drivers/hwtracing/intel_th/core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Intel(R) Trace Hub driver core
   4  *
   5  * Copyright (C) 2014-2015 Intel Corporation.
   6  */
   7
   8 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/types.h>
  11 #include <linux/module.h>
  12 #include <linux/device.h>
  13 #include <linux/sysfs.h>
  14 #include <linux/kdev_t.h>
  15 #include <linux/debugfs.h>
  16 #include <linux/idr.h>
  17 #include <linux/pci.h>
  18 #include <linux/pm_runtime.h>
  19 #include <linux/dma-mapping.h>
  20
  21 #include "intel_th.h"
  22 #include "debug.h"
  23
  24 static bool host_mode __read_mostly;
  25 module_param(host_mode, bool, 0444);
  26
  27 static DEFINE_IDA(intel_th_ida);
  28
  29 static int intel_th_match(struct device *dev, struct device_driver *driver)
  30 {
  31         struct intel_th_driver *thdrv = to_intel_th_driver(driver);
  32         struct intel_th_device *thdev = to_intel_th_device(dev);
  33
  34         if (thdev->type == INTEL_TH_SWITCH &&
  35             (!thdrv->enable || !thdrv->disable))
  36                 return 0;
  37
  38         return !strcmp(thdev->name, driver->name);
  39 }
  40
  41 static int intel_th_child_remove(struct device *dev, void *data)
  42 {
  43         device_release_driver(dev);
  44
  45         return 0;
  46 }
  47
  48 static int intel_th_probe(struct device *dev)
  49 {
  50         struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
  51         struct intel_th_device *thdev = to_intel_th_device(dev);
  52         struct intel_th_driver *hubdrv;
  53         struct intel_th_device *hub = NULL;
  54         int ret;
  55
  56         if (thdev->type == INTEL_TH_SWITCH)
  57                 hub = thdev;
  58         else if (dev->parent)
  59                 hub = to_intel_th_device(dev->parent);
  60
  61         if (!hub || !hub->dev.driver)
  62                 return -EPROBE_DEFER;
  63
  64         hubdrv = to_intel_th_driver(hub->dev.driver);
  65
  66         pm_runtime_set_active(dev);
  67         pm_runtime_no_callbacks(dev);
  68         pm_runtime_enable(dev);
  69
  70         ret = thdrv->probe(to_intel_th_device(dev));
  71         if (ret)
  72                 goto out_pm;
  73
  74         if (thdrv->attr_group) {
  75                 ret = sysfs_create_group(&thdev->dev.kobj, thdrv->attr_group);
  76                 if (ret)
  77                         goto out;
  78         }
  79
  80         if (thdev->type == INTEL_TH_OUTPUT &&
  81             !intel_th_output_assigned(thdev))
  82                 /* does not talk to hardware */
  83                 ret = hubdrv->assign(hub, thdev);
  84
  85 out:
  86         if (ret)
  87                 thdrv->remove(thdev);
  88
  89 out_pm:
  90         if (ret)
  91                 pm_runtime_disable(dev);
  92
  93         return ret;
  94 }
  95
  96 static void intel_th_device_remove(struct intel_th_device *thdev);
  97
  98 static int intel_th_remove(struct device *dev)
  99 {
 100         struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
 101         struct intel_th_device *thdev = to_intel_th_device(dev);
 102         struct intel_th_device *hub = to_intel_th_hub(thdev);
 103         int err;
 104
 105         if (thdev->type == INTEL_TH_SWITCH) {
 106                 struct intel_th *th = to_intel_th(hub);
 107                 int i, lowest;
 108
 109                 /* disconnect outputs */
 110                 err = device_for_each_child(dev, thdev, intel_th_child_remove);
 111                 if (err)
 112                         return err;
 113
 114                 /*
 115                  * Remove outputs, that is, hub's children: they are created
 116                  * at hub's probe time by having the hub call
 117                  * intel_th_output_enable() for each of them.
 118                  */
 119                 for (i = 0, lowest = -1; i < th->num_thdevs; i++) {
 120                         /*
 121                          * Move the non-output devices from higher up the
 122                          * th->thdev[] array to lower positions to maintain
 123                          * a contiguous array.
