linux/drivers/hwtracing/coresight/coresight-platform.c
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   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);
 863