xref: /linux/drivers/soc/xilinx/xlnx_event_manager.c (revision d6a5c562214f26e442c8ec3ff1e28e16675d1bcf)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Xilinx Event Management Driver
4  *
5  *  Copyright (C) 2021 Xilinx, Inc.
6  *
7  *  Abhyuday Godhasara <abhyuday.godhasara@xilinx.com>
8  */
9 
10 #include <linux/cpuhotplug.h>
11 #include <linux/firmware/xlnx-event-manager.h>
12 #include <linux/firmware/xlnx-zynqmp.h>
13 #include <linux/hashtable.h>
14 #include <linux/interrupt.h>
15 #include <linux/irq.h>
16 #include <linux/irqdomain.h>
17 #include <linux/module.h>
18 #include <linux/of_irq.h>
19 #include <linux/platform_device.h>
20 #include <linux/slab.h>
21 
22 static DEFINE_PER_CPU_READ_MOSTLY(int, cpu_number1);
23 
24 static int virq_sgi;
25 static int event_manager_availability = -EACCES;
26 
27 /* SGI number used for Event management driver */
28 #define XLNX_EVENT_SGI_NUM	(15)
29 
30 /* Max number of driver can register for same event */
31 #define MAX_DRIVER_PER_EVENT	(10U)
32 
33 /* Max HashMap Order for PM API feature check (1<<7 = 128) */
34 #define REGISTERED_DRIVER_MAX_ORDER	(7)
35 
36 #define MAX_BITS	(32U) /* Number of bits available for error mask */
37 
38 #define FIRMWARE_VERSION_MASK			(0xFFFFU)
39 #define REGISTER_NOTIFIER_FIRMWARE_VERSION	(2U)
40 
41 static DEFINE_HASHTABLE(reg_driver_map, REGISTERED_DRIVER_MAX_ORDER);
42 static int sgi_num = XLNX_EVENT_SGI_NUM;
43 
44 static bool is_need_to_unregister;
45 
46 /**
47  * struct agent_cb - Registered callback function and private data.
48  * @agent_data:		Data passed back to handler function.
49  * @eve_cb:		Function pointer to store the callback function.
50  * @list:		member to create list.
51  */
52 struct agent_cb {
53 	void *agent_data;
54 	event_cb_func_t eve_cb;
55 	struct list_head list;
56 };
57 
58 /**
59  * struct registered_event_data - Registered Event Data.
60  * @key:		key is the combine id(Node-Id | Event-Id) of type u64
61  *			where upper u32 for Node-Id and lower u32 for Event-Id,
62  *			And this used as key to index into hashmap.
63  * @cb_type:		Type of Api callback, like PM_NOTIFY_CB, etc.
64  * @wake:		If this flag set, firmware will wake up processor if is
65  *			in sleep or power down state.
66  * @cb_list_head:	Head of call back data list which contain the information
67  *			about registered handler and private data.
68  * @hentry:		hlist_node that hooks this entry into hashtable.
