xref: /rk3399_ARM-atf/lib/psci/psci_common.c (revision 6311f63de02ee04d93016242977ade4727089de8)
1 /*
2  * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <arch.h>
8 #include <arch_helpers.h>
9 #include <assert.h>
10 #include <bl_common.h>
11 #include <context.h>
12 #include <context_mgmt.h>
13 #include <debug.h>
14 #include <platform.h>
15 #include <string.h>
16 #include <utils.h>
17 #include "psci_private.h"
18 
19 /*
20  * SPD power management operations, expected to be supplied by the registered
21  * SPD on successful SP initialization
22  */
23 const spd_pm_ops_t *psci_spd_pm;
24 
25 /*
26  * PSCI requested local power state map. This array is used to store the local
27  * power states requested by a CPU for power levels from level 1 to
28  * PLAT_MAX_PWR_LVL. It does not store the requested local power state for power
29  * level 0 (PSCI_CPU_PWR_LVL) as the requested and the target power state for a
30  * CPU are the same.
31  *
32  * During state coordination, the platform is passed an array containing the
33  * local states requested for a particular non cpu power domain by each cpu
34  * within the domain.
35  *
36  * TODO: Dense packing of the requested states will cause cache thrashing
37  * when multiple power domains write to it. If we allocate the requested
38  * states at each power level in a cache-line aligned per-domain memory,
39  * the cache thrashing can be avoided.
40  */
41 static plat_local_state_t
42 	psci_req_local_pwr_states[PLAT_MAX_PWR_LVL][PLATFORM_CORE_COUNT];
43 
44 
45 /*******************************************************************************
46  * Arrays that hold the platform's power domain tree information for state
47  * management of power domains.
48  * Each node in the array 'psci_non_cpu_pd_nodes' corresponds to a power domain
49  * which is an ancestor of a CPU power domain.
50  * Each node in the array 'psci_cpu_pd_nodes' corresponds to a cpu power domain
51  ******************************************************************************/
52 non_cpu_pd_node_t psci_non_cpu_pd_nodes[PSCI_NUM_NON_CPU_PWR_DOMAINS]
53 #if USE_COHERENT_MEM
54 __section("tzfw_coherent_mem")
55 #endif
56 ;
57 
58 /* Lock for PSCI state coordination */
59 DEFINE_PSCI_LOCK(psci_locks[PSCI_NUM_NON_CPU_PWR_DOMAINS]);
60 
61 cpu_pd_node_t psci_cpu_pd_nodes[PLATFORM_CORE_COUNT];
62 
63 /*******************************************************************************
64  * Pointer to functions exported by the platform to complete power mgmt. ops
65  ******************************************************************************/
66 const plat_psci_ops_t *psci_plat_pm_ops;
67 
68 /******************************************************************************
69  * Check that the maximum power level supported by the platform makes sense
70  *****************************************************************************/
71 CASSERT(PLAT_MAX_PWR_LVL <= PSCI_MAX_PWR_LVL && \
72 		PLAT_MAX_PWR_LVL >= PSCI_CPU_PWR_LVL, \
73 		assert_platform_max_pwrlvl_check);
74 
75 /*
76  * The plat_local_state used by the platform is one of these types: RUN,
77  * RETENTION and OFF. The platform can define further sub-states for each type
78  * apart from RUN. This categorization is done to verify the sanity of the
79  * psci_power_state passed by the platform and to print debug information. The
80  * categorization is done on the basis of the following conditions:
81  *
82  * 1. If (plat_local_state == 0) then the category is STATE_TYPE_RUN.
83  *
84  * 2. If (0 < plat_local_state <= PLAT_MAX_RET_STATE), then the category is
85  *    STATE_TYPE_RETN.
86  *
87  * 3. If (plat_local_state > PLAT_MAX_RET_STATE), then the category is
88  *    STATE_TYPE_OFF.
89  */
90 typedef enum plat_local_state_type {
91 	STATE_TYPE_RUN = 0,
92 	STATE_TYPE_RETN,
93 	STATE_TYPE_OFF
94 } plat_local_state_type_t;
95 
96 /* The macro used to categorize plat_local_state. */
97 #define find_local_state_type(plat_local_state)					\
98 		((plat_local_state) ? ((plat_local_state > PLAT_MAX_RET_STATE)	\
99 		? STATE_TYPE_OFF : STATE_TYPE_RETN)				\
100 		: STATE_TYPE_RUN)
101 
102 /******************************************************************************
103  * Check that the maximum retention level supported by the platform is less
104  * than the maximum off level.
105  *****************************************************************************/
106 CASSERT(PLAT_MAX_RET_STATE < PLAT_MAX_OFF_STATE, \
107 		assert_platform_max_off_and_retn_state_check);
108 
109 /******************************************************************************
110  * This function ensures that the power state parameter in a CPU_SUSPEND request
111  * is valid. If so, it returns the requested states for each power level.
112  *****************************************************************************/
113 int psci_validate_power_state(unsigned int power_state,
114 			      psci_power_state_t *state_info)
115 {
116 	/* Check SBZ bits in power state are zero */
117 	if (psci_check_power_state(power_state))
118 		return PSCI_E_INVALID_PARAMS;
119 
120 	assert(psci_plat_pm_ops->validate_power_state);
121 
122 	/* Validate the power_state using platform pm_ops */
123 	return psci_plat_pm_ops->validate_power_state(power_state, state_info);
124 }
125 
126 /******************************************************************************
127  * This function retrieves the `psci_power_state_t` for system suspend from
128  * the platform.
