9 files changed, 82 insertions, 66 deletions

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 5c8aa9cf62d7..df38e81cc672 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -48,6 +48,8 @@
 #define _COMPONENT              ACPI_PROCESSOR_COMPONENT
 ACPI_MODULE_NAME("processor_idle");
 
+#define ACPI_IDLE_STATE_START   (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX) ? 1 : 0)
+
 static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER;
 module_param(max_cstate, uint, 0000);
 static unsigned int nocst __read_mostly;
@@ -761,7 +763,7 @@ static int acpi_idle_enter(struct cpuidle_device *dev,
 
         if (cx->type != ACPI_STATE_C1) {
                 if (acpi_idle_fallback_to_c1(pr) && num_online_cpus() > 1) {
-                        index = CPUIDLE_DRIVER_STATE_START;
+                        index = ACPI_IDLE_STATE_START;
                         cx = per_cpu(acpi_cstate[index], dev->cpu);
                 } else if (cx->type == ACPI_STATE_C3 && pr->flags.bm_check) {
                         if (cx->bm_sts_skip || !acpi_idle_bm_check()) {
@@ -813,7 +815,7 @@ static void acpi_idle_enter_freeze(struct cpuidle_device *dev,
 static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
                                            struct cpuidle_device *dev)
 {
-        int i, count = CPUIDLE_DRIVER_STATE_START;
+        int i, count = ACPI_IDLE_STATE_START;
         struct acpi_processor_cx *cx;
 
         if (max_cstate == 0)
@@ -840,7 +842,7 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
 
 static int acpi_processor_setup_cstates(struct acpi_processor *pr)
 {
-        int i, count = CPUIDLE_DRIVER_STATE_START;
+        int i, count;
         struct acpi_processor_cx *cx;
         struct cpuidle_state *state;
         struct cpuidle_driver *drv = &acpi_idle_driver;
@@ -848,6 +850,13 @@ static int acpi_processor_setup_cstates(struct acpi_processor *pr)
         if (max_cstate == 0)
                 max_cstate = 1;
 
+        if (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX)) {
+                cpuidle_poll_state_init(drv);
+                count = 1;
+        } else {
+                count = 0;
+        }
+
         for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
                 cx = &pr->power.states[i];
 
@@ -1291,7 +1300,7 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
                 return -EINVAL;
 
         drv->safe_state_index = -1;
-        for (i = CPUIDLE_DRIVER_STATE_START; i < CPUIDLE_STATE_MAX; i++) {
+        for (i = ACPI_IDLE_STATE_START; i < CPUIDLE_STATE_MAX; i++) {
                 drv->states[i].name[0] = '\0';
                 drv->states[i].desc[0] = '\0';
         }
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index 3ba81b1dffad..0b67a05a7aae 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -5,6 +5,7 @@
 obj-y += cpuidle.o driver.o governor.o sysfs.o governors/
 obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o
 obj-$(CONFIG_DT_IDLE_STATES)              += dt_idle_states.o
+obj-$(CONFIG_ARCH_HAS_CPU_RELAX)          += poll_state.o
 
 ##################################################################################
 # ARM SoC drivers
diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index e53fb861beb0..dc32f34e68d9 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -179,36 +179,6 @@ static void __cpuidle_driver_init(struct cpuidle_driver *drv)
         }
 }
 
-#ifdef CONFIG_ARCH_HAS_CPU_RELAX
-static int __cpuidle poll_idle(struct cpuidle_device *dev,
-                               struct cpuidle_driver *drv, int index)
-{
-        local_irq_enable();
-        if (!current_set_polling_and_test()) {
-                while (!need_resched())
-                        cpu_relax();
-        }
-        current_clr_polling();
-
-        return index;
-}
-
-static void poll_idle_init(struct cpuidle_driver *drv)
-{
-        struct cpuidle_state *state = &drv->states[0];
-
-        snprintf(state->name, CPUIDLE_NAME_LEN, "POLL");
-        snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
-        state->exit_latency = 0;
-        state->target_residency = 0;
-        state->power_usage = -1;
-        state->enter = poll_idle;
-        state->disabled = false;
-}
-#else
-static void poll_idle_init(struct cpuidle_driver *drv) {}
-#endif /* !CONFIG_ARCH_HAS_CPU_RELAX */
-
 /**
  * __cpuidle_register_driver: register the driver
  * @drv: a valid pointer to a struct cpuidle_driver
@@ -246,8 +216,6 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv)
                 on_each_cpu_mask(drv->cpumask, cpuidle_setup_broadcast_timer,
                                  (void *)1, 1);
 
