[deliverable/linux.git] / arch / arm / 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) 2012 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/reboot.h>
#include <linux/pm.h>
#include <uapi/linux/psci.h>

#include <asm/compiler.h>
#include <asm/errno.h>
#include <asm/opcodes-sec.h>
#include <asm/opcodes-virt.h>
#include <asm/psci.h>
#include <asm/system_misc.h>

struct psci_operations psci_ops;

static int (*invoke_psci_fn)(u32, u32, u32, u32);
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 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);
}

/*
 * 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(u32 function_id, u32 arg0, u32 arg1,
					 u32 arg2)
{
	asm volatile(
			__asmeq("%0", "r0")
			__asmeq("%1", "r1")
			__asmeq("%2", "r2")
			__asmeq("%3", "r3")
			__HVC(0)
		: "+r" (function_id)
		: "r" (arg0), "r" (arg1), "r" (arg2));

	return function_id;
}

static noinline int __invoke_psci_fn_smc(u32 function_id, u32 arg0, u32 arg1,
					 u32 arg2)
{
	asm volatile(
			__asmeq("%0", "r0")
			__asmeq("%1", "r1")
			__asmeq("%2", "r2")
			__asmeq("%3", "r3")
			__SMC(0)
		: "+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 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 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_FN_CPU_SUSPEND;
	psci_ops.cpu_suspend = psci_cpu_suspend;

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

	psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN_CPU_ON;
	psci_ops.cpu_on = psci_cpu_on;

	psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN_MIGRATE;
	psci_ops.migrate = psci_migrate;

	psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN_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 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);
}
Commit	Line	Data
2bdd424f 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) 2012 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>
e71246a2 AC	20	#include <linux/reboot.h>
	21	#include <linux/pm.h>
	22	#include <uapi/linux/psci.h>
2bdd424f WD	23
	24	#include <asm/compiler.h>
	25	#include <asm/errno.h>
	26	#include <asm/opcodes-sec.h>
	27	#include <asm/opcodes-virt.h>
	28	#include <asm/psci.h>
e71246a2	29	#include <asm/system_misc.h>
2bdd424f WD	30
	31	struct psci_operations psci_ops;
	32
	33	static int (*invoke_psci_fn)(u32, u32, u32, u32);
e71246a2	34	typedef int (psci_initcall_t)(const struct device_node );
2bdd424f WD	35
	36	enum psci_function {
	37	PSCI_FN_CPU_SUSPEND,
	38	PSCI_FN_CPU_ON,
	39	PSCI_FN_CPU_OFF,
	40	PSCI_FN_MIGRATE,
e71246a2 AC	41	PSCI_FN_AFFINITY_INFO,
e71246a2 AC	42	PSCI_FN_MIGRATE_INFO_TYPE,
2bdd424f WD	43	PSCI_FN_MAX,
	44	};
	45
	46	static u32 psci_function_id[PSCI_FN_MAX];
	47
2bdd424f WD	48	static int psci_to_linux_errno(int errno)
	49	{
	50	switch (errno) {
	51	case PSCI_RET_SUCCESS:
	52	return 0;
e71246a2	53	case PSCI_RET_NOT_SUPPORTED:
2bdd424f	54	return -EOPNOTSUPP;
e71246a2	55	case PSCI_RET_INVALID_PARAMS:
2bdd424f	56	return -EINVAL;
e71246a2	57	case PSCI_RET_DENIED:
2bdd424f WD	58	return -EPERM;
	59	};
	60
	61	return -EINVAL;
	62	}
	63
2bdd424f WD	64	static u32 psci_power_state_pack(struct psci_power_state state)
2bdd424f WD	65	{
e71246a2 AC	66	return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT)
	67	& PSCI_0_2_POWER_STATE_ID_MASK) \|
	68	((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT)
	69	& PSCI_0_2_POWER_STATE_TYPE_MASK) \|
	70	((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
	71	& PSCI_0_2_POWER_STATE_AFFL_MASK);
2bdd424f WD	72	}
	73
	74	/*
	75	* The following two functions are invoked via the invoke_psci_fn pointer
	76	* and will not be inlined, allowing us to piggyback on the AAPCS.
	77	*/
	78	static noinline int __invoke_psci_fn_hvc(u32 function_id, u32 arg0, u32 arg1,
	79	u32 arg2)
	80	{
	81	asm volatile(
	82	__asmeq("%0", "r0")
	83	__asmeq("%1", "r1")
	84	__asmeq("%2", "r2")
	85	__asmeq("%3", "r3")
	86	__HVC(0)
	87	: "+r" (function_id)
	88	: "r" (arg0), "r" (arg1), "r" (arg2));
	89
	90	return function_id;
	91	}
	92
	93	static noinline int __invoke_psci_fn_smc(u32 function_id, u32 arg0, u32 arg1,
	94	u32 arg2)
	95	{
	96	asm volatile(
	97	__asmeq("%0", "r0")
	98	__asmeq("%1", "r1")
	99	__asmeq("%2", "r2")
	100	__asmeq("%3", "r3")
	101	__SMC(0)
	102	: "+r" (function_id)
	103	: "r" (arg0), "r" (arg1), "r" (arg2));
	104
	105	return function_id;
	106	}
	107
e71246a2 AC	108	static int psci_get_version(void)
	109	{
	110	int err;
	111
	112	err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
	113	return err;
	114	}
	115
2bdd424f WD	116	static int psci_cpu_suspend(struct psci_power_state state,
	117	unsigned long entry_point)
	118	{
	119	int err;
	120	u32 fn, power_state;
	121
	122	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
	123	power_state = psci_power_state_pack(state);
	124	err = invoke_psci_fn(fn, power_state, entry_point, 0);
	125	return psci_to_linux_errno(err);
	126	}
	127
	128	static int psci_cpu_off(struct psci_power_state state)
	129	{
	130	int err;
	131	u32 fn, power_state;
	132
	133	fn = psci_function_id[PSCI_FN_CPU_OFF];
	134	power_state = psci_power_state_pack(state);
	135	err = invoke_psci_fn(fn, power_state, 0, 0);
	136	return psci_to_linux_errno(err);
	137	}
	138
	139	static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
	140	{
	141	int err;
	142	u32 fn;
	143
	144	fn = psci_function_id[PSCI_FN_CPU_ON];
	145	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
	146	return psci_to_linux_errno(err);
	147	}
	148
	149	static int psci_migrate(unsigned long cpuid)
	150	{
	151	int err;
	152	u32 fn;
	153
	154	fn = psci_function_id[PSCI_FN_MIGRATE];
	155	err = invoke_psci_fn(fn, cpuid, 0, 0);
	156	return psci_to_linux_errno(err);
	157	}
	158
e71246a2 AC	159	static int psci_affinity_info(unsigned long target_affinity,
	160	unsigned long lowest_affinity_level)
	161	{
	162	int err;
	163	u32 fn;
	164
	165	fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
	166	err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
	167	return err;
	168	}
2bdd424f	169
e71246a2	170	static int psci_migrate_info_type(void)
2bdd424f	171	{
e71246a2 AC	172	int err;
e71246a2 AC	173	u32 fn;
