1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 *
4 * Copyright (C) 2015 ARM Limited
5 */
6
7 #define pr_fmt(fmt) "psci: " fmt
8
9 #include <linux/acpi.h>
10 #include <linux/arm-smccc.h>
11 #include <linux/cpuidle.h>
12 #include <linux/debugfs.h>
13 #include <linux/errno.h>
14 #include <linux/linkage.h>
15 #include <linux/of.h>
16 #include <linux/pm.h>
17 #include <linux/printk.h>
18 #include <linux/psci.h>
19 #include <linux/reboot.h>
20 #include <linux/slab.h>
21 #include <linux/suspend.h>
22
23 #include <uapi/linux/psci.h>
24
25 #include <asm/cpuidle.h>
26 #include <asm/cputype.h>
27 #include <asm/hypervisor.h>
28 #include <asm/system_misc.h>
29 #include <asm/smp_plat.h>
30 #include <asm/suspend.h>
31
32 /*
33 * While a 64-bit OS can make calls with SMC32 calling conventions, for some
34 * calls it is necessary to use SMC64 to pass or return 64-bit values.
35 * For such calls PSCI_FN_NATIVE(version, name) will choose the appropriate
36 * (native-width) function ID.
37 */
38 #ifdef CONFIG_64BIT
39 #define PSCI_FN_NATIVE(version, name) PSCI_##version##_FN64_##name
40 #else
41 #define PSCI_FN_NATIVE(version, name) PSCI_##version##_FN_##name
42 #endif
43
44 /*
45 * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
46 * calls to its resident CPU, so we must avoid issuing those. We never migrate
47 * a Trusted OS even if it claims to be capable of migration -- doing so will
48 * require cooperation with a Trusted OS driver.
49 */
50 static int resident_cpu = -1;
51 struct psci_operations psci_ops;
52 static enum arm_smccc_conduit psci_conduit = SMCCC_CONDUIT_NONE;
53
psci_tos_resident_on(int cpu)54 bool psci_tos_resident_on(int cpu)
55 {
56 return cpu == resident_cpu;
57 }
58
59 typedef unsigned long (psci_fn)(unsigned long, unsigned long,
60 unsigned long, unsigned long);
61 static psci_fn *invoke_psci_fn;
62
63 static struct psci_0_1_function_ids psci_0_1_function_ids;
64
get_psci_0_1_function_ids(void)65 struct psci_0_1_function_ids get_psci_0_1_function_ids(void)
66 {
67 return psci_0_1_function_ids;
68 }
69
70 #define PSCI_0_2_POWER_STATE_MASK \
71 (PSCI_0_2_POWER_STATE_ID_MASK | \
72 PSCI_0_2_POWER_STATE_TYPE_MASK | \
73 PSCI_0_2_POWER_STATE_AFFL_MASK)
74
75 #define PSCI_1_0_EXT_POWER_STATE_MASK \
76 (PSCI_1_0_EXT_POWER_STATE_ID_MASK | \
77 PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)
78
79 static u32 psci_cpu_suspend_feature;
80 static bool psci_system_reset2_supported;
81
psci_has_ext_power_state(void)82 static inline bool psci_has_ext_power_state(void)
83 {
84 return psci_cpu_suspend_feature &
85 PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
86 }
87
psci_has_osi_support(void)88 bool psci_has_osi_support(void)
89 {
90 return psci_cpu_suspend_feature & PSCI_1_0_OS_INITIATED;
91 }
92
psci_power_state_loses_context(u32 state)93 static inline bool psci_power_state_loses_context(u32 state)
94 {
95 const u32 mask = psci_has_ext_power_state() ?
96 PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :
97 PSCI_0_2_POWER_STATE_TYPE_MASK;
98
99 return state & mask;
100 }
101
psci_power_state_is_valid(u32 state)102 bool psci_power_state_is_valid(u32 state)
103 {
104 const u32 valid_mask = psci_has_ext_power_state() ?