 124                          */
 125                         if (th->thdev[i]->type != INTEL_TH_OUTPUT) {
 126                                 if (lowest >= 0) {
 127                                         th->thdev[lowest] = th->thdev[i];
 128                                         th->thdev[i] = NULL;
 129                                         ++lowest;
 130                                 }
 131
 132                                 continue;
 133                         }
 134
 135                         if (lowest == -1)
 136                                 lowest = i;
 137
 138                         intel_th_device_remove(th->thdev[i]);
 139                         th->thdev[i] = NULL;
 140                 }
 141
 142                 if (lowest >= 0)
 143                         th->num_thdevs = lowest;
 144         }
 145
 146         if (thdrv->attr_group)
 147                 sysfs_remove_group(&thdev->dev.kobj, thdrv->attr_group);
 148
 149         pm_runtime_get_sync(dev);
 150
 151         thdrv->remove(thdev);
 152
 153         if (intel_th_output_assigned(thdev)) {
 154                 struct intel_th_driver *hubdrv =
 155                         to_intel_th_driver(dev->parent->driver);
 156
 157                 if (hub->dev.driver)
 158                         /* does not talk to hardware */
 159                         hubdrv->unassign(hub, thdev);
 160         }
 161
 162         pm_runtime_disable(dev);
 163         pm_runtime_set_active(dev);
 164         pm_runtime_enable(dev);
 165
 166         return 0;
 167 }
 168
 169 static struct bus_type intel_th_bus = {
 170         .name           = "intel_th",
 171         .match          = intel_th_match,
 172         .probe          = intel_th_probe,
 173         .remove         = intel_th_remove,
 174 };
 175
 176 static void intel_th_device_free(struct intel_th_device *thdev);
 177
 178 static void intel_th_device_release(struct device *dev)
 179 {
 180         intel_th_device_free(to_intel_th_device(dev));
 181 }
 182
 183 static struct device_type intel_th_source_device_type = {
 184         .name           = "intel_th_source_device",
 185         .release        = intel_th_device_release,
 186 };
 187
 188 static char *intel_th_output_devnode(struct device *dev, umode_t *mode,
 189                                      kuid_t *uid, kgid_t *gid)
 190 {
 191         struct intel_th_device *thdev = to_intel_th_device(dev);
 192         struct intel_th *th = to_intel_th(thdev);
 193         char *node;
 194
 195         if (thdev->id >= 0)
 196                 node = kasprintf(GFP_KERNEL, "intel_th%d/%s%d", th->id,
 197                                  thdev->name, thdev->id);
 198         else
 199                 node = kasprintf(GFP_KERNEL, "intel_th%d/%s", th->id,
 200                                  thdev->name);
 201
 202         return node;
 203 }
 204
 205 static ssize_t port_show(struct device *dev, struct device_attribute *attr,
 206                          char *buf)
 207 {
 208         struct intel_th_device *thdev = to_intel_th_device(dev);
 209
 210         if (thdev->output.port >= 0)
 211                 return scnprintf(buf, PAGE_SIZE, "%u\n", thdev->output.port);
 212
 213         return scnprintf(buf, PAGE_SIZE, "unassigned\n");
 214 }
 215
 216 static DEVICE_ATTR_RO(port);
 217
 218 static void intel_th_trace_prepare(struct intel_th_device *thdev)
 219 {
 220         struct intel_th_device *hub = to_intel_th_hub(thdev);
 221         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 222
 223         if (hub->type != INTEL_TH_SWITCH)
 224                 return;
 225
 226         if (thdev->type != INTEL_TH_OUTPUT)
 227                 return;
 228
 229         pm_runtime_get_sync(&thdev->dev);
 230         hubdrv->prepare(hub, &thdev->output);
 231         pm_runtime_put(&thdev->dev);
 232 }
 233
 234 static int intel_th_output_activate(struct intel_th_device *thdev)
 235 {
 236         struct intel_th_driver *thdrv =
 237                 to_intel_th_driver_or_null(thdev->dev.driver);
 238         struct intel_th *th = to_intel_th(thdev);
 239         int ret = 0;
 240
 241         if (!thdrv)
 242                 return -ENODEV;
 243
 244         if (!try_module_get(thdrv->driver.owner))
 245                 return -ENODEV;
 246
 247         pm_runtime_get_sync(&thdev->dev);
 248
 249         if (th->activate)
 250                 ret = th->activate(th);
 251         if (ret)
 252                 goto fail_put;
 253