-        poll_idle_init(drv);
-
         return 0;
 }
 
diff --git a/drivers/cpuidle/dt_idle_states.c b/drivers/cpuidle/dt_idle_states.c
index ae8eb0359889..bafd4dbf55d4 100644
--- a/drivers/cpuidle/dt_idle_states.c
+++ b/drivers/cpuidle/dt_idle_states.c
@@ -53,16 +53,16 @@ static int init_state_node(struct cpuidle_state *idle_state,
                 err = of_property_read_u32(state_node, "entry-latency-us",
                                            &entry_latency);
                 if (err) {
-                        pr_debug(" * %s missing entry-latency-us property\n",
-                                 state_node->full_name);
+                        pr_debug(" * %pOF missing entry-latency-us property\n",
+                                 state_node);
                         return -EINVAL;
                 }
 
                 err = of_property_read_u32(state_node, "exit-latency-us",
                                            &exit_latency);
                 if (err) {
-                        pr_debug(" * %s missing exit-latency-us property\n",
-                                 state_node->full_name);
+                        pr_debug(" * %pOF missing exit-latency-us property\n",
+                                 state_node);
                         return -EINVAL;
                 }
                 /*
@@ -75,8 +75,8 @@ static int init_state_node(struct cpuidle_state *idle_state,
         err = of_property_read_u32(state_node, "min-residency-us",
                                    &idle_state->target_residency);
         if (err) {
-                pr_debug(" * %s missing min-residency-us property\n",
-                             state_node->full_name);
+                pr_debug(" * %pOF missing min-residency-us property\n",
+                             state_node);
                 return -EINVAL;
         }
 
@@ -186,8 +186,8 @@ int dt_init_idle_driver(struct cpuidle_driver *drv,
                 }
 
                 if (!idle_state_valid(state_node, i, cpumask)) {
-                        pr_warn("%s idle state not valid, bailing out\n",
-                                state_node->full_name);
+                        pr_warn("%pOF idle state not valid, bailing out\n",
+                                state_node);
                         err = -EINVAL;
                         break;
                 }
@@ -200,8 +200,8 @@ int dt_init_idle_driver(struct cpuidle_driver *drv,
                 idle_state = &drv->states[state_idx++];
                 err = init_state_node(idle_state, matches, state_node);
                 if (err) {
-                        pr_err("Parsing idle state node %s failed with err %d\n",
-                               state_node->full_name, err);
+                        pr_err("Parsing idle state node %pOF failed with err %d\n",
+                               state_node, err);
                         err = -EINVAL;
                         break;
                 }
diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c
index ac321f09e717..ce1a2ffffb2a 100644
--- a/drivers/cpuidle/governors/ladder.c
+++ b/drivers/cpuidle/governors/ladder.c
@@ -69,6 +69,7 @@ static int ladder_select_state(struct cpuidle_driver *drv,
         struct ladder_device *ldev = this_cpu_ptr(&ladder_devices);
         struct ladder_device_state *last_state;
         int last_residency, last_idx = ldev->last_state_idx;
+        int first_idx = drv->states[0].flags & CPUIDLE_FLAG_POLLING ? 1 : 0;
         int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY);
 
         /* Special case when user has set very strict latency requirement */
@@ -96,13 +97,13 @@ static int ladder_select_state(struct cpuidle_driver *drv,
         }
 
         /* consider demotion */
-        if (last_idx > CPUIDLE_DRIVER_STATE_START &&
+        if (last_idx > first_idx &&
             (drv->states[last_idx].disabled ||
             dev->states_usage[last_idx].disable ||
             drv->states[last_idx].exit_latency > latency_req)) {
                 int i;
 
-                for (i = last_idx - 1; i > CPUIDLE_DRIVER_STATE_START; i--) {
+                for (i = last_idx - 1; i > first_idx; i--) {
                         if (drv->states[i].exit_latency <= latency_req)
                                 break;
                 }
@@ -110,7 +111,7 @@ static int ladder_select_state(struct cpuidle_driver *drv,
                 return i;
         }
 
-        if (last_idx > CPUIDLE_DRIVER_STATE_START &&
+        if (last_idx > first_idx &&
             last_residency < last_state->threshold.demotion_time) {
                 last_state->stats.demotion_count++;
                 last_state->stats.promotion_count = 0;
@@ -133,13 +134,14 @@ static int ladder_enable_device(struct cpuidle_driver *drv,
                                 struct cpuidle_device *dev)
 {
         int i;
+        int first_idx = drv->states[0].flags & CPUIDLE_FLAG_POLLING ? 1 : 0;
         struct ladder_device *ldev = &per_cpu(ladder_devices, dev->cpu);
         struct ladder_device_state *lstate;
         struct cpuidle_state *state;
 
-        ldev->last_state_idx = CPUIDLE_DRIVER_STATE_START;
+        ldev->last_state_idx = first_idx;
 
-        for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) {
+        for (i = first_idx; i < drv->state_count; i++) {
                 state = &drv->states[i];
                 lstate = &ldev->states[i];
 
