diff --git a/arch/arm/include/debug/efm32.S b/arch/arm/include/debug/efm32.S
index 2265a199280c..660fa1e4b77b 100644
--- a/arch/arm/include/debug/efm32.S
+++ b/arch/arm/include/debug/efm32.S
@@ -16,7 +16,7 @@
 
 #define	UARTn_TXDATA		0x0034
 
-		.macro	addruart, rx, tmp
+		.macro	addruart, rx, tmp, tmp2
 		ldr	\rx, =(CONFIG_DEBUG_UART_PHYS)
 
 		/*
diff --git a/arch/arm/kernel/debug.S b/arch/arm/kernel/debug.S
index 78c91b5f97d4..ea9646cc2a0e 100644
--- a/arch/arm/kernel/debug.S
+++ b/arch/arm/kernel/debug.S
@@ -35,7 +35,7 @@
 
 #else /* !CONFIG_MMU */
 		.macro	addruart_current, rx, tmp1, tmp2
-		addruart	\rx, \tmp1
+		addruart	\rx, \tmp1, \tmp2
 		.endm
 
 #endif /* CONFIG_MMU */