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 int intel_th_output_activate(struct intel_th_device *thdev)
 219 {
 220         struct intel_th_driver *thdrv =
 221                 to_intel_th_driver_or_null(thdev->dev.driver);
 222         struct intel_th *th = to_intel_th(thdev);
 223         int ret = 0;
 224
 225         if (!thdrv)
 226                 return -ENODEV;
 227
 228         if (!try_module_get(thdrv->driver.owner))
 229                 return -ENODEV;
 230
 231         pm_runtime_get_sync(&thdev->dev);
 232
 233         if (th->activate)
 234                 ret = th->activate(th);
 235         if (ret)
 236                 goto fail_put;
 237
 238         if (thdrv->activate)
 239                 ret = thdrv->activate(thdev);
 240         else
 241                 intel_th_trace_enable(thdev);
 242
 243         if (ret)
 244                 goto fail_deactivate;
 245
 246         return 0;
 247
 248 fail_deactivate:
 249         if (th->deactivate)
 250                 th->deactivate(th);
 251
 252 fail_put:
 253         pm_runtime_put(&thdev->dev);
 254         module_put(thdrv->driver.owner);
 255
 256         return ret;
 257 }
 258
 259 static void intel_th_output_deactivate(struct intel_th_device *thdev)
 260 {
 261         struct intel_th_driver *thdrv =
 262                 to_intel_th_driver_or_null(thdev->dev.driver);
 263         struct intel_th *th = to_intel_th(thdev);
 264
 265         if (!thdrv)
 266                 return;
 267
 268         if (thdrv->deactivate)
 269                 thdrv->deactivate(thdev);
 270         else
 271                 intel_th_trace_disable(thdev);
 272
 273         if (th->deactivate)
 274                 th->deactivate(th);
 275
 276         pm_runtime_put(&thdev->dev);
 277         module_put(thdrv->driver.owner);
 278 }
 279
 280 static ssize_t active_show(struct device *dev, struct device_attribute *attr,
 281                            char *buf)
 282 {
 283         struct intel_th_device *thdev = to_intel_th_device(dev);
 284
 285         return scnprintf(buf, PAGE_SIZE, "%d\n", thdev->output.active);
 286 }
 287
 288 static ssize_t active_store(struct device *dev, struct device_attribute *attr,
 289                             const char *buf, size_t size)
 290 {
 291         struct intel_th_device *thdev = to_intel_th_device(dev);
 292         unsigned long val;
 293         int ret;
 294
 295         ret = kstrtoul(buf, 10, &val);
 296         if (ret)
 297                 return ret;
 298
 299         if (!!val != thdev->output.active) {
 300                 if (val)
 301                         ret = intel_th_output_activate(thdev);
 302                 else
 303                         intel_th_output_deactivate(thdev);
 304         }
 305
 306         return ret ? ret : size;
 307 }
 308
 309 static DEVICE_ATTR_RW(active);
 310
 311 static struct attribute *intel_th_output_attrs[] = {
 312         &dev_attr_port.attr,
 313         &dev_attr_active.attr,
 314         NULL,
 315 };
 316
 317 ATTRIBUTE_GROUPS(intel_th_output);
 318
 319 static struct device_type intel_th_output_device_type = {
 320         .name           = "intel_th_output_device",
 321         .groups         = intel_th_output_groups,
 322         .release        = intel_th_device_release,
 323         .devnode        = intel_th_output_devnode,
 324 };
 325
 326 static struct device_type intel_th_switch_device_type = {
 327         .name           = "intel_th_switch_device",
 328         .release        = intel_th_device_release,
 329 };
 330
 331 static struct device_type *intel_th_device_type[] = {
 332         [INTEL_TH_SOURCE]       = &intel_th_source_device_type,
 333         [INTEL_TH_OUTPUT]       = &intel_th_output_device_type,
 334         [INTEL_TH_SWITCH]       = &intel_th_switch_device_type,
 335 };
 336
 337 int intel_th_driver_register(struct intel_th_driver *thdrv)
 338 {
 339         if (!thdrv->probe || !thdrv->remove)
 340                 return -EINVAL;
 341
 342         thdrv->driver.bus = &intel_th_bus;
 343
 344         return driver_register(&thdrv->driver);
 345 }
 346 EXPORT_SYMBOL_GPL(intel_th_driver_register);
 347
 348 void intel_th_driver_unregister(struct intel_th_driver *thdrv)
 349 {
 350         driver_unregister(&thdrv->driver);
 351 }
 352 EXPORT_SYMBOL_GPL(intel_th_driver_unregister);
 353
 354 static struct intel_th_device *
 355 intel_th_device_alloc(struct intel_th *th, unsigned int type, const char *name,
 356                       int id)
 357 {
 358         struct device *parent;
 359         struct intel_th_device *thdev;
 360
 361         if (type == INTEL_TH_OUTPUT)
 362                 parent = &th->hub->dev;
 363         else
