Index: stand/powerpc/ofw/cas.c
===================================================================
--- stand/powerpc/ofw/cas.c
+++ stand/powerpc/ofw/cas.c
@@ -84,12 +84,15 @@
 
 /* byte 24: MMU */
 #define OV5_MMU_HPT		0
+#define OV5_MMU_RADIX		0x40
+#define OV5_MMU_EITHER		0x80
+#define OV5_MMU_DYNAMIC		0xc0
 
 /* byte 25: HPT MMU Extensions */
-#define OV5_HPT_EXT_NONE	0
+#define OV5_HPT_GTSE		0x40
 
 /* byte 26: Radix MMU Extensions */
-#define OV5_RPT_EXT_NONE	0
+#define OV5_RADIX_GTSE		0x40
 
 
 struct pvr {
@@ -163,8 +166,8 @@
 		0,	/* DRMEM_V2 */
 		OV5_INTC_XICS,
 		OV5_MMU_HPT,
-		OV5_HPT_EXT_NONE,
-		OV5_RPT_EXT_NONE
+		0,
+		OV5_RADIX_GTSE
 	}
 };
 
@@ -193,16 +196,19 @@
 int
 ppc64_cas(void)
 {
-	int rc;
+	int rc, radix_mmu = 0;
 	ihandle_t ihandle;
 	cell_t err;
+	const char *var;
 
 	/* Perform CAS only for POWER8 and later cores */
 	switch (mfpvr() & PVR_CPU_MASK) {
 		case PVR_CPU_P8:
 		case PVR_CPU_P8E:
 		case PVR_CPU_P8NVL:
+			break;
 		case PVR_CPU_P9:
+			radix_mmu = 1;
 			break;
 		default:
 			return (0);
@@ -212,6 +218,11 @@
 	if (ppc64_hv())
 		return (0);
 
+	if (radix_mmu && (var = getenv("radix_mmu")) != NULL && var[0] != '0')
+		ibm_arch_vec.vec5.data[24] = OV5_MMU_RADIX;
+	else
+		radix_mmu = 0;
+
 	ihandle = OF_open("/");
 	if (ihandle == -1) {
 		printf("cas: failed to open / node\n");
@@ -227,5 +238,6 @@
 	}
 
 	OF_close(ihandle);
+	printf("cas: selected %s MMU\n", radix_mmu ? "radix" : "hash");
 	return (rc);
 }