105 PSCI_1_0_EXT_POWER_STATE_MASK :
106 PSCI_0_2_POWER_STATE_MASK;
107
108 return !(state & ~valid_mask);
109 }
110
__invoke_psci_fn_hvc(unsigned long function_id,unsigned long arg0,unsigned long arg1,unsigned long arg2)111 static unsigned long __invoke_psci_fn_hvc(unsigned long function_id,
112 unsigned long arg0, unsigned long arg1,
113 unsigned long arg2)
114 {
115 struct arm_smccc_res res;
116
117 arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
118 return res.a0;
119 }
120
__invoke_psci_fn_smc(unsigned long function_id,unsigned long arg0,unsigned long arg1,unsigned long arg2)121 static unsigned long __invoke_psci_fn_smc(unsigned long function_id,
122 unsigned long arg0, unsigned long arg1,
123 unsigned long arg2)
124 {
125 struct arm_smccc_res res;
126
127 arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
128 return res.a0;
129 }
130
psci_to_linux_errno(int errno)131 static int psci_to_linux_errno(int errno)
132 {
133 switch (errno) {
134 case PSCI_RET_SUCCESS:
135 return 0;
136 case PSCI_RET_NOT_SUPPORTED:
137 return -EOPNOTSUPP;
138 case PSCI_RET_INVALID_PARAMS:
139 case PSCI_RET_INVALID_ADDRESS:
140 return -EINVAL;
141 case PSCI_RET_DENIED:
142 return -EPERM;
143 }
144
145 return -EINVAL;
146 }
147
psci_0_1_get_version(void)148 static u32 psci_0_1_get_version(void)
149 {
150 return PSCI_VERSION(0, 1);
151 }
152
psci_0_2_get_version(void)153 static u32 psci_0_2_get_version(void)
154 {
155 return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
156 }
157
psci_set_osi_mode(bool enable)158 int psci_set_osi_mode(bool enable)
159 {
160 unsigned long suspend_mode;
161 int err;
162
163 suspend_mode = enable ? PSCI_1_0_SUSPEND_MODE_OSI :
164 PSCI_1_0_SUSPEND_MODE_PC;
165
166 err = invoke_psci_fn(PSCI_1_0_FN_SET_SUSPEND_MODE, suspend_mode, 0, 0);
167 if (err < 0)
168 pr_warn("failed to set %s mode: %d\n", enable ? "OSI" : "PC", err);
169 return psci_to_linux_errno(err);
170 }
171
__psci_cpu_suspend(u32 fn,u32 state,unsigned long entry_point)172 static int __psci_cpu_suspend(u32 fn, u32 state, unsigned long entry_point)
173 {
174 int err;
175
176 err = invoke_psci_fn(fn, state, entry_point, 0);
177 return psci_to_linux_errno(err);
178 }
179
psci_0_1_cpu_suspend(u32 state,unsigned long entry_point)180 static int psci_0_1_cpu_suspend(u32 state, unsigned long entry_point)
181 {
182 return __psci_cpu_suspend(psci_0_1_function_ids.cpu_suspend,
183 state, entry_point);
184 }
185
psci_0_2_cpu_suspend(u32 state,unsigned long entry_point)186 static int psci_0_2_cpu_suspend(u32 state, unsigned long entry_point)
187 {
188 return __psci_cpu_suspend(PSCI_FN_NATIVE(0_2, CPU_SUSPEND),
189 state, entry_point);
190 }
191
__psci_cpu_off(u32 fn,u32 state)192 static int __psci_cpu_off(u32 fn, u32 state)
193 {
194 int err;
195
196 err = invoke_psci_fn(fn, state, 0, 0);
197 return psci_to_linux_errno(err);
198 }
199
psci_0_1_cpu_off(u32 state)200 static int psci_0_1_cpu_off(u32 state)
201 {
202 return __psci_cpu_off(psci_0_1_function_ids.cpu_off, state);
203 }
204
psci_0_2_cpu_off(u32 state)205 static int psci_0_2_cpu_off(u32 state)
206 {
207 return __psci_cpu_off(PSCI_0_2_FN_CPU_OFF, state);
208 }
209
__psci_cpu_on(u32 fn,unsigned long cpuid,unsigned long entry_point)210 static int __psci_cpu_on(u32 fn, unsigned long cpuid, unsigned long entry_point)
211 {
