diff --git a/cpu/mpc85xx/cpu.c b/cpu/mpc85xx/cpu.c
index 7976cac..67e81c0 100644
--- a/cpu/mpc85xx/cpu.c
+++ b/cpu/mpc85xx/cpu.c
@@ -298,15 +298,14 @@
 #endif
 
 /*
- * Configures a UPM. Currently, the loop fields in MxMR (RLF, WLF and TLF)
- * are hardcoded as "1"."size" is the number or entries, not a sizeof.
+ * Configures a UPM. The function requires the respective MxMR to be set
+ * before calling this function. "size" is the number or entries, not a sizeof.
  */
 void upmconfig (uint upm, uint * table, uint size)
 {
 	int i, mdr, mad, old_mad = 0;
 	volatile u32 *mxmr;
 	volatile ccsr_lbc_t *lbc = (void *)(CFG_MPC85xx_LBC_ADDR);
-	int loopval = 0x00004440;
 	volatile u32 *brp,*orp;
 	volatile u8* dummy = NULL;
 	int upmmask;
@@ -334,8 +333,8 @@
 		 i++, brp += 2, orp += 2) {
 
 		/* Look for a valid BR with selected UPM */
-		if ((in_be32(brp) & (BR_V | upmmask)) == (BR_V | upmmask)) {
-			dummy = (volatile u8*)(in_be32(brp) >> BR_BA_SHIFT);
+		if ((in_be32(brp) & (BR_V | BR_MSEL)) == (BR_V | upmmask)) {
+			dummy = (volatile u8*)(in_be32(brp) & BR_BA);
 			break;
 		}
 	}
@@ -347,7 +346,7 @@
 
 	for (i = 0; i < size; i++) {
 		/* 1 */
-		out_be32(mxmr, loopval | 0x10000000 | i); /* OP_WRITE */
+		out_be32(mxmr,  (in_be32(mxmr) & 0x4fffffc0) | MxMR_OP_WARR | i);
 		/* 2 */
 		out_be32(&lbc->mdr, table[i]);
 		/* 3 */
@@ -356,11 +355,11 @@
 		*(volatile u8 *)dummy = 0;
 		/* 5 */
 		do {
-			mad = in_be32(mxmr) & 0x3f;
+			mad = in_be32(mxmr) & MxMR_MAD_MSK;
 		} while (mad <= old_mad && !(!mad && i == (size-1)));
 		old_mad = mad;
 	}
-	out_be32(mxmr, loopval); /* OP_NORMAL */
+	out_be32(mxmr, (in_be32(mxmr) & 0x4fffffc0) | MxMR_OP_NORM);
 }