129  *****************************************************************************/
130 void psci_query_sys_suspend_pwrstate(psci_power_state_t *state_info)
131 {
132 	/*
133 	 * Assert that the required pm_ops hook is implemented to ensure that
134 	 * the capability detected during psci_setup() is valid.
135 	 */
136 	assert(psci_plat_pm_ops->get_sys_suspend_power_state);
137 
138 	/*
139 	 * Query the platform for the power_state required for system suspend
140 	 */
141 	psci_plat_pm_ops->get_sys_suspend_power_state(state_info);
142 }
143 
144 /*******************************************************************************
145  * This function verifies that the all the other cores in the system have been
146  * turned OFF and the current CPU is the last running CPU in the system.
147  * Returns 1 (true) if the current CPU is the last ON CPU or 0 (false)
148  * otherwise.
149  ******************************************************************************/
150 unsigned int psci_is_last_on_cpu(void)
151 {
152 	unsigned int cpu_idx, my_idx = plat_my_core_pos();
153 
154 	for (cpu_idx = 0; cpu_idx < PLATFORM_CORE_COUNT; cpu_idx++) {
155 		if (cpu_idx == my_idx) {
156 			assert(psci_get_aff_info_state() == AFF_STATE_ON);
157 			continue;
158 		}
159 
160 		if (psci_get_aff_info_state_by_idx(cpu_idx) != AFF_STATE_OFF)
161 			return 0;
162 	}
163 
164 	return 1;
165 }
166 
167 /*******************************************************************************
168  * Routine to return the maximum power level to traverse to after a cpu has
169  * been physically powered up. It is expected to be called immediately after
170  * reset from assembler code.
171  ******************************************************************************/
172 static unsigned int get_power_on_target_pwrlvl(void)
173 {
174 	unsigned int pwrlvl;
175 
176 	/*
177 	 * Assume that this cpu was suspended and retrieve its target power
178 	 * level. If it is invalid then it could only have been turned off
179 	 * earlier. PLAT_MAX_PWR_LVL will be the highest power level a
180 	 * cpu can be turned off to.
181 	 */
182 	pwrlvl = psci_get_suspend_pwrlvl();
183 	if (pwrlvl == PSCI_INVALID_PWR_LVL)
184 		pwrlvl = PLAT_MAX_PWR_LVL;
185 	return pwrlvl;
186 }
187 
188 /******************************************************************************
189  * Helper function to update the requested local power state array. This array
190  * does not store the requested state for the CPU power level. Hence an
191  * assertion is added to prevent us from accessing the wrong index.
192  *****************************************************************************/
193 static void psci_set_req_local_pwr_state(unsigned int pwrlvl,
194 					 unsigned int cpu_idx,
195 					 plat_local_state_t req_pwr_state)
196 {
197 	assert(pwrlvl > PSCI_CPU_PWR_LVL);
198 	psci_req_local_pwr_states[pwrlvl - 1][cpu_idx] = req_pwr_state;
199 }
200 
201 /******************************************************************************
202  * This function initializes the psci_req_local_pwr_states.
203  *****************************************************************************/
204 void psci_init_req_local_pwr_states(void)
205 {
206 	/* Initialize the requested state of all non CPU power domains as OFF */
207 	memset(&psci_req_local_pwr_states, PLAT_MAX_OFF_STATE,
208 			sizeof(psci_req_local_pwr_states));
209 }
210 
211 /******************************************************************************
212  * Helper function to return a reference to an array containing the local power
213  * states requested by each cpu for a power domain at 'pwrlvl'. The size of the
214  * array will be the number of cpu power domains of which this power domain is
215  * an ancestor. These requested states will be used to determine a suitable
216  * target state for this power domain during psci state coordination. An
217  * assertion is added to prevent us from accessing the CPU power level.
218  *****************************************************************************/
219 static plat_local_state_t *psci_get_req_local_pwr_states(unsigned int pwrlvl,
220 							 unsigned int cpu_idx)
221 {
222 	assert(pwrlvl > PSCI_CPU_PWR_LVL);
223 
224 	return &psci_req_local_pwr_states[pwrlvl - 1][cpu_idx];
225 }
226 
227 /*
228  * psci_non_cpu_pd_nodes can be placed either in normal memory or coherent
229  * memory.
230  *
231  * With !USE_COHERENT_MEM, psci_non_cpu_pd_nodes is placed in normal memory,
232  * it's accessed by both cached and non-cached participants. To serve the common
233  * minimum, perform a cache flush before read and after write so that non-cached
234  * participants operate on latest data in main memory.
235  *
236  * When USE_COHERENT_MEM is used, psci_non_cpu_pd_nodes is placed in coherent
237  * memory. With HW_ASSISTED_COHERENCY, all PSCI participants are cache-coherent.
238  * In both cases, no cache operations are required.
239  */
240 
241 /*
242  * Retrieve local state of non-CPU power domain node from a non-cached CPU,
243  * after any required cache maintenance operation.
244  */
245 static plat_local_state_t get_non_cpu_pd_node_local_state(
246 		unsigned int parent_idx)
247 {
248 #if !USE_COHERENT_MEM || !HW_ASSISTED_COHERENCY
249 	flush_dcache_range(
250 			(uintptr_t) &psci_non_cpu_pd_nodes[parent_idx],
251 			sizeof(psci_non_cpu_pd_nodes[parent_idx]));
252 #endif
253 	return psci_non_cpu_pd_nodes[parent_idx].local_state;
254 }
255 
256 /*
257  * Update local state of non-CPU power domain node from a cached CPU; perform
258  * any required cache maintenance operation afterwards.
