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v6.8
  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 */
 50static int resident_cpu = -1;
 51struct psci_operations psci_ops;
 52static enum arm_smccc_conduit psci_conduit = SMCCC_CONDUIT_NONE;
 53
 54bool psci_tos_resident_on(int cpu)
 55{
 56	return cpu == resident_cpu;
 57}
 58
 
 
 
 
 
 59typedef unsigned long (psci_fn)(unsigned long, unsigned long,
 60				unsigned long, unsigned long);
 61static psci_fn *invoke_psci_fn;
 62
 63static struct psci_0_1_function_ids psci_0_1_function_ids;
 
 
 
 
 
 
 64
 65struct 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
 79static u32 psci_cpu_suspend_feature;
 80static bool psci_system_reset2_supported;
 81
 82static 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
 88bool psci_has_osi_support(void)
 89{
 90	return psci_cpu_suspend_feature & PSCI_1_0_OS_INITIATED;
 91}
 92
 93static 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
102bool 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
111static __always_inline unsigned long
112__invoke_psci_fn_hvc(unsigned long function_id,
113		     unsigned long arg0, unsigned long arg1,
114		     unsigned long arg2)
115{
116	struct arm_smccc_res res;
117
118	arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
119	return res.a0;
120}
121
122static __always_inline unsigned long
123__invoke_psci_fn_smc(unsigned long function_id,
124		     unsigned long arg0, unsigned long arg1,
125		     unsigned long arg2)
126{
127	struct arm_smccc_res res;
128
129	arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
130	return res.a0;
131}
132
133static __always_inline int psci_to_linux_errno(int errno)
134{
135	switch (errno) {
136	case PSCI_RET_SUCCESS:
137		return 0;
138	case PSCI_RET_NOT_SUPPORTED:
139		return -EOPNOTSUPP;
140	case PSCI_RET_INVALID_PARAMS:
141	case PSCI_RET_INVALID_ADDRESS:
142		return -EINVAL;
143	case PSCI_RET_DENIED:
144		return -EPERM;
145	}
146
147	return -EINVAL;
148}
149
150static u32 psci_0_1_get_version(void)
151{
152	return PSCI_VERSION(0, 1);
153}
154
155static u32 psci_0_2_get_version(void)
156{
157	return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
158}
159
160int psci_set_osi_mode(bool enable)
161{
162	unsigned long suspend_mode;
163	int err;
164
165	suspend_mode = enable ? PSCI_1_0_SUSPEND_MODE_OSI :
166			PSCI_1_0_SUSPEND_MODE_PC;
167
168	err = invoke_psci_fn(PSCI_1_0_FN_SET_SUSPEND_MODE, suspend_mode, 0, 0);
169	if (err < 0)
170		pr_info(FW_BUG "failed to set %s mode: %d\n",
171				enable ? "OSI" : "PC", err);
172	return psci_to_linux_errno(err);
173}
174
175static __always_inline int
176__psci_cpu_suspend(u32 fn, u32 state, unsigned long entry_point)
177{
178	int err;
 
179
 
180	err = invoke_psci_fn(fn, state, entry_point, 0);
181	return psci_to_linux_errno(err);
182}
183
184static __always_inline int
185psci_0_1_cpu_suspend(u32 state, unsigned long entry_point)
186{
187	return __psci_cpu_suspend(psci_0_1_function_ids.cpu_suspend,
188				  state, entry_point);
189}
190
191static __always_inline int
192psci_0_2_cpu_suspend(u32 state, unsigned long entry_point)
193{
194	return __psci_cpu_suspend(PSCI_FN_NATIVE(0_2, CPU_SUSPEND),
195				  state, entry_point);
196}
197
198static int __psci_cpu_off(u32 fn, u32 state)
199{
200	int err;
 
201
 
202	err = invoke_psci_fn(fn, state, 0, 0);
203	return psci_to_linux_errno(err);
204}
205
206static int psci_0_1_cpu_off(u32 state)
207{
208	return __psci_cpu_off(psci_0_1_function_ids.cpu_off, state);
209}
210
211static int psci_0_2_cpu_off(u32 state)
212{
213	return __psci_cpu_off(PSCI_0_2_FN_CPU_OFF, state);
214}
215
216static int __psci_cpu_on(u32 fn, unsigned long cpuid, unsigned long entry_point)
217{
218	int err;
 
219
 
220	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
221	return psci_to_linux_errno(err);
222}
223
224static int psci_0_1_cpu_on(unsigned long cpuid, unsigned long entry_point)
225{
226	return __psci_cpu_on(psci_0_1_function_ids.cpu_on, cpuid, entry_point);
227}
228
229static int psci_0_2_cpu_on(unsigned long cpuid, unsigned long entry_point)
230{
231	return __psci_cpu_on(PSCI_FN_NATIVE(0_2, CPU_ON), cpuid, entry_point);
232}
233
234static int __psci_migrate(u32 fn, unsigned long cpuid)
235{
236	int err;
 
