root/drivers/bus/fsl-mc/dprc-driver.c

DEFINITIONS

1. fsl_mc_device_match
2. __fsl_mc_device_remove_if_not_in_mc
3. __fsl_mc_device_remove
4. dprc_remove_devices
5. __fsl_mc_device_match
6. fsl_mc_device_lookup
7. check_plugged_state_change
8. dprc_add_new_devices
9. dprc_scan_objects
10. dprc_scan_container
11. dprc_irq0_handler
12. dprc_irq0_handler_thread
13. disable_dprc_irq
14. register_dprc_irq_handler
15. enable_dprc_irq
16. dprc_setup_irq
17. dprc_probe
18. dprc_teardown_irq
19. dprc_remove
20. dprc_driver_init
21. dprc_driver_exit

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Freescale data path resource container (DPRC) driver
   4  *
   5  * Copyright (C) 2014-2016 Freescale Semiconductor, Inc.
   6  * Author: German Rivera <German.Rivera@freescale.com>
   7  *
   8  */
   9 
  10 #include <linux/module.h>
  11 #include <linux/slab.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/msi.h>
  14 #include <linux/fsl/mc.h>
  15 
  16 #include "fsl-mc-private.h"
  17 
  18 #define FSL_MC_DPRC_DRIVER_NAME    "fsl_mc_dprc"
  19 
  20 struct fsl_mc_child_objs {
  21         int child_count;
  22         struct fsl_mc_obj_desc *child_array;
  23 };
  24 
  25 static bool fsl_mc_device_match(struct fsl_mc_device *mc_dev,
  26                                 struct fsl_mc_obj_desc *obj_desc)
  27 {
  28         return mc_dev->obj_desc.id == obj_desc->id &&
  29                strcmp(mc_dev->obj_desc.type, obj_desc->type) == 0;
  30 
  31 }
  32 
  33 static int __fsl_mc_device_remove_if_not_in_mc(struct device *dev, void *data)
  34 {
  35         int i;
  36         struct fsl_mc_child_objs *objs;
  37         struct fsl_mc_device *mc_dev;
  38 
  39         mc_dev = to_fsl_mc_device(dev);
  40         objs = data;
  41 
  42         for (i = 0; i < objs->child_count; i++) {
  43                 struct fsl_mc_obj_desc *obj_desc = &objs->child_array[i];
  44 
  45                 if (strlen(obj_desc->type) != 0 &&
  46                     fsl_mc_device_match(mc_dev, obj_desc))
  47                         break;
  48         }
  49 
  50         if (i == objs->child_count)
