diff --git a/cpu/ppc4xx/start.S b/cpu/ppc4xx/start.S
index ac96fc28f7..582c781cac 100644
--- a/cpu/ppc4xx/start.S
+++ b/cpu/ppc4xx/start.S
@@ -2021,6 +2021,7 @@ pci_wait:
 ! Output r3 = none
 !-----------------------------------------------------------------------------
 */
+	.globl	pll_write
 pll_write:
 	mfdcr  r5, CPC0_UCR
 	andis. r5,r5,0xFFFF