69  */
70 struct registered_event_data {
71 	u64 key;
72 	enum pm_api_cb_id cb_type;
73 	bool wake;
74 	struct list_head cb_list_head;
75 	struct hlist_node hentry;
76 };
77 
78 static bool xlnx_is_error_event(const u32 node_id)
79 {
80 	if (node_id == EVENT_ERROR_PMC_ERR1 ||
81 	    node_id == EVENT_ERROR_PMC_ERR2 ||
82 	    node_id == EVENT_ERROR_PSM_ERR1 ||
83 	    node_id == EVENT_ERROR_PSM_ERR2)
84 		return true;
85 
86 	return false;
87 }
88 
89 static int xlnx_add_cb_for_notify_event(const u32 node_id, const u32 event, const bool wake,
90 					event_cb_func_t cb_fun,	void *data)
91 {
92 	u64 key = 0;
93 	bool present_in_hash = false;
94 	struct registered_event_data *eve_data;
95 	struct agent_cb *cb_data;
96 	struct agent_cb *cb_pos;
97 	struct agent_cb *cb_next;
98 
99 	key = ((u64)node_id << 32U) | (u64)event;
100 	/* Check for existing entry in hash table for given key id */
101 	hash_for_each_possible(reg_driver_map, eve_data, hentry, key) {
102 		if (eve_data->key == key) {
103 			present_in_hash = true;
104 			break;
105 		}
106 	}
107 
108 	if (!present_in_hash) {
109 		/* Add new entry if not present in HASH table */
110 		eve_data = kmalloc(sizeof(*eve_data), GFP_KERNEL);
111 		if (!eve_data)
112 			return -ENOMEM;
113 		eve_data->key = key;
114 		eve_data->cb_type = PM_NOTIFY_CB;
115 		eve_data->wake = wake;
116 		INIT_LIST_HEAD(&eve_data->cb_list_head);
117 
118 		cb_data = kmalloc(sizeof(*cb_data), GFP_KERNEL);
119 		if (!cb_data)
120 			return -ENOMEM;
121 		cb_data->eve_cb = cb_fun;
122 		cb_data->agent_data = data;
123 
124 		/* Add into callback list */
125 		list_add(&cb_data->list, &eve_data->cb_list_head);
126 
127 		/* Add into HASH table */
128 		hash_add(reg_driver_map, &eve_data->hentry, key);
129 	} else {
130 		/* Search for callback function and private data in list */
131 		list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
132 			if (cb_pos->eve_cb == cb_fun &&
133 			    cb_pos->agent_data == data) {
134 				return 0;
135 			}
136 		}
137 
138 		/* Add multiple handler and private data in list */
139 		cb_data = kmalloc(sizeof(*cb_data), GFP_KERNEL);
140 		if (!cb_data)
141 			return -ENOMEM;
142 		cb_data->eve_cb = cb_fun;
143 		cb_data->agent_data = data;
144 
145 		list_add(&cb_data->list, &eve_data->cb_list_head);
146 	}
147 
148 	return 0;
149 }
150 
151 static int xlnx_add_cb_for_suspend(event_cb_func_t cb_fun, void *data)
152 {
153 	struct registered_event_data *eve_data;
154 	struct agent_cb *cb_data;
155 
156 	/* Check for existing entry in hash table for given cb_type */
157 	hash_for_each_possible(reg_driver_map, eve_data, hentry, PM_INIT_SUSPEND_CB) {
158 		if (eve_data->cb_type == PM_INIT_SUSPEND_CB) {
159 			pr_err("Found as already registered\n");
160 			return -EINVAL;
161 		}
162 	}
163 
164 	/* Add new entry if not present */
165 	eve_data = kmalloc(sizeof(*eve_data), GFP_KERNEL);
166 	if (!eve_data)
167 		return -ENOMEM;
168 
169 	eve_data->key = 0;
170 	eve_data->cb_type = PM_INIT_SUSPEND_CB;
171 	INIT_LIST_HEAD(&eve_data->cb_list_head);
172 
173 	cb_data = kmalloc(sizeof(*cb_data), GFP_KERNEL);
174 	if (!cb_data)
175 		return -ENOMEM;
176 	cb_data->eve_cb = cb_fun;
