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_graph.h>
13#include <linux/platform_device.h>
14#include <linux/amba/bus.h>
15#include <linux/coresight.h>
16#include <linux/cpumask.h>
17#include <asm/smp_plat.h>
18
19#include "coresight-priv.h"
20
21/*
22 * Add an entry to the connection list and assign @conn's contents to it.
23 *
24 * If the output port is already assigned on this device, return -EINVAL
25 */
26struct coresight_connection *
27coresight_add_out_conn(struct device *dev,
28		       struct coresight_platform_data *pdata,
29		       const struct coresight_connection *new_conn)
30{
31	int i;
32	struct coresight_connection *conn;
33
34	/*
35	 * Warn on any existing duplicate output port.
36	 */
37	for (i = 0; i < pdata->nr_outconns; ++i) {
38		conn = pdata->out_conns[i];
39		/* Output == -1 means ignore the port for example for helpers */
40		if (conn->src_port != -1 &&
41		    conn->src_port == new_conn->src_port) {
42			dev_warn(dev, "Duplicate output port %d\n",
43				 conn->src_port);
44			return ERR_PTR(-EINVAL);
45		}
46	}
47
48	pdata->nr_outconns++;
49	pdata->out_conns =
50		devm_krealloc_array(dev, pdata->out_conns, pdata->nr_outconns,
51				    sizeof(*pdata->out_conns), GFP_KERNEL);
52	if (!pdata->out_conns)
53		return ERR_PTR(-ENOMEM);
54
55	conn = devm_kmalloc(dev, sizeof(struct coresight_connection),
56			    GFP_KERNEL);
57	if (!conn)
58		return ERR_PTR(-ENOMEM);
59
60	/*
61	 * Copy the new connection into the allocation, save the pointer to the
62	 * end of the connection array and also return it in case it needs to be
63	 * used right away.
64	 */
65	*conn = *new_conn;
66	pdata->out_conns[pdata->nr_outconns - 1] = conn;
67	return conn;
68}
69EXPORT_SYMBOL_GPL(coresight_add_out_conn);
70
71/*
72 * Add an input connection reference to @out_conn in the target's in_conns array
73 *
74 * @out_conn: Existing output connection to store as an input on the
75 *	      connection's remote device.
76 */
77int coresight_add_in_conn(struct coresight_connection *out_conn)
78{
79	int i;
80	struct device *dev = out_conn->dest_dev->dev.parent;
81	struct coresight_platform_data *pdata = out_conn->dest_dev->pdata;
82
83	for (i = 0; i < pdata->nr_inconns; ++i)
84		if (!pdata->in_conns[i]) {
85			pdata->in_conns[i] = out_conn;
86			return 0;
87		}
88
89	pdata->nr_inconns++;
90	pdata->in_conns =
91		devm_krealloc_array(dev, pdata->in_conns, pdata->nr_inconns,
92				    sizeof(*pdata->in_conns), GFP_KERNEL);
93	if (!pdata->in_conns)
94		return -ENOMEM;
95	pdata->in_conns[pdata->nr_inconns - 1] = out_conn;
96	return 0;
97}
98EXPORT_SYMBOL_GPL(coresight_add_in_conn);
99
100static struct device *
101coresight_find_device_by_fwnode(struct fwnode_handle *fwnode)
102{
103	struct device *dev = NULL;
104
105	/*
106	 * If we have a non-configurable replicator, it will be found on the
107	 * platform bus.
108	 */
109	dev = bus_find_device_by_fwnode(&platform_bus_type, fwnode);
110	if (dev)
111		return dev;
112
113	/*
114	 * We have a configurable component - circle through the AMBA bus
115	 * looking for the device that matches the endpoint node.
116	 */
117	return bus_find_device_by_fwnode(&amba_bustype, fwnode);
118}
119
120/*
121 * Find a registered coresight device from a device fwnode.
122 * The node info is associated with the AMBA parent, but the
123 * csdev keeps a copy so iterate round the coresight bus to
124 * find the device.
