diff --git a/[refs] b/[refs]
index 3b6dae4353b7..9d1c07d4a262 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ef143d577ba98c8a53aee9aa60e7d1f07c32fd7a
+refs/heads/master: afe3cc51ba4be6b25b721c40f178ea4157751161
diff --git a/trunk/drivers/ata/libata-core.c b/trunk/drivers/ata/libata-core.c
index e7937166a8ba..bf8d3b8c171d 100644
--- a/trunk/drivers/ata/libata-core.c
+++ b/trunk/drivers/ata/libata-core.c
@@ -6317,7 +6317,8 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
 		/* init sata_spd_limit to the current value */
 		if (sata_scr_read(ap, SCR_CONTROL, &scontrol) == 0) {
 			int spd = (scontrol >> 4) & 0xf;
-			ap->hw_sata_spd_limit &= (1 << spd) - 1;
+			if (spd)
+				ap->hw_sata_spd_limit &= (1 << spd) - 1;
 		}
 		ap->sata_spd_limit = ap->hw_sata_spd_limit;