5 files changed, 40 insertions, 50 deletions

diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c
index fae958794339..146f97068022 100644
--- a/drivers/cpuidle/cpuidle-psci-domain.c
+++ b/drivers/cpuidle/cpuidle-psci-domain.c
@@ -67,12 +67,16 @@ static int psci_pd_init(struct device_node *np, bool use_osi)
 
 	/*
 	 * Allow power off when OSI has been successfully enabled.
-	 * PREEMPT_RT is not yet ready to enter domain idle states.
+	 * On a PREEMPT_RT based configuration the domain idle states are
+	 * supported, but only during system-wide suspend.
 	 */
-	if (use_osi && !IS_ENABLED(CONFIG_PREEMPT_RT))
+	if (use_osi) {
 		pd->power_off = psci_pd_power_off;
-	else
+		if (IS_ENABLED(CONFIG_PREEMPT_RT))
+			pd->flags |= GENPD_FLAG_RPM_ALWAYS_ON;
+	} else {
 		pd->flags |= GENPD_FLAG_ALWAYS_ON;
+	}
 
 	/* Use governor for CPU PM domains if it has some states to manage. */
 	pd_gov = pd->states ? &pm_domain_cpu_gov : NULL;
@@ -138,7 +142,6 @@ static const struct of_device_id psci_of_match[] = {
 static int psci_cpuidle_domain_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
-	struct device_node *node;
 	bool use_osi = psci_has_osi_support();
 	int ret = 0, pd_count = 0;
 
@@ -149,15 +152,13 @@ static int psci_cpuidle_domain_probe(struct platform_device *pdev)
 	 * Parse child nodes for the "#power-domain-cells" property and
 	 * initialize a genpd/genpd-of-provider pair when it's found.
 	 */
-	for_each_child_of_node(np, node) {
+	for_each_child_of_node_scoped(np, node) {
 		if (!of_property_present(node, "#power-domain-cells"))
 			continue;
 
 		ret = psci_pd_init(node, use_osi);
-		if (ret) {
-			of_node_put(node);
+		if (ret)
 			goto exit;
-		}
 
 		pd_count++;
 	}
diff --git a/drivers/cpuidle/cpuidle-psci.c b/drivers/cpuidle/cpuidle-psci.c
index 782030a27703..2562dc001fc1 100644
--- a/drivers/cpuidle/cpuidle-psci.c
+++ b/drivers/cpuidle/cpuidle-psci.c
@@ -37,6 +37,7 @@ struct psci_cpuidle_data {
 
 static DEFINE_PER_CPU_READ_MOSTLY(struct psci_cpuidle_data, psci_cpuidle_data);
 static DEFINE_PER_CPU(u32, domain_state);
+static bool psci_cpuidle_use_syscore;
 static bool psci_cpuidle_use_cpuhp;
 
 void psci_set_domain_state(u32 state)
@@ -166,6 +167,12 @@ static struct syscore_ops psci_idle_syscore_ops = {
 	.resume = psci_idle_syscore_resume,
 };
 
+static void psci_idle_init_syscore(void)
+{
+	if (psci_cpuidle_use_syscore)
+		register_syscore_ops(&psci_idle_syscore_ops);
+}
+
 static void psci_idle_init_cpuhp(void)
 {
 	int err;
@@ -173,8 +180,6 @@ static void psci_idle_init_cpuhp(void)
 	if (!psci_cpuidle_use_cpuhp)
 		return;
 
-	register_syscore_ops(&psci_idle_syscore_ops);
-
 	err = cpuhp_setup_state_nocalls(CPUHP_AP_CPU_PM_STARTING,
 					"cpuidle/psci:online",
 					psci_idle_cpuhp_up,
@@ -222,22 +227,23 @@ static int psci_dt_cpu_init_topology(struct cpuidle_driver *drv,
 	if (!psci_has_osi_support())
 		return 0;
 