212 int err;
213
214 err = invoke_psci_fn(fn, cpuid, entry_point, 0);
215 return psci_to_linux_errno(err);
216 }
217
psci_0_1_cpu_on(unsigned long cpuid,unsigned long entry_point)218 static int psci_0_1_cpu_on(unsigned long cpuid, unsigned long entry_point)
219 {
220 return __psci_cpu_on(psci_0_1_function_ids.cpu_on, cpuid, entry_point);
221 }
222
psci_0_2_cpu_on(unsigned long cpuid,unsigned long entry_point)223 static int psci_0_2_cpu_on(unsigned long cpuid, unsigned long entry_point)
224 {
225 return __psci_cpu_on(PSCI_FN_NATIVE(0_2, CPU_ON), cpuid, entry_point);
226 }
227
__psci_migrate(u32 fn,unsigned long cpuid)228 static int __psci_migrate(u32 fn, unsigned long cpuid)
229 {
230 int err;
231
232 err = invoke_psci_fn(fn, cpuid, 0, 0);
233 return psci_to_linux_errno(err);
234 }
235
psci_0_1_migrate(unsigned long cpuid)236 static int psci_0_1_migrate(unsigned long cpuid)
237 {
238 return __psci_migrate(psci_0_1_function_ids.migrate, cpuid);
239 }
240
psci_0_2_migrate(unsigned long cpuid)241 static int psci_0_2_migrate(unsigned long cpuid)
242 {
243 return __psci_migrate(PSCI_FN_NATIVE(0_2, MIGRATE), cpuid);
244 }
245
psci_affinity_info(unsigned long target_affinity,unsigned long lowest_affinity_level)246 static int psci_affinity_info(unsigned long target_affinity,
247 unsigned long lowest_affinity_level)
248 {
249 return invoke_psci_fn(PSCI_FN_NATIVE(0_2, AFFINITY_INFO),
250 target_affinity, lowest_affinity_level, 0);
251 }
252
psci_migrate_info_type(void)253 static int psci_migrate_info_type(void)
254 {
255 return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
256 }
257
psci_migrate_info_up_cpu(void)258 static unsigned long psci_migrate_info_up_cpu(void)
259 {
260 return invoke_psci_fn(PSCI_FN_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
261 0, 0, 0);
262 }
263
set_conduit(enum arm_smccc_conduit conduit)264 static void set_conduit(enum arm_smccc_conduit conduit)
265 {
266 switch (conduit) {
267 case SMCCC_CONDUIT_HVC:
268 invoke_psci_fn = __invoke_psci_fn_hvc;
269 break;
270 case SMCCC_CONDUIT_SMC:
271 invoke_psci_fn = __invoke_psci_fn_smc;
272 break;
273 default:
274 WARN(1, "Unexpected PSCI conduit %d\n", conduit);
275 }
276
277 psci_conduit = conduit;
278 }
279
get_set_conduit_method(const struct device_node * np)280 static int get_set_conduit_method(const struct device_node *np)
281 {
282 const char *method;
283
284 pr_info("probing for conduit method from DT.\n");
285
286 if (of_property_read_string(np, "method", &method)) {
287 pr_warn("missing \"method\" property\n");
288 return -ENXIO;
289 }
290
291 if (!strcmp("hvc", method)) {
292 set_conduit(SMCCC_CONDUIT_HVC);
293 } else if (!strcmp("smc", method)) {
294 set_conduit(SMCCC_CONDUIT_SMC);
295 } else {
296 pr_warn("invalid \"method\" property: %s\n", method);
297 return -EINVAL;
298 }
299 return 0;
300 }
301
psci_sys_reset(struct notifier_block * nb,unsigned long action,void * data)302 static int psci_sys_reset(struct notifier_block *nb, unsigned long action,
303 void *data)
304 {
305 if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&
306 psci_system_reset2_supported) {
307 /*
308 * reset_type[31] = 0 (architectural)
309 * reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
310 * cookie = 0 (ignored by the implementation)
311 */