@@ -151,7 +153,7 @@ static int ladder_enable_device(struct cpuidle_driver *drv,
 
                 if (i < drv->state_count - 1)
                         lstate->threshold.promotion_time = state->exit_latency;
-                if (i > CPUIDLE_DRIVER_STATE_START)
+                if (i > first_idx)
                         lstate->threshold.demotion_time = state->exit_latency;
         }
 
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 61b64c2b2cb8..48eaf2879228 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -324,8 +324,9 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
         expected_interval = get_typical_interval(data);
         expected_interval = min(expected_interval, data->next_timer_us);
 
-        if (CPUIDLE_DRIVER_STATE_START > 0) {
-                struct cpuidle_state *s = &drv->states[CPUIDLE_DRIVER_STATE_START];
+        first_idx = 0;
+        if (drv->states[0].flags & CPUIDLE_FLAG_POLLING) {
+                struct cpuidle_state *s = &drv->states[1];
                 unsigned int polling_threshold;
 
                 /*
@@ -336,12 +337,8 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
                 polling_threshold = max_t(unsigned int, 20, s->target_residency);
                 if (data->next_timer_us > polling_threshold &&
                     latency_req > s->exit_latency && !s->disabled &&
-                    !dev->states_usage[CPUIDLE_DRIVER_STATE_START].disable)
-                        first_idx = CPUIDLE_DRIVER_STATE_START;
-                else
-                        first_idx = CPUIDLE_DRIVER_STATE_START - 1;
-        } else {
-                first_idx = 0;
+                    !dev->states_usage[1].disable)
+                        first_idx = 1;
         }
 
         /*
diff --git a/drivers/cpuidle/poll_state.c b/drivers/cpuidle/poll_state.c
new file mode 100644
index 000000000000..7416b16287de
--- /dev/null
+++ b/drivers/cpuidle/poll_state.c
@@ -0,0 +1,37 @@
+/*
+ * poll_state.c - Polling idle state
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/cpuidle.h>
+#include <linux/sched.h>
+#include <linux/sched/idle.h>
+
+static int __cpuidle poll_idle(struct cpuidle_device *dev,
+                               struct cpuidle_driver *drv, int index)
+{
+        local_irq_enable();
+        if (!current_set_polling_and_test()) {
+                while (!need_resched())
+                        cpu_relax();
+        }
+        current_clr_polling();
+
+        return index;
+}
+
+void cpuidle_poll_state_init(struct cpuidle_driver *drv)
+{
+        struct cpuidle_state *state = &drv->states[0];
+
+        snprintf(state->name, CPUIDLE_NAME_LEN, "POLL");
+        snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE");
+        state->exit_latency = 0;
+        state->target_residency = 0;
+        state->power_usage = -1;
+        state->enter = poll_idle;
+        state->disabled = false;
+        state->flags = CPUIDLE_FLAG_POLLING;
+}
+EXPORT_SYMBOL_GPL(cpuidle_poll_state_init);
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index c2ae819a871c..7bf8739e33bc 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -1331,6 +1331,7 @@ static void __init intel_idle_cpuidle_driver_init(void)
 
         intel_idle_state_table_update();
 
+        cpuidle_poll_state_init(drv);
         drv->state_count = 1;
 
         for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index fc1e5d7fc1c7..5baacd3a0559 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -63,6 +63,7 @@ struct cpuidle_state {
 
 /* Idle State Flags */
 #define CPUIDLE_FLAG_NONE       (0x00)
+#define CPUIDLE_FLAG_POLLING    (0x01) /* polling state */
 #define CPUIDLE_FLAG_COUPLED    (0x02) /* state applies to multiple cpus */
 #define CPUIDLE_FLAG_TIMER_STOP (0x04)  /* timer is stopped on this state */
 
@@ -224,6 +225,12 @@ static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev,
 }
 #endif
 
+#ifdef CONFIG_ARCH_HAS_CPU_RELAX
+void cpuidle_poll_state_init(struct cpuidle_driver *drv);
+#else
+static inline void cpuidle_poll_state_init(struct cpuidle_driver *drv) {}
+#endif
+
 /******************************
  * CPUIDLE GOVERNOR INTERFACE *
  ******************************/
@@ -250,12 +257,6 @@ static inline int cpuidle_register_governor(struct cpuidle_governor *gov)
 {return 0;}
 #endif
 
-#ifdef CONFIG_ARCH_HAS_CPU_RELAX
-#define CPUIDLE_DRIVER_STATE_START      1
-#else
-#define CPUIDLE_DRIVER_STATE_START      0
-#endif
-
 #define CPU_PM_CPU_IDLE_ENTER(low_level_idle_enter, idx)        \
 ({                                                              \
         int __ret;                                              \