 254         intel_th_trace_prepare(thdev);
 255         if (thdrv->activate)
 256                 ret = thdrv->activate(thdev);
 257         else
 258                 intel_th_trace_enable(thdev);
 259
 260         if (ret)
 261                 goto fail_deactivate;
 262
 263         return 0;
 264
 265 fail_deactivate:
 266         if (th->deactivate)
 267                 th->deactivate(th);
 268
 269 fail_put:
 270         pm_runtime_put(&thdev->dev);
 271         module_put(thdrv->driver.owner);
 272
 273         return ret;
 274 }
 275
 276 static void intel_th_output_deactivate(struct intel_th_device *thdev)
 277 {
 278         struct intel_th_driver *thdrv =
 279                 to_intel_th_driver_or_null(thdev->dev.driver);
 280         struct intel_th *th = to_intel_th(thdev);
 281
 282         if (!thdrv)
 283                 return;
 284
 285         if (thdrv->deactivate)
 286                 thdrv->deactivate(thdev);
 287         else
 288                 intel_th_trace_disable(thdev);
 289
 290         if (th->deactivate)
 291                 th->deactivate(th);
 292
 293         pm_runtime_put(&thdev->dev);
 294         module_put(thdrv->driver.owner);
 295 }
 296
 297 static ssize_t active_show(struct device *dev, struct device_attribute *attr,
 298                            char *buf)
 299 {
 300         struct intel_th_device *thdev = to_intel_th_device(dev);
 301
 302         return scnprintf(buf, PAGE_SIZE, "%d\n", thdev->output.active);
 303 }
 304
 305 static ssize_t active_store(struct device *dev, struct device_attribute *attr,
 306                             const char *buf, size_t size)
 307 {
 308         struct intel_th_device *thdev = to_intel_th_device(dev);
 309         unsigned long val;
 310         int ret;
 311
 312         ret = kstrtoul(buf, 10, &val);
 313         if (ret)
 314                 return ret;
 315
 316         if (!!val != thdev->output.active) {
 317                 if (val)
 318                         ret = intel_th_output_activate(thdev);
 319                 else
 320                         intel_th_output_deactivate(thdev);
 321         }
 322
 323         return ret ? ret : size;
 324 }
 325
 326 static DEVICE_ATTR_RW(active);
 327
 328 static struct attribute *intel_th_output_attrs[] = {
 329         &dev_attr_port.attr,
 330         &dev_attr_active.attr,
 331         NULL,
 332 };
 333
 334 ATTRIBUTE_GROUPS(intel_th_output);
 335
 336 static struct device_type intel_th_output_device_type = {
 337         .name           = "intel_th_output_device",
 338         .groups         = intel_th_output_groups,
 339         .release        = intel_th_device_release,
 340         .devnode        = intel_th_output_devnode,
 341 };
 342
 343 static struct device_type intel_th_switch_device_type = {
 344         .name           = "intel_th_switch_device",
 345         .release        = intel_th_device_release,
 346 };
 347
 348 static struct device_type *intel_th_device_type[] = {
 349         [INTEL_TH_SOURCE]       = &intel_th_source_device_type,
 350         [INTEL_TH_OUTPUT]       = &intel_th_output_device_type,
 351         [INTEL_TH_SWITCH]       = &intel_th_switch_device_type,
 352 };
 353
 354 int intel_th_driver_register(struct intel_th_driver *thdrv)
 355 {
 356         if (!thdrv->probe || !thdrv->remove)
 357                 return -EINVAL;
 358
 359         thdrv->driver.bus = &intel_th_bus;
 360
 361         return driver_register(&thdrv->driver);
 362 }
 363 EXPORT_SYMBOL_GPL(intel_th_driver_register);
 364
 365 void intel_th_driver_unregister(struct intel_th_driver *thdrv)
 366 {
 367         driver_unregister(&thdrv->driver);
 368 }
 369 EXPORT_SYMBOL_GPL(intel_th_driver_unregister);
 370
 371 static struct intel_th_device *
 372 intel_th_device_alloc(struct intel_th *th, unsigned int type, const char *name,
 373                       int id)
 374 {
 375         struct device *parent;
 376         struct intel_th_device *thdev;
 377
 378         if (type == INTEL_TH_OUTPUT)
 379                 parent = &th->hub->dev;
 380         else
 381                 parent = th->dev;
 382
 383         thdev = kzalloc(sizeof(*thdev) + strlen(name) + 1, GFP_KERNEL);
 384         if (!thdev)
 385                 return NULL;
 386
 387         thdev->id = id;
 388         thdev->type = type;
 389
 390         strcpy(thdev->name, name);
 391         device_initialize(&thdev->dev);
 392         thdev->dev.bus = &intel_th_bus;
 393         thdev->dev.type = intel_th_device_type[type];
 394         thdev->dev.parent = parent;
 395         thdev->dev.dma_mask = parent->dma_mask;
 396         thdev->dev.dma_parms = parent->dma_parms;
 397         dma_set_coherent_mask(&thdev->dev, parent->coherent_dma_mask);
 398         if (id >= 0)
 399                 dev_set_name(&thdev->dev, "%d-%s%d", th->id, name, id);
 400         else
 401                 dev_set_name(&thdev->dev, "%d-%s", th->id, name);
 402
 403         return thdev;
 404 }
 405
 406 static int intel_th_device_add_resources(struct intel_th_device *thdev,
 407                                          struct resource *res, int nres)
 408 {
 409         struct resource *r;
 410
 411         r = kmemdup(res, sizeof(*res) * nres, GFP_KERNEL);
 412         if (!r)
 413                 return -ENOMEM;
 414
 415         thdev->resource = r;
 416         thdev->num_resources = nres;
 417
 418         return 0;
 419 }
 420
 421 static void intel_th_device_remove(struct intel_th_device *thdev)
 422 {
 423         device_del(&thdev->dev);
 424         put_device(&thdev->dev);
 425 }
 426
 427 static void intel_th_device_free(struct intel_th_device *thdev)
 428 {
 429         kfree(thdev->resource);
 430         kfree(thdev);
 431 }
 432
 433 /*
 434  * Intel(R) Trace Hub subdevices
 435  */
 436 static const struct intel_th_subdevice {
 437         const char              *name;
 438         struct resource         res[3];
 439         unsigned                nres;
 440         unsigned                type;
 441         unsigned                otype;
 442         unsigned                scrpd;
 443         int                     id;
 444 } intel_th_subdevices[] = {
 445         {
 446                 .nres   = 1,
 447                 .res    = {
 448                         {
 449                                 /* Handle TSCU from GTH driver */
 450                                 .start  = REG_GTH_OFFSET,
 451                                 .end    = REG_TSCU_OFFSET + REG_TSCU_LENGTH - 1,
 452                                 .flags  = IORESOURCE_MEM,
 453                         },
 454                 },
 455                 .name   = "gth",
 456                 .type   = INTEL_TH_SWITCH,
 457                 .id     = -1,
 458         },
 459         {
 460                 .nres   = 2,
 461                 .res    = {
 462                         {
 463                                 .start  = REG_MSU_OFFSET,
 464                                 .end    = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 465                                 .flags  = IORESOURCE_MEM,
 466                         },
 467                         {
 468                                 .start  = BUF_MSU_OFFSET,
 469                                 .end    = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 470                                 .flags  = IORESOURCE_MEM,
 471                         },
 472                 },
 473                 .name   = "msc",
 474                 .id     = 0,
 475                 .type   = INTEL_TH_OUTPUT,
 476                 .otype  = GTH_MSU,
 477                 .scrpd  = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC0_IS_ENABLED,
 478         },
 479         {
 480                 .nres   = 2,
 481                 .res    = {
 482                         {
 483                                 .start  = REG_MSU_OFFSET,
 484                                 .end    = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 485                                 .flags  = IORESOURCE_MEM,
 486                         },
 487                         {
 488                                 .start  = BUF_MSU_OFFSET,
 489                                 .end    = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 490                                 .flags  = IORESOURCE_MEM,
 491                         },
 492                 },
 493                 .name   = "msc",
 494                 .id     = 1,
 495                 .type   = INTEL_TH_OUTPUT,
 496                 .otype  = GTH_MSU,
 497                 .scrpd  = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC1_IS_ENABLED,
 498         },
 499         {
 500                 .nres   = 2,
 501                 .res    = {
 502                         {
 503                                 .start  = REG_STH_OFFSET,
 504                                 .end    = REG_STH_OFFSET + REG_STH_LENGTH - 1,
 505                                 .flags  = IORESOURCE_MEM,
 506                         },