125 */
126struct coresight_device *
127coresight_find_csdev_by_fwnode(struct fwnode_handle *r_fwnode)
128{
129	struct device *dev;
130	struct coresight_device *csdev = NULL;
131
132	dev = bus_find_device_by_fwnode(&coresight_bustype, r_fwnode);
133	if (dev) {
134		csdev = to_coresight_device(dev);
135		put_device(dev);
136	}
137	return csdev;
138}
139EXPORT_SYMBOL_GPL(coresight_find_csdev_by_fwnode);
140
141#ifdef CONFIG_OF
142static inline bool of_coresight_legacy_ep_is_input(struct device_node *ep)
143{
144	return of_property_read_bool(ep, "slave-mode");
145}
146
147static struct device_node *of_coresight_get_port_parent(struct device_node *ep)
148{
149	struct device_node *parent = of_graph_get_port_parent(ep);
150
151	/*
152	 * Skip one-level up to the real device node, if we
153	 * are using the new bindings.
154	 */
155	if (of_node_name_eq(parent, "in-ports") ||
156	    of_node_name_eq(parent, "out-ports"))
157		parent = of_get_next_parent(parent);
158
159	return parent;
160}
161
162static inline struct device_node *
163of_coresight_get_output_ports_node(const struct device_node *node)
164{
165	return of_get_child_by_name(node, "out-ports");
166}
167
168static int of_coresight_get_cpu(struct device *dev)
169{
170	int cpu;
171	struct device_node *dn;
172
173	if (!dev->of_node)
174		return -ENODEV;
175
176	dn = of_parse_phandle(dev->of_node, "cpu", 0);
177	if (!dn)
178		return -ENODEV;
179
180	cpu = of_cpu_node_to_id(dn);
181	of_node_put(dn);
182
183	return cpu;
184}
185
186/*
187 * of_coresight_parse_endpoint : Parse the given output endpoint @ep
188 * and fill the connection information in @pdata->out_conns
189 *
190 * Parses the local port, remote device name and the remote port.
191 *
192 * Returns :
193 *	 0	- If the parsing completed without any fatal errors.
194 *	-Errno	- Fatal error, abort the scanning.
195 */
196static int of_coresight_parse_endpoint(struct device *dev,
197				       struct device_node *ep,
198				       struct coresight_platform_data *pdata)
199{
200	int ret = 0;
201	struct of_endpoint endpoint, rendpoint;
202	struct device_node *rparent = NULL;
203	struct device_node *rep = NULL;
204	struct device *rdev = NULL;
205	struct fwnode_handle *rdev_fwnode;
206	struct coresight_connection conn = {};
207	struct coresight_connection *new_conn;
208
209	do {
210		/* Parse the local port details */
211		if (of_graph_parse_endpoint(ep, &endpoint))
212			break;
213		/*
214		 * Get a handle on the remote endpoint and the device it is
215		 * attached to.
216		 */
217		rep = of_graph_get_remote_endpoint(ep);
218		if (!rep)
219			break;
220		rparent = of_coresight_get_port_parent(rep);
221		if (!rparent)
222			break;
223		if (of_graph_parse_endpoint(rep, &rendpoint))
224			break;
225
226		rdev_fwnode = of_fwnode_handle(rparent);
227		/* If the remote device is not available, defer probing */
228		rdev = coresight_find_device_by_fwnode(rdev_fwnode);
229		if (!rdev) {
230			ret = -EPROBE_DEFER;
231			break;
232		}
233
234		conn.src_port = endpoint.port;
235		/*
236		 * Hold the refcount to the target device. This could be
237		 * released via:
238		 * 1) coresight_release_platform_data() if the probe fails or
239		 *    this device is unregistered.