 364                 parent = th->dev;
 365
 366         thdev = kzalloc(sizeof(*thdev) + strlen(name) + 1, GFP_KERNEL);
 367         if (!thdev)
 368                 return NULL;
 369
 370         thdev->id = id;
 371         thdev->type = type;
 372
 373         strcpy(thdev->name, name);
 374         device_initialize(&thdev->dev);
 375         thdev->dev.bus = &intel_th_bus;
 376         thdev->dev.type = intel_th_device_type[type];
 377         thdev->dev.parent = parent;
 378         thdev->dev.dma_mask = parent->dma_mask;
 379         thdev->dev.dma_parms = parent->dma_parms;
 380         dma_set_coherent_mask(&thdev->dev, parent->coherent_dma_mask);
 381         if (id >= 0)
 382                 dev_set_name(&thdev->dev, "%d-%s%d", th->id, name, id);
 383         else
 384                 dev_set_name(&thdev->dev, "%d-%s", th->id, name);
 385
 386         return thdev;
 387 }
 388
 389 static int intel_th_device_add_resources(struct intel_th_device *thdev,
 390                                          struct resource *res, int nres)
 391 {
 392         struct resource *r;
 393
 394         r = kmemdup(res, sizeof(*res) * nres, GFP_KERNEL);
 395         if (!r)
 396                 return -ENOMEM;
 397
 398         thdev->resource = r;
 399         thdev->num_resources = nres;
 400
 401         return 0;
 402 }
 403
 404 static void intel_th_device_remove(struct intel_th_device *thdev)
 405 {
 406         device_del(&thdev->dev);
 407         put_device(&thdev->dev);
 408 }
 409
 410 static void intel_th_device_free(struct intel_th_device *thdev)
 411 {
 412         kfree(thdev->resource);
 413         kfree(thdev);
 414 }
 415
 416 /*
 417  * Intel(R) Trace Hub subdevices
 418  */
 419 static const struct intel_th_subdevice {
 420         const char              *name;
 421         struct resource         res[3];
 422         unsigned                nres;
 423         unsigned                type;
 424         unsigned                otype;
 425         unsigned                scrpd;
 426         int                     id;
 427 } intel_th_subdevices[] = {
 428         {
 429                 .nres   = 1,
 430                 .res    = {
 431                         {
 432                                 /* Handle TSCU from GTH driver */
 433                                 .start  = REG_GTH_OFFSET,
 434                                 .end    = REG_TSCU_OFFSET + REG_TSCU_LENGTH - 1,
 435                                 .flags  = IORESOURCE_MEM,
 436                         },
 437                 },
 438                 .name   = "gth",
 439                 .type   = INTEL_TH_SWITCH,
 440                 .id     = -1,
 441         },
 442         {
 443                 .nres   = 2,
 444                 .res    = {
 445                         {
 446                                 .start  = REG_MSU_OFFSET,
 447                                 .end    = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 448                                 .flags  = IORESOURCE_MEM,
 449                         },
 450                         {
 451                                 .start  = BUF_MSU_OFFSET,
 452                                 .end    = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 453                                 .flags  = IORESOURCE_MEM,
 454                         },
 455                 },
 456                 .name   = "msc",
 457                 .id     = 0,
 458                 .type   = INTEL_TH_OUTPUT,
 459                 .otype  = GTH_MSU,
 460                 .scrpd  = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC0_IS_ENABLED,
 461         },
 462         {
 463                 .nres   = 2,
 464                 .res    = {
 465                         {
 466                                 .start  = REG_MSU_OFFSET,
 467                                 .end    = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 468                                 .flags  = IORESOURCE_MEM,
 469                         },
 470                         {
 471                                 .start  = BUF_MSU_OFFSET,
 472                                 .end    = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 473                                 .flags  = IORESOURCE_MEM,
 474                         },
 475                 },
 476                 .name   = "msc",
 477                 .id     = 1,
 478                 .type   = INTEL_TH_OUTPUT,
 479                 .otype  = GTH_MSU,
 480                 .scrpd  = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC1_IS_ENABLED,
 481         },
 482         {
 483                 .nres   = 2,
 484                 .res    = {
 485                         {