-	if (IS_ENABLED(CONFIG_PREEMPT_RT))
-		return 0;
-
 	data->dev = dt_idle_attach_cpu(cpu, "psci");
 	if (IS_ERR_OR_NULL(data->dev))
 		return PTR_ERR_OR_ZERO(data->dev);
 
+	psci_cpuidle_use_syscore = true;
+
 	/*
 	 * Using the deepest state for the CPU to trigger a potential selection
 	 * of a shared state for the domain, assumes the domain states are all
-	 * deeper states.
+	 * deeper states. On PREEMPT_RT the hierarchical topology is limited to
+	 * s2ram and s2idle.
 	 */
-	drv->states[state_count - 1].flags |= CPUIDLE_FLAG_RCU_IDLE;
-	drv->states[state_count - 1].enter = psci_enter_domain_idle_state;
 	drv->states[state_count - 1].enter_s2idle = psci_enter_s2idle_domain_idle_state;
-	psci_cpuidle_use_cpuhp = true;
+	if (!IS_ENABLED(CONFIG_PREEMPT_RT)) {
+		drv->states[state_count - 1].enter = psci_enter_domain_idle_state;
+		psci_cpuidle_use_cpuhp = true;
+	}
 
 	return 0;
 }
@@ -313,6 +319,7 @@ static void psci_cpu_deinit_idle(int cpu)
 	struct psci_cpuidle_data *data = per_cpu_ptr(&psci_cpuidle_data, cpu);
 
 	dt_idle_detach_cpu(data->dev);
+	psci_cpuidle_use_syscore = false;
 	psci_cpuidle_use_cpuhp = false;
 }
 
@@ -409,6 +416,7 @@ static int psci_cpuidle_probe(struct platform_device *pdev)
 			goto out_fail;
 	}
 
+	psci_idle_init_syscore();
 	psci_idle_init_cpuhp();
 	return 0;
 
diff --git a/drivers/cpuidle/cpuidle-riscv-sbi.c b/drivers/cpuidle/cpuidle-riscv-sbi.c
index a6e123dfe394..d228b4d18d56 100644
--- a/drivers/cpuidle/cpuidle-riscv-sbi.c
+++ b/drivers/cpuidle/cpuidle-riscv-sbi.c
@@ -8,6 +8,7 @@
 
 #define pr_fmt(fmt) "cpuidle-riscv-sbi: " fmt
 
+#include <linux/cleanup.h>
 #include <linux/cpuhotplug.h>
 #include <linux/cpuidle.h>
 #include <linux/cpumask.h>
@@ -236,19 +237,16 @@ static int sbi_cpuidle_dt_init_states(struct device *dev,
 {
 	struct sbi_cpuidle_data *data = per_cpu_ptr(&sbi_cpuidle_data, cpu);
 	struct device_node *state_node;
-	struct device_node *cpu_node;
 	u32 *states;
 	int i, ret;
 
-	cpu_node = of_cpu_device_node_get(cpu);
+	struct device_node *cpu_node __free(device_node) = of_cpu_device_node_get(cpu);
 	if (!cpu_node)
 		return -ENODEV;
 
 	states = devm_kcalloc(dev, state_count, sizeof(*states), GFP_KERNEL);
-	if (!states) {
-		ret = -ENOMEM;
-		goto fail;
-	}
+	if (!states)
+		return -ENOMEM;
 
 	/* Parse SBI specific details from state DT nodes */
 	for (i = 1; i < state_count; i++) {
@@ -264,10 +262,8 @@ static int sbi_cpuidle_dt_init_states(struct device *dev,
 
 		pr_debug("sbi-state %#x index %d\n", states[i], i);
 	}
-	if (i != state_count) {
-		ret = -ENODEV;
-		goto fail;
-	}
+	if (i != state_count)
+		return -ENODEV;
 
 	/* Initialize optional data, used for the hierarchical topology. */
 	ret = sbi_dt_cpu_init_topology(drv, data, state_count, cpu);
@@ -277,10 +273,7 @@ static int sbi_cpuidle_dt_init_states(struct device *dev,
 	/* Store states in the per-cpu struct. */
 	data->states = states;
 
