[deliverable/linux.git] / drivers / firmware / psci.c

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Copyright (C) 2015 ARM Limited
 */

#define pr_fmt(fmt) "psci: " fmt

#include <linux/errno.h>
#include <linux/linkage.h>
#include <linux/of.h>
#include <linux/pm.h>
#include <linux/printk.h>
#include <linux/psci.h>
#include <linux/reboot.h>

#include <uapi/linux/psci.h>

#include <asm/cputype.h>
#include <asm/system_misc.h>
#include <asm/smp_plat.h>

/*
 * While a 64-bit OS can make calls with SMC32 calling conventions, for some
 * calls it is necessary to use SMC64 to pass or return 64-bit values. For such
 * calls PSCI_0_2_FN_NATIVE(x) will choose the appropriate (native-width)
 * function ID.
 */
#ifdef CONFIG_64BIT
#define PSCI_0_2_FN_NATIVE(name)	PSCI_0_2_FN64_##name
#else
#define PSCI_0_2_FN_NATIVE(name)	PSCI_0_2_FN_##name
#endif

/*
 * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
 * calls to its resident CPU, so we must avoid issuing those. We never migrate
 * a Trusted OS even if it claims to be capable of migration -- doing so will
 * require cooperation with a Trusted OS driver.
 */
static int resident_cpu = -1;

bool psci_tos_resident_on(int cpu)
{
	return cpu == resident_cpu;
}

struct psci_operations psci_ops;

typedef unsigned long (psci_fn)(unsigned long, unsigned long,
				unsigned long, unsigned long);
asmlinkage psci_fn __invoke_psci_fn_hvc;
asmlinkage psci_fn __invoke_psci_fn_smc;
static psci_fn *invoke_psci_fn;

enum psci_function {
	PSCI_FN_CPU_SUSPEND,
	PSCI_FN_CPU_ON,
	PSCI_FN_CPU_OFF,
	PSCI_FN_MIGRATE,
	PSCI_FN_MAX,
};

static u32 psci_function_id[PSCI_FN_MAX];

#define PSCI_0_2_POWER_STATE_MASK		\
				(PSCI_0_2_POWER_STATE_ID_MASK | \
				PSCI_0_2_POWER_STATE_TYPE_MASK | \
				PSCI_0_2_POWER_STATE_AFFL_MASK)

bool psci_power_state_loses_context(u32 state)
{
	return state & PSCI_0_2_POWER_STATE_TYPE_MASK;
}

bool psci_power_state_is_valid(u32 state)
{
	return !(state & ~PSCI_0_2_POWER_STATE_MASK);
}

static int psci_to_linux_errno(int errno)
{
	switch (errno) {
	case PSCI_RET_SUCCESS:
		return 0;
	case PSCI_RET_NOT_SUPPORTED:
		return -EOPNOTSUPP;
	case PSCI_RET_INVALID_PARAMS:
	case PSCI_RET_INVALID_ADDRESS:
		return -EINVAL;
	case PSCI_RET_DENIED:
		return -EPERM;
	};

	return -EINVAL;
}

static u32 psci_get_version(void)
{
	return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
}

static int psci_cpu_suspend(u32 state, unsigned long entry_point)
{
	int err;
	u32 fn;

	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
	err = invoke_psci_fn(fn, state, entry_point, 0);
	return psci_to_linux_errno(err);
}

static int psci_cpu_off(u32 state)
{
	int err;
	u32 fn;

	fn = psci_function_id[PSCI_FN_CPU_OFF];
	err = invoke_psci_fn(fn, state, 0, 0);
	return psci_to_linux_errno(err);
}

static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
{
	int err;
	u32 fn;

	fn = psci_function_id[PSCI_FN_CPU_ON];
	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
	return psci_to_linux_errno(err);
}

static int psci_migrate(unsigned long cpuid)
{
	int err;
	u32 fn;

	fn = psci_function_id[PSCI_FN_MIGRATE];
	err = invoke_psci_fn(fn, cpuid, 0, 0);
	return psci_to_linux_errno(err);
}

