diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 380b4b43f3612a31292ec89a195aeca347a3d079..7afba40e350e0e30e5c23588e345f335c252222b 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -985,8 +985,6 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
 		state->flags = 0;
 		switch (cx->type) {
 			case ACPI_STATE_C1:
-			if (cx->entry_method != ACPI_CSTATE_FFH)
-				state->flags |= CPUIDLE_FLAG_TIME_INVALID;
 
 			state->enter = acpi_idle_enter_c1;
 			state->enter_dead = acpi_idle_play_dead;
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index a07e087f54b205741da6c126d0ca2144257140af..ab70f3bc44ad7a2c1ddf2454dac51f7a80e95f41 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -53,7 +53,6 @@ struct cpuidle_state {
 };
 
 /* Idle State Flags */
-#define CPUIDLE_FLAG_TIME_INVALID	(0x01) /* is residency time measurable? */
 #define CPUIDLE_FLAG_COUPLED	(0x02) /* state applies to multiple cpus */
 #define CPUIDLE_FLAG_TIMER_STOP (0x04)  /* timer is stopped on this state */
 
@@ -89,8 +88,6 @@ DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev);
 /**
  * cpuidle_get_last_residency - retrieves the last state's residency time
  * @dev: the target CPU
- *
- * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_INVALID is set
  */
 static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
 {