259  */
260 static void set_non_cpu_pd_node_local_state(unsigned int parent_idx,
261 		plat_local_state_t state)
262 {
263 	psci_non_cpu_pd_nodes[parent_idx].local_state = state;
264 #if !USE_COHERENT_MEM || !HW_ASSISTED_COHERENCY
265 	flush_dcache_range(
266 			(uintptr_t) &psci_non_cpu_pd_nodes[parent_idx],
267 			sizeof(psci_non_cpu_pd_nodes[parent_idx]));
268 #endif
269 }
270 
271 /******************************************************************************
272  * Helper function to return the current local power state of each power domain
273  * from the current cpu power domain to its ancestor at the 'end_pwrlvl'. This
274  * function will be called after a cpu is powered on to find the local state
275  * each power domain has emerged from.
276  *****************************************************************************/
277 void psci_get_target_local_pwr_states(unsigned int end_pwrlvl,
278 				      psci_power_state_t *target_state)
279 {
280 	unsigned int parent_idx, lvl;
281 	plat_local_state_t *pd_state = target_state->pwr_domain_state;
282 
283 	pd_state[PSCI_CPU_PWR_LVL] = psci_get_cpu_local_state();
284 	parent_idx = psci_cpu_pd_nodes[plat_my_core_pos()].parent_node;
285 
286 	/* Copy the local power state from node to state_info */
287 	for (lvl = PSCI_CPU_PWR_LVL + 1; lvl <= end_pwrlvl; lvl++) {
288 		pd_state[lvl] = get_non_cpu_pd_node_local_state(parent_idx);
289 		parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
290 	}
291 
292 	/* Set the the higher levels to RUN */
293 	for (; lvl <= PLAT_MAX_PWR_LVL; lvl++)
294 		target_state->pwr_domain_state[lvl] = PSCI_LOCAL_STATE_RUN;
295 }
296 
297 /******************************************************************************
298  * Helper function to set the target local power state that each power domain
299  * from the current cpu power domain to its ancestor at the 'end_pwrlvl' will
300  * enter. This function will be called after coordination of requested power
301  * states has been done for each power level.
302  *****************************************************************************/
303 static void psci_set_target_local_pwr_states(unsigned int end_pwrlvl,
304 					const psci_power_state_t *target_state)
305 {
306 	unsigned int parent_idx, lvl;
307 	const plat_local_state_t *pd_state = target_state->pwr_domain_state;
308 
309 	psci_set_cpu_local_state(pd_state[PSCI_CPU_PWR_LVL]);
310 
311 	/*
312 	 * Need to flush as local_state might be accessed with Data Cache
313 	 * disabled during power on
314 	 */
315 	psci_flush_cpu_data(psci_svc_cpu_data.local_state);
316 
317 	parent_idx = psci_cpu_pd_nodes[plat_my_core_pos()].parent_node;
318 
319 	/* Copy the local_state from state_info */
320 	for (lvl = 1; lvl <= end_pwrlvl; lvl++) {
321 		set_non_cpu_pd_node_local_state(parent_idx, pd_state[lvl]);
322 		parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
323 	}
324 }
325 
326 
327 /*******************************************************************************
328  * PSCI helper function to get the parent nodes corresponding to a cpu_index.
329  ******************************************************************************/
330 void psci_get_parent_pwr_domain_nodes(unsigned int cpu_idx,
331 				      unsigned int end_lvl,
332 				      unsigned int node_index[])
333 {
334 	unsigned int parent_node = psci_cpu_pd_nodes[cpu_idx].parent_node;
335 	unsigned int i;
336 
337 	for (i = PSCI_CPU_PWR_LVL + 1; i <= end_lvl; i++) {
338 		*node_index++ = parent_node;
339 		parent_node = psci_non_cpu_pd_nodes[parent_node].parent_node;
340 	}
341 }
342 
343 /******************************************************************************
344  * This function is invoked post CPU power up and initialization. It sets the
345  * affinity info state, target power state and requested power state for the
346  * current CPU and all its ancestor power domains to RUN.
347  *****************************************************************************/
348 void psci_set_pwr_domains_to_run(unsigned int end_pwrlvl)
349 {
350 	unsigned int parent_idx, cpu_idx = plat_my_core_pos(), lvl;
351 	parent_idx = psci_cpu_pd_nodes[cpu_idx].parent_node;
352 
353 	/* Reset the local_state to RUN for the non cpu power domains. */
354 	for (lvl = PSCI_CPU_PWR_LVL + 1; lvl <= end_pwrlvl; lvl++) {
355 		set_non_cpu_pd_node_local_state(parent_idx,
356 				PSCI_LOCAL_STATE_RUN);
357 		psci_set_req_local_pwr_state(lvl,
358 					     cpu_idx,
359 					     PSCI_LOCAL_STATE_RUN);
360 		parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
361 	}
362 
363 	/* Set the affinity info state to ON */
364 	psci_set_aff_info_state(AFF_STATE_ON);
365 
366 	psci_set_cpu_local_state(PSCI_LOCAL_STATE_RUN);
367 	psci_flush_cpu_data(psci_svc_cpu_data);
368 }
369 
370 /******************************************************************************
371  * This function is passed the local power states requested for each power
372  * domain (state_info) between the current CPU domain and its ancestors until
373  * the target power level (end_pwrlvl). It updates the array of requested power
374  * states with this information.
