[deliverable/linux.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/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 <uapi/linux/psci.h>

#include <asm/cputype.h>
#include <asm/system_misc.h>
#include <asm/smp_plat.h>

/*
 * 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;

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 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 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 = -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_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
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
	16	#include <linux/errno.h>
	17	#include <linux/linkage.h>
	18	#include <linux/of.h>
	19	#include <linux/pm.h>
	20	#include <linux/printk.h>
	21	#include <linux/psci.h>
	22	#include <linux/reboot.h>
	23
	24	#include <uapi/linux/psci.h>
	25
	26	#include <asm/cputype.h>
	27	#include <asm/system_misc.h>
	28	#include <asm/smp_plat.h>
	29
	30	/*
	31	* The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
	32	* calls to its resident CPU, so we must avoid issuing those. We never migrate
	33	* a Trusted OS even if it claims to be capable of migration -- doing so will
	34	* require cooperation with a Trusted OS driver.
	35	*/
	36	static int resident_cpu = -1;
	37
	38	bool psci_tos_resident_on(int cpu)
	39	{
	40	return cpu == resident_cpu;
	41	}
	42
	43	struct psci_operations psci_ops;
	44
	45	typedef unsigned long (psci_fn)(unsigned long, unsigned long,
	46	unsigned long, unsigned long);
	47	asmlinkage psci_fn __invoke_psci_fn_hvc;
	48	asmlinkage psci_fn __invoke_psci_fn_smc;
	49	static psci_fn *invoke_psci_fn;
	50
	51	enum psci_function {
	52	PSCI_FN_CPU_SUSPEND,
	53	PSCI_FN_CPU_ON,
	54	PSCI_FN_CPU_OFF,
	55	PSCI_FN_MIGRATE,
	56	PSCI_FN_MAX,
	57	};
	58
	59	static u32 psci_function_id[PSCI_FN_MAX];
	60
	61	static int psci_to_linux_errno(int errno)
	62	{
	63	switch (errno) {
	64	case PSCI_RET_SUCCESS:
65	return 0;
66	case PSCI_RET_NOT_SUPPORTED:
67	return -EOPNOTSUPP;
68	case PSCI_RET_INVALID_PARAMS:
69	return -EINVAL;
70	case PSCI_RET_DENIED:
71	return -EPERM;
72	};
73
74	return -EINVAL;
75	}
76
77	static u32 psci_get_version(void)
78	{
79	return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
80	}
81
82	static int psci_cpu_suspend(u32 state, unsigned long entry_point)
83	{
84	int err;
85	u32 fn;
86
87	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
88	err = invoke_psci_fn(fn, state, entry_point, 0);
89	return psci_to_linux_errno(err);
90	}
91
92	static int psci_cpu_off(u32 state)
93	{
94	int err;
95	u32 fn;
96
97	fn = psci_function_id[PSCI_FN_CPU_OFF];
98	err = invoke_psci_fn(fn, state, 0, 0);
99	return psci_to_linux_errno(err);
100	}
101
102	static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
103	{
104	int err;
105	u32 fn;
106
107	fn = psci_function_id[PSCI_FN_CPU_ON];
108	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
109	return psci_to_linux_errno(err);
110	}
111
112	static int psci_migrate(unsigned long cpuid)
113	{
114	int err;
115	u32 fn;
116
117	fn = psci_function_id[PSCI_FN_MIGRATE];
118	err = invoke_psci_fn(fn, cpuid, 0, 0);
119	return psci_to_linux_errno(err);
120	}
121
122	static int psci_affinity_info(unsigned long target_affinity,
123	unsigned long lowest_affinity_level)
124	{
125	return invoke_psci_fn(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity,
126	lowest_affinity_level, 0);
127	}
128
129	static int psci_migrate_info_type(void)
130	{
131	return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
132	}
133
134	static unsigned long psci_migrate_info_up_cpu(void)
135	{
136	return invoke_psci_fn(PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU, 0, 0, 0);
137	}
138
139	static int get_set_conduit_method(struct device_node *np)
140	{
141	const char *method;
142
143	pr_info("probing for conduit method from DT.\n");
144
145	if (of_property_read_string(np, "method", &method)) {
146	pr_warn("missing \"method\" property\n");
147	return -ENXIO;
148	}
149
150	if (!strcmp("hvc", method)) {
151	invoke_psci_fn = __invoke_psci_fn_hvc;
152	} else if (!strcmp("smc", method)) {
153	invoke_psci_fn = __invoke_psci_fn_smc;
154	} else {
155	pr_warn("invalid \"method\" property: %s\n", method);
156	return -EINVAL;
157	}
158	return 0;
159	}
160
161	static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
162	{
163	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
164	}
165
166	static void psci_sys_poweroff(void)
167	{
168	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
169	}
170
171	/*
172	* Detect the presence of a resident Trusted OS which may cause CPU_OFF to
173	* return DENIED (which would be fatal).
174	*/
175	static void __init psci_init_migrate(void)
176	{
177	unsigned long cpuid;
178	int type, cpu = -1;
179
