kernel/drivers/hwtracing/intel_th/core.c

   1 /*
   2  * Intel(R) Trace Hub driver core
   3  *
   4  * Copyright (C) 2014-2015 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  */
  15
  16 #define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
  17
  18 #include <linux/types.h>
  19 #include <linux/module.h>
  20 #include <linux/device.h>
  21 #include <linux/sysfs.h>
  22 #include <linux/kdev_t.h>
  23 #include <linux/debugfs.h>
  24 #include <linux/idr.h>
  25 #include <linux/pci.h>
  26 #include <linux/dma-mapping.h>
  27
  28 #include "intel_th.h"
  29 #include "debug.h"
  30
  31 static DEFINE_IDA(intel_th_ida);
  32
  33 static int intel_th_match(struct device *dev, struct device_driver *driver)
  34 {
  35         struct intel_th_driver *thdrv = to_intel_th_driver(driver);
  36         struct intel_th_device *thdev = to_intel_th_device(dev);
  37
  38         if (thdev->type == INTEL_TH_SWITCH &&
  39             (!thdrv->enable || !thdrv->disable))
  40                 return 0;
  41
  42         return !strcmp(thdev->name, driver->name);
  43 }
  44
  45 static int intel_th_child_remove(struct device *dev, void *data)
  46 {
  47         device_release_driver(dev);
  48
  49         return 0;
  50 }
  51
  52 static int intel_th_probe(struct device *dev)
  53 {
  54         struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
  55         struct intel_th_device *thdev = to_intel_th_device(dev);
  56         struct intel_th_driver *hubdrv;
  57         struct intel_th_device *hub = NULL;
  58         int ret;
  59
  60         if (thdev->type == INTEL_TH_SWITCH)
  61                 hub = thdev;
  62         else if (dev->parent)
  63                 hub = to_intel_th_device(dev->parent);
  64
  65         if (!hub || !hub->dev.driver)
  66                 return -EPROBE_DEFER;
  67
  68         hubdrv = to_intel_th_driver(hub->dev.driver);
  69
  70         ret = thdrv->probe(to_intel_th_device(dev));
  71         if (ret)
  72                 return ret;
  73
  74         if (thdev->type == INTEL_TH_OUTPUT &&
  75             !intel_th_output_assigned(thdev))
  76                 ret = hubdrv->assign(hub, thdev);
  77
  78         return ret;
  79 }
  80
  81 static int intel_th_remove(struct device *dev)
  82 {
  83         struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
  84         struct intel_th_device *thdev = to_intel_th_device(dev);
  85         struct intel_th_device *hub = to_intel_th_device(dev->parent);
  86         int err;
  87
  88         if (thdev->type == INTEL_TH_SWITCH) {
  89                 err = device_for_each_child(dev, thdev, intel_th_child_remove);
  90                 if (err)
  91                         return err;
  92         }
  93
  94         thdrv->remove(thdev);
  95
  96         if (intel_th_output_assigned(thdev)) {
  97                 struct intel_th_driver *hubdrv =
  98                         to_intel_th_driver(dev->parent->driver);
  99
 100                 if (hub->dev.driver)
 101                         hubdrv->unassign(hub, thdev);
 102         }
 103
 104         return 0;
 105 }
 106
 107 static struct bus_type intel_th_bus = {
 108         .name           = "intel_th",
 109         .dev_attrs      = NULL,
 110         .match          = intel_th_match,
 111         .probe          = intel_th_probe,
 112         .remove         = intel_th_remove,
 113 };
 114
 115 static void intel_th_device_free(struct intel_th_device *thdev);
 116
 117 static void intel_th_device_release(struct device *dev)
 118 {
 119         intel_th_device_free(to_intel_th_device(dev));
 120 }
 121
 122 static struct device_type intel_th_source_device_type = {
 123         .name           = "intel_th_source_device",
 124         .release        = intel_th_device_release,
 125 };
 126
 127 static char *intel_th_output_devnode(struct device *dev, umode_t *mode,
 128                                      kuid_t *uid, kgid_t *gid)
 129 {
 130         struct intel_th_device *thdev = to_intel_th_device(dev);
 131         char *node;
 132
 133         if (thdev->id >= 0)
 134                 node = kasprintf(GFP_KERNEL, "intel_th%d/%s%d", 0, thdev->name,
 135                                  thdev->id);
 136         else
 137                 node = kasprintf(GFP_KERNEL, "intel_th%d/%s", 0, thdev->name);
 138
 139         return node;
 140 }
 141
 142 static ssize_t port_show(struct device *dev, struct device_attribute *attr,
 143                          char *buf)
 144 {
 145         struct intel_th_device *thdev = to_intel_th_device(dev);
 146
 147         if (thdev->output.port >= 0)
 148                 return scnprintf(buf, PAGE_SIZE, "%u\n", thdev->output.port);
 149
 150         return scnprintf(buf, PAGE_SIZE, "unassigned\n");
 151 }
 152
