[mirror_ubuntu-zesty-kernel.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/cputype.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

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

static bool psci_power_state_is_valid(u32 state)
{
	const u32 valid_mask = PSCI_0_2_POWER_STATE_ID_MASK |
			       PSCI_0_2_POWER_STATE_TYPE_MASK |
			       PSCI_0_2_POWER_STATE_AFFL_MASK;

	return !(state & ~valid_mask);
}

/*
 * 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;

struct psci_operations {
	int (*cpu_suspend)(u32 state, unsigned long entry_point);
	int (*cpu_off)(u32 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;

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 DEFINE_PER_CPU_READ_MOSTLY(u32 *, 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_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_FN64_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_FN64_MIGRATE_INFO_UP_CPU, 0, 0, 0);
}

static int __maybe_unused cpu_psci_cpu_init_idle(unsigned int cpu)
{
	int i, ret, count = 0;
	u32 *psci_states;
	struct device_node *state_node, *cpu_node;

	cpu_node = of_get_cpu_node(cpu, NULL);
	if (!cpu_node)
		return -ENODEV;

	/*
	 * 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 state;

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

		ret = of_property_read_u32(state_node,
					   "arm,psci-suspend-param",
					   &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", state, i);
		if (!psci_power_state_is_valid(state)) {
			pr_warn("Invalid PSCI power state %#x\n", state);
			ret = -EINVAL;
			goto free_mem;
		}
		psci_states[i] = state;
	}
	/* 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);
}

/*
 * 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;

	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_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_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 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

#ifdef CONFIG_SMP

static int __init cpu_psci_cpu_init(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 bool psci_tos_resident_on(int cpu)
{
	return cpu == resident_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;

	/* Trusted OS will deny CPU_OFF */
	if (psci_tos_resident_on(cpu))
		return -EPERM;

	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.
	 */
	u32 state = PSCI_POWER_STATE_TYPE_POWER_DOWN <<
		    PSCI_0_2_POWER_STATE_TYPE_SHIFT;

	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 0;
	/*
	 * 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 0;
		}

		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);
	return -ETIMEDOUT;
}
#endif
#endif