-fail:
-	of_node_put(cpu_node);
-
-	return ret;
+	return 0;
 }
 
 static void sbi_cpuidle_deinit_cpu(int cpu)
@@ -455,7 +448,6 @@ static void sbi_pd_remove(void)
 
 static int sbi_genpd_probe(struct device_node *np)
 {
-	struct device_node *node;
 	int ret = 0, pd_count = 0;
 
 	if (!np)
@@ -465,13 +457,13 @@ static int sbi_genpd_probe(struct device_node *np)
 	 * Parse child nodes for the "#power-domain-cells" property and
 	 * initialize a genpd/genpd-of-provider pair when it's found.
 	 */
-	for_each_child_of_node(np, node) {
+	for_each_child_of_node_scoped(np, node) {
 		if (!of_property_present(node, "#power-domain-cells"))
 			continue;
 
 		ret = sbi_pd_init(node);
 		if (ret)
-			goto put_node;
+			goto remove_pd;
 
 		pd_count++;
 	}
@@ -487,8 +479,6 @@ static int sbi_genpd_probe(struct device_node *np)
 
 	return 0;
 
-put_node:
-	of_node_put(node);
 remove_pd:
 	sbi_pd_remove();
 	pr_err("failed to create CPU PM domains ret=%d\n", ret);
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 02e40fd7d948..9e418aec1755 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -228,10 +228,7 @@ noinstr int cpuidle_enter_state(struct cpuidle_device *dev,
 	if (broadcast && tick_broadcast_enter()) {
 		index = find_deepest_state(drv, dev, target_state->exit_latency_ns,
 					   CPUIDLE_FLAG_TIMER_STOP, false);
-		if (index < 0) {
-			default_idle_call();
-			return -EBUSY;
-		}
+
 		target_state = &drv->states[index];
 		broadcast = false;
 	}
diff --git a/drivers/cpuidle/dt_idle_genpd.c b/drivers/cpuidle/dt_idle_genpd.c
index 1af63c189039..203e9b754aea 100644
--- a/drivers/cpuidle/dt_idle_genpd.c
+++ b/drivers/cpuidle/dt_idle_genpd.c
@@ -130,11 +130,10 @@ out:
 
 int dt_idle_pd_init_topology(struct device_node *np)
 {
-	struct device_node *node;
 	struct of_phandle_args child, parent;
 	int ret;
 
-	for_each_child_of_node(np, node) {
+	for_each_child_of_node_scoped(np, node) {
 		if (of_parse_phandle_with_args(node, "power-domains",
 					"#power-domain-cells", 0, &parent))
 			continue;
@@ -143,10 +142,8 @@ int dt_idle_pd_init_topology(struct device_node *np)
 		child.args_count = 0;
 		ret = of_genpd_add_subdomain(&parent, &child);
 		of_node_put(parent.np);
-		if (ret) {
-			of_node_put(node);
+		if (ret)
 			return ret;
-		}
 	}
 
 	return 0;
@@ -154,11 +151,10 @@ int dt_idle_pd_init_topology(struct device_node *np)
 
 int dt_idle_pd_remove_topology(struct device_node *np)
 {
-	struct device_node *node;
 	struct of_phandle_args child, parent;
 	int ret;
 
-	for_each_child_of_node(np, node) {
+	for_each_child_of_node_scoped(np, node) {
 		if (of_parse_phandle_with_args(node, "power-domains",
 					"#power-domain-cells", 0, &parent))
 			continue;
@@ -167,10 +163,8 @@ int dt_idle_pd_remove_topology(struct device_node *np)
 		child.args_count = 0;
 		ret = of_genpd_remove_subdomain(&parent, &child);
 		of_node_put(parent.np);
-		if (ret) {
-			of_node_put(node);
+		if (ret)
 			return ret;
-		}
 	}
 
 	return 0;