177 	cb_data->agent_data = data;
178 
179 	/* Add into callback list */
180 	list_add(&cb_data->list, &eve_data->cb_list_head);
181 
182 	hash_add(reg_driver_map, &eve_data->hentry, PM_INIT_SUSPEND_CB);
183 
184 	return 0;
185 }
186 
187 static int xlnx_remove_cb_for_suspend(event_cb_func_t cb_fun)
188 {
189 	bool is_callback_found = false;
190 	struct registered_event_data *eve_data;
191 	struct agent_cb *cb_pos;
192 	struct agent_cb *cb_next;
193 
194 	is_need_to_unregister = false;
195 
196 	/* Check for existing entry in hash table for given cb_type */
197 	hash_for_each_possible(reg_driver_map, eve_data, hentry, PM_INIT_SUSPEND_CB) {
198 		if (eve_data->cb_type == PM_INIT_SUSPEND_CB) {
199 			/* Delete the list of callback */
200 			list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
201 				if (cb_pos->eve_cb == cb_fun) {
202 					is_callback_found = true;
203 					list_del_init(&cb_pos->list);
204 					kfree(cb_pos);
205 				}
206 			}
207 			/* remove an object from a hashtable */
208 			hash_del(&eve_data->hentry);
209 			kfree(eve_data);
210 			is_need_to_unregister = true;
211 		}
212 	}
213 	if (!is_callback_found) {
214 		pr_warn("Didn't find any registered callback for suspend event\n");
215 		return -EINVAL;
216 	}
217 
218 	return 0;
219 }
220 
221 static int xlnx_remove_cb_for_notify_event(const u32 node_id, const u32 event,
222 					   event_cb_func_t cb_fun, void *data)
223 {
224 	bool is_callback_found = false;
225 	struct registered_event_data *eve_data;
226 	u64 key = ((u64)node_id << 32U) | (u64)event;
227 	struct agent_cb *cb_pos;
228 	struct agent_cb *cb_next;
229 
230 	is_need_to_unregister = false;
231 
232 	/* Check for existing entry in hash table for given key id */
233 	hash_for_each_possible(reg_driver_map, eve_data, hentry, key) {
234 		if (eve_data->key == key) {
235 			/* Delete the list of callback */
236 			list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
237 				if (cb_pos->eve_cb == cb_fun &&
238 				    cb_pos->agent_data == data) {
239 					is_callback_found = true;
240 					list_del_init(&cb_pos->list);
241 					kfree(cb_pos);
242 				}
243 			}
244 
245 			/* Remove HASH table if callback list is empty */
246 			if (list_empty(&eve_data->cb_list_head)) {
247 				/* remove an object from a HASH table */
248 				hash_del(&eve_data->hentry);
249 				kfree(eve_data);
250 				is_need_to_unregister = true;
251 			}
252 		}
253 	}
254 	if (!is_callback_found) {
255 		pr_warn("Didn't find any registered callback for 0x%x 0x%x\n",
256 			node_id, event);
257 		return -EINVAL;
258 	}
259 
260 	return 0;
261 }
262 
263 /**
264  * xlnx_register_event() - Register for the event.
265  * @cb_type:	Type of callback from pm_api_cb_id,
266  *			PM_NOTIFY_CB - for Error Events,
267  *			PM_INIT_SUSPEND_CB - for suspend callback.
268  * @node_id:	Node-Id related to event.
269  * @event:	Event Mask for the Error Event.
270  * @wake:	Flag specifying whether the subsystem should be woken upon
271  *		event notification.
272  * @cb_fun:	Function pointer to store the callback function.
273  * @data:	Pointer for the driver instance.
274  *
275  * Return:	Returns 0 on successful registration else error code.