375  *
376  * Then, for each level (apart from the CPU level) until the 'end_pwrlvl', it
377  * retrieves the states requested by all the cpus of which the power domain at
378  * that level is an ancestor. It passes this information to the platform to
379  * coordinate and return the target power state. If the target state for a level
380  * is RUN then subsequent levels are not considered. At the CPU level, state
381  * coordination is not required. Hence, the requested and the target states are
382  * the same.
383  *
384  * The 'state_info' is updated with the target state for each level between the
385  * CPU and the 'end_pwrlvl' and returned to the caller.
386  *
387  * This function will only be invoked with data cache enabled and while
388  * powering down a core.
389  *****************************************************************************/
390 void psci_do_state_coordination(unsigned int end_pwrlvl,
391 				psci_power_state_t *state_info)
392 {
393 	unsigned int lvl, parent_idx, cpu_idx = plat_my_core_pos();
394 	unsigned int start_idx, ncpus;
395 	plat_local_state_t target_state, *req_states;
396 
397 	assert(end_pwrlvl <= PLAT_MAX_PWR_LVL);
398 	parent_idx = psci_cpu_pd_nodes[cpu_idx].parent_node;
399 
400 	/* For level 0, the requested state will be equivalent
401 	   to target state */
402 	for (lvl = PSCI_CPU_PWR_LVL + 1; lvl <= end_pwrlvl; lvl++) {
403 
404 		/* First update the requested power state */
405 		psci_set_req_local_pwr_state(lvl, cpu_idx,
406 					     state_info->pwr_domain_state[lvl]);
407 
408 		/* Get the requested power states for this power level */
409 		start_idx = psci_non_cpu_pd_nodes[parent_idx].cpu_start_idx;
410 		req_states = psci_get_req_local_pwr_states(lvl, start_idx);
411 
412 		/*
413 		 * Let the platform coordinate amongst the requested states at
414 		 * this power level and return the target local power state.
415 		 */
416 		ncpus = psci_non_cpu_pd_nodes[parent_idx].ncpus;
417 		target_state = plat_get_target_pwr_state(lvl,
418 							 req_states,
419 							 ncpus);
420 
421 		state_info->pwr_domain_state[lvl] = target_state;
422 
423 		/* Break early if the negotiated target power state is RUN */
424 		if (is_local_state_run(state_info->pwr_domain_state[lvl]))
425 			break;
426 
427 		parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
428 	}
429 
430 	/*
431 	 * This is for cases when we break out of the above loop early because
432 	 * the target power state is RUN at a power level < end_pwlvl.
433 	 * We update the requested power state from state_info and then
434 	 * set the target state as RUN.
435 	 */
436 	for (lvl = lvl + 1; lvl <= end_pwrlvl; lvl++) {
437 		psci_set_req_local_pwr_state(lvl, cpu_idx,
438 					     state_info->pwr_domain_state[lvl]);
439 		state_info->pwr_domain_state[lvl] = PSCI_LOCAL_STATE_RUN;
440 
441 	}
442 
443 	/* Update the target state in the power domain nodes */
444 	psci_set_target_local_pwr_states(end_pwrlvl, state_info);
445 }
446 
447 /******************************************************************************
448  * This function validates a suspend request by making sure that if a standby
449  * state is requested then no power level is turned off and the highest power
450  * level is placed in a standby/retention state.
451  *
452  * It also ensures that the state level X will enter is not shallower than the
453  * state level X + 1 will enter.
454  *
455  * This validation will be enabled only for DEBUG builds as the platform is
456  * expected to perform these validations as well.
457  *****************************************************************************/
458 int psci_validate_suspend_req(const psci_power_state_t *state_info,
459 			      unsigned int is_power_down_state)
460 {
461 	unsigned int max_off_lvl, target_lvl, max_retn_lvl;
462 	plat_local_state_t state;
463 	plat_local_state_type_t req_state_type, deepest_state_type;
464 	int i;
465 
466 	/* Find the target suspend power level */
467 	target_lvl = psci_find_target_suspend_lvl(state_info);
468 	if (target_lvl == PSCI_INVALID_PWR_LVL)
469 		return PSCI_E_INVALID_PARAMS;
470 
471 	/* All power domain levels are in a RUN state to begin with */
472 	deepest_state_type = STATE_TYPE_RUN;
473 
474 	for (i = target_lvl; i >= PSCI_CPU_PWR_LVL; i--) {
475 		state = state_info->pwr_domain_state[i];
476 		req_state_type = find_local_state_type(state);
477 
478 		/*
479 		 * While traversing from the highest power level to the lowest,
480 		 * the state requested for lower levels has to be the same or
481 		 * deeper i.e. equal to or greater than the state at the higher
482 		 * levels. If this condition is true, then the requested state
483 		 * becomes the deepest state encountered so far.
484 		 */
485 		if (req_state_type < deepest_state_type)
486 			return PSCI_E_INVALID_PARAMS;
487 		deepest_state_type = req_state_type;
488 	}
489 
490 	/* Find the highest off power level */
491 	max_off_lvl = psci_find_max_off_lvl(state_info);
492 
493 	/* The target_lvl is either equal to the max_off_lvl or max_retn_lvl */
494 	max_retn_lvl = PSCI_INVALID_PWR_LVL;
495 	if (target_lvl != max_off_lvl)
496 		max_retn_lvl = target_lvl;
497 
498 	/*
499 	 * If this is not a request for a power down state then max off level
500 	 * has to be invalid and max retention level has to be a valid power
501 	 * level.