 153 static DEVICE_ATTR_RO(port);
 154
 155 static int intel_th_output_activate(struct intel_th_device *thdev)
 156 {
 157         struct intel_th_driver *thdrv = to_intel_th_driver(thdev->dev.driver);
 158
 159         if (thdrv->activate)
 160                 return thdrv->activate(thdev);
 161
 162         intel_th_trace_enable(thdev);
 163
 164         return 0;
 165 }
 166
 167 static void intel_th_output_deactivate(struct intel_th_device *thdev)
 168 {
 169         struct intel_th_driver *thdrv = to_intel_th_driver(thdev->dev.driver);
 170
 171         if (thdrv->deactivate)
 172                 thdrv->deactivate(thdev);
 173         else
 174                 intel_th_trace_disable(thdev);
 175 }
 176
 177 static ssize_t active_show(struct device *dev, struct device_attribute *attr,
 178                            char *buf)
 179 {
 180         struct intel_th_device *thdev = to_intel_th_device(dev);
 181
 182         return scnprintf(buf, PAGE_SIZE, "%d\n", thdev->output.active);
 183 }
 184
 185 static ssize_t active_store(struct device *dev, struct device_attribute *attr,
 186                             const char *buf, size_t size)
 187 {
 188         struct intel_th_device *thdev = to_intel_th_device(dev);
 189         unsigned long val;
 190         int ret;
 191
 192         ret = kstrtoul(buf, 10, &val);
 193         if (ret)
 194                 return ret;
 195
 196         if (!!val != thdev->output.active) {
 197                 if (val)
 198                         ret = intel_th_output_activate(thdev);
 199                 else
 200                         intel_th_output_deactivate(thdev);
 201         }
 202
 203         return ret ? ret : size;
 204 }
 205
 206 static DEVICE_ATTR_RW(active);
 207
 208 static struct attribute *intel_th_output_attrs[] = {
 209         &dev_attr_port.attr,
 210         &dev_attr_active.attr,
 211         NULL,
 212 };
 213
 214 ATTRIBUTE_GROUPS(intel_th_output);
 215
 216 static struct device_type intel_th_output_device_type = {
 217         .name           = "intel_th_output_device",
 218         .groups         = intel_th_output_groups,
 219         .release        = intel_th_device_release,
 220         .devnode        = intel_th_output_devnode,
 221 };
 222
 223 static struct device_type intel_th_switch_device_type = {
 224         .name           = "intel_th_switch_device",
 225         .release        = intel_th_device_release,
 226 };
 227
 228 static struct device_type *intel_th_device_type[] = {
 229         [INTEL_TH_SOURCE]       = &intel_th_source_device_type,
 230         [INTEL_TH_OUTPUT]       = &intel_th_output_device_type,
 231         [INTEL_TH_SWITCH]       = &intel_th_switch_device_type,
 232 };
 233
 234 int intel_th_driver_register(struct intel_th_driver *thdrv)
 235 {
 236         if (!thdrv->probe || !thdrv->remove)
 237                 return -EINVAL;
 238
 239         thdrv->driver.bus = &intel_th_bus;
 240
 241         return driver_register(&thdrv->driver);
 242 }
 243 EXPORT_SYMBOL_GPL(intel_th_driver_register);
 244
 245 void intel_th_driver_unregister(struct intel_th_driver *thdrv)
 246 {
 247         driver_unregister(&thdrv->driver);
 248 }
 249 EXPORT_SYMBOL_GPL(intel_th_driver_unregister);
 250
 251 static struct intel_th_device *
 252 intel_th_device_alloc(struct intel_th *th, unsigned int type, const char *name,
 253                       int id)
 254 {
 255         struct device *parent;
 256         struct intel_th_device *thdev;
 257
 258         if (type == INTEL_TH_SWITCH)
 259                 parent = th->dev;
 260         else
 261                 parent = &th->hub->dev;
 262
 263         thdev = kzalloc(sizeof(*thdev) + strlen(name) + 1, GFP_KERNEL);
 264         if (!thdev)
 265                 return NULL;
 266
 267         thdev->id = id;
 268         thdev->type = type;
 269
 270         strcpy(thdev->name, name);
 271         device_initialize(&thdev->dev);
 272         thdev->dev.bus = &intel_th_bus;
 273         thdev->dev.type = intel_th_device_type[type];
 274         thdev->dev.parent = parent;
 275         thdev->dev.dma_mask = parent->dma_mask;
 276         thdev->dev.dma_parms = parent->dma_parms;
 277         dma_set_coherent_mask(&thdev->dev, parent->coherent_dma_mask);
 278         if (id >= 0)
 279                 dev_set_name(&thdev->dev, "%d-%s%d", th->id, name, id);
 280         else
 281                 dev_set_name(&thdev->dev, "%d-%s", th->id, name);
 282
 283         return thdev;
 284 }
 285
 286 static int intel_th_device_add_resources(struct intel_th_device *thdev,
 287                                          struct resource *res, int nres)
 288 {
 289         struct resource *r;
 290
 291         r = kmemdup(res, sizeof(*res) * nres, GFP_KERNEL);
 292         if (!r)