312 invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);
313 } else {
314 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
315 }
316
317 return NOTIFY_DONE;
318 }
319
320 static struct notifier_block psci_sys_reset_nb = {
321 .notifier_call = psci_sys_reset,
322 .priority = 129,
323 };
324
psci_sys_poweroff(void)325 static void psci_sys_poweroff(void)
326 {
327 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
328 }
329
psci_features(u32 psci_func_id)330 static int psci_features(u32 psci_func_id)
331 {
332 return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
333 psci_func_id, 0, 0);
334 }
335
336 #ifdef CONFIG_DEBUG_FS
337
338 #define PSCI_ID(ver, _name) \
339 { .fn = PSCI_##ver##_FN_##_name, .name = #_name, }
340 #define PSCI_ID_NATIVE(ver, _name) \
341 { .fn = PSCI_FN_NATIVE(ver, _name), .name = #_name, }
342
343 /* A table of all optional functions */
344 static const struct {
345 u32 fn;
346 const char *name;
347 } psci_fn_ids[] = {
348 PSCI_ID_NATIVE(0_2, MIGRATE),
349 PSCI_ID(0_2, MIGRATE_INFO_TYPE),
350 PSCI_ID_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
351 PSCI_ID(1_0, CPU_FREEZE),
352 PSCI_ID_NATIVE(1_0, CPU_DEFAULT_SUSPEND),
353 PSCI_ID_NATIVE(1_0, NODE_HW_STATE),
354 PSCI_ID_NATIVE(1_0, SYSTEM_SUSPEND),
355 PSCI_ID(1_0, SET_SUSPEND_MODE),
356 PSCI_ID_NATIVE(1_0, STAT_RESIDENCY),
357 PSCI_ID_NATIVE(1_0, STAT_COUNT),
358 PSCI_ID_NATIVE(1_1, SYSTEM_RESET2),
359 PSCI_ID(1_1, MEM_PROTECT),
360 PSCI_ID_NATIVE(1_1, MEM_PROTECT_CHECK_RANGE),
361 };
362
psci_debugfs_read(struct seq_file * s,void * data)363 static int psci_debugfs_read(struct seq_file *s, void *data)
364 {
365 int feature, type, i;
366 u32 ver;
367
368 ver = psci_ops.get_version();
369 seq_printf(s, "PSCIv%d.%d\n",
370 PSCI_VERSION_MAJOR(ver),
371 PSCI_VERSION_MINOR(ver));
372
373 /* PSCI_FEATURES is available only starting from 1.0 */
374 if (PSCI_VERSION_MAJOR(ver) < 1)
375 return 0;
376
377 feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
378 if (feature != PSCI_RET_NOT_SUPPORTED) {
379 ver = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
380 seq_printf(s, "SMC Calling Convention v%d.%d\n",
381 PSCI_VERSION_MAJOR(ver),
382 PSCI_VERSION_MINOR(ver));
383 } else {
384 seq_puts(s, "SMC Calling Convention v1.0 is assumed\n");
385 }
386
387 feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND));
388 if (feature < 0) {
389 seq_printf(s, "PSCI_FEATURES(CPU_SUSPEND) error (%d)\n", feature);
390 } else {
391 seq_printf(s, "OSI is %ssupported\n",
392 (feature & BIT(0)) ? "" : "not ");
393 seq_printf(s, "%s StateID format is used\n",
394 (feature & BIT(1)) ? "Extended" : "Original");
395 }
396
397 type = psci_ops.migrate_info_type();
398 if (type == PSCI_0_2_TOS_UP_MIGRATE ||
399 type == PSCI_0_2_TOS_UP_NO_MIGRATE) {
400 unsigned long cpuid;
401
402 seq_printf(s, "Trusted OS %smigrate capable\n",
403 type == PSCI_0_2_TOS_UP_NO_MIGRATE ? "not " : "");
404 cpuid = psci_migrate_info_up_cpu();
405 seq_printf(s, "Trusted OS resident on physical CPU 0x%lx (#%d)\n",
406 cpuid, resident_cpu);
407 } else if (type == PSCI_0_2_TOS_MP) {
408 seq_puts(s, "Trusted OS migration not required\n");
409 } else {
410 if (type != PSCI_RET_NOT_SUPPORTED)
411 seq_printf(s, "MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
412 }
413
