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: 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>
diff --git a/drivers/scsi/atari_NCR5380.c b/drivers/scsi/atari_NCR5380.c
index a3c0968..a92e4a5 100644
--- a/drivers/scsi/atari_NCR5380.c
+++ b/drivers/scsi/atari_NCR5380.c
@@ -1412,6 +1412,7 @@
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 @@
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 @@
*/
/* 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);