 486                                 .start  = REG_STH_OFFSET,
 487                                 .end    = REG_STH_OFFSET + REG_STH_LENGTH - 1,
 488                                 .flags  = IORESOURCE_MEM,
 489                         },
 490                         {
 491                                 .start  = 1, /* use resource[1] */
 492                                 .end    = 0,
 493                                 .flags  = IORESOURCE_MEM,
 494                         },
 495                 },
 496                 .id     = -1,
 497                 .name   = "sth",
 498                 .type   = INTEL_TH_SOURCE,
 499         },
 500         {
 501                 .nres   = 1,
 502                 .res    = {
 503                         {
 504                                 .start  = REG_PTI_OFFSET,
 505                                 .end    = REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
 506                                 .flags  = IORESOURCE_MEM,
 507                         },
 508                 },
 509                 .id     = -1,
 510                 .name   = "pti",
 511                 .type   = INTEL_TH_OUTPUT,
 512                 .otype  = GTH_PTI,
 513                 .scrpd  = SCRPD_PTI_IS_PRIM_DEST,
 514         },
 515         {
 516                 .nres   = 1,
 517                 .res    = {
 518                         {
 519                                 .start  = REG_PTI_OFFSET,
 520                                 .end    = REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
 521                                 .flags  = IORESOURCE_MEM,
 522                         },
 523                 },
 524                 .id     = -1,
 525                 .name   = "lpp",
 526                 .type   = INTEL_TH_OUTPUT,
 527                 .otype  = GTH_LPP,
 528                 .scrpd  = SCRPD_PTI_IS_PRIM_DEST,
 529         },
 530         {
 531                 .nres   = 1,
 532                 .res    = {
 533                         {
 534                                 .start  = REG_DCIH_OFFSET,
 535                                 .end    = REG_DCIH_OFFSET + REG_DCIH_LENGTH - 1,
 536                                 .flags  = IORESOURCE_MEM,
 537                         },
 538                 },
 539                 .id     = -1,
 540                 .name   = "dcih",
 541                 .type   = INTEL_TH_OUTPUT,
 542         },
 543 };
 544
 545 #ifdef CONFIG_MODULES
 546 static void __intel_th_request_hub_module(struct work_struct *work)
 547 {
 548         struct intel_th *th = container_of(work, struct intel_th,
 549                                            request_module_work);
 550
 551         request_module("intel_th_%s", th->hub->name);
 552 }
 553
 554 static int intel_th_request_hub_module(struct intel_th *th)
 555 {
 556         INIT_WORK(&th->request_module_work, __intel_th_request_hub_module);
 557         schedule_work(&th->request_module_work);
 558
 559         return 0;
 560 }
 561
 562 static void intel_th_request_hub_module_flush(struct intel_th *th)
 563 {
 564         flush_work(&th->request_module_work);
 565 }
 566 #else
 567 static inline int intel_th_request_hub_module(struct intel_th *th)
 568 {
 569         return -EINVAL;
 570 }
 571
 572 static inline void intel_th_request_hub_module_flush(struct intel_th *th)
 573 {
 574 }
 575 #endif /* CONFIG_MODULES */
 576
 577 static struct intel_th_device *
 578 intel_th_subdevice_alloc(struct intel_th *th,
 579                          const struct intel_th_subdevice *subdev)
 580 {
 581         struct intel_th_device *thdev;
 582         struct resource res[3];
 583         unsigned int req = 0;
 584         bool is64bit = false;
 585         int r, err;
 586
 587         thdev = intel_th_device_alloc(th, subdev->type, subdev->name,
 588                                       subdev->id);
 589         if (!thdev)
 590                 return ERR_PTR(-ENOMEM);
 591
 592         thdev->drvdata = th->drvdata;
 593
 594         for (r = 0; r < th->num_resources; r++)
 595                 if (th->resource[r].flags & IORESOURCE_MEM_64) {
 596                         is64bit = true;
 597                         break;
 598                 }
 599
 600         memcpy(res, subdev->res,
 601                sizeof(struct resource) * subdev->nres);
 602
 603         for (r = 0; r < subdev->nres; r++) {
 604                 struct resource *devres = th->resource;
 605                 int bar = 0; /* cut subdevices' MMIO from resource[0] */
 606
 607                 /*
 608                  * Take .end == 0 to mean 'take the whole bar',
 609                  * .start then tells us which bar it is. Default to
 610                  * TH_MMIO_CONFIG.