276  */
277 int xlnx_register_event(const enum pm_api_cb_id cb_type, const u32 node_id, const u32 event,
278 			const bool wake, event_cb_func_t cb_fun, void *data)
279 {
280 	int ret = 0;
281 	u32 eve;
282 	int pos;
283 
284 	if (event_manager_availability)
285 		return event_manager_availability;
286 
287 	if (cb_type != PM_NOTIFY_CB && cb_type != PM_INIT_SUSPEND_CB) {
288 		pr_err("%s() Unsupported Callback 0x%x\n", __func__, cb_type);
289 		return -EINVAL;
290 	}
291 
292 	if (!cb_fun)
293 		return -EFAULT;
294 
295 	if (cb_type == PM_INIT_SUSPEND_CB) {
296 		ret = xlnx_add_cb_for_suspend(cb_fun, data);
297 	} else {
298 		if (!xlnx_is_error_event(node_id)) {
299 			/* Add entry for Node-Id/Event in hash table */
300 			ret = xlnx_add_cb_for_notify_event(node_id, event, wake, cb_fun, data);
301 		} else {
302 			/* Add into Hash table */
303 			for (pos = 0; pos < MAX_BITS; pos++) {
304 				eve = event & (1 << pos);
305 				if (!eve)
306 					continue;
307 
308 				/* Add entry for Node-Id/Eve in hash table */
309 				ret = xlnx_add_cb_for_notify_event(node_id, eve, wake, cb_fun,
310 								   data);
311 				/* Break the loop if got error */
312 				if (ret)
313 					break;
314 			}
315 			if (ret) {
316 				/* Skip the Event for which got the error */
317 				pos--;
318 				/* Remove registered(during this call) event from hash table */
319 				for ( ; pos >= 0; pos--) {
320 					eve = event & (1 << pos);
321 					if (!eve)
322 						continue;
323 					xlnx_remove_cb_for_notify_event(node_id, eve, cb_fun, data);
324 				}
325 			}
326 		}
327 
328 		if (ret) {
329 			pr_err("%s() failed for 0x%x and 0x%x: %d\r\n", __func__, node_id,
330 			       event, ret);
331 			return ret;
332 		}
333 
334 		/* Register for Node-Id/Event combination in firmware */
335 		ret = zynqmp_pm_register_notifier(node_id, event, wake, true);
336 		if (ret) {
337 			pr_err("%s() failed for 0x%x and 0x%x: %d\r\n", __func__, node_id,
338 			       event, ret);
339 			/* Remove already registered event from hash table */
340 			if (xlnx_is_error_event(node_id)) {
341 				for (pos = 0; pos < MAX_BITS; pos++) {
342 					eve = event & (1 << pos);
343 					if (!eve)
344 						continue;
345 					xlnx_remove_cb_for_notify_event(node_id, eve, cb_fun, data);
346 				}
347 			} else {
348 				xlnx_remove_cb_for_notify_event(node_id, event, cb_fun, data);
349 			}
350 			return ret;
351 		}
352 	}
353 
354 	return ret;
355 }
356 EXPORT_SYMBOL_GPL(xlnx_register_event);
357 
358 /**
359  * xlnx_unregister_event() - Unregister for the event.
360  * @cb_type:	Type of callback from pm_api_cb_id,
361  *			PM_NOTIFY_CB - for Error Events,
362  *			PM_INIT_SUSPEND_CB - for suspend callback.
363  * @node_id:	Node-Id related to event.
364  * @event:	Event Mask for the Error Event.
365  * @cb_fun:	Function pointer of callback function.
366  * @data:	Pointer of agent's private data.
367  *
368  * Return:	Returns 0 on successful unregistration else error code.
369  */
370 int xlnx_unregister_event(const enum pm_api_cb_id cb_type, const u32 node_id, const u32 event,
371 			  event_cb_func_t cb_fun, void *data)
372 {
373 	int ret = 0;
374 	u32 eve, pos;
375 
376 	is_need_to_unregister = false;
377 
378 	if (event_manager_availability)
379 		return event_manager_availability;
380 
381 	if (cb_type != PM_NOTIFY_CB && cb_type != PM_INIT_SUSPEND_CB) {
382 		pr_err("%s() Unsupported Callback 0x%x\n", __func__, cb_type);
383 		return -EINVAL;
384 	}
385 
386 	if (!cb_fun)
387 		return -EFAULT;
388 
389 	if (cb_type == PM_INIT_SUSPEND_CB) {
390 		ret = xlnx_remove_cb_for_suspend(cb_fun);
391 	} else {
392 		/* Remove Node-Id/Event from hash table */
