coresight-platform.c

  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 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 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		/*
247		 * Get the firmware node of the filter source through the
248		 * reference. This could be used to filter the source in
249		 * building path.
250		 */
251		conn.filter_src_fwnode =
252			fwnode_find_reference(&ep->fwnode, "filter-source", 0);
253		if (IS_ERR(conn.filter_src_fwnode)) {
254			conn.filter_src_fwnode = NULL;
255		} else {
256			conn.filter_src_dev =
257			 coresight_find_csdev_by_fwnode(conn.filter_src_fwnode);
258			if (conn.filter_src_dev &&
259			    !coresight_is_device_source(conn.filter_src_dev)) {
260				dev_warn(dev, "port %d: Filter handle is not a trace source : %s\n",
261					 conn.src_port, dev_name(&conn.filter_src_dev->dev));
262				conn.filter_src_dev = NULL;
263				conn.filter_src_fwnode = NULL;
264			}
265		}
266
267		new_conn = coresight_add_out_conn(dev, pdata, &conn);
268		if (IS_ERR_VALUE(new_conn)) {
269			fwnode_handle_put(conn.dest_fwnode);
270			return PTR_ERR(new_conn);
271		}
272		/* Connection record updated */
273	} while (0);
274
275	of_node_put(rparent);
276	of_node_put(rep);
277	put_device(rdev);
278
279	return ret;
280}
281
282static int of_get_coresight_platform_data(struct device *dev,
283					  struct coresight_platform_data *pdata)
284{
285	int ret = 0;
286	struct device_node *ep = NULL;
287	const struct device_node *parent = NULL;
288	bool legacy_binding = false;
289	struct device_node *node = dev->of_node;
290
291	parent = of_coresight_get_output_ports_node(node);
292	/*
293	 * If the DT uses obsoleted bindings, the ports are listed
294	 * under the device and we need to filter out the input
295	 * ports.
296	 */
297	if (!parent) {
298		/*
299		 * Avoid warnings in for_each_endpoint_of_node()
300		 * if the device doesn't have any graph connections
301		 */
302		if (!of_graph_is_present(node))
303			return 0;
304		legacy_binding = true;
305		parent = node;
306		dev_warn_once(dev, "Uses obsolete Coresight DT bindings\n");
307	}
308
309	/* Iterate through each output port to discover topology */
310	for_each_endpoint_of_node(parent, ep) {
311		/*
312		 * Legacy binding mixes input/output ports under the
313		 * same parent. So, skip the input ports if we are dealing
314		 * with legacy binding, as they processed with their
315		 * connected output ports.
316		 */
317		if (legacy_binding && of_coresight_legacy_ep_is_input(ep))
318			continue;
319
320		ret = of_coresight_parse_endpoint(dev, ep, pdata);
321		if (ret) {
322			of_node_put(ep);
323			return ret;
324		}
325	}
326
327	return 0;
328}
329#else
330static int
331of_get_coresight_platform_data(struct device *dev,
332			       struct coresight_platform_data *pdata)
333{
334	return -ENOENT;
335}
336
337static int of_coresight_get_cpu(struct device *dev)
338{
339	return -ENODEV;
340}
341#endif
342
343#ifdef CONFIG_ACPI
344
345#include <acpi/actypes.h>
346#include <acpi/processor.h>
347
348/* ACPI Graph _DSD UUID : "ab02a46b-74c7-45a2-bd68-f7d344ef2153" */
349static const guid_t acpi_graph_uuid = GUID_INIT(0xab02a46b, 0x74c7, 0x45a2,
350						0xbd, 0x68, 0xf7, 0xd3,
351						0x44, 0xef, 0x21, 0x53);
352/* Coresight ACPI Graph UUID : "3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd" */
353static const guid_t coresight_graph_uuid = GUID_INIT(0x3ecbc8b6, 0x1d0e, 0x4fb3,
354						     0x81, 0x07, 0xe6, 0x27,
355						     0xf8, 0x05, 0xc6, 0xcd);
356#define ACPI_CORESIGHT_LINK_SLAVE	0
357#define ACPI_CORESIGHT_LINK_MASTER	1
358
359static bool is_acpi_guid(const union acpi_object *obj)
360{
361	return (obj->type == ACPI_TYPE_BUFFER) && (obj->buffer.length == 16);
362}
363
364/*
365 * acpi_guid_matches	- Checks if the given object is a GUID object and
366 * that it matches the supplied the GUID.