static int psci_affinity_info(unsigned long target_affinity,
		unsigned long lowest_affinity_level)
{
	return invoke_psci_fn(PSCI_0_2_FN_NATIVE(AFFINITY_INFO),
			      target_affinity, lowest_affinity_level, 0);
}

static int psci_migrate_info_type(void)
{
	return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
}

static unsigned long psci_migrate_info_up_cpu(void)
{
	return invoke_psci_fn(PSCI_0_2_FN_NATIVE(MIGRATE_INFO_UP_CPU),
			      0, 0, 0);
}

static int get_set_conduit_method(struct device_node *np)
{
	const char *method;

	pr_info("probing for conduit method from DT.\n");

	if (of_property_read_string(np, "method", &method)) {
		pr_warn("missing \"method\" property\n");
		return -ENXIO;
	}

	if (!strcmp("hvc", method)) {
		invoke_psci_fn = __invoke_psci_fn_hvc;
	} else if (!strcmp("smc", method)) {
		invoke_psci_fn = __invoke_psci_fn_smc;
	} else {
		pr_warn("invalid \"method\" property: %s\n", method);
		return -EINVAL;
	}
	return 0;
}

static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
{
	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
}

static void psci_sys_poweroff(void)
{
	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
}

static int __init psci_features(u32 psci_func_id)
{
	return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
			      psci_func_id, 0, 0);
}

/*
 * Detect the presence of a resident Trusted OS which may cause CPU_OFF to
 * return DENIED (which would be fatal).
 */
static void __init psci_init_migrate(void)
{
	unsigned long cpuid;
	int type, cpu = -1;

	type = psci_ops.migrate_info_type();

	if (type == PSCI_0_2_TOS_MP) {
		pr_info("Trusted OS migration not required\n");
		return;
	}

	if (type == PSCI_RET_NOT_SUPPORTED) {
		pr_info("MIGRATE_INFO_TYPE not supported.\n");
		return;
	}

	if (type != PSCI_0_2_TOS_UP_MIGRATE &&
	    type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
		pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
		return;
	}

	cpuid = psci_migrate_info_up_cpu();
	if (cpuid & ~MPIDR_HWID_BITMASK) {
		pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
			cpuid);
		return;
	}

	cpu = get_logical_index(cpuid);
	resident_cpu = cpu >= 0 ? cpu : -1;

	pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
}

static void __init psci_0_2_set_functions(void)
{
	pr_info("Using standard PSCI v0.2 function IDs\n");
	psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN_NATIVE(CPU_SUSPEND);
	psci_ops.cpu_suspend = psci_cpu_suspend;

	psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
	psci_ops.cpu_off = psci_cpu_off;

	psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN_NATIVE(CPU_ON);
	psci_ops.cpu_on = psci_cpu_on;

	psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN_NATIVE(MIGRATE);
	psci_ops.migrate = psci_migrate;

	psci_ops.affinity_info = psci_affinity_info;

	psci_ops.migrate_info_type = psci_migrate_info_type;

	arm_pm_restart = psci_sys_reset;

	pm_power_off = psci_sys_poweroff;
}

/*
 * Probe function for PSCI firmware versions >= 0.2
 */
static int __init psci_probe(void)
{
	u32 ver = psci_get_version();

	pr_info("PSCIv%d.%d detected in firmware.\n",
			PSCI_VERSION_MAJOR(ver),
			PSCI_VERSION_MINOR(ver));

	if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
		pr_err("Conflicting PSCI version detected.\n");
		return -EINVAL;
	}

	psci_0_2_set_functions();

	psci_init_migrate();

	return 0;
}

typedef int (*psci_initcall_t)(const struct device_node *);