240		 * 2) While removing the target device via
241		 *    coresight_remove_match()
242		 */
243		conn.dest_fwnode = fwnode_handle_get(rdev_fwnode);
244		conn.dest_port = rendpoint.port;
245
246		new_conn = coresight_add_out_conn(dev, pdata, &conn);
247		if (IS_ERR_VALUE(new_conn)) {
248			fwnode_handle_put(conn.dest_fwnode);
249			return PTR_ERR(new_conn);
250		}
251		/* Connection record updated */
252	} while (0);
253
254	of_node_put(rparent);
255	of_node_put(rep);
256	put_device(rdev);
257
258	return ret;
259}
260
261static int of_get_coresight_platform_data(struct device *dev,
262					  struct coresight_platform_data *pdata)
263{
264	int ret = 0;
265	struct device_node *ep = NULL;
266	const struct device_node *parent = NULL;
267	bool legacy_binding = false;
268	struct device_node *node = dev->of_node;
269
270	parent = of_coresight_get_output_ports_node(node);
271	/*
272	 * If the DT uses obsoleted bindings, the ports are listed
273	 * under the device and we need to filter out the input
274	 * ports.
275	 */
276	if (!parent) {
277		/*
278		 * Avoid warnings in of_graph_get_next_endpoint()
279		 * if the device doesn't have any graph connections
280		 */
281		if (!of_graph_is_present(node))
282			return 0;
283		legacy_binding = true;
284		parent = node;
285		dev_warn_once(dev, "Uses obsolete Coresight DT bindings\n");
286	}
287
288	/* Iterate through each output port to discover topology */
289	while ((ep = of_graph_get_next_endpoint(parent, ep))) {
290		/*
291		 * Legacy binding mixes input/output ports under the
292		 * same parent. So, skip the input ports if we are dealing
293		 * with legacy binding, as they processed with their
294		 * connected output ports.
295		 */
296		if (legacy_binding && of_coresight_legacy_ep_is_input(ep))
297			continue;
298
299		ret = of_coresight_parse_endpoint(dev, ep, pdata);
300		if (ret)
301			return ret;
302	}
303
304	return 0;
305}
306#else
307static inline int
308of_get_coresight_platform_data(struct device *dev,
309			       struct coresight_platform_data *pdata)
310{
311	return -ENOENT;
312}
313
314static inline int of_coresight_get_cpu(struct device *dev)
315{
316	return -ENODEV;
317}
318#endif
319
320#ifdef CONFIG_ACPI
321
322#include <acpi/actypes.h>
323#include <acpi/processor.h>
324
325/* ACPI Graph _DSD UUID : "ab02a46b-74c7-45a2-bd68-f7d344ef2153" */
326static const guid_t acpi_graph_uuid = GUID_INIT(0xab02a46b, 0x74c7, 0x45a2,
327						0xbd, 0x68, 0xf7, 0xd3,
328						0x44, 0xef, 0x21, 0x53);
329/* Coresight ACPI Graph UUID : "3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd" */
330static const guid_t coresight_graph_uuid = GUID_INIT(0x3ecbc8b6, 0x1d0e, 0x4fb3,
331						     0x81, 0x07, 0xe6, 0x27,
332						     0xf8, 0x05, 0xc6, 0xcd);
333#define ACPI_CORESIGHT_LINK_SLAVE	0
334#define ACPI_CORESIGHT_LINK_MASTER	1
335
336static inline bool is_acpi_guid(const union acpi_object *obj)
337{
338	return (obj->type == ACPI_TYPE_BUFFER) && (obj->buffer.length == 16);
339}
340
341/*
342 * acpi_guid_matches	- Checks if the given object is a GUID object and
343 * that it matches the supplied the GUID.