367 */
368static bool acpi_guid_matches(const union acpi_object *obj,
369				   const guid_t *guid)
370{
371	return is_acpi_guid(obj) &&
372	       guid_equal((guid_t *)obj->buffer.pointer, guid);
373}
374
375static bool is_acpi_dsd_graph_guid(const union acpi_object *obj)
376{
377	return acpi_guid_matches(obj, &acpi_graph_uuid);
378}
379
380static bool is_acpi_coresight_graph_guid(const union acpi_object *obj)
381{
382	return acpi_guid_matches(obj, &coresight_graph_uuid);
383}
384
385static bool is_acpi_coresight_graph(const union acpi_object *obj)
386{
387	const union acpi_object *graphid, *guid, *links;
388
389	if (obj->type != ACPI_TYPE_PACKAGE ||
390	    obj->package.count < 3)
391		return false;
392
393	graphid = &obj->package.elements[0];
394	guid = &obj->package.elements[1];
395	links = &obj->package.elements[2];
396
397	if (graphid->type != ACPI_TYPE_INTEGER ||
398	    links->type != ACPI_TYPE_INTEGER)
399		return false;
400
401	return is_acpi_coresight_graph_guid(guid);
402}
403
404/*
405 * acpi_validate_dsd_graph	- Make sure the given _DSD graph conforms
406 * to the ACPI _DSD Graph specification.
407 *
408 * ACPI Devices Graph property has the following format:
409 *  {
410 *	Revision	- Integer, must be 0
411 *	NumberOfGraphs	- Integer, N indicating the following list.
412 *	Graph[1],
413 *	 ...
414 *	Graph[N]
415 *  }
416 *
417 * And each Graph entry has the following format:
418 *  {
419 *	GraphID		- Integer, identifying a graph the device belongs to.
420 *	UUID		- UUID identifying the specification that governs
421 *			  this graph. (e.g, see is_acpi_coresight_graph())
422 *	NumberOfLinks	- Number "N" of connections on this node of the graph.
423 *	Links[1]
424 *	...
425 *	Links[N]
426 *  }
427 *
428 * Where each "Links" entry has the following format:
429 *
430 * {
431 *	SourcePortAddress	- Integer
432 *	DestinationPortAddress	- Integer
433 *	DestinationDeviceName	- Reference to another device
434 *	( --- CoreSight specific extensions below ---)
435 *	DirectionOfFlow		- Integer 1 for output(master)
436 *				  0 for input(slave)
437 * }
438 *
439 * e.g:
440 * For a Funnel device
441 *
442 * Device(MFUN) {
443 *   ...
444 *
445 *   Name (_DSD, Package() {
446 *	// DSD Package contains tuples of {  Proeprty_Type_UUID, Package() }
447 *	ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), //Std. Property UUID
448 *	Package() {
449 *		Package(2) { "property-name", <property-value> }
450 *	},
451 *
452 *	ToUUID("ab02a46b-74c7-45a2-bd68-f7d344ef2153"), // ACPI Graph UUID
453 *	Package() {
454 *	  0,		// Revision
455 *	  1,		// NumberOfGraphs.
