181d549e0SLorenzo Pieralisi // SPDX-License-Identifier: GPL-2.0-only
281d549e0SLorenzo Pieralisi /*
381d549e0SLorenzo Pieralisi * PSCI CPU idle driver.
481d549e0SLorenzo Pieralisi *
581d549e0SLorenzo Pieralisi * Copyright (C) 2019 ARM Ltd.
681d549e0SLorenzo Pieralisi * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
781d549e0SLorenzo Pieralisi */
881d549e0SLorenzo Pieralisi
981d549e0SLorenzo Pieralisi #define pr_fmt(fmt) "CPUidle PSCI: " fmt
1081d549e0SLorenzo Pieralisi
119c6ceecbSUlf Hansson #include <linux/cpuhotplug.h>
12fc7a3d9eSDaniel Lezcano #include <linux/cpu_cooling.h>
1381d549e0SLorenzo Pieralisi #include <linux/cpuidle.h>
1481d549e0SLorenzo Pieralisi #include <linux/cpumask.h>
1581d549e0SLorenzo Pieralisi #include <linux/cpu_pm.h>
1681d549e0SLorenzo Pieralisi #include <linux/kernel.h>
1781d549e0SLorenzo Pieralisi #include <linux/module.h>
1881d549e0SLorenzo Pieralisi #include <linux/of.h>
19166bf835SUlf Hansson #include <linux/platform_device.h>
2081d549e0SLorenzo Pieralisi #include <linux/psci.h>
21670c90deSUlf Hansson #include <linux/pm_domain.h>
22ce85aef5SUlf Hansson #include <linux/pm_runtime.h>
2381d549e0SLorenzo Pieralisi #include <linux/slab.h>
24166bf835SUlf Hansson #include <linux/string.h>
25171b66e2SUlf Hansson #include <linux/syscore_ops.h>
2681d549e0SLorenzo Pieralisi
2781d549e0SLorenzo Pieralisi #include <asm/cpuidle.h>
2881d549e0SLorenzo Pieralisi
298554951aSUlf Hansson #include "cpuidle-psci.h"
3081d549e0SLorenzo Pieralisi #include "dt_idle_states.h"
3181d549e0SLorenzo Pieralisi
328554951aSUlf Hansson struct psci_cpuidle_data {
338554951aSUlf Hansson u32 *psci_states;
348554951aSUlf Hansson struct device *dev;
358554951aSUlf Hansson };
368554951aSUlf Hansson
378554951aSUlf Hansson static DEFINE_PER_CPU_READ_MOSTLY(struct psci_cpuidle_data, psci_cpuidle_data);
38a0cf3194SUlf Hansson static DEFINE_PER_CPU(u32, domain_state);
39166bf835SUlf Hansson static bool psci_cpuidle_use_cpuhp;
40a0cf3194SUlf Hansson
psci_set_domain_state(u32 state)41a65a397fSUlf Hansson void psci_set_domain_state(u32 state)
42a0cf3194SUlf Hansson {
43a0cf3194SUlf Hansson __this_cpu_write(domain_state, state);
44a0cf3194SUlf Hansson }
45a0cf3194SUlf Hansson
psci_get_domain_state(void)46a0cf3194SUlf Hansson static inline u32 psci_get_domain_state(void)
47a0cf3194SUlf Hansson {
48a0cf3194SUlf Hansson return __this_cpu_read(domain_state);
49a0cf3194SUlf Hansson }
50a0cf3194SUlf Hansson
__psci_enter_domain_idle_state(struct cpuidle_device * dev,struct cpuidle_driver * drv,int idx,bool s2idle)5169e26b4fSPeter Zijlstra static __cpuidle int __psci_enter_domain_idle_state(struct cpuidle_device *dev,
52670c90deSUlf Hansson struct cpuidle_driver *drv, int idx,
53670c90deSUlf Hansson bool s2idle)
54a0cf3194SUlf Hansson {
55a0cf3194SUlf Hansson struct psci_cpuidle_data *data = this_cpu_ptr(&psci_cpuidle_data);
56a0cf3194SUlf Hansson u32 *states = data->psci_states;
