[deliverable/linux.git] / arch / arm64 / kernel / 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) 2013 ARM Limited
 *
 * Author: Will Deacon <will.deacon@arm.com>
 */

#define pr_fmt(fmt) "psci: " fmt

#include <linux/init.h>
#include <linux/of.h>
#include <linux/smp.h>
#include <linux/reboot.h>
#include <linux/pm.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <uapi/linux/psci.h>

#include <asm/compiler.h>
#include <asm/cpu_ops.h>
#include <asm/errno.h>
#include <asm/psci.h>
#include <asm/smp_plat.h>
#include <asm/suspend.h>
#include <asm/system_misc.h>

#define PSCI_POWER_STATE_TYPE_STANDBY		0
#define PSCI_POWER_STATE_TYPE_POWER_DOWN	1

struct psci_power_state {
	u16	id;
	u8	type;
	u8	affinity_level;
};

struct psci_operations {
	int (*cpu_suspend)(struct psci_power_state state,
			   unsigned long entry_point);
	int (*cpu_off)(struct psci_power_state state);
	int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
	int (*migrate)(unsigned long cpuid);
	int (*affinity_info)(unsigned long target_affinity,
			unsigned long lowest_affinity_level);
	int (*migrate_info_type)(void);
};

static struct psci_operations psci_ops;

static int (*invoke_psci_fn)(u64, u64, u64, u64);
typedef int (*psci_initcall_t)(const struct device_node *);

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

static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state);

static u32 psci_function_id[PSCI_FN_MAX];

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:
		return -EINVAL;
	case PSCI_RET_DENIED:
		return -EPERM;
	};

	return -EINVAL;
}

static u32 psci_power_state_pack(struct psci_power_state state)
{
	return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT)
			& PSCI_0_2_POWER_STATE_ID_MASK) |
		((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT)
		 & PSCI_0_2_POWER_STATE_TYPE_MASK) |
		((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
		 & PSCI_0_2_POWER_STATE_AFFL_MASK);
}

static void psci_power_state_unpack(u32 power_state,
				    struct psci_power_state *state)
{
	state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >>
			PSCI_0_2_POWER_STATE_ID_SHIFT;
	state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >>
			PSCI_0_2_POWER_STATE_TYPE_SHIFT;
	state->affinity_level =
			(power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >>
			PSCI_0_2_POWER_STATE_AFFL_SHIFT;
}

/*
 * The following two functions are invoked via the invoke_psci_fn pointer
 * and will not be inlined, allowing us to piggyback on the AAPCS.
 */
static noinline int __invoke_psci_fn_hvc(u64 function_id, u64 arg0, u64 arg1,
					 u64 arg2)
{
	asm volatile(
			__asmeq("%0", "x0")
			__asmeq("%1", "x1")
			__asmeq("%2", "x2")
			__asmeq("%3", "x3")
			"hvc	#0\n"
		: "+r" (function_id)
		: "r" (arg0), "r" (arg1), "r" (arg2));

	return function_id;
}

static noinline int __invoke_psci_fn_smc(u64 function_id, u64 arg0, u64 arg1,
					 u64 arg2)
{
	asm volatile(
			__asmeq("%0", "x0")
			__asmeq("%1", "x1")
			__asmeq("%2", "x2")
			__asmeq("%3", "x3")
			"smc	#0\n"
		: "+r" (function_id)
		: "r" (arg0), "r" (arg1), "r" (arg2));

	return function_id;
}

static int psci_get_version(void)
{
	int err;

	err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
	return err;
}

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

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

static int psci_cpu_off(struct psci_power_state state)
{
	int err;
	u32 fn, power_state;

	fn = psci_function_id[PSCI_FN_CPU_OFF];
	power_state = psci_power_state_pack(state);
	err = invoke_psci_fn(fn, power_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)
{
	int err;
	u32 fn;

	fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
	err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
	return err;
}

static int psci_migrate_info_type(void)
{
	int err;
	u32 fn;

	fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
	err = invoke_psci_fn(fn, 0, 0, 0);
	return err;
}

static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node,
						 unsigned int cpu)
{
	int i, ret, count = 0;
	struct psci_power_state *psci_states;
	struct device_node *state_node;