344 */
345static inline bool acpi_guid_matches(const union acpi_object *obj,
346				   const guid_t *guid)
347{
348	return is_acpi_guid(obj) &&
349	       guid_equal((guid_t *)obj->buffer.pointer, guid);
350}
351
352static inline bool is_acpi_dsd_graph_guid(const union acpi_object *obj)
353{
354	return acpi_guid_matches(obj, &acpi_graph_uuid);
355}
356
357static inline bool is_acpi_coresight_graph_guid(const union acpi_object *obj)
358{
359	return acpi_guid_matches(obj, &coresight_graph_uuid);
360}
361
362static inline bool is_acpi_coresight_graph(const union acpi_object *obj)
363{
364	const union acpi_object *graphid, *guid, *links;
365
366	if (obj->type != ACPI_TYPE_PACKAGE ||
367	    obj->package.count < 3)
368		return false;
369
370	graphid = &obj->package.elements[0];
371	guid = &obj->package.elements[1];
372	links = &obj->package.elements[2];
373
374	if (graphid->type != ACPI_TYPE_INTEGER ||
375	    links->type != ACPI_TYPE_INTEGER)
376		return false;
377
378	return is_acpi_coresight_graph_guid(guid);
379}
380
381/*
382 * acpi_validate_dsd_graph	- Make sure the given _DSD graph conforms
383 * to the ACPI _DSD Graph specification.
384 *
385 * ACPI Devices Graph property has the following format:
386 *  {
387 *	Revision	- Integer, must be 0
388 *	NumberOfGraphs	- Integer, N indicating the following list.
389 *	Graph[1],
390 *	 ...
391 *	Graph[N]
392 *  }
393 *
394 * And each Graph entry has the following format:
395 *  {
396 *	GraphID		- Integer, identifying a graph the device belongs to.
397 *	UUID		- UUID identifying the specification that governs
398 *			  this graph. (e.g, see is_acpi_coresight_graph())
399 *	NumberOfLinks	- Number "N" of connections on this node of the graph.
400 *	Links[1]
401 *	...
402 *	Links[N]
403 *  }
404 *
405 * Where each "Links" entry has the following format:
406 *
407 * {
408 *	SourcePortAddress	- Integer
409 *	DestinationPortAddress	- Integer
410 *	DestinationDeviceName	- Reference to another device
411 *	( --- CoreSight specific extensions below ---)
412 *	DirectionOfFlow		- Integer 1 for output(master)
413 *				  0 for input(slave)
414 * }
415 *
416 * e.g:
417 * For a Funnel device
418 *
419 * Device(MFUN) {
420 *   ...
421 *
422 *   Name (_DSD, Package() {
423 *	// DSD Package contains tuples of {  Proeprty_Type_UUID, Package() }
424 *	ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), //Std. Property UUID
425 *	Package() {
426 *		Package(2) { "property-name", <property-value> }
427 *	},
428 *
429 *	ToUUID("ab02a46b-74c7-45a2-bd68-f7d344ef2153"), // ACPI Graph UUID
430 *	Package() {
431 *	  0,		// Revision
432 *	  1,		// NumberOfGraphs.
433 *	  Package() {	// Graph[0] Package
434 *	     1,		// GraphID
435 *	     // Coresight Graph UUID
436 *	     ToUUID("3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd"),
437 *	     3,		// NumberOfLinks aka ports
438 *	     // Link[0]: Output_0 -> Replicator:Input_0
439 *	     Package () { 0, 0, \_SB_.RPL0, 1 },
440 *	     // Link[1]: Input_0 <- Cluster0_Funnel0:Output_0
441 *	     Package () { 0, 0, \_SB_.CLU0.FUN0, 0 },
442 *	     // Link[2]: Input_1 <- Cluster1_Funnel0:Output_0
443 *	      Package () { 1, 0, \_SB_.CLU1.FUN0, 0 },
444 *	  }	// End of Graph[0] Package
445 *
446 *	}, // End of ACPI Graph Property
447 *  })
448 */
449static inline bool acpi_validate_dsd_graph(const union acpi_object *graph)
450{
451	int i, n;
452	const union acpi_object *rev, *nr_graphs;
453
454	/* The graph must contain at least the Revision and Number of Graphs */
455	if (graph->package.count < 2)
456		return false;
457
458	rev = &graph->package.elements[0];
