1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2012, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/acpi.h>
7 #include <linux/types.h>
8 #include <linux/err.h>
9 #include <linux/slab.h>
10 #include <linux/clk.h>
11 #include <linux/of.h>
12 #include <linux/of_address.h>
13 #include <linux/of_graph.h>
14 #include <linux/of_platform.h>
15 #include <linux/platform_device.h>
16 #include <linux/amba/bus.h>
17 #include <linux/coresight.h>
18 #include <linux/cpumask.h>
19 #include <asm/smp_plat.h>
20 
21 #include "coresight-priv.h"
22 /*
23  * coresight_alloc_conns: Allocate connections record for each output
24  * port from the device.
25  */
26 static int coresight_alloc_conns(struct device *dev,
27 				 struct coresight_platform_data *pdata)
28 {
29 	if (pdata->nr_outport) {
30 		pdata->conns = devm_kzalloc(dev, pdata->nr_outport *
31 					    sizeof(*pdata->conns),
32 					    GFP_KERNEL);
33 		if (!pdata->conns)
34 			return -ENOMEM;
35 	}
36 
37 	return 0;
38 }
39 
40 int coresight_device_fwnode_match(struct device *dev, const void *fwnode)
41 {
42 	return dev_fwnode(dev) == fwnode;
43 }
44 
45 static struct device *
46 coresight_find_device_by_fwnode(struct fwnode_handle *fwnode)
47 {
48 	struct device *dev = NULL;
49 
50 	/*
51 	 * If we have a non-configurable replicator, it will be found on the
52 	 * platform bus.
53 	 */
54 	dev = bus_find_device(&platform_bus_type, NULL,
55 			      fwnode, coresight_device_fwnode_match);
56 	if (dev)
57 		return dev;
58 
59 	/*
60 	 * We have a configurable component - circle through the AMBA bus
61 	 * looking for the device that matches the endpoint node.
62 	 */
63 	return bus_find_device(&amba_bustype, NULL,
64 			       fwnode, coresight_device_fwnode_match);
65 }
66 
67 #ifdef CONFIG_OF
68 static inline bool of_coresight_legacy_ep_is_input(struct device_node *ep)
69 {
70 	return of_property_read_bool(ep, "slave-mode");
71 }
72 
73 static void of_coresight_get_ports_legacy(const struct device_node *node,
74 					  int *nr_inport, int *nr_outport)
75 {
76 	struct device_node *ep = NULL;
77 	int in = 0, out = 0;
78 
79 	do {
80 		ep = of_graph_get_next_endpoint(node, ep);
81 		if (!ep)
82 			break;
83 
84 		if (of_coresight_legacy_ep_is_input(ep))
85 			in++;
86 		else
87 			out++;
88 
89 	} while (ep);
90 
91 	*nr_inport = in;
92 	*nr_outport = out;
93 }
94 
95 static struct device_node *of_coresight_get_port_parent(struct device_node *ep)
96 {
97 	struct device_node *parent = of_graph_get_port_parent(ep);
98 
99 	/*
100 	 * Skip one-level up to the real device node, if we
101 	 * are using the new bindings.
