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1// SPDX-License-Identifier: GPL-2.02/*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 -EINVAL25 */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 the62	 * end of the connection array and also return it in case it needs to be63	 * 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 array73 *74 * @out_conn: Existing output connection to store as an input on the75 *	      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 the107	 * 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 bus115	 * 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 the123 * csdev keeps a copy so iterate round the coresight bus to124 * 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_OF142static 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 we153	 * 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 @ep188 * and fill the connection information in @pdata->out_conns189 *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 is215		 * 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 be237		 * released via:238		 * 1) coresight_release_platform_data() if the probe fails or239		 *    this device is unregistered.240		 * 2) While removing the target device via241		 *    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 listed273	 * under the device and we need to filter out the input274	 * ports.275	 */276	if (!parent) {277		/*278		 * Avoid warnings in for_each_endpoint_of_node()279		 * if the device doesn't have any graph connections280		 */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	for_each_endpoint_of_node(parent, ep) {290		/*291		 * Legacy binding mixes input/output ports under the292		 * same parent. So, skip the input ports if we are dealing293		 * with legacy binding, as they processed with their294		 * 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			of_node_put(ep);302			return ret;303		}304	}305 306	return 0;307}308#else309static inline int310of_get_coresight_platform_data(struct device *dev,311			       struct coresight_platform_data *pdata)312{313	return -ENOENT;314}315 316static inline int of_coresight_get_cpu(struct device *dev)317{318	return -ENODEV;319}320#endif321 322#ifdef CONFIG_ACPI323 324#include <acpi/actypes.h>325#include <acpi/processor.h>326 327/* ACPI Graph _DSD UUID : "ab02a46b-74c7-45a2-bd68-f7d344ef2153" */328static const guid_t acpi_graph_uuid = GUID_INIT(0xab02a46b, 0x74c7, 0x45a2,329						0xbd, 0x68, 0xf7, 0xd3,330						0x44, 0xef, 0x21, 0x53);331/* Coresight ACPI Graph UUID : "3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd" */332static const guid_t coresight_graph_uuid = GUID_INIT(0x3ecbc8b6, 0x1d0e, 0x4fb3,333						     0x81, 0x07, 0xe6, 0x27,334						     0xf8, 0x05, 0xc6, 0xcd);335#define ACPI_CORESIGHT_LINK_SLAVE	0336#define ACPI_CORESIGHT_LINK_MASTER	1337 338static inline bool is_acpi_guid(const union acpi_object *obj)339{340	return (obj->type == ACPI_TYPE_BUFFER) && (obj->buffer.length == 16);341}342 343/*344 * acpi_guid_matches	- Checks if the given object is a GUID object and345 * that it matches the supplied the GUID.346 */347static inline bool acpi_guid_matches(const union acpi_object *obj,348				   const guid_t *guid)349{350	return is_acpi_guid(obj) &&351	       guid_equal((guid_t *)obj->buffer.pointer, guid);352}353 354static inline bool is_acpi_dsd_graph_guid(const union acpi_object *obj)355{356	return acpi_guid_matches(obj, &acpi_graph_uuid);357}358 359static inline bool is_acpi_coresight_graph_guid(const union acpi_object *obj)360{361	return acpi_guid_matches(obj, &coresight_graph_uuid);362}363 364static inline bool is_acpi_coresight_graph(const union acpi_object *obj)365{366	const union acpi_object *graphid, *guid, *links;367 368	if (obj->type != ACPI_TYPE_PACKAGE ||369	    obj->package.count < 3)370		return false;371 372	graphid = &obj->package.elements[0];373	guid = &obj->package.elements[1];374	links = &obj->package.elements[2];375 376	if (graphid->type != ACPI_TYPE_INTEGER ||377	    links->type != ACPI_TYPE_INTEGER)378		return false;379 380	return is_acpi_coresight_graph_guid(guid);381}382 383/*384 * acpi_validate_dsd_graph	- Make sure the given _DSD graph conforms385 * to the ACPI _DSD Graph specification.386 *387 * ACPI Devices Graph property has the following format:388 *  {389 *	Revision	- Integer, must be 0390 *	NumberOfGraphs	- Integer, N indicating the following list.391 *	Graph[1],392 *	 ...393 *	Graph[N]394 *  }395 *396 * And each Graph entry has the following format:397 *  {398 *	GraphID		- Integer, identifying a graph the device belongs to.399 *	UUID		- UUID identifying the specification that governs400 *			  this graph. (e.g, see is_acpi_coresight_graph())401 *	NumberOfLinks	- Number "N" of connections on this node of the graph.402 *	Links[1]403 *	...404 *	Links[N]405 *  }406 *407 * Where each "Links" entry has the following format:408 *409 * {410 *	SourcePortAddress	- Integer411 *	DestinationPortAddress	- Integer412 *	DestinationDeviceName	- Reference to another device413 *	( --- CoreSight specific extensions below ---)414 *	DirectionOfFlow		- Integer 1 for output(master)415 *				  0 for input(slave)416 * }417 *418 * e.g:419 * For a Funnel device420 *421 * Device(MFUN) {422 *   ...423 *424 *   Name (_DSD, Package() {425 *	// DSD Package contains tuples of {  Proeprty_Type_UUID, Package() }426 *	ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), //Std. Property UUID427 *	Package() {428 *		Package(2) { "property-name", <property-value> }429 *	},430 *431 *	ToUUID("ab02a46b-74c7-45a2-bd68-f7d344ef2153"), // ACPI Graph UUID432 *	Package() {433 *	  0,		// Revision434 *	  1,		// NumberOfGraphs.435 *	  Package() {	// Graph[0] Package436 *	     1,		// GraphID437 *	     // Coresight Graph UUID438 *	     ToUUID("3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd"),439 *	     3,		// NumberOfLinks aka ports440 *	     // Link[0]: Output_0 -> Replicator:Input_0441 *	     Package () { 0, 0, \_SB_.RPL0, 1 },442 *	     // Link[1]: Input_0 <- Cluster0_Funnel0:Output_0443 *	     Package () { 0, 0, \_SB_.CLU0.FUN0, 0 },444 *	     // Link[2]: Input_1 <- Cluster1_Funnel0:Output_0445 *	      Package () { 1, 0, \_SB_.CLU1.FUN0, 0 },446 *	  }	// End of Graph[0] Package447 *448 *	}, // End of ACPI Graph Property449 *  })450 */451static inline bool acpi_validate_dsd_graph(const union acpi_object *graph)452{453	int i, n;454	const union acpi_object *rev, *nr_graphs;455 456	/* The graph must contain at least the Revision and Number of Graphs */457	if (graph->package.count < 2)458		return false;459 460	rev = &graph->package.elements[0];461	nr_graphs = &graph->package.elements[1];462 463	if (rev->type != ACPI_TYPE_INTEGER ||464	    nr_graphs->type != ACPI_TYPE_INTEGER)465		return false;466 467	/* We only support revision 0 */468	if (rev->integer.value != 0)469		return false;470 471	n = nr_graphs->integer.value;472	/* CoreSight devices are only part of a single Graph */473	if (n != 1)474		return false;475 476	/* Make sure the ACPI graph package has right number of elements */477	if (graph->package.count != (n + 2))478		return false;479 480	/*481	 * Each entry must be a graph package with at least 3 members :482	 * { GraphID, UUID, NumberOfLinks(n), Links[.],... }483	 */484	for (i = 2; i < n + 2; i++) {485		const union acpi_object *obj = &graph->package.elements[i];486 487		if (obj->type != ACPI_TYPE_PACKAGE ||488		    obj->package.count < 3)489			return false;490	}491 492	return true;493}494 495/* acpi_get_dsd_graph	- Find the _DSD Graph property for the given device. */496static const union acpi_object *497acpi_get_dsd_graph(struct acpi_device *adev, struct acpi_buffer *buf)498{499	int i;500	acpi_status status;501	const union acpi_object *dsd;502 503	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL,504					    buf, ACPI_TYPE_PACKAGE);505	if (ACPI_FAILURE(status))506		return NULL;507 508	dsd = buf->pointer;509 510	/*511	 * _DSD property consists tuples { Prop_UUID, Package() }512	 * Iterate through all the packages and find the Graph.513	 */514	for (i = 0; i + 1 < dsd->package.count; i += 2) {515		const union acpi_object *guid, *package;516 517		guid = &dsd->package.elements[i];518		package = &dsd->package.elements[i + 1];519 520		/* All _DSD elements must have a UUID and a Package */521		if (!is_acpi_guid(guid) || package->type != ACPI_TYPE_PACKAGE)522			break;523		/* Skip the non-Graph _DSD packages */524		if (!is_acpi_dsd_graph_guid(guid))525			continue;526		if (acpi_validate_dsd_graph(package))527			return package;528		/* Invalid graph format, continue */529		dev_warn(&adev->dev, "Invalid Graph _DSD property\n");530	}531 532	return NULL;533}534 535static inline bool536acpi_validate_coresight_graph(const union acpi_object *cs_graph)537{538	int nlinks;539 540	nlinks = cs_graph->package.elements[2].integer.value;541	/*542	 * Graph must have the following fields :543	 * { GraphID, GraphUUID, NumberOfLinks, Links... }544	 */545	if (cs_graph->package.count != (nlinks + 3))546		return false;547	/* The links are validated in acpi_coresight_parse_link() */548	return true;549}550 551/*552 * acpi_get_coresight_graph	- Parse the device _DSD tables and find553 * the Graph property matching the CoreSight Graphs.554 *555 * Returns the pointer to the CoreSight Graph Package when found. Otherwise556 * returns NULL.557 */558static const union acpi_object *559acpi_get_coresight_graph(struct acpi_device *adev, struct acpi_buffer *buf)560{561	const union acpi_object *graph_list, *graph;562	int i, nr_graphs;563 564	graph_list = acpi_get_dsd_graph(adev, buf);565	if (!graph_list)566		return graph_list;567 568	nr_graphs = graph_list->package.elements[1].integer.value;569 570	for (i = 2; i < nr_graphs + 2; i++) {571		graph = &graph_list->package.elements[i];572		if (!is_acpi_coresight_graph(graph))573			continue;574		if (acpi_validate_coresight_graph(graph))575			return graph;576		/* Invalid graph format */577		break;578	}579 580	return NULL;581}582 583/*584 * acpi_coresight_parse_link	- Parse the given Graph connection585 * of the device and populate the coresight_connection for an output586 * connection.587 *588 * CoreSight Graph specification mandates that the direction of the data589 * flow must be specified in the link. i.e,590 *591 *	SourcePortAddress,	// Integer592 *	DestinationPortAddress,	// Integer593 *	DestinationDeviceName,	// Reference to another device594 *	DirectionOfFlow,	// 1 for output(master), 0 for input(slave)595 *596 * Returns the direction of the data flow [ Input(slave) or Output(master) ]597 * upon success.598 * Returns an negative error number otherwise.599 */600static int acpi_coresight_parse_link(struct acpi_device *adev,601				     const union acpi_object *link,602				     struct coresight_connection *conn)603{604	int dir;605	const union acpi_object *fields;606	struct acpi_device *r_adev;607	struct device *rdev;608 609	if (link->type != ACPI_TYPE_PACKAGE ||610	    link->package.count != 4)611		return -EINVAL;612 613	fields = link->package.elements;614 615	if (fields[0].type != ACPI_TYPE_INTEGER ||616	    fields[1].type != ACPI_TYPE_INTEGER ||617	    fields[2].type != ACPI_TYPE_LOCAL_REFERENCE ||618	    fields[3].type != ACPI_TYPE_INTEGER)619		return -EINVAL;620 621	r_adev = acpi_fetch_acpi_dev(fields[2].reference.handle);622	if (!r_adev)623		return -ENODEV;624 625	dir = fields[3].integer.value;626	if (dir == ACPI_CORESIGHT_LINK_MASTER) {627		conn->src_port = fields[0].integer.value;628		conn->dest_port = fields[1].integer.value;629		rdev = coresight_find_device_by_fwnode(&r_adev->fwnode);630		if (!rdev)631			return -EPROBE_DEFER;632		/*633		 * Hold the refcount to the target device. This could be634		 * released via:635		 * 1) coresight_release_platform_data() if the probe fails or636		 *    this device is unregistered.637		 * 2) While removing the target device via638		 *    coresight_remove_match().639		 */640		conn->dest_fwnode = fwnode_handle_get(&r_adev->fwnode);641	} else if (dir == ACPI_CORESIGHT_LINK_SLAVE) {642		/*643		 * We are only interested in the port number644		 * for the input ports at this component.645		 * Store the port number in child_port.646		 */647		conn->dest_port = fields[0].integer.value;648	} else {649		/* Invalid direction */650		return -EINVAL;651	}652 653	return dir;654}655 656/*657 * acpi_coresight_parse_graph	- Parse the _DSD CoreSight graph658 * connection information and populate the supplied coresight_platform_data659 * instance.660 */661static int acpi_coresight_parse_graph(struct device *dev,662				      struct acpi_device *adev,663				      struct coresight_platform_data *pdata)664{665	int ret = 0;666	int i, nlinks;667	const union acpi_object *graph;668	struct coresight_connection conn, zero_conn = {};669	struct coresight_connection *new_conn;670	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };671 672	graph = acpi_get_coresight_graph(adev, &buf);673	/*674	 * There are no graph connections, which is fine for some components.675	 * e.g., ETE676	 */677	if (!graph)678		goto free;679 680	nlinks = graph->package.elements[2].integer.value;681	if (!nlinks)682		goto free;683 684	for (i = 0; i < nlinks; i++) {685		const union acpi_object *link = &graph->package.elements[3 + i];686		int dir;687 688		conn = zero_conn;689		dir = acpi_coresight_parse_link(adev, link, &conn);690		if (dir < 0) {691			ret = dir;692			goto free;693		}694 695		if (dir == ACPI_CORESIGHT_LINK_MASTER) {696			new_conn = coresight_add_out_conn(dev, pdata, &conn);697			if (IS_ERR(new_conn)) {698				ret = PTR_ERR(new_conn);699				goto free;700			}701		}702	}703 704free:705	/*706	 * When ACPI fails to alloc a buffer, it will free the buffer707	 * created via ACPI_ALLOCATE_BUFFER and set to NULL.708	 * ACPI_FREE can handle NULL pointers, so free it directly.709	 */710	ACPI_FREE(buf.pointer);711	return ret;712}713 714/*715 * acpi_handle_to_logical_cpuid - Map a given acpi_handle to the716 * logical CPU id of the corresponding CPU device.717 *718 * Returns the logical CPU id when found. Otherwise returns >= nr_cpus_id.719 */720static int721acpi_handle_to_logical_cpuid(acpi_handle handle)722{723	int i;724	struct acpi_processor *pr;725 726	for_each_possible_cpu(i) {727		pr = per_cpu(processors, i);728		if (pr && pr->handle == handle)729			break;730	}731 732	return i;733}734 735/*736 * acpi_coresigh_get_cpu - Find the logical CPU id of the CPU associated737 * with this coresight device. With ACPI bindings, the CoreSight components738 * are listed as child device of the associated CPU.739 *740 * Returns the logical CPU id when found. Otherwise returns 0.741 */742static int acpi_coresight_get_cpu(struct device *dev)743{744	int cpu;745	acpi_handle cpu_handle;746	acpi_status status;747	struct acpi_device *adev = ACPI_COMPANION(dev);748 749	if (!adev)750		return -ENODEV;751	status = acpi_get_parent(adev->handle, &cpu_handle);752	if (ACPI_FAILURE(status))753		return -ENODEV;754 755	cpu = acpi_handle_to_logical_cpuid(cpu_handle);756	if (cpu >= nr_cpu_ids)757		return -ENODEV;758	return cpu;759}760 761static int762acpi_get_coresight_platform_data(struct device *dev,763				 struct coresight_platform_data *pdata)764{765	struct acpi_device *adev;766 767	adev = ACPI_COMPANION(dev);768	if (!adev)769		return -EINVAL;770 771	return acpi_coresight_parse_graph(dev, adev, pdata);772}773 774#else775 776static inline int777acpi_get_coresight_platform_data(struct device *dev,778				 struct coresight_platform_data *pdata)779{780	return -ENOENT;781}782 783static inline int acpi_coresight_get_cpu(struct device *dev)784{785	return -ENODEV;786}787#endif788 789int coresight_get_cpu(struct device *dev)790{791	if (is_of_node(dev->fwnode))792		return of_coresight_get_cpu(dev);793	else if (is_acpi_device_node(dev->fwnode))794		return acpi_coresight_get_cpu(dev);795	return 0;796}797EXPORT_SYMBOL_GPL(coresight_get_cpu);798 799struct coresight_platform_data *800coresight_get_platform_data(struct device *dev)801{802	int ret = -ENOENT;803	struct coresight_platform_data *pdata = NULL;804	struct fwnode_handle *fwnode = dev_fwnode(dev);805 806	if (IS_ERR_OR_NULL(fwnode))807		goto error;808 809	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);810	if (!pdata) {811		ret = -ENOMEM;812		goto error;813	}814 815	if (is_of_node(fwnode))816		ret = of_get_coresight_platform_data(dev, pdata);817	else if (is_acpi_device_node(fwnode))818		ret = acpi_get_coresight_platform_data(dev, pdata);819 820	if (!ret)821		return pdata;822error:823	if (!IS_ERR_OR_NULL(pdata))824		/* Cleanup the connection information */825		coresight_release_platform_data(NULL, dev, pdata);826	return ERR_PTR(ret);827}828EXPORT_SYMBOL_GPL(coresight_get_platform_data);829