 611                  */
 612                 if (!res[r].end && res[r].flags == IORESOURCE_MEM) {
 613                         bar = res[r].start;
 614                         if (is64bit)
 615                                 bar *= 2;
 616                         res[r].start = 0;
 617                         res[r].end = resource_size(&devres[bar]) - 1;
 618                 }
 619
 620                 if (res[r].flags & IORESOURCE_MEM) {
 621                         res[r].start    += devres[bar].start;
 622                         res[r].end      += devres[bar].start;
 623
 624                         dev_dbg(th->dev, "%s:%d @ %pR\n",
 625                                 subdev->name, r, &res[r]);
 626                 } else if (res[r].flags & IORESOURCE_IRQ) {
 627                         res[r].start    = th->irq;
 628                 }
 629         }
 630
 631         err = intel_th_device_add_resources(thdev, res, subdev->nres);
 632         if (err) {
 633                 put_device(&thdev->dev);
 634                 goto fail_put_device;
 635         }
 636
 637         if (subdev->type == INTEL_TH_OUTPUT) {
 638                 thdev->dev.devt = MKDEV(th->major, th->num_thdevs);
 639                 thdev->output.type = subdev->otype;
 640                 thdev->output.port = -1;
 641                 thdev->output.scratchpad = subdev->scrpd;
 642         } else if (subdev->type == INTEL_TH_SWITCH) {
 643                 thdev->host_mode =
 644                         INTEL_TH_CAP(th, host_mode_only) ? true : host_mode;
 645                 th->hub = thdev;
 646         }
 647
 648         err = device_add(&thdev->dev);
 649         if (err) {
 650                 put_device(&thdev->dev);
 651                 goto fail_free_res;
 652         }
 653
 654         /* need switch driver to be loaded to enumerate the rest */
 655         if (subdev->type == INTEL_TH_SWITCH && !req) {
 656                 err = intel_th_request_hub_module(th);
 657                 if (!err)
 658                         req++;
 659         }
 660
 661         return thdev;
 662
 663 fail_free_res:
 664         kfree(thdev->resource);
 665
 666 fail_put_device:
 667         put_device(&thdev->dev);
 668
 669         return ERR_PTR(err);
 670 }
 671
 672 /**
 673  * intel_th_output_enable() - find and enable a device for a given output type
 674  * @th:         Intel TH instance
 675  * @otype:      output type
 676  *
 677  * Go through the unallocated output devices, find the first one whos type
 678  * matches @otype and instantiate it. These devices are removed when the hub
 679  * device is removed, see intel_th_remove().
