ahci: qoriq: enable snoopable sata read and write

By default the SATA IP on the qoriq SoCs does not generating
coherent/snoopable transactions.  This patch enable it in the
sata axicc register.
In addition, the dma-coherent property must be set on the
SATA controller nodes.

Signed-off-by: Tang Yuantian <yuantian.tang@nxp.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/drivers/ata/ahci_qoriq.c b/drivers/ata/ahci_qoriq.c
index ed357a1..925c4b6 100644
--- a/drivers/ata/ahci_qoriq.c
+++ b/drivers/ata/ahci_qoriq.c
@@ -30,17 +30,20 @@
 #define PORT_PHY3	0xB0
 #define PORT_PHY4	0xB4
 #define PORT_PHY5	0xB8
+#define PORT_AXICC	0xBC
 #define PORT_TRANS	0xC8
 
 /* port register default value */
 #define AHCI_PORT_PHY_1_CFG	0xa003fffe
 #define AHCI_PORT_TRANS_CFG	0x08000029
+#define AHCI_PORT_AXICC_CFG	0x3fffffff
 
 /* for ls1021a */
 #define LS1021A_PORT_PHY2	0x28183414
 #define LS1021A_PORT_PHY3	0x0e080e06
 #define LS1021A_PORT_PHY4	0x064a080b
 #define LS1021A_PORT_PHY5	0x2aa86470
+#define LS1021A_AXICC_ADDR	0xC0
 
 #define SATA_ECC_DISABLE	0x00020000
 
@@ -158,16 +161,19 @@
 		writel(LS1021A_PORT_PHY4, reg_base + PORT_PHY4);
 		writel(LS1021A_PORT_PHY5, reg_base + PORT_PHY5);
 		writel(AHCI_PORT_TRANS_CFG, reg_base + PORT_TRANS);
+		writel(AHCI_PORT_AXICC_CFG, reg_base + LS1021A_AXICC_ADDR);
 		break;
 
 	case AHCI_LS1043A:
 		writel(AHCI_PORT_PHY_1_CFG, reg_base + PORT_PHY1);
 		writel(AHCI_PORT_TRANS_CFG, reg_base + PORT_TRANS);
+		writel(AHCI_PORT_AXICC_CFG, reg_base + PORT_AXICC);
 		break;
 
 	case AHCI_LS2080A:
 		writel(AHCI_PORT_PHY_1_CFG, reg_base + PORT_PHY1);
 		writel(AHCI_PORT_TRANS_CFG, reg_base + PORT_TRANS);
+		writel(AHCI_PORT_AXICC_CFG, reg_base + PORT_AXICC);
 		break;
 	}