[linux-2.6-block.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/acpi.h>
#include <linux/arm-smccc.h>
#include <linux/cpuidle.h>
#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 <linux/slab.h>
#include <linux/suspend.h>

#include <uapi/linux/psci.h>

#include <asm/cpuidle.h>
#include <asm/cputype.h>
#include <asm/system_misc.h>
#include <asm/smp_plat.h>
#include <asm/suspend.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_FN_NATIVE(version, name) will choose the appropriate
 * (native-width) function ID.
 */
#ifdef CONFIG_64BIT
#define PSCI_FN_NATIVE(version, name)	PSCI_##version##_FN64_##name
#else
#define PSCI_FN_NATIVE(version, name)	PSCI_##version##_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 = {
	.conduit = PSCI_CONDUIT_NONE,
	.smccc_version = SMCCC_VERSION_1_0,
};

typedef unsigned long (psci_fn)(unsigned long, unsigned long,
				unsigned long, unsigned long);
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)

#define PSCI_1_0_EXT_POWER_STATE_MASK		\
				(PSCI_1_0_EXT_POWER_STATE_ID_MASK | \
				PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)

static u32 psci_cpu_suspend_feature;

static inline bool psci_has_ext_power_state(void)
{
	return psci_cpu_suspend_feature &
				PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
}

static inline bool psci_power_state_loses_context(u32 state)
{
	const u32 mask = psci_has_ext_power_state() ?
					PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :
					PSCI_0_2_POWER_STATE_TYPE_MASK;

	return state & mask;
}

static inline bool psci_power_state_is_valid(u32 state)
{
	const u32 valid_mask = psci_has_ext_power_state() ?
			       PSCI_1_0_EXT_POWER_STATE_MASK :
			       PSCI_0_2_POWER_STATE_MASK;

	return !(state & ~valid_mask);
}

static unsigned long __invoke_psci_fn_hvc(unsigned long function_id,
			unsigned long arg0, unsigned long arg1,
			unsigned long arg2)
{
	struct arm_smccc_res res;

	arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
	return res.a0;
}

static unsigned long __invoke_psci_fn_smc(unsigned long function_id,
			unsigned long arg0, unsigned long arg1,
			unsigned long arg2)
{
	struct arm_smccc_res res;

	arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
	return res.a0;
}

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_FN_NATIVE(0_2, 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_FN_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
			      0, 0, 0);
}

static void set_conduit(enum psci_conduit conduit)
{
	switch (conduit) {
	case PSCI_CONDUIT_HVC:
		invoke_psci_fn = __invoke_psci_fn_hvc;
		break;
	case PSCI_CONDUIT_SMC:
		invoke_psci_fn = __invoke_psci_fn_smc;
		break;
	default:
		WARN(1, "Unexpected PSCI conduit %d\n", conduit);
	}

	psci_ops.conduit = conduit;
}

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)) {
		set_conduit(PSCI_CONDUIT_HVC);
	} else if (!strcmp("smc", method)) {
		set_conduit(PSCI_CONDUIT_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);
}

#ifdef CONFIG_CPU_IDLE
static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);

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

	/* 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(" * %pOF missing arm,psci-suspend-param property\n",
				state_node);
			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;
}

#ifdef CONFIG_ACPI
#include <acpi/processor.h>

static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu)
{
	int i, count;
	u32 *psci_states;
	struct acpi_lpi_state *lpi;
	struct acpi_processor *pr = per_cpu(processors, cpu);

	if (unlikely(!pr || !pr->flags.has_lpi))
		return -EINVAL;

	count = pr->power.count - 1;
	if (count <= 0)
		return -ENODEV;

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

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

		lpi = &pr->power.lpi_states[i + 1];
		/*
		 * Only bits[31:0] represent a PSCI power_state while
		 * bits[63:32] must be 0x0 as per ARM ACPI FFH Specification
		 */
		state = lpi->address;
		if (!psci_power_state_is_valid(state)) {
			pr_warn("Invalid PSCI power state %#x\n", state);
			kfree(psci_states);
			return -EINVAL;
		}
		psci_states[i] = state;
	}
	/* Idle states parsed correctly, initialize per-cpu pointer */
	per_cpu(psci_power_state, cpu) = psci_states;
	return 0;
}
#else
static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu)
{
	return -EINVAL;
}
#endif

int psci_cpu_init_idle(unsigned int cpu)
{
	struct device_node *cpu_node;
	int ret;