 293                 return -ENOMEM;
 294
 295         thdev->resource = r;
 296         thdev->num_resources = nres;
 297
 298         return 0;
 299 }
 300
 301 static void intel_th_device_remove(struct intel_th_device *thdev)
 302 {
 303         device_del(&thdev->dev);
 304         put_device(&thdev->dev);
 305 }
 306
 307 static void intel_th_device_free(struct intel_th_device *thdev)
 308 {
 309         kfree(thdev->resource);
 310         kfree(thdev);
 311 }
 312
 313 /*
 314  * Intel(R) Trace Hub subdevices
 315  */
 316 static struct intel_th_subdevice {
 317         const char              *name;
 318         struct resource         res[3];
 319         unsigned                nres;
 320         unsigned                type;
 321         unsigned                otype;
 322         int                     id;
 323 } intel_th_subdevices[TH_SUBDEVICE_MAX] = {
 324         {
 325                 .nres   = 1,
 326                 .res    = {
 327                         {
 328                                 .start  = REG_GTH_OFFSET,
 329                                 .end    = REG_GTH_OFFSET + REG_GTH_LENGTH - 1,
 330                                 .flags  = IORESOURCE_MEM,
 331                         },
 332                 },
 333                 .name   = "gth",
 334                 .type   = INTEL_TH_SWITCH,
 335                 .id     = -1,
 336         },
 337         {
 338                 .nres   = 2,
 339                 .res    = {
 340                         {
 341                                 .start  = REG_MSU_OFFSET,
 342                                 .end    = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 343                                 .flags  = IORESOURCE_MEM,
 344                         },
 345                         {
 346                                 .start  = BUF_MSU_OFFSET,
 347                                 .end    = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 348                                 .flags  = IORESOURCE_MEM,
 349                         },
 350                 },
 351                 .name   = "msc",
 352                 .id     = 0,
 353                 .type   = INTEL_TH_OUTPUT,
 354                 .otype  = GTH_MSU,
 355         },
 356         {
 357                 .nres   = 2,
 358                 .res    = {
 359                         {
 360                                 .start  = REG_MSU_OFFSET,
 361                                 .end    = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
 362                                 .flags  = IORESOURCE_MEM,
 363                         },
 364                         {
 365                                 .start  = BUF_MSU_OFFSET,
 366                                 .end    = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
 367                                 .flags  = IORESOURCE_MEM,
 368                         },
 369                 },
 370                 .name   = "msc",
 371                 .id     = 1,
 372                 .type   = INTEL_TH_OUTPUT,
 373                 .otype  = GTH_MSU,
 374         },
 375         {
 376                 .nres   = 2,
 377                 .res    = {
 378                         {
 379                                 .start  = REG_STH_OFFSET,
 380                                 .end    = REG_STH_OFFSET + REG_STH_LENGTH - 1,
 381                                 .flags  = IORESOURCE_MEM,
 382                         },
 383                         {
 384                                 .start  = TH_MMIO_SW,
 385                                 .end    = 0,
 386                                 .flags  = IORESOURCE_MEM,
 387                         },
 388                 },
 389                 .id     = -1,
 390                 .name   = "sth",
 391                 .type   = INTEL_TH_SOURCE,
 392         },
 393         {
 394                 .nres   = 1,
 395                 .res    = {
 396                         {
 397                                 .start  = REG_PTI_OFFSET,
 398                                 .end    = REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
 399                                 .flags  = IORESOURCE_MEM,
 400                         },
 401                 },
 402                 .id     = -1,
 403                 .name   = "pti",
 404                 .type   = INTEL_TH_OUTPUT,
 405                 .otype  = GTH_PTI,
 406         },
 407         {
 408                 .nres   = 1,
 409                 .res    = {
 410                         {
 411                                 .start  = REG_DCIH_OFFSET,
 412                                 .end    = REG_DCIH_OFFSET + REG_DCIH_LENGTH - 1,
 413                                 .flags  = IORESOURCE_MEM,
 414                         },
 415                 },