57ce85aef5SUlf Hansson struct device *pd_dev = data->dev;
58ce85aef5SUlf Hansson u32 state;
59a0cf3194SUlf Hansson int ret;
60a0cf3194SUlf Hansson
618b7ce5e4SUlf Hansson ret = cpu_pm_enter();
628b7ce5e4SUlf Hansson if (ret)
638b7ce5e4SUlf Hansson return -1;
648b7ce5e4SUlf Hansson
65ce85aef5SUlf Hansson /* Do runtime PM to manage a hierarchical CPU toplogy. */
66670c90deSUlf Hansson if (s2idle)
67670c90deSUlf Hansson dev_pm_genpd_suspend(pd_dev);
68670c90deSUlf Hansson else
69670c90deSUlf Hansson pm_runtime_put_sync_suspend(pd_dev);
70e038f7b8SPeter Zijlstra
71ce85aef5SUlf Hansson state = psci_get_domain_state();
72a0cf3194SUlf Hansson if (!state)
73a0cf3194SUlf Hansson state = states[idx];
74a0cf3194SUlf Hansson
758b7ce5e4SUlf Hansson ret = psci_cpu_suspend_enter(state) ? -1 : idx;
76a0cf3194SUlf Hansson
77670c90deSUlf Hansson if (s2idle)
78670c90deSUlf Hansson dev_pm_genpd_resume(pd_dev);
79670c90deSUlf Hansson else
80670c90deSUlf Hansson pm_runtime_get_sync(pd_dev);
81ce85aef5SUlf Hansson
828b7ce5e4SUlf Hansson cpu_pm_exit();
838b7ce5e4SUlf Hansson
84a0cf3194SUlf Hansson /* Clear the domain state to start fresh when back from idle. */
85a0cf3194SUlf Hansson psci_set_domain_state(0);
86a0cf3194SUlf Hansson return ret;
87a0cf3194SUlf Hansson }
889ffeb6d0SLorenzo Pieralisi
psci_enter_domain_idle_state(struct cpuidle_device * dev,struct cpuidle_driver * drv,int idx)89670c90deSUlf Hansson static int psci_enter_domain_idle_state(struct cpuidle_device *dev,
90670c90deSUlf Hansson struct cpuidle_driver *drv, int idx)
91670c90deSUlf Hansson {
92670c90deSUlf Hansson return __psci_enter_domain_idle_state(dev, drv, idx, false);
93670c90deSUlf Hansson }
94670c90deSUlf Hansson
psci_enter_s2idle_domain_idle_state(struct cpuidle_device * dev,struct cpuidle_driver * drv,int idx)95670c90deSUlf Hansson static int psci_enter_s2idle_domain_idle_state(struct cpuidle_device *dev,
96670c90deSUlf Hansson struct cpuidle_driver *drv,
97670c90deSUlf Hansson int idx)
98670c90deSUlf Hansson {
99670c90deSUlf Hansson return __psci_enter_domain_idle_state(dev, drv, idx, true);
100670c90deSUlf Hansson }
101670c90deSUlf Hansson
psci_idle_cpuhp_up(unsigned int cpu)1029c6ceecbSUlf Hansson static int psci_idle_cpuhp_up(unsigned int cpu)
1039c6ceecbSUlf Hansson {
1049c6ceecbSUlf Hansson struct device *pd_dev = __this_cpu_read(psci_cpuidle_data.dev);
1059c6ceecbSUlf Hansson
1069c6ceecbSUlf Hansson if (pd_dev)
1079c6ceecbSUlf Hansson pm_runtime_get_sync(pd_dev);
1089c6ceecbSUlf Hansson
1099c6ceecbSUlf Hansson return 0;
1109c6ceecbSUlf Hansson }
1119c6ceecbSUlf Hansson
psci_idle_cpuhp_down(unsigned int cpu)1129c6ceecbSUlf Hansson static int psci_idle_cpuhp_down(unsigned int cpu)
1139c6ceecbSUlf Hansson {
1149c6ceecbSUlf Hansson struct device *pd_dev = __this_cpu_read(psci_cpuidle_data.dev);
1159c6ceecbSUlf Hansson
1169c6ceecbSUlf Hansson if (pd_dev) {
1179c6ceecbSUlf Hansson pm_runtime_put_sync(pd_dev);
1189c6ceecbSUlf Hansson /* Clear domain state to start fresh at next online. */
1199c6ceecbSUlf Hansson psci_set_domain_state(0);
1209c6ceecbSUlf Hansson }
1219c6ceecbSUlf Hansson
1229c6ceecbSUlf Hansson return 0;
1239c6ceecbSUlf Hansson }
1249c6ceecbSUlf Hansson
psci_idle_syscore_switch(bool suspend)125171b66e2SUlf Hansson static void psci_idle_syscore_switch(bool suspend)
126171b66e2SUlf Hansson {
127171b66e2SUlf Hansson bool cleared = false;
128171b66e2SUlf Hansson struct device *dev;
129171b66e2SUlf Hansson int cpu;
130171b66e2SUlf Hansson
131171b66e2SUlf Hansson for_each_possible_cpu(cpu) {
132171b66e2SUlf Hansson dev = per_cpu_ptr(&psci_cpuidle_data, cpu)->dev;
133171b66e2SUlf Hansson
134171b66e2SUlf Hansson if (dev && suspend) {
135171b66e2SUlf Hansson dev_pm_genpd_suspend(dev);
136171b66e2SUlf Hansson } else if (dev) {
137171b66e2SUlf Hansson dev_pm_genpd_resume(dev);
138171b66e2SUlf Hansson
139171b66e2SUlf Hansson /* Account for userspace having offlined a CPU. */
140171b66e2SUlf Hansson if (pm_runtime_status_suspended(dev))
141171b66e2SUlf Hansson pm_runtime_set_active(dev);
142171b66e2SUlf Hansson
143171b66e2SUlf Hansson /* Clear domain state to re-start fresh. */
144171b66e2SUlf Hansson if (!cleared) {
145171b66e2SUlf Hansson psci_set_domain_state(0);
146171b66e2SUlf Hansson cleared = true;
147171b66e2SUlf Hansson }
148171b66e2SUlf Hansson }
149171b66e2SUlf Hansson }
150171b66e2SUlf Hansson }
151171b66e2SUlf Hansson
psci_idle_syscore_suspend(void)152171b66e2SUlf Hansson static int psci_idle_syscore_suspend(void)
153171b66e2SUlf Hansson {
154171b66e2SUlf Hansson psci_idle_syscore_switch(true);
155171b66e2SUlf Hansson return 0;
156171b66e2SUlf Hansson }
157171b66e2SUlf Hansson
psci_idle_syscore_resume(void)158171b66e2SUlf Hansson static void psci_idle_syscore_resume(void)
159171b66e2SUlf Hansson {
160171b66e2SUlf Hansson psci_idle_syscore_switch(false);
161171b66e2SUlf Hansson }
162171b66e2SUlf Hansson
163171b66e2SUlf Hansson static struct syscore_ops psci_idle_syscore_ops = {
164171b66e2SUlf Hansson .suspend = psci_idle_syscore_suspend,
165171b66e2SUlf Hansson .resume = psci_idle_syscore_resume,
166171b66e2SUlf Hansson };
167171b66e2SUlf Hansson
psci_idle_init_cpuhp(void)168166bf835SUlf Hansson static void psci_idle_init_cpuhp(void)
1699c6ceecbSUlf Hansson {
1709c6ceecbSUlf Hansson int err;
1719c6ceecbSUlf Hansson
1729c6ceecbSUlf Hansson if (!psci_cpuidle_use_cpuhp)
1739c6ceecbSUlf Hansson return;
1749c6ceecbSUlf Hansson
175171b66e2SUlf Hansson register_syscore_ops(&psci_idle_syscore_ops);
176171b66e2SUlf Hansson
1779c6ceecbSUlf Hansson err = cpuhp_setup_state_nocalls(CPUHP_AP_CPU_PM_STARTING,
1789c6ceecbSUlf Hansson "cpuidle/psci:online",
1799c6ceecbSUlf Hansson psci_idle_cpuhp_up,
1809c6ceecbSUlf Hansson psci_idle_cpuhp_down);
1819c6ceecbSUlf Hansson if (err)
1829c6ceecbSUlf Hansson pr_warn("Failed %d while setup cpuhp state\n", err);
1839c6ceecbSUlf Hansson }
1849c6ceecbSUlf Hansson
psci_enter_idle_state(struct cpuidle_device * dev,struct cpuidle_driver * drv,int idx)18569e26b4fSPeter Zijlstra static __cpuidle int psci_enter_idle_state(struct cpuidle_device *dev,
18681d549e0SLorenzo Pieralisi struct cpuidle_driver *drv, int idx)
18781d549e0SLorenzo Pieralisi {
1888554951aSUlf Hansson u32 *state = __this_cpu_read(psci_cpuidle_data.psci_states);
1899ffeb6d0SLorenzo Pieralisi
19019235e47SPeter Zijlstra return CPU_PM_CPU_IDLE_ENTER_PARAM_RCU(psci_cpu_suspend_enter, idx, state[idx]);
19181d549e0SLorenzo Pieralisi }
19281d549e0SLorenzo Pieralisi
193166bf835SUlf Hansson static const struct of_device_id psci_idle_state_match[] = {
19481d549e0SLorenzo Pieralisi { .compatible = "arm,idle-state",
19581d549e0SLorenzo Pieralisi .data = psci_enter_idle_state },
19681d549e0SLorenzo Pieralisi { },
19781d549e0SLorenzo Pieralisi };
19881d549e0SLorenzo Pieralisi
psci_dt_parse_state_node(struct device_node * np,u32 * state)199166bf835SUlf Hansson int psci_dt_parse_state_node(struct device_node *np, u32 *state)
2009ffeb6d0SLorenzo Pieralisi {
2019ffeb6d0SLorenzo Pieralisi int err = of_property_read_u32(np, "arm,psci-suspend-param", state);
2029ffeb6d0SLorenzo Pieralisi
2039ffeb6d0SLorenzo Pieralisi if (err) {
2049ffeb6d0SLorenzo Pieralisi pr_warn("%pOF missing arm,psci-suspend-param property\n", np);
2059ffeb6d0SLorenzo Pieralisi return err;
2069ffeb6d0SLorenzo Pieralisi }
2079ffeb6d0SLorenzo Pieralisi
2089ffeb6d0SLorenzo Pieralisi if (!psci_power_state_is_valid(*state)) {
2099ffeb6d0SLorenzo Pieralisi pr_warn("Invalid PSCI power state %#x\n", *state);
2109ffeb6d0SLorenzo Pieralisi return -EINVAL;
2119ffeb6d0SLorenzo Pieralisi }
2129ffeb6d0SLorenzo Pieralisi
2139ffeb6d0SLorenzo Pieralisi return 0;
2149ffeb6d0SLorenzo Pieralisi }
2159ffeb6d0SLorenzo Pieralisi
psci_dt_cpu_init_topology(struct cpuidle_driver * drv,struct psci_cpuidle_data * data,unsigned int state_count,int cpu)216166bf835SUlf Hansson static int psci_dt_cpu_init_topology(struct cpuidle_driver *drv,
2177fbee48eSUlf Hansson struct psci_cpuidle_data *data,
2187fbee48eSUlf Hansson unsigned int state_count, int cpu)
2197fbee48eSUlf Hansson {
2207fbee48eSUlf Hansson /* Currently limit the hierarchical topology to be used in OSI mode. */
2217fbee48eSUlf Hansson if (!psci_has_osi_support())
2227fbee48eSUlf Hansson return 0;
2237fbee48eSUlf Hansson
224*f9901f64SKrzysztof Kozlowski if (IS_ENABLED(CONFIG_PREEMPT_RT))
225*f9901f64SKrzysztof Kozlowski return 0;
226*f9901f64SKrzysztof Kozlowski
2277fbee48eSUlf Hansson data->dev = psci_dt_attach_cpu(cpu);
2287fbee48eSUlf Hansson if (IS_ERR_OR_NULL(data->dev))
2297fbee48eSUlf Hansson return PTR_ERR_OR_ZERO(data->dev);
2307fbee48eSUlf Hansson
2317fbee48eSUlf Hansson /*
2327fbee48eSUlf Hansson * Using the deepest state for the CPU to trigger a potential selection
2337fbee48eSUlf Hansson * of a shared state for the domain, assumes the domain states are all
2347fbee48eSUlf Hansson * deeper states.
