libata: use longer 0xff wait if parallel scan is enabled
There are some SATA devices which take relatively long to get out of
0xff status after reset. In libata, this timeout is determined by
ATA_TMOUT_FF_WAIT. Quantum GoVault is the worst requring about 2s for
reliable detection. However, because 2s 0xff timeout can introduce
rather long spurious delay during boot, libata has been compromising
at the next longest timeout of 800ms for HHD424020F7SV00 iVDR drive.
Now that parallel scan is in place for common drivers, libata can
afford 2s 0xff timeout. Use 2s 0xff timeout if parallel scan is
enabled.
Please note that the chance of spurious wait is pretty slim w/ working
SCR access so this will only affect SATA controllers w/o SCR access
which isn't too common these days.
Please read the following thread for more information on the GoVault
drive.
http://thread.gmane.org/gmane.linux.ide/14545/focus=14663
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 4fa748e..242eb26 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -256,12 +256,13 @@
ATA_TMOUT_INTERNAL_QUICK = 5000,
ATA_TMOUT_MAX_PARK = 30000,
- /* FIXME: GoVault needs 2s but we can't afford that without
- * parallel probing. 800ms is enough for iVDR disk
- * HHD424020F7SV00. Increase to 2secs when parallel probing
- * is in place.
+ /*
+ * GoVault needs 2s and iVDR disk HHD424020F7SV00 800ms. 2s
+ * is too much without parallel probing. Use 2s if parallel
+ * probing is available, 800ms otherwise.
*/
- ATA_TMOUT_FF_WAIT = 800,
+ ATA_TMOUT_FF_WAIT_LONG = 2000,
+ ATA_TMOUT_FF_WAIT = 800,
/* Spec mandates to wait for ">= 2ms" before checking status
* after reset. We wait 150ms, because that was the magic