	/*
	 * If the PSCI cpu_suspend function hook has not been initialized
	 * idle states must not be enabled, so bail out
	 */
	if (!psci_ops.cpu_suspend)
		return -EOPNOTSUPP;

	/* Count idle states */
	while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
					      count))) {
		count++;
		of_node_put(state_node);
	}

	if (!count)
		return -ENODEV;

	psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
	if (!psci_states)
		return -ENOMEM;

	for (i = 0; i < count; i++) {
		u32 psci_power_state;

		state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);

		ret = of_property_read_u32(state_node,
					   "arm,psci-suspend-param",
					   &psci_power_state);
		if (ret) {
			pr_warn(" * %s missing arm,psci-suspend-param property\n",
				state_node->full_name);
			of_node_put(state_node);
			goto free_mem;
		}

		of_node_put(state_node);
		pr_debug("psci-power-state %#x index %d\n", psci_power_state,
							    i);
		psci_power_state_unpack(psci_power_state, &psci_states[i]);
	}
	/* Idle states parsed correctly, initialize per-cpu pointer */
	per_cpu(psci_power_state, cpu) = psci_states;
	return 0;

free_mem:
	kfree(psci_states);
	return ret;
}

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);
}

/*
 * PSCI Function IDs for v0.2+ are well defined so use
 * standard values.
 */
static int __init psci_0_2_init(struct device_node *np)
{
	int err, ver;

	err = get_set_conduit_method(np);

	if (err)
		goto out_put_node;

	ver = psci_get_version();

	if (ver == PSCI_RET_NOT_SUPPORTED) {
		/* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */
		pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
		err = -EOPNOTSUPP;
		goto out_put_node;
	} else {
		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) {
			err = -EINVAL;
			pr_err("Conflicting PSCI version detected.\n");
			goto out_put_node;
		}
	}

	pr_info("Using standard PSCI v0.2 function IDs\n");
	psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_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_FN64_CPU_ON;
	psci_ops.cpu_on = psci_cpu_on;

	psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN64_MIGRATE;
	psci_ops.migrate = psci_migrate;

	psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN64_AFFINITY_INFO;
	psci_ops.affinity_info = psci_affinity_info;

	psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] =
		PSCI_0_2_FN_MIGRATE_INFO_TYPE;
	psci_ops.migrate_info_type = psci_migrate_info_type;

	arm_pm_restart = psci_sys_reset;

	pm_power_off = psci_sys_poweroff;

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 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_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_SMP

static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu)
{
	return 0;
}

static int __init cpu_psci_cpu_prepare(unsigned int cpu)
{
	if (!psci_ops.cpu_on) {
		pr_err("no cpu_on method, not booting CPU%d\n", cpu);
		return -ENODEV;
	}

	return 0;
}

static int cpu_psci_cpu_boot(unsigned int cpu)
{
	int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_entry));
	if (err)
		pr_err("failed to boot CPU%d (%d)\n", cpu, err);

	return err;
}

#ifdef CONFIG_HOTPLUG_CPU
static int cpu_psci_cpu_disable(unsigned int cpu)
{
	/* Fail early if we don't have CPU_OFF support */
	if (!psci_ops.cpu_off)
		return -EOPNOTSUPP;
	return 0;
}

static void cpu_psci_cpu_die(unsigned int cpu)
{
	int ret;
	/*
	 * There are no known implementations of PSCI actually using the
	 * power state field, pass a sensible default for now.
	 */
	struct psci_power_state state = {
		.type = PSCI_POWER_STATE_TYPE_POWER_DOWN,
	};

	ret = psci_ops.cpu_off(state);

	pr_crit("unable to power off CPU%u (%d)\n", cpu, ret);
}

static int cpu_psci_cpu_kill(unsigned int cpu)
{
	int err, i;

	if (!psci_ops.affinity_info)
		return 1;
	/*
	 * cpu_kill could race with cpu_die and we can
	 * potentially end up declaring this cpu undead
	 * while it is dying. So, try again a few times.
	 */

	for (i = 0; i < 10; i++) {
		err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
		if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
			pr_info("CPU%d killed.\n", cpu);
			return 1;
		}

		msleep(10);
		pr_info("Retrying again to check for CPU kill\n");
	}

	pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
			cpu, err);
	/* Make op_cpu_kill() fail. */
	return 0;
}
#endif
#endif

