[PATCH] libata: improve ata_bus_probe()
Improve ata_bus_probe() such that configuration failures are handled
better. Each device is given ATA_PROBE_MAX_TRIES chances, but any
non-transient error (revalidation failure with -ENODEV, configuration
failure with -EINVAL...) disables the device directly. Any IO error
results in SATA PHY speed down and ata_set_mode() failure lowers
transfer mode. The last try always puts a device into PIO-0.
After each failure, the whole port is reset to make sure that the
controller and all the devices are in a known and stable state. The
reset also applies SATA SPD configuration if necessary.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 68fa64d..33b5bff 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -1370,11 +1370,18 @@
static int ata_bus_probe(struct ata_port *ap)
{
unsigned int classes[ATA_MAX_DEVICES];
- int i, rc, found = 0;
+ int tries[ATA_MAX_DEVICES];
+ int i, rc, down_xfermask;
struct ata_device *dev;
ata_port_probe(ap);
+ for (i = 0; i < ATA_MAX_DEVICES; i++)
+ tries[i] = ATA_PROBE_MAX_TRIES;
+
+ retry:
+ down_xfermask = 0;
+
/* reset and determine device classes */
for (i = 0; i < ATA_MAX_DEVICES; i++)
classes[i] = ATA_DEV_UNKNOWN;
@@ -1404,21 +1411,23 @@
dev = &ap->device[i];
dev->class = classes[i];
+ if (!tries[i]) {
+ ata_down_xfermask_limit(ap, dev, 1);
+ ata_dev_disable(ap, dev);
+ }
+
if (!ata_dev_enabled(dev))
continue;
- WARN_ON(dev->id != NULL);
- if (ata_dev_read_id(ap, dev, &dev->class, 1, &dev->id)) {
- dev->class = ATA_DEV_NONE;
- continue;
- }
+ kfree(dev->id);
+ dev->id = NULL;
+ rc = ata_dev_read_id(ap, dev, &dev->class, 1, &dev->id);
+ if (rc)
+ goto fail;
- if (ata_dev_configure(ap, dev, 1)) {
- ata_dev_disable(ap, dev);
- continue;
- }
-
- found = 1;
+ rc = ata_dev_configure(ap, dev, 1);
+ if (rc)
+ goto fail;
}
/* configure transfer mode */
@@ -1427,12 +1436,18 @@
* return error code and failing device on failure as
* ata_set_mode() does.
*/
- if (found)
- ap->ops->set_mode(ap);
+ for (i = 0; i < ATA_MAX_DEVICES; i++)
+ if (ata_dev_enabled(&ap->device[i])) {
+ ap->ops->set_mode(ap);
+ break;
+ }
rc = 0;
} else {
- while (ata_set_mode(ap, &dev))
- ata_dev_disable(ap, dev);
+ rc = ata_set_mode(ap, &dev);
+ if (rc) {
+ down_xfermask = 1;
+ goto fail;
+ }
}
for (i = 0; i < ATA_MAX_DEVICES; i++)
@@ -1443,6 +1458,24 @@
ata_port_disable(ap);
ap->ops->port_disable(ap);
return -ENODEV;
+
+ fail:
+ switch (rc) {
+ case -EINVAL:
+ case -ENODEV:
+ tries[dev->devno] = 0;
+ break;
+ case -EIO:
+ ata_down_sata_spd_limit(ap);
+ /* fall through */
+ default:
+ tries[dev->devno]--;
+ if (down_xfermask &&
+ ata_down_xfermask_limit(ap, dev, tries[dev->devno] == 1))
+ tries[dev->devno] = 0;
+ }
+
+ goto retry;
}
/**