 680  */
 681 int intel_th_output_enable(struct intel_th *th, unsigned int otype)
 682 {
 683         struct intel_th_device *thdev;
 684         int src = 0, dst = 0;
 685
 686         for (src = 0, dst = 0; dst <= th->num_thdevs; src++, dst++) {
 687                 for (; src < ARRAY_SIZE(intel_th_subdevices); src++) {
 688                         if (intel_th_subdevices[src].type != INTEL_TH_OUTPUT)
 689                                 continue;
 690
 691                         if (intel_th_subdevices[src].otype != otype)
 692                                 continue;
 693
 694                         break;
 695                 }
 696
 697                 /* no unallocated matching subdevices */
 698                 if (src == ARRAY_SIZE(intel_th_subdevices))
 699                         return -ENODEV;
 700
 701                 for (; dst < th->num_thdevs; dst++) {
 702                         if (th->thdev[dst]->type != INTEL_TH_OUTPUT)
 703                                 continue;
 704
 705                         if (th->thdev[dst]->output.type != otype)
 706                                 continue;
 707
 708                         break;
 709                 }
 710
 711                 /*
 712                  * intel_th_subdevices[src] matches our requirements and is
 713                  * not matched in th::thdev[]
 714                  */
 715                 if (dst == th->num_thdevs)
 716                         goto found;
 717         }
 718
 719         return -ENODEV;
 720
 721 found:
 722         thdev = intel_th_subdevice_alloc(th, &intel_th_subdevices[src]);
 723         if (IS_ERR(thdev))
 724                 return PTR_ERR(thdev);
 725
 726         th->thdev[th->num_thdevs++] = thdev;
 727
 728         return 0;
 729 }
 730 EXPORT_SYMBOL_GPL(intel_th_output_enable);
 731
 732 static int intel_th_populate(struct intel_th *th)
 733 {
 734         int src;
 735
 736         /* create devices for each intel_th_subdevice */
 737         for (src = 0; src < ARRAY_SIZE(intel_th_subdevices); src++) {
 738                 const struct intel_th_subdevice *subdev =
 739                         &intel_th_subdevices[src];
 740                 struct intel_th_device *thdev;
 741
 742                 /* only allow SOURCE and SWITCH devices in host mode */
 743                 if ((INTEL_TH_CAP(th, host_mode_only) || host_mode) &&
 744                     subdev->type == INTEL_TH_OUTPUT)
 745                         continue;
 746
 747                 /*
 748                  * don't enable port OUTPUTs in this path; SWITCH enables them
 749                  * via intel_th_output_enable()
 750                  */
 751                 if (subdev->type == INTEL_TH_OUTPUT &&
 752                     subdev->otype != GTH_NONE)
 753                         continue;
 754
 755                 thdev = intel_th_subdevice_alloc(th, subdev);
 756                 /* note: caller should free subdevices from th::thdev[] */
 757                 if (IS_ERR(thdev))
 758                         return PTR_ERR(thdev);
 759
 760                 th->thdev[th->num_thdevs++] = thdev;
 761         }
 762
 763         return 0;
 764 }
 765
 766 static int match_devt(struct device *dev, void *data)
 767 {
 768         dev_t devt = (dev_t)(unsigned long)data;
 769
 770         return dev->devt == devt;
 771 }
 772
 773 static int intel_th_output_open(struct inode *inode, struct file *file)
 774 {
 775         const struct file_operations *fops;
 776         struct intel_th_driver *thdrv;
 777         struct device *dev;
 778         int err;
 779
 780         dev = bus_find_device(&intel_th_bus, NULL,
 781                               (void *)(unsigned long)inode->i_rdev,
 782                               match_devt);
 783         if (!dev || !dev->driver)
 784                 return -ENODEV;
 785
 786         thdrv = to_intel_th_driver(dev->driver);
 787         fops = fops_get(thdrv->fops);
 788         if (!fops)
 789                 return -ENODEV;
 790
 791         replace_fops(file, fops);
 792
 793         file->private_data = to_intel_th_device(dev);
 794
 795         if (file->f_op->open) {
 796                 err = file->f_op->open(inode, file);
 797                 return err;
 798         }
 799
 800         return 0;
 801 }
 802
 803 static const struct file_operations intel_th_output_fops = {
 804         .open   = intel_th_output_open,
 805         .llseek = noop_llseek,
 806 };
 807
 808 /**
 809  * intel_th_alloc() - allocate a new Intel TH device and its subdevices
 810  * @dev:        parent device
 811  * @devres:     parent's resources
 812  * @ndevres:    number of resources
 813  * @irq:        irq number
 814  */
 815 struct intel_th *
 816 intel_th_alloc(struct device *dev, struct intel_th_drvdata *drvdata,
 817                struct resource *devres, unsigned int ndevres, int irq)
 818 {
 819         struct intel_th *th;
 820         int err, r;
 821
 822         if (irq == -1)
 823                 for (r = 0; r < ndevres; r++)