502 	 */
503 	if (!is_power_down_state && (max_off_lvl != PSCI_INVALID_PWR_LVL ||
504 				    max_retn_lvl == PSCI_INVALID_PWR_LVL))
505 		return PSCI_E_INVALID_PARAMS;
506 
507 	return PSCI_E_SUCCESS;
508 }
509 
510 /******************************************************************************
511  * This function finds the highest power level which will be powered down
512  * amongst all the power levels specified in the 'state_info' structure
513  *****************************************************************************/
514 unsigned int psci_find_max_off_lvl(const psci_power_state_t *state_info)
515 {
516 	int i;
517 
518 	for (i = PLAT_MAX_PWR_LVL; i >= PSCI_CPU_PWR_LVL; i--) {
519 		if (is_local_state_off(state_info->pwr_domain_state[i]))
520 			return i;
521 	}
522 
523 	return PSCI_INVALID_PWR_LVL;
524 }
525 
526 /******************************************************************************
527  * This functions finds the level of the highest power domain which will be
528  * placed in a low power state during a suspend operation.
529  *****************************************************************************/
530 unsigned int psci_find_target_suspend_lvl(const psci_power_state_t *state_info)
531 {
532 	int i;
533 
534 	for (i = PLAT_MAX_PWR_LVL; i >= PSCI_CPU_PWR_LVL; i--) {
535 		if (!is_local_state_run(state_info->pwr_domain_state[i]))
536 			return i;
537 	}
538 
539 	return PSCI_INVALID_PWR_LVL;
540 }
541 
542 /*******************************************************************************
543  * This function is passed a cpu_index and the highest level in the topology
544  * tree that the operation should be applied to. It picks up locks in order of
545  * increasing power domain level in the range specified.
546  ******************************************************************************/
547 void psci_acquire_pwr_domain_locks(unsigned int end_pwrlvl,
548 				   unsigned int cpu_idx)
549 {
550 	unsigned int parent_idx = psci_cpu_pd_nodes[cpu_idx].parent_node;
551 	unsigned int level;
552 
553 	/* No locking required for level 0. Hence start locking from level 1 */
554 	for (level = PSCI_CPU_PWR_LVL + 1; level <= end_pwrlvl; level++) {
555 		psci_lock_get(&psci_non_cpu_pd_nodes[parent_idx]);
556 		parent_idx = psci_non_cpu_pd_nodes[parent_idx].parent_node;
557 	}
558 }
559 
560 /*******************************************************************************
561  * This function is passed a cpu_index and the highest level in the topology
562  * tree that the operation should be applied to. It releases the locks in order
563  * of decreasing power domain level in the range specified.
564  ******************************************************************************/
565 void psci_release_pwr_domain_locks(unsigned int end_pwrlvl,
566 				   unsigned int cpu_idx)
567 {
568 	unsigned int parent_idx, parent_nodes[PLAT_MAX_PWR_LVL] = {0};
569 	int level;
570 
571 	/* Get the parent nodes */
572 	psci_get_parent_pwr_domain_nodes(cpu_idx, end_pwrlvl, parent_nodes);
573 
574 	/* Unlock top down. No unlocking required for level 0. */
575 	for (level = end_pwrlvl; level >= PSCI_CPU_PWR_LVL + 1; level--) {
576 		parent_idx = parent_nodes[level - 1];
577 		psci_lock_release(&psci_non_cpu_pd_nodes[parent_idx]);
578 	}
579 }
580 
581 /*******************************************************************************
582  * Simple routine to determine whether a mpidr is valid or not.
583  ******************************************************************************/
584 int psci_validate_mpidr(u_register_t mpidr)
585 {
586 	if (plat_core_pos_by_mpidr(mpidr) < 0)
587 		return PSCI_E_INVALID_PARAMS;
588 
589 	return PSCI_E_SUCCESS;
590 }
591 
592 /*******************************************************************************
593  * This function determines the full entrypoint information for the requested
594  * PSCI entrypoint on power on/resume and returns it.