/*
 * PSCI init function for PSCI versions >=0.2
 *
 * Probe based on PSCI PSCI_VERSION function
 */
static int __init psci_0_2_init(struct device_node *np)
{
	int err;

	err = get_set_conduit_method(np);

	if (err)
		goto out_put_node;
	/*
	 * Starting with v0.2, the PSCI specification introduced a call
	 * (PSCI_VERSION) that allows probing the firmware version, so
	 * that PSCI function IDs and version specific initialization
	 * can be carried out according to the specific version reported
	 * by firmware
	 */
	err = psci_probe();

out_put_node:
	of_node_put(np);
	return err;
}

/*
 * PSCI < v0.2 get PSCI Function IDs via DT.
 */
static int __init psci_0_1_init(struct device_node *np)
{
	u32 id;
	int err;

	err = get_set_conduit_method(np);

	if (err)
		goto out_put_node;

	pr_info("Using PSCI v0.1 Function IDs from DT\n");

	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
		psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
		psci_ops.cpu_suspend = psci_cpu_suspend;
	}

	if (!of_property_read_u32(np, "cpu_off", &id)) {
		psci_function_id[PSCI_FN_CPU_OFF] = id;
		psci_ops.cpu_off = psci_cpu_off;
	}

	if (!of_property_read_u32(np, "cpu_on", &id)) {
		psci_function_id[PSCI_FN_CPU_ON] = id;
		psci_ops.cpu_on = psci_cpu_on;
	}

	if (!of_property_read_u32(np, "migrate", &id)) {
		psci_function_id[PSCI_FN_MIGRATE] = id;
		psci_ops.migrate = psci_migrate;
	}

out_put_node:
	of_node_put(np);
	return err;
}

static const struct of_device_id const psci_of_match[] __initconst = {
	{ .compatible = "arm,psci",	.data = psci_0_1_init},
	{ .compatible = "arm,psci-0.2",	.data = psci_0_2_init},
	{},
};

int __init psci_dt_init(void)
{
	struct device_node *np;
	const struct of_device_id *matched_np;
	psci_initcall_t init_fn;

	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);

	if (!np)
		return -ENODEV;

	init_fn = (psci_initcall_t)matched_np->data;
	return init_fn(np);
}

#ifdef CONFIG_ACPI
/*
 * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
 * explicitly clarified in SBBR
 */
int __init psci_acpi_init(void)
{
	if (!acpi_psci_present()) {
		pr_info("is not implemented in ACPI.\n");
		return -EOPNOTSUPP;
	}

	pr_info("probing for conduit method from ACPI.\n");

	if (acpi_psci_use_hvc())
		invoke_psci_fn = __invoke_psci_fn_hvc;
	else
		invoke_psci_fn = __invoke_psci_fn_smc;