 507                         {
 508                                 .start  = 1, /* use resource[1] */
 509                                 .end    = 0,
 510                                 .flags  = IORESOURCE_MEM,
 511                         },
 512                 },
 513                 .id     = -1,
 514                 .name   = "sth",
 515                 .type   = INTEL_TH_SOURCE,
 516         },
 517         {
 518                 .nres   = 1,
 519                 .res    = {
 520                         {
 521                                 .start  = REG_PTI_OFFSET,
 522                                 .end    = REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
 523                                 .flags  = IORESOURCE_MEM,
 524                         },
 525                 },
 526                 .id     = -1,
 527                 .name   = "pti",
 528                 .type   = INTEL_TH_OUTPUT,
 529                 .otype  = GTH_PTI,
 530                 .scrpd  = SCRPD_PTI_IS_PRIM_DEST,
 531         },
 532         {
 533                 .nres   = 1,
 534                 .res    = {
 535                         {
 536                                 .start  = REG_PTI_OFFSET,
 537                                 .end    = REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
 538                                 .flags  = IORESOURCE_MEM,
 539                         },
 540                 },
 541                 .id     = -1,
 542                 .name   = "lpp",
 543                 .type   = INTEL_TH_OUTPUT,
 544                 .otype  = GTH_LPP,
 545                 .scrpd  = SCRPD_PTI_IS_PRIM_DEST,
 546         },
 547         {
 548                 .nres   = 1,
 549                 .res    = {
 550                         {
 551                                 .start  = REG_DCIH_OFFSET,
 552                                 .end    = REG_DCIH_OFFSET + REG_DCIH_LENGTH - 1,
 553                                 .flags  = IORESOURCE_MEM,
 554                         },
 555                 },
 556                 .id     = -1,
 557                 .name   = "dcih",
 558                 .type   = INTEL_TH_OUTPUT,
 559         },
 560 };
 561
 562 #ifdef CONFIG_MODULES
 563 static void __intel_th_request_hub_module(struct work_struct *work)
 564 {
 565         struct intel_th *th = container_of(work, struct intel_th,
 566                                            request_module_work);
 567
 568         request_module("intel_th_%s", th->hub->name);
 569 }
 570
 571 static int intel_th_request_hub_module(struct intel_th *th)
 572 {
 573         INIT_WORK(&th->request_module_work, __intel_th_request_hub_module);
 574         schedule_work(&th->request_module_work);
 575
 576         return 0;
 577 }
 578
 579 static void intel_th_request_hub_module_flush(struct intel_th *th)
 580 {
 581         flush_work(&th->request_module_work);
 582 }
 583 #else
 584 static inline int intel_th_request_hub_module(struct intel_th *th)
 585 {
 586         return -EINVAL;
 587 }
 588
 589 static inline void intel_th_request_hub_module_flush(struct intel_th *th)
 590 {
 591 }
 592 #endif /* CONFIG_MODULES */
 593
 594 static struct intel_th_device *
 595 intel_th_subdevice_alloc(struct intel_th *th,
 596                          const struct intel_th_subdevice *subdev)
 597 {
 598         struct intel_th_device *thdev;
 599         struct resource res[3];
 600         unsigned int req = 0;
 601         bool is64bit = false;
 602         int r, err;
 603
 604         thdev = intel_th_device_alloc(th, subdev->type, subdev->name,
 605                                       subdev->id);
 606         if (!thdev)
 607                 return ERR_PTR(-ENOMEM);
 608
 609         thdev->drvdata = th->drvdata;
 610
 611         for (r = 0; r < th->num_resources; r++)
 612                 if (th->resource[r].flags & IORESOURCE_MEM_64) {
 613                         is64bit = true;
 614                         break;
 615                 }
 616
 617         memcpy(res, subdev->res,
 618                sizeof(struct resource) * subdev->nres);
 619
 620         for (r = 0; r < subdev->nres; r++) {
 621                 struct resource *devres = th->resource;
 622                 int bar = 0; /* cut subdevices' MMIO from resource[0] */
 623
 624                 /*
 625                  * Take .end == 0 to mean 'take the whole bar',
 626                  * .start then tells us which bar it is. Default to
 627                  * TH_MMIO_CONFIG.
 628                  */
 629                 if (!res[r].end && res[r].flags == IORESOURCE_MEM) {
 630                         bar = res[r].start;
 631                         if (is64bit)
 632                                 bar *= 2;
 633                         res[r].start = 0;
 634                         res[r].end = resource_size(&devres[bar]) - 1;
 635                 }
 636
 637                 if (res[r].flags & IORESOURCE_MEM) {
 638                         res[r].start    += devres[bar].start;
 639                         res[r].end      += devres[bar].start;
 640
 641                         dev_dbg(th->dev, "%s:%d @ %pR\n",
 642                                 subdev->name, r, &res[r]);
 643                 } else if (res[r].flags & IORESOURCE_IRQ) {
 644                         res[r].start    = th->irq;
 645                 }
 646         }
 647
 648         err = intel_th_device_add_resources(thdev, res, subdev->nres);
 649         if (err)
 650                 goto fail_put_device;
 651
 652         if (subdev->type == INTEL_TH_OUTPUT) {
 653                 thdev->dev.devt = MKDEV(th->major, th->num_thdevs);
 654                 thdev->output.type = subdev->otype;
 655                 thdev->output.port = -1;
 656                 thdev->output.scratchpad = subdev->scrpd;
 657         } else if (subdev->type == INTEL_TH_SWITCH) {
 658                 thdev->host_mode =
 659                         INTEL_TH_CAP(th, host_mode_only) ? true : host_mode;
 660                 th->hub = thdev;
 661         }
 662
 663         err = device_add(&thdev->dev);
 664         if (err)
 665                 goto fail_free_res;
 666
 667         /* need switch driver to be loaded to enumerate the rest */
 668         if (subdev->type == INTEL_TH_SWITCH && !req) {
 669                 err = intel_th_request_hub_module(th);
 670                 if (!err)
 671                         req++;
 672         }
 673
 674         return thdev;
 675
 676 fail_free_res:
 677         kfree(thdev->resource);
 678
 679 fail_put_device:
 680         put_device(&thdev->dev);
 681
 682         return ERR_PTR(err);
 683 }
 684
 685 /**
 686  * intel_th_output_enable() - find and enable a device for a given output type
 687  * @th:         Intel TH instance
 688  * @otype:      output type
 689  *
 690  * Go through the unallocated output devices, find the first one whos type
 691  * matches @otype and instantiate it. These devices are removed when the hub
 692  * device is removed, see intel_th_remove().
 693  */
 694 int intel_th_output_enable(struct intel_th *th, unsigned int otype)
 695 {
 696         struct intel_th_device *thdev;
 697         int src = 0, dst = 0;
 698
 699         for (src = 0, dst = 0; dst <= th->num_thdevs; src++, dst++) {
 700                 for (; src < ARRAY_SIZE(intel_th_subdevices); src++) {
 701                         if (intel_th_subdevices[src].type != INTEL_TH_OUTPUT)
 702                                 continue;
 703
 704                         if (intel_th_subdevices[src].otype != otype)
 705                                 continue;
 706
 707                         break;
 708                 }
 709
 710                 /* no unallocated matching subdevices */
 711                 if (src == ARRAY_SIZE(intel_th_subdevices))
 712                         return -ENODEV;
 713
 714                 for (; dst < th->num_thdevs; dst++) {
 715                         if (th->thdev[dst]->type != INTEL_TH_OUTPUT)
 716                                 continue;
 717
 718                         if (th->thdev[dst]->output.type != otype)
 719                                 continue;
 720
 721                         break;
 722                 }
 723
 724                 /*
 725                  * intel_th_subdevices[src] matches our requirements and is
 726                  * not matched in th::thdev[]
 727                  */
 728                 if (dst == th->num_thdevs)
 729                         goto found;
 730         }
 731
 732         return -ENODEV;
 733
 734 found:
 735         thdev = intel_th_subdevice_alloc(th, &intel_th_subdevices[src]);
 736         if (IS_ERR(thdev))
 737                 return PTR_ERR(thdev);
 738
 739         th->thdev[th->num_thdevs++] = thdev;
 740
 741         return 0;
 742 }
 743 EXPORT_SYMBOL_GPL(intel_th_output_enable);
 744
