Index: sys/arm/mv/mv_common.c
===================================================================
--- sys/arm/mv/mv_common.c
+++ sys/arm/mv/mv_common.c
@@ -128,6 +128,7 @@
 static int cpu_wins_no = 0;
 static int eth_port = 0;
 static int usb_port = 0;
+static boolean_t plat_dma_coherent = false;
 
 static struct decode_win cpu_win_tbl[MAX_CPU_WIN];
 
@@ -573,6 +574,7 @@
 {
 	uint32_t dev, rev;
 	int mask, err;
+	phandle_t node;
 
 	mask = 0;
 	TUNABLE_INT_FETCH("hw.pm-disable-mask", &mask);
@@ -587,6 +589,11 @@
 	/* Retrieve our ID: some windows facilities vary between SoC models */
 	soc_id(&dev, &rev);
 
+	/* Retrieve information about DMA coherency from device tree */
+	node = OF_finddevice("/soc");
+	if ((node > 0) && OF_hasprop(node, "dma-coherent"))
+		plat_dma_coherent = true;
+
 #ifdef SOC_MV_ARMADAXP
 	if ((err = decode_win_sdram_fixup()) != 0)
 		return(err);
@@ -1064,7 +1071,7 @@
 uint32_t
 ddr_attr(int i)
 {
-	uint32_t dev, rev;
+	uint32_t dev, rev, attr;
 
 	soc_id(&dev, &rev);
 	if (dev == MV_DEV_88RC8180)
@@ -1072,10 +1079,14 @@
 	if (dev == MV_DEV_88F6781)
 		return (0);
 
-	return (i == 0 ? 0xe :
+	attr = (i == 0 ? 0xe :
 	    (i == 1 ? 0xd :
 	    (i == 2 ? 0xb :
 	    (i == 3 ? 0x7 : 0xff))));
+	if (plat_dma_coherent)
+		attr |= 0x10;
+
+	return (attr);
 }
 
 uint32_t