static int psci_suspend_finisher(unsigned long index)
{
	struct psci_power_state *state = __get_cpu_var(psci_power_state);

	return psci_ops.cpu_suspend(state[index - 1],
				    virt_to_phys(cpu_resume));
}

static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
{
	int ret;
	struct psci_power_state *state = __get_cpu_var(psci_power_state);
	/*
	 * idle state index 0 corresponds to wfi, should never be called
	 * from the cpu_suspend operations
	 */
	if (WARN_ON_ONCE(!index))
		return -EINVAL;

	if (state->type == PSCI_POWER_STATE_TYPE_STANDBY)
		ret = psci_ops.cpu_suspend(state[index - 1], 0);
	else
		ret = __cpu_suspend(index, psci_suspend_finisher);

	return ret;
}

const struct cpu_operations cpu_psci_ops = {
	.name		= "psci",
#ifdef CONFIG_CPU_IDLE
	.cpu_init_idle	= cpu_psci_cpu_init_idle,
	.cpu_suspend	= cpu_psci_cpu_suspend,
#endif
#ifdef CONFIG_SMP
	.cpu_init	= cpu_psci_cpu_init,
	.cpu_prepare	= cpu_psci_cpu_prepare,
	.cpu_boot	= cpu_psci_cpu_boot,
#ifdef CONFIG_HOTPLUG_CPU
	.cpu_disable	= cpu_psci_cpu_disable,
	.cpu_die	= cpu_psci_cpu_die,
	.cpu_kill	= cpu_psci_cpu_kill,
#endif
#endif
};
Commit	Line	Data
e790f1de WD	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) 2013 ARM Limited
	12	*
	13	* Author: Will Deacon <will.deacon@arm.com>
	14	*/
	15
	16	#define pr_fmt(fmt) "psci: " fmt
	17
	18	#include <linux/init.h>
	19	#include <linux/of.h>
00ef54bb	20	#include <linux/smp.h>
e71246a2 AC	21	#include <linux/reboot.h>
e71246a2 AC	22	#include <linux/pm.h>
c814ca02	23	#include <linux/delay.h>
18910ab0	24	#include <linux/slab.h>
e71246a2	25	#include <uapi/linux/psci.h>
e790f1de WD	26
e790f1de WD	27	#include <asm/compiler.h>
cd1aebf5	28	#include <asm/cpu_ops.h>
e790f1de WD	29	#include <asm/errno.h>
e790f1de WD	30	#include <asm/psci.h>
00ef54bb	31	#include <asm/smp_plat.h>
18910ab0	32	#include <asm/suspend.h>
e71246a2	33	#include <asm/system_misc.h>
e790f1de	34
00ef54bb MR	35	#define PSCI_POWER_STATE_TYPE_STANDBY 0
	36	#define PSCI_POWER_STATE_TYPE_POWER_DOWN 1
	37
	38	struct psci_power_state {
	39	u16 id;
	40	u8 type;
	41	u8 affinity_level;
	42	};
	43
	44	struct psci_operations {
	45	int (*cpu_suspend)(struct psci_power_state state,
	46	unsigned long entry_point);
	47	int (*cpu_off)(struct psci_power_state state);
	48	int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
	49	int (*migrate)(unsigned long cpuid);
e71246a2 AC	50	int (*affinity_info)(unsigned long target_affinity,
	51	unsigned long lowest_affinity_level);
	52	int (*migrate_info_type)(void);
00ef54bb MR	53	};
	54
	55	static struct psci_operations psci_ops;
e790f1de WD	56
e790f1de WD	57	static int (*invoke_psci_fn)(u64, u64, u64, u64);
e71246a2	58	typedef int (psci_initcall_t)(const struct device_node );
e790f1de WD	59
	60	enum psci_function {
	61	PSCI_FN_CPU_SUSPEND,
	62	PSCI_FN_CPU_ON,
	63	PSCI_FN_CPU_OFF,
	64	PSCI_FN_MIGRATE,
e71246a2 AC	65	PSCI_FN_AFFINITY_INFO,
e71246a2 AC	66	PSCI_FN_MIGRATE_INFO_TYPE,
e790f1de WD	67	PSCI_FN_MAX,
	68	};
	69
18910ab0 LP	70	static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state);
18910ab0 LP	71
e790f1de WD	72	static u32 psci_function_id[PSCI_FN_MAX];
e790f1de WD	73
e790f1de WD	74	static int psci_to_linux_errno(int errno)
	75	{
	76	switch (errno) {
	77	case PSCI_RET_SUCCESS:
	78	return 0;
e71246a2	79	case PSCI_RET_NOT_SUPPORTED:
e790f1de	80	return -EOPNOTSUPP;
