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  */
26 struct coresight_connection *
coresight_add_out_conn(struct device * dev,struct coresight_platform_data * pdata,const struct coresight_connection * new_conn)27 coresight_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 }
69 EXPORT_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  */
coresight_add_in_conn(struct coresight_connection * out_conn)77 int 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 }
98 EXPORT_SYMBOL_GPL(coresight_add_in_conn);
99 
100 static struct device *
coresight_find_device_by_fwnode(struct fwnode_handle * fwnode)101 coresight_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  */
126 struct coresight_device *
coresight_find_csdev_by_fwnode(struct fwnode_handle * r_fwnode)127 coresight_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 }
139 EXPORT_SYMBOL_GPL(coresight_find_csdev_by_fwnode);
140 
141 #ifdef CONFIG_OF
of_coresight_legacy_ep_is_input(struct device_node * ep)142 static inline bool of_coresight_legacy_ep_is_input(struct device_node *ep)
143 {
144 	return of_property_read_bool(ep, "slave-mode");
145 }
146 
of_coresight_get_port_parent(struct device_node * ep)147 static 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 
162 static inline struct device_node *
of_coresight_get_output_ports_node(const struct device_node * node)163 of_coresight_get_output_ports_node(const struct device_node *node)
164 {
165 	return of_get_child_by_name(node, "out-ports");
166 }
167 
of_coresight_get_cpu(struct device * dev)168 static 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  */
of_coresight_parse_endpoint(struct device * dev,struct device_node * ep,struct coresight_platform_data * pdata)196 static int of_coresight_parse_endpoint(struct device *dev,
197 				       struct device_node *ep,
198 				       struct coresight_platform_data *pdata)
199 {
200 	int ret = 0;
201 	struct of_endpoint endpoint, rendpoint;
202 	struct device_node *rparent = NULL;
203 	struct device_node *rep = NULL;
204 	struct device *rdev = NULL;
205 	struct fwnode_handle *rdev_fwnode;
206 	struct coresight_connection conn = {};
207 	struct coresight_connection *new_conn;
208 
209 	do {
210 		/* Parse the local port details */
211 		if (of_graph_parse_endpoint(ep, &endpoint))
212 			break;
213 		/*
214 		 * Get a handle on the remote endpoint and the device it is
215 		 * attached to.
216 		 */
217 		rep = of_graph_get_remote_endpoint(ep);
218 		if (!rep)
219 			break;
220 		rparent = of_coresight_get_port_parent(rep);
221 		if (!rparent)
222 			break;
223 		if (of_graph_parse_endpoint(rep, &rendpoint))
224 			break;
225 
226 		rdev_fwnode = of_fwnode_handle(rparent);
227 		/* If the remote device is not available, defer probing */
228 		rdev = coresight_find_device_by_fwnode(rdev_fwnode);
229 		if (!rdev) {
230 			ret = -EPROBE_DEFER;
231 			break;
232 		}
233 
234 		conn.src_port = endpoint.port;
235 		/*
236 		 * Hold the refcount to the target device. This could be
237 		 * released via:
238 		 * 1) coresight_release_platform_data() if the probe fails or
239 		 *    this device is unregistered.
240 		 * 2) While removing the target device via
241 		 *    coresight_remove_match()
242 		 */
243 		conn.dest_fwnode = fwnode_handle_get(rdev_fwnode);
244 		conn.dest_port = rendpoint.port;
245 
246 		new_conn = coresight_add_out_conn(dev, pdata, &conn);
247 		if (IS_ERR_VALUE(new_conn)) {
248 			fwnode_handle_put(conn.dest_fwnode);
249 			return PTR_ERR(new_conn);
250 		}
251 		/* Connection record updated */
252 	} while (0);
253 
254 	of_node_put(rparent);
255 	of_node_put(rep);
256 	put_device(rdev);
257 
258 	return ret;
259 }
260 
of_get_coresight_platform_data(struct device * dev,struct coresight_platform_data * pdata)261 static int of_get_coresight_platform_data(struct device *dev,
262 					  struct coresight_platform_data *pdata)
263 {
264 	int ret = 0;
265 	struct device_node *ep = NULL;
266 	const struct device_node *parent = NULL;
267 	bool legacy_binding = false;
268 	struct device_node *node = dev->of_node;
269 
270 	parent = of_coresight_get_output_ports_node(node);
271 	/*
272 	 * If the DT uses obsoleted bindings, the ports are listed
273 	 * under the device and we need to filter out the input
274 	 * ports.
