libata: improve probe failure handling
* Move forcing device to PIO0 on device disable into
ata_dev_disable(). This makes both old and new EHs act the same
way.
* Speed down only PIO mode on probe failure. All commands used during
probing are PIO commands. There's no point in speeding down DMA.
* Retry at least once after -ENODEV. Some devices report garbled
IDENTIFY data after certain events. This shouldn't cause device
detach and re-attach.
* Rearrange EH failure path for simplicity.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 249d487..24c6505 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -600,6 +600,8 @@
{
if (ata_dev_enabled(dev) && ata_msg_drv(dev->ap)) {
ata_dev_printk(dev, KERN_WARNING, "disabled\n");
+ ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 |
+ ATA_DNXFER_QUIET);
dev->class++;
}
}
@@ -1778,9 +1780,8 @@
{
unsigned int classes[ATA_MAX_DEVICES];
int tries[ATA_MAX_DEVICES];
- int i, rc, down_xfermask;
+ int i, rc;
struct ata_device *dev;
- int dnxfer_sel;
ata_port_probe(ap);
@@ -1788,8 +1789,6 @@
tries[i] = ATA_PROBE_MAX_TRIES;
retry:
- down_xfermask = 0;
-
/* reset and determine device classes */
ap->ops->phy_reset(ap);
@@ -1837,10 +1836,8 @@
/* configure transfer mode */
rc = ata_set_mode(ap, &dev);
- if (rc) {
- down_xfermask = 1;
+ if (rc)
goto fail;
- }
for (i = 0; i < ATA_MAX_DEVICES; i++)
if (ata_dev_enabled(&ap->device[i]))
@@ -1852,27 +1849,29 @@
return -ENODEV;
fail:
+ tries[dev->devno]--;
+
switch (rc) {
case -EINVAL:
- case -ENODEV:
+ /* eeek, something went very wrong, give up */
tries[dev->devno] = 0;
break;
+
+ case -ENODEV:
+ /* give it just one more chance */
+ tries[dev->devno] = min(tries[dev->devno], 1);
case -EIO:
- sata_down_spd_limit(ap);
- /* fall through */
- default:
- tries[dev->devno]--;
- dnxfer_sel = ATA_DNXFER_ANY;
- if (tries[dev->devno] == 1)
- dnxfer_sel = ATA_DNXFER_FORCE_PIO0;
- if (down_xfermask && ata_down_xfermask_limit(dev, dnxfer_sel))
- tries[dev->devno] = 0;
+ if (tries[dev->devno] == 1) {
+ /* This is the last chance, better to slow
+ * down than lose it.
+ */
+ sata_down_spd_limit(ap);
+ ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
+ }
}
- if (!tries[dev->devno]) {
- ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0);
+ if (!tries[dev->devno])
ata_dev_disable(dev);
- }
goto retry;
}