	/*
	 * 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;

	if (!acpi_disabled)
		return psci_acpi_cpu_init_idle(cpu);

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

	ret = psci_dt_cpu_init_idle(cpu_node, cpu);

	of_node_put(cpu_node);

	return ret;
}

static int psci_suspend_finisher(unsigned long index)
{
	u32 *state = __this_cpu_read(psci_power_state);

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

int psci_cpu_suspend_enter(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;
}

/* ARM specific CPU idle operations */
#ifdef CONFIG_ARM
static const struct cpuidle_ops psci_cpuidle_ops __initconst = {
	.suspend = psci_cpu_suspend_enter,
	.init = psci_dt_cpu_init_idle,
};

CPUIDLE_METHOD_OF_DECLARE(psci, "psci", &psci_cpuidle_ops);
#endif
#endif

static int psci_system_suspend(unsigned long unused)
{
	return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
			      __pa_symbol(cpu_resume), 0, 0);
}

static int psci_system_suspend_enter(suspend_state_t state)
{
	return cpu_suspend(0, psci_system_suspend);
}

static const struct platform_suspend_ops psci_suspend_ops = {
	.valid          = suspend_valid_only_mem,
	.enter          = psci_system_suspend_enter,
};

static void __init psci_init_system_suspend(void)
{
	int ret;

	if (!IS_ENABLED(CONFIG_SUSPEND))
		return;

	ret = psci_features(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND));

	if (ret != PSCI_RET_NOT_SUPPORTED)
		suspend_set_ops(&psci_suspend_ops);
}

static void __init psci_init_cpu_suspend(void)
{
	int feature = psci_features(psci_function_id[PSCI_FN_CPU_SUSPEND]);

	if (feature != PSCI_RET_NOT_SUPPORTED)
		psci_cpu_suspend_feature = feature;
}

/*
 * 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_init_smccc(void)
{
	u32 ver = ARM_SMCCC_VERSION_1_0;
	int feature;

	feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);

	if (feature != PSCI_RET_NOT_SUPPORTED) {
		u32 ret;
		ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
		if (ret == ARM_SMCCC_VERSION_1_1) {
			psci_ops.smccc_version = SMCCC_VERSION_1_1;
			ver = ret;
		}
	}

	/*
	 * Conveniently, the SMCCC and PSCI versions are encoded the
	 * same way. No, this isn't accidental.
	 */
	pr_info("SMC Calling Convention v%d.%d\n",
		PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver));

}

static void __init psci_0_2_set_functions(void)
{
	pr_info("Using standard PSCI v0.2 function IDs\n");
	psci_ops.get_version = psci_get_version;

	psci_function_id[PSCI_FN_CPU_SUSPEND] =
					PSCI_FN_NATIVE(0_2, 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_FN_NATIVE(0_2, CPU_ON);
	psci_ops.cpu_on = psci_cpu_on;

	psci_function_id[PSCI_FN_MIGRATE] = PSCI_FN_NATIVE(0_2, 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();

	if (PSCI_VERSION_MAJOR(ver) >= 1) {
		psci_init_smccc();
		psci_init_cpu_suspend();
		psci_init_system_suspend();
	}

