ata: Fixes related to APM X-Gene SATA host controller driver.

index 77c89bf..03b6b0f 100644
@@ -67,6 +67,9 @@
 #define PORTAXICFG			0x000000bc
 #define PORTAXICFG_OUTTRANS_SET(dst, src) \
 		(((dst) & ~0x00f00000) | (((u32)(src) << 0x14) & 0x00f00000))
+#define PORTRANSCFG			0x000000c8
+#define PORTRANSCFG_RXWM_SET(dst, src)		\
+		(((dst) & ~0x0000007f) | (((u32)(src)) & 0x0000007f))
 
 /* SATA host controller AXI CSR */
 #define INT_SLV_TMOMASK			0x00000010

@@ -176,6 +179,10 @@ static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel)
 	val = PORTAXICFG_OUTTRANS_SET(val, 0xe); /* Set outstanding */
 	writel(val, mmio + PORTAXICFG);
 	readl(mmio + PORTAXICFG); /* Force a barrier */
+	/* Set the watermark threshold of the receive FIFO */
+	val = readl(mmio + PORTRANSCFG);
+	val = PORTRANSCFG_RXWM_SET(val, 0x30);
+	writel(val, mmio + PORTRANSCFG);
 }
 
 /**

index 03b6b0f..cc26342 100644
@@ -78,6 +78,9 @@
 #define CFG_MEM_RAM_SHUTDOWN		0x00000070
 #define BLOCK_MEM_RDY			0x00000074
 
+/* Max retry for link down */
+#define MAX_LINK_DOWN_RETRY 3
+
 struct xgene_ahci_context {
 	struct ahci_host_priv *hpriv;
 	struct device *dev;

@@ -234,15 +237,20 @@ static int xgene_ahci_do_hardreset(struct ata_link *link,
 	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
 	void __iomem *port_mmio = ahci_port_base(ap);
 	struct ata_taskfile tf;
+	int link_down_retry = 0;
 	int rc;
 	u32 val;
 
-	/* clear D2H reception area to properly wait for D2H FIS */
-	ata_tf_init(link->device, &tf);
-	tf.command = ATA_BUSY;
-	ata_tf_to_fis(&tf, 0, 0, d2h_fis);
-	rc = sata_link_hardreset(link, timing, deadline, online,
+	do {
+		/* clear D2H reception area to properly wait for D2H FIS */
+		ata_tf_init(link->device, &tf);
+		tf.command = ATA_BUSY;
+		ata_tf_to_fis(&tf, 0, 0, d2h_fis);
+		rc = sata_link_hardreset(link, timing, deadline, online,
 				 ahci_check_ready);
+		if (*online)
+			break;
+	} while (link_down_retry++ < MAX_LINK_DOWN_RETRY);
 
 	val = readl(port_mmio + PORT_SCR_ERR);
 	if (val & (SERR_DISPARITY | SERR_10B_8B_ERR))