456 *	  Package() {	// Graph[0] Package
457 *	     1,		// GraphID
458 *	     // Coresight Graph UUID
459 *	     ToUUID("3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd"),
460 *	     3,		// NumberOfLinks aka ports
461 *	     // Link[0]: Output_0 -> Replicator:Input_0
462 *	     Package () { 0, 0, \_SB_.RPL0, 1 },
463 *	     // Link[1]: Input_0 <- Cluster0_Funnel0:Output_0
464 *	     Package () { 0, 0, \_SB_.CLU0.FUN0, 0 },
465 *	     // Link[2]: Input_1 <- Cluster1_Funnel0:Output_0
466 *	      Package () { 1, 0, \_SB_.CLU1.FUN0, 0 },
467 *	  }	// End of Graph[0] Package
468 *
469 *	}, // End of ACPI Graph Property
470 *  })
471 */
472static bool acpi_validate_dsd_graph(const union acpi_object *graph)
473{
474	int i, n;
475	const union acpi_object *rev, *nr_graphs;
476
477	/* The graph must contain at least the Revision and Number of Graphs */
478	if (graph->package.count < 2)
479		return false;
480
481	rev = &graph->package.elements[0];
482	nr_graphs = &graph->package.elements[1];
483
484	if (rev->type != ACPI_TYPE_INTEGER ||
485	    nr_graphs->type != ACPI_TYPE_INTEGER)
486		return false;
487
488	/* We only support revision 0 */
489	if (rev->integer.value != 0)
490		return false;
491
492	n = nr_graphs->integer.value;
493	/* CoreSight devices are only part of a single Graph */
494	if (n != 1)
495		return false;
496
497	/* Make sure the ACPI graph package has right number of elements */
498	if (graph->package.count != (n + 2))
499		return false;
500
501	/*
502	 * Each entry must be a graph package with at least 3 members :
503	 * { GraphID, UUID, NumberOfLinks(n), Links[.],... }
504	 */
505	for (i = 2; i < n + 2; i++) {
506		const union acpi_object *obj = &graph->package.elements[i];
507
508		if (obj->type != ACPI_TYPE_PACKAGE ||
509		    obj->package.count < 3)
510			return false;
511	}
512
513	return true;
514}
515
516/* acpi_get_dsd_graph	- Find the _DSD Graph property for the given device. */
517static const union acpi_object *
518acpi_get_dsd_graph(struct acpi_device *adev, struct acpi_buffer *buf)
519{
520	int i;
521	acpi_status status;
522	const union acpi_object *dsd;
523
524	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL,
525					    buf, ACPI_TYPE_PACKAGE);
526	if (ACPI_FAILURE(status))
527		return NULL;
528
529	dsd = buf->pointer;
530
531	/*
532	 * _DSD property consists tuples { Prop_UUID, Package() }
533	 * Iterate through all the packages and find the Graph.
534	 */
535	for (i = 0; i + 1 < dsd->package.count; i += 2) {
536		const union acpi_object *guid, *package;
537
538		guid = &dsd->package.elements[i];
539		package = &dsd->package.elements[i + 1];
540
541		/* All _DSD elements must have a UUID and a Package */
542		if (!is_acpi_guid(guid) || package->type != ACPI_TYPE_PACKAGE)
543			break;
544		/* Skip the non-Graph _DSD packages */
545		if (!is_acpi_dsd_graph_guid(guid))
546			continue;
547		if (acpi_validate_dsd_graph(package))
548			return package;
549		/* Invalid graph format, continue */
550		dev_warn(&adev->dev, "Invalid Graph _DSD property\n");
551	}
552
553	return NULL;
554}
555
556static bool
557acpi_validate_coresight_graph(const union acpi_object *cs_graph)
558{
559	int nlinks;
560
561	nlinks = cs_graph->package.elements[2].integer.value;
562	/*
563	 * Graph must have the following fields :
564	 * { GraphID, GraphUUID, NumberOfLinks, Links... }
565	 */
566	if (cs_graph->package.count != (nlinks + 3))
567		return false;
568	/* The links are validated in acpi_coresight_parse_link() */
569	return true;
570}
571
572/*
573 * acpi_get_coresight_graph	- Parse the device _DSD tables and find
574 * the Graph property matching the CoreSight Graphs.
575 *
576 * Returns the pointer to the CoreSight Graph Package when found. Otherwise
577 * returns NULL.
578 */
579static const union acpi_object *
580acpi_get_coresight_graph(struct acpi_device *adev, struct acpi_buffer *buf)
581{
582	const union acpi_object *graph_list, *graph;
583	int i, nr_graphs;
584
585	graph_list = acpi_get_dsd_graph(adev, buf);
586	if (!graph_list)
587		return graph_list;
588
589	nr_graphs = graph_list->package.elements[1].integer.value;
590
591	for (i = 2; i < nr_graphs + 2; i++) {
592		graph = &graph_list->package.elements[i];
593		if (!is_acpi_coresight_graph(graph))
594			continue;
595		if (acpi_validate_coresight_graph(graph))
596			return graph;
597		/* Invalid graph format */
598		break;
599	}
600
601	return NULL;
602}
603
604/*
605 * acpi_coresight_parse_link	- Parse the given Graph connection
606 * of the device and populate the coresight_connection for an output
607 * connection.
608 *
609 * CoreSight Graph specification mandates that the direction of the data
610 * flow must be specified in the link. i.e,
611 *
612 *	SourcePortAddress,	// Integer
613 *	DestinationPortAddress,	// Integer
614 *	DestinationDeviceName,	// Reference to another device
615 *	DirectionOfFlow,	// 1 for output(master), 0 for input(slave)
616 *
617 * Returns the direction of the data flow [ Input(slave) or Output(master) ]
618 * upon success.
619 * Returns an negative error number otherwise.
620 */
621static int acpi_coresight_parse_link(struct acpi_device *adev,
622				     const union acpi_object *link,
623				     struct coresight_connection *conn)
624{
625	int dir;
626	const union acpi_object *fields;
627	struct acpi_device *r_adev;
628	struct device *rdev;
629
630	if (link->type != ACPI_TYPE_PACKAGE ||
631	    link->package.count != 4)
632		return -EINVAL;
633
634	fields = link->package.elements;
635
636	if (fields[0].type != ACPI_TYPE_INTEGER ||
637	    fields[1].type != ACPI_TYPE_INTEGER ||
638	    fields[2].type != ACPI_TYPE_LOCAL_REFERENCE ||
639	    fields[3].type != ACPI_TYPE_INTEGER)
640		return -EINVAL;
641
642	r_adev = acpi_fetch_acpi_dev(fields[2].reference.handle);
643	if (!r_adev)
644		return -ENODEV;
645
646	dir = fields[3].integer.value;
647	if (dir == ACPI_CORESIGHT_LINK_MASTER) {
648		conn->src_port = fields[0].integer.value;
649		conn->dest_port = fields[1].integer.value;
650		rdev = coresight_find_device_by_fwnode(&r_adev->fwnode);
651		if (!rdev)
652			return -EPROBE_DEFER;
653		/*
654		 * Hold the refcount to the target device. This could be
655		 * released via:
656		 * 1) coresight_release_platform_data() if the probe fails or
657		 *    this device is unregistered.
658		 * 2) While removing the target device via
659		 *    coresight_remove_match().
660		 */
661		conn->dest_fwnode = fwnode_handle_get(&r_adev->fwnode);
662	} else if (dir == ACPI_CORESIGHT_LINK_SLAVE) {
663		/*
664		 * We are only interested in the port number
665		 * for the input ports at this component.
666		 * Store the port number in child_port.
667		 */
668		conn->dest_port = fields[0].integer.value;
669	} else {
670		/* Invalid direction */
671		return -EINVAL;
672	}
673
674	return dir;
675}
676
677/*
678 * acpi_coresight_parse_graph	- Parse the _DSD CoreSight graph
679 * connection information and populate the supplied coresight_platform_data
680 * instance.
681 */
682static int acpi_coresight_parse_graph(struct device *dev,
683				      struct acpi_device *adev,
684				      struct coresight_platform_data *pdata)
685{
686	int ret = 0;
687	int i, nlinks;
688	const union acpi_object *graph;
689	struct coresight_connection conn, zero_conn = {};
690	struct coresight_connection *new_conn;
691	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
692
693	graph = acpi_get_coresight_graph(adev, &buf);
694	/*
695	 * There are no graph connections, which is fine for some components.
696	 * e.g., ETE
697	 */
698	if (!graph)
699		goto free;
700
701	nlinks = graph->package.elements[2].integer.value;
702	if (!nlinks)
703		goto free;
704
705	for (i = 0; i < nlinks; i++) {
706		const union acpi_object *link = &graph->package.elements[3 + i];
707		int dir;
708
709		conn = zero_conn;
710		dir = acpi_coresight_parse_link(adev, link, &conn);
711		if (dir < 0) {
712			ret = dir;
713			goto free;
714		}
715
716		if (dir == ACPI_CORESIGHT_LINK_MASTER) {
717			new_conn = coresight_add_out_conn(dev, pdata, &conn);
718			if (IS_ERR(new_conn)) {
719				ret = PTR_ERR(new_conn);
720				goto free;
721			}
722		}
723	}
724
725free:
726	/*
727	 * When ACPI fails to alloc a buffer, it will free the buffer
728	 * created via ACPI_ALLOCATE_BUFFER and set to NULL.