102 	 */
103 	if (of_node_name_eq(parent, "in-ports") ||
104 	    of_node_name_eq(parent, "out-ports"))
105 		parent = of_get_next_parent(parent);
106 
107 	return parent;
108 }
109 
110 static inline struct device_node *
111 of_coresight_get_input_ports_node(const struct device_node *node)
112 {
113 	return of_get_child_by_name(node, "in-ports");
114 }
115 
116 static inline struct device_node *
117 of_coresight_get_output_ports_node(const struct device_node *node)
118 {
119 	return of_get_child_by_name(node, "out-ports");
120 }
121 
122 static inline int
123 of_coresight_count_ports(struct device_node *port_parent)
124 {
125 	int i = 0;
126 	struct device_node *ep = NULL;
127 
128 	while ((ep = of_graph_get_next_endpoint(port_parent, ep)))
129 		i++;
130 	return i;
131 }
132 
133 static void of_coresight_get_ports(const struct device_node *node,
134 				   int *nr_inport, int *nr_outport)
135 {
136 	struct device_node *input_ports = NULL, *output_ports = NULL;
137 
138 	input_ports = of_coresight_get_input_ports_node(node);
139 	output_ports = of_coresight_get_output_ports_node(node);
140 
141 	if (input_ports || output_ports) {
142 		if (input_ports) {
143 			*nr_inport = of_coresight_count_ports(input_ports);
144 			of_node_put(input_ports);
145 		}
146 		if (output_ports) {
147 			*nr_outport = of_coresight_count_ports(output_ports);
148 			of_node_put(output_ports);
149 		}
150 	} else {
151 		/* Fall back to legacy DT bindings parsing */
152 		of_coresight_get_ports_legacy(node, nr_inport, nr_outport);
153 	}
154 }
155 
156 static int of_coresight_get_cpu(struct device *dev)
157 {
158 	int cpu;
159 	struct device_node *dn;
160 
161 	if (!dev->of_node)
162 		return -ENODEV;
163 
164 	dn = of_parse_phandle(dev->of_node, "cpu", 0);
165 	if (!dn)
166 		return -ENODEV;
167 
168 	cpu = of_cpu_node_to_id(dn);
169 	of_node_put(dn);
170 
171 	return cpu;
172 }
173 
174 /*
175  * of_coresight_parse_endpoint : Parse the given output endpoint @ep
176  * and fill the connection information in @conn
177  *
178  * Parses the local port, remote device name and the remote port.
179  *
180  * Returns :
181  *	 1	- If the parsing is successful and a connection record
182  *		  was created for an output connection.
183  *	 0	- If the parsing completed without any fatal errors.
184  *	-Errno	- Fatal error, abort the scanning.
185  */
186 static int of_coresight_parse_endpoint(struct device *dev,
187 				       struct device_node *ep,
188 				       struct coresight_connection *conn)
189 {
190 	int ret = 0;
191 	struct of_endpoint endpoint, rendpoint;
192 	struct device_node *rparent = NULL;
193 	struct device_node *rep = NULL;
194 	struct device *rdev = NULL;
195 	struct fwnode_handle *rdev_fwnode;
196 
197 	do {
198 		/* Parse the local port details */
199 		if (of_graph_parse_endpoint(ep, &endpoint))
200 			break;
201 		/*
202 		 * Get a handle on the remote endpoint and the device it is
203 		 * attached to.
204 		 */
205 		rep = of_graph_get_remote_endpoint(ep);
206 		if (!rep)
207 			break;
208 		rparent = of_coresight_get_port_parent(rep);
209 		if (!rparent)
210 			break;
211 		if (of_graph_parse_endpoint(rep, &rendpoint))
212 			break;
213 
214 		rdev_fwnode = of_fwnode_handle(rparent);
215 		/* If the remote device is not available, defer probing */
216 		rdev = coresight_find_device_by_fwnode(rdev_fwnode);
217 		if (!rdev) {
218 			ret = -EPROBE_DEFER;
219 			break;
220 		}
221 
222 		conn->outport = endpoint.port;
223 		/*
224 		 * Hold the refcount to the target device. This could be
225 		 * released via:
226 		 * 1) coresight_release_platform_data() if the probe fails or
227 		 *    this device is unregistered.
228 		 * 2) While removing the target device via
229 		 *    coresight_remove_match()
230 		 */
231 		conn->child_fwnode = fwnode_handle_get(rdev_fwnode);
232 		conn->child_port = rendpoint.port;
233 		/* Connection record updated */
234 		ret = 1;
235 	} while (0);
236 
237 	of_node_put(rparent);
238 	of_node_put(rep);
239 	put_device(rdev);
240 
241 	return ret;
242 }
243 
244 static int of_get_coresight_platform_data(struct device *dev,
245 					  struct coresight_platform_data *pdata)
246 {
247 	int ret = 0;
248 	struct coresight_connection *conn;
249 	struct device_node *ep = NULL;
250 	const struct device_node *parent = NULL;
251 	bool legacy_binding = false;
252 	struct device_node *node = dev->of_node;
253 
254 	/* Get the number of input and output port for this component */
255 	of_coresight_get_ports(node, &pdata->nr_inport, &pdata->nr_outport);
256 
257 	/* If there are no output connections, we are done */
258 	if (!pdata->nr_outport)
259 		return 0;
260 
261 	ret = coresight_alloc_conns(dev, pdata);
262 	if (ret)
263 		return ret;
264 
265 	parent = of_coresight_get_output_ports_node(node);
266 	/*
267 	 * If the DT uses obsoleted bindings, the ports are listed
268 	 * under the device and we need to filter out the input
269 	 * ports.
270 	 */
271 	if (!parent) {
272 		legacy_binding = true;
273 		parent = node;
274 		dev_warn_once(dev, "Uses obsolete Coresight DT bindings\n");
275 	}
276 
277 	conn = pdata->conns;
278 
279 	/* Iterate through each output port to discover topology */
280 	while ((ep = of_graph_get_next_endpoint(parent, ep))) {
281 		/*
282 		 * Legacy binding mixes input/output ports under the
283 		 * same parent. So, skip the input ports if we are dealing
284 		 * with legacy binding, as they processed with their
285 		 * connected output ports.
286 		 */
287 		if (legacy_binding && of_coresight_legacy_ep_is_input(ep))
288 			continue;
289 
290 		ret = of_coresight_parse_endpoint(dev, ep, conn);
291 		switch (ret) {
292 		case 1:
293 			conn++;		/* Fall through */
294 		case 0:
295 			break;
296 		default:
297 			return ret;
298 		}
299 	}
300 
301 	return 0;
302 }
303 #else
304 static inline int
305 of_get_coresight_platform_data(struct device *dev,
306 			       struct coresight_platform_data *pdata)
307 {
308 	return -ENOENT;
309 }
310 
311 static inline int of_coresight_get_cpu(struct device *dev)
312 {
313 	return -ENODEV;
314 }
315 #endif
316 
317 #ifdef CONFIG_ACPI
318 
319 #include <acpi/actypes.h>
320 #include <acpi/processor.h>
321 
322 /* ACPI Graph _DSD UUID : "ab02a46b-74c7-45a2-bd68-f7d344ef2153" */
323 static const guid_t acpi_graph_uuid = GUID_INIT(0xab02a46b, 0x74c7, 0x45a2,
324 						0xbd, 0x68, 0xf7, 0xd3,
325 						0x44, 0xef, 0x21, 0x53);
326 /* Coresight ACPI Graph UUID : "3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd" */
327 static const guid_t coresight_graph_uuid = GUID_INIT(0x3ecbc8b6, 0x1d0e, 0x4fb3,
328 						     0x81, 0x07, 0xe6, 0x27,
329 						     0xf8, 0x05, 0xc6, 0xcd);
330 #define ACPI_CORESIGHT_LINK_SLAVE	0
331 #define ACPI_CORESIGHT_LINK_MASTER	1
332 
333 static inline bool is_acpi_guid(const union acpi_object *obj)
334 {
335 	return (obj->type == ACPI_TYPE_BUFFER) && (obj->buffer.length == 16);
336 }
337 
338 /*
339  * acpi_guid_matches	- Checks if the given object is a GUID object and
340  * that it matches the supplied the GUID.
341  */
342 static inline bool acpi_guid_matches(const union acpi_object *obj,
343 				   const guid_t *guid)
344 {
345 	return is_acpi_guid(obj) &&
346 	       guid_equal((guid_t *)obj->buffer.pointer, guid);
347 }
348 
349 static inline bool is_acpi_dsd_graph_guid(const union acpi_object *obj)
350 {
351 	return acpi_guid_matches(obj, &acpi_graph_uuid);
352 }
353 
354 static inline bool is_acpi_coresight_graph_guid(const union acpi_object *obj)
355 {
356 	return acpi_guid_matches(obj, &coresight_graph_uuid);
357 }
358 
359 static inline bool is_acpi_coresight_graph(const union acpi_object *obj)
360 {
361 	const union acpi_object *graphid, *guid, *links;
362 
363 	if (obj->type != ACPI_TYPE_PACKAGE ||
364 	    obj->package.count < 3)
365 		return false;
366 
367 	graphid = &obj->package.elements[0];
368 	guid = &obj->package.elements[1];
369 	links = &obj->package.elements[2];
370 
371 	if (graphid->type != ACPI_TYPE_INTEGER ||
372 	    links->type != ACPI_TYPE_INTEGER)
373 		return false;
374 
375 	return is_acpi_coresight_graph_guid(guid);
376 }
377 
378 /*
379  * acpi_validate_dsd_graph	- Make sure the given _DSD graph conforms
380  * to the ACPI _DSD Graph specification.
