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}
  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 rc, 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        rc = acpi_bus_get_device(fields[2].reference.handle, &r_adev);
 647        if (rc)
 648                return rc;
 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);
 870