393 		if (!xlnx_is_error_event(node_id)) {
394 			xlnx_remove_cb_for_notify_event(node_id, event, cb_fun, data);
395 		} else {
396 			for (pos = 0; pos < MAX_BITS; pos++) {
397 				eve = event & (1 << pos);
398 				if (!eve)
399 					continue;
400 
401 				xlnx_remove_cb_for_notify_event(node_id, eve, cb_fun, data);
402 			}
403 		}
404 
405 		/* Un-register if list is empty */
406 		if (is_need_to_unregister) {
407 			/* Un-register for Node-Id/Event combination */
408 			ret = zynqmp_pm_register_notifier(node_id, event, false, false);
409 			if (ret) {
410 				pr_err("%s() failed for 0x%x and 0x%x: %d\n",
411 				       __func__, node_id, event, ret);
412 				return ret;
413 			}
414 		}
415 	}
416 
417 	return ret;
418 }
419 EXPORT_SYMBOL_GPL(xlnx_unregister_event);
420 
421 static void xlnx_call_suspend_cb_handler(const u32 *payload)
422 {
423 	bool is_callback_found = false;
424 	struct registered_event_data *eve_data;
425 	u32 cb_type = payload[0];
426 	struct agent_cb *cb_pos;
427 	struct agent_cb *cb_next;
428 
429 	/* Check for existing entry in hash table for given cb_type */
430 	hash_for_each_possible(reg_driver_map, eve_data, hentry, cb_type) {
431 		if (eve_data->cb_type == cb_type) {
432 			list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
433 				cb_pos->eve_cb(&payload[0], cb_pos->agent_data);
434 				is_callback_found = true;
435 			}
436 		}
437 	}
438 	if (!is_callback_found)
439 		pr_warn("Didn't find any registered callback for suspend event\n");
440 }
441 
442 static void xlnx_call_notify_cb_handler(const u32 *payload)
443 {
444 	bool is_callback_found = false;
445 	struct registered_event_data *eve_data;
446 	u64 key = ((u64)payload[1] << 32U) | (u64)payload[2];
447 	int ret;
448 	struct agent_cb *cb_pos;
449 	struct agent_cb *cb_next;
450 
451 	/* Check for existing entry in hash table for given key id */
452 	hash_for_each_possible(reg_driver_map, eve_data, hentry, key) {
453 		if (eve_data->key == key) {
454 			list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
455 				cb_pos->eve_cb(&payload[0], cb_pos->agent_data);
456 				is_callback_found = true;
457 			}
458 
459 			/* re register with firmware to get future events */
460 			ret = zynqmp_pm_register_notifier(payload[1], payload[2],
461 							  eve_data->wake, true);
462 			if (ret) {
463 				pr_err("%s() failed for 0x%x and 0x%x: %d\r\n", __func__,
464 				       payload[1], payload[2], ret);
465 				list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head,
466 							 list) {
467 					/* Remove already registered event from hash table */
468 					xlnx_remove_cb_for_notify_event(payload[1], payload[2],
469 									cb_pos->eve_cb,
470 									cb_pos->agent_data);
471 				}
472 			}
473 		}
474 	}
475 	if (!is_callback_found)
476 		pr_warn("Didn't find any registered callback for 0x%x 0x%x\n",
477 			payload[1], payload[2]);
478 }
479 
480 static void xlnx_get_event_callback_data(u32 *buf)
481 {
482 	zynqmp_pm_invoke_fn(GET_CALLBACK_DATA, 0, 0, 0, 0, buf);
483 }
484 
485 static irqreturn_t xlnx_event_handler(int irq, void *dev_id)
486 {
487 	u32 cb_type, node_id, event, pos;
488 	u32 payload[CB_MAX_PAYLOAD_SIZE] = {0};
489 	u32 event_data[CB_MAX_PAYLOAD_SIZE] = {0};
490 
491 	/* Get event data */
492 	xlnx_get_event_callback_data(payload);
493 
494 	/* First element is callback type, others are callback arguments */
495 	cb_type = payload[0];
496 
497 	if (cb_type == PM_NOTIFY_CB) {
498 		node_id = payload[1];
499 		event = payload[2];
500 		if (!xlnx_is_error_event(node_id)) {
501 			xlnx_call_notify_cb_handler(payload);
502 		} else {
503 			/*
504 			 * Each call back function expecting payload as an input arguments.
