diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h
index f82b447bd34f..b58ea9338f4e 100644
--- a/arch/arm64/include/asm/smp.h
+++ b/arch/arm64/include/asm/smp.h
@@ -95,14 +95,7 @@ extern void secondary_entry(void);
 extern void arch_send_call_function_single_ipi(int cpu);
 extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
 
-#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
 extern void arch_send_wakeup_ipi_mask(const struct cpumask *mask);
-#else
-static inline void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
-{
-	BUILD_BUG();
-}
-#endif
 
 extern int __cpu_disable(void);
 
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 9a638ba75954..f017bbf10996 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -794,12 +794,10 @@ void arch_send_call_function_single_ipi(int cpu)
 	smp_cross_call_common(cpumask_of(cpu), IPI_CALL_FUNC);
 }
 
-#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
 void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
 {
 	smp_cross_call_common(mask, IPI_WAKEUP);
 }
-#endif
 
 #ifdef CONFIG_IRQ_WORK
 void arch_irq_work_raise(void)
@@ -917,13 +915,8 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
 		break;
 #endif
 
-#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
 	case IPI_WAKEUP:
-		WARN_ONCE(!acpi_parking_protocol_valid(cpu),
-			  "CPU%u: Wake-up IPI outside the ACPI parking protocol\n",
-			  cpu);
 		break;
-#endif
 
 	default:
 		pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr);