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1// SPDX-License-Identifier: GPL-2.0-only2/*3 *4 * Copyright (C) 2015 ARM Limited5 */6 7#define pr_fmt(fmt) "psci: " fmt8 9#include <linux/acpi.h>10#include <linux/arm-smccc.h>11#include <linux/cpuidle.h>12#include <linux/debugfs.h>13#include <linux/errno.h>14#include <linux/linkage.h>15#include <linux/of.h>16#include <linux/pm.h>17#include <linux/printk.h>18#include <linux/psci.h>19#include <linux/reboot.h>20#include <linux/slab.h>21#include <linux/suspend.h>22 23#include <uapi/linux/psci.h>24 25#include <asm/cpuidle.h>26#include <asm/cputype.h>27#include <asm/hypervisor.h>28#include <asm/system_misc.h>29#include <asm/smp_plat.h>30#include <asm/suspend.h>31 32/*33 * While a 64-bit OS can make calls with SMC32 calling conventions, for some34 * calls it is necessary to use SMC64 to pass or return 64-bit values.35 * For such calls PSCI_FN_NATIVE(version, name) will choose the appropriate36 * (native-width) function ID.37 */38#ifdef CONFIG_64BIT39#define PSCI_FN_NATIVE(version, name)	PSCI_##version##_FN64_##name40#else41#define PSCI_FN_NATIVE(version, name)	PSCI_##version##_FN_##name42#endif43 44/*45 * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF46 * calls to its resident CPU, so we must avoid issuing those. We never migrate47 * a Trusted OS even if it claims to be capable of migration -- doing so will48 * require cooperation with a Trusted OS driver.49 */50static int resident_cpu = -1;51struct psci_operations psci_ops;52static enum arm_smccc_conduit psci_conduit = SMCCC_CONDUIT_NONE;53 54bool psci_tos_resident_on(int cpu)55{56	return cpu == resident_cpu;57}58 59typedef unsigned long (psci_fn)(unsigned long, unsigned long,60				unsigned long, unsigned long);61static psci_fn *invoke_psci_fn;62 63static struct psci_0_1_function_ids psci_0_1_function_ids;64 65struct psci_0_1_function_ids get_psci_0_1_function_ids(void)66{67	return psci_0_1_function_ids;68}69 70#define PSCI_0_2_POWER_STATE_MASK		\71				(PSCI_0_2_POWER_STATE_ID_MASK | \72				PSCI_0_2_POWER_STATE_TYPE_MASK | \73				PSCI_0_2_POWER_STATE_AFFL_MASK)74 75#define PSCI_1_0_EXT_POWER_STATE_MASK		\76				(PSCI_1_0_EXT_POWER_STATE_ID_MASK | \77				PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)78 79static u32 psci_cpu_suspend_feature;80static bool psci_system_reset2_supported;81 82static inline bool psci_has_ext_power_state(void)83{84	return psci_cpu_suspend_feature &85				PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;86}87 88bool psci_has_osi_support(void)89{90	return psci_cpu_suspend_feature & PSCI_1_0_OS_INITIATED;91}92 93static inline bool psci_power_state_loses_context(u32 state)94{95	const u32 mask = psci_has_ext_power_state() ?96					PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :97					PSCI_0_2_POWER_STATE_TYPE_MASK;98 99	return state & mask;100}101 102bool psci_power_state_is_valid(u32 state)103{104	const u32 valid_mask = psci_has_ext_power_state() ?105			       PSCI_1_0_EXT_POWER_STATE_MASK :106			       PSCI_0_2_POWER_STATE_MASK;107 108	return !(state & ~valid_mask);109}110 111static __always_inline unsigned long112__invoke_psci_fn_hvc(unsigned long function_id,113		     unsigned long arg0, unsigned long arg1,114		     unsigned long arg2)115{116	struct arm_smccc_res res;117 118	arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);119	return res.a0;120}121 122static __always_inline unsigned long123__invoke_psci_fn_smc(unsigned long function_id,124		     unsigned long arg0, unsigned long arg1,125		     unsigned long arg2)126{127	struct arm_smccc_res res;128 129	arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);130	return res.a0;131}132 133static __always_inline int psci_to_linux_errno(int errno)134{135	switch (errno) {136	case PSCI_RET_SUCCESS:137		return 0;138	case PSCI_RET_NOT_SUPPORTED:139		return -EOPNOTSUPP;140	case PSCI_RET_INVALID_PARAMS:141	case PSCI_RET_INVALID_ADDRESS:142		return -EINVAL;143	case PSCI_RET_DENIED:144		return -EPERM;145	}146 147	return -EINVAL;148}149 150static u32 psci_0_1_get_version(void)151{152	return PSCI_VERSION(0, 1);153}154 155static u32 psci_0_2_get_version(void)156{157	return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);158}159 160int psci_set_osi_mode(bool enable)161{162	unsigned long suspend_mode;163	int err;164 165	suspend_mode = enable ? PSCI_1_0_SUSPEND_MODE_OSI :166			PSCI_1_0_SUSPEND_MODE_PC;167 168	err = invoke_psci_fn(PSCI_1_0_FN_SET_SUSPEND_MODE, suspend_mode, 0, 0);169	if (err < 0)170		pr_info(FW_BUG "failed to set %s mode: %d\n",171				enable ? "OSI" : "PC", err);172	return psci_to_linux_errno(err);173}174 175static __always_inline int176__psci_cpu_suspend(u32 fn, u32 state, unsigned long entry_point)177{178	int err;179 180	err = invoke_psci_fn(fn, state, entry_point, 0);181	return psci_to_linux_errno(err);182}183 184static __always_inline int185psci_0_1_cpu_suspend(u32 state, unsigned long entry_point)186{187	return __psci_cpu_suspend(psci_0_1_function_ids.cpu_suspend,188				  state, entry_point);189}190 191static __always_inline int192psci_0_2_cpu_suspend(u32 state, unsigned long entry_point)193{194	return __psci_cpu_suspend(PSCI_FN_NATIVE(0_2, CPU_SUSPEND),195				  state, entry_point);196}197 198static int __psci_cpu_off(u32 fn, u32 state)199{200	int err;201 202	err = invoke_psci_fn(fn, state, 0, 0);203	return psci_to_linux_errno(err);204}205 206static int psci_0_1_cpu_off(u32 state)207{208	return __psci_cpu_off(psci_0_1_function_ids.cpu_off, state);209}210 211static int psci_0_2_cpu_off(u32 state)212{213	return __psci_cpu_off(PSCI_0_2_FN_CPU_OFF, state);214}215 216static int __psci_cpu_on(u32 fn, unsigned long cpuid, unsigned long entry_point)217{218	int err;219 220	err = invoke_psci_fn(fn, cpuid, entry_point, 0);221	return psci_to_linux_errno(err);222}223 224static int psci_0_1_cpu_on(unsigned long cpuid, unsigned long entry_point)225{226	return __psci_cpu_on(psci_0_1_function_ids.cpu_on, cpuid, entry_point);227}228 229static int psci_0_2_cpu_on(unsigned long cpuid, unsigned long entry_point)230{231	return __psci_cpu_on(PSCI_FN_NATIVE(0_2, CPU_ON), cpuid, entry_point);232}233 234static int __psci_migrate(u32 fn, unsigned long cpuid)235{236	int err;237 238	err = invoke_psci_fn(fn, cpuid, 0, 0);239	return psci_to_linux_errno(err);240}241 242static int psci_0_1_migrate(unsigned long cpuid)243{244	return __psci_migrate(psci_0_1_function_ids.migrate, cpuid);245}246 247static int psci_0_2_migrate(unsigned long cpuid)248{249	return __psci_migrate(PSCI_FN_NATIVE(0_2, MIGRATE), cpuid);250}251 252static int psci_affinity_info(unsigned long target_affinity,253		unsigned long lowest_affinity_level)254{255	return invoke_psci_fn(PSCI_FN_NATIVE(0_2, AFFINITY_INFO),256			      target_affinity, lowest_affinity_level, 0);257}258 259static int psci_migrate_info_type(void)260{261	return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);262}263 264static unsigned long psci_migrate_info_up_cpu(void)265{266	return invoke_psci_fn(PSCI_FN_NATIVE(0_2, MIGRATE_INFO_UP_CPU),267			      0, 0, 0);268}269 270static void set_conduit(enum arm_smccc_conduit conduit)271{272	switch (conduit) {273	case SMCCC_CONDUIT_HVC:274		invoke_psci_fn = __invoke_psci_fn_hvc;275		break;276	case SMCCC_CONDUIT_SMC:277		invoke_psci_fn = __invoke_psci_fn_smc;278		break;279	default:280		WARN(1, "Unexpected PSCI conduit %d\n", conduit);281	}282 283	psci_conduit = conduit;284}285 286static int get_set_conduit_method(const struct device_node *np)287{288	const char *method;289 290	pr_info("probing for conduit method from DT.\n");291 292	if (of_property_read_string(np, "method", &method)) {293		pr_warn("missing \"method\" property\n");294		return -ENXIO;295	}296 297	if (!strcmp("hvc", method)) {298		set_conduit(SMCCC_CONDUIT_HVC);299	} else if (!strcmp("smc", method)) {300		set_conduit(SMCCC_CONDUIT_SMC);301	} else {302		pr_warn("invalid \"method\" property: %s\n", method);303		return -EINVAL;304	}305	return 0;306}307 308static int psci_sys_reset(struct notifier_block *nb, unsigned long action,309			  void *data)310{311	if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&312	    psci_system_reset2_supported) {313		/*314		 * reset_type[31] = 0 (architectural)315		 * reset_type[30:0] = 0 (SYSTEM_WARM_RESET)316		 * cookie = 0 (ignored by the implementation)317		 */318		invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);319	} else {320		invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);321	}322 323	return NOTIFY_DONE;324}325 326static struct notifier_block psci_sys_reset_nb = {327	.notifier_call = psci_sys_reset,328	.priority = 129,329};330 331static void psci_sys_poweroff(void)332{333	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);334}335 336static int psci_features(u32 psci_func_id)337{338	return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,339			      psci_func_id, 0, 0);340}341 342#ifdef CONFIG_DEBUG_FS343 344#define PSCI_ID(ver, _name) \345	{ .fn = PSCI_##ver##_FN_##_name, .name = #_name, }346#define PSCI_ID_NATIVE(ver, _name) \347	{ .fn = PSCI_FN_NATIVE(ver, _name), .name = #_name, }348 349/* A table of all optional functions */350static const struct {351	u32 fn;352	const char *name;353} psci_fn_ids[] = {354	PSCI_ID_NATIVE(0_2, MIGRATE),355	PSCI_ID(0_2, MIGRATE_INFO_TYPE),356	PSCI_ID_NATIVE(0_2, MIGRATE_INFO_UP_CPU),357	PSCI_ID(1_0, CPU_FREEZE),358	PSCI_ID_NATIVE(1_0, CPU_DEFAULT_SUSPEND),359	PSCI_ID_NATIVE(1_0, NODE_HW_STATE),360	PSCI_ID_NATIVE(1_0, SYSTEM_SUSPEND),361	PSCI_ID(1_0, SET_SUSPEND_MODE),362	PSCI_ID_NATIVE(1_0, STAT_RESIDENCY),363	PSCI_ID_NATIVE(1_0, STAT_COUNT),364	PSCI_ID_NATIVE(1_1, SYSTEM_RESET2),365	PSCI_ID(1_1, MEM_PROTECT),366	PSCI_ID_NATIVE(1_1, MEM_PROTECT_CHECK_RANGE),367};368 369static int psci_debugfs_read(struct seq_file *s, void *data)370{371	int feature, type, i;372	u32 ver;373 374	ver = psci_ops.get_version();375	seq_printf(s, "PSCIv%d.%d\n",376		   PSCI_VERSION_MAJOR(ver),377		   PSCI_VERSION_MINOR(ver));378 379	/* PSCI_FEATURES is available only starting from 1.0 */380	if (PSCI_VERSION_MAJOR(ver) < 1)381		return 0;382 383	feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);384	if (feature != PSCI_RET_NOT_SUPPORTED) {385		ver = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);386		seq_printf(s, "SMC Calling Convention v%d.%d\n",387			   PSCI_VERSION_MAJOR(ver),388			   PSCI_VERSION_MINOR(ver));389	} else {390		seq_puts(s, "SMC Calling Convention v1.0 is assumed\n");391	}392 393	feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND));394	if (feature < 0) {395		seq_printf(s, "PSCI_FEATURES(CPU_SUSPEND) error (%d)\n", feature);396	} else {397		seq_printf(s, "OSI is %ssupported\n",398			   (feature & BIT(0)) ? "" : "not ");399		seq_printf(s, "%s StateID format is used\n",400			   (feature & BIT(1)) ? "Extended" : "Original");401	}402 403	type = psci_ops.migrate_info_type();404	if (type == PSCI_0_2_TOS_UP_MIGRATE ||405	    type == PSCI_0_2_TOS_UP_NO_MIGRATE) {406		unsigned long cpuid;407 408		seq_printf(s, "Trusted OS %smigrate capable\n",409			   type == PSCI_0_2_TOS_UP_NO_MIGRATE ? "not " : "");410		cpuid = psci_migrate_info_up_cpu();411		seq_printf(s, "Trusted OS resident on physical CPU 0x%lx (#%d)\n",412			   cpuid, resident_cpu);413	} else if (type == PSCI_0_2_TOS_MP) {414		seq_puts(s, "Trusted OS migration not required\n");415	} else {416		if (type != PSCI_RET_NOT_SUPPORTED)417			seq_printf(s, "MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);418	}419 420	for (i = 0; i < ARRAY_SIZE(psci_fn_ids); i++) {421		feature = psci_features(psci_fn_ids[i].fn);422		if (feature == PSCI_RET_NOT_SUPPORTED)423			continue;424		if (feature < 0)425			seq_printf(s, "PSCI_FEATURES(%s) error (%d)\n",426				   psci_fn_ids[i].name, feature);427		else428			seq_printf(s, "%s is supported\n", psci_fn_ids[i].name);429	}430 431	return 0;432}433 434static int psci_debugfs_open(struct inode *inode, struct file *f)435{436	return single_open(f, psci_debugfs_read, NULL);437}438 439static const struct file_operations psci_debugfs_ops = {440	.owner = THIS_MODULE,441	.open = psci_debugfs_open,442	.release = single_release,443	.read = seq_read,444	.llseek = seq_lseek445};446 447static int __init psci_debugfs_init(void)448{449	if (!invoke_psci_fn || !psci_ops.get_version)450		return 0;451 452	return PTR_ERR_OR_ZERO(debugfs_create_file("psci", 0444, NULL, NULL,453						   &psci_debugfs_ops));454}455late_initcall(psci_debugfs_init)456#endif457 458#ifdef CONFIG_CPU_IDLE459static noinstr int psci_suspend_finisher(unsigned long state)460{461	u32 power_state = state;462	phys_addr_t pa_cpu_resume;463 464	pa_cpu_resume = __pa_symbol_nodebug((unsigned long)cpu_resume);465 466	return psci_ops.cpu_suspend(power_state, pa_cpu_resume);467}468 469int psci_cpu_suspend_enter(u32 state)470{471	int ret;472 473	if (!psci_power_state_loses_context(state)) {474		struct arm_cpuidle_irq_context context;475 476		ct_cpuidle_enter();477		arm_cpuidle_save_irq_context(&context);478		ret = psci_ops.cpu_suspend(state, 0);479		arm_cpuidle_restore_irq_context(&context);480		ct_cpuidle_exit();481	} else {482		/*483		 * ARM64 cpu_suspend() wants to do ct_cpuidle_*() itself.484		 */485		if (!IS_ENABLED(CONFIG_ARM64))486			ct_cpuidle_enter();487 488		ret = cpu_suspend(state, psci_suspend_finisher);489 490		if (!IS_ENABLED(CONFIG_ARM64))491			ct_cpuidle_exit();492	}493 494	return ret;495}496#endif497 498static int psci_system_suspend(unsigned long unused)499{500	int err;501	phys_addr_t pa_cpu_resume = __pa_symbol(cpu_resume);502 503	err = invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),504			      pa_cpu_resume, 0, 0);505	return psci_to_linux_errno(err);506}507 508static int psci_system_suspend_enter(suspend_state_t state)509{510	return cpu_suspend(0, psci_system_suspend);511}512 513static const struct platform_suspend_ops psci_suspend_ops = {514	.valid          = suspend_valid_only_mem,515	.enter          = psci_system_suspend_enter,516};517 518static void __init psci_init_system_reset2(void)519{520	int ret;521 522	ret = psci_features(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2));523 524	if (ret != PSCI_RET_NOT_SUPPORTED)525		psci_system_reset2_supported = true;526}527 528static void __init psci_init_system_suspend(void)529{530	int ret;531 532	if (!IS_ENABLED(CONFIG_SUSPEND))533		return;534 535	ret = psci_features(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND));536 537	if (ret != PSCI_RET_NOT_SUPPORTED)538		suspend_set_ops(&psci_suspend_ops);539}540 541static void __init psci_init_cpu_suspend(void)542{543	int feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND));544 545	if (feature != PSCI_RET_NOT_SUPPORTED)546		psci_cpu_suspend_feature = feature;547}548 549/*550 * Detect the presence of a resident Trusted OS which may cause CPU_OFF to551 * return DENIED (which would be fatal).552 */553static void __init psci_init_migrate(void)554{555	unsigned long cpuid;556	int type, cpu = -1;557 558	type = psci_ops.migrate_info_type();559 560	if (type == PSCI_0_2_TOS_MP) {561		pr_info("Trusted OS migration not required\n");562		return;563	}564 565	if (type == PSCI_RET_NOT_SUPPORTED) {566		pr_info("MIGRATE_INFO_TYPE not supported.\n");567		return;568	}569 570	if (type != PSCI_0_2_TOS_UP_MIGRATE &&571	    type != PSCI_0_2_TOS_UP_NO_MIGRATE) {572		pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);573		return;574	}575 576	cpuid = psci_migrate_info_up_cpu();577	if (cpuid & ~MPIDR_HWID_BITMASK) {578		pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",579			cpuid);580		return;581	}582 583	cpu = get_logical_index(cpuid);584	resident_cpu = cpu >= 0 ? cpu : -1;585 586	pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);587}588 589static void __init psci_init_smccc(void)590{591	u32 ver = ARM_SMCCC_VERSION_1_0;592	int feature;593 594	feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);595 596	if (feature != PSCI_RET_NOT_SUPPORTED) {597		u32 ret;598		ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);599		if (ret >= ARM_SMCCC_VERSION_1_1) {600			arm_smccc_version_init(ret, psci_conduit);601			ver = ret;602		}603	}604 605	/*606	 * Conveniently, the SMCCC and PSCI versions are encoded the607	 * same way. No, this isn't accidental.608	 */609	pr_info("SMC Calling Convention v%d.%d\n",610		PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver));611 612}613 614static void __init psci_0_2_set_functions(void)615{616	pr_info("Using standard PSCI v0.2 function IDs\n");617 618	psci_ops = (struct psci_operations){619		.get_version = psci_0_2_get_version,620		.cpu_suspend = psci_0_2_cpu_suspend,621		.cpu_off = psci_0_2_cpu_off,622		.cpu_on = psci_0_2_cpu_on,623		.migrate = psci_0_2_migrate,624		.affinity_info = psci_affinity_info,625		.migrate_info_type = psci_migrate_info_type,626	};627 628	register_restart_handler(&psci_sys_reset_nb);629 630	pm_power_off = psci_sys_poweroff;631}632 633/*634 * Probe function for PSCI firmware versions >= 0.2635 */636static int __init psci_probe(void)637{638	u32 ver = psci_0_2_get_version();639 640	pr_info("PSCIv%d.%d detected in firmware.\n",641			PSCI_VERSION_MAJOR(ver),642			PSCI_VERSION_MINOR(ver));643 644	if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {645		pr_err("Conflicting PSCI version detected.\n");646		return -EINVAL;647	}648 649	psci_0_2_set_functions();650 651	psci_init_migrate();652 653	if (PSCI_VERSION_MAJOR(ver) >= 1) {654		psci_init_smccc();655		psci_init_cpu_suspend();656		psci_init_system_suspend();657		psci_init_system_reset2();658		kvm_init_hyp_services();659	}660 661	return 0;662}663 664typedef int (*psci_initcall_t)(const struct device_node *);665 666/*667 * PSCI init function for PSCI versions >=0.2668 *669 * Probe based on PSCI PSCI_VERSION function670 */671static int __init psci_0_2_init(const struct device_node *np)672{673	int err;674 675	err = get_set_conduit_method(np);676	if (err)677		return err;678 679	/*680	 * Starting with v0.2, the PSCI specification introduced a call681	 * (PSCI_VERSION) that allows probing the firmware version, so682	 * that PSCI function IDs and version specific initialization683	 * can be carried out according to the specific version reported684	 * by firmware685	 */686	return psci_probe();687}688 689/*690 * PSCI < v0.2 get PSCI Function IDs via DT.691 */692static int __init psci_0_1_init(const struct device_node *np)693{694	u32 id;695	int err;696 697	err = get_set_conduit_method(np);698	if (err)699		return err;700 701	pr_info("Using PSCI v0.1 Function IDs from DT\n");702 703	psci_ops.get_version = psci_0_1_get_version;704 705	if (!of_property_read_u32(np, "cpu_suspend", &id)) {706		psci_0_1_function_ids.cpu_suspend = id;707		psci_ops.cpu_suspend = psci_0_1_cpu_suspend;708	}709 710	if (!of_property_read_u32(np, "cpu_off", &id)) {711		psci_0_1_function_ids.cpu_off = id;712		psci_ops.cpu_off = psci_0_1_cpu_off;713	}714 715	if (!of_property_read_u32(np, "cpu_on", &id)) {716		psci_0_1_function_ids.cpu_on = id;717		psci_ops.cpu_on = psci_0_1_cpu_on;718	}719 720	if (!of_property_read_u32(np, "migrate", &id)) {721		psci_0_1_function_ids.migrate = id;722		psci_ops.migrate = psci_0_1_migrate;723	}724 725	return 0;726}727 728static int __init psci_1_0_init(const struct device_node *np)729{730	int err;731 732	err = psci_0_2_init(np);733	if (err)734		return err;735 736	if (psci_has_osi_support()) {737		pr_info("OSI mode supported.\n");738 739		/* Default to PC mode. */740		psci_set_osi_mode(false);741	}742 743	return 0;744}745 746static const struct of_device_id psci_of_match[] __initconst = {747	{ .compatible = "arm,psci",	.data = psci_0_1_init},748	{ .compatible = "arm,psci-0.2",	.data = psci_0_2_init},749	{ .compatible = "arm,psci-1.0",	.data = psci_1_0_init},750	{},751};752 753int __init psci_dt_init(void)754{755	struct device_node *np;756	const struct of_device_id *matched_np;757	psci_initcall_t init_fn;758	int ret;759 760	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);761 762	if (!np || !of_device_is_available(np))763		return -ENODEV;764 765	init_fn = (psci_initcall_t)matched_np->data;766	ret = init_fn(np);767 768	of_node_put(np);769	return ret;770}771 772#ifdef CONFIG_ACPI773/*774 * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's775 * explicitly clarified in SBBR776 */777int __init psci_acpi_init(void)778{779	if (!acpi_psci_present()) {780		pr_info("is not implemented in ACPI.\n");781		return -EOPNOTSUPP;782	}783 784	pr_info("probing for conduit method from ACPI.\n");785 786	if (acpi_psci_use_hvc())787		set_conduit(SMCCC_CONDUIT_HVC);788	else789		set_conduit(SMCCC_CONDUIT_SMC);790 791	return psci_probe();792}793#endif794