 745 static int intel_th_populate(struct intel_th *th)
 746 {
 747         int src;
 748
 749         /* create devices for each intel_th_subdevice */
 750         for (src = 0; src < ARRAY_SIZE(intel_th_subdevices); src++) {
 751                 const struct intel_th_subdevice *subdev =
 752                         &intel_th_subdevices[src];
 753                 struct intel_th_device *thdev;
 754
 755                 /* only allow SOURCE and SWITCH devices in host mode */
 756                 if ((INTEL_TH_CAP(th, host_mode_only) || host_mode) &&
 757                     subdev->type == INTEL_TH_OUTPUT)
 758                         continue;
 759
 760                 /*
 761                  * don't enable port OUTPUTs in this path; SWITCH enables them
 762                  * via intel_th_output_enable()
 763                  */
 764                 if (subdev->type == INTEL_TH_OUTPUT &&
 765                     subdev->otype != GTH_NONE)
 766                         continue;
 767
 768                 thdev = intel_th_subdevice_alloc(th, subdev);
 769                 /* note: caller should free subdevices from th::thdev[] */
 770                 if (IS_ERR(thdev))
 771                         return PTR_ERR(thdev);
 772
 773                 th->thdev[th->num_thdevs++] = thdev;
 774         }
 775
 776         return 0;
 777 }
 778
 779 static int match_devt(struct device *dev, void *data)
 780 {
 781         dev_t devt = (dev_t)(unsigned long)data;
 782
 783         return dev->devt == devt;
 784 }
 785
 786 static int intel_th_output_open(struct inode *inode, struct file *file)
 787 {
 788         const struct file_operations *fops;
 789         struct intel_th_driver *thdrv;
 790         struct device *dev;
 791         int err;
 792
 793         dev = bus_find_device(&intel_th_bus, NULL,
 794                               (void *)(unsigned long)inode->i_rdev,
 795                               match_devt);
 796         if (!dev || !dev->driver)
 797                 return -ENODEV;
 798
 799         thdrv = to_intel_th_driver(dev->driver);
 800         fops = fops_get(thdrv->fops);
 801         if (!fops)
 802                 return -ENODEV;
 803
 804         replace_fops(file, fops);
 805
 806         file->private_data = to_intel_th_device(dev);
 807
 808         if (file->f_op->open) {
 809                 err = file->f_op->open(inode, file);
 810                 return err;
 811         }
 812
 813         return 0;
 814 }
 815
 816 static const struct file_operations intel_th_output_fops = {
 817         .open   = intel_th_output_open,
 818         .llseek = noop_llseek,
 819 };
 820
 821 /**
 822  * intel_th_alloc() - allocate a new Intel TH device and its subdevices
 823  * @dev:        parent device
 824  * @devres:     parent's resources
 825  * @ndevres:    number of resources
 826  * @irq:        irq number
 827  */
 828 struct intel_th *
 829 intel_th_alloc(struct device *dev, struct intel_th_drvdata *drvdata,
 830                struct resource *devres, unsigned int ndevres, int irq)
 831 {
 832         struct intel_th *th;
 833         int err, r;
 834
 835         if (irq == -1)
 836                 for (r = 0; r < ndevres; r++)
 837                         if (devres[r].flags & IORESOURCE_IRQ) {
 838                                 irq = devres[r].start;
 839                                 break;
 840                         }
 841
 842         th = kzalloc(sizeof(*th), GFP_KERNEL);
 843         if (!th)
 844                 return ERR_PTR(-ENOMEM);
 845
 846         th->id = ida_simple_get(&intel_th_ida, 0, 0, GFP_KERNEL);
 847         if (th->id < 0) {
 848                 err = th->id;
 849                 goto err_alloc;
 850         }
 851
 852         th->major = __register_chrdev(0, 0, TH_POSSIBLE_OUTPUTS,
 853                                       "intel_th/output", &intel_th_output_fops);
 854         if (th->major < 0) {
 855                 err = th->major;
 856                 goto err_ida;
 857         }
 858         th->dev = dev;
 859         th->drvdata = drvdata;
 860
 861         th->resource = devres;
 862         th->num_resources = ndevres;
 863         th->irq = irq;
 864
 865         dev_set_drvdata(dev, th);
 866
 867         pm_runtime_no_callbacks(dev);
 868         pm_runtime_put(dev);
 869         pm_runtime_allow(dev);
 870