2357fbee48eSUlf Hansson */
236e038f7b8SPeter Zijlstra drv->states[state_count - 1].flags |= CPUIDLE_FLAG_RCU_IDLE;
2377fbee48eSUlf Hansson drv->states[state_count - 1].enter = psci_enter_domain_idle_state;
238670c90deSUlf Hansson drv->states[state_count - 1].enter_s2idle = psci_enter_s2idle_domain_idle_state;
2397fbee48eSUlf Hansson psci_cpuidle_use_cpuhp = true;
2407fbee48eSUlf Hansson
2417fbee48eSUlf Hansson return 0;
2427fbee48eSUlf Hansson }
2437fbee48eSUlf Hansson
psci_dt_cpu_init_idle(struct device * dev,struct cpuidle_driver * drv,struct device_node * cpu_node,unsigned int state_count,int cpu)244166bf835SUlf Hansson static int psci_dt_cpu_init_idle(struct device *dev, struct cpuidle_driver *drv,
245a0cf3194SUlf Hansson struct device_node *cpu_node,
2461595e4b0SUlf Hansson unsigned int state_count, int cpu)
2479ffeb6d0SLorenzo Pieralisi {
2481595e4b0SUlf Hansson int i, ret = 0;
2499ffeb6d0SLorenzo Pieralisi u32 *psci_states;
2509ffeb6d0SLorenzo Pieralisi struct device_node *state_node;
2518554951aSUlf Hansson struct psci_cpuidle_data *data = per_cpu_ptr(&psci_cpuidle_data, cpu);
2529ffeb6d0SLorenzo Pieralisi
2531595e4b0SUlf Hansson state_count++; /* Add WFI state too */
254166bf835SUlf Hansson psci_states = devm_kcalloc(dev, state_count, sizeof(*psci_states),
255166bf835SUlf Hansson GFP_KERNEL);
2569ffeb6d0SLorenzo Pieralisi if (!psci_states)
2579ffeb6d0SLorenzo Pieralisi return -ENOMEM;
2589ffeb6d0SLorenzo Pieralisi
2591595e4b0SUlf Hansson for (i = 1; i < state_count; i++) {
260f08cfbfaSUlf Hansson state_node = of_get_cpu_state_node(cpu_node, i - 1);
2611595e4b0SUlf Hansson if (!state_node)
2621595e4b0SUlf Hansson break;
2631595e4b0SUlf Hansson
2649ffeb6d0SLorenzo Pieralisi ret = psci_dt_parse_state_node(state_node, &psci_states[i]);
2659ffeb6d0SLorenzo Pieralisi of_node_put(state_node);
2669ffeb6d0SLorenzo Pieralisi
2679ffeb6d0SLorenzo Pieralisi if (ret)
268166bf835SUlf Hansson return ret;
2699ffeb6d0SLorenzo Pieralisi
2709ffeb6d0SLorenzo Pieralisi pr_debug("psci-power-state %#x index %d\n", psci_states[i], i);
2719ffeb6d0SLorenzo Pieralisi }
2729ffeb6d0SLorenzo Pieralisi
273166bf835SUlf Hansson if (i != state_count)
274166bf835SUlf Hansson return -ENODEV;
2751595e4b0SUlf Hansson
2767fbee48eSUlf Hansson /* Initialize optional data, used for the hierarchical topology. */
2777fbee48eSUlf Hansson ret = psci_dt_cpu_init_topology(drv, data, state_count, cpu);
2787fbee48eSUlf Hansson if (ret < 0)
279166bf835SUlf Hansson return ret;
2808554951aSUlf Hansson
2818554951aSUlf Hansson /* Idle states parsed correctly, store them in the per-cpu struct. */