e71246a2	81	case PSCI_RET_INVALID_PARAMS:
e790f1de	82	return -EINVAL;
e71246a2	83	case PSCI_RET_DENIED:
e790f1de WD	84	return -EPERM;
	85	};
	86
	87	return -EINVAL;
	88	}
	89
e790f1de WD	90	static u32 psci_power_state_pack(struct psci_power_state state)
e790f1de WD	91	{
e71246a2 AC	92	return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT)
	93	& PSCI_0_2_POWER_STATE_ID_MASK) \|
	94	((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT)
	95	& PSCI_0_2_POWER_STATE_TYPE_MASK) \|
	96	((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
	97	& PSCI_0_2_POWER_STATE_AFFL_MASK);
e790f1de WD	98	}
e790f1de WD	99
18910ab0 LP	100	static void psci_power_state_unpack(u32 power_state,
	101	struct psci_power_state *state)
	102	{
	103	state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >>
	104	PSCI_0_2_POWER_STATE_ID_SHIFT;
	105	state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >>
	106	PSCI_0_2_POWER_STATE_TYPE_SHIFT;
	107	state->affinity_level =
	108	(power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >>
	109	PSCI_0_2_POWER_STATE_AFFL_SHIFT;
	110	}
	111
e790f1de WD	112	/*
	113	* The following two functions are invoked via the invoke_psci_fn pointer
	114	* and will not be inlined, allowing us to piggyback on the AAPCS.
	115	*/
	116	static noinline int __invoke_psci_fn_hvc(u64 function_id, u64 arg0, u64 arg1,
	117	u64 arg2)
	118	{
	119	asm volatile(
	120	__asmeq("%0", "x0")
	121	__asmeq("%1", "x1")
	122	__asmeq("%2", "x2")
	123	__asmeq("%3", "x3")
	124	"hvc #0\n"
	125	: "+r" (function_id)
	126	: "r" (arg0), "r" (arg1), "r" (arg2));
	127
	128	return function_id;
	129	}
	130
	131	static noinline int __invoke_psci_fn_smc(u64 function_id, u64 arg0, u64 arg1,
	132	u64 arg2)
	133	{
	134	asm volatile(
	135	__asmeq("%0", "x0")
	136	__asmeq("%1", "x1")
	137	__asmeq("%2", "x2")
	138	__asmeq("%3", "x3")
	139	"smc #0\n"
	140	: "+r" (function_id)
	141	: "r" (arg0), "r" (arg1), "r" (arg2));
	142
	143	return function_id;
	144	}
	145
e71246a2 AC	146	static int psci_get_version(void)
	147	{
	148	int err;
	149
	150	err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
	151	return err;
	152	}
	153
e790f1de WD	154	static int psci_cpu_suspend(struct psci_power_state state,
	155	unsigned long entry_point)
	156	{
	157	int err;
	158	u32 fn, power_state;
	159
	160	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
	161	power_state = psci_power_state_pack(state);
	162	err = invoke_psci_fn(fn, power_state, entry_point, 0);
	163	return psci_to_linux_errno(err);
	164	}
	165
	166	static int psci_cpu_off(struct psci_power_state state)
	167	{
	168	int err;
	169	u32 fn, power_state;
	170
	171	fn = psci_function_id[PSCI_FN_CPU_OFF];
	172	power_state = psci_power_state_pack(state);
	173	err = invoke_psci_fn(fn, power_state, 0, 0);
	174	return psci_to_linux_errno(err);
	175	}
	176
	177	static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
	178	{
	179	int err;
	180	u32 fn;
	181
	182	fn = psci_function_id[PSCI_FN_CPU_ON];
	183	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
	184	return psci_to_linux_errno(err);
	185	}
	186
	187	static int psci_migrate(unsigned long cpuid)
	188	{
	189	int err;
	190	u32 fn;
	191
	192	fn = psci_function_id[PSCI_FN_MIGRATE];
	193	err = invoke_psci_fn(fn, cpuid, 0, 0);
	194	return psci_to_linux_errno(err);
	195	}
	196
e71246a2 AC	197	static int psci_affinity_info(unsigned long target_affinity,