 824                         if (devres[r].flags & IORESOURCE_IRQ) {
 825                                 irq = devres[r].start;
 826                                 break;
 827                         }
 828
 829         th = kzalloc(sizeof(*th), GFP_KERNEL);
 830         if (!th)
 831                 return ERR_PTR(-ENOMEM);
 832
 833         th->id = ida_simple_get(&intel_th_ida, 0, 0, GFP_KERNEL);
 834         if (th->id < 0) {
 835                 err = th->id;
 836                 goto err_alloc;
 837         }
 838
 839         th->major = __register_chrdev(0, 0, TH_POSSIBLE_OUTPUTS,
 840                                       "intel_th/output", &intel_th_output_fops);
 841         if (th->major < 0) {
 842                 err = th->major;
 843                 goto err_ida;
 844         }
 845         th->dev = dev;
 846         th->drvdata = drvdata;
 847
 848         th->resource = devres;
 849         th->num_resources = ndevres;
 850         th->irq = irq;
 851
 852         dev_set_drvdata(dev, th);
 853
 854         pm_runtime_no_callbacks(dev);
 855         pm_runtime_put(dev);
 856         pm_runtime_allow(dev);
 857
 858         err = intel_th_populate(th);
 859         if (err) {
 860                 /* free the subdevices and undo everything */
 861                 intel_th_free(th);
 862                 return ERR_PTR(err);
 863         }
 864
 865         return th;
 866
 867 err_ida:
 868         ida_simple_remove(&intel_th_ida, th->id);
 869
 870 err_alloc:
 871         kfree(th);
 872
 873         return ERR_PTR(err);
 874 }
 875 EXPORT_SYMBOL_GPL(intel_th_alloc);
 876
 877 void intel_th_free(struct intel_th *th)
 878 {
 879         int i;
 880
 881         intel_th_request_hub_module_flush(th);
 882
 883         intel_th_device_remove(th->hub);
 884         for (i = 0; i < th->num_thdevs; i++) {
 885                 if (th->thdev[i] != th->hub)
 886                         intel_th_device_remove(th->thdev[i]);
 887                 th->thdev[i] = NULL;
 888         }
 889
 890         th->num_thdevs = 0;
 891
 892         pm_runtime_get_sync(th->dev);
 893         pm_runtime_forbid(th->dev);
 894
 895         __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
 896                             "intel_th/output");
 897
 898         ida_simple_remove(&intel_th_ida, th->id);
 899
 900         kfree(th);
 901 }
 902 EXPORT_SYMBOL_GPL(intel_th_free);
 903
 904 /**
 905  * intel_th_trace_enable() - enable tracing for an output device
 906  * @thdev:      output device that requests tracing be enabled
 907  */
 908 int intel_th_trace_enable(struct intel_th_device *thdev)
 909 {
 910         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 911         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 912
 913         if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
 914                 return -EINVAL;
 915
 916         if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
 917                 return -EINVAL;
 918
 919         pm_runtime_get_sync(&thdev->dev);
 920         hubdrv->enable(hub, &thdev->output);
 921
 922         return 0;
 923 }
 924 EXPORT_SYMBOL_GPL(intel_th_trace_enable);
 925
 926 /**
 927  * intel_th_trace_disable() - disable tracing for an output device
 928  * @thdev:      output device that requests tracing be disabled
 929  */
 930 int intel_th_trace_disable(struct intel_th_device *thdev)
 931 {
 932         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 933         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 934
 935         WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH);
 936         if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
 937                 return -EINVAL;
 938
 939         hubdrv->disable(hub, &thdev->output);
 940         pm_runtime_put(&thdev->dev);
 941
 942         return 0;
 943 }
 944 EXPORT_SYMBOL_GPL(intel_th_trace_disable);
 945
 946 int intel_th_set_output(struct intel_th_device *thdev,
 947                         unsigned int master)
 948 {
 949         struct intel_th_device *hub = to_intel_th_hub(thdev);
 950         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 951
 952         /* In host mode, this is up to the external debugger, do nothing. */
 953         if (hub->host_mode)
 954                 return 0;
 955
 956         if (!hubdrv->set_output)
 957                 return -ENOTSUPP;
 958
 959         return hubdrv->set_output(hub, master);
 960 }
 961 EXPORT_SYMBOL_GPL(intel_th_set_output);
 962
 963 static int __init intel_th_init(void)
 964 {
 965         intel_th_debug_init();
 966
 967         return bus_register(&intel_th_bus);
 968 }
 969 subsys_initcall(intel_th_init);
 970
 971 static void __exit intel_th_exit(void)
 972 {
 973         intel_th_debug_done();
 974
 975         bus_unregister(&intel_th_bus);
 976 }
 977 module_exit(intel_th_exit);
 978
 979 MODULE_LICENSE("GPL v2");
 980 MODULE_DESCRIPTION("Intel(R) Trace Hub controller driver");
 981 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");