2828554951aSUlf Hansson data->psci_states = psci_states;
2839ffeb6d0SLorenzo Pieralisi return 0;
2849ffeb6d0SLorenzo Pieralisi }
2859ffeb6d0SLorenzo Pieralisi
psci_cpu_init_idle(struct device * dev,struct cpuidle_driver * drv,unsigned int cpu,unsigned int state_count)286166bf835SUlf Hansson static int psci_cpu_init_idle(struct device *dev, struct cpuidle_driver *drv,
287a0cf3194SUlf Hansson unsigned int cpu, unsigned int state_count)
2889ffeb6d0SLorenzo Pieralisi {
2899ffeb6d0SLorenzo Pieralisi struct device_node *cpu_node;
2909ffeb6d0SLorenzo Pieralisi int ret;
2919ffeb6d0SLorenzo Pieralisi
2929ffeb6d0SLorenzo Pieralisi /*
2939ffeb6d0SLorenzo Pieralisi * If the PSCI cpu_suspend function hook has not been initialized
2949ffeb6d0SLorenzo Pieralisi * idle states must not be enabled, so bail out
2959ffeb6d0SLorenzo Pieralisi */
2969ffeb6d0SLorenzo Pieralisi if (!psci_ops.cpu_suspend)
2979ffeb6d0SLorenzo Pieralisi return -EOPNOTSUPP;
2989ffeb6d0SLorenzo Pieralisi
2999ffeb6d0SLorenzo Pieralisi cpu_node = of_cpu_device_node_get(cpu);
3009ffeb6d0SLorenzo Pieralisi if (!cpu_node)
3019ffeb6d0SLorenzo Pieralisi return -ENODEV;
3029ffeb6d0SLorenzo Pieralisi
303166bf835SUlf Hansson ret = psci_dt_cpu_init_idle(dev, drv, cpu_node, state_count, cpu);
3049ffeb6d0SLorenzo Pieralisi
3059ffeb6d0SLorenzo Pieralisi of_node_put(cpu_node);
3069ffeb6d0SLorenzo Pieralisi
3079ffeb6d0SLorenzo Pieralisi return ret;
3089ffeb6d0SLorenzo Pieralisi }
3099ffeb6d0SLorenzo Pieralisi
psci_cpu_deinit_idle(int cpu)310166bf835SUlf Hansson static void psci_cpu_deinit_idle(int cpu)
311166bf835SUlf Hansson {
312166bf835SUlf Hansson struct psci_cpuidle_data *data = per_cpu_ptr(&psci_cpuidle_data, cpu);
313166bf835SUlf Hansson
314166bf835SUlf Hansson psci_dt_detach_cpu(data->dev);
315166bf835SUlf Hansson psci_cpuidle_use_cpuhp = false;
316166bf835SUlf Hansson }
317166bf835SUlf Hansson
psci_idle_init_cpu(struct device * dev,int cpu)318166bf835SUlf Hansson static int psci_idle_init_cpu(struct device *dev, int cpu)
31981d549e0SLorenzo Pieralisi {
32081d549e0SLorenzo Pieralisi struct cpuidle_driver *drv;
32181d549e0SLorenzo Pieralisi struct device_node *cpu_node;
32281d549e0SLorenzo Pieralisi const char *enable_method;
32381d549e0SLorenzo Pieralisi int ret = 0;
32481d549e0SLorenzo Pieralisi
32581d549e0SLorenzo Pieralisi cpu_node = of_cpu_device_node_get(cpu);
32681d549e0SLorenzo Pieralisi if (!cpu_node)
32781d549e0SLorenzo Pieralisi return -ENODEV;
32881d549e0SLorenzo Pieralisi
32981d549e0SLorenzo Pieralisi /*
33081d549e0SLorenzo Pieralisi * Check whether the enable-method for the cpu is PSCI, fail
33181d549e0SLorenzo Pieralisi * if it is not.
