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 --- drivers/scsi/NCR5380.c | 44 ++++++++++++++++++--------------- drivers/scsi/atari_NCR5380.c | 57 ++++++++++++++++++------------------------- 2 files changed, 49 insertions(+), 52 deletions(-) Index: linux/drivers/scsi/atari_NCR5380.c =================================================================== --- linux.orig/drivers/scsi/atari_NCR5380.c 2015-12-06 12:30:21.000000000 +1100 +++ linux/drivers/scsi/atari_NCR5380.c 2015-12-06 12:30:23.000000000 +1100 @@ -1407,6 +1407,7 @@ static int NCR5380_select(struct Scsi_Ho 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, @@ -1431,42 +1432,28 @@ static int NCR5380_select(struct Scsi_Ho NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); NCR5380_write(MODE_REG, MR_ARBITRATE); - local_irq_restore(flags); + /* The chip now waits for BUS FREE phase. Then after the 800 ns + * Bus Free Delay, arbitration will begin. + */ - /* 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__); + 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; } + if (!(NCR5380_read(MODE_REG) & MR_ARBITRATE)) { + /* Reselection interrupt */ + return -1; + } + if (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) + break; } -#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 SCSI-2 arbitration delay is 2.4 us */ udelay(3); /* Check for lost arbitration */ @@ -1629,8 +1616,14 @@ static int NCR5380_select(struct Scsi_Ho */ /* 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); Index: linux/drivers/scsi/NCR5380.c =================================================================== --- linux.orig/drivers/scsi/NCR5380.c 2015-12-06 12:30:21.000000000 +1100 +++ linux/drivers/scsi/NCR5380.c 2015-12-06 12:30:23.000000000 +1100 @@ -1078,6 +1078,7 @@ static int NCR5380_select(struct Scsi_Ho 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); @@ -1096,28 +1097,31 @@ static int NCR5380_select(struct Scsi_Ho 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__); - NCR5380_write(MODE_REG, MR_BASE); - NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); - return -1; + 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); } - 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 */ @@ -1265,9 +1269,9 @@ static int NCR5380_select(struct Scsi_Ho 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; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/