static int psci_suspend_finisher(unsigned long index)
{
	u32 *state = __this_cpu_read(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;
	u32 *state = __this_cpu_read(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 (!psci_power_state_loses_context(state[index - 1]))
		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>
ff3010e6	28	#include <asm/cputype.h>
cd1aebf5	29	#include <asm/cpu_ops.h>
e790f1de WD	30	#include <asm/errno.h>
e790f1de WD	31	#include <asm/psci.h>
00ef54bb	32	#include <asm/smp_plat.h>
18910ab0	33	#include <asm/suspend.h>
e71246a2	34	#include <asm/system_misc.h>
e790f1de	35
00ef54bb MR	36	#define PSCI_POWER_STATE_TYPE_STANDBY 0
	37	#define PSCI_POWER_STATE_TYPE_POWER_DOWN 1
	38
c8cc4273 MR	39	static bool psci_power_state_loses_context(u32 state)
	40	{
	41	return state & PSCI_0_2_POWER_STATE_TYPE_MASK;
	42	}
	43
	44	static bool psci_power_state_is_valid(u32 state)
	45	{
	46	const u32 valid_mask = PSCI_0_2_POWER_STATE_ID_MASK \|
	47	PSCI_0_2_POWER_STATE_TYPE_MASK \|
	48	PSCI_0_2_POWER_STATE_AFFL_MASK;
	49
	50	return !(state & ~valid_mask);
	51	}
00ef54bb	52
ff3010e6 MR	53	/*
	54	* The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
	55	* calls to its resident CPU, so we must avoid issuing those. We never migrate
	56	* a Trusted OS even if it claims to be capable of migration -- doing so will
	57	* require cooperation with a Trusted OS driver.
	58	*/
	59	static int resident_cpu = -1;
	60
00ef54bb	61	struct psci_operations {
c8cc4273 MR	62	int (*cpu_suspend)(u32 state, unsigned long entry_point);
c8cc4273 MR	63	int (*cpu_off)(u32 state);
00ef54bb MR	64	int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
00ef54bb MR	65	int (*migrate)(unsigned long cpuid);
e71246a2 AC	66	int (*affinity_info)(unsigned long target_affinity,
	67	unsigned long lowest_affinity_level);
	68	int (*migrate_info_type)(void);
00ef54bb MR	69	};
	70
	71	static struct psci_operations psci_ops;
e790f1de	72
a06eed3e MR	73	typedef unsigned long (psci_fn)(unsigned long, unsigned long,
	74	unsigned long, unsigned long);
	75	asmlinkage psci_fn __invoke_psci_fn_hvc;
	76	asmlinkage psci_fn __invoke_psci_fn_smc;
	77	static psci_fn *invoke_psci_fn;
f5e0a12c	78
e790f1de WD	79	enum psci_function {
	80	PSCI_FN_CPU_SUSPEND,
	81	PSCI_FN_CPU_ON,
	82	PSCI_FN_CPU_OFF,
	83	PSCI_FN_MIGRATE,
	84	PSCI_FN_MAX,
	85	};
	86
c8cc4273	87	static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
18910ab0	88
e790f1de WD	89	static u32 psci_function_id[PSCI_FN_MAX];
e790f1de WD	90
e790f1de WD	91	static int psci_to_linux_errno(int errno)
	92	{
	93	switch (errno) {
	94	case PSCI_RET_SUCCESS:
	95	return 0;
e71246a2	96	case PSCI_RET_NOT_SUPPORTED:
e790f1de	97	return -EOPNOTSUPP;
e71246a2	98	case PSCI_RET_INVALID_PARAMS:
e790f1de	99	return -EINVAL;
e71246a2	100	case PSCI_RET_DENIED:
e790f1de WD	101	return -EPERM;
	102	};
	103
	104	return -EINVAL;
	105	}
	106
a06eed3e	107	static u32 psci_get_version(void)
e71246a2	108	{
a06eed3e	109	return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
e71246a2 AC	110	}
e71246a2 AC	111
c8cc4273	112	static int psci_cpu_suspend(u32 state, unsigned long entry_point)
e790f1de WD	113	{
e790f1de WD	114	int err;
c8cc4273	115	u32 fn;
e790f1de WD	116
e790f1de WD	117	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
c8cc4273	118	err = invoke_psci_fn(fn, state, entry_point, 0);
e790f1de WD	119	return psci_to_linux_errno(err);
	120	}
	121