	198	unsigned long lowest_affinity_level)
	199	{
	200	int err;
	201	u32 fn;
e790f1de	202
e71246a2 AC	203	fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
	204	err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
	205	return err;
	206	}
	207
	208	static int psci_migrate_info_type(void)
e790f1de	209	{
e71246a2 AC	210	int err;
e71246a2 AC	211	u32 fn;
e790f1de	212
e71246a2 AC	213	fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
	214	err = invoke_psci_fn(fn, 0, 0, 0);
	215	return err;
	216	}
e790f1de	217
18910ab0 LP	218	static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node,
	219	unsigned int cpu)
	220	{
	221	int i, ret, count = 0;
	222	struct psci_power_state *psci_states;
	223	struct device_node *state_node;
	224
	225	/*
	226	* If the PSCI cpu_suspend function hook has not been initialized
	227	* idle states must not be enabled, so bail out
	228	*/
	229	if (!psci_ops.cpu_suspend)
	230	return -EOPNOTSUPP;
	231
	232	/* Count idle states */
	233	while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
	234	count))) {
	235	count++;
	236	of_node_put(state_node);
	237	}
	238
	239	if (!count)
	240	return -ENODEV;
	241
	242	psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
	243	if (!psci_states)
	244	return -ENOMEM;
	245
	246	for (i = 0; i < count; i++) {
	247	u32 psci_power_state;
	248
	249	state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
	250
	251	ret = of_property_read_u32(state_node,
	252	"arm,psci-suspend-param",
	253	&psci_power_state);
	254	if (ret) {
	255	pr_warn(" * %s missing arm,psci-suspend-param property\n",
	256	state_node->full_name);
	257	of_node_put(state_node);
	258	goto free_mem;
	259	}
	260
	261	of_node_put(state_node);
	262	pr_debug("psci-power-state %#x index %d\n", psci_power_state,
	263	i);
	264	psci_power_state_unpack(psci_power_state, &psci_states[i]);
	265	}
	266	/* Idle states parsed correctly, initialize per-cpu pointer */
	267	per_cpu(psci_power_state, cpu) = psci_states;
	268	return 0;
	269
	270	free_mem:
	271	kfree(psci_states);
	272	return ret;
	273	}
	274
e71246a2 AC	275	static int get_set_conduit_method(struct device_node *np)
	276	{
	277	const char *method;
	278
	279	pr_info("probing for conduit method from DT.\n");
e790f1de WD	280
e790f1de WD	281	if (of_property_read_string(np, "method", &method)) {
e71246a2 AC	282	pr_warn("missing \"method\" property\n");
e71246a2 AC	283	return -ENXIO;
e790f1de WD	284	}
	285
	286	if (!strcmp("hvc", method)) {
	287	invoke_psci_fn = __invoke_psci_fn_hvc;
	288	} else if (!strcmp("smc", method)) {
	289	invoke_psci_fn = __invoke_psci_fn_smc;
	290	} else {
e71246a2 AC	291	pr_warn("invalid \"method\" property: %s\n", method);
	292	return -EINVAL;
	293	}
	294	return 0;
	295	}
	296
	297	static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
	298	{
	299	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
	300	}
	301
	302	static void psci_sys_poweroff(void)
	303	{
	304	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
	305	}
	306
	307	/*
	308	* PSCI Function IDs for v0.2+ are well defined so use
	309	* standard values.
	310	*/
b9e97ef9	311	static int __init psci_0_2_init(struct device_node *np)
e71246a2 AC	312	{
	313	int err, ver;
	314
	315	err = get_set_conduit_method(np);
	316
	317	if (err)
e790f1de	318	goto out_put_node;
e71246a2 AC	319
	320	ver = psci_get_version();
	321
	322	if (ver == PSCI_RET_NOT_SUPPORTED) {
