[GitHub/mt8127/android_kernel_alcatel_ttab.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 <asm/compiler.h>
#include <asm/errno.h>
#include <asm/opcodes-sec.h>
#include <asm/opcodes-virt.h>
#include <asm/psci.h>

struct psci_operations psci_ops;

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

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_RET_SUCCESS		0
#define PSCI_RET_EOPNOTSUPP		-1
#define PSCI_RET_EINVAL			-2
#define PSCI_RET_EPERM			-3

static int psci_to_linux_errno(int errno)
{
	switch (errno) {
	case PSCI_RET_SUCCESS:
		return 0;
	case PSCI_RET_EOPNOTSUPP:
		return -EOPNOTSUPP;
	case PSCI_RET_EINVAL:
		return -EINVAL;
	case PSCI_RET_EPERM:
		return -EPERM;
	};

	return -EINVAL;
}

#define PSCI_POWER_STATE_ID_MASK	0xffff
#define PSCI_POWER_STATE_ID_SHIFT	0
#define PSCI_POWER_STATE_TYPE_MASK	0x1
#define PSCI_POWER_STATE_TYPE_SHIFT	16
#define PSCI_POWER_STATE_AFFL_MASK	0x3
#define PSCI_POWER_STATE_AFFL_SHIFT	24

static u32 psci_power_state_pack(struct psci_power_state state)
{
	return	((state.id & PSCI_POWER_STATE_ID_MASK)
			<< PSCI_POWER_STATE_ID_SHIFT)	|
		((state.type & PSCI_POWER_STATE_TYPE_MASK)
			<< PSCI_POWER_STATE_TYPE_SHIFT)	|
		((state.affinity_level & PSCI_POWER_STATE_AFFL_MASK)
			<< PSCI_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(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_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 const struct of_device_id psci_of_match[] __initconst = {
	{ .compatible = "arm,psci",	},
	{},
};

static int __init psci_init(void)
{
	struct device_node *np;
	const char *method;
	u32 id;

	np = of_find_matching_node(NULL, psci_of_match);
	if (!np)
		return 0;

	pr_info("probing function IDs from device-tree\n");

	if (of_property_read_string(np, "method", &method)) {
		pr_warning("missing \"method\" property\n");
		goto out_put_node;
	}

	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_warning("invalid \"method\" property: %s\n", method);
		goto out_put_node;
	}