c8cc4273	122	static int psci_cpu_off(u32 state)
e790f1de WD	123	{
e790f1de WD	124	int err;
c8cc4273	125	u32 fn;
e790f1de WD	126
e790f1de WD	127	fn = psci_function_id[PSCI_FN_CPU_OFF];
c8cc4273	128	err = invoke_psci_fn(fn, state, 0, 0);
e790f1de WD	129	return psci_to_linux_errno(err);
	130	}
	131
	132	static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
	133	{
	134	int err;
	135	u32 fn;
	136
	137	fn = psci_function_id[PSCI_FN_CPU_ON];
	138	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
	139	return psci_to_linux_errno(err);
	140	}
	141
	142	static int psci_migrate(unsigned long cpuid)
	143	{
	144	int err;
	145	u32 fn;
	146
	147	fn = psci_function_id[PSCI_FN_MIGRATE];
	148	err = invoke_psci_fn(fn, cpuid, 0, 0);
	149	return psci_to_linux_errno(err);
	150	}
	151
e71246a2 AC	152	static int psci_affinity_info(unsigned long target_affinity,
	153	unsigned long lowest_affinity_level)
	154	{
2a7cd0eb MR	155	return invoke_psci_fn(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity,
2a7cd0eb MR	156	lowest_affinity_level, 0);
e71246a2 AC	157	}
	158
	159	static int psci_migrate_info_type(void)
e790f1de	160	{
2a7cd0eb	161	return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
e71246a2	162	}
e790f1de	163
ff3010e6 MR	164	static unsigned long psci_migrate_info_up_cpu(void)
	165	{
	166	return invoke_psci_fn(PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU, 0, 0, 0);
	167	}
	168
819a8826	169	static int __maybe_unused cpu_psci_cpu_init_idle(unsigned int cpu)
18910ab0 LP	170	{
18910ab0 LP	171	int i, ret, count = 0;
c8cc4273	172	u32 *psci_states;
819a8826 LP	173	struct device_node state_node, cpu_node;
	174
	175	cpu_node = of_get_cpu_node(cpu, NULL);
	176	if (!cpu_node)
	177	return -ENODEV;
18910ab0 LP	178
	179	/*
	180	* If the PSCI cpu_suspend function hook has not been initialized
	181	* idle states must not be enabled, so bail out
	182	*/
	183	if (!psci_ops.cpu_suspend)
	184	return -EOPNOTSUPP;
	185
	186	/* Count idle states */
	187	while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
	188	count))) {
	189	count++;
	190	of_node_put(state_node);
	191	}
	192
	193	if (!count)
	194	return -ENODEV;
	195
	196	psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
	197	if (!psci_states)
	198	return -ENOMEM;
	199
	200	for (i = 0; i < count; i++) {
c8cc4273	201	u32 state;
18910ab0 LP	202
	203	state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
	204
	205	ret = of_property_read_u32(state_node,
	206	"arm,psci-suspend-param",
c8cc4273	207	&state);
18910ab0 LP	208	if (ret) {
	209	pr_warn(" * %s missing arm,psci-suspend-param property\n",
	210	state_node->full_name);
	211	of_node_put(state_node);
	212	goto free_mem;
	213	}
	214
	215	of_node_put(state_node);
c8cc4273 MR	216	pr_debug("psci-power-state %#x index %d\n", state, i);
	217	if (!psci_power_state_is_valid(state)) {
	218	pr_warn("Invalid PSCI power state %#x\n", state);
	219	ret = -EINVAL;
	220	goto free_mem;
	221	}
	222	psci_states[i] = state;
18910ab0 LP	223	}
	224	/* Idle states parsed correctly, initialize per-cpu pointer */
	225	per_cpu(psci_power_state, cpu) = psci_states;
	226	return 0;
	227
	228	free_mem:
	229	kfree(psci_states);
	230	return ret;
	231	}
	232
e71246a2 AC	233	static int get_set_conduit_method(struct device_node *np)
	234	{
	235	const char *method;
	236
	237	pr_info("probing for conduit method from DT.\n");
e790f1de WD	238
e790f1de WD	239	if (of_property_read_string(np, "method", &method)) {
