diff --git a/drivers/block/ahci.c b/drivers/block/ahci.c
index 4df8046..dce99ad 100644
--- a/drivers/block/ahci.c
+++ b/drivers/block/ahci.c
@@ -129,6 +129,14 @@
 	return 1;
 }
 
+#ifdef CONFIG_SUNXI_AHCI
+/* The sunxi AHCI controller requires this undocumented setup */
+static void sunxi_dma_init(volatile u8 *port_mmio)
+{
+	clrsetbits_le32(port_mmio + PORT_P0DMACR, 0x0000ff00, 0x00004400);
+}
+#endif
+
 static int ahci_host_init(struct ahci_probe_ent *probe_ent)
 {
 #ifndef CONFIG_SCSI_AHCI_PLAT
@@ -213,6 +221,10 @@
 			msleep(500);
 		}
 
+#ifdef CONFIG_SUNXI_AHCI
+		sunxi_dma_init(port_mmio);
+#endif
+
 		/* Add the spinup command to whatever mode bits may
 		 * already be on in the command register.
 		 */
@@ -545,6 +557,10 @@
 
 	writel_with_flush(pp->rx_fis, port_mmio + PORT_FIS_ADDR);
 
+#ifdef CONFIG_SUNXI_AHCI
+	sunxi_dma_init(port_mmio);
+#endif
+
 	writel_with_flush(PORT_CMD_ICC_ACTIVE | PORT_CMD_FIS_RX |
 			  PORT_CMD_POWER_ON | PORT_CMD_SPIN_UP |
 			  PORT_CMD_START, port_mmio + PORT_CMD);