diff --git a/arch/ppc/kernel/head_44x.S b/arch/ppc/kernel/head_44x.S
index 8b49679fad54..677c571aa276 100644
--- a/arch/ppc/kernel/head_44x.S
+++ b/arch/ppc/kernel/head_44x.S
@@ -190,8 +190,8 @@ skpinv:	addi	r4,r4,1				/* Increment */
 
 	/* xlat fields */
 	lis	r4,UART0_PHYS_IO_BASE@h		/* RPN depends on SoC */
-#ifndef CONFIG_440EP
-	ori	r4,r4,0x0001		/* ERPN is 1 for second 4GB page */
+#ifdef UART0_PHYS_ERPN
+	ori	r4,r4,UART0_PHYS_ERPN		/* Add ERPN if above 4GB */
 #endif
 
 	/* attrib fields */
diff --git a/include/asm-ppc/ibm44x.h b/include/asm-ppc/ibm44x.h
index e5374be86aef..197a9ff23dd5 100644
--- a/include/asm-ppc/ibm44x.h
+++ b/include/asm-ppc/ibm44x.h
@@ -34,12 +34,17 @@
 /* Lowest TLB slot consumed by the default pinned TLBs */
 #define PPC44x_LOW_SLOT		63
 
-/* LS 32-bits of UART0 physical address location for early serial text debug */
+/*
+ * Least significant 32-bits and extended real page number (ERPN) of
+ * UART0 physical address location for early serial text debug
+ */
 #if defined(CONFIG_440SP)
+#define UART0_PHYS_ERPN		1
 #define UART0_PHYS_IO_BASE	0xf0000200
 #elif defined(CONFIG_440EP)
 #define UART0_PHYS_IO_BASE	0xe0000000
 #else
+#define UART0_PHYS_ERPN		1
 #define UART0_PHYS_IO_BASE	0x40000200
 #endif