414 for (i = 0; i < ARRAY_SIZE(psci_fn_ids); i++) {
415 feature = psci_features(psci_fn_ids[i].fn);
416 if (feature == PSCI_RET_NOT_SUPPORTED)
417 continue;
418 if (feature < 0)
419 seq_printf(s, "PSCI_FEATURES(%s) error (%d)\n",
420 psci_fn_ids[i].name, feature);
421 else
422 seq_printf(s, "%s is supported\n", psci_fn_ids[i].name);
423 }
424
425 return 0;
426 }
427
psci_debugfs_open(struct inode * inode,struct file * f)428 static int psci_debugfs_open(struct inode *inode, struct file *f)
429 {
430 return single_open(f, psci_debugfs_read, NULL);
431 }
432
433 static const struct file_operations psci_debugfs_ops = {
434 .owner = THIS_MODULE,
435 .open = psci_debugfs_open,
436 .release = single_release,
437 .read = seq_read,
438 .llseek = seq_lseek
439 };
440
psci_debugfs_init(void)441 static int __init psci_debugfs_init(void)
442 {
443 return PTR_ERR_OR_ZERO(debugfs_create_file("psci", 0444, NULL, NULL,
444 &psci_debugfs_ops));
445 }
late_initcall(psci_debugfs_init)446 late_initcall(psci_debugfs_init)
447 #endif
448
449 #ifdef CONFIG_CPU_IDLE
450 static int psci_suspend_finisher(unsigned long state)
451 {
452 u32 power_state = state;
453 phys_addr_t pa_cpu_resume = __pa_symbol(cpu_resume);
454
455 return psci_ops.cpu_suspend(power_state, pa_cpu_resume);
456 }
457
psci_cpu_suspend_enter(u32 state)458 int psci_cpu_suspend_enter(u32 state)
459 {
460 int ret;
461
462 if (!psci_power_state_loses_context(state)) {
463 struct arm_cpuidle_irq_context context;
464
465 arm_cpuidle_save_irq_context(&context);
466 ret = psci_ops.cpu_suspend(state, 0);
467 arm_cpuidle_restore_irq_context(&context);
468 } else {
469 ret = cpu_suspend(state, psci_suspend_finisher);
470 }
471
472 return ret;
473 }
474 #endif
475
psci_system_suspend(unsigned long unused)476 static int psci_system_suspend(unsigned long unused)
477 {
478 phys_addr_t pa_cpu_resume = __pa_symbol(cpu_resume);
479
480 return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
481 pa_cpu_resume, 0, 0);
482 }
483
psci_system_suspend_enter(suspend_state_t state)484 static int psci_system_suspend_enter(suspend_state_t state)
485 {
486 return cpu_suspend(0, psci_system_suspend);
487 }
488
489 static const struct platform_suspend_ops psci_suspend_ops = {
490 .valid = suspend_valid_only_mem,
491 .enter = psci_system_suspend_enter,
492 };
493
psci_init_system_reset2(void)494 static void __init psci_init_system_reset2(void)
495 {
496 int ret;
497
498 ret = psci_features(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2));
499
500 if (ret != PSCI_RET_NOT_SUPPORTED)
501 psci_system_reset2_supported = true;
502 }
503
psci_init_system_suspend(void)504 static void __init psci_init_system_suspend(void)
505 {
506 int ret;
507
508 if (!IS_ENABLED(CONFIG_SUSPEND))
509 return;
510
511 ret = psci_features(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND));
512
513 if (ret != PSCI_RET_NOT_SUPPORTED)
514 suspend_set_ops(&psci_suspend_ops);
515 }
516
psci_init_cpu_suspend(void)517 static void __init psci_init_cpu_suspend(void)
518 {
519 int feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND));
520
521 if (feature != PSCI_RET_NOT_SUPPORTED)
522 psci_cpu_suspend_feature = feature;
523 }
524
525 /*
526 * Detect the presence of a resident Trusted OS which may cause CPU_OFF to
527 * return DENIED (which would be fatal).