33281d549e0SLorenzo Pieralisi */
33381d549e0SLorenzo Pieralisi enable_method = of_get_property(cpu_node, "enable-method", NULL);
33481d549e0SLorenzo Pieralisi if (!enable_method || (strcmp(enable_method, "psci")))
33581d549e0SLorenzo Pieralisi ret = -ENODEV;
33681d549e0SLorenzo Pieralisi
33781d549e0SLorenzo Pieralisi of_node_put(cpu_node);
33881d549e0SLorenzo Pieralisi if (ret)
33981d549e0SLorenzo Pieralisi return ret;
34081d549e0SLorenzo Pieralisi
341166bf835SUlf Hansson drv = devm_kzalloc(dev, sizeof(*drv), GFP_KERNEL);
34281d549e0SLorenzo Pieralisi if (!drv)
34381d549e0SLorenzo Pieralisi return -ENOMEM;
34481d549e0SLorenzo Pieralisi
345166bf835SUlf Hansson drv->name = "psci_idle";
346166bf835SUlf Hansson drv->owner = THIS_MODULE;
34781d549e0SLorenzo Pieralisi drv->cpumask = (struct cpumask *)cpumask_of(cpu);
34881d549e0SLorenzo Pieralisi
34981d549e0SLorenzo Pieralisi /*
350166bf835SUlf Hansson * PSCI idle states relies on architectural WFI to be represented as
351166bf835SUlf Hansson * state index 0.
352166bf835SUlf Hansson */
353166bf835SUlf Hansson drv->states[0].enter = psci_enter_idle_state;
354166bf835SUlf Hansson drv->states[0].exit_latency = 1;
355166bf835SUlf Hansson drv->states[0].target_residency = 1;
356166bf835SUlf Hansson drv->states[0].power_usage = UINT_MAX;
357166bf835SUlf Hansson strcpy(drv->states[0].name, "WFI");
358166bf835SUlf Hansson strcpy(drv->states[0].desc, "ARM WFI");
359166bf835SUlf Hansson
360166bf835SUlf Hansson /*
36181d549e0SLorenzo Pieralisi * If no DT idle states are detected (ret == 0) let the driver
36281d549e0SLorenzo Pieralisi * initialization fail accordingly since there is no reason to
36381d549e0SLorenzo Pieralisi * initialize the idle driver if only wfi is supported, the
36481d549e0SLorenzo Pieralisi * default archictectural back-end already executes wfi
36581d549e0SLorenzo Pieralisi * on idle entry.
36681d549e0SLorenzo Pieralisi */
36781d549e0SLorenzo Pieralisi ret = dt_init_idle_driver(drv, psci_idle_state_match, 1);
368166bf835SUlf Hansson if (ret <= 0)
369166bf835SUlf Hansson return ret ? : -ENODEV;
37081d549e0SLorenzo Pieralisi
37181d549e0SLorenzo Pieralisi /*
37281d549e0SLorenzo Pieralisi * Initialize PSCI idle states.
37381d549e0SLorenzo Pieralisi */
374166bf835SUlf Hansson ret = psci_cpu_init_idle(dev, drv, cpu, ret);
37581d549e0SLorenzo Pieralisi if (ret) {
37681d549e0SLorenzo Pieralisi pr_err("CPU %d failed to PSCI idle\n", cpu);
377166bf835SUlf Hansson return ret;
37881d549e0SLorenzo Pieralisi }
37981d549e0SLorenzo Pieralisi
38081d549e0SLorenzo Pieralisi ret = cpuidle_register(drv, NULL);
38181d549e0SLorenzo Pieralisi if (ret)
382166bf835SUlf Hansson goto deinit;
38381d549e0SLorenzo Pieralisi
384fc7a3d9eSDaniel Lezcano cpuidle_cooling_register(drv);
385fc7a3d9eSDaniel Lezcano
38681d549e0SLorenzo Pieralisi return 0;
387166bf835SUlf Hansson deinit:
388166bf835SUlf Hansson psci_cpu_deinit_idle(cpu);
38981d549e0SLorenzo Pieralisi return ret;
39081d549e0SLorenzo Pieralisi }
39181d549e0SLorenzo Pieralisi
39281d549e0SLorenzo Pieralisi /*
393166bf835SUlf Hansson * psci_idle_probe - Initializes PSCI cpuidle driver
39481d549e0SLorenzo Pieralisi *
39581d549e0SLorenzo Pieralisi * Initializes PSCI cpuidle driver for all CPUs, if any CPU fails
39681d549e0SLorenzo Pieralisi * to register cpuidle driver then rollback to cancel all CPUs
39781d549e0SLorenzo Pieralisi * registration.