	return psci_probe();
}
#endif
Commit	Line	Data
bff60792 MR	1	/*
	2	* This program is free software; you can redistribute it and/or modify
	3	* it under the terms of the GNU General Public License version 2 as
	4	* published by the Free Software Foundation.
	5	*
	6	* This program is distributed in the hope that it will be useful,
	7	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	8	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	9	* GNU General Public License for more details.
	10	*
	11	* Copyright (C) 2015 ARM Limited
	12	*/
	13
	14	#define pr_fmt(fmt) "psci: " fmt
	15
	16	#include <linux/errno.h>
	17	#include <linux/linkage.h>
	18	#include <linux/of.h>
	19	#include <linux/pm.h>
	20	#include <linux/printk.h>
	21	#include <linux/psci.h>
	22	#include <linux/reboot.h>
	23
	24	#include <uapi/linux/psci.h>
	25
	26	#include <asm/cputype.h>
	27	#include <asm/system_misc.h>
	28	#include <asm/smp_plat.h>
	29
5211df00 MR	30	/*
	31	* While a 64-bit OS can make calls with SMC32 calling conventions, for some
	32	* calls it is necessary to use SMC64 to pass or return 64-bit values. For such
	33	* calls PSCI_0_2_FN_NATIVE(x) will choose the appropriate (native-width)
	34	* function ID.
	35	*/
	36	#ifdef CONFIG_64BIT
	37	#define PSCI_0_2_FN_NATIVE(name) PSCI_0_2_FN64_##name
	38	#else
	39	#define PSCI_0_2_FN_NATIVE(name) PSCI_0_2_FN_##name
	40	#endif
	41
bff60792 MR	42	/*
	43	* The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
	44	* calls to its resident CPU, so we must avoid issuing those. We never migrate
	45	* a Trusted OS even if it claims to be capable of migration -- doing so will
	46	* require cooperation with a Trusted OS driver.
	47	*/
	48	static int resident_cpu = -1;
	49
	50	bool psci_tos_resident_on(int cpu)
	51	{
	52	return cpu == resident_cpu;
	53	}
	54
	55	struct psci_operations psci_ops;
	56
	57	typedef unsigned long (psci_fn)(unsigned long, unsigned long,
	58	unsigned long, unsigned long);
	59	asmlinkage psci_fn __invoke_psci_fn_hvc;
	60	asmlinkage psci_fn __invoke_psci_fn_smc;
	61	static psci_fn *invoke_psci_fn;
	62
	63	enum psci_function {
	64	PSCI_FN_CPU_SUSPEND,
	65	PSCI_FN_CPU_ON,
	66	PSCI_FN_CPU_OFF,
	67	PSCI_FN_MIGRATE,
	68	PSCI_FN_MAX,
	69	};
	70
	71	static u32 psci_function_id[PSCI_FN_MAX];
	72
068654c2 LP	73	#define PSCI_0_2_POWER_STATE_MASK \
	74	(PSCI_0_2_POWER_STATE_ID_MASK \| \
	75	PSCI_0_2_POWER_STATE_TYPE_MASK \| \
	76	PSCI_0_2_POWER_STATE_AFFL_MASK)
	77
	78	bool psci_power_state_loses_context(u32 state)
	79	{
	80	return state & PSCI_0_2_POWER_STATE_TYPE_MASK;
	81	}
	82
	83	bool psci_power_state_is_valid(u32 state)
	84	{
	85	return !(state & ~PSCI_0_2_POWER_STATE_MASK);
	86	}
	87
bff60792 MR	88	static int psci_to_linux_errno(int errno)
	89	{
	90	switch (errno) {
	91	case PSCI_RET_SUCCESS:
	92	return 0;
	93	case PSCI_RET_NOT_SUPPORTED:
	94	return -EOPNOTSUPP;
	95	case PSCI_RET_INVALID_PARAMS:
2217d7c6	96	case PSCI_RET_INVALID_ADDRESS:
bff60792 MR	97	return -EINVAL;
	98	case PSCI_RET_DENIED:
	99	return -EPERM;
	100	};
	101
	102	return -EINVAL;
	103	}
	104
	105	static u32 psci_get_version(void)
	106	{
	107	return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
	108	}
	109
	110	static int psci_cpu_suspend(u32 state, unsigned long entry_point)
	111	{
	112	int err;
	113	u32 fn;
	114
	115	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
	116	err = invoke_psci_fn(fn, state, entry_point, 0);
	117	return psci_to_linux_errno(err);
	118	}
	119
	120	static int psci_cpu_off(u32 state)
	121	{
	122	int err;
	123	u32 fn;
	124
	125	fn = psci_function_id[PSCI_FN_CPU_OFF];
	126	err = invoke_psci_fn(fn, state, 0, 0);
	127	return psci_to_linux_errno(err);
	128	}
	129
