diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
index 23ffafd927a1..ca0976456a6b 100644
--- a/arch/x86/include/asm/acpi.h
+++ b/arch/x86/include/asm/acpi.h
@@ -13,7 +13,6 @@
 #include <asm/processor.h>
 #include <asm/mmu.h>
 #include <asm/mpspec.h>
-#include <asm/realmode.h>
 #include <asm/x86_init.h>
 
 #ifdef CONFIG_ACPI_APEI
@@ -62,10 +61,7 @@ static inline void acpi_disable_pci(void)
 extern int (*acpi_suspend_lowlevel)(void);
 
 /* Physical address to resume after wakeup */
-static inline unsigned long acpi_get_wakeup_address(void)
-{
-	return ((unsigned long)(real_mode_header->wakeup_start));
-}
+unsigned long acpi_get_wakeup_address(void);
 
 /*
  * Check if the CPU can handle C2 and deeper
diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
index ca13851f0570..26b7256f590f 100644
--- a/arch/x86/kernel/acpi/sleep.c
+++ b/arch/x86/kernel/acpi/sleep.c
@@ -26,6 +26,17 @@ unsigned long acpi_realmode_flags;
 static char temp_stack[4096];
 #endif
 
+/**
+ * acpi_get_wakeup_address - provide physical address for S3 wakeup
+ *
+ * Returns the physical address where the kernel should be resumed after the
+ * system awakes from S3, e.g. for programming into the firmware waking vector.
+ */
+unsigned long acpi_get_wakeup_address(void)
+{
+	return ((unsigned long)(real_mode_header->wakeup_start));
+}
+
 /**
  * x86_acpi_enter_sleep_state - enter sleep state
  * @state: Sleep state to enter.