381  *
382  * ACPI Devices Graph property has the following format:
383  *  {
384  *	Revision	- Integer, must be 0
385  *	NumberOfGraphs	- Integer, N indicating the following list.
386  *	Graph[1],
387  *	 ...
388  *	Graph[N]
389  *  }
390  *
391  * And each Graph entry has the following format:
392  *  {
393  *	GraphID		- Integer, identifying a graph the device belongs to.
394  *	UUID		- UUID identifying the specification that governs
395  *			  this graph. (e.g, see is_acpi_coresight_graph())
396  *	NumberOfLinks	- Number "N" of connections on this node of the graph.
397  *	Links[1]
398  *	...
399  *	Links[N]
400  *  }
401  *
402  * Where each "Links" entry has the following format:
403  *
404  * {
405  *	SourcePortAddress	- Integer
406  *	DestinationPortAddress	- Integer
407  *	DestinationDeviceName	- Reference to another device
408  *	( --- CoreSight specific extensions below ---)
409  *	DirectionOfFlow		- Integer 1 for output(master)
410  *				  0 for input(slave)
411  * }
412  *
413  * e.g:
414  * For a Funnel device
415  *
416  * Device(MFUN) {
417  *   ...
418  *
419  *   Name (_DSD, Package() {
420  *	// DSD Package contains tuples of {  Proeprty_Type_UUID, Package() }
421  *	ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), //Std. Property UUID
422  *	Package() {
423  *		Package(2) { "property-name", <property-value> }
424  *	},
425  *
426  *	ToUUID("ab02a46b-74c7-45a2-bd68-f7d344ef2153"), // ACPI Graph UUID
427  *	Package() {
428  *	  0,		// Revision
429  *	  1,		// NumberOfGraphs.
430  *	  Package() {	// Graph[0] Package
431  *	     1,		// GraphID
432  *	     // Coresight Graph UUID
433  *	     ToUUID("3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd"),
434  *	     3,		// NumberOfLinks aka ports
435  *	     // Link[0]: Output_0 -> Replicator:Input_0
436  *	     Package () { 0, 0, \_SB_.RPL0, 1 },
437  *	     // Link[1]: Input_0 <- Cluster0_Funnel0:Output_0
438  *	     Package () { 0, 0, \_SB_.CLU0.FUN0, 0 },
439  *	     // Link[2]: Input_1 <- Cluster1_Funnel0:Output_0
440  *	      Package () { 1, 0, \_SB_.CLU1.FUN0, 0 },
441  *	  }	// End of Graph[0] Package
442  *
443  *	}, // End of ACPI Graph Property
444  *  })
445  */
446 static inline bool acpi_validate_dsd_graph(const union acpi_object *graph)
447 {
448 	int i, n;
449 	const union acpi_object *rev, *nr_graphs;
450 
451 	/* The graph must contain at least the Revision and Number of Graphs */
452 	if (graph->package.count < 2)
453 		return false;
454 
455 	rev = &graph->package.elements[0];
456 	nr_graphs = &graph->package.elements[1];
457 
458 	if (rev->type != ACPI_TYPE_INTEGER ||
459 	    nr_graphs->type != ACPI_TYPE_INTEGER)
460 		return false;
461 
462 	/* We only support revision 0 */
463 	if (rev->integer.value != 0)
464 		return false;
465 
466 	n = nr_graphs->integer.value;
467 	/* CoreSight devices are only part of a single Graph */
468 	if (n != 1)
469 		return false;
470 
471 	/* Make sure the ACPI graph package has right number of elements */
472 	if (graph->package.count != (n + 2))
473 		return false;
474 
475 	/*
476 	 * Each entry must be a graph package with at least 3 members :