275 	 */
276 	if (!parent) {
277 		/*
278 		 * Avoid warnings in of_graph_get_next_endpoint()
279 		 * if the device doesn't have any graph connections
280 		 */
281 		if (!of_graph_is_present(node))
282 			return 0;
283 		legacy_binding = true;
284 		parent = node;
285 		dev_warn_once(dev, "Uses obsolete Coresight DT bindings\n");
286 	}
287 
288 	/* Iterate through each output port to discover topology */
289 	while ((ep = of_graph_get_next_endpoint(parent, ep))) {
290 		/*
291 		 * Legacy binding mixes input/output ports under the
292 		 * same parent. So, skip the input ports if we are dealing
293 		 * with legacy binding, as they processed with their
294 		 * connected output ports.
295 		 */
296 		if (legacy_binding && of_coresight_legacy_ep_is_input(ep))
297 			continue;
298 
299 		ret = of_coresight_parse_endpoint(dev, ep, pdata);
300 		if (ret) {
301 			of_node_put(ep);
302 			return ret;
303 		}
304 	}
305 
306 	return 0;
307 }
308 #else
309 static inline int
of_get_coresight_platform_data(struct device * dev,struct coresight_platform_data * pdata)310 of_get_coresight_platform_data(struct device *dev,
311 			       struct coresight_platform_data *pdata)
312 {
313 	return -ENOENT;
314 }
315 
of_coresight_get_cpu(struct device * dev)316 static inline int of_coresight_get_cpu(struct device *dev)
317 {
318 	return -ENODEV;
319 }
320 #endif
321 
322 #ifdef CONFIG_ACPI
323 
324 #include <acpi/actypes.h>
325 #include <acpi/processor.h>
326 
327 /* ACPI Graph _DSD UUID : "ab02a46b-74c7-45a2-bd68-f7d344ef2153" */
328 static 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" */
332 static 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	0
336 #define ACPI_CORESIGHT_LINK_MASTER	1
337 
is_acpi_guid(const union acpi_object * obj)338 static 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 and
345  * that it matches the supplied the GUID.
346  */
acpi_guid_matches(const union acpi_object * obj,const guid_t * guid)347 static 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 
is_acpi_dsd_graph_guid(const union acpi_object * obj)354 static inline bool is_acpi_dsd_graph_guid(const union acpi_object *obj)
355 {
356 	return acpi_guid_matches(obj, &acpi_graph_uuid);
357 }
358 
is_acpi_coresight_graph_guid(const union acpi_object * obj)359 static inline bool is_acpi_coresight_graph_guid(const union acpi_object *obj)
360 {
361 	return acpi_guid_matches(obj, &coresight_graph_uuid);
362 }
363 
is_acpi_coresight_graph(const union acpi_object * obj)364 static 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 conforms
385  * to the ACPI _DSD Graph specification.
386  *
387  * ACPI Devices Graph property has the following format:
388  *  {
389  *	Revision	- Integer, must be 0
390  *	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 governs
400  *			  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	- Integer
411  *	DestinationPortAddress	- Integer
412  *	DestinationDeviceName	- Reference to another device
413  *	( --- 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 device
420  *
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 UUID
427  *	Package() {
428  *		Package(2) { "property-name", <property-value> }
429  *	},
430  *
431  *	ToUUID("ab02a46b-74c7-45a2-bd68-f7d344ef2153"), // ACPI Graph UUID
432  *	Package() {
433  *	  0,		// Revision
434  *	  1,		// NumberOfGraphs.
435  *	  Package() {	// Graph[0] Package
436  *	     1,		// GraphID
437  *	     // Coresight Graph UUID
438  *	     ToUUID("3ecbc8b6-1d0e-4fb3-8107-e627f805c6cd"),
439  *	     3,		// NumberOfLinks aka ports
440  *	     // Link[0]: Output_0 -> Replicator:Input_0
441  *	     Package () { 0, 0, \_SB_.RPL0, 1 },
442  *	     // Link[1]: Input_0 <- Cluster0_Funnel0:Output_0
443  *	     Package () { 0, 0, \_SB_.CLU0.FUN0, 0 },
444  *	     // Link[2]: Input_1 <- Cluster1_Funnel0:Output_0
445  *	      Package () { 1, 0, \_SB_.CLU1.FUN0, 0 },
446  *	  }	// End of Graph[0] Package
447  *
448  *	}, // End of ACPI Graph Property
449  *  })
450  */
acpi_validate_dsd_graph(const union acpi_object * graph)451 static 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. */
496 static const union acpi_object *
acpi_get_dsd_graph(struct acpi_device * adev,struct acpi_buffer * buf)497 acpi_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 
535 static inline bool
acpi_validate_coresight_graph(const union acpi_object * cs_graph)536 acpi_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 find
553  * the Graph property matching the CoreSight Graphs.
554  *
555  * Returns the pointer to the CoreSight Graph Package when found. Otherwise
556  * returns NULL.
557  */
558 static const union acpi_object *
acpi_get_coresight_graph(struct acpi_device * adev,struct acpi_buffer * buf)559 acpi_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 connection
585  * of the device and populate the coresight_connection for an output
586  * connection.
587  *
588  * CoreSight Graph specification mandates that the direction of the data
589  * flow must be specified in the link. i.e,
590  *
591  *	SourcePortAddress,	// Integer
592  *	DestinationPortAddress,	// Integer
593  *	DestinationDeviceName,	// Reference to another device
594  *	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  */
acpi_coresight_parse_link(struct acpi_device * adev,const union acpi_object * link,struct coresight_connection * conn)600 static 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 be
634 		 * released via:
635 		 * 1) coresight_release_platform_data() if the probe fails or
636 		 *    this device is unregistered.
637 		 * 2) While removing the target device via
638 		 *    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 number
644 		 * 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 graph
658  * connection information and populate the supplied coresight_platform_data
659  * instance.
660  */
acpi_coresight_parse_graph(struct device * dev,struct acpi_device * adev,struct coresight_platform_data * pdata)661 static 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., ETE
676 	 */
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 
704 free:
705 	/*
706 	 * When ACPI fails to alloc a buffer, it will free the buffer
707 	 * 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 the
716  * logical CPU id of the corresponding CPU device.
717  *
718  * Returns the logical CPU id when found. Otherwise returns >= nr_cpus_id.
719  */
720 static int
acpi_handle_to_logical_cpuid(acpi_handle handle)721 acpi_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 associated
737  * with this coresight device. With ACPI bindings, the CoreSight components
738  * are listed as child device of the associated CPU.
739  *
740  * Returns the logical CPU id when found. Otherwise returns 0.
741  */
acpi_coresight_get_cpu(struct device * dev)742 static 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 
761 static int
acpi_get_coresight_platform_data(struct device * dev,struct coresight_platform_data * pdata)762 acpi_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 #else
775 
776 static inline int
acpi_get_coresight_platform_data(struct device * dev,struct coresight_platform_data * pdata)777 acpi_get_coresight_platform_data(struct device *dev,
778 				 struct coresight_platform_data *pdata)
779 {
780 	return -ENOENT;
781 }
782 
acpi_coresight_get_cpu(struct device * dev)783 static inline int acpi_coresight_get_cpu(struct device *dev)
784 {
785 	return -ENODEV;
786 }
787 #endif
788 
coresight_get_cpu(struct device * dev)789 int 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 }
797 EXPORT_SYMBOL_GPL(coresight_get_cpu);
798 
799 struct coresight_platform_data *
coresight_get_platform_data(struct device * dev)800 coresight_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;
822 error:
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 }
828 EXPORT_SYMBOL_GPL(coresight_get_platform_data);
829