	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},
	{ .compatible = "arm,psci-1.0",	.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 || !of_device_is_available(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())
		set_conduit(PSCI_CONDUIT_HVC);
	else
		set_conduit(PSCI_CONDUIT_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
c2a25c14	16	#include <linux/acpi.h>
e679660d	17	#include <linux/arm-smccc.h>
8b6f2499	18	#include <linux/cpuidle.h>
bff60792 MR	19	#include <linux/errno.h>
	20	#include <linux/linkage.h>
	21	#include <linux/of.h>
	22	#include <linux/pm.h>
	23	#include <linux/printk.h>
	24	#include <linux/psci.h>
	25	#include <linux/reboot.h>
8b6f2499	26	#include <linux/slab.h>
faf7ec4a	27	#include <linux/suspend.h>
bff60792 MR	28
	29	#include <uapi/linux/psci.h>
	30
8b6f2499	31	#include <asm/cpuidle.h>
bff60792 MR	32	#include <asm/cputype.h>
	33	#include <asm/system_misc.h>
	34	#include <asm/smp_plat.h>
faf7ec4a	35	#include <asm/suspend.h>
bff60792	36
5211df00 MR	37	/*
5211df00 MR	38	* While a 64-bit OS can make calls with SMC32 calling conventions, for some
029180b1 SH	39	* calls it is necessary to use SMC64 to pass or return 64-bit values.
	40	* For such calls PSCI_FN_NATIVE(version, name) will choose the appropriate
	41	* (native-width) function ID.
5211df00 MR	42	*/
5211df00 MR	43	#ifdef CONFIG_64BIT
029180b1	44	#define PSCI_FN_NATIVE(version, name) PSCI_##version##_FN64_##name
5211df00	45	#else
029180b1	46	#define PSCI_FN_NATIVE(version, name) PSCI_##version##_FN_##name
5211df00 MR	47	#endif
5211df00 MR	48
bff60792 MR	49	/*
	50	* The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
	51	* calls to its resident CPU, so we must avoid issuing those. We never migrate
	52	* a Trusted OS even if it claims to be capable of migration -- doing so will
	53	* require cooperation with a Trusted OS driver.
	54	*/
	55	static int resident_cpu = -1;
	56
	57	bool psci_tos_resident_on(int cpu)
	58	{
	59	return cpu == resident_cpu;
	60	}
	61
09a8d6d4 MZ	62	struct psci_operations psci_ops = {
09a8d6d4 MZ	63	.conduit = PSCI_CONDUIT_NONE,
e78eef55	64	.smccc_version = SMCCC_VERSION_1_0,
09a8d6d4	65	};
bff60792 MR	66
	67	typedef unsigned long (psci_fn)(unsigned long, unsigned long,
	68	unsigned long, unsigned long);
bff60792 MR	69	static psci_fn *invoke_psci_fn;
	70
	71	enum psci_function {
	72	PSCI_FN_CPU_SUSPEND,
	73	PSCI_FN_CPU_ON,
	74	PSCI_FN_CPU_OFF,
	75	PSCI_FN_MIGRATE,
	76	PSCI_FN_MAX,
	77	};
	78
	79	static u32 psci_function_id[PSCI_FN_MAX];
	80
068654c2 LP	81	#define PSCI_0_2_POWER_STATE_MASK \
	82	(PSCI_0_2_POWER_STATE_ID_MASK \| \
	83	PSCI_0_2_POWER_STATE_TYPE_MASK \| \
	84	PSCI_0_2_POWER_STATE_AFFL_MASK)
	85
a5c00bb2 LP	86	#define PSCI_1_0_EXT_POWER_STATE_MASK \
	87	(PSCI_1_0_EXT_POWER_STATE_ID_MASK \| \
	88	PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)
	89
	90	static u32 psci_cpu_suspend_feature;
	91
	92	static inline bool psci_has_ext_power_state(void)
	93	{
	94	return psci_cpu_suspend_feature &
	95	PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
	96	}
	97
2b9cf189	98	static inline bool psci_power_state_loses_context(u32 state)
068654c2	99	{
a5c00bb2 LP	100	const u32 mask = psci_has_ext_power_state() ?
	101	PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :
	102	PSCI_0_2_POWER_STATE_TYPE_MASK;
	103