 416                 .id     = -1,
 417                 .name   = "dcih",
 418                 .type   = INTEL_TH_OUTPUT,
 419         },
 420 };
 421
 422 static int intel_th_populate(struct intel_th *th, struct resource *devres,
 423                              unsigned int ndevres, int irq)
 424 {
 425         struct resource res[3];
 426         unsigned int req = 0;
 427         int i, err;
 428
 429         /* create devices for each intel_th_subdevice */
 430         for (i = 0; i < ARRAY_SIZE(intel_th_subdevices); i++) {
 431                 struct intel_th_subdevice *subdev = &intel_th_subdevices[i];
 432                 struct intel_th_device *thdev;
 433                 int r;
 434
 435                 thdev = intel_th_device_alloc(th, subdev->type, subdev->name,
 436                                               subdev->id);
 437                 if (!thdev) {
 438                         err = -ENOMEM;
 439                         goto kill_subdevs;
 440                 }
 441
 442                 memcpy(res, subdev->res,
 443                        sizeof(struct resource) * subdev->nres);
 444
 445                 for (r = 0; r < subdev->nres; r++) {
 446                         int bar = TH_MMIO_CONFIG;
 447
 448                         /*
 449                          * Take .end == 0 to mean 'take the whole bar',
 450                          * .start then tells us which bar it is. Default to
 451                          * TH_MMIO_CONFIG.
 452                          */
 453                         if (!res[r].end && res[r].flags == IORESOURCE_MEM) {
 454                                 bar = res[r].start;
 455                                 res[r].start = 0;
 456                                 res[r].end = resource_size(&devres[bar]) - 1;
 457                         }
 458
 459                         if (res[r].flags & IORESOURCE_MEM) {
 460                                 res[r].start    += devres[bar].start;
 461                                 res[r].end      += devres[bar].start;
 462
 463                                 dev_dbg(th->dev, "%s:%d @ %pR\n",
 464                                         subdev->name, r, &res[r]);
 465                         } else if (res[r].flags & IORESOURCE_IRQ) {
 466                                 res[r].start    = irq;
 467                         }
 468                 }
 469
 470                 err = intel_th_device_add_resources(thdev, res, subdev->nres);
 471                 if (err) {
 472                         put_device(&thdev->dev);
 473                         goto kill_subdevs;
 474                 }
 475
 476                 if (subdev->type == INTEL_TH_OUTPUT) {
 477                         thdev->dev.devt = MKDEV(th->major, i);
 478                         thdev->output.type = subdev->otype;
 479                         thdev->output.port = -1;
 480                 }
 481
 482                 err = device_add(&thdev->dev);
 483                 if (err) {
 484                         put_device(&thdev->dev);
 485                         goto kill_subdevs;
 486                 }
 487
 488                 /* need switch driver to be loaded to enumerate the rest */
 489                 if (subdev->type == INTEL_TH_SWITCH && !req) {
 490                         th->hub = thdev;
 491                         err = request_module("intel_th_%s", subdev->name);
 492                         if (!err)
 493                                 req++;
 494                 }
 495
 496                 th->thdev[i] = thdev;
 497         }
 498
 499         return 0;
 500
 501 kill_subdevs:
 502         for (i-- ; i >= 0; i--)
 503                 intel_th_device_remove(th->thdev[i]);
 504
 505         return err;
 506 }
 507
 508 static int match_devt(struct device *dev, void *data)
 509 {
 510         dev_t devt = (dev_t)(unsigned long)data;
 511
 512         return dev->devt == devt;
 513 }
 514
 515 static int intel_th_output_open(struct inode *inode, struct file *file)
 516 {
 517         const struct file_operations *fops;
 518         struct intel_th_driver *thdrv;
 519         struct device *dev;
 520         int err;
 521
 522         dev = bus_find_device(&intel_th_bus, NULL,
 523                               (void *)(unsigned long)inode->i_rdev,
 524                               match_devt);
 525         if (!dev || !dev->driver)
 526                 return -ENODEV;
 527
 528         thdrv = to_intel_th_driver(dev->driver);
 529         fops = fops_get(thdrv->fops);
 530         if (!fops)
 531                 return -ENODEV;
 532
 533         replace_fops(file, fops);
 534
 535         file->private_data = to_intel_th_device(dev);
 536
 537         if (file->f_op->open) {
 538                 err = file->f_op->open(inode, file);