	130	static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
	131	{
	132	int err;
	133	u32 fn;
	134
	135	fn = psci_function_id[PSCI_FN_CPU_ON];
	136	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
	137	return psci_to_linux_errno(err);
	138	}
	139
	140	static int psci_migrate(unsigned long cpuid)
	141	{
	142	int err;
	143	u32 fn;
	144
	145	fn = psci_function_id[PSCI_FN_MIGRATE];
	146	err = invoke_psci_fn(fn, cpuid, 0, 0);
	147	return psci_to_linux_errno(err);
	148	}
	149
	150	static int psci_affinity_info(unsigned long target_affinity,
	151	unsigned long lowest_affinity_level)
	152	{
5211df00 MR	153	return invoke_psci_fn(PSCI_0_2_FN_NATIVE(AFFINITY_INFO),
5211df00 MR	154	target_affinity, lowest_affinity_level, 0);
bff60792 MR	155	}
	156
	157	static int psci_migrate_info_type(void)
	158	{
	159	return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
	160	}
	161
	162	static unsigned long psci_migrate_info_up_cpu(void)
	163	{
5211df00 MR	164	return invoke_psci_fn(PSCI_0_2_FN_NATIVE(MIGRATE_INFO_UP_CPU),
5211df00 MR	165	0, 0, 0);
bff60792 MR	166	}
	167
	168	static int get_set_conduit_method(struct device_node *np)
	169	{
	170	const char *method;
	171
	172	pr_info("probing for conduit method from DT.\n");
	173
	174	if (of_property_read_string(np, "method", &method)) {
	175	pr_warn("missing \"method\" property\n");
	176	return -ENXIO;
	177	}
	178
	179	if (!strcmp("hvc", method)) {
	180	invoke_psci_fn = __invoke_psci_fn_hvc;
	181	} else if (!strcmp("smc", method)) {
	182	invoke_psci_fn = __invoke_psci_fn_smc;
	183	} else {
	184	pr_warn("invalid \"method\" property: %s\n", method);
	185	return -EINVAL;
	186	}
	187	return 0;
	188	}
	189
	190	static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
	191	{
	192	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
	193	}
	194
	195	static void psci_sys_poweroff(void)
	196	{
	197	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
	198	}
	199
5f004e0c LP	200	static int __init psci_features(u32 psci_func_id)
	201	{
	202	return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
	203	psci_func_id, 0, 0);
	204	}
	205
bff60792 MR	206	/*
	207	* Detect the presence of a resident Trusted OS which may cause CPU_OFF to
	208	* return DENIED (which would be fatal).
	209	*/
	210	static void __init psci_init_migrate(void)
	211	{
	212	unsigned long cpuid;
	213	int type, cpu = -1;
	214
	215	type = psci_ops.migrate_info_type();
	216
	217	if (type == PSCI_0_2_TOS_MP) {
	218	pr_info("Trusted OS migration not required\n");
	219	return;
	220	}
	221
	222	if (type == PSCI_RET_NOT_SUPPORTED) {
	223	pr_info("MIGRATE_INFO_TYPE not supported.\n");
	224	return;
	225	}
	226
	227	if (type != PSCI_0_2_TOS_UP_MIGRATE &&
	228	type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
	229	pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
	230	return;
	231	}
	232
	233	cpuid = psci_migrate_info_up_cpu();
	234	if (cpuid & ~MPIDR_HWID_BITMASK) {
	235	pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
	236	cpuid);
	237	return;
	238	}
	239
	240	cpu = get_logical_index(cpuid);
	241	resident_cpu = cpu >= 0 ? cpu : -1;
	242
	243	pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
	244	}
	245
	246	static void __init psci_0_2_set_functions(void)
	247	{
	248	pr_info("Using standard PSCI v0.2 function IDs\n");
5211df00	249	psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN_NATIVE(CPU_SUSPEND);
bff60792 MR	250	psci_ops.cpu_suspend = psci_cpu_suspend;
	251
	252	psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
	253	psci_ops.cpu_off = psci_cpu_off;
	254
5211df00	255	psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN_NATIVE(CPU_ON);
bff60792 MR	256	psci_ops.cpu_on = psci_cpu_on;
bff60792 MR	257