	104	return state & mask;
068654c2 LP	105	}
068654c2 LP	106
2b9cf189	107	static inline bool psci_power_state_is_valid(u32 state)
068654c2	108	{
a5c00bb2 LP	109	const u32 valid_mask = psci_has_ext_power_state() ?
	110	PSCI_1_0_EXT_POWER_STATE_MASK :
	111	PSCI_0_2_POWER_STATE_MASK;
	112
	113	return !(state & ~valid_mask);
068654c2 LP	114	}
068654c2 LP	115
e679660d JW	116	static unsigned long __invoke_psci_fn_hvc(unsigned long function_id,
	117	unsigned long arg0, unsigned long arg1,
	118	unsigned long arg2)
	119	{
	120	struct arm_smccc_res res;
	121
	122	arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
	123	return res.a0;
	124	}
	125
	126	static unsigned long __invoke_psci_fn_smc(unsigned long function_id,
	127	unsigned long arg0, unsigned long arg1,
	128	unsigned long arg2)
	129	{
	130	struct arm_smccc_res res;
	131
	132	arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
	133	return res.a0;
	134	}
	135
bff60792 MR	136	static int psci_to_linux_errno(int errno)
	137	{
	138	switch (errno) {
	139	case PSCI_RET_SUCCESS:
	140	return 0;
	141	case PSCI_RET_NOT_SUPPORTED:
	142	return -EOPNOTSUPP;
	143	case PSCI_RET_INVALID_PARAMS:
2217d7c6	144	case PSCI_RET_INVALID_ADDRESS:
bff60792 MR	145	return -EINVAL;
	146	case PSCI_RET_DENIED:
	147	return -EPERM;
	148	};
	149
	150	return -EINVAL;
	151	}
	152
	153	static u32 psci_get_version(void)
	154	{
	155	return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
	156	}
	157
	158	static int psci_cpu_suspend(u32 state, unsigned long entry_point)
	159	{
	160	int err;
	161	u32 fn;
	162
	163	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
	164	err = invoke_psci_fn(fn, state, entry_point, 0);
	165	return psci_to_linux_errno(err);
	166	}
	167
	168	static int psci_cpu_off(u32 state)
	169	{
	170	int err;
	171	u32 fn;
	172
	173	fn = psci_function_id[PSCI_FN_CPU_OFF];
	174	err = invoke_psci_fn(fn, state, 0, 0);
	175	return psci_to_linux_errno(err);
	176	}
	177
	178	static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
	179	{
	180	int err;
	181	u32 fn;
	182
	183	fn = psci_function_id[PSCI_FN_CPU_ON];
	184	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
	185	return psci_to_linux_errno(err);
	186	}
	187
	188	static int psci_migrate(unsigned long cpuid)
	189	{
	190	int err;
	191	u32 fn;
	192
	193	fn = psci_function_id[PSCI_FN_MIGRATE];
	194	err = invoke_psci_fn(fn, cpuid, 0, 0);
	195	return psci_to_linux_errno(err);
	196	}
	197
	198	static int psci_affinity_info(unsigned long target_affinity,
	199	unsigned long lowest_affinity_level)
	200	{
029180b1	201	return invoke_psci_fn(PSCI_FN_NATIVE(0_2, AFFINITY_INFO),
5211df00	202	target_affinity, lowest_affinity_level, 0);
bff60792 MR	203	}
	204
	205	static int psci_migrate_info_type(void)
	206	{
	207	return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
	208	}
	209
	210	static unsigned long psci_migrate_info_up_cpu(void)
	211	{
029180b1	212	return invoke_psci_fn(PSCI_FN_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
5211df00	213	0, 0, 0);
bff60792 MR	214	}
bff60792 MR	215
09a8d6d4 MZ	216	static void set_conduit(enum psci_conduit conduit)
	217	{
	218	switch (conduit) {
	219	case PSCI_CONDUIT_HVC:
	220	invoke_psci_fn = __invoke_psci_fn_hvc;
	221	break;
	222	case PSCI_CONDUIT_SMC:
	223	invoke_psci_fn = __invoke_psci_fn_smc;
	224	break;