729	 * ACPI_FREE can handle NULL pointers, so free it directly.
730	 */
731	ACPI_FREE(buf.pointer);
732	return ret;
733}
734
735/*
736 * acpi_handle_to_logical_cpuid - Map a given acpi_handle to the
737 * logical CPU id of the corresponding CPU device.
738 *
739 * Returns the logical CPU id when found. Otherwise returns >= nr_cpus_id.
740 */
741static int
742acpi_handle_to_logical_cpuid(acpi_handle handle)
743{
744	int i;
745	struct acpi_processor *pr;
746
747	for_each_possible_cpu(i) {
748		pr = per_cpu(processors, i);
749		if (pr && pr->handle == handle)
750			break;
751	}
752
753	return i;
754}
755
756/*
757 * acpi_coresigh_get_cpu - Find the logical CPU id of the CPU associated
758 * with this coresight device. With ACPI bindings, the CoreSight components
759 * are listed as child device of the associated CPU.
760 *
761 * Returns the logical CPU id when found. Otherwise returns 0.
762 */
763static int acpi_coresight_get_cpu(struct device *dev)
764{
765	int cpu;
766	acpi_handle cpu_handle;
767	acpi_status status;
768	struct acpi_device *adev = ACPI_COMPANION(dev);
769
770	if (!adev)
771		return -ENODEV;
772	status = acpi_get_parent(adev->handle, &cpu_handle);
773	if (ACPI_FAILURE(status))
774		return -ENODEV;
775
776	cpu = acpi_handle_to_logical_cpuid(cpu_handle);
777	if (cpu >= nr_cpu_ids)
778		return -ENODEV;
779	return cpu;
780}
781
782static int
783acpi_get_coresight_platform_data(struct device *dev,
784				 struct coresight_platform_data *pdata)
785{
786	struct acpi_device *adev;
787
788	adev = ACPI_COMPANION(dev);
789	if (!adev)
790		return -EINVAL;
791
792	return acpi_coresight_parse_graph(dev, adev, pdata);
793}
794
795#else
796
797static int
798acpi_get_coresight_platform_data(struct device *dev,
799				 struct coresight_platform_data *pdata)
800{
801	return -ENOENT;
802}
803
804static int acpi_coresight_get_cpu(struct device *dev)
805{
806	return -ENODEV;
807}
808#endif
809
810int coresight_get_cpu(struct device *dev)
811{
812	if (is_of_node(dev->fwnode))
813		return of_coresight_get_cpu(dev);
814	else if (is_acpi_device_node(dev->fwnode))
815		return acpi_coresight_get_cpu(dev);
816	return 0;
817}
818EXPORT_SYMBOL_GPL(coresight_get_cpu);
819
820int coresight_get_static_trace_id(struct device *dev, u32 *id)
821{
822	return fwnode_property_read_u32(dev_fwnode(dev), "arm,static-trace-id", id);
823}
824EXPORT_SYMBOL_GPL(coresight_get_static_trace_id);
825
826struct coresight_platform_data *
827coresight_get_platform_data(struct device *dev)
828{
829	int ret = -ENOENT;
830	struct coresight_platform_data *pdata = NULL;
831	struct fwnode_handle *fwnode = dev_fwnode(dev);
832
833	if (IS_ERR_OR_NULL(fwnode))
834		goto error;
835
836	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
837	if (!pdata) {
838		ret = -ENOMEM;
839		goto error;
840	}
841
842	if (is_of_node(fwnode))
843		ret = of_get_coresight_platform_data(dev, pdata);
844	else if (is_acpi_device_node(fwnode))
845		ret = acpi_get_coresight_platform_data(dev, pdata);
846
847	if (!ret)
848		return pdata;
849error:
850	if (!IS_ERR_OR_NULL(pdata))
851		/* Cleanup the connection information */
852		coresight_release_platform_data(NULL, dev, pdata);
853	return ERR_PTR(ret);
854}
855EXPORT_SYMBOL_GPL(coresight_get_platform_data);