477 	 * { GraphID, UUID, NumberOfLinks(n), Links[.],... }
478 	 */
479 	for (i = 2; i < n + 2; i++) {
480 		const union acpi_object *obj = &graph->package.elements[i];
481 
482 		if (obj->type != ACPI_TYPE_PACKAGE ||
483 		    obj->package.count < 3)
484 			return false;
485 	}
486 
487 	return true;
488 }
489 
490 /* acpi_get_dsd_graph	- Find the _DSD Graph property for the given device. */
491 const union acpi_object *
492 acpi_get_dsd_graph(struct acpi_device *adev)
493 {
494 	int i;
495 	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
496 	acpi_status status;
497 	const union acpi_object *dsd;
498 
499 	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL,
500 					    &buf, ACPI_TYPE_PACKAGE);
501 	if (ACPI_FAILURE(status))
502 		return NULL;
503 
504 	dsd = buf.pointer;
505 
506 	/*
507 	 * _DSD property consists tuples { Prop_UUID, Package() }
508 	 * Iterate through all the packages and find the Graph.
509 	 */
510 	for (i = 0; i + 1 < dsd->package.count; i += 2) {
511 		const union acpi_object *guid, *package;
512 
513 		guid = &dsd->package.elements[i];
514 		package = &dsd->package.elements[i + 1];
515 
516 		/* All _DSD elements must have a UUID and a Package */
517 		if (!is_acpi_guid(guid) || package->type != ACPI_TYPE_PACKAGE)
518 			break;
519 		/* Skip the non-Graph _DSD packages */
520 		if (!is_acpi_dsd_graph_guid(guid))
521 			continue;
522 		if (acpi_validate_dsd_graph(package))
523 			return package;
524 		/* Invalid graph format, continue */
525 		dev_warn(&adev->dev, "Invalid Graph _DSD property\n");
526 	}
527 
528 	return NULL;
529 }
530 
531 static inline bool
532 acpi_validate_coresight_graph(const union acpi_object *cs_graph)
533 {
534 	int nlinks;
535 
536 	nlinks = cs_graph->package.elements[2].integer.value;
537 	/*
538 	 * Graph must have the following fields :
539 	 * { GraphID, GraphUUID, NumberOfLinks, Links... }
540 	 */
541 	if (cs_graph->package.count != (nlinks + 3))
542 		return false;
543 	/* The links are validated in acpi_coresight_parse_link() */
544 	return true;
545 }
546 
547 /*
548  * acpi_get_coresight_graph	- Parse the device _DSD tables and find
549  * the Graph property matching the CoreSight Graphs.
550  *
551  * Returns the pointer to the CoreSight Graph Package when found. Otherwise
552  * returns NULL.
553  */
554 const union acpi_object *
555 acpi_get_coresight_graph(struct acpi_device *adev)
556 {
557 	const union acpi_object *graph_list, *graph;
558 	int i, nr_graphs;
559 
560 	graph_list = acpi_get_dsd_graph(adev);
561 	if (!graph_list)
562 		return graph_list;
563 
564 	nr_graphs = graph_list->package.elements[1].integer.value;
565 
566 	for (i = 2; i < nr_graphs + 2; i++) {
567 		graph = &graph_list->package.elements[i];
568 		if (!is_acpi_coresight_graph(graph))
569 			continue;
570 		if (acpi_validate_coresight_graph(graph))
571 			return graph;
572 		/* Invalid graph format */
573 		break;
574 	}
575 
576 	return NULL;
577 }
578 
579 /*
580  * acpi_coresight_parse_link	- Parse the given Graph connection
581  * of the device and populate the coresight_connection for an output
582  * connection.