 871         err = intel_th_populate(th);
 872         if (err) {
 873                 /* free the subdevices and undo everything */
 874                 intel_th_free(th);
 875                 return ERR_PTR(err);
 876         }
 877
 878         return th;
 879
 880 err_ida:
 881         ida_simple_remove(&intel_th_ida, th->id);
 882
 883 err_alloc:
 884         kfree(th);
 885
 886         return ERR_PTR(err);
 887 }
 888 EXPORT_SYMBOL_GPL(intel_th_alloc);
 889
 890 void intel_th_free(struct intel_th *th)
 891 {
 892         int i;
 893
 894         intel_th_request_hub_module_flush(th);
 895
 896         intel_th_device_remove(th->hub);
 897         for (i = 0; i < th->num_thdevs; i++) {
 898                 if (th->thdev[i] != th->hub)
 899                         intel_th_device_remove(th->thdev[i]);
 900                 th->thdev[i] = NULL;
 901         }
 902
 903         th->num_thdevs = 0;
 904
 905         pm_runtime_get_sync(th->dev);
 906         pm_runtime_forbid(th->dev);
 907
 908         __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
 909                             "intel_th/output");
 910
 911         ida_simple_remove(&intel_th_ida, th->id);
 912
 913         kfree(th);
 914 }
 915 EXPORT_SYMBOL_GPL(intel_th_free);
 916
 917 /**
 918  * intel_th_trace_enable() - enable tracing for an output device
 919  * @thdev:      output device that requests tracing be enabled
 920  */
 921 int intel_th_trace_enable(struct intel_th_device *thdev)
 922 {
 923         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 924         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 925
 926         if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
 927                 return -EINVAL;
 928
 929         if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
 930                 return -EINVAL;
 931
 932         pm_runtime_get_sync(&thdev->dev);
 933         hubdrv->enable(hub, &thdev->output);
 934
 935         return 0;
 936 }
 937 EXPORT_SYMBOL_GPL(intel_th_trace_enable);
 938
 939 /**
 940  * intel_th_trace_disable() - disable tracing for an output device
 941  * @thdev:      output device that requests tracing be disabled
 942  */
 943 int intel_th_trace_disable(struct intel_th_device *thdev)
 944 {
 945         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 946         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 947
 948         WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH);
 949         if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
 950                 return -EINVAL;
 951
 952         hubdrv->disable(hub, &thdev->output);
 953         pm_runtime_put(&thdev->dev);
 954
 955         return 0;
 956 }
 957 EXPORT_SYMBOL_GPL(intel_th_trace_disable);
 958
 959 int intel_th_set_output(struct intel_th_device *thdev,
 960                         unsigned int master)
 961 {
 962         struct intel_th_device *hub = to_intel_th_hub(thdev);
 963         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 964         int ret;
 965
 966         /* In host mode, this is up to the external debugger, do nothing. */
 967         if (hub->host_mode)
 968                 return 0;
 969
 970         /*
 971          * hub is instantiated together with the source device that
 972          * calls here, so guaranteed to be present.
 973          */
 974         hubdrv = to_intel_th_driver(hub->dev.driver);
 975         if (!hubdrv || !try_module_get(hubdrv->driver.owner))
 976                 return -EINVAL;
 977
 978         if (!hubdrv->set_output) {
 979                 ret = -ENOTSUPP;
 980                 goto out;
 981         }
 982
 983         ret = hubdrv->set_output(hub, master);
 984
 985 out:
 986         module_put(hubdrv->driver.owner);
 987         return ret;
 988 }
 989 EXPORT_SYMBOL_GPL(intel_th_set_output);
 990
 991 static int __init intel_th_init(void)
 992 {
 993         intel_th_debug_init();
 994
 995         return bus_register(&intel_th_bus);
 996 }
 997 subsys_initcall(intel_th_init);
 998
 999 static void __exit intel_th_exit(void)
1000 {
1001         intel_th_debug_done();
1002
1003         bus_unregister(&intel_th_bus);
1004 }
1005 module_exit(intel_th_exit);
1006
1007 MODULE_LICENSE("GPL v2");
1008 MODULE_DESCRIPTION("Intel(R) Trace Hub controller driver");
1009 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");