595  ******************************************************************************/
596 #ifdef AARCH32
597 static int psci_get_ns_ep_info(entry_point_info_t *ep,
598 			       uintptr_t entrypoint,
599 			       u_register_t context_id)
600 {
601 	u_register_t ep_attr;
602 	unsigned int aif, ee, mode;
603 	u_register_t scr = read_scr();
604 	u_register_t ns_sctlr, sctlr;
605 
606 	/* Switch to non secure state */
607 	write_scr(scr | SCR_NS_BIT);
608 	isb();
609 	ns_sctlr = read_sctlr();
610 
611 	sctlr = scr & SCR_HCE_BIT ? read_hsctlr() : ns_sctlr;
612 
613 	/* Return to original state */
614 	write_scr(scr);
615 	isb();
616 	ee = 0;
617 
618 	ep_attr = NON_SECURE | EP_ST_DISABLE;
619 	if (sctlr & SCTLR_EE_BIT) {
620 		ep_attr |= EP_EE_BIG;
621 		ee = 1;
622 	}
623 	SET_PARAM_HEAD(ep, PARAM_EP, VERSION_1, ep_attr);
624 
625 	ep->pc = entrypoint;
626 	zeromem(&ep->args, sizeof(ep->args));
627 	ep->args.arg0 = context_id;
628 
629 	mode = scr & SCR_HCE_BIT ? MODE32_hyp : MODE32_svc;
630 
631 	/*
632 	 * TODO: Choose async. exception bits if HYP mode is not
633 	 * implemented according to the values of SCR.{AW, FW} bits
634 	 */
635 	aif = SPSR_ABT_BIT | SPSR_IRQ_BIT | SPSR_FIQ_BIT;
636 
637 	ep->spsr = SPSR_MODE32(mode, entrypoint & 0x1, ee, aif);
638 
639 	return PSCI_E_SUCCESS;
640 }
641 
642 #else
643 static int psci_get_ns_ep_info(entry_point_info_t *ep,
644 			       uintptr_t entrypoint,
645 			       u_register_t context_id)
646 {
647 	u_register_t ep_attr, sctlr;
648 	unsigned int daif, ee, mode;
649 	u_register_t ns_scr_el3 = read_scr_el3();
650 	u_register_t ns_sctlr_el1 = read_sctlr_el1();
651 
652 	sctlr = ns_scr_el3 & SCR_HCE_BIT ? read_sctlr_el2() : ns_sctlr_el1;
653 	ee = 0;
654 
655 	ep_attr = NON_SECURE | EP_ST_DISABLE;
656 	if (sctlr & SCTLR_EE_BIT) {
657 		ep_attr |= EP_EE_BIG;
658 		ee = 1;
659 	}
660 	SET_PARAM_HEAD(ep, PARAM_EP, VERSION_1, ep_attr);
661 
662 	ep->pc = entrypoint;
663 	zeromem(&ep->args, sizeof(ep->args));
664 	ep->args.arg0 = context_id;
665 
666 	/*
667 	 * Figure out whether the cpu enters the non-secure address space
668 	 * in aarch32 or aarch64
669 	 */
670 	if (ns_scr_el3 & SCR_RW_BIT) {
671 
672 		/*
673 		 * Check whether a Thumb entry point has been provided for an
674 		 * aarch64 EL
675 		 */
676 		if (entrypoint & 0x1)
677 			return PSCI_E_INVALID_ADDRESS;
678 
679 		mode = ns_scr_el3 & SCR_HCE_BIT ? MODE_EL2 : MODE_EL1;
680 
681 		ep->spsr = SPSR_64(mode, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
682 	} else {
683 
684 		mode = ns_scr_el3 & SCR_HCE_BIT ? MODE32_hyp : MODE32_svc;
685 
686 		/*
687 		 * TODO: Choose async. exception bits if HYP mode is not
688 		 * implemented according to the values of SCR.{AW, FW} bits
689 		 */
690 		daif = DAIF_ABT_BIT | DAIF_IRQ_BIT | DAIF_FIQ_BIT;
691 
692 		ep->spsr = SPSR_MODE32(mode, entrypoint & 0x1, ee, daif);
693 	}
694 
695 	return PSCI_E_SUCCESS;
696 }
697 #endif
698 
699 /*******************************************************************************
700  * This function validates the entrypoint with the platform layer if the
701  * appropriate pm_ops hook is exported by the platform and returns the
702  * 'entry_point_info'.
703  ******************************************************************************/
704 int psci_validate_entry_point(entry_point_info_t *ep,
705 			      uintptr_t entrypoint,
706 			      u_register_t context_id)
707 {
708 	int rc;
709 
710 	/* Validate the entrypoint using platform psci_ops */
711 	if (psci_plat_pm_ops->validate_ns_entrypoint) {
712 		rc = psci_plat_pm_ops->validate_ns_entrypoint(entrypoint);
713 		if (rc != PSCI_E_SUCCESS)
714 			return PSCI_E_INVALID_ADDRESS;
715 	}
716 
717 	/*
718 	 * Verify and derive the re-entry information for
719 	 * the non-secure world from the non-secure state from
720 	 * where this call originated.
721 	 */
722 	rc = psci_get_ns_ep_info(ep, entrypoint, context_id);
723 	return rc;
724 }
725 
726 /*******************************************************************************
727  * Generic handler which is called when a cpu is physically powered on. It
728  * traverses the node information and finds the highest power level powered
729  * off and performs generic, architectural, platform setup and state management
730  * to power on that power level and power levels below it.
731  * e.g. For a cpu that's been powered on, it will call the platform specific
732  * code to enable the gic cpu interface and for a cluster it will enable
733  * coherency at the interconnect level in addition to gic cpu interface.
734  ******************************************************************************/
735 void psci_warmboot_entrypoint(void)
736 {
737 	unsigned int end_pwrlvl, cpu_idx = plat_my_core_pos();
738 	psci_power_state_t state_info = { {PSCI_LOCAL_STATE_RUN} };
739 
740 	/*
741 	 * Verify that we have been explicitly turned ON or resumed from
742 	 * suspend.
743 	 */
744 	if (psci_get_aff_info_state() == AFF_STATE_OFF) {
745 		ERROR("Unexpected affinity info state");
746 		panic();
747 	}
748 
749 	/*
750 	 * Get the maximum power domain level to traverse to after this cpu
751 	 * has been physically powered up.
752 	 */
753 	end_pwrlvl = get_power_on_target_pwrlvl();
754 
755 	/*
756 	 * This function acquires the lock corresponding to each power level so
757 	 * that by the time all locks are taken, the system topology is snapshot
758 	 * and state management can be done safely.