 539                 return err;
 540         }
 541
 542         return 0;
 543 }
 544
 545 static const struct file_operations intel_th_output_fops = {
 546         .open   = intel_th_output_open,
 547         .llseek = noop_llseek,
 548 };
 549
 550 /**
 551  * intel_th_alloc() - allocate a new Intel TH device and its subdevices
 552  * @dev:        parent device
 553  * @devres:     parent's resources
 554  * @ndevres:    number of resources
 555  * @irq:        irq number
 556  */
 557 struct intel_th *
 558 intel_th_alloc(struct device *dev, struct resource *devres,
 559                unsigned int ndevres, int irq)
 560 {
 561         struct intel_th *th;
 562         int err;
 563
 564         th = kzalloc(sizeof(*th), GFP_KERNEL);
 565         if (!th)
 566                 return ERR_PTR(-ENOMEM);
 567
 568         th->id = ida_simple_get(&intel_th_ida, 0, 0, GFP_KERNEL);
 569         if (th->id < 0) {
 570                 err = th->id;
 571                 goto err_alloc;
 572         }
 573
 574         th->major = __register_chrdev(0, 0, TH_POSSIBLE_OUTPUTS,
 575                                       "intel_th/output", &intel_th_output_fops);
 576         if (th->major < 0) {
 577                 err = th->major;
 578                 goto err_ida;
 579         }
 580         th->dev = dev;
 581
 582         err = intel_th_populate(th, devres, ndevres, irq);
 583         if (err)
 584                 goto err_chrdev;
 585
 586         return th;
 587
 588 err_chrdev:
 589         __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
 590                             "intel_th/output");
 591
 592 err_ida:
 593         ida_simple_remove(&intel_th_ida, th->id);
 594
 595 err_alloc:
 596         kfree(th);
 597
 598         return ERR_PTR(err);
 599 }
 600 EXPORT_SYMBOL_GPL(intel_th_alloc);
 601
 602 void intel_th_free(struct intel_th *th)
 603 {
 604         int i;
 605
 606         for (i = 0; i < TH_SUBDEVICE_MAX; i++)
 607                 if (th->thdev[i] != th->hub)
 608                         intel_th_device_remove(th->thdev[i]);
 609
 610         intel_th_device_remove(th->hub);
 611
 612         __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
 613                             "intel_th/output");
 614
 615         ida_simple_remove(&intel_th_ida, th->id);
 616
 617         kfree(th);
 618 }
 619 EXPORT_SYMBOL_GPL(intel_th_free);
 620
 621 /**
 622  * intel_th_trace_enable() - enable tracing for an output device
 623  * @thdev:      output device that requests tracing be enabled
 624  */
 625 int intel_th_trace_enable(struct intel_th_device *thdev)
 626 {
 627         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 628         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 629
 630         if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
 631                 return -EINVAL;
 632
 633         if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
 634                 return -EINVAL;
 635
 636         hubdrv->enable(hub, &thdev->output);
 637
 638         return 0;
 639 }
 640 EXPORT_SYMBOL_GPL(intel_th_trace_enable);
 641
 642 /**
 643  * intel_th_trace_disable() - disable tracing for an output device
 644  * @thdev:      output device that requests tracing be disabled
 645  */
 646 int intel_th_trace_disable(struct intel_th_device *thdev)
 647 {
 648         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 649         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 650
 651         WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH);
 652         if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
 653                 return -EINVAL;
 654
 655         hubdrv->disable(hub, &thdev->output);
 656
 657         return 0;
 658 }
 659 EXPORT_SYMBOL_GPL(intel_th_trace_disable);
 660
 661 int intel_th_set_output(struct intel_th_device *thdev,
 662                         unsigned int master)
 663 {
 664         struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
 665         struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
 666
 667         if (!hubdrv->set_output)
 668                 return -ENOTSUPP;
 669
 670         return hubdrv->set_output(hub, master);
 671 }
 672 EXPORT_SYMBOL_GPL(intel_th_set_output);
 673
 674 static int __init intel_th_init(void)
 675 {
 676         intel_th_debug_init();
 677
 678         return bus_register(&intel_th_bus);
 679 }
 680 subsys_initcall(intel_th_init);
 681
 682 static void __exit intel_th_exit(void)
 683 {
 684         intel_th_debug_done();
 685
 686         bus_unregister(&intel_th_bus);
 687 }
 688 module_exit(intel_th_exit);
 689
 690 MODULE_LICENSE("GPL v2");
 691 MODULE_DESCRIPTION("Intel(R) Trace Hub controller driver");
 692 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");