Linux Audio

Check our new training course

Buildroot integration, development and maintenance

Need a Buildroot system for your embedded project?
Loading...
v6.2
  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 */
 26static int coresight_alloc_conns(struct device *dev,
 27				 struct coresight_platform_data *pdata)
 28{
 29	if (pdata->nr_outport) {
 30		pdata->conns = devm_kcalloc(dev, pdata->nr_outport,
 31					    sizeof(*pdata->conns), GFP_KERNEL);
 32		if (!pdata->conns)
 33			return -ENOMEM;
 34	}
 35
 36	return 0;
 37}
 38
 39static struct device *
 40coresight_find_device_by_fwnode(struct fwnode_handle *fwnode)
 41{
 42	struct device *dev = NULL;
 43
 44	/*
 45	 * If we have a non-configurable replicator, it will be found on the
 46	 * platform bus.
 47	 */
 48	dev = bus_find_device_by_fwnode(&platform_bus_type, fwnode);
 49	if (dev)
 50		return dev;
 51
 52	/*
 53	 * We have a configurable component - circle through the AMBA bus
 54	 * looking for the device that matches the endpoint node.
 55	 */
 56	return bus_find_device_by_fwnode(&amba_bustype, fwnode);
 57}
 58
 59/*
 60 * Find a registered coresight device from a device fwnode.
 61 * The node info is associated with the AMBA parent, but the
 62 * csdev keeps a copy so iterate round the coresight bus to
 63 * find the device.
 64 */
 65struct coresight_device *
 66coresight_find_csdev_by_fwnode(struct fwnode_handle *r_fwnode)
 67{
 68	struct device *dev;
 69	struct coresight_device *csdev = NULL;
 70
 71	dev = bus_find_device_by_fwnode(&coresight_bustype, r_fwnode);
 72	if (dev) {
 73		csdev = to_coresight_device(dev);
 74		put_device(dev);
 75	}
 76	return csdev;
 77}
 78EXPORT_SYMBOL_GPL(coresight_find_csdev_by_fwnode);
 79
 80#ifdef CONFIG_OF
 81static inline bool of_coresight_legacy_ep_is_input(struct device_node *ep)
 82{
 83	return of_property_read_bool(ep, "slave-mode");
 84}
 85
 86static void of_coresight_get_ports_legacy(const struct device_node *node,
 87					  int *nr_inport, int *nr_outport)
 88{
 89	struct device_node *ep = NULL;
 90	struct of_endpoint endpoint;
 91	int in = 0, out = 0;
 92
 93	/*
 94	 * Avoid warnings in of_graph_get_next_endpoint()
 95	 * if the device doesn't have any graph connections
 96	 */
 97	if (!of_graph_is_present(node))
 98		return;
 99	do {
100		ep = of_graph_get_next_endpoint(node, ep);
101		if (!ep)
102			break;
103
104		if (of_graph_parse_endpoint(ep, &endpoint))
105			continue;
106
107		if (of_coresight_legacy_ep_is_input(ep)) {
108			in = (endpoint.port + 1 > in) ?
109				endpoint.port + 1 : in;
110		} else {
111			out = (endpoint.port + 1) > out ?
112				endpoint.port + 1 : out;
113		}
114
115	} while (ep);
116
117	*nr_inport = in;
118	*nr_outport = out;
119}
120
121static struct device_node *of_coresight_get_port_parent(struct device_node *ep)
122{
123	struct device_node *parent = of_graph_get_port_parent(ep);
124
125	/*
126	 * Skip one-level up to the real device node, if we
127	 * are using the new bindings.
128	 */
129	if (of_node_name_eq(parent, "in-ports") ||
130	    of_node_name_eq(parent, "out-ports"))
131		parent = of_get_next_parent(parent);
132
133	return parent;
134}
135
136static inline struct device_node *
137of_coresight_get_input_ports_node(const struct device_node *node)
138{
139	return of_get_child_by_name(node, "in-ports");
140}
141
142static inline struct device_node *
143of_coresight_get_output_ports_node(const struct device_node *node)
144{
145	return of_get_child_by_name(node, "out-ports");
146}
147
148static inline int
149of_coresight_count_ports(struct device_node *port_parent)
150{
151	int i = 0;
152	struct device_node *ep = NULL;
153	struct of_endpoint endpoint;
154
155	while ((ep = of_graph_get_next_endpoint(port_parent, ep))) {
156		/* Defer error handling to parsing */
157		if (of_graph_parse_endpoint(ep, &endpoint))
158			continue;
159		if (endpoint.port + 1 > i)
160			i = endpoint.port + 1;
161	}
162
163	return i;
164}
165
166static void of_coresight_get_ports(const struct device_node *node,
167				   int *nr_inport, int *nr_outport)
168{
169	struct device_node *input_ports = NULL, *output_ports = NULL;
170
171	input_ports = of_coresight_get_input_ports_node(node);
172	output_ports = of_coresight_get_output_ports_node(node);
173
174	if (input_ports || output_ports) {
175		if (input_ports) {
176			*nr_inport = of_coresight_count_ports(input_ports);
177			of_node_put(input_ports);
178		}
179		if (output_ports) {
180			*nr_outport = of_coresight_count_ports(output_ports);
181			of_node_put(output_ports);
182		}
183	} else {
184		/* Fall back to legacy DT bindings parsing */
185		of_coresight_get_ports_legacy(node, nr_inport, nr_outport);
186	}
187}
188
189static int of_coresight_get_cpu(struct device *dev)
190{
191	int cpu;
192	struct device_node *dn;
193
194	if (!dev->of_node)
195		return -ENODEV;
196
197	dn = of_parse_phandle(dev->of_node, "cpu", 0);
198	if (!dn)
199		return -ENODEV;
200
201	cpu = of_cpu_node_to_id(dn);
202	of_node_put(dn);
203
204	return cpu;
205}
206
207/*
208 * of_coresight_parse_endpoint : Parse the given output endpoint @ep
209 * and fill the connection information in @conn
210 *
211 * Parses the local port, remote device name and the remote port.
212 *
213 * Returns :
214 *	 0	- If the parsing completed without any fatal errors.
215 *	-Errno	- Fatal error, abort the scanning.
216 */
217static int of_coresight_parse_endpoint(struct device *dev,
218				       struct device_node *ep,
219				       struct coresight_platform_data *pdata)
220{
221	int ret = 0;
222	struct of_endpoint endpoint, rendpoint;
223	struct device_node *rparent = NULL;
224	struct device_node *rep = NULL;
225	struct device *rdev = NULL;
226	struct fwnode_handle *rdev_fwnode;
227	struct coresight_connection *conn;
228
229	do {
230		/* Parse the local port details */
231		if (of_graph_parse_endpoint(ep, &endpoint))
232			break;
233		/*
234		 * Get a handle on the remote endpoint and the device it is
235		 * attached to.
