diff --git a/arch/tile/include/asm/thread_info.h b/arch/tile/include/asm/thread_info.h
index 7e1fef36bde6..e9c670d7a7fe 100644
--- a/arch/tile/include/asm/thread_info.h
+++ b/arch/tile/include/asm/thread_info.h
@@ -91,11 +91,6 @@ extern void smp_nap(void);
 /* Enable interrupts racelessly and nap forever: helper for cpu_idle(). */
 extern void _cpu_idle(void);
 
-/* Switch boot idle thread to a freshly-allocated stack and free old stack. */
-extern void cpu_idle_on_new_stack(struct thread_info *old_ti,
-				  unsigned long new_sp,
-				  unsigned long new_ss10);
-
 #else /* __ASSEMBLY__ */
 
 /*
diff --git a/arch/tile/kernel/entry.S b/arch/tile/kernel/entry.S
index 133c4b56a99e..c31637baff28 100644
--- a/arch/tile/kernel/entry.S
+++ b/arch/tile/kernel/entry.S
@@ -68,20 +68,6 @@ STD_ENTRY(KBacktraceIterator_init_current)
 	jrp lr   /* keep backtracer happy */
 	STD_ENDPROC(KBacktraceIterator_init_current)
 
-/*
- * Reset our stack to r1/r2 (sp and ksp0+cpu respectively), then
- * free the old stack (passed in r0) and re-invoke cpu_idle().
- * We update sp and ksp0 simultaneously to avoid backtracer warnings.
- */
-STD_ENTRY(cpu_idle_on_new_stack)
-	{
-	 move sp, r1
-	 mtspr SPR_SYSTEM_SAVE_K_0, r2
-	}
-	jal free_thread_info
-	j cpu_idle
-	STD_ENDPROC(cpu_idle_on_new_stack)
-
 /* Loop forever on a nap during SMP boot. */
 STD_ENTRY(smp_nap)
 	nap
diff --git a/arch/tile/kernel/setup.c b/arch/tile/kernel/setup.c
index 6098ccc59be2..dd87f3420390 100644
--- a/arch/tile/kernel/setup.c
+++ b/arch/tile/kernel/setup.c
@@ -29,6 +29,7 @@
 #include <linux/smp.h>
 #include <linux/timex.h>
 #include <linux/hugetlb.h>
+#include <linux/start_kernel.h>
 #include <asm/setup.h>
 #include <asm/sections.h>
 #include <asm/cacheflush.h>