	225	default:
	226	WARN(1, "Unexpected PSCI conduit %d\n", conduit);
	227	}
	228
	229	psci_ops.conduit = conduit;
	230	}
	231
bff60792 MR	232	static int get_set_conduit_method(struct device_node *np)
	233	{
	234	const char *method;
	235
	236	pr_info("probing for conduit method from DT.\n");
	237
	238	if (of_property_read_string(np, "method", &method)) {
	239	pr_warn("missing \"method\" property\n");
	240	return -ENXIO;
	241	}
	242
	243	if (!strcmp("hvc", method)) {
09a8d6d4	244	set_conduit(PSCI_CONDUIT_HVC);
bff60792	245	} else if (!strcmp("smc", method)) {
09a8d6d4	246	set_conduit(PSCI_CONDUIT_SMC);
bff60792 MR	247	} else {
	248	pr_warn("invalid \"method\" property: %s\n", method);
	249	return -EINVAL;
	250	}
	251	return 0;
	252	}
	253
	254	static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
	255	{
	256	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
	257	}
	258
	259	static void psci_sys_poweroff(void)
	260	{
	261	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
	262	}
	263
5f004e0c LP	264	static int __init psci_features(u32 psci_func_id)
	265	{
	266	return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
	267	psci_func_id, 0, 0);
	268	}
	269
8b6f2499 LP	270	#ifdef CONFIG_CPU_IDLE
	271	static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
	272
	273	static int psci_dt_cpu_init_idle(struct device_node *cpu_node, int cpu)
	274	{
	275	int i, ret, count = 0;
	276	u32 *psci_states;
	277	struct device_node *state_node;
	278
8b6f2499 LP	279	/* Count idle states */
	280	while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
	281	count))) {
	282	count++;
	283	of_node_put(state_node);
	284	}
	285
	286	if (!count)
	287	return -ENODEV;
	288
	289	psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
	290	if (!psci_states)
	291	return -ENOMEM;
	292
	293	for (i = 0; i < count; i++) {
	294	u32 state;
	295
	296	state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
	297
	298	ret = of_property_read_u32(state_node,
	299	"arm,psci-suspend-param",
	300	&state);
	301	if (ret) {
9deee319 RH	302	pr_warn(" * %pOF missing arm,psci-suspend-param property\n",
9deee319 RH	303	state_node);
8b6f2499 LP	304	of_node_put(state_node);
	305	goto free_mem;
	306	}
	307
	308	of_node_put(state_node);
	309	pr_debug("psci-power-state %#x index %d\n", state, i);
	310	if (!psci_power_state_is_valid(state)) {
	311	pr_warn("Invalid PSCI power state %#x\n", state);
	312	ret = -EINVAL;
	313	goto free_mem;
	314	}
	315	psci_states[i] = state;
	316	}
	317	/* Idle states parsed correctly, initialize per-cpu pointer */
	318	per_cpu(psci_power_state, cpu) = psci_states;
	319	return 0;
	320
	321	free_mem:
	322	kfree(psci_states);
	323	return ret;
	324	}
	325
c2a25c14 SH	326	#ifdef CONFIG_ACPI
	327	#include <acpi/processor.h>
	328
	329	static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu)
	330	{
	331	int i, count;
	332	u32 *psci_states;
	333	struct acpi_lpi_state *lpi;
	334	struct acpi_processor *pr = per_cpu(processors, cpu);
	335
	336	if (unlikely(!pr \|\| !pr->flags.has_lpi))
	337	return -EINVAL;
	338
	339	count = pr->power.count - 1;
	340	if (count <= 0)
	341	return -ENODEV;
	342
	343	psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
	344	if (!psci_states)
	345	return -ENOMEM;
	346
	347	for (i = 0; i < count; i++) {
	348	u32 state;
	349
