diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
index 379ee152..10d3fda8 100644
--- a/arch/arm64/kernel/psci.c
+++ b/arch/arm64/kernel/psci.c
@@ -100,9 +100,14 @@ static u32 psci_power_state_pack(struct psci_power_state state)
  * The following two functions are invoked via the invoke_psci_fn pointer
  * and will not be inlined, allowing us to piggyback on the AAPCS.
  */
-static noinline int __invoke_psci_fn_hvc(u64 function_id, u64 arg0, u64 arg1,
-					 u64 arg2)
-{
+static noinline int __invoke_psci_fn_hvc(u64 _function_id, u64 _arg0,
+					 u64 _arg1, u64 _arg2)
+ {
+	register u64 function_id asm("x0") = _function_id;
+	register u64 arg0 asm("x1") = _arg0;
+	register u64 arg1 asm("x2") = _arg1;
+	register u64 arg2 asm("x3") = _arg2;
+
 	asm volatile(
 			__asmeq("%0", "x0")
 			__asmeq("%1", "x1")
@@ -115,9 +120,14 @@ static noinline int __invoke_psci_fn_hvc(u64 function_id, u64 arg0, u64 arg1,
 	return function_id;
 }
 
-static noinline int __invoke_psci_fn_smc(u64 function_id, u64 arg0, u64 arg1,
-					 u64 arg2)
-{
+static noinline int __invoke_psci_fn_smc(u64 _function_id, u64 _arg0,
+					 u64 _arg1, u64 _arg2)
+ {
+	register u64 function_id asm("x0") = _function_id;
+	register u64 arg0 asm("x1") = _arg0;
+	register u64 arg1 asm("x2") = _arg1;
+	register u64 arg2 asm("x3") = _arg2;
+
 	asm volatile(
 			__asmeq("%0", "x0")
 			__asmeq("%1", "x1")