459	nr_graphs = &graph->package.elements[1];
460
461	if (rev->type != ACPI_TYPE_INTEGER ||
462	    nr_graphs->type != ACPI_TYPE_INTEGER)
463		return false;
464
465	/* We only support revision 0 */
466	if (rev->integer.value != 0)
467		return false;
468
469	n = nr_graphs->integer.value;
470	/* CoreSight devices are only part of a single Graph */
471	if (n != 1)
472		return false;
473
474	/* Make sure the ACPI graph package has right number of elements */
475	if (graph->package.count != (n + 2))
476		return false;
477
478	/*
479	 * Each entry must be a graph package with at least 3 members :
480	 * { GraphID, UUID, NumberOfLinks(n), Links[.],... }
481	 */
482	for (i = 2; i < n + 2; i++) {
483		const union acpi_object *obj = &graph->package.elements[i];
484
485		if (obj->type != ACPI_TYPE_PACKAGE ||
486		    obj->package.count < 3)
487			return false;
488	}
489
490	return true;
491}
492
493/* acpi_get_dsd_graph	- Find the _DSD Graph property for the given device. */
494static const union acpi_object *
495acpi_get_dsd_graph(struct acpi_device *adev, struct acpi_buffer *buf)
496{
497	int i;
498	acpi_status status;
499	const union acpi_object *dsd;
500
501	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL,
502					    buf, ACPI_TYPE_PACKAGE);
503	if (ACPI_FAILURE(status))
504		return NULL;
505
506	dsd = buf->pointer;
507
508	/*
509	 * _DSD property consists tuples { Prop_UUID, Package() }
510	 * Iterate through all the packages and find the Graph.
511	 */
512	for (i = 0; i + 1 < dsd->package.count; i += 2) {
513		const union acpi_object *guid, *package;
514
515		guid = &dsd->package.elements[i];
516		package = &dsd->package.elements[i + 1];
517
518		/* All _DSD elements must have a UUID and a Package */
519		if (!is_acpi_guid(guid) || package->type != ACPI_TYPE_PACKAGE)
520			break;
521		/* Skip the non-Graph _DSD packages */
522		if (!is_acpi_dsd_graph_guid(guid))
523			continue;
524		if (acpi_validate_dsd_graph(package))
525			return package;
526		/* Invalid graph format, continue */
527		dev_warn(&adev->dev, "Invalid Graph _DSD property\n");
528	}
529
530	return NULL;
531}
532
533static inline bool
534acpi_validate_coresight_graph(const union acpi_object *cs_graph)
535{
536	int nlinks;
537
538	nlinks = cs_graph->package.elements[2].integer.value;
539	/*
540	 * Graph must have the following fields :
541	 * { GraphID, GraphUUID, NumberOfLinks, Links... }
542	 */
543	if (cs_graph->package.count != (nlinks + 3))
544		return false;
545	/* The links are validated in acpi_coresight_parse_link() */
546	return true;
547}
548
549/*
550 * acpi_get_coresight_graph	- Parse the device _DSD tables and find
551 * the Graph property matching the CoreSight Graphs.
552 *
553 * Returns the pointer to the CoreSight Graph Package when found. Otherwise
554 * returns NULL.
555 */
556static const union acpi_object *
557acpi_get_coresight_graph(struct acpi_device *adev, struct acpi_buffer *buf)
558{
559	const union acpi_object *graph_list, *graph;
560	int i, nr_graphs;
561
562	graph_list = acpi_get_dsd_graph(adev, buf);
563	if (!graph_list)
564		return graph_list;
565
566	nr_graphs = graph_list->package.elements[1].integer.value;
567
568	for (i = 2; i < nr_graphs + 2; i++) {
569		graph = &graph_list->package.elements[i];
570		if (!is_acpi_coresight_graph(graph))
571			continue;
572		if (acpi_validate_coresight_graph(graph))
573			return graph;
574		/* Invalid graph format */
575		break;
576	}
577
578	return NULL;
579}
580
581/*
582 * acpi_coresight_parse_link	- Parse the given Graph connection
583 * of the device and populate the coresight_connection for an output
584 * connection.