39881d549e0SLorenzo Pieralisi */
psci_cpuidle_probe(struct platform_device * pdev)399166bf835SUlf Hansson static int psci_cpuidle_probe(struct platform_device *pdev)
40081d549e0SLorenzo Pieralisi {
40181d549e0SLorenzo Pieralisi int cpu, ret;
40281d549e0SLorenzo Pieralisi struct cpuidle_driver *drv;
40381d549e0SLorenzo Pieralisi struct cpuidle_device *dev;
40481d549e0SLorenzo Pieralisi
40581d549e0SLorenzo Pieralisi for_each_possible_cpu(cpu) {
406166bf835SUlf Hansson ret = psci_idle_init_cpu(&pdev->dev, cpu);
40781d549e0SLorenzo Pieralisi if (ret)
40881d549e0SLorenzo Pieralisi goto out_fail;
40981d549e0SLorenzo Pieralisi }
41081d549e0SLorenzo Pieralisi
4119c6ceecbSUlf Hansson psci_idle_init_cpuhp();
41281d549e0SLorenzo Pieralisi return 0;
41381d549e0SLorenzo Pieralisi
41481d549e0SLorenzo Pieralisi out_fail:
41581d549e0SLorenzo Pieralisi while (--cpu >= 0) {
41681d549e0SLorenzo Pieralisi dev = per_cpu(cpuidle_devices, cpu);
41781d549e0SLorenzo Pieralisi drv = cpuidle_get_cpu_driver(dev);
41881d549e0SLorenzo Pieralisi cpuidle_unregister(drv);
419166bf835SUlf Hansson psci_cpu_deinit_idle(cpu);
42081d549e0SLorenzo Pieralisi }
42181d549e0SLorenzo Pieralisi
42281d549e0SLorenzo Pieralisi return ret;
42381d549e0SLorenzo Pieralisi }
424166bf835SUlf Hansson
425166bf835SUlf Hansson static struct platform_driver psci_cpuidle_driver = {
426166bf835SUlf Hansson .probe = psci_cpuidle_probe,
427166bf835SUlf Hansson .driver = {
428166bf835SUlf Hansson .name = "psci-cpuidle",
429166bf835SUlf Hansson },
430166bf835SUlf Hansson };
431166bf835SUlf Hansson
psci_idle_init(void)432166bf835SUlf Hansson static int __init psci_idle_init(void)
433166bf835SUlf Hansson {
434166bf835SUlf Hansson struct platform_device *pdev;
435166bf835SUlf Hansson int ret;
436166bf835SUlf Hansson
437166bf835SUlf Hansson ret = platform_driver_register(&psci_cpuidle_driver);
438166bf835SUlf Hansson if (ret)
439166bf835SUlf Hansson return ret;
440166bf835SUlf Hansson
441166bf835SUlf Hansson pdev = platform_device_register_simple("psci-cpuidle", -1, NULL, 0);
442166bf835SUlf Hansson if (IS_ERR(pdev)) {
443166bf835SUlf Hansson platform_driver_unregister(&psci_cpuidle_driver);
444166bf835SUlf Hansson return PTR_ERR(pdev);
445166bf835SUlf Hansson }
446166bf835SUlf Hansson
447166bf835SUlf Hansson return 0;
448166bf835SUlf Hansson }
44981d549e0SLorenzo Pieralisi device_initcall(psci_idle_init);
450