5211df00	258	psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN_NATIVE(MIGRATE);
bff60792 MR	259	psci_ops.migrate = psci_migrate;
	260
	261	psci_ops.affinity_info = psci_affinity_info;
	262
	263	psci_ops.migrate_info_type = psci_migrate_info_type;
	264
	265	arm_pm_restart = psci_sys_reset;
	266
	267	pm_power_off = psci_sys_poweroff;
	268	}
	269
	270	/*
	271	* Probe function for PSCI firmware versions >= 0.2
	272	*/
	273	static int __init psci_probe(void)
	274	{
	275	u32 ver = psci_get_version();
	276
	277	pr_info("PSCIv%d.%d detected in firmware.\n",
	278	PSCI_VERSION_MAJOR(ver),
	279	PSCI_VERSION_MINOR(ver));
	280
	281	if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
	282	pr_err("Conflicting PSCI version detected.\n");
	283	return -EINVAL;
	284	}
	285
	286	psci_0_2_set_functions();
	287
	288	psci_init_migrate();
	289
	290	return 0;
	291	}
	292
	293	typedef int (psci_initcall_t)(const struct device_node );
	294
	295	/*
	296	* PSCI init function for PSCI versions >=0.2
	297	*
	298	* Probe based on PSCI PSCI_VERSION function
	299	*/
	300	static int __init psci_0_2_init(struct device_node *np)
	301	{
	302	int err;
	303
	304	err = get_set_conduit_method(np);
	305
	306	if (err)
	307	goto out_put_node;
	308	/*
	309	* Starting with v0.2, the PSCI specification introduced a call
	310	* (PSCI_VERSION) that allows probing the firmware version, so
	311	* that PSCI function IDs and version specific initialization
	312	* can be carried out according to the specific version reported
	313	* by firmware
	314	*/
	315	err = psci_probe();
	316
	317	out_put_node:
	318	of_node_put(np);
	319	return err;
	320	}
	321
	322	/*
323	* PSCI < v0.2 get PSCI Function IDs via DT.
324	*/
325	static int __init psci_0_1_init(struct device_node *np)
326	{
327	u32 id;
328	int err;
329
330	err = get_set_conduit_method(np);
331
332	if (err)
333	goto out_put_node;
334
335	pr_info("Using PSCI v0.1 Function IDs from DT\n");
336
337	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
338	psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
339	psci_ops.cpu_suspend = psci_cpu_suspend;
340	}
341
342	if (!of_property_read_u32(np, "cpu_off", &id)) {
343	psci_function_id[PSCI_FN_CPU_OFF] = id;
344	psci_ops.cpu_off = psci_cpu_off;
345	}
346
347	if (!of_property_read_u32(np, "cpu_on", &id)) {
348	psci_function_id[PSCI_FN_CPU_ON] = id;
349	psci_ops.cpu_on = psci_cpu_on;
350	}
351
352	if (!of_property_read_u32(np, "migrate", &id)) {
353	psci_function_id[PSCI_FN_MIGRATE] = id;
354	psci_ops.migrate = psci_migrate;
355	}
356
357	out_put_node:
358	of_node_put(np);
359	return err;
360	}
361
c706c7eb	362	static const struct of_device_id const psci_of_match[] __initconst = {
bff60792 MR	363	{ .compatible = "arm,psci", .data = psci_0_1_init},
	364	{ .compatible = "arm,psci-0.2", .data = psci_0_2_init},
	365	{},
	366	};
	367
	368	int __init psci_dt_init(void)
	369	{
	370	struct device_node *np;
	371	const struct of_device_id *matched_np;
	372	psci_initcall_t init_fn;
	373
	374	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
	375
	376	if (!np)
	377	return -ENODEV;
	378
	379	init_fn = (psci_initcall_t)matched_np->data;
	380	return init_fn(np);
	381	}
	382
	383	#ifdef CONFIG_ACPI
	384	/*
	385	* We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
	386	* explicitly clarified in SBBR
	387	*/
	388	int __init psci_acpi_init(void)
	389	{
	390	if (!acpi_psci_present()) {
	391	pr_info("is not implemented in ACPI.\n");
	392	return -EOPNOTSUPP;
	393	}
	394
	395	pr_info("probing for conduit method from ACPI.\n");
	396
	397	if (acpi_psci_use_hvc())
	398	invoke_psci_fn = __invoke_psci_fn_hvc;
	399	else
	400	invoke_psci_fn = __invoke_psci_fn_smc;
	401
	402	return psci_probe();
	403	}
	404	#endif