236		 */
237		rep = of_graph_get_remote_endpoint(ep);
238		if (!rep)
239			break;
240		rparent = of_coresight_get_port_parent(rep);
241		if (!rparent)
242			break;
243		if (of_graph_parse_endpoint(rep, &rendpoint))
244			break;
245
246		rdev_fwnode = of_fwnode_handle(rparent);
247		/* If the remote device is not available, defer probing */
248		rdev = coresight_find_device_by_fwnode(rdev_fwnode);
249		if (!rdev) {
250			ret = -EPROBE_DEFER;
251			break;
252		}
253
254		conn = &pdata->conns[endpoint.port];
255		if (conn->child_fwnode) {
256			dev_warn(dev, "Duplicate output port %d\n",
257				 endpoint.port);
258			ret = -EINVAL;
259			break;
260		}
261		conn->outport = endpoint.port;
262		/*
263		 * Hold the refcount to the target device. This could be
264		 * released via:
265		 * 1) coresight_release_platform_data() if the probe fails or
266		 *    this device is unregistered.
267		 * 2) While removing the target device via
268		 *    coresight_remove_match()
269		 */
270		conn->child_fwnode = fwnode_handle_get(rdev_fwnode);
271		conn->child_port = rendpoint.port;
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	/* Get the number of input and output port for this component */
292	of_coresight_get_ports(node, &pdata->nr_inport, &pdata->nr_outport);
293
294	/* If there are no output connections, we are done */
295	if (!pdata->nr_outport)
296		return 0;
297
298	ret = coresight_alloc_conns(dev, pdata);
299	if (ret)
300		return ret;
301
302	parent = of_coresight_get_output_ports_node(node);
303	/*
304	 * If the DT uses obsoleted bindings, the ports are listed
305	 * under the device and we need to filter out the input
306	 * ports.
307	 */
308	if (!parent) {
309		legacy_binding = true;
310		parent = node;
311		dev_warn_once(dev, "Uses obsolete Coresight DT bindings\n");
312	}
313
314	/* Iterate through each output port to discover topology */
315	while ((ep = of_graph_get_next_endpoint(parent, ep))) {
316		/*
317		 * Legacy binding mixes input/output ports under the
318		 * same parent. So, skip the input ports if we are dealing
319		 * with legacy binding, as they processed with their
320		 * connected output ports.
321		 */
322		if (legacy_binding && of_coresight_legacy_ep_is_input(ep))
323			continue;
324
325		ret = of_coresight_parse_endpoint(dev, ep, pdata);
326		if (ret)
327			return ret;
328	}
329
330	return 0;
331}
332#else
333static inline int
334of_get_coresight_platform_data(struct device *dev,
335			       struct coresight_platform_data *pdata)
336{
337	return -ENOENT;
338}
339
340static inline int of_coresight_get_cpu(struct device *dev)
341{
342	return -ENODEV;
343}
344#endif
345
346#ifdef CONFIG_ACPI
347
348#include <acpi/actypes.h>
349#include <acpi/processor.h>
350
351/* ACPI Graph _DSD UUID : "ab02a46b-74c7-45a2-bd68-f7d344ef2153" */
352static const guid_t acpi_graph_uuid = GUID_INIT(0xab02a46b, 0x74c7, 0x45a2,
353						0xbd, 0x68, 0xf7, 0xd3,
354						0x44, 0xef, 0x21, 0x53);
355/* Coresight ACPI Graph UUID : "3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd" */
356static const guid_t coresight_graph_uuid = GUID_INIT(0x3ecbc8b6, 0x1d0e, 0x4fb3,
357						     0x81, 0x07, 0xe6, 0x27,
358						     0xf8, 0x05, 0xc6, 0xcd);
359#define ACPI_CORESIGHT_LINK_SLAVE	0
360#define ACPI_CORESIGHT_LINK_MASTER	1
361
362static inline bool is_acpi_guid(const union acpi_object *obj)
363{
364	return (obj->type == ACPI_TYPE_BUFFER) && (obj->buffer.length == 16);
365}
366
367/*
368 * acpi_guid_matches	- Checks if the given object is a GUID object and
369 * that it matches the supplied the GUID.
370 */
371static inline bool acpi_guid_matches(const union acpi_object *obj,
372				   const guid_t *guid)
373{
374	return is_acpi_guid(obj) &&
375	       guid_equal((guid_t *)obj->buffer.pointer, guid);
376}
377
378static inline bool is_acpi_dsd_graph_guid(const union acpi_object *obj)
379{
380	return acpi_guid_matches(obj, &acpi_graph_uuid);
381}
382
383static inline bool is_acpi_coresight_graph_guid(const union acpi_object *obj)
384{
385	return acpi_guid_matches(obj, &coresight_graph_uuid);
386}
387
388static inline bool is_acpi_coresight_graph(const union acpi_object *obj)
389{
390	const union acpi_object *graphid, *guid, *links;
391
392	if (obj->type != ACPI_TYPE_PACKAGE ||
393	    obj->package.count < 3)
394		return false;
395
396	graphid = &obj->package.elements[0];
397	guid = &obj->package.elements[1];
398	links = &obj->package.elements[2];
399
400	if (graphid->type != ACPI_TYPE_INTEGER ||
401	    links->type != ACPI_TYPE_INTEGER)
402		return false;
403
404	return is_acpi_coresight_graph_guid(guid);
405}
406
407/*
408 * acpi_validate_dsd_graph	- Make sure the given _DSD graph conforms
409 * to the ACPI _DSD Graph specification.
410 *
411 * ACPI Devices Graph property has the following format:
412 *  {
413 *	Revision	- Integer, must be 0
414 *	NumberOfGraphs	- Integer, N indicating the following list.
415 *	Graph[1],
416 *	 ...
417 *	Graph[N]
418 *  }
419 *
420 * And each Graph entry has the following format:
421 *  {
422 *	GraphID		- Integer, identifying a graph the device belongs to.
423 *	UUID		- UUID identifying the specification that governs
424 *			  this graph. (e.g, see is_acpi_coresight_graph())
425 *	NumberOfLinks	- Number "N" of connections on this node of the graph.
426 *	Links[1]
427 *	...
428 *	Links[N]
429 *  }
430 *
431 * Where each "Links" entry has the following format:
432 *
433 * {
434 *	SourcePortAddress	- Integer
435 *	DestinationPortAddress	- Integer
436 *	DestinationDeviceName	- Reference to another device
437 *	( --- CoreSight specific extensions below ---)
438 *	DirectionOfFlow		- Integer 1 for output(master)
439 *				  0 for input(slave)
440 * }
441 *
442 * e.g:
443 * For a Funnel device
444 *
445 * Device(MFUN) {
446 *   ...
447 *
448 *   Name (_DSD, Package() {
449 *	// DSD Package contains tuples of {  Proeprty_Type_UUID, Package() }
450 *	ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), //Std. Property UUID
451 *	Package() {
452 *		Package(2) { "property-name", <property-value> }
453 *	},
454 *
455 *	ToUUID("ab02a46b-74c7-45a2-bd68-f7d344ef2153"), // ACPI Graph UUID
456 *	Package() {
457 *	  0,		// Revision
458 *	  1,		// NumberOfGraphs.
459 *	  Package() {	// Graph[0] Package
460 *	     1,		// GraphID
461 *	     // Coresight Graph UUID
462 *	     ToUUID("3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd"),
463 *	     3,		// NumberOfLinks aka ports
464 *	     // Link[0]: Output_0 -> Replicator:Input_0
465 *	     Package () { 0, 0, \_SB_.RPL0, 1 },
466 *	     // Link[1]: Input_0 <- Cluster0_Funnel0:Output_0
467 *	     Package () { 0, 0, \_SB_.CLU0.FUN0, 0 },
468 *	     // Link[2]: Input_1 <- Cluster1_Funnel0:Output_0
469 *	      Package () { 1, 0, \_SB_.CLU1.FUN0, 0 },
470 *	  }	// End of Graph[0] Package
471 *
472 *	}, // End of ACPI Graph Property
473 *  })
474 */
475static inline bool acpi_validate_dsd_graph(const union acpi_object *graph)
476{
477	int i, n;
478	const union acpi_object *rev, *nr_graphs;
479
480	/* The graph must contain at least the Revision and Number of Graphs */
481	if (graph->package.count < 2)
482		return false;
483
484	rev = &graph->package.elements[0];
485	nr_graphs = &graph->package.elements[1];
486
487	if (rev->type != ACPI_TYPE_INTEGER ||
488	    nr_graphs->type != ACPI_TYPE_INTEGER)
489		return false;
490
491	/* We only support revision 0 */
492	if (rev->integer.value != 0)
493		return false;
494
495	n = nr_graphs->integer.value;
496	/* CoreSight devices are only part of a single Graph */
497	if (n != 1)
498		return false;
499
500	/* Make sure the ACPI graph package has right number of elements */
501	if (graph->package.count != (n + 2))
502		return false;
503
504	/*
505	 * Each entry must be a graph package with at least 3 members :
506	 * { GraphID, UUID, NumberOfLinks(n), Links[.],... }
507	 */
508	for (i = 2; i < n + 2; i++) {
509		const union acpi_object *obj = &graph->package.elements[i];
510
511		if (obj->type != ACPI_TYPE_PACKAGE ||
512		    obj->package.count < 3)
513			return false;
514	}
515
516	return true;
517}
518
519/* acpi_get_dsd_graph	- Find the _DSD Graph property for the given device. */
520static const union acpi_object *
521acpi_get_dsd_graph(struct acpi_device *adev)
522{
523	int i;
524	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
525	acpi_status status;
526	const union acpi_object *dsd;
527
528	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL,
529					    &buf, ACPI_TYPE_PACKAGE);
530	if (ACPI_FAILURE(status))
531		return NULL;
532
533	dsd = buf.pointer;
534
535	/*
536	 * _DSD property consists tuples { Prop_UUID, Package() }
537	 * Iterate through all the packages and find the Graph.
538	 */
539	for (i = 0; i + 1 < dsd->package.count; i += 2) {
540		const union acpi_object *guid, *package;
541
542		guid = &dsd->package.elements[i];
543		package = &dsd->package.elements[i + 1];
544
545		/* All _DSD elements must have a UUID and a Package */
546		if (!is_acpi_guid(guid) || package->type != ACPI_TYPE_PACKAGE)
547			break;
548		/* Skip the non-Graph _DSD packages */
549		if (!is_acpi_dsd_graph_guid(guid))
550			continue;
551		if (acpi_validate_dsd_graph(package))
552			return package;
553		/* Invalid graph format, continue */
554		dev_warn(&adev->dev, "Invalid Graph _DSD property\n");
555	}
556
557	return NULL;
558}
559
560static inline bool
561acpi_validate_coresight_graph(const union acpi_object *cs_graph)
562{
563	int nlinks;
564
565	nlinks = cs_graph->package.elements[2].integer.value;
566	/*
567	 * Graph must have the following fields :
568	 * { GraphID, GraphUUID, NumberOfLinks, Links... }
569	 */
570	if (cs_graph->package.count != (nlinks + 3))
571		return false;
572	/* The links are validated in acpi_coresight_parse_link() */
573	return true;
574}
575
576/*
577 * acpi_get_coresight_graph	- Parse the device _DSD tables and find
578 * the Graph property matching the CoreSight Graphs.
579 *
580 * Returns the pointer to the CoreSight Graph Package when found. Otherwise
581 * returns NULL.
582 */
583static const union acpi_object *
584acpi_get_coresight_graph(struct acpi_device *adev)
585{
586	const union acpi_object *graph_list, *graph;
587	int i, nr_graphs;
588
589	graph_list = acpi_get_dsd_graph(adev);
590	if (!graph_list)
591		return graph_list;
592
593	nr_graphs = graph_list->package.elements[1].integer.value;
594
595	for (i = 2; i < nr_graphs + 2; i++) {
596		graph = &graph_list->package.elements[i];
597		if (!is_acpi_coresight_graph(graph))
598			continue;
599		if (acpi_validate_coresight_graph(graph))
600			return graph;
601		/* Invalid graph format */
602		break;
603	}
604
605	return NULL;
606}
607
608/*
609 * acpi_coresight_parse_link	- Parse the given Graph connection
610 * of the device and populate the coresight_connection for an output
611 * connection.
612 *
613 * CoreSight Graph specification mandates that the direction of the data
614 * flow must be specified in the link. i.e,
615 *
616 *	SourcePortAddress,	// Integer
617 *	DestinationPortAddress,	// Integer
618 *	DestinationDeviceName,	// Reference to another device
619 *	DirectionOfFlow,	// 1 for output(master), 0 for input(slave)
620 *
621 * Returns the direction of the data flow [ Input(slave) or Output(master) ]
622 * upon success.
623 * Returns an negative error number otherwise.
624 */
625static int acpi_coresight_parse_link(struct acpi_device *adev,
626				     const union acpi_object *link,
627				     struct coresight_connection *conn)
628{
629	int dir;
630	const union acpi_object *fields;
631	struct acpi_device *r_adev;
632	struct device *rdev;
633
634	if (link->type != ACPI_TYPE_PACKAGE ||
635	    link->package.count != 4)
636		return -EINVAL;
637
638	fields = link->package.elements;
639
640	if (fields[0].type != ACPI_TYPE_INTEGER ||
641	    fields[1].type != ACPI_TYPE_INTEGER ||
642	    fields[2].type != ACPI_TYPE_LOCAL_REFERENCE ||
643	    fields[3].type != ACPI_TYPE_INTEGER)
644		return -EINVAL;
645
646	r_adev = acpi_fetch_acpi_dev(fields[2].reference.handle);
647	if (!r_adev)
648		return -ENODEV;
649
650	dir = fields[3].integer.value;
651	if (dir == ACPI_CORESIGHT_LINK_MASTER) {
652		conn->outport = fields[0].integer.value;
653		conn->child_port = fields[1].integer.value;
654		rdev = coresight_find_device_by_fwnode(&r_adev->fwnode);
655		if (!rdev)
656			return -EPROBE_DEFER;
657		/*
658		 * Hold the refcount to the target device. This could be
659		 * released via:
660		 * 1) coresight_release_platform_data() if the probe fails or
661		 *    this device is unregistered.
662		 * 2) While removing the target device via
663		 *    coresight_remove_match().
664		 */
665		conn->child_fwnode = fwnode_handle_get(&r_adev->fwnode);
666	} else if (dir == ACPI_CORESIGHT_LINK_SLAVE) {
667		/*
668		 * We are only interested in the port number
669		 * for the input ports at this component.
670		 * Store the port number in child_port.
671		 */
672		conn->child_port = fields[0].integer.value;
673	} else {
674		/* Invalid direction */
675		return -EINVAL;
676	}
677
678	return dir;
679}
680
681/*
682 * acpi_coresight_parse_graph	- Parse the _DSD CoreSight graph
683 * connection information and populate the supplied coresight_platform_data
684 * instance.
685 */
686static int acpi_coresight_parse_graph(struct acpi_device *adev,
687				      struct coresight_platform_data *pdata)
688{
689	int rc, i, nlinks;
690	const union acpi_object *graph;
691	struct coresight_connection *conns, *ptr;
692
693	pdata->nr_inport = pdata->nr_outport = 0;
694	graph = acpi_get_coresight_graph(adev);
695	if (!graph)
696		return -ENOENT;
697
698	nlinks = graph->package.elements[2].integer.value;
699	if (!nlinks)
700		return 0;
701
702	/*
703	 * To avoid scanning the table twice (once for finding the number of
704	 * output links and then later for parsing the output links),
705	 * cache the links information in one go and then later copy
706	 * it to the pdata.
707	 */
708	conns = devm_kcalloc(&adev->dev, nlinks, sizeof(*conns), GFP_KERNEL);
709	if (!conns)
710		return -ENOMEM;
711	ptr = conns;
712	for (i = 0; i < nlinks; i++) {
713		const union acpi_object *link = &graph->package.elements[3 + i];
714		int dir;
715
716		dir = acpi_coresight_parse_link(adev, link, ptr);
717		if (dir < 0)
718			return dir;
719
720		if (dir == ACPI_CORESIGHT_LINK_MASTER) {
721			if (ptr->outport >= pdata->nr_outport)
722				pdata->nr_outport = ptr->outport + 1;
723			ptr++;
724		} else {
725			WARN_ON(pdata->nr_inport == ptr->child_port + 1);
726			/*
727			 * We do not track input port connections for a device.
728			 * However we need the highest port number described,
729			 * which can be recorded now and reuse this connection
730			 * record for an output connection. Hence, do not move
731			 * the ptr for input connections
732			 */
733			if (ptr->child_port >= pdata->nr_inport)
734				pdata->nr_inport = ptr->child_port + 1;
735		}
736	}
737
738	rc = coresight_alloc_conns(&adev->dev, pdata);
739	if (rc)
740		return rc;
741
742	/* Copy the connection information to the final location */
743	for (i = 0; conns + i < ptr; i++) {
744		int port = conns[i].outport;
745
746		/* Duplicate output port */
747		WARN_ON(pdata->conns[port].child_fwnode);
748		pdata->conns[port] = conns[i];
749	}
750
751	devm_kfree(&adev->dev, conns);
752	return 0;
753}
754
755/*
756 * acpi_handle_to_logical_cpuid - Map a given acpi_handle to the
757 * logical CPU id of the corresponding CPU device.
758 *
759 * Returns the logical CPU id when found. Otherwise returns >= nr_cpus_id.
760 */
761static int
762acpi_handle_to_logical_cpuid(acpi_handle handle)
763{
764	int i;
765	struct acpi_processor *pr;
766
767	for_each_possible_cpu(i) {
768		pr = per_cpu(processors, i);
769		if (pr && pr->handle == handle)
770			break;
771	}
772
773	return i;
774}
775
776/*
777 * acpi_coresigh_get_cpu - Find the logical CPU id of the CPU associated
778 * with this coresight device. With ACPI bindings, the CoreSight components
779 * are listed as child device of the associated CPU.
780 *
781 * Returns the logical CPU id when found. Otherwise returns 0.
782 */
783static int acpi_coresight_get_cpu(struct device *dev)
784{
785	int cpu;
786	acpi_handle cpu_handle;
787	acpi_status status;
788	struct acpi_device *adev = ACPI_COMPANION(dev);
789
790	if (!adev)
791		return -ENODEV;
792	status = acpi_get_parent(adev->handle, &cpu_handle);
793	if (ACPI_FAILURE(status))
794		return -ENODEV;
795
796	cpu = acpi_handle_to_logical_cpuid(cpu_handle);
797	if (cpu >= nr_cpu_ids)
798		return -ENODEV;
799	return cpu;
800}
801
802static int
803acpi_get_coresight_platform_data(struct device *dev,
804				 struct coresight_platform_data *pdata)
805{
806	struct acpi_device *adev;
807
808	adev = ACPI_COMPANION(dev);
809	if (!adev)
810		return -EINVAL;
811
812	return acpi_coresight_parse_graph(adev, pdata);
813}
814
815#else
816
817static inline int
818acpi_get_coresight_platform_data(struct device *dev,
819				 struct coresight_platform_data *pdata)
820{
821	return -ENOENT;
822}
823
824static inline int acpi_coresight_get_cpu(struct device *dev)
825{
826	return -ENODEV;
827}
828#endif
829
830int coresight_get_cpu(struct device *dev)
831{
832	if (is_of_node(dev->fwnode))
833		return of_coresight_get_cpu(dev);
834	else if (is_acpi_device_node(dev->fwnode))
835		return acpi_coresight_get_cpu(dev);
836	return 0;
837}
838EXPORT_SYMBOL_GPL(coresight_get_cpu);
839
840struct coresight_platform_data *
841coresight_get_platform_data(struct device *dev)
842{
843	int ret = -ENOENT;
844	struct coresight_platform_data *pdata = NULL;
845	struct fwnode_handle *fwnode = dev_fwnode(dev);
846
847	if (IS_ERR_OR_NULL(fwnode))
848		goto error;
849
850	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
851	if (!pdata) {
852		ret = -ENOMEM;
853		goto error;
854	}
855
856	if (is_of_node(fwnode))
857		ret = of_get_coresight_platform_data(dev, pdata);
858	else if (is_acpi_device_node(fwnode))
859		ret = acpi_get_coresight_platform_data(dev, pdata);
860
861	if (!ret)
862		return pdata;
863error:
864	if (!IS_ERR_OR_NULL(pdata))
865		/* Cleanup the connection information */
866		coresight_release_platform_data(NULL, pdata);
867	return ERR_PTR(ret);
868}
869EXPORT_SYMBOL_GPL(coresight_get_platform_data);
v5.9
  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 */
 26static int coresight_alloc_conns(struct device *dev,
 27				 struct coresight_platform_data *pdata)
 28{
 29	if (pdata->nr_outport) {
 30		pdata->conns = devm_kcalloc(dev, pdata->nr_outport,
 31					    sizeof(*pdata->conns), GFP_KERNEL);
 32		if (!pdata->conns)
 33			return -ENOMEM;
 34	}
 35
 36	return 0;
 37}
 38
 39static struct device *
 40coresight_find_device_by_fwnode(struct fwnode_handle *fwnode)
 41{
 42	struct device *dev = NULL;
 43
 44	/*
 45	 * If we have a non-configurable replicator, it will be found on the
 46	 * platform bus.
 47	 */
 48	dev = bus_find_device_by_fwnode(&platform_bus_type, fwnode);
 49	if (dev)
 50		return dev;
 51
 52	/*
 53	 * We have a configurable component - circle through the AMBA bus
 54	 * looking for the device that matches the endpoint node.
 55	 */
 56	return bus_find_device_by_fwnode(&amba_bustype, fwnode);
 57}
 58
 59/*
 60 * Find a registered coresight device from a device fwnode.
 61 * The node info is associated with the AMBA parent, but the
 62 * csdev keeps a copy so iterate round the coresight bus to
 63 * find the device.
 64 */
 65struct coresight_device *
 66coresight_find_csdev_by_fwnode(struct fwnode_handle *r_fwnode)
 67{
 68	struct device *dev;
 69	struct coresight_device *csdev = NULL;
 70
 71	dev = bus_find_device_by_fwnode(&coresight_bustype, r_fwnode);
 72	if (dev) {
 73		csdev = to_coresight_device(dev);
 74		put_device(dev);
 75	}
 76	return csdev;
 77}
 
 78
 79#ifdef CONFIG_OF
 80static inline bool of_coresight_legacy_ep_is_input(struct device_node *ep)
 81{
 82	return of_property_read_bool(ep, "slave-mode");
 83}
 84
 85static void of_coresight_get_ports_legacy(const struct device_node *node,
 86					  int *nr_inport, int *nr_outport)
 87{
 88	struct device_node *ep = NULL;
 89	struct of_endpoint endpoint;
 90	int in = 0, out = 0;
 91
 
 
 
 
 
 
 92	do {
 93		ep = of_graph_get_next_endpoint(node, ep);
 94		if (!ep)
 95			break;
 96
 97		if (of_graph_parse_endpoint(ep, &endpoint))
 98			continue;
 99
100		if (of_coresight_legacy_ep_is_input(ep)) {
101			in = (endpoint.port + 1 > in) ?
102				endpoint.port + 1 : in;
103		} else {
104			out = (endpoint.port + 1) > out ?
105				endpoint.port + 1 : out;
106		}
107
108	} while (ep);
109
110	*nr_inport = in;
111	*nr_outport = out;
112}
113
114static struct device_node *of_coresight_get_port_parent(struct device_node *ep)
115{
116	struct device_node *parent = of_graph_get_port_parent(ep);
117
118	/*
119	 * Skip one-level up to the real device node, if we
120	 * are using the new bindings.
121	 */
122	if (of_node_name_eq(parent, "in-ports") ||
123	    of_node_name_eq(parent, "out-ports"))
124		parent = of_get_next_parent(parent);
125
126	return parent;
127}
128
129static inline struct device_node *
130of_coresight_get_input_ports_node(const struct device_node *node)
131{
132	return of_get_child_by_name(node, "in-ports");
133}
134
135static inline struct device_node *
136of_coresight_get_output_ports_node(const struct device_node *node)
137{
138	return of_get_child_by_name(node, "out-ports");
139}
140
141static inline int
142of_coresight_count_ports(struct device_node *port_parent)
143{
144	int i = 0;
145	struct device_node *ep = NULL;
146	struct of_endpoint endpoint;
147
148	while ((ep = of_graph_get_next_endpoint(port_parent, ep))) {
149		/* Defer error handling to parsing */
150		if (of_graph_parse_endpoint(ep, &endpoint))
151			continue;
152		if (endpoint.port + 1 > i)
153			i = endpoint.port + 1;
154	}
155
156	return i;
157}
158
159static void of_coresight_get_ports(const struct device_node *node,
160				   int *nr_inport, int *nr_outport)
161{
162	struct device_node *input_ports = NULL, *output_ports = NULL;
163
164	input_ports = of_coresight_get_input_ports_node(node);
165	output_ports = of_coresight_get_output_ports_node(node);
166
167	if (input_ports || output_ports) {
168		if (input_ports) {
169			*nr_inport = of_coresight_count_ports(input_ports);
170			of_node_put(input_ports);
171		}
172		if (output_ports) {
173			*nr_outport = of_coresight_count_ports(output_ports);
174			of_node_put(output_ports);
175		}
176	} else {
177		/* Fall back to legacy DT bindings parsing */
178		of_coresight_get_ports_legacy(node, nr_inport, nr_outport);
179	}
180}
181
182static int of_coresight_get_cpu(struct device *dev)
183{
184	int cpu;
185	struct device_node *dn;
186
187	if (!dev->of_node)
188		return -ENODEV;
189
190	dn = of_parse_phandle(dev->of_node, "cpu", 0);
191	if (!dn)
192		return -ENODEV;
193
194	cpu = of_cpu_node_to_id(dn);
195	of_node_put(dn);
196
197	return cpu;
198}
199
200/*
201 * of_coresight_parse_endpoint : Parse the given output endpoint @ep
202 * and fill the connection information in @conn
203 *
204 * Parses the local port, remote device name and the remote port.
205 *
206 * Returns :
207 *	 0	- If the parsing completed without any fatal errors.
208 *	-Errno	- Fatal error, abort the scanning.
209 */
210static int of_coresight_parse_endpoint(struct device *dev,
211				       struct device_node *ep,
212				       struct coresight_platform_data *pdata)
213{
214	int ret = 0;
215	struct of_endpoint endpoint, rendpoint;
216	struct device_node *rparent = NULL;
217	struct device_node *rep = NULL;
218	struct device *rdev = NULL;
219	struct fwnode_handle *rdev_fwnode;
220	struct coresight_connection *conn;
221
222	do {
223		/* Parse the local port details */
224		if (of_graph_parse_endpoint(ep, &endpoint))
225			break;
226		/*
227		 * Get a handle on the remote endpoint and the device it is
228		 * attached to.
229		 */
230		rep = of_graph_get_remote_endpoint(ep);
231		if (!rep)
232			break;
233		rparent = of_coresight_get_port_parent(rep);
234		if (!rparent)
235			break;
236		if (of_graph_parse_endpoint(rep, &rendpoint))
237			break;
238
239		rdev_fwnode = of_fwnode_handle(rparent);
240		/* If the remote device is not available, defer probing */
241		rdev = coresight_find_device_by_fwnode(rdev_fwnode);
242		if (!rdev) {
243			ret = -EPROBE_DEFER;
244			break;
245		}
246
247		conn = &pdata->conns[endpoint.port];
248		if (conn->child_fwnode) {
249			dev_warn(dev, "Duplicate output port %d\n",
250				 endpoint.port);
251			ret = -EINVAL;
252			break;
253		}
254		conn->outport = endpoint.port;
255		/*
256		 * Hold the refcount to the target device. This could be
257		 * released via:
258		 * 1) coresight_release_platform_data() if the probe fails or
259		 *    this device is unregistered.
260		 * 2) While removing the target device via
261		 *    coresight_remove_match()
262		 */
263		conn->child_fwnode = fwnode_handle_get(rdev_fwnode);
264		conn->child_port = rendpoint.port;
265		/* Connection record updated */
266	} while (0);
267
268	of_node_put(rparent);
269	of_node_put(rep);
270	put_device(rdev);
271
272	return ret;
273}
274
275static int of_get_coresight_platform_data(struct device *dev,
276					  struct coresight_platform_data *pdata)
277{
278	int ret = 0;
279	struct device_node *ep = NULL;
280	const struct device_node *parent = NULL;
281	bool legacy_binding = false;
282	struct device_node *node = dev->of_node;
283
284	/* Get the number of input and output port for this component */
285	of_coresight_get_ports(node, &pdata->nr_inport, &pdata->nr_outport);
286
287	/* If there are no output connections, we are done */
288	if (!pdata->nr_outport)
289		return 0;
290
291	ret = coresight_alloc_conns(dev, pdata);
292	if (ret)
293		return ret;
294
295	parent = of_coresight_get_output_ports_node(node);
296	/*
297	 * If the DT uses obsoleted bindings, the ports are listed
298	 * under the device and we need to filter out the input
299	 * ports.
300	 */
301	if (!parent) {
302		legacy_binding = true;
303		parent = node;
304		dev_warn_once(dev, "Uses obsolete Coresight DT bindings\n");
305	}
306
307	/* Iterate through each output port to discover topology */
308	while ((ep = of_graph_get_next_endpoint(parent, ep))) {
309		/*
310		 * Legacy binding mixes input/output ports under the
311		 * same parent. So, skip the input ports if we are dealing
312		 * with legacy binding, as they processed with their
313		 * connected output ports.
314		 */
315		if (legacy_binding && of_coresight_legacy_ep_is_input(ep))
316			continue;
317
318		ret = of_coresight_parse_endpoint(dev, ep, pdata);
319		if (ret)
320			return ret;
321	}
322
323	return 0;
324}
325#else
326static inline int
327of_get_coresight_platform_data(struct device *dev,
328			       struct coresight_platform_data *pdata)
329{
330	return -ENOENT;
331}
332
333static inline int of_coresight_get_cpu(struct device *dev)
334{
335	return -ENODEV;
336}
337#endif
338
339#ifdef CONFIG_ACPI
340
341#include <acpi/actypes.h>
342#include <acpi/processor.h>
343
344/* ACPI Graph _DSD UUID : "ab02a46b-74c7-45a2-bd68-f7d344ef2153" */
345static const guid_t acpi_graph_uuid = GUID_INIT(0xab02a46b, 0x74c7, 0x45a2,
346						0xbd, 0x68, 0xf7, 0xd3,
347						0x44, 0xef, 0x21, 0x53);
348/* Coresight ACPI Graph UUID : "3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd" */
349static const guid_t coresight_graph_uuid = GUID_INIT(0x3ecbc8b6, 0x1d0e, 0x4fb3,
350						     0x81, 0x07, 0xe6, 0x27,
351						     0xf8, 0x05, 0xc6, 0xcd);
352#define ACPI_CORESIGHT_LINK_SLAVE	0
353#define ACPI_CORESIGHT_LINK_MASTER	1
354
355static inline bool is_acpi_guid(const union acpi_object *obj)
356{
357	return (obj->type == ACPI_TYPE_BUFFER) && (obj->buffer.length == 16);
358}
359
360/*
361 * acpi_guid_matches	- Checks if the given object is a GUID object and
362 * that it matches the supplied the GUID.
363 */
364static inline bool acpi_guid_matches(const union acpi_object *obj,
365				   const guid_t *guid)
366{
367	return is_acpi_guid(obj) &&
368	       guid_equal((guid_t *)obj->buffer.pointer, guid);
369}
370
371static inline bool is_acpi_dsd_graph_guid(const union acpi_object *obj)
372{
373	return acpi_guid_matches(obj, &acpi_graph_uuid);
374}
375
376static inline bool is_acpi_coresight_graph_guid(const union acpi_object *obj)
377{
378	return acpi_guid_matches(obj, &coresight_graph_uuid);
379}
380
381static inline bool is_acpi_coresight_graph(const union acpi_object *obj)
382{
383	const union acpi_object *graphid, *guid, *links;
384
385	if (obj->type != ACPI_TYPE_PACKAGE ||
386	    obj->package.count < 3)
387		return false;
388
389	graphid = &obj->package.elements[0];
390	guid = &obj->package.elements[1];
391	links = &obj->package.elements[2];
392
393	if (graphid->type != ACPI_TYPE_INTEGER ||
394	    links->type != ACPI_TYPE_INTEGER)
395		return false;
396
397	return is_acpi_coresight_graph_guid(guid);
398}
399
400/*
401 * acpi_validate_dsd_graph	- Make sure the given _DSD graph conforms
402 * to the ACPI _DSD Graph specification.
403 *
404 * ACPI Devices Graph property has the following format:
405 *  {
406 *	Revision	- Integer, must be 0
407 *	NumberOfGraphs	- Integer, N indicating the following list.
408 *	Graph[1],
409 *	 ...
410 *	Graph[N]
411 *  }
412 *
413 * And each Graph entry has the following format:
414 *  {
415 *	GraphID		- Integer, identifying a graph the device belongs to.
416 *	UUID		- UUID identifying the specification that governs
417 *			  this graph. (e.g, see is_acpi_coresight_graph())
418 *	NumberOfLinks	- Number "N" of connections on this node of the graph.
419 *	Links[1]
420 *	...
421 *	Links[N]
422 *  }
423 *
424 * Where each "Links" entry has the following format:
425 *
426 * {
427 *	SourcePortAddress	- Integer
428 *	DestinationPortAddress	- Integer
429 *	DestinationDeviceName	- Reference to another device
430 *	( --- CoreSight specific extensions below ---)
431 *	DirectionOfFlow		- Integer 1 for output(master)
432 *				  0 for input(slave)
433 * }
434 *
435 * e.g:
436 * For a Funnel device
437 *
438 * Device(MFUN) {
439 *   ...
440 *
441 *   Name (_DSD, Package() {
442 *	// DSD Package contains tuples of {  Proeprty_Type_UUID, Package() }
443 *	ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), //Std. Property UUID
444 *	Package() {
445 *		Package(2) { "property-name", <property-value> }
446 *	},
447 *
448 *	ToUUID("ab02a46b-74c7-45a2-bd68-f7d344ef2153"), // ACPI Graph UUID
449 *	Package() {
450 *	  0,		// Revision
451 *	  1,		// NumberOfGraphs.
452 *	  Package() {	// Graph[0] Package
453 *	     1,		// GraphID
454 *	     // Coresight Graph UUID
455 *	     ToUUID("3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd"),
456 *	     3,		// NumberOfLinks aka ports
457 *	     // Link[0]: Output_0 -> Replicator:Input_0
458 *	     Package () { 0, 0, \_SB_.RPL0, 1 },
459 *	     // Link[1]: Input_0 <- Cluster0_Funnel0:Output_0
460 *	     Package () { 0, 0, \_SB_.CLU0.FUN0, 0 },
461 *	     // Link[2]: Input_1 <- Cluster1_Funnel0:Output_0
462 *	      Package () { 1, 0, \_SB_.CLU1.FUN0, 0 },
463 *	  }	// End of Graph[0] Package
464 *
465 *	}, // End of ACPI Graph Property
466 *  })
467 */
468static inline bool acpi_validate_dsd_graph(const union acpi_object *graph)
469{
470	int i, n;
471	const union acpi_object *rev, *nr_graphs;
472
473	/* The graph must contain at least the Revision and Number of Graphs */
474	if (graph->package.count < 2)
475		return false;
476
477	rev = &graph->package.elements[0];
478	nr_graphs = &graph->package.elements[1];
479
480	if (rev->type != ACPI_TYPE_INTEGER ||
481	    nr_graphs->type != ACPI_TYPE_INTEGER)
482		return false;
483
484	/* We only support revision 0 */
485	if (rev->integer.value != 0)
486		return false;
487
488	n = nr_graphs->integer.value;
489	/* CoreSight devices are only part of a single Graph */
490	if (n != 1)
491		return false;
492
493	/* Make sure the ACPI graph package has right number of elements */
494	if (graph->package.count != (n + 2))
495		return false;
496
497	/*
498	 * Each entry must be a graph package with at least 3 members :
499	 * { GraphID, UUID, NumberOfLinks(n), Links[.],... }
500	 */
501	for (i = 2; i < n + 2; i++) {
502		const union acpi_object *obj = &graph->package.elements[i];
503
504		if (obj->type != ACPI_TYPE_PACKAGE ||
505		    obj->package.count < 3)
506			return false;
507	}
508
509	return true;
510}
511
512/* acpi_get_dsd_graph	- Find the _DSD Graph property for the given device. */
513static const union acpi_object *
514acpi_get_dsd_graph(struct acpi_device *adev)
515{
516	int i;
517	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
518	acpi_status status;
519	const union acpi_object *dsd;
520
521	status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL,
522					    &buf, ACPI_TYPE_PACKAGE);
523	if (ACPI_FAILURE(status))
524		return NULL;
525
526	dsd = buf.pointer;
527
528	/*
529	 * _DSD property consists tuples { Prop_UUID, Package() }
530	 * Iterate through all the packages and find the Graph.
531	 */
532	for (i = 0; i + 1 < dsd->package.count; i += 2) {
533		const union acpi_object *guid, *package;
534
535		guid = &dsd->package.elements[i];
536		package = &dsd->package.elements[i + 1];
537
538		/* All _DSD elements must have a UUID and a Package */
539		if (!is_acpi_guid(guid) || package->type != ACPI_TYPE_PACKAGE)
540			break;
541		/* Skip the non-Graph _DSD packages */
542		if (!is_acpi_dsd_graph_guid(guid))
543			continue;
544		if (acpi_validate_dsd_graph(package))
545			return package;
546		/* Invalid graph format, continue */
547		dev_warn(&adev->dev, "Invalid Graph _DSD property\n");
548	}
549
550	return NULL;
551}
552
553static inline bool
554acpi_validate_coresight_graph(const union acpi_object *cs_graph)
555{
556	int nlinks;
557
558	nlinks = cs_graph->package.elements[2].integer.value;
559	/*
560	 * Graph must have the following fields :
561	 * { GraphID, GraphUUID, NumberOfLinks, Links... }
562	 */
563	if (cs_graph->package.count != (nlinks + 3))
564		return false;
565	/* The links are validated in acpi_coresight_parse_link() */
566	return true;
567}
568
569/*
570 * acpi_get_coresight_graph	- Parse the device _DSD tables and find
571 * the Graph property matching the CoreSight Graphs.
572 *
573 * Returns the pointer to the CoreSight Graph Package when found. Otherwise
574 * returns NULL.
575 */
576static const union acpi_object *
577acpi_get_coresight_graph(struct acpi_device *adev)
578{
579	const union acpi_object *graph_list, *graph;
580	int i, nr_graphs;
581
582	graph_list = acpi_get_dsd_graph(adev);
583	if (!graph_list)
584		return graph_list;
585
586	nr_graphs = graph_list->package.elements[1].integer.value;
587
588	for (i = 2; i < nr_graphs + 2; i++) {
589		graph = &graph_list->package.elements[i];
590		if (!is_acpi_coresight_graph(graph))
591			continue;
592		if (acpi_validate_coresight_graph(graph))
593			return graph;
594		/* Invalid graph format */
595		break;
596	}
597
598	return NULL;
599}
600
601/*
602 * acpi_coresight_parse_link	- Parse the given Graph connection
603 * of the device and populate the coresight_connection for an output
604 * connection.
605 *
606 * CoreSight Graph specification mandates that the direction of the data
607 * flow must be specified in the link. i.e,
608 *
609 *	SourcePortAddress,	// Integer
610 *	DestinationPortAddress,	// Integer
611 *	DestinationDeviceName,	// Reference to another device
612 *	DirectionOfFlow,	// 1 for output(master), 0 for input(slave)
613 *
614 * Returns the direction of the data flow [ Input(slave) or Output(master) ]
615 * upon success.
616 * Returns an negative error number otherwise.
617 */
618static int acpi_coresight_parse_link(struct acpi_device *adev,
619				     const union acpi_object *link,
620				     struct coresight_connection *conn)
621{
622	int rc, dir;
623	const union acpi_object *fields;
624	struct acpi_device *r_adev;
625	struct device *rdev;
626
627	if (link->type != ACPI_TYPE_PACKAGE ||
628	    link->package.count != 4)
629		return -EINVAL;
630
631	fields = link->package.elements;
632
633	if (fields[0].type != ACPI_TYPE_INTEGER ||
634	    fields[1].type != ACPI_TYPE_INTEGER ||
635	    fields[2].type != ACPI_TYPE_LOCAL_REFERENCE ||
636	    fields[3].type != ACPI_TYPE_INTEGER)
637		return -EINVAL;
638
639	rc = acpi_bus_get_device(fields[2].reference.handle, &r_adev);
640	if (rc)
641		return rc;
642
643	dir = fields[3].integer.value;
644	if (dir == ACPI_CORESIGHT_LINK_MASTER) {
645		conn->outport = fields[0].integer.value;
646		conn->child_port = fields[1].integer.value;
647		rdev = coresight_find_device_by_fwnode(&r_adev->fwnode);
648		if (!rdev)
649			return -EPROBE_DEFER;
650		/*
651		 * Hold the refcount to the target device. This could be
652		 * released via:
653		 * 1) coresight_release_platform_data() if the probe fails or
654		 *    this device is unregistered.
