From: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>
Add a new flag CPUIDLE_FLAG_S2IDLE to allow c-state to be found as
deepest state for s2idle only, so that users can add a new c-state
for using s2idle and don't worry disturbing other use cases such as
play_idle() which probably don't want to enter into so much deep
idle state since devices are not suspended for that kind of cases.
Signed-off-by: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>
---
drivers/cpuidle/cpuidle.c | 3 ++-
drivers/cpuidle/dt_idle_states.c | 3 +++
include/linux/cpuidle.h | 1 +
3 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index de81298051b3..bb61f0c271d2 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -89,7 +89,8 @@ static int find_deepest_state(struct cpuidle_driver *drv,
s->exit_latency_ns <= latency_req ||
s->exit_latency_ns > max_latency_ns ||
(s->flags & forbidden_flags) ||
- (s2idle && !s->enter_s2idle))
+ (s2idle && !s->enter_s2idle) ||
+ (!s2idle && (s->flags & CPUIDLE_FLAG_S2ILDE)))
continue;
latency_req = s->exit_latency_ns;
diff --git a/drivers/cpuidle/dt_idle_states.c b/drivers/cpuidle/dt_idle_states.c
index 252f2a9686a6..530db2726c05 100644
--- a/drivers/cpuidle/dt_idle_states.c
+++ b/drivers/cpuidle/dt_idle_states.c
@@ -80,6 +80,9 @@ static int init_state_node(struct cpuidle_state *idle_state,
idle_state->flags = 0;
if (of_property_read_bool(state_node, "local-timer-stop"))
idle_state->flags |= CPUIDLE_FLAG_TIMER_STOP;
+
+ if (of_property_read_bool(state_node, "for-s2idle-only"))
+ idle_state->flags |= CPUIDLE_FLAG_S2ILDE;
/*
* TODO:
* replace with kstrdup and pointer assignment when name
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index ec2ef63771f0..08da701f74cd 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -78,6 +78,7 @@ struct cpuidle_state {
#define CPUIDLE_FLAG_TIMER_STOP BIT(2) /* timer is stopped on this state */
#define CPUIDLE_FLAG_UNUSABLE BIT(3) /* avoid using this state */
#define CPUIDLE_FLAG_OFF BIT(4) /* disable this state by default */
+#define CPUIDLE_FLAG_S2ILDE BIT(5) /* state is used for s2idle only */
struct cpuidle_device_kobj;
struct cpuidle_state_kobj;
--
2.20.1