528 */
psci_init_migrate(void)529 static void __init psci_init_migrate(void)
530 {
531 unsigned long cpuid;
532 int type, cpu = -1;
533
534 type = psci_ops.migrate_info_type();
535
536 if (type == PSCI_0_2_TOS_MP) {
537 pr_info("Trusted OS migration not required\n");
538 return;
539 }
540
541 if (type == PSCI_RET_NOT_SUPPORTED) {
542 pr_info("MIGRATE_INFO_TYPE not supported.\n");
543 return;
544 }
545
546 if (type != PSCI_0_2_TOS_UP_MIGRATE &&
547 type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
548 pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
549 return;
550 }
551
552 cpuid = psci_migrate_info_up_cpu();
553 if (cpuid & ~MPIDR_HWID_BITMASK) {
554 pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
555 cpuid);
556 return;
557 }
558
559 cpu = get_logical_index(cpuid);
560 resident_cpu = cpu >= 0 ? cpu : -1;
561
562 pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
563 }
564
psci_init_smccc(void)565 static void __init psci_init_smccc(void)
566 {
567 u32 ver = ARM_SMCCC_VERSION_1_0;
568 int feature;
569
570 feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
571
572 if (feature != PSCI_RET_NOT_SUPPORTED) {
573 u32 ret;
574 ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
575 if (ret >= ARM_SMCCC_VERSION_1_1) {
576 arm_smccc_version_init(ret, psci_conduit);
577 ver = ret;
578 }
579 }
580
581 /*
582 * Conveniently, the SMCCC and PSCI versions are encoded the
583 * same way. No, this isn't accidental.
584 */
585 pr_info("SMC Calling Convention v%d.%d\n",
586 PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver));
587
588 }
589
psci_0_2_set_functions(void)590 static void __init psci_0_2_set_functions(void)
591 {
592 pr_info("Using standard PSCI v0.2 function IDs\n");
593
594 psci_ops = (struct psci_operations){
595 .get_version = psci_0_2_get_version,
596 .cpu_suspend = psci_0_2_cpu_suspend,
597 .cpu_off = psci_0_2_cpu_off,
598 .cpu_on = psci_0_2_cpu_on,
599 .migrate = psci_0_2_migrate,
600 .affinity_info = psci_affinity_info,
601 .migrate_info_type = psci_migrate_info_type,
602 };
603
604 register_restart_handler(&psci_sys_reset_nb);
605
606 pm_power_off = psci_sys_poweroff;
607 }
608
609 /*
610 * Probe function for PSCI firmware versions >= 0.2
611 */
psci_probe(void)612 static int __init psci_probe(void)
613 {
614 u32 ver = psci_0_2_get_version();
615
616 pr_info("PSCIv%d.%d detected in firmware.\n",
617 PSCI_VERSION_MAJOR(ver),
618 PSCI_VERSION_MINOR(ver));
619
620 if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
621 pr_err("Conflicting PSCI version detected.\n");
622 return -EINVAL;
623 }
624
625 psci_0_2_set_functions();
626
627 psci_init_migrate();
628
629 if (PSCI_VERSION_MAJOR(ver) >= 1) {
630 psci_init_smccc();
631 psci_init_cpu_suspend();
632 psci_init_system_suspend();
633 psci_init_system_reset2();
634 kvm_init_hyp_services();
635 }
636
637 return 0;
638 }
639
640 typedef int (*psci_initcall_t)(const struct device_node *);
641
642 /*
643 * PSCI init function for PSCI versions >=0.2
644 *
645 * Probe based on PSCI PSCI_VERSION function
646 */
psci_0_2_init(const struct device_node * np)647 static int __init psci_0_2_init(const struct device_node *np)
648 {
649 int err;
650
651 err = get_set_conduit_method(np);
652 if (err)
653 return err;
654
655 /*
656 * Starting with v0.2, the PSCI specification introduced a call
657 * (PSCI_VERSION) that allows probing the firmware version, so
658 * that PSCI function IDs and version specific initialization
659 * can be carried out according to the specific version reported
660 * by firmware
661 */
662 return psci_probe();
663 }
664
665 /*
666 * PSCI < v0.2 get PSCI Function IDs via DT.