e71246a2 AC	240	pr_warn("missing \"method\" property\n");
e71246a2 AC	241	return -ENXIO;
e790f1de WD	242	}
	243
	244	if (!strcmp("hvc", method)) {
	245	invoke_psci_fn = __invoke_psci_fn_hvc;
	246	} else if (!strcmp("smc", method)) {
	247	invoke_psci_fn = __invoke_psci_fn_smc;
	248	} else {
e71246a2 AC	249	pr_warn("invalid \"method\" property: %s\n", method);
	250	return -EINVAL;
	251	}
	252	return 0;
	253	}
	254
	255	static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
	256	{
	257	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
	258	}
	259
	260	static void psci_sys_poweroff(void)
	261	{
	262	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
	263	}
	264
ff3010e6 MR	265	/*
	266	* Detect the presence of a resident Trusted OS which may cause CPU_OFF to
	267	* return DENIED (which would be fatal).
	268	*/
	269	static void __init psci_init_migrate(void)
	270	{
	271	unsigned long cpuid;
	272	int type, cpu;
	273
	274	type = psci_ops.migrate_info_type();
	275
	276	if (type == PSCI_0_2_TOS_MP) {
	277	pr_info("Trusted OS migration not required\n");
	278	return;
	279	}
	280
	281	if (type == PSCI_RET_NOT_SUPPORTED) {
	282	pr_info("MIGRATE_INFO_TYPE not supported.\n");
	283	return;
	284	}
	285
	286	if (type != PSCI_0_2_TOS_UP_MIGRATE &&
	287	type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
	288	pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
	289	return;
	290	}
	291
	292	cpuid = psci_migrate_info_up_cpu();
	293	if (cpuid & ~MPIDR_HWID_BITMASK) {
	294	pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
	295	cpuid);
	296	return;
	297	}
	298
	299	cpu = get_logical_index(cpuid);
	300	resident_cpu = cpu >= 0 ? cpu : -1;
	301
	302	pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
	303	}
	304
7c59a3df GG	305	static void __init psci_0_2_set_functions(void)
	306	{
	307	pr_info("Using standard PSCI v0.2 function IDs\n");
	308	psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_CPU_SUSPEND;
	309	psci_ops.cpu_suspend = psci_cpu_suspend;
	310
	311	psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
	312	psci_ops.cpu_off = psci_cpu_off;
	313
	314	psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN64_CPU_ON;
	315	psci_ops.cpu_on = psci_cpu_on;
	316
	317	psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN64_MIGRATE;
	318	psci_ops.migrate = psci_migrate;
	319
7c59a3df GG	320	psci_ops.affinity_info = psci_affinity_info;
7c59a3df GG	321
7c59a3df GG	322	psci_ops.migrate_info_type = psci_migrate_info_type;
	323
	324	arm_pm_restart = psci_sys_reset;
	325
	326	pm_power_off = psci_sys_poweroff;
	327	}
	328
e71246a2	329	/*
48eb3c8a	330	* Probe function for PSCI firmware versions >= 0.2
e71246a2	331	*/
48eb3c8a	332	static int __init psci_probe(void)
e71246a2	333	{
a06eed3e MR	334	u32 ver = psci_get_version();
	335
	336	pr_info("PSCIv%d.%d detected in firmware.\n",
	337	PSCI_VERSION_MAJOR(ver),
	338	PSCI_VERSION_MINOR(ver));
	339
	340	if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
	341	pr_err("Conflicting PSCI version detected.\n");
	342	return -EINVAL;
e790f1de WD	343	}
e790f1de WD	344
7c59a3df	345	psci_0_2_set_functions();
e71246a2	346
ff3010e6 MR	347	psci_init_migrate();
ff3010e6 MR	348
48eb3c8a LP	349	return 0;
	350	}
	351
a06eed3e MR	352	typedef int (psci_initcall_t)(const struct device_node );
a06eed3e MR	353
48eb3c8a LP	354	/*
	355	* PSCI init function for PSCI versions >=0.2
	356	*