759 	 */
760 	psci_acquire_pwr_domain_locks(end_pwrlvl,
761 				      cpu_idx);
762 
763 #if ENABLE_PSCI_STAT
764 	plat_psci_stat_accounting_stop(&state_info);
765 #endif
766 
767 	psci_get_target_local_pwr_states(end_pwrlvl, &state_info);
768 
769 	/*
770 	 * This CPU could be resuming from suspend or it could have just been
771 	 * turned on. To distinguish between these 2 cases, we examine the
772 	 * affinity state of the CPU:
773 	 *  - If the affinity state is ON_PENDING then it has just been
774 	 *    turned on.
775 	 *  - Else it is resuming from suspend.
776 	 *
777 	 * Depending on the type of warm reset identified, choose the right set
778 	 * of power management handler and perform the generic, architecture
779 	 * and platform specific handling.
780 	 */
781 	if (psci_get_aff_info_state() == AFF_STATE_ON_PENDING)
782 		psci_cpu_on_finish(cpu_idx, &state_info);
783 	else
784 		psci_cpu_suspend_finish(cpu_idx, &state_info);
785 
786 	/*
787 	 * Set the requested and target state of this CPU and all the higher
788 	 * power domains which are ancestors of this CPU to run.
789 	 */
790 	psci_set_pwr_domains_to_run(end_pwrlvl);
791 
792 #if ENABLE_PSCI_STAT
793 	/*
794 	 * Update PSCI stats.
795 	 * Caches are off when writing stats data on the power down path.
796 	 * Since caches are now enabled, it's necessary to do cache
797 	 * maintenance before reading that same data.
798 	 */
799 	psci_stats_update_pwr_up(end_pwrlvl, &state_info);
800 #endif
801 
802 	/*
803 	 * This loop releases the lock corresponding to each power level
804 	 * in the reverse order to which they were acquired.
805 	 */
806 	psci_release_pwr_domain_locks(end_pwrlvl,
807 				      cpu_idx);
808 }
809 
810 /*******************************************************************************
811  * This function initializes the set of hooks that PSCI invokes as part of power
812  * management operation. The power management hooks are expected to be provided
813  * by the SPD, after it finishes all its initialization
814  ******************************************************************************/
815 void psci_register_spd_pm_hook(const spd_pm_ops_t *pm)
816 {
817 	assert(pm);
818 	psci_spd_pm = pm;
819 
820 	if (pm->svc_migrate)
821 		psci_caps |= define_psci_cap(PSCI_MIG_AARCH64);
822 
823 	if (pm->svc_migrate_info)
824 		psci_caps |= define_psci_cap(PSCI_MIG_INFO_UP_CPU_AARCH64)
825 				| define_psci_cap(PSCI_MIG_INFO_TYPE);
826 }
827 
828 /*******************************************************************************
829  * This function invokes the migrate info hook in the spd_pm_ops. It performs
830  * the necessary return value validation. If the Secure Payload is UP and
831  * migrate capable, it returns the mpidr of the CPU on which the Secure payload
832  * is resident through the mpidr parameter. Else the value of the parameter on
833  * return is undefined.
834  ******************************************************************************/
835 int psci_spd_migrate_info(u_register_t *mpidr)
836 {
837 	int rc;
838 
839 	if (!psci_spd_pm || !psci_spd_pm->svc_migrate_info)
840 		return PSCI_E_NOT_SUPPORTED;
841 
842 	rc = psci_spd_pm->svc_migrate_info(mpidr);
843 
844 	assert(rc == PSCI_TOS_UP_MIG_CAP || rc == PSCI_TOS_NOT_UP_MIG_CAP \
845 		|| rc == PSCI_TOS_NOT_PRESENT_MP || rc == PSCI_E_NOT_SUPPORTED);
846 
847 	return rc;
848 }
849 
850 
851 /*******************************************************************************
852  * This function prints the state of all power domains present in the
853  * system
854  ******************************************************************************/
855 void psci_print_power_domain_map(void)
856 {
857 #if LOG_LEVEL >= LOG_LEVEL_INFO
858 	unsigned int idx;
859 	plat_local_state_t state;
860 	plat_local_state_type_t state_type;
861 
862 	/* This array maps to the PSCI_STATE_X definitions in psci.h */
863 	static const char * const psci_state_type_str[] = {
864 		"ON",
865 		"RETENTION",
866 		"OFF",
867 	};
868 
869 	INFO("PSCI Power Domain Map:\n");
870 	for (idx = 0; idx < (PSCI_NUM_PWR_DOMAINS - PLATFORM_CORE_COUNT);
871 							idx++) {
872 		state_type = find_local_state_type(
873 				psci_non_cpu_pd_nodes[idx].local_state);
874 		INFO("  Domain Node : Level %u, parent_node %d,"
875 				" State %s (0x%x)\n",
876 				psci_non_cpu_pd_nodes[idx].level,
877 				psci_non_cpu_pd_nodes[idx].parent_node,
878 				psci_state_type_str[state_type],
879 				psci_non_cpu_pd_nodes[idx].local_state);
880 	}
881 
882 	for (idx = 0; idx < PLATFORM_CORE_COUNT; idx++) {
883 		state = psci_get_cpu_local_state_by_idx(idx);
884 		state_type = find_local_state_type(state);
885 		INFO("  CPU Node : MPID 0x%llx, parent_node %d,"
886 				" State %s (0x%x)\n",
887 				(unsigned long long)psci_cpu_pd_nodes[idx].mpidr,
888 				psci_cpu_pd_nodes[idx].parent_node,
889 				psci_state_type_str[state_type],
890 				psci_get_cpu_local_state_by_idx(idx));
891 	}
892 #endif
893 }
894 
895 /******************************************************************************
896  * Return whether any secondaries were powered up with CPU_ON call. A CPU that
897  * have ever been powered up would have set its MPDIR value to something other
898  * than PSCI_INVALID_MPIDR. Note that MPDIR isn't reset back to
899  * PSCI_INVALID_MPIDR when a CPU is powered down later, so the return value is
900  * meaningful only when called on the primary CPU during early boot.