	350	lpi = &pr->power.lpi_states[i + 1];
	351	/*
	352	* Only bits[31:0] represent a PSCI power_state while
	353	* bits[63:32] must be 0x0 as per ARM ACPI FFH Specification
	354	*/
	355	state = lpi->address;
	356	if (!psci_power_state_is_valid(state)) {
	357	pr_warn("Invalid PSCI power state %#x\n", state);
	358	kfree(psci_states);
	359	return -EINVAL;
	360	}
	361	psci_states[i] = state;
	362	}
	363	/* Idle states parsed correctly, initialize per-cpu pointer */
	364	per_cpu(psci_power_state, cpu) = psci_states;
	365	return 0;
	366	}
	367	#else
	368	static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu)
	369	{
	370	return -EINVAL;
	371	}
	372	#endif
	373
8b6f2499 LP	374	int psci_cpu_init_idle(unsigned int cpu)
	375	{
	376	struct device_node *cpu_node;
	377	int ret;
	378
c2a25c14 SH	379	/*
	380	* If the PSCI cpu_suspend function hook has not been initialized
	381	* idle states must not be enabled, so bail out
	382	*/
	383	if (!psci_ops.cpu_suspend)
	384	return -EOPNOTSUPP;
	385
	386	if (!acpi_disabled)
	387	return psci_acpi_cpu_init_idle(cpu);
	388
8b6f2499 LP	389	cpu_node = of_get_cpu_node(cpu, NULL);
	390	if (!cpu_node)
	391	return -ENODEV;
	392
	393	ret = psci_dt_cpu_init_idle(cpu_node, cpu);
	394
	395	of_node_put(cpu_node);
	396
	397	return ret;
	398	}
	399
	400	static int psci_suspend_finisher(unsigned long index)
	401	{
	402	u32 *state = __this_cpu_read(psci_power_state);
	403
	404	return psci_ops.cpu_suspend(state[index - 1],
1a08e3d9	405	__pa_symbol(cpu_resume));
8b6f2499 LP	406	}
	407
	408	int psci_cpu_suspend_enter(unsigned long index)
	409	{
	410	int ret;
	411	u32 *state = __this_cpu_read(psci_power_state);
	412	/*
	413	* idle state index 0 corresponds to wfi, should never be called
	414	* from the cpu_suspend operations
	415	*/
	416	if (WARN_ON_ONCE(!index))
	417	return -EINVAL;
	418
	419	if (!psci_power_state_loses_context(state[index - 1]))
	420	ret = psci_ops.cpu_suspend(state[index - 1], 0);
	421	else
	422	ret = cpu_suspend(index, psci_suspend_finisher);
	423
	424	return ret;
	425	}
	426
	427	/* ARM specific CPU idle operations */
	428	#ifdef CONFIG_ARM
5e7c17df	429	static const struct cpuidle_ops psci_cpuidle_ops __initconst = {
8b6f2499 LP	430	.suspend = psci_cpu_suspend_enter,
	431	.init = psci_dt_cpu_init_idle,
	432	};
	433
978fa436	434	CPUIDLE_METHOD_OF_DECLARE(psci, "psci", &psci_cpuidle_ops);
8b6f2499 LP	435	#endif
	436	#endif
	437
faf7ec4a SH	438	static int psci_system_suspend(unsigned long unused)
	439	{
	440	return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
1c33dc10	441	__pa_symbol(cpu_resume), 0, 0);
faf7ec4a SH	442	}
	443
	444	static int psci_system_suspend_enter(suspend_state_t state)
	445	{
	446	return cpu_suspend(0, psci_system_suspend);
	447	}
	448
	449	static const struct platform_suspend_ops psci_suspend_ops = {
	450	.valid = suspend_valid_only_mem,
	451	.enter = psci_system_suspend_enter,
	452	};
	453
	454	static void __init psci_init_system_suspend(void)
	455	{
	456	int ret;
	457
	458	if (!IS_ENABLED(CONFIG_SUSPEND))
	459	return;
	460
	461	ret = psci_features(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND));
	462
	463	if (ret != PSCI_RET_NOT_SUPPORTED)
	464	suspend_set_ops(&psci_suspend_ops);
	465	}
	466
a5c00bb2 LP	467	static void __init psci_init_cpu_suspend(void)
	468	{