	323	/* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */
	324	pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
	325	err = -EOPNOTSUPP;
	326	goto out_put_node;
	327	} else {
	328	pr_info("PSCIv%d.%d detected in firmware.\n",
	329	PSCI_VERSION_MAJOR(ver),
	330	PSCI_VERSION_MINOR(ver));
	331
	332	if (PSCI_VERSION_MAJOR(ver) == 0 &&
	333	PSCI_VERSION_MINOR(ver) < 2) {
	334	err = -EINVAL;
	335	pr_err("Conflicting PSCI version detected.\n");
	336	goto out_put_node;
	337	}
e790f1de WD	338	}
e790f1de WD	339
e71246a2 AC	340	pr_info("Using standard PSCI v0.2 function IDs\n");
	341	psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_CPU_SUSPEND;
	342	psci_ops.cpu_suspend = psci_cpu_suspend;
	343
	344	psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
	345	psci_ops.cpu_off = psci_cpu_off;
	346
	347	psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN64_CPU_ON;
	348	psci_ops.cpu_on = psci_cpu_on;
	349
	350	psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN64_MIGRATE;
	351	psci_ops.migrate = psci_migrate;
	352
	353	psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN64_AFFINITY_INFO;
	354	psci_ops.affinity_info = psci_affinity_info;
	355
	356	psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] =
	357	PSCI_0_2_FN_MIGRATE_INFO_TYPE;
	358	psci_ops.migrate_info_type = psci_migrate_info_type;
	359
	360	arm_pm_restart = psci_sys_reset;
	361
	362	pm_power_off = psci_sys_poweroff;
	363
	364	out_put_node:
	365	of_node_put(np);
	366	return err;
	367	}
	368
	369	/*
	370	* PSCI < v0.2 get PSCI Function IDs via DT.
	371	*/
b9e97ef9	372	static int __init psci_0_1_init(struct device_node *np)
e71246a2 AC	373	{
	374	u32 id;
	375	int err;
	376
	377	err = get_set_conduit_method(np);
	378
	379	if (err)
	380	goto out_put_node;
	381
	382	pr_info("Using PSCI v0.1 Function IDs from DT\n");
	383
e790f1de WD	384	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
	385	psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
	386	psci_ops.cpu_suspend = psci_cpu_suspend;
	387	}
	388
	389	if (!of_property_read_u32(np, "cpu_off", &id)) {
	390	psci_function_id[PSCI_FN_CPU_OFF] = id;
	391	psci_ops.cpu_off = psci_cpu_off;
	392	}
	393
	394	if (!of_property_read_u32(np, "cpu_on", &id)) {
	395	psci_function_id[PSCI_FN_CPU_ON] = id;
	396	psci_ops.cpu_on = psci_cpu_on;
	397	}
	398
	399	if (!of_property_read_u32(np, "migrate", &id)) {
	400	psci_function_id[PSCI_FN_MIGRATE] = id;
	401	psci_ops.migrate = psci_migrate;
	402	}
	403
	404	out_put_node:
	405	of_node_put(np);
e71246a2 AC	406	return err;
	407	}
	408
	409	static const struct of_device_id psci_of_match[] __initconst = {
	410	{ .compatible = "arm,psci", .data = psci_0_1_init},
	411	{ .compatible = "arm,psci-0.2", .data = psci_0_2_init},
	412	{},
	413	};
	414
	415	int __init psci_init(void)
	416	{
	417	struct device_node *np;
	418	const struct of_device_id *matched_np;
	419	psci_initcall_t init_fn;
	420
	421	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
	422
	423	if (!np)
	424	return -ENODEV;
	425
	426	init_fn = (psci_initcall_t)matched_np->data;
	427	return init_fn(np);
e790f1de	428	}
00ef54bb MR	429
	430	#ifdef CONFIG_SMP
	431
cd1aebf5	432	static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu)
00ef54bb MR	433	{
	434	return 0;
	435	}
	436
cd1aebf5	437	static int __init cpu_psci_cpu_prepare(unsigned int cpu)
00ef54bb	438	{