901  *****************************************************************************/
902 int psci_secondaries_brought_up(void)
903 {
904 	unsigned int idx, n_valid = 0;
905 
906 	for (idx = 0; idx < ARRAY_SIZE(psci_cpu_pd_nodes); idx++) {
907 		if (psci_cpu_pd_nodes[idx].mpidr != PSCI_INVALID_MPIDR)
908 			n_valid++;
909 	}
910 
911 	assert(n_valid);
912 
913 	return (n_valid > 1);
914 }
915 
916 #if ENABLE_PLAT_COMPAT
917 /*******************************************************************************
918  * PSCI Compatibility helper function to return the 'power_state' parameter of
919  * the PSCI CPU SUSPEND request for the current CPU. Returns PSCI_INVALID_DATA
920  * if not invoked within CPU_SUSPEND for the current CPU.
921  ******************************************************************************/
922 int psci_get_suspend_powerstate(void)
923 {
924 	/* Sanity check to verify that CPU is within CPU_SUSPEND */
925 	if (psci_get_aff_info_state() == AFF_STATE_ON &&
926 		!is_local_state_run(psci_get_cpu_local_state()))
927 		return psci_power_state_compat[plat_my_core_pos()];
928 
929 	return PSCI_INVALID_DATA;
930 }
931 
932 /*******************************************************************************
933  * PSCI Compatibility helper function to return the state id of the current
934  * cpu encoded in the 'power_state' parameter. Returns PSCI_INVALID_DATA
935  * if not invoked within CPU_SUSPEND for the current CPU.
936  ******************************************************************************/
937 int psci_get_suspend_stateid(void)
938 {
939 	unsigned int power_state;
940 	power_state = psci_get_suspend_powerstate();
941 	if (power_state != PSCI_INVALID_DATA)
942 		return psci_get_pstate_id(power_state);
943 
944 	return PSCI_INVALID_DATA;
945 }
946 
947 /*******************************************************************************
948  * PSCI Compatibility helper function to return the state id encoded in the
949  * 'power_state' parameter of the CPU specified by 'mpidr'. Returns
950  * PSCI_INVALID_DATA if the CPU is not in CPU_SUSPEND.
951  ******************************************************************************/
952 int psci_get_suspend_stateid_by_mpidr(unsigned long mpidr)
953 {
954 	int cpu_idx = plat_core_pos_by_mpidr(mpidr);
955 
956 	if (cpu_idx == -1)
957 		return PSCI_INVALID_DATA;
958 
959 	/* Sanity check to verify that the CPU is in CPU_SUSPEND */
960 	if (psci_get_aff_info_state_by_idx(cpu_idx) == AFF_STATE_ON &&
961 		!is_local_state_run(psci_get_cpu_local_state_by_idx(cpu_idx)))
962 		return psci_get_pstate_id(psci_power_state_compat[cpu_idx]);
963 
964 	return PSCI_INVALID_DATA;
965 }
966 
967 /*******************************************************************************
968  * This function returns highest affinity level which is in OFF
969  * state. The affinity instance with which the level is associated is
970  * determined by the caller.
971  ******************************************************************************/
972 unsigned int psci_get_max_phys_off_afflvl(void)
973 {
974 	psci_power_state_t state_info;
975 
976 	zeromem(&state_info, sizeof(state_info));
977 	psci_get_target_local_pwr_states(PLAT_MAX_PWR_LVL, &state_info);
978 
979 	return psci_find_target_suspend_lvl(&state_info);
980 }
981 
982 /*******************************************************************************
983  * PSCI Compatibility helper function to return target affinity level requested
984  * for the CPU_SUSPEND. This function assumes affinity levels correspond to
985  * power domain levels on the platform.
986  ******************************************************************************/
987 int psci_get_suspend_afflvl(void)
988 {
989 	return psci_get_suspend_pwrlvl();
990 }
991 
992 #endif
993 
994 /*******************************************************************************
995  * Initiate power down sequence, by calling power down operations registered for
996  * this CPU.
997  ******************************************************************************/
998 void psci_do_pwrdown_sequence(unsigned int power_level)
999 {
1000 #if HW_ASSISTED_COHERENCY
1001 	/*
1002 	 * With hardware-assisted coherency, the CPU drivers only initiate the
1003 	 * power down sequence, without performing cache-maintenance operations
1004 	 * in software. Data caches and MMU remain enabled both before and after
1005 	 * this call.
1006 	 */
1007 	prepare_cpu_pwr_dwn(power_level);
1008 #else
1009 	/*
1010 	 * Without hardware-assisted coherency, the CPU drivers disable data
1011 	 * caches and MMU, then perform cache-maintenance operations in
1012 	 * software.
1013 	 *
1014 	 * We ought to call prepare_cpu_pwr_dwn() to initiate power down
1015 	 * sequence. We currently have data caches and MMU enabled, but the
1016 	 * function will return with data caches and MMU disabled. We must
1017 	 * ensure that the stack memory is flushed out to memory before we start
1018 	 * popping from it again.
1019 	 */
1020 	psci_do_pwrdown_cache_maintenance(power_level);
1021 #endif
1022 }
1023