180	type = psci_ops.migrate_info_type();
181
182	if (type == PSCI_0_2_TOS_MP) {
183	pr_info("Trusted OS migration not required\n");
184	return;
185	}
186
187	if (type == PSCI_RET_NOT_SUPPORTED) {
188	pr_info("MIGRATE_INFO_TYPE not supported.\n");
189	return;
190	}
191
192	if (type != PSCI_0_2_TOS_UP_MIGRATE &&
193	type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
194	pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
195	return;
196	}
197
198	cpuid = psci_migrate_info_up_cpu();
199	if (cpuid & ~MPIDR_HWID_BITMASK) {
200	pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
201	cpuid);
202	return;
203	}
204
205	cpu = get_logical_index(cpuid);
206	resident_cpu = cpu >= 0 ? cpu : -1;
207
208	pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
209	}
210
211	static void __init psci_0_2_set_functions(void)
212	{
213	pr_info("Using standard PSCI v0.2 function IDs\n");
214	psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_CPU_SUSPEND;
215	psci_ops.cpu_suspend = psci_cpu_suspend;
216
217	psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
218	psci_ops.cpu_off = psci_cpu_off;
219
220	psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN64_CPU_ON;
221	psci_ops.cpu_on = psci_cpu_on;
222
223	psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN64_MIGRATE;
224	psci_ops.migrate = psci_migrate;
225
226	psci_ops.affinity_info = psci_affinity_info;
227
228	psci_ops.migrate_info_type = psci_migrate_info_type;
229
230	arm_pm_restart = psci_sys_reset;
231
232	pm_power_off = psci_sys_poweroff;
233	}
234
235	/*
236	* Probe function for PSCI firmware versions >= 0.2
237	*/
238	static int __init psci_probe(void)
239	{
240	u32 ver = psci_get_version();
241
242	pr_info("PSCIv%d.%d detected in firmware.\n",
243	PSCI_VERSION_MAJOR(ver),
244	PSCI_VERSION_MINOR(ver));
245
246	if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
247	pr_err("Conflicting PSCI version detected.\n");
248	return -EINVAL;
249	}
250
251	psci_0_2_set_functions();
252
253	psci_init_migrate();
254
255	return 0;
256	}
257
258	typedef int (psci_initcall_t)(const struct device_node );
259
260	/*
261	* PSCI init function for PSCI versions >=0.2
262	*
263	* Probe based on PSCI PSCI_VERSION function
264	*/
265	static int __init psci_0_2_init(struct device_node *np)
266	{
267	int err;
268
269	err = get_set_conduit_method(np);
270
271	if (err)
272	goto out_put_node;
273	/*
274	* Starting with v0.2, the PSCI specification introduced a call
275	* (PSCI_VERSION) that allows probing the firmware version, so
276	* that PSCI function IDs and version specific initialization
277	* can be carried out according to the specific version reported
278	* by firmware
279	*/
280	err = psci_probe();
281
282	out_put_node:
283	of_node_put(np);
284	return err;
285	}
286
287	/*
288	* PSCI < v0.2 get PSCI Function IDs via DT.
289	*/
290	static int __init psci_0_1_init(struct device_node *np)
291	{
292	u32 id;
293	int err;
294
295	err = get_set_conduit_method(np);
296
297	if (err)
298	goto out_put_node;
299
300	pr_info("Using PSCI v0.1 Function IDs from DT\n");
301
302	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
303	psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
304	psci_ops.cpu_suspend = psci_cpu_suspend;
305	}
306
307	if (!of_property_read_u32(np, "cpu_off", &id)) {
308	psci_function_id[PSCI_FN_CPU_OFF] = id;
309	psci_ops.cpu_off = psci_cpu_off;
310	}
311
312	if (!of_property_read_u32(np, "cpu_on", &id)) {
313	psci_function_id[PSCI_FN_CPU_ON] = id;
314	psci_ops.cpu_on = psci_cpu_on;
315	}
316
317	if (!of_property_read_u32(np, "migrate", &id)) {
318	psci_function_id[PSCI_FN_MIGRATE] = id;
319	psci_ops.migrate = psci_migrate;
320	}
321
322	out_put_node:
323	of_node_put(np);
324	return err;
325	}
326
327	static const struct of_device_id psci_of_match[] __initconst = {
328	{ .compatible = "arm,psci", .data = psci_0_1_init},
329	{ .compatible = "arm,psci-0.2", .data = psci_0_2_init},
330	{},
331	};
332
333	int __init psci_dt_init(void)
334	{
335	struct device_node *np;
336	const struct of_device_id *matched_np;
337	psci_initcall_t init_fn;
338
339	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
340
341	if (!np)
342	return -ENODEV;
343
344	init_fn = (psci_initcall_t)matched_np->data;
345	return init_fn(np);
346	}
347
348	#ifdef CONFIG_ACPI
349	/*
350	* We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
351	* explicitly clarified in SBBR
352	*/
353	int __init psci_acpi_init(void)
354	{
355	if (!acpi_psci_present()) {
356	pr_info("is not implemented in ACPI.\n");
357	return -EOPNOTSUPP;
358	}
359
360	pr_info("probing for conduit method from ACPI.\n");
361
362	if (acpi_psci_use_hvc())
363	invoke_psci_fn = __invoke_psci_fn_hvc;
364	else
365	invoke_psci_fn = __invoke_psci_fn_smc;
366
367	return psci_probe();
368	}
369	#endif