	469	int feature = psci_features(psci_function_id[PSCI_FN_CPU_SUSPEND]);
	470
	471	if (feature != PSCI_RET_NOT_SUPPORTED)
	472	psci_cpu_suspend_feature = feature;
	473	}
	474
bff60792 MR	475	/*
	476	* Detect the presence of a resident Trusted OS which may cause CPU_OFF to
	477	* return DENIED (which would be fatal).
	478	*/
	479	static void __init psci_init_migrate(void)
	480	{
	481	unsigned long cpuid;
	482	int type, cpu = -1;
	483
	484	type = psci_ops.migrate_info_type();
	485
	486	if (type == PSCI_0_2_TOS_MP) {
	487	pr_info("Trusted OS migration not required\n");
	488	return;
	489	}
	490
	491	if (type == PSCI_RET_NOT_SUPPORTED) {
	492	pr_info("MIGRATE_INFO_TYPE not supported.\n");
	493	return;
	494	}
	495
	496	if (type != PSCI_0_2_TOS_UP_MIGRATE &&
	497	type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
	498	pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
	499	return;
	500	}
	501
	502	cpuid = psci_migrate_info_up_cpu();
	503	if (cpuid & ~MPIDR_HWID_BITMASK) {
	504	pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
	505	cpuid);
	506	return;
	507	}
	508
	509	cpu = get_logical_index(cpuid);
	510	resident_cpu = cpu >= 0 ? cpu : -1;
	511
	512	pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
	513	}
	514
e78eef55 MZ	515	static void __init psci_init_smccc(void)
	516	{
	517	u32 ver = ARM_SMCCC_VERSION_1_0;
	518	int feature;
	519
	520	feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
	521
	522	if (feature != PSCI_RET_NOT_SUPPORTED) {
	523	u32 ret;
	524	ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
	525	if (ret == ARM_SMCCC_VERSION_1_1) {
	526	psci_ops.smccc_version = SMCCC_VERSION_1_1;
	527	ver = ret;
	528	}
	529	}
	530
	531	/*
	532	* Conveniently, the SMCCC and PSCI versions are encoded the
	533	* same way. No, this isn't accidental.
	534	*/
	535	pr_info("SMC Calling Convention v%d.%d\n",
	536	PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver));
	537
	538	}
	539
bff60792 MR	540	static void __init psci_0_2_set_functions(void)
	541	{
	542	pr_info("Using standard PSCI v0.2 function IDs\n");
d68e3ba5 WD	543	psci_ops.get_version = psci_get_version;
d68e3ba5 WD	544
029180b1 SH	545	psci_function_id[PSCI_FN_CPU_SUSPEND] =
029180b1 SH	546	PSCI_FN_NATIVE(0_2, CPU_SUSPEND);
bff60792 MR	547	psci_ops.cpu_suspend = psci_cpu_suspend;
	548
	549	psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
	550	psci_ops.cpu_off = psci_cpu_off;
	551
029180b1	552	psci_function_id[PSCI_FN_CPU_ON] = PSCI_FN_NATIVE(0_2, CPU_ON);
bff60792 MR	553	psci_ops.cpu_on = psci_cpu_on;
bff60792 MR	554
029180b1	555	psci_function_id[PSCI_FN_MIGRATE] = PSCI_FN_NATIVE(0_2, MIGRATE);
bff60792 MR	556	psci_ops.migrate = psci_migrate;
	557
	558	psci_ops.affinity_info = psci_affinity_info;
	559
	560	psci_ops.migrate_info_type = psci_migrate_info_type;
	561
	562	arm_pm_restart = psci_sys_reset;
	563
	564	pm_power_off = psci_sys_poweroff;
	565	}
	566
	567	/*
	568	* Probe function for PSCI firmware versions >= 0.2
	569	*/
	570	static int __init psci_probe(void)
	571	{
	572	u32 ver = psci_get_version();
	573
	574	pr_info("PSCIv%d.%d detected in firmware.\n",
	575	PSCI_VERSION_MAJOR(ver),
	576	PSCI_VERSION_MINOR(ver));
	577
	578	if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
	579	pr_err("Conflicting PSCI version detected.\n");
	580	return -EINVAL;
	581	}
	582