	357	* Probe based on PSCI PSCI_VERSION function
	358	*/
	359	static int __init psci_0_2_init(struct device_node *np)
	360	{
	361	int err;
	362
	363	err = get_set_conduit_method(np);
	364
	365	if (err)
	366	goto out_put_node;
	367	/*
	368	* Starting with v0.2, the PSCI specification introduced a call
	369	* (PSCI_VERSION) that allows probing the firmware version, so
	370	* that PSCI function IDs and version specific initialization
	371	* can be carried out according to the specific version reported
	372	* by firmware
	373	*/
	374	err = psci_probe();
	375
e71246a2 AC	376	out_put_node:
	377	of_node_put(np);
	378	return err;
	379	}
	380
	381	/*
	382	* PSCI < v0.2 get PSCI Function IDs via DT.
	383	*/
b9e97ef9	384	static int __init psci_0_1_init(struct device_node *np)
e71246a2 AC	385	{
	386	u32 id;
	387	int err;
	388
	389	err = get_set_conduit_method(np);
	390
	391	if (err)
	392	goto out_put_node;
	393
	394	pr_info("Using PSCI v0.1 Function IDs from DT\n");
	395
e790f1de WD	396	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
	397	psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
	398	psci_ops.cpu_suspend = psci_cpu_suspend;
	399	}
	400
	401	if (!of_property_read_u32(np, "cpu_off", &id)) {
	402	psci_function_id[PSCI_FN_CPU_OFF] = id;
	403	psci_ops.cpu_off = psci_cpu_off;
	404	}
	405
	406	if (!of_property_read_u32(np, "cpu_on", &id)) {
	407	psci_function_id[PSCI_FN_CPU_ON] = id;
	408	psci_ops.cpu_on = psci_cpu_on;
	409	}
	410
	411	if (!of_property_read_u32(np, "migrate", &id)) {
	412	psci_function_id[PSCI_FN_MIGRATE] = id;
	413	psci_ops.migrate = psci_migrate;
	414	}
	415
	416	out_put_node:
	417	of_node_put(np);
e71246a2 AC	418	return err;
	419	}
	420
	421	static const struct of_device_id psci_of_match[] __initconst = {
	422	{ .compatible = "arm,psci", .data = psci_0_1_init},
	423	{ .compatible = "arm,psci-0.2", .data = psci_0_2_init},
	424	{},
	425	};
	426
7c59a3df	427	int __init psci_dt_init(void)
e71246a2 AC	428	{
	429	struct device_node *np;
	430	const struct of_device_id *matched_np;
	431	psci_initcall_t init_fn;
	432
	433	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
	434
	435	if (!np)
	436	return -ENODEV;
	437
	438	init_fn = (psci_initcall_t)matched_np->data;
	439	return init_fn(np);
e790f1de	440	}
00ef54bb	441
c5a13305	442	#ifdef CONFIG_ACPI
7c59a3df GG	443	/*
	444	* We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
	445	* explicitly clarified in SBBR
	446	*/
	447	int __init psci_acpi_init(void)
	448	{
	449	if (!acpi_psci_present()) {
	450	pr_info("is not implemented in ACPI.\n");
	451	return -EOPNOTSUPP;
	452	}
	453
	454	pr_info("probing for conduit method from ACPI.\n");
	455
	456	if (acpi_psci_use_hvc())
	457	invoke_psci_fn = __invoke_psci_fn_hvc;
	458	else
	459	invoke_psci_fn = __invoke_psci_fn_smc;
	460
d9895571	461	return psci_probe();
7c59a3df	462	}
c5a13305	463	#endif
7c59a3df	464
00ef54bb MR	465	#ifdef CONFIG_SMP
00ef54bb MR	466
819a8826	467	static int __init cpu_psci_cpu_init(unsigned int cpu)
00ef54bb MR	468	{
	469	return 0;
	470	}
	471
cd1aebf5	472	static int __init cpu_psci_cpu_prepare(unsigned int cpu)
00ef54bb	473	{
00ef54bb MR	474	if (!psci_ops.cpu_on) {
	475	pr_err("no cpu_on method, not booting CPU%d\n", cpu);
	476	return -ENODEV;
	477	}
	478
00ef54bb MR	479	return 0;
	480	}
	481
652af899 MR	482	static int cpu_psci_cpu_boot(unsigned int cpu)
	483	{
	484	int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_entry));