667 */
psci_0_1_init(const struct device_node * np)668 static int __init psci_0_1_init(const struct device_node *np)
669 {
670 u32 id;
671 int err;
672
673 err = get_set_conduit_method(np);
674 if (err)
675 return err;
676
677 pr_info("Using PSCI v0.1 Function IDs from DT\n");
678
679 psci_ops.get_version = psci_0_1_get_version;
680
681 if (!of_property_read_u32(np, "cpu_suspend", &id)) {
682 psci_0_1_function_ids.cpu_suspend = id;
683 psci_ops.cpu_suspend = psci_0_1_cpu_suspend;
684 }
685
686 if (!of_property_read_u32(np, "cpu_off", &id)) {
687 psci_0_1_function_ids.cpu_off = id;
688 psci_ops.cpu_off = psci_0_1_cpu_off;
689 }
690
691 if (!of_property_read_u32(np, "cpu_on", &id)) {
692 psci_0_1_function_ids.cpu_on = id;
693 psci_ops.cpu_on = psci_0_1_cpu_on;
694 }
695
696 if (!of_property_read_u32(np, "migrate", &id)) {
697 psci_0_1_function_ids.migrate = id;
698 psci_ops.migrate = psci_0_1_migrate;
699 }
700
701 return 0;
702 }
703
psci_1_0_init(const struct device_node * np)704 static int __init psci_1_0_init(const struct device_node *np)
705 {
706 int err;
707
708 err = psci_0_2_init(np);
709 if (err)
710 return err;
711
712 if (psci_has_osi_support()) {
713 pr_info("OSI mode supported.\n");
714
715 /* Default to PC mode. */
716 psci_set_osi_mode(false);
717 }
718
719 return 0;
720 }
721
722 static const struct of_device_id psci_of_match[] __initconst = {
723 { .compatible = "arm,psci", .data = psci_0_1_init},
724 { .compatible = "arm,psci-0.2", .data = psci_0_2_init},
725 { .compatible = "arm,psci-1.0", .data = psci_1_0_init},
726 {},
727 };
728
psci_dt_init(void)729 int __init psci_dt_init(void)
730 {
731 struct device_node *np;
732 const struct of_device_id *matched_np;
733 psci_initcall_t init_fn;
734 int ret;
735
736 np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
737
738 if (!np || !of_device_is_available(np))
739 return -ENODEV;
740
741 init_fn = (psci_initcall_t)matched_np->data;
742 ret = init_fn(np);
743
744 of_node_put(np);
745 return ret;
746 }
747
748 #ifdef CONFIG_ACPI
749 /*
750 * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
751 * explicitly clarified in SBBR
752 */
psci_acpi_init(void)753 int __init psci_acpi_init(void)
754 {
755 if (!acpi_psci_present()) {
756 pr_info("is not implemented in ACPI.\n");
757 return -EOPNOTSUPP;
758 }
759
760 pr_info("probing for conduit method from ACPI.\n");
761
762 if (acpi_psci_use_hvc())
763 set_conduit(SMCCC_CONDUIT_HVC);
764 else
765 set_conduit(SMCCC_CONDUIT_SMC);
766
767 return psci_probe();
768 }
769 #endif
770