655		 * 2) While removing the target device via
656		 *    coresight_remove_match().
657		 */
658		conn->child_fwnode = fwnode_handle_get(&r_adev->fwnode);
659	} else if (dir == ACPI_CORESIGHT_LINK_SLAVE) {
660		/*
661		 * We are only interested in the port number
662		 * for the input ports at this component.
663		 * Store the port number in child_port.
664		 */
665		conn->child_port = fields[0].integer.value;
666	} else {
667		/* Invalid direction */
668		return -EINVAL;
669	}
670
671	return dir;
672}
673
674/*
675 * acpi_coresight_parse_graph	- Parse the _DSD CoreSight graph
676 * connection information and populate the supplied coresight_platform_data
677 * instance.
678 */
679static int acpi_coresight_parse_graph(struct acpi_device *adev,
680				      struct coresight_platform_data *pdata)
681{
682	int rc, i, nlinks;
683	const union acpi_object *graph;
684	struct coresight_connection *conns, *ptr;
685
686	pdata->nr_inport = pdata->nr_outport = 0;
687	graph = acpi_get_coresight_graph(adev);
688	if (!graph)
689		return -ENOENT;
690
691	nlinks = graph->package.elements[2].integer.value;
692	if (!nlinks)
693		return 0;
694
695	/*
696	 * To avoid scanning the table twice (once for finding the number of
697	 * output links and then later for parsing the output links),
698	 * cache the links information in one go and then later copy
699	 * it to the pdata.
700	 */
701	conns = devm_kcalloc(&adev->dev, nlinks, sizeof(*conns), GFP_KERNEL);
702	if (!conns)
703		return -ENOMEM;
704	ptr = conns;
705	for (i = 0; i < nlinks; i++) {
706		const union acpi_object *link = &graph->package.elements[3 + i];
707		int dir;
708
709		dir = acpi_coresight_parse_link(adev, link, ptr);
710		if (dir < 0)
711			return dir;
712
713		if (dir == ACPI_CORESIGHT_LINK_MASTER) {
714			if (ptr->outport > pdata->nr_outport)
715				pdata->nr_outport = ptr->outport;
716			ptr++;
717		} else {
718			WARN_ON(pdata->nr_inport == ptr->child_port);
719			/*
720			 * We do not track input port connections for a device.
721			 * However we need the highest port number described,
722			 * which can be recorded now and reuse this connection
723			 * record for an output connection. Hence, do not move
724			 * the ptr for input connections
725			 */
726			if (ptr->child_port > pdata->nr_inport)
727				pdata->nr_inport = ptr->child_port;
728		}
729	}
730
731	rc = coresight_alloc_conns(&adev->dev, pdata);
732	if (rc)
733		return rc;
734
735	/* Copy the connection information to the final location */
736	for (i = 0; conns + i < ptr; i++) {
737		int port = conns[i].outport;
738
739		/* Duplicate output port */
740		WARN_ON(pdata->conns[port].child_fwnode);
741		pdata->conns[port] = conns[i];
742	}
743
744	devm_kfree(&adev->dev, conns);
745	return 0;
746}
747
748/*
749 * acpi_handle_to_logical_cpuid - Map a given acpi_handle to the
750 * logical CPU id of the corresponding CPU device.
751 *
752 * Returns the logical CPU id when found. Otherwise returns >= nr_cpus_id.
753 */
754static int
755acpi_handle_to_logical_cpuid(acpi_handle handle)
756{
757	int i;
758	struct acpi_processor *pr;
759
760	for_each_possible_cpu(i) {
761		pr = per_cpu(processors, i);
762		if (pr && pr->handle == handle)
763			break;
764	}
765
766	return i;
767}
768
769/*
770 * acpi_coresigh_get_cpu - Find the logical CPU id of the CPU associated
771 * with this coresight device. With ACPI bindings, the CoreSight components
772 * are listed as child device of the associated CPU.
773 *
774 * Returns the logical CPU id when found. Otherwise returns 0.
775 */
776static int acpi_coresight_get_cpu(struct device *dev)
777{
778	int cpu;
779	acpi_handle cpu_handle;
780	acpi_status status;
781	struct acpi_device *adev = ACPI_COMPANION(dev);
782
783	if (!adev)
784		return -ENODEV;
785	status = acpi_get_parent(adev->handle, &cpu_handle);
786	if (ACPI_FAILURE(status))
787		return -ENODEV;
788
789	cpu = acpi_handle_to_logical_cpuid(cpu_handle);
790	if (cpu >= nr_cpu_ids)
791		return -ENODEV;
792	return cpu;
793}
794
795static int
796acpi_get_coresight_platform_data(struct device *dev,
797				 struct coresight_platform_data *pdata)
798{
799	struct acpi_device *adev;
800
801	adev = ACPI_COMPANION(dev);
802	if (!adev)
803		return -EINVAL;
804
805	return acpi_coresight_parse_graph(adev, pdata);
806}
807
808#else
809
810static inline int
811acpi_get_coresight_platform_data(struct device *dev,
812				 struct coresight_platform_data *pdata)
813{
814	return -ENOENT;
815}
816
817static inline int acpi_coresight_get_cpu(struct device *dev)
818{
819	return -ENODEV;
820}
821#endif
822
823int coresight_get_cpu(struct device *dev)
824{
825	if (is_of_node(dev->fwnode))
826		return of_coresight_get_cpu(dev);
827	else if (is_acpi_device_node(dev->fwnode))
828		return acpi_coresight_get_cpu(dev);
829	return 0;
830}
831EXPORT_SYMBOL_GPL(coresight_get_cpu);
832
833struct coresight_platform_data *
834coresight_get_platform_data(struct device *dev)
835{
836	int ret = -ENOENT;
837	struct coresight_platform_data *pdata = NULL;
838	struct fwnode_handle *fwnode = dev_fwnode(dev);
839
840	if (IS_ERR_OR_NULL(fwnode))
841		goto error;
842
843	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
844	if (!pdata) {
845		ret = -ENOMEM;
846		goto error;
847	}
848
849	if (is_of_node(fwnode))
850		ret = of_get_coresight_platform_data(dev, pdata);
851	else if (is_acpi_device_node(fwnode))
852		ret = acpi_get_coresight_platform_data(dev, pdata);
853
854	if (!ret)
855		return pdata;
856error:
857	if (!IS_ERR_OR_NULL(pdata))
858		/* Cleanup the connection information */
859		coresight_release_platform_data(NULL, pdata);
860	return ERR_PTR(ret);
861}
862EXPORT_SYMBOL_GPL(coresight_get_platform_data);