585 *
586 * CoreSight Graph specification mandates that the direction of the data
587 * flow must be specified in the link. i.e,
588 *
589 *	SourcePortAddress,	// Integer
590 *	DestinationPortAddress,	// Integer
591 *	DestinationDeviceName,	// Reference to another device
592 *	DirectionOfFlow,	// 1 for output(master), 0 for input(slave)
593 *
594 * Returns the direction of the data flow [ Input(slave) or Output(master) ]
595 * upon success.
596 * Returns an negative error number otherwise.
597 */
598static int acpi_coresight_parse_link(struct acpi_device *adev,
599				     const union acpi_object *link,
600				     struct coresight_connection *conn)
601{
602	int dir;
603	const union acpi_object *fields;
604	struct acpi_device *r_adev;
605	struct device *rdev;
606
607	if (link->type != ACPI_TYPE_PACKAGE ||
608	    link->package.count != 4)
609		return -EINVAL;
610
611	fields = link->package.elements;
612
613	if (fields[0].type != ACPI_TYPE_INTEGER ||
614	    fields[1].type != ACPI_TYPE_INTEGER ||
615	    fields[2].type != ACPI_TYPE_LOCAL_REFERENCE ||
616	    fields[3].type != ACPI_TYPE_INTEGER)
617		return -EINVAL;
618
619	r_adev = acpi_fetch_acpi_dev(fields[2].reference.handle);
620	if (!r_adev)
621		return -ENODEV;
622
623	dir = fields[3].integer.value;
624	if (dir == ACPI_CORESIGHT_LINK_MASTER) {
625		conn->src_port = fields[0].integer.value;
626		conn->dest_port = fields[1].integer.value;
627		rdev = coresight_find_device_by_fwnode(&r_adev->fwnode);
628		if (!rdev)
629			return -EPROBE_DEFER;
630		/*
631		 * Hold the refcount to the target device. This could be
632		 * released via:
633		 * 1) coresight_release_platform_data() if the probe fails or
634		 *    this device is unregistered.
635		 * 2) While removing the target device via
636		 *    coresight_remove_match().
637		 */
638		conn->dest_fwnode = fwnode_handle_get(&r_adev->fwnode);
639	} else if (dir == ACPI_CORESIGHT_LINK_SLAVE) {
640		/*
641		 * We are only interested in the port number
642		 * for the input ports at this component.
643		 * Store the port number in child_port.
644		 */
645		conn->dest_port = fields[0].integer.value;
646	} else {
647		/* Invalid direction */
648		return -EINVAL;
649	}
650
651	return dir;
652}
653
654/*
655 * acpi_coresight_parse_graph	- Parse the _DSD CoreSight graph
656 * connection information and populate the supplied coresight_platform_data
657 * instance.
658 */
659static int acpi_coresight_parse_graph(struct device *dev,
660				      struct acpi_device *adev,
661				      struct coresight_platform_data *pdata)
662{
663	int ret = 0;
664	int i, nlinks;
665	const union acpi_object *graph;
666	struct coresight_connection conn, zero_conn = {};
667	struct coresight_connection *new_conn;
668	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
669
670	graph = acpi_get_coresight_graph(adev, &buf);
671	/*
672	 * There are no graph connections, which is fine for some components.
673	 * e.g., ETE
674	 */
675	if (!graph)
676		goto free;
677
678	nlinks = graph->package.elements[2].integer.value;
679	if (!nlinks)
680		goto free;
681
682	for (i = 0; i < nlinks; i++) {
683		const union acpi_object *link = &graph->package.elements[3 + i];
684		int dir;
685
686		conn = zero_conn;
687		dir = acpi_coresight_parse_link(adev, link, &conn);
688		if (dir < 0) {
689			ret = dir;
690			goto free;
691		}
692
693		if (dir == ACPI_CORESIGHT_LINK_MASTER) {
694			new_conn = coresight_add_out_conn(dev, pdata, &conn);
695			if (IS_ERR(new_conn)) {
696				ret = PTR_ERR(new_conn);
697				goto free;
698			}
699		}
700	}
701
702free:
703	/*
704	 * When ACPI fails to alloc a buffer, it will free the buffer
705	 * created via ACPI_ALLOCATE_BUFFER and set to NULL.
