root/drivers/hwtracing/coresight/coresight-platform.c

DEFINITIONS

1. coresight_alloc_conns
2. coresight_find_device_by_fwnode
3. of_coresight_legacy_ep_is_input
4. of_coresight_get_ports_legacy
5. of_coresight_get_port_parent
6. of_coresight_get_input_ports_node
7. of_coresight_get_output_ports_node
8. of_coresight_count_ports
9. of_coresight_get_ports
10. of_coresight_get_cpu
11. of_coresight_parse_endpoint
12. of_get_coresight_platform_data
13. of_get_coresight_platform_data
14. of_coresight_get_cpu
15. is_acpi_guid
16. acpi_guid_matches
17. is_acpi_dsd_graph_guid
18. is_acpi_coresight_graph_guid
19. is_acpi_coresight_graph
20. acpi_validate_dsd_graph
21. acpi_get_dsd_graph
22. acpi_validate_coresight_graph
23. acpi_get_coresight_graph
24. acpi_coresight_parse_link
25. acpi_coresight_parse_graph
26. acpi_handle_to_logical_cpuid
27. acpi_coresight_get_cpu
28. acpi_get_coresight_platform_data
29. acpi_get_coresight_platform_data
30. acpi_coresight_get_cpu
31. coresight_get_cpu
32. coresight_get_platform_data

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