ahci: qoriq: Update the default Rx watermark value

The PTC[RXWM] sets the watermark value for Rx FIFO. The default
value 0x20 might be insufficient for some hard drives. If the
watermark value is too small, a single-cycle overflow may occur
and is reported as a CRC or internal error in the PxSERR register.
Updated the value to 0x29 according to the validation test.
All LS platforms are affected.

Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/drivers/ata/ahci_qoriq.c b/drivers/ata/ahci_qoriq.c
index 4d613f8..256d911 100644
--- a/drivers/ata/ahci_qoriq.c
+++ b/drivers/ata/ahci_qoriq.c
@@ -38,7 +38,7 @@
 #define AHCI_PORT_PHY_3_CFG	0x0e081004
 #define AHCI_PORT_PHY_4_CFG	0x00480811
 #define AHCI_PORT_PHY_5_CFG	0x192c96a4
-#define AHCI_PORT_TRANS_CFG	0x08000025
+#define AHCI_PORT_TRANS_CFG	0x08000029
 #define LS1043A_PORT_PHY2	0x28184d1f
 #define LS1043A_PORT_PHY3	0x0e081509
 
@@ -169,6 +169,7 @@
 
 	case AHCI_LS2080A:
 		writel(AHCI_PORT_PHY_1_CFG, reg_base + PORT_PHY1);
+		writel(AHCI_PORT_TRANS_CFG, reg_base + PORT_TRANS);
 		break;
 	}