	485	if (err)
288ac26c	486	pr_err("failed to boot CPU%d (%d)\n", cpu, err);
652af899 MR	487
	488	return err;
	489	}
	490
831ccf79	491	#ifdef CONFIG_HOTPLUG_CPU
73bf8412 WD	492	static bool psci_tos_resident_on(int cpu)
	493	{
	494	return cpu == resident_cpu;
	495	}
	496
831ccf79 MR	497	static int cpu_psci_cpu_disable(unsigned int cpu)
	498	{
	499	/* Fail early if we don't have CPU_OFF support */
	500	if (!psci_ops.cpu_off)
	501	return -EOPNOTSUPP;
ff3010e6 MR	502
	503	/* Trusted OS will deny CPU_OFF */
	504	if (psci_tos_resident_on(cpu))
	505	return -EPERM;
	506
831ccf79 MR	507	return 0;
	508	}
	509
	510	static void cpu_psci_cpu_die(unsigned int cpu)
	511	{
	512	int ret;
	513	/*
	514	* There are no known implementations of PSCI actually using the
	515	* power state field, pass a sensible default for now.
	516	*/
c8cc4273 MR	517	u32 state = PSCI_POWER_STATE_TYPE_POWER_DOWN <<
c8cc4273 MR	518	PSCI_0_2_POWER_STATE_TYPE_SHIFT;
831ccf79 MR	519
	520	ret = psci_ops.cpu_off(state);
	521
288ac26c	522	pr_crit("unable to power off CPU%u (%d)\n", cpu, ret);
831ccf79	523	}
c814ca02 AC	524
	525	static int cpu_psci_cpu_kill(unsigned int cpu)
	526	{
	527	int err, i;
	528
	529	if (!psci_ops.affinity_info)
6b99c68c	530	return 0;
c814ca02 AC	531	/*
	532	* cpu_kill could race with cpu_die and we can
	533	* potentially end up declaring this cpu undead
	534	* while it is dying. So, try again a few times.
	535	*/
	536
	537	for (i = 0; i < 10; i++) {
	538	err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
	539	if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
	540	pr_info("CPU%d killed.\n", cpu);
6b99c68c	541	return 0;
c814ca02 AC	542	}
	543
	544	msleep(10);
	545	pr_info("Retrying again to check for CPU kill\n");
	546	}
	547
	548	pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
	549	cpu, err);
6b99c68c	550	return -ETIMEDOUT;
c814ca02	551	}
831ccf79	552	#endif
756854d9	553	#endif
831ccf79	554
18910ab0 LP	555	static int psci_suspend_finisher(unsigned long index)
18910ab0 LP	556	{
c8cc4273	557	u32 *state = __this_cpu_read(psci_power_state);
18910ab0 LP	558
	559	return psci_ops.cpu_suspend(state[index - 1],
	560	virt_to_phys(cpu_resume));
	561	}
	562
	563	static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
	564	{
	565	int ret;
c8cc4273	566	u32 *state = __this_cpu_read(psci_power_state);
18910ab0 LP	567	/*
	568	* idle state index 0 corresponds to wfi, should never be called
	569	* from the cpu_suspend operations
	570	*/
	571	if (WARN_ON_ONCE(!index))
	572	return -EINVAL;
	573
c8cc4273	574	if (!psci_power_state_loses_context(state[index - 1]))
18910ab0 LP	575	ret = psci_ops.cpu_suspend(state[index - 1], 0);
18910ab0 LP	576	else
af391b15	577	ret = cpu_suspend(index, psci_suspend_finisher);
18910ab0 LP	578
	579	return ret;
	580	}
	581
cd1aebf5	582	const struct cpu_operations cpu_psci_ops = {
00ef54bb	583	.name = "psci",
18910ab0 LP	584	#ifdef CONFIG_CPU_IDLE
	585	.cpu_init_idle = cpu_psci_cpu_init_idle,
	586	.cpu_suspend = cpu_psci_cpu_suspend,
	587	#endif
756854d9	588	#ifdef CONFIG_SMP
cd1aebf5 MR	589	.cpu_init = cpu_psci_cpu_init,
cd1aebf5 MR	590	.cpu_prepare = cpu_psci_cpu_prepare,
652af899	591	.cpu_boot = cpu_psci_cpu_boot,
831ccf79 MR	592	#ifdef CONFIG_HOTPLUG_CPU
	593	.cpu_disable = cpu_psci_cpu_disable,
	594	.cpu_die = cpu_psci_cpu_die,
c814ca02	595	.cpu_kill = cpu_psci_cpu_kill,
831ccf79	596	#endif
756854d9	597	#endif
00ef54bb MR	598	};
00ef54bb MR	599