	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 0;
}
early_initcall(psci_init);
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>
	20
	21	#include <asm/compiler.h>
	22	#include <asm/errno.h>
	23	#include <asm/opcodes-sec.h>
	24	#include <asm/opcodes-virt.h>
	25	#include <asm/psci.h>
	26
	27	struct psci_operations psci_ops;
	28
	29	static int (*invoke_psci_fn)(u32, u32, u32, u32);
	30
	31	enum psci_function {
	32	PSCI_FN_CPU_SUSPEND,
	33	PSCI_FN_CPU_ON,
	34	PSCI_FN_CPU_OFF,
	35	PSCI_FN_MIGRATE,
	36	PSCI_FN_MAX,
	37	};
	38
	39	static u32 psci_function_id[PSCI_FN_MAX];
	40
	41	#define PSCI_RET_SUCCESS 0
	42	#define PSCI_RET_EOPNOTSUPP -1
	43	#define PSCI_RET_EINVAL -2
	44	#define PSCI_RET_EPERM -3
	45
	46	static int psci_to_linux_errno(int errno)
	47	{
	48	switch (errno) {
	49	case PSCI_RET_SUCCESS:
	50	return 0;
	51	case PSCI_RET_EOPNOTSUPP:
	52	return -EOPNOTSUPP;
	53	case PSCI_RET_EINVAL:
	54	return -EINVAL;
	55	case PSCI_RET_EPERM:
	56	return -EPERM;
	57	};
	58
	59	return -EINVAL;
	60	}
	61
	62	#define PSCI_POWER_STATE_ID_MASK 0xffff
	63	#define PSCI_POWER_STATE_ID_SHIFT 0
	64	#define PSCI_POWER_STATE_TYPE_MASK 0x1
65	#define PSCI_POWER_STATE_TYPE_SHIFT 16
66	#define PSCI_POWER_STATE_AFFL_MASK 0x3
67	#define PSCI_POWER_STATE_AFFL_SHIFT 24
68
69	static u32 psci_power_state_pack(struct psci_power_state state)
70	{
71	return ((state.id & PSCI_POWER_STATE_ID_MASK)
72	<< PSCI_POWER_STATE_ID_SHIFT) \|
73	((state.type & PSCI_POWER_STATE_TYPE_MASK)
74	<< PSCI_POWER_STATE_TYPE_SHIFT) \|
75	((state.affinity_level & PSCI_POWER_STATE_AFFL_MASK)
76	<< PSCI_POWER_STATE_AFFL_SHIFT);
77	}
78
79	/*
80	* The following two functions are invoked via the invoke_psci_fn pointer
81	* and will not be inlined, allowing us to piggyback on the AAPCS.
82	*/
83	static noinline int __invoke_psci_fn_hvc(u32 function_id, u32 arg0, u32 arg1,
84	u32 arg2)
85	{
86	asm volatile(
87	__asmeq("%0", "r0")
88	__asmeq("%1", "r1")
89	__asmeq("%2", "r2")
90	__asmeq("%3", "r3")
91	__HVC(0)
92	: "+r" (function_id)
93	: "r" (arg0), "r" (arg1), "r" (arg2));
94
95	return function_id;
96	}
97
98	static noinline int __invoke_psci_fn_smc(u32 function_id, u32 arg0, u32 arg1,
99	u32 arg2)
100	{
101	asm volatile(
102	__asmeq("%0", "r0")
103	__asmeq("%1", "r1")
104	__asmeq("%2", "r2")
105	__asmeq("%3", "r3")
106	__SMC(0)
107	: "+r" (function_id)
108	: "r" (arg0), "r" (arg1), "r" (arg2));
109
110	return function_id;
111	}
112
113	static int psci_cpu_suspend(struct psci_power_state state,
114	unsigned long entry_point)
115	{
116	int err;
117	u32 fn, power_state;
118
119	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
120	power_state = psci_power_state_pack(state);
121	err = invoke_psci_fn(fn, power_state, entry_point, 0);
122	return psci_to_linux_errno(err);
123	}
124
125	static int psci_cpu_off(struct psci_power_state state)
126	{
127	int err;
128	u32 fn, power_state;
129
130	fn = psci_function_id[PSCI_FN_CPU_OFF];
131	power_state = psci_power_state_pack(state);
132	err = invoke_psci_fn(fn, power_state, 0, 0);
133	return psci_to_linux_errno(err);
134	}
135
136	static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
137	{
138	int err;
139	u32 fn;
140
141	fn = psci_function_id[PSCI_FN_CPU_ON];
142	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
143	return psci_to_linux_errno(err);
144	}
145
146	static int psci_migrate(unsigned long cpuid)
147	{
148	int err;
149	u32 fn;
150
151	fn = psci_function_id[PSCI_FN_MIGRATE];
152	err = invoke_psci_fn(fn, cpuid, 0, 0);
153	return psci_to_linux_errno(err);
154	}
155
156	static const struct of_device_id psci_of_match[] __initconst = {
157	{ .compatible = "arm,psci", },
158	{},
159	};
160
161	static int __init psci_init(void)
162	{
163	struct device_node *np;
164	const char *method;
165	u32 id;
166
167	np = of_find_matching_node(NULL, psci_of_match);
168	if (!np)
169	return 0;
170
171	pr_info("probing function IDs from device-tree\n");
172
173	if (of_property_read_string(np, "method", &method)) {
174	pr_warning("missing \"method\" property\n");
175	goto out_put_node;
176	}
177
178	if (!strcmp("hvc", method)) {
179	invoke_psci_fn = __invoke_psci_fn_hvc;
180	} else if (!strcmp("smc", method)) {
181	invoke_psci_fn = __invoke_psci_fn_smc;
182	} else {
183	pr_warning("invalid \"method\" property: %s\n", method);
184	goto out_put_node;
185	}
186
187	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
188	psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
189	psci_ops.cpu_suspend = psci_cpu_suspend;
190	}
191
192	if (!of_property_read_u32(np, "cpu_off", &id)) {
193	psci_function_id[PSCI_FN_CPU_OFF] = id;
194	psci_ops.cpu_off = psci_cpu_off;
195	}
196
197	if (!of_property_read_u32(np, "cpu_on", &id)) {
198	psci_function_id[PSCI_FN_CPU_ON] = id;
199	psci_ops.cpu_on = psci_cpu_on;
200	}
201
202	if (!of_property_read_u32(np, "migrate", &id)) {
203	psci_function_id[PSCI_FN_MIGRATE] = id;
204	psci_ops.migrate = psci_migrate;
205	}
206
207	out_put_node:
208	of_node_put(np);
209	return 0;
210	}
211	early_initcall(psci_init);