2bdd424f	174
e71246a2 AC	175	fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
	176	err = invoke_psci_fn(fn, 0, 0, 0);
	177	return err;
	178	}
	179
	180	static int get_set_conduit_method(struct device_node *np)
	181	{
	182	const char *method;
2bdd424f	183
e71246a2	184	pr_info("probing for conduit method from DT.\n");
2bdd424f WD	185
2bdd424f WD	186	if (of_property_read_string(np, "method", &method)) {
e71246a2 AC	187	pr_warn("missing \"method\" property\n");
e71246a2 AC	188	return -ENXIO;
2bdd424f WD	189	}
	190
	191	if (!strcmp("hvc", method)) {
	192	invoke_psci_fn = __invoke_psci_fn_hvc;
	193	} else if (!strcmp("smc", method)) {
	194	invoke_psci_fn = __invoke_psci_fn_smc;
	195	} else {
e71246a2 AC	196	pr_warn("invalid \"method\" property: %s\n", method);
	197	return -EINVAL;
	198	}
	199	return 0;
	200	}
	201
	202	static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
	203	{
	204	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
	205	}
	206
	207	static void psci_sys_poweroff(void)
	208	{
	209	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
	210	}
	211
	212	/*
	213	* PSCI Function IDs for v0.2+ are well defined so use
	214	* standard values.
	215	*/
	216	static int psci_0_2_init(struct device_node *np)
	217	{
	218	int err, ver;
	219
	220	err = get_set_conduit_method(np);
	221
	222	if (err)
	223	goto out_put_node;
	224
	225	ver = psci_get_version();
	226
	227	if (ver == PSCI_RET_NOT_SUPPORTED) {
	228	/* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */
	229	pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
	230	err = -EOPNOTSUPP;
2bdd424f	231	goto out_put_node;
e71246a2 AC	232	} else {
	233	pr_info("PSCIv%d.%d detected in firmware.\n",
	234	PSCI_VERSION_MAJOR(ver),
	235	PSCI_VERSION_MINOR(ver));
	236
	237	if (PSCI_VERSION_MAJOR(ver) == 0 &&
	238	PSCI_VERSION_MINOR(ver) < 2) {
	239	err = -EINVAL;
	240	pr_err("Conflicting PSCI version detected.\n");
	241	goto out_put_node;
	242	}
2bdd424f WD	243	}
2bdd424f WD	244
e71246a2 AC	245	pr_info("Using standard PSCI v0.2 function IDs\n");
	246	psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN_CPU_SUSPEND;
	247	psci_ops.cpu_suspend = psci_cpu_suspend;
	248
	249	psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
	250	psci_ops.cpu_off = psci_cpu_off;
	251
	252	psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN_CPU_ON;
	253	psci_ops.cpu_on = psci_cpu_on;
	254
	255	psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN_MIGRATE;
	256	psci_ops.migrate = psci_migrate;
	257
	258	psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN_AFFINITY_INFO;
	259	psci_ops.affinity_info = psci_affinity_info;
	260
	261	psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] =
	262	PSCI_0_2_FN_MIGRATE_INFO_TYPE;
	263	psci_ops.migrate_info_type = psci_migrate_info_type;
	264
	265	arm_pm_restart = psci_sys_reset;
	266
	267	pm_power_off = psci_sys_poweroff;
	268
	269	out_put_node:
	270	of_node_put(np);
	271	return err;
	272	}
	273
	274	/*
	275	* PSCI < v0.2 get PSCI Function IDs via DT.
	276	*/
	277	static int psci_0_1_init(struct device_node *np)
	278	{
	279	u32 id;
	280	int err;
	281
	282	err = get_set_conduit_method(np);
	283
	284	if (err)
	285	goto out_put_node;
	286
	287	pr_info("Using PSCI v0.1 Function IDs from DT\n");
	288
2bdd424f WD	289	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
	290	psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
	291	psci_ops.cpu_suspend = psci_cpu_suspend;
	292	}
	293
	294	if (!of_property_read_u32(np, "cpu_off", &id)) {
	295	psci_function_id[PSCI_FN_CPU_OFF] = id;
	296	psci_ops.cpu_off = psci_cpu_off;
	297	}
	298
	299	if (!of_property_read_u32(np, "cpu_on", &id)) {
	300	psci_function_id[PSCI_FN_CPU_ON] = id;
	301	psci_ops.cpu_on = psci_cpu_on;
	302	}
	303
	304	if (!of_property_read_u32(np, "migrate", &id)) {
	305	psci_function_id[PSCI_FN_MIGRATE] = id;
	306	psci_ops.migrate = psci_migrate;
	307	}
	308
	309	out_put_node:
	310	of_node_put(np);
e71246a2 AC	311	return err;
	312	}
	313
	314	static const struct of_device_id psci_of_match[] __initconst = {
	315	{ .compatible = "arm,psci", .data = psci_0_1_init},
	316	{ .compatible = "arm,psci-0.2", .data = psci_0_2_init},
	317	{},
	318	};
	319
	320	int __init psci_init(void)
	321	{
	322	struct device_node *np;
	323	const struct of_device_id *matched_np;
	324	psci_initcall_t init_fn;
	325
	326	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
	327	if (!np)
	328	return -ENODEV;
	329
	330	init_fn = (psci_initcall_t)matched_np->data;
	331	return init_fn(np);
2bdd424f	332	}