583  *
584  * CoreSight Graph specification mandates that the direction of the data
585  * flow must be specified in the link. i.e,
586  *
587  *	SourcePortAddress,	// Integer
588  *	DestinationPortAddress,	// Integer
589  *	DestinationDeviceName,	// Reference to another device
590  *	DirectionOfFlow,	// 1 for output(master), 0 for input(slave)
591  *
592  * Returns the direction of the data flow [ Input(slave) or Output(master) ]
593  * upon success.
594  * Returns an negative error number otherwise.
595  */
596 static int acpi_coresight_parse_link(struct acpi_device *adev,
597 				     const union acpi_object *link,
598 				     struct coresight_connection *conn)
599 {
600 	int rc, dir;
601 	const union acpi_object *fields;
602 	struct acpi_device *r_adev;
603 	struct device *rdev;
604 
605 	if (link->type != ACPI_TYPE_PACKAGE ||
606 	    link->package.count != 4)
607 		return -EINVAL;
608 
609 	fields = link->package.elements;
610 
611 	if (fields[0].type != ACPI_TYPE_INTEGER ||
612 	    fields[1].type != ACPI_TYPE_INTEGER ||
613 	    fields[2].type != ACPI_TYPE_LOCAL_REFERENCE ||
614 	    fields[3].type != ACPI_TYPE_INTEGER)
615 		return -EINVAL;
616 
617 	rc = acpi_bus_get_device(fields[2].reference.handle, &r_adev);
618 	if (rc)
619 		return rc;
620 
621 	dir = fields[3].integer.value;
622 	if (dir == ACPI_CORESIGHT_LINK_MASTER) {
623 		conn->outport = fields[0].integer.value;
624 		conn->child_port = fields[1].integer.value;
625 		rdev = coresight_find_device_by_fwnode(&r_adev->fwnode);
626 		if (!rdev)
627 			return -EPROBE_DEFER;
628 		/*
629 		 * Hold the refcount to the target device. This could be
630 		 * released via:
631 		 * 1) coresight_release_platform_data() if the probe fails or
632 		 *    this device is unregistered.
633 		 * 2) While removing the target device via
634 		 *    coresight_remove_match().
635 		 */
636 		conn->child_fwnode = fwnode_handle_get(&r_adev->fwnode);
637 	}
638 
639 	return dir;
640 }
641 
642 /*
643  * acpi_coresight_parse_graph	- Parse the _DSD CoreSight graph
644  * connection information and populate the supplied coresight_platform_data
645  * instance.
646  */
647 static int acpi_coresight_parse_graph(struct acpi_device *adev,
648 				      struct coresight_platform_data *pdata)
649 {
650 	int rc, i, nlinks;
651 	const union acpi_object *graph;
652 	struct coresight_connection *conns, *ptr;
653 
654 	pdata->nr_inport = pdata->nr_outport = 0;
655 	graph = acpi_get_coresight_graph(adev);
656 	if (!graph)
657 		return -ENOENT;
658 
659 	nlinks = graph->package.elements[2].integer.value;
660 	if (!nlinks)
661 		return 0;
662 
663 	/*
664 	 * To avoid scanning the table twice (once for finding the number of
665 	 * output links and then later for parsing the output links),
666 	 * cache the links information in one go and then later copy
667 	 * it to the pdata.
668 	 */
669 	conns = devm_kcalloc(&adev->dev, nlinks, sizeof(*conns), GFP_KERNEL);
670 	if (!conns)
671 		return -ENOMEM;
672 	ptr = conns;
673 	for (i = 0; i < nlinks; i++) {
674 		const union acpi_object *link = &graph->package.elements[3 + i];
675 		int dir;
676 
677 		dir = acpi_coresight_parse_link(adev, link, ptr);
678 		if (dir < 0)
679 			return dir;
680 
681 		if (dir == ACPI_CORESIGHT_LINK_MASTER) {
682 			pdata->nr_outport++;
683 			ptr++;
684 		} else {
685 			pdata->nr_inport++;
686 		}
687 	}
688 
689 	rc = coresight_alloc_conns(&adev->dev, pdata);
690 	if (rc)
691 		return rc;
692 
693 	/* Copy the connection information to the final location */
694 	for (i = 0; i < pdata->nr_outport; i++)
695 		pdata->conns[i] = conns[i];
696 
697 	devm_kfree(&adev->dev, conns);
698 	return 0;
699 }
700 
701 /*
702  * acpi_handle_to_logical_cpuid - Map a given acpi_handle to the
703  * logical CPU id of the corresponding CPU device.