706	 * ACPI_FREE can handle NULL pointers, so free it directly.
707	 */
708	ACPI_FREE(buf.pointer);
709	return ret;
710}
711
712/*
713 * acpi_handle_to_logical_cpuid - Map a given acpi_handle to the
714 * logical CPU id of the corresponding CPU device.
715 *
716 * Returns the logical CPU id when found. Otherwise returns >= nr_cpus_id.
717 */
718static int
719acpi_handle_to_logical_cpuid(acpi_handle handle)
720{
721	int i;
722	struct acpi_processor *pr;
723
724	for_each_possible_cpu(i) {
725		pr = per_cpu(processors, i);
726		if (pr && pr->handle == handle)
727			break;
728	}
729
730	return i;
731}
732
733/*
734 * acpi_coresigh_get_cpu - Find the logical CPU id of the CPU associated
735 * with this coresight device. With ACPI bindings, the CoreSight components
736 * are listed as child device of the associated CPU.
737 *
738 * Returns the logical CPU id when found. Otherwise returns 0.
739 */
740static int acpi_coresight_get_cpu(struct device *dev)
741{
742	int cpu;
743	acpi_handle cpu_handle;
744	acpi_status status;
745	struct acpi_device *adev = ACPI_COMPANION(dev);
746
747	if (!adev)
748		return -ENODEV;
749	status = acpi_get_parent(adev->handle, &cpu_handle);
750	if (ACPI_FAILURE(status))
751		return -ENODEV;
752
753	cpu = acpi_handle_to_logical_cpuid(cpu_handle);
754	if (cpu >= nr_cpu_ids)
755		return -ENODEV;
756	return cpu;
757}
758
759static int
760acpi_get_coresight_platform_data(struct device *dev,
761				 struct coresight_platform_data *pdata)
762{
763	struct acpi_device *adev;
764
765	adev = ACPI_COMPANION(dev);
766	if (!adev)
767		return -EINVAL;
768
769	return acpi_coresight_parse_graph(dev, adev, pdata);
770}
771
772#else
773
774static inline int
775acpi_get_coresight_platform_data(struct device *dev,
776				 struct coresight_platform_data *pdata)
777{
778	return -ENOENT;
779}
780
781static inline int acpi_coresight_get_cpu(struct device *dev)
782{
783	return -ENODEV;
784}
785#endif
786
787int coresight_get_cpu(struct device *dev)
788{
789	if (is_of_node(dev->fwnode))
790		return of_coresight_get_cpu(dev);
791	else if (is_acpi_device_node(dev->fwnode))
792		return acpi_coresight_get_cpu(dev);
793	return 0;
794}
795EXPORT_SYMBOL_GPL(coresight_get_cpu);
796
797struct coresight_platform_data *
798coresight_get_platform_data(struct device *dev)
799{
800	int ret = -ENOENT;
801	struct coresight_platform_data *pdata = NULL;
802	struct fwnode_handle *fwnode = dev_fwnode(dev);
803
804	if (IS_ERR_OR_NULL(fwnode))
805		goto error;
806
807	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
808	if (!pdata) {
809		ret = -ENOMEM;
810		goto error;
811	}
812
813	if (is_of_node(fwnode))
814		ret = of_get_coresight_platform_data(dev, pdata);
815	else if (is_acpi_device_node(fwnode))
816		ret = acpi_get_coresight_platform_data(dev, pdata);
817
818	if (!ret)
819		return pdata;
820error:
821	if (!IS_ERR_OR_NULL(pdata))
822		/* Cleanup the connection information */
823		coresight_release_platform_data(NULL, dev, pdata);
824	return ERR_PTR(ret);
825}
826EXPORT_SYMBOL_GPL(coresight_get_platform_data);
827