atari_NCR5380.c
View File

@ -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;
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__);
NCR5380_write(MODE_REG, MR_BASE);
NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
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);
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().
*
/* The chip now waits for BUS FREE phase. Then after the 800 ns
* Bus Free Delay, arbitration will begin.
*/
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;
}
if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) {
/* Reselection interrupt */
return -1;
}
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);