	583	psci_0_2_set_functions();
	584
	585	psci_init_migrate();
	586
79b04beb	587	if (PSCI_VERSION_MAJOR(ver) >= 1) {
e78eef55	588	psci_init_smccc();
79b04beb LP	589	psci_init_cpu_suspend();
	590	psci_init_system_suspend();
	591	}
faf7ec4a	592
bff60792 MR	593	return 0;
	594	}
	595
	596	typedef int (psci_initcall_t)(const struct device_node );
	597
	598	/*
	599	* PSCI init function for PSCI versions >=0.2
	600	*
	601	* Probe based on PSCI PSCI_VERSION function
	602	*/
	603	static int __init psci_0_2_init(struct device_node *np)
	604	{
	605	int err;
	606
	607	err = get_set_conduit_method(np);
	608
	609	if (err)
	610	goto out_put_node;
	611	/*
	612	* Starting with v0.2, the PSCI specification introduced a call
	613	* (PSCI_VERSION) that allows probing the firmware version, so
	614	* that PSCI function IDs and version specific initialization
	615	* can be carried out according to the specific version reported
	616	* by firmware
	617	*/
	618	err = psci_probe();
	619
	620	out_put_node:
	621	of_node_put(np);
	622	return err;
	623	}
	624
	625	/*
	626	* PSCI < v0.2 get PSCI Function IDs via DT.
	627	*/
	628	static int __init psci_0_1_init(struct device_node *np)
	629	{
	630	u32 id;
	631	int err;
	632
	633	err = get_set_conduit_method(np);
	634
	635	if (err)
	636	goto out_put_node;
	637
	638	pr_info("Using PSCI v0.1 Function IDs from DT\n");
	639
	640	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
	641	psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
	642	psci_ops.cpu_suspend = psci_cpu_suspend;
	643	}
	644
	645	if (!of_property_read_u32(np, "cpu_off", &id)) {
	646	psci_function_id[PSCI_FN_CPU_OFF] = id;
	647	psci_ops.cpu_off = psci_cpu_off;
	648	}
	649
	650	if (!of_property_read_u32(np, "cpu_on", &id)) {
	651	psci_function_id[PSCI_FN_CPU_ON] = id;
	652	psci_ops.cpu_on = psci_cpu_on;
	653	}
	654
	655	if (!of_property_read_u32(np, "migrate", &id)) {
	656	psci_function_id[PSCI_FN_MIGRATE] = id;
657	psci_ops.migrate = psci_migrate;
658	}
659
660	out_put_node:
661	of_node_put(np);
662	return err;
663	}
664
1d2d8de4	665	static const struct of_device_id psci_of_match[] __initconst = {
bff60792 MR	666	{ .compatible = "arm,psci", .data = psci_0_1_init},
bff60792 MR	667	{ .compatible = "arm,psci-0.2", .data = psci_0_2_init},
0fc197c7	668	{ .compatible = "arm,psci-1.0", .data = psci_0_2_init},
bff60792 MR	669	{},
	670	};
	671
	672	int __init psci_dt_init(void)
	673	{
	674	struct device_node *np;
	675	const struct of_device_id *matched_np;
	676	psci_initcall_t init_fn;
	677
	678	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
	679
d09a0011	680	if (!np \|\| !of_device_is_available(np))
bff60792 MR	681	return -ENODEV;
	682
	683	init_fn = (psci_initcall_t)matched_np->data;
	684	return init_fn(np);
	685	}
	686
	687	#ifdef CONFIG_ACPI
	688	/*
	689	* We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
	690	* explicitly clarified in SBBR
	691	*/
	692	int __init psci_acpi_init(void)
	693	{
	694	if (!acpi_psci_present()) {
	695	pr_info("is not implemented in ACPI.\n");
	696	return -EOPNOTSUPP;
	697	}
	698
	699	pr_info("probing for conduit method from ACPI.\n");
	700
	701	if (acpi_psci_use_hvc())
09a8d6d4	702	set_conduit(PSCI_CONDUIT_HVC);
bff60792	703	else
09a8d6d4	704	set_conduit(PSCI_CONDUIT_SMC);
bff60792 MR	705
	706	return psci_probe();
	707	}
	708	#endif