505 			 * We can get multiple error events as in one call back through error
506 			 * mask. So payload[2] may can contain multiple error events.
507 			 * In reg_driver_map database we store data in the combination of single
508 			 * node_id-error combination.
509 			 * So coping the payload message into event_data and update the
510 			 * event_data[2] with Error Mask for single error event and use
511 			 * event_data as input argument for registered call back function.
512 			 *
513 			 */
514 			memcpy(event_data, payload, (4 * CB_MAX_PAYLOAD_SIZE));
515 			/* Support Multiple Error Event */
516 			for (pos = 0; pos < MAX_BITS; pos++) {
517 				if ((0 == (event & (1 << pos))))
518 					continue;
519 				event_data[2] = (event & (1 << pos));
520 				xlnx_call_notify_cb_handler(event_data);
521 			}
522 		}
523 	} else if (cb_type == PM_INIT_SUSPEND_CB) {
524 		xlnx_call_suspend_cb_handler(payload);
525 	} else {
526 		pr_err("%s() Unsupported Callback %d\n", __func__, cb_type);
527 	}
528 
529 	return IRQ_HANDLED;
530 }
531 
532 static int xlnx_event_cpuhp_start(unsigned int cpu)
533 {
534 	enable_percpu_irq(virq_sgi, IRQ_TYPE_NONE);
535 
536 	return 0;
537 }
538 
539 static int xlnx_event_cpuhp_down(unsigned int cpu)
540 {
541 	disable_percpu_irq(virq_sgi);
542 
543 	return 0;
544 }
545 
546 static void xlnx_disable_percpu_irq(void *data)
547 {
548 	disable_percpu_irq(virq_sgi);
549 }
550 
551 static int xlnx_event_init_sgi(struct platform_device *pdev)
552 {
553 	int ret = 0;
554 	int cpu = smp_processor_id();
555 	/*
556 	 * IRQ related structures are used for the following:
557 	 * for each SGI interrupt ensure its mapped by GIC IRQ domain
558 	 * and that each corresponding linux IRQ for the HW IRQ has
559 	 * a handler for when receiving an interrupt from the remote
560 	 * processor.
561 	 */
562 	struct irq_domain *domain;
563 	struct irq_fwspec sgi_fwspec;
564 	struct device_node *interrupt_parent = NULL;
565 	struct device *parent = pdev->dev.parent;
566 
567 	/* Find GIC controller to map SGIs. */
568 	interrupt_parent = of_irq_find_parent(parent->of_node);
569 	if (!interrupt_parent) {
570 		dev_err(&pdev->dev, "Failed to find property for Interrupt parent\n");
571 		return -EINVAL;
572 	}
573 
574 	/* Each SGI needs to be associated with GIC's IRQ domain. */
575 	domain = irq_find_host(interrupt_parent);
576 	of_node_put(interrupt_parent);
577 
578 	/* Each mapping needs GIC domain when finding IRQ mapping. */
579 	sgi_fwspec.fwnode = domain->fwnode;
580 
581 	/*
582 	 * When irq domain looks at mapping each arg is as follows:
583 	 * 3 args for: interrupt type (SGI), interrupt # (set later), type
584 	 */
585 	sgi_fwspec.param_count = 1;
586 
587 	/* Set SGI's hwirq */
588 	sgi_fwspec.param[0] = sgi_num;
589 	virq_sgi = irq_create_fwspec_mapping(&sgi_fwspec);
590 
591 	per_cpu(cpu_number1, cpu) = cpu;
592 	ret = request_percpu_irq(virq_sgi, xlnx_event_handler, "xlnx_event_mgmt",
593 				 &cpu_number1);
594 	WARN_ON(ret);
595 	if (ret) {
596 		irq_dispose_mapping(virq_sgi);