00ef54bb MR	439	if (!psci_ops.cpu_on) {
	440	pr_err("no cpu_on method, not booting CPU%d\n", cpu);
	441	return -ENODEV;
	442	}
	443
00ef54bb MR	444	return 0;
	445	}
	446
652af899 MR	447	static int cpu_psci_cpu_boot(unsigned int cpu)
	448	{
	449	int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_entry));
	450	if (err)
288ac26c	451	pr_err("failed to boot CPU%d (%d)\n", cpu, err);
652af899 MR	452
	453	return err;
	454	}
	455
831ccf79 MR	456	#ifdef CONFIG_HOTPLUG_CPU
	457	static int cpu_psci_cpu_disable(unsigned int cpu)
	458	{
	459	/* Fail early if we don't have CPU_OFF support */
	460	if (!psci_ops.cpu_off)
	461	return -EOPNOTSUPP;
	462	return 0;
	463	}
	464
	465	static void cpu_psci_cpu_die(unsigned int cpu)
	466	{
	467	int ret;
	468	/*
	469	* There are no known implementations of PSCI actually using the
	470	* power state field, pass a sensible default for now.
	471	*/
	472	struct psci_power_state state = {
	473	.type = PSCI_POWER_STATE_TYPE_POWER_DOWN,
	474	};
	475
	476	ret = psci_ops.cpu_off(state);
	477
288ac26c	478	pr_crit("unable to power off CPU%u (%d)\n", cpu, ret);
831ccf79	479	}
c814ca02 AC	480
	481	static int cpu_psci_cpu_kill(unsigned int cpu)
	482	{
	483	int err, i;
	484
	485	if (!psci_ops.affinity_info)
	486	return 1;
	487	/*
	488	* cpu_kill could race with cpu_die and we can
	489	* potentially end up declaring this cpu undead
	490	* while it is dying. So, try again a few times.
	491	*/
	492
	493	for (i = 0; i < 10; i++) {
	494	err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
	495	if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
	496	pr_info("CPU%d killed.\n", cpu);
	497	return 1;
	498	}
	499
	500	msleep(10);
	501	pr_info("Retrying again to check for CPU kill\n");
	502	}
	503
	504	pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
	505	cpu, err);
	506	/* Make op_cpu_kill() fail. */
	507	return 0;
	508	}
831ccf79	509	#endif
756854d9	510	#endif
831ccf79	511
18910ab0 LP	512	static int psci_suspend_finisher(unsigned long index)
	513	{
	514	struct psci_power_state *state = __get_cpu_var(psci_power_state);
	515
	516	return psci_ops.cpu_suspend(state[index - 1],
	517	virt_to_phys(cpu_resume));
	518	}
	519
	520	static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
	521	{
	522	int ret;
	523	struct psci_power_state *state = __get_cpu_var(psci_power_state);
	524	/*
	525	* idle state index 0 corresponds to wfi, should never be called
	526	* from the cpu_suspend operations
	527	*/
	528	if (WARN_ON_ONCE(!index))
	529	return -EINVAL;
	530
	531	if (state->type == PSCI_POWER_STATE_TYPE_STANDBY)
	532	ret = psci_ops.cpu_suspend(state[index - 1], 0);
	533	else
	534	ret = __cpu_suspend(index, psci_suspend_finisher);
	535
	536	return ret;
	537	}
	538
cd1aebf5	539	const struct cpu_operations cpu_psci_ops = {
00ef54bb	540	.name = "psci",
18910ab0 LP	541	#ifdef CONFIG_CPU_IDLE
	542	.cpu_init_idle = cpu_psci_cpu_init_idle,
	543	.cpu_suspend = cpu_psci_cpu_suspend,
	544	#endif
756854d9	545	#ifdef CONFIG_SMP
cd1aebf5 MR	546	.cpu_init = cpu_psci_cpu_init,
cd1aebf5 MR	547	.cpu_prepare = cpu_psci_cpu_prepare,
652af899	548	.cpu_boot = cpu_psci_cpu_boot,
831ccf79 MR	549	#ifdef CONFIG_HOTPLUG_CPU
	550	.cpu_disable = cpu_psci_cpu_disable,
	551	.cpu_die = cpu_psci_cpu_die,
c814ca02	552	.cpu_kill = cpu_psci_cpu_kill,
831ccf79	553	#endif
756854d9	554	#endif
00ef54bb MR	555	};
00ef54bb MR	556