704  *
705  * Returns the logical CPU id when found. Otherwise returns >= nr_cpus_id.
706  */
707 static int
708 acpi_handle_to_logical_cpuid(acpi_handle handle)
709 {
710 	int i;
711 	struct acpi_processor *pr;
712 
713 	for_each_possible_cpu(i) {
714 		pr = per_cpu(processors, i);
715 		if (pr && pr->handle == handle)
716 			break;
717 	}
718 
719 	return i;
720 }
721 
722 /*
723  * acpi_coresigh_get_cpu - Find the logical CPU id of the CPU associated
724  * with this coresight device. With ACPI bindings, the CoreSight components
725  * are listed as child device of the associated CPU.
726  *
727  * Returns the logical CPU id when found. Otherwise returns 0.
728  */
729 static int acpi_coresight_get_cpu(struct device *dev)
730 {
731 	int cpu;
732 	acpi_handle cpu_handle;
733 	acpi_status status;
734 	struct acpi_device *adev = ACPI_COMPANION(dev);
735 
736 	if (!adev)
737 		return -ENODEV;
738 	status = acpi_get_parent(adev->handle, &cpu_handle);
739 	if (ACPI_FAILURE(status))
740 		return -ENODEV;
741 
742 	cpu = acpi_handle_to_logical_cpuid(cpu_handle);
743 	if (cpu >= nr_cpu_ids)
744 		return -ENODEV;
745 	return cpu;
746 }
747 
748 static int
749 acpi_get_coresight_platform_data(struct device *dev,
750 				 struct coresight_platform_data *pdata)
751 {
752 	struct acpi_device *adev;
753 
754 	adev = ACPI_COMPANION(dev);
755 	if (!adev)
756 		return -EINVAL;
757 
758 	return acpi_coresight_parse_graph(adev, pdata);
759 }
760 
761 #else
762 
763 static inline int
764 acpi_get_coresight_platform_data(struct device *dev,
765 				 struct coresight_platform_data *pdata)
766 {
767 	return -ENOENT;
768 }
769 
770 static inline int acpi_coresight_get_cpu(struct device *dev)
771 {
772 	return -ENODEV;
773 }
774 #endif
775 
776 int coresight_get_cpu(struct device *dev)
777 {
778 	if (is_of_node(dev->fwnode))
779 		return of_coresight_get_cpu(dev);
780 	else if (is_acpi_device_node(dev->fwnode))
781 		return acpi_coresight_get_cpu(dev);
782 	return 0;
783 }
784 EXPORT_SYMBOL_GPL(coresight_get_cpu);
785 
786 struct coresight_platform_data *
787 coresight_get_platform_data(struct device *dev)
788 {
789 	int ret = -ENOENT;
790 	struct coresight_platform_data *pdata = NULL;
791 	struct fwnode_handle *fwnode = dev_fwnode(dev);
792 
793 	if (IS_ERR_OR_NULL(fwnode))
794 		goto error;
795 
796 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
797 	if (!pdata) {
798 		ret = -ENOMEM;
799 		goto error;
800 	}
801 
802 	if (is_of_node(fwnode))
803 		ret = of_get_coresight_platform_data(dev, pdata);
804 	else if (is_acpi_device_node(fwnode))
805 		ret = acpi_get_coresight_platform_data(dev, pdata);
806 
807 	if (!ret)
808 		return pdata;
809 error:
810 	if (!IS_ERR_OR_NULL(pdata))
811 		/* Cleanup the connection information */
812 		coresight_release_platform_data(pdata);
813 	return ERR_PTR(ret);
814 }
815 EXPORT_SYMBOL_GPL(coresight_get_platform_data);
816