237
 
238	err = invoke_psci_fn(fn, cpuid, 0, 0);
239	return psci_to_linux_errno(err);
240}
241
242static int psci_0_1_migrate(unsigned long cpuid)
243{
244	return __psci_migrate(psci_0_1_function_ids.migrate, cpuid);
245}
246
247static int psci_0_2_migrate(unsigned long cpuid)
248{
249	return __psci_migrate(PSCI_FN_NATIVE(0_2, MIGRATE), cpuid);
250}
251
252static int psci_affinity_info(unsigned long target_affinity,
253		unsigned long lowest_affinity_level)
254{
255	return invoke_psci_fn(PSCI_FN_NATIVE(0_2, AFFINITY_INFO),
256			      target_affinity, lowest_affinity_level, 0);
257}
258
259static int psci_migrate_info_type(void)
260{
261	return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
262}
263
264static unsigned long psci_migrate_info_up_cpu(void)
265{
266	return invoke_psci_fn(PSCI_FN_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
267			      0, 0, 0);
268}
269
270static void set_conduit(enum arm_smccc_conduit conduit)
271{
272	switch (conduit) {
273	case SMCCC_CONDUIT_HVC:
274		invoke_psci_fn = __invoke_psci_fn_hvc;
275		break;
276	case SMCCC_CONDUIT_SMC:
277		invoke_psci_fn = __invoke_psci_fn_smc;
278		break;
279	default:
280		WARN(1, "Unexpected PSCI conduit %d\n", conduit);
281	}
282
283	psci_conduit = conduit;
284}
285
286static int get_set_conduit_method(const struct device_node *np)
287{
288	const char *method;
289
290	pr_info("probing for conduit method from DT.\n");
291
292	if (of_property_read_string(np, "method", &method)) {
293		pr_warn("missing \"method\" property\n");
294		return -ENXIO;
295	}
296
297	if (!strcmp("hvc", method)) {
298		set_conduit(SMCCC_CONDUIT_HVC);
299	} else if (!strcmp("smc", method)) {
300		set_conduit(SMCCC_CONDUIT_SMC);
301	} else {
302		pr_warn("invalid \"method\" property: %s\n", method);
303		return -EINVAL;
304	}
305	return 0;
306}
307
308static int psci_sys_reset(struct notifier_block *nb, unsigned long action,
309			  void *data)
310{
311	if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&
312	    psci_system_reset2_supported) {
313		/*
314		 * reset_type[31] = 0 (architectural)
315		 * reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
316		 * cookie = 0 (ignored by the implementation)
317		 */
318		invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);
319	} else {
320		invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
321	}
322
323	return NOTIFY_DONE;
324}
325
326static struct notifier_block psci_sys_reset_nb = {
327	.notifier_call = psci_sys_reset,
328	.priority = 129,
329};
330
331static void psci_sys_poweroff(void)
332{
333	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
334}
335
336static int psci_features(u32 psci_func_id)
337{
338	return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
339			      psci_func_id, 0, 0);
340}
341
342#ifdef CONFIG_DEBUG_FS
343
344#define PSCI_ID(ver, _name) \
345	{ .fn = PSCI_##ver##_FN_##_name, .name = #_name, }
346#define PSCI_ID_NATIVE(ver, _name) \
347	{ .fn = PSCI_FN_NATIVE(ver, _name), .name = #_name, }
348
349/* A table of all optional functions */
350static const struct {
351	u32 fn;
352	const char *name;
353} psci_fn_ids[] = {
354	PSCI_ID_NATIVE(0_2, MIGRATE),
355	PSCI_ID(0_2, MIGRATE_INFO_TYPE),
356	PSCI_ID_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
357	PSCI_ID(1_0, CPU_FREEZE),
358	PSCI_ID_NATIVE(1_0, CPU_DEFAULT_SUSPEND),
359	PSCI_ID_NATIVE(1_0, NODE_HW_STATE),
360	PSCI_ID_NATIVE(1_0, SYSTEM_SUSPEND),
361	PSCI_ID(1_0, SET_SUSPEND_MODE),
362	PSCI_ID_NATIVE(1_0, STAT_RESIDENCY),
363	PSCI_ID_NATIVE(1_0, STAT_COUNT),
364	PSCI_ID_NATIVE(1_1, SYSTEM_RESET2),
365	PSCI_ID(1_1, MEM_PROTECT),
366	PSCI_ID_NATIVE(1_1, MEM_PROTECT_CHECK_RANGE),
367};
368
369static int psci_debugfs_read(struct seq_file *s, void *data)
370{
371	int feature, type, i;
372	u32 ver;
373
374	ver = psci_ops.get_version();
375	seq_printf(s, "PSCIv%d.%d\n",
376		   PSCI_VERSION_MAJOR(ver),
377		   PSCI_VERSION_MINOR(ver));
378
379	/* PSCI_FEATURES is available only starting from 1.0 */
380	if (PSCI_VERSION_MAJOR(ver) < 1)
381		return 0;
382
383	feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
384	if (feature != PSCI_RET_NOT_SUPPORTED) {
385		ver = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
386		seq_printf(s, "SMC Calling Convention v%d.%d\n",
387			   PSCI_VERSION_MAJOR(ver),
388			   PSCI_VERSION_MINOR(ver));
389	} else {
390		seq_puts(s, "SMC Calling Convention v1.0 is assumed\n");
391	}
392
393	feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND));
394	if (feature < 0) {
395		seq_printf(s, "PSCI_FEATURES(CPU_SUSPEND) error (%d)\n", feature);
396	} else {
397		seq_printf(s, "OSI is %ssupported\n",
398			   (feature & BIT(0)) ? "" : "not ");
399		seq_printf(s, "%s StateID format is used\n",
400			   (feature & BIT(1)) ? "Extended" : "Original");
401	}
402
403	type = psci_ops.migrate_info_type();
404	if (type == PSCI_0_2_TOS_UP_MIGRATE ||
405	    type == PSCI_0_2_TOS_UP_NO_MIGRATE) {
406		unsigned long cpuid;
407
408		seq_printf(s, "Trusted OS %smigrate capable\n",
409			   type == PSCI_0_2_TOS_UP_NO_MIGRATE ? "not " : "");
410		cpuid = psci_migrate_info_up_cpu();
411		seq_printf(s, "Trusted OS resident on physical CPU 0x%lx (#%d)\n",
412			   cpuid, resident_cpu);
413	} else if (type == PSCI_0_2_TOS_MP) {
414		seq_puts(s, "Trusted OS migration not required\n");
415	} else {
416		if (type != PSCI_RET_NOT_SUPPORTED)
417			seq_printf(s, "MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
418	}
419
420	for (i = 0; i < ARRAY_SIZE(psci_fn_ids); i++) {
421		feature = psci_features(psci_fn_ids[i].fn);
422		if (feature == PSCI_RET_NOT_SUPPORTED)
423			continue;
424		if (feature < 0)
425			seq_printf(s, "PSCI_FEATURES(%s) error (%d)\n",
426				   psci_fn_ids[i].name, feature);
427		else
428			seq_printf(s, "%s is supported\n", psci_fn_ids[i].name);
429	}
430
431	return 0;
432}
433
434static int psci_debugfs_open(struct inode *inode, struct file *f)
435{
436	return single_open(f, psci_debugfs_read, NULL);
437}
438
439static const struct file_operations psci_debugfs_ops = {
440	.owner = THIS_MODULE,
441	.open = psci_debugfs_open,
442	.release = single_release,
443	.read = seq_read,
444	.llseek = seq_lseek
445};
446
447static int __init psci_debugfs_init(void)
448{
449	if (!invoke_psci_fn || !psci_ops.get_version)
450		return 0;
451
452	return PTR_ERR_OR_ZERO(debugfs_create_file("psci", 0444, NULL, NULL,
453						   &psci_debugfs_ops));
454}
455late_initcall(psci_debugfs_init)
456#endif
457
458#ifdef CONFIG_CPU_IDLE
459static noinstr int psci_suspend_finisher(unsigned long state)
460{
461	u32 power_state = state;
462	phys_addr_t pa_cpu_resume;
463
464	pa_cpu_resume = __pa_symbol_nodebug((unsigned long)cpu_resume);
465
466	return psci_ops.cpu_suspend(power_state, pa_cpu_resume);
467}
468
469int psci_cpu_suspend_enter(u32 state)
470{
471	int ret;
472
473	if (!psci_power_state_loses_context(state)) {
474		struct arm_cpuidle_irq_context context;
475
476		ct_cpuidle_enter();
477		arm_cpuidle_save_irq_context(&context);
478		ret = psci_ops.cpu_suspend(state, 0);
479		arm_cpuidle_restore_irq_context(&context);
480		ct_cpuidle_exit();
481	} else {
482		/*
483		 * ARM64 cpu_suspend() wants to do ct_cpuidle_*() itself.
484		 */
485		if (!IS_ENABLED(CONFIG_ARM64))
486			ct_cpuidle_enter();
487
488		ret = cpu_suspend(state, psci_suspend_finisher);
489
490		if (!IS_ENABLED(CONFIG_ARM64))
491			ct_cpuidle_exit();
492	}
493
494	return ret;
495}
496#endif
497
498static int psci_system_suspend(unsigned long unused)
499{
500	phys_addr_t pa_cpu_resume = __pa_symbol(cpu_resume);
501
502	return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
503			      pa_cpu_resume, 0, 0);
504}
505
506static int psci_system_suspend_enter(suspend_state_t state)
507{
508	return cpu_suspend(0, psci_system_suspend);
509}
510
511static const struct platform_suspend_ops psci_suspend_ops = {
512	.valid          = suspend_valid_only_mem,
513	.enter          = psci_system_suspend_enter,
514};
515
516static void __init psci_init_system_reset2(void)
517{
518	int ret;
519
520	ret = psci_features(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2));
521
522	if (ret != PSCI_RET_NOT_SUPPORTED)
523		psci_system_reset2_supported = true;
524}
525
526static void __init psci_init_system_suspend(void)
527{
528	int ret;
529
530	if (!IS_ENABLED(CONFIG_SUSPEND))
531		return;
532
533	ret = psci_features(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND));
534
535	if (ret != PSCI_RET_NOT_SUPPORTED)
536		suspend_set_ops(&psci_suspend_ops);
537}
538
539static void __init psci_init_cpu_suspend(void)
540{
541	int feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND));
542
543	if (feature != PSCI_RET_NOT_SUPPORTED)
544		psci_cpu_suspend_feature = feature;
545}
546
547/*
548 * Detect the presence of a resident Trusted OS which may cause CPU_OFF to
549 * return DENIED (which would be fatal).
550 */
551static void __init psci_init_migrate(void)
552{
553	unsigned long cpuid;
554	int type, cpu = -1;
555
556	type = psci_ops.migrate_info_type();
557
558	if (type == PSCI_0_2_TOS_MP) {
559		pr_info("Trusted OS migration not required\n");
560		return;
561	}
562
563	if (type == PSCI_RET_NOT_SUPPORTED) {
564		pr_info("MIGRATE_INFO_TYPE not supported.\n");
565		return;
566	}
567
568	if (type != PSCI_0_2_TOS_UP_MIGRATE &&
569	    type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
570		pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
571		return;
572	}
573
574	cpuid = psci_migrate_info_up_cpu();
575	if (cpuid & ~MPIDR_HWID_BITMASK) {
576		pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
577			cpuid);
578		return;
579	}
580
581	cpu = get_logical_index(cpuid);
582	resident_cpu = cpu >= 0 ? cpu : -1;
583
584	pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
585}
586
587static void __init psci_init_smccc(void)
588{
589	u32 ver = ARM_SMCCC_VERSION_1_0;
590	int feature;
591
592	feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
593
594	if (feature != PSCI_RET_NOT_SUPPORTED) {
595		u32 ret;
596		ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
597		if (ret >= ARM_SMCCC_VERSION_1_1) {
598			arm_smccc_version_init(ret, psci_conduit);
599			ver = ret;
600		}
601	}
602
603	/*
604	 * Conveniently, the SMCCC and PSCI versions are encoded the
605	 * same way. No, this isn't accidental.
606	 */
607	pr_info("SMC Calling Convention v%d.%d\n",
608		PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver));
609
610}
611
612static void __init psci_0_2_set_functions(void)
613{
614	pr_info("Using standard PSCI v0.2 function IDs\n");
 
615
616	psci_ops = (struct psci_operations){
617		.get_version = psci_0_2_get_version,
618		.cpu_suspend = psci_0_2_cpu_suspend,
619		.cpu_off = psci_0_2_cpu_off,
620		.cpu_on = psci_0_2_cpu_on,
621		.migrate = psci_0_2_migrate,
622		.affinity_info = psci_affinity_info,
623		.migrate_info_type = psci_migrate_info_type,
624	};
625
626	register_restart_handler(&psci_sys_reset_nb);
 
 
 
 
 
 
 
627
628	pm_power_off = psci_sys_poweroff;
629}
630
631/*
632 * Probe function for PSCI firmware versions >= 0.2
633 */
634static int __init psci_probe(void)
635{
636	u32 ver = psci_0_2_get_version();
637
638	pr_info("PSCIv%d.%d detected in firmware.\n",
639			PSCI_VERSION_MAJOR(ver),
640			PSCI_VERSION_MINOR(ver));
641
642	if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
643		pr_err("Conflicting PSCI version detected.\n");
644		return -EINVAL;
645	}
646
647	psci_0_2_set_functions();
648
649	psci_init_migrate();
650
651	if (PSCI_VERSION_MAJOR(ver) >= 1) {
652		psci_init_smccc();
653		psci_init_cpu_suspend();
654		psci_init_system_suspend();
655		psci_init_system_reset2();
656		kvm_init_hyp_services();
657	}
658
659	return 0;
660}
661
662typedef int (*psci_initcall_t)(const struct device_node *);
663
664/*
665 * PSCI init function for PSCI versions >=0.2
666 *
667 * Probe based on PSCI PSCI_VERSION function
668 */
669static int __init psci_0_2_init(const struct device_node *np)
670{
671	int err;
672
673	err = get_set_conduit_method(np);
674	if (err)
675		return err;
676
677	/*
678	 * Starting with v0.2, the PSCI specification introduced a call
679	 * (PSCI_VERSION) that allows probing the firmware version, so
680	 * that PSCI function IDs and version specific initialization
681	 * can be carried out according to the specific version reported
682	 * by firmware
683	 */
684	return psci_probe();
685}
686
687/*
688 * PSCI < v0.2 get PSCI Function IDs via DT.
689 */
690static int __init psci_0_1_init(const struct device_node *np)
691{
692	u32 id;
693	int err;
694
695	err = get_set_conduit_method(np);
696	if (err)
697		return err;
698
699	pr_info("Using PSCI v0.1 Function IDs from DT\n");
700
701	psci_ops.get_version = psci_0_1_get_version;
702
703	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
704		psci_0_1_function_ids.cpu_suspend = id;
705		psci_ops.cpu_suspend = psci_0_1_cpu_suspend;
706	}
707
708	if (!of_property_read_u32(np, "cpu_off", &id)) {
709		psci_0_1_function_ids.cpu_off = id;
710		psci_ops.cpu_off = psci_0_1_cpu_off;
711	}
712
713	if (!of_property_read_u32(np, "cpu_on", &id)) {
714		psci_0_1_function_ids.cpu_on = id;
715		psci_ops.cpu_on = psci_0_1_cpu_on;
716	}
717
718	if (!of_property_read_u32(np, "migrate", &id)) {
719		psci_0_1_function_ids.migrate = id;
720		psci_ops.migrate = psci_0_1_migrate;
721	}
722
723	return 0;
724}
725
726static int __init psci_1_0_init(const struct device_node *np)
727{
728	int err;
729
730	err = psci_0_2_init(np);
731	if (err)
732		return err;
733
734	if (psci_has_osi_support()) {
735		pr_info("OSI mode supported.\n");
736
737		/* Default to PC mode. */
738		psci_set_osi_mode(false);
739	}
740
741	return 0;
742}
743
744static const struct of_device_id psci_of_match[] __initconst = {
745	{ .compatible = "arm,psci",	.data = psci_0_1_init},
746	{ .compatible = "arm,psci-0.2",	.data = psci_0_2_init},
747	{ .compatible = "arm,psci-1.0",	.data = psci_1_0_init},
748	{},
749};
750
751int __init psci_dt_init(void)
752{
753	struct device_node *np;
754	const struct of_device_id *matched_np;
755	psci_initcall_t init_fn;
756	int ret;
757
758	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
759
760	if (!np || !of_device_is_available(np))
761		return -ENODEV;
762
763	init_fn = (psci_initcall_t)matched_np->data;
764	ret = init_fn(np);
765
766	of_node_put(np);
767	return ret;
768}
769
770#ifdef CONFIG_ACPI
771/*
772 * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
773 * explicitly clarified in SBBR
774 */
775int __init psci_acpi_init(void)
776{
777	if (!acpi_psci_present()) {
778		pr_info("is not implemented in ACPI.\n");
779		return -EOPNOTSUPP;
780	}
781
782	pr_info("probing for conduit method from ACPI.\n");
783
784	if (acpi_psci_use_hvc())
785		set_conduit(SMCCC_CONDUIT_HVC);
786	else
787		set_conduit(SMCCC_CONDUIT_SMC);
788
789	return psci_probe();
790}
791#endif
v5.4
  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/errno.h>
 13#include <linux/linkage.h>
 14#include <linux/of.h>
 15#include <linux/pm.h>
 16#include <linux/printk.h>
 17#include <linux/psci.h>
 18#include <linux/reboot.h>
 19#include <linux/slab.h>
 20#include <linux/suspend.h>
 21
 22#include <uapi/linux/psci.h>
 23
 24#include <asm/cpuidle.h>
 25#include <asm/cputype.h>
 
 26#include <asm/system_misc.h>
 27#include <asm/smp_plat.h>
 28#include <asm/suspend.h>
 29
 30/*
 31 * While a 64-bit OS can make calls with SMC32 calling conventions, for some
 32 * calls it is necessary to use SMC64 to pass or return 64-bit values.
 33 * For such calls PSCI_FN_NATIVE(version, name) will choose the appropriate
 34 * (native-width) function ID.
 35 */
 36#ifdef CONFIG_64BIT
 37#define PSCI_FN_NATIVE(version, name)	PSCI_##version##_FN64_##name
 38#else
 39#define PSCI_FN_NATIVE(version, name)	PSCI_##version##_FN_##name
 40#endif
 41
 42/*
 43 * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
 44 * calls to its resident CPU, so we must avoid issuing those. We never migrate
 45 * a Trusted OS even if it claims to be capable of migration -- doing so will
 46 * require cooperation with a Trusted OS driver.
 47 */
 48static int resident_cpu = -1;
 
 
 49
 50bool psci_tos_resident_on(int cpu)
 51{
 52	return cpu == resident_cpu;
 53}
 54
 55struct psci_operations psci_ops = {
 56	.conduit = PSCI_CONDUIT_NONE,
 57	.smccc_version = SMCCC_VERSION_1_0,
 58};
 59
 60typedef unsigned long (psci_fn)(unsigned long, unsigned long,
 61				unsigned long, unsigned long);
 62static psci_fn *invoke_psci_fn;
 63
 64enum psci_function {
 65	PSCI_FN_CPU_SUSPEND,
 66	PSCI_FN_CPU_ON,
 67	PSCI_FN_CPU_OFF,
 68	PSCI_FN_MIGRATE,
 69	PSCI_FN_MAX,
 70};
 71
 72static u32 psci_function_id[PSCI_FN_MAX];
 
 
 
 73
 74#define PSCI_0_2_POWER_STATE_MASK		\
 75				(PSCI_0_2_POWER_STATE_ID_MASK | \
 76				PSCI_0_2_POWER_STATE_TYPE_MASK | \
 77				PSCI_0_2_POWER_STATE_AFFL_MASK)
 78
 79#define PSCI_1_0_EXT_POWER_STATE_MASK		\
 80				(PSCI_1_0_EXT_POWER_STATE_ID_MASK | \
 81				PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)
 82
 83static u32 psci_cpu_suspend_feature;
 84static bool psci_system_reset2_supported;
 85
 86static inline bool psci_has_ext_power_state(void)
 87{
 88	return psci_cpu_suspend_feature &
 89				PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
 90}
 91
 92static inline bool psci_has_osi_support(void)
 93{
 94	return psci_cpu_suspend_feature & PSCI_1_0_OS_INITIATED;
 95}
 96
 97static inline bool psci_power_state_loses_context(u32 state)
 98{
 99	const u32 mask = psci_has_ext_power_state() ?
100					PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :
101					PSCI_0_2_POWER_STATE_TYPE_MASK;
102
103	return state & mask;
104}
105
106bool psci_power_state_is_valid(u32 state)
107{
108	const u32 valid_mask = psci_has_ext_power_state() ?
109			       PSCI_1_0_EXT_POWER_STATE_MASK :
110			       PSCI_0_2_POWER_STATE_MASK;
111
112	return !(state & ~valid_mask);
113}
114
115static unsigned long __invoke_psci_fn_hvc(unsigned long function_id,
116			unsigned long arg0, unsigned long arg1,
117			unsigned long arg2)
 
118{
119	struct arm_smccc_res res;
120
121	arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
122	return res.a0;
123}
124
125static unsigned long __invoke_psci_fn_smc(unsigned long function_id,
126			unsigned long arg0, unsigned long arg1,
127			unsigned long arg2)
 
128{
129	struct arm_smccc_res res;
130
131	arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
132	return res.a0;
133}
134
135static int psci_to_linux_errno(int errno)
136{
137	switch (errno) {
138	case PSCI_RET_SUCCESS:
139		return 0;
140	case PSCI_RET_NOT_SUPPORTED:
141		return -EOPNOTSUPP;
142	case PSCI_RET_INVALID_PARAMS:
143	case PSCI_RET_INVALID_ADDRESS:
144		return -EINVAL;
145	case PSCI_RET_DENIED:
146		return -EPERM;
147	};
148
149	return -EINVAL;
150}
151
152static u32 psci_get_version(void)
 
 
 
 
 
153{
154	return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
155}
156
157static int psci_cpu_suspend(u32 state, unsigned long entry_point)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
158{
159	int err;
160	u32 fn;
161
162	fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
163	err = invoke_psci_fn(fn, state, entry_point, 0);
164	return psci_to_linux_errno(err);
165}
166
167static int psci_cpu_off(u32 state)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
168{
169	int err;
170	u32 fn;
171
172	fn = psci_function_id[PSCI_FN_CPU_OFF];
173	err = invoke_psci_fn(fn, state, 0, 0);
174	return psci_to_linux_errno(err);
175}
176
177static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
 
 
 
 
 
 
 
 
 
 
178{
179	int err;
180	u32 fn;
181
182	fn = psci_function_id[PSCI_FN_CPU_ON];
183	err = invoke_psci_fn(fn, cpuid, entry_point, 0);
184	return psci_to_linux_errno(err);
185}
186
187static int psci_migrate(unsigned long cpuid)
 
 
 
 
 
 
 
 
 
 
188{
189	int err;
190	u32 fn;
191
192	fn = psci_function_id[PSCI_FN_MIGRATE];
193	err = invoke_psci_fn(fn, cpuid, 0, 0);
194	return psci_to_linux_errno(err);
195}
196
 
 
 
 
 
 
 
 
 
 
197static int psci_affinity_info(unsigned long target_affinity,
198		unsigned long lowest_affinity_level)
199{
200	return invoke_psci_fn(PSCI_FN_NATIVE(0_2, AFFINITY_INFO),
201			      target_affinity, lowest_affinity_level, 0);
202}
203
204static int psci_migrate_info_type(void)
205{
206	return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
207}
208
209static unsigned long psci_migrate_info_up_cpu(void)
210{
211	return invoke_psci_fn(PSCI_FN_NATIVE(0_2, MIGRATE_INFO_UP_CPU),
212			      0, 0, 0);
213}
214
215static void set_conduit(enum psci_conduit conduit)
216{
217	switch (conduit) {
218	case PSCI_CONDUIT_HVC:
219		invoke_psci_fn = __invoke_psci_fn_hvc;
220		break;
221	case PSCI_CONDUIT_SMC:
222		invoke_psci_fn = __invoke_psci_fn_smc;
223		break;
224	default:
225		WARN(1, "Unexpected PSCI conduit %d\n", conduit);
226	}
227
228	psci_ops.conduit = conduit;
229}
230
231static int get_set_conduit_method(struct device_node *np)
232{
233	const char *method;
234
235	pr_info("probing for conduit method from DT.\n");
236
237	if (of_property_read_string(np, "method", &method)) {
238		pr_warn("missing \"method\" property\n");
239		return -ENXIO;
240	}
241
242	if (!strcmp("hvc", method)) {
243		set_conduit(PSCI_CONDUIT_HVC);
244	} else if (!strcmp("smc", method)) {
245		set_conduit(PSCI_CONDUIT_SMC);
246	} else {
247		pr_warn("invalid \"method\" property: %s\n", method);
248		return -EINVAL;
249	}
250	return 0;
251}
252
253static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
 
254{
255	if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) &&
256	    psci_system_reset2_supported) {
257		/*
258		 * reset_type[31] = 0 (architectural)
259		 * reset_type[30:0] = 0 (SYSTEM_WARM_RESET)
260		 * cookie = 0 (ignored by the implementation)
261		 */
262		invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0);
263	} else {
264		invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
265	}
 
 
266}
267
 
 
 
 
 
268static void psci_sys_poweroff(void)
269{
270	invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
271}
272
273static int __init psci_features(u32 psci_func_id)
274{
275	return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
276			      psci_func_id, 0, 0);
277}
278
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
279#ifdef CONFIG_CPU_IDLE
280static int psci_suspend_finisher(unsigned long state)
281{
282	u32 power_state = state;
 
283
284	return psci_ops.cpu_suspend(power_state, __pa_symbol(cpu_resume));
 
 
285}
286
287int psci_cpu_suspend_enter(u32 state)
288{
289	int ret;
290
291	if (!psci_power_state_loses_context(state))
 
 
 
 
292		ret = psci_ops.cpu_suspend(state, 0);
293	else
 
 
 
 
 
 
 
 
294		ret = cpu_suspend(state, psci_suspend_finisher);
295
 
 
 
 
296	return ret;
297}
298#endif
299
300static int psci_system_suspend(unsigned long unused)
301{
 
 
302	return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND),
303			      __pa_symbol(cpu_resume), 0, 0);
304}
305
306static int psci_system_suspend_enter(suspend_state_t state)
307{
308	return cpu_suspend(0, psci_system_suspend);
309}
310
311static const struct platform_suspend_ops psci_suspend_ops = {
312	.valid          = suspend_valid_only_mem,
313	.enter          = psci_system_suspend_enter,
314};
315
316static void __init psci_init_system_reset2(void)
317{
318	int ret;
319
320	ret = psci_features(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2));
321
322	if (ret != PSCI_RET_NOT_SUPPORTED)
323		psci_system_reset2_supported = true;
324}
325
326static void __init psci_init_system_suspend(void)
327{
328	int ret;
329
330	if (!IS_ENABLED(CONFIG_SUSPEND))
331		return;
332
333	ret = psci_features(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND));
334
335	if (ret != PSCI_RET_NOT_SUPPORTED)
336		suspend_set_ops(&psci_suspend_ops);
337}
338
339static void __init psci_init_cpu_suspend(void)
340{
341	int feature = psci_features(psci_function_id[PSCI_FN_CPU_SUSPEND]);
342
343	if (feature != PSCI_RET_NOT_SUPPORTED)
344		psci_cpu_suspend_feature = feature;
345}
346
347/*
348 * Detect the presence of a resident Trusted OS which may cause CPU_OFF to
349 * return DENIED (which would be fatal).
350 */
351static void __init psci_init_migrate(void)
352{
353	unsigned long cpuid;
354	int type, cpu = -1;
355
356	type = psci_ops.migrate_info_type();
357
358	if (type == PSCI_0_2_TOS_MP) {
359		pr_info("Trusted OS migration not required\n");
360		return;
361	}
362
363	if (type == PSCI_RET_NOT_SUPPORTED) {
364		pr_info("MIGRATE_INFO_TYPE not supported.\n");
365		return;
366	}
367
368	if (type != PSCI_0_2_TOS_UP_MIGRATE &&
369	    type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
370		pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
371		return;
372	}
373
374	cpuid = psci_migrate_info_up_cpu();
375	if (cpuid & ~MPIDR_HWID_BITMASK) {
376		pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
377			cpuid);
378		return;
379	}
380
381	cpu = get_logical_index(cpuid);
382	resident_cpu = cpu >= 0 ? cpu : -1;
383
384	pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
385}
386
387static void __init psci_init_smccc(void)
388{
389	u32 ver = ARM_SMCCC_VERSION_1_0;
390	int feature;
391
392	feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
393
394	if (feature != PSCI_RET_NOT_SUPPORTED) {
395		u32 ret;
396		ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
397		if (ret == ARM_SMCCC_VERSION_1_1) {
398			psci_ops.smccc_version = SMCCC_VERSION_1_1;
399			ver = ret;
400		}
401	}
402
403	/*
404	 * Conveniently, the SMCCC and PSCI versions are encoded the
405	 * same way. No, this isn't accidental.
406	 */
407	pr_info("SMC Calling Convention v%d.%d\n",
408		PSCI_VERSION_MAJOR(ver), PSCI_VERSION_MINOR(ver));
409
410}
411
412static void __init psci_0_2_set_functions(void)
413{
414	pr_info("Using standard PSCI v0.2 function IDs\n");
415	psci_ops.get_version = psci_get_version;
416
417	psci_function_id[PSCI_FN_CPU_SUSPEND] =
418					PSCI_FN_NATIVE(0_2, CPU_SUSPEND);
419	psci_ops.cpu_suspend = psci_cpu_suspend;
420
421	psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
422	psci_ops.cpu_off = psci_cpu_off;
423
424	psci_function_id[PSCI_FN_CPU_ON] = PSCI_FN_NATIVE(0_2, CPU_ON);
425	psci_ops.cpu_on = psci_cpu_on;
426
427	psci_function_id[PSCI_FN_MIGRATE] = PSCI_FN_NATIVE(0_2, MIGRATE);
428	psci_ops.migrate = psci_migrate;
429
430	psci_ops.affinity_info = psci_affinity_info;
431
432	psci_ops.migrate_info_type = psci_migrate_info_type;
433
434	arm_pm_restart = psci_sys_reset;
435
436	pm_power_off = psci_sys_poweroff;
437}
438
439/*
440 * Probe function for PSCI firmware versions >= 0.2
441 */
442static int __init psci_probe(void)
443{
444	u32 ver = psci_get_version();
445
446	pr_info("PSCIv%d.%d detected in firmware.\n",
447			PSCI_VERSION_MAJOR(ver),
448			PSCI_VERSION_MINOR(ver));
449
450	if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
451		pr_err("Conflicting PSCI version detected.\n");
452		return -EINVAL;
453	}
454
455	psci_0_2_set_functions();
456
457	psci_init_migrate();
458
459	if (PSCI_VERSION_MAJOR(ver) >= 1) {
460		psci_init_smccc();
461		psci_init_cpu_suspend();
462		psci_init_system_suspend();
463		psci_init_system_reset2();
 
464	}
465
466	return 0;
467}
468
469typedef int (*psci_initcall_t)(const struct device_node *);
470
471/*
472 * PSCI init function for PSCI versions >=0.2
473 *
474 * Probe based on PSCI PSCI_VERSION function
475 */
476static int __init psci_0_2_init(struct device_node *np)
477{
478	int err;
479
480	err = get_set_conduit_method(np);
481	if (err)
482		return err;
483
484	/*
485	 * Starting with v0.2, the PSCI specification introduced a call
486	 * (PSCI_VERSION) that allows probing the firmware version, so
487	 * that PSCI function IDs and version specific initialization
488	 * can be carried out according to the specific version reported
489	 * by firmware
490	 */
491	return psci_probe();
492}
493
494/*
495 * PSCI < v0.2 get PSCI Function IDs via DT.
496 */
497static int __init psci_0_1_init(struct device_node *np)
498{
499	u32 id;
500	int err;
501
502	err = get_set_conduit_method(np);
503	if (err)
504		return err;
505
506	pr_info("Using PSCI v0.1 Function IDs from DT\n");
507
 
 
508	if (!of_property_read_u32(np, "cpu_suspend", &id)) {
509		psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
510		psci_ops.cpu_suspend = psci_cpu_suspend;
511	}
512
513	if (!of_property_read_u32(np, "cpu_off", &id)) {
514		psci_function_id[PSCI_FN_CPU_OFF] = id;
515		psci_ops.cpu_off = psci_cpu_off;
516	}
517
518	if (!of_property_read_u32(np, "cpu_on", &id)) {
519		psci_function_id[PSCI_FN_CPU_ON] = id;
520		psci_ops.cpu_on = psci_cpu_on;
521	}
522
523	if (!of_property_read_u32(np, "migrate", &id)) {
524		psci_function_id[PSCI_FN_MIGRATE] = id;
525		psci_ops.migrate = psci_migrate;
526	}
527
528	return 0;
529}
530
531static int __init psci_1_0_init(struct device_node *np)
532{
533	int err;
534
535	err = psci_0_2_init(np);
536	if (err)
537		return err;
538
539	if (psci_has_osi_support())
540		pr_info("OSI mode supported.\n");
541
 
 
 
 
542	return 0;
543}
544
545static const struct of_device_id psci_of_match[] __initconst = {
546	{ .compatible = "arm,psci",	.data = psci_0_1_init},
547	{ .compatible = "arm,psci-0.2",	.data = psci_0_2_init},
548	{ .compatible = "arm,psci-1.0",	.data = psci_1_0_init},
549	{},
550};
551
552int __init psci_dt_init(void)
553{
554	struct device_node *np;
555	const struct of_device_id *matched_np;
556	psci_initcall_t init_fn;
557	int ret;
558
559	np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
560
561	if (!np || !of_device_is_available(np))
562		return -ENODEV;
563
564	init_fn = (psci_initcall_t)matched_np->data;
565	ret = init_fn(np);
566
567	of_node_put(np);
568	return ret;
569}
570
571#ifdef CONFIG_ACPI
572/*
573 * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
574 * explicitly clarified in SBBR
575 */
576int __init psci_acpi_init(void)
577{
578	if (!acpi_psci_present()) {
579		pr_info("is not implemented in ACPI.\n");
580		return -EOPNOTSUPP;
581	}
582
583	pr_info("probing for conduit method from ACPI.\n");
584
585	if (acpi_psci_use_hvc())
586		set_conduit(PSCI_CONDUIT_HVC);
587	else
588		set_conduit(PSCI_CONDUIT_SMC);
589
590	return psci_probe();
591}
592#endif