597 		return ret;
598 	}
599 
600 	irq_to_desc(virq_sgi);
601 	irq_set_status_flags(virq_sgi, IRQ_PER_CPU);
602 
603 	return ret;
604 }
605 
606 static void xlnx_event_cleanup_sgi(struct platform_device *pdev)
607 {
608 	int cpu = smp_processor_id();
609 
610 	per_cpu(cpu_number1, cpu) = cpu;
611 
612 	cpuhp_remove_state(CPUHP_AP_ONLINE_DYN);
613 
614 	on_each_cpu(xlnx_disable_percpu_irq, NULL, 1);
615 
616 	irq_clear_status_flags(virq_sgi, IRQ_PER_CPU);
617 	free_percpu_irq(virq_sgi, &cpu_number1);
618 	irq_dispose_mapping(virq_sgi);
619 }
620 
621 static int xlnx_event_manager_probe(struct platform_device *pdev)
622 {
623 	int ret;
624 
625 	ret = zynqmp_pm_feature(PM_REGISTER_NOTIFIER);
626 	if (ret < 0) {
627 		dev_err(&pdev->dev, "Feature check failed with %d\n", ret);
628 		return ret;
629 	}
630 
631 	if ((ret & FIRMWARE_VERSION_MASK) <
632 	    REGISTER_NOTIFIER_FIRMWARE_VERSION) {
633 		dev_err(&pdev->dev, "Register notifier version error. Expected Firmware: v%d - Found: v%d\n",
634 			REGISTER_NOTIFIER_FIRMWARE_VERSION,
635 			ret & FIRMWARE_VERSION_MASK);
636 		return -EOPNOTSUPP;
637 	}
638 
639 	/* Initialize the SGI */
640 	ret = xlnx_event_init_sgi(pdev);
641 	if (ret) {
642 		dev_err(&pdev->dev, "SGI Init has been failed with %d\n", ret);
643 		return ret;
644 	}
645 
646 	/* Setup function for the CPU hot-plug cases */
647 	cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "soc/event:starting",
648 			  xlnx_event_cpuhp_start, xlnx_event_cpuhp_down);
649 
650 	ret = zynqmp_pm_register_sgi(sgi_num, 0);
651 	if (ret) {
652 		dev_err(&pdev->dev, "SGI %d Registration over TF-A failed with %d\n", sgi_num, ret);
653 		xlnx_event_cleanup_sgi(pdev);
654 		return ret;
655 	}
656 
657 	event_manager_availability = 0;
658 
659 	dev_info(&pdev->dev, "SGI %d Registered over TF-A\n", sgi_num);
660 	dev_info(&pdev->dev, "Xilinx Event Management driver probed\n");
661 
662 	return ret;
663 }
664 
665 static int xlnx_event_manager_remove(struct platform_device *pdev)
666 {
667 	int i;
668 	struct registered_event_data *eve_data;
669 	struct hlist_node *tmp;
670 	int ret;
671 	struct agent_cb *cb_pos;
672 	struct agent_cb *cb_next;
673 
674 	hash_for_each_safe(reg_driver_map, i, tmp, eve_data, hentry) {
675 		list_for_each_entry_safe(cb_pos, cb_next, &eve_data->cb_list_head, list) {
676 			list_del_init(&cb_pos->list);
677 			kfree(cb_pos);
678 		}
679 		hash_del(&eve_data->hentry);
680 		kfree(eve_data);
681 	}
682 
683 	ret = zynqmp_pm_register_sgi(0, 1);
684 	if (ret)
685 		dev_err(&pdev->dev, "SGI unregistration over TF-A failed with %d\n", ret);
686 
687 	xlnx_event_cleanup_sgi(pdev);
688 
689 	event_manager_availability = -EACCES;
690 
691 	return ret;
692 }
693 
694 static struct platform_driver xlnx_event_manager_driver = {
695 	.probe = xlnx_event_manager_probe,
696 	.remove = xlnx_event_manager_remove,
697 	.driver = {
698 		.name = "xlnx_event_manager",
699 	},
700 };
701 module_param(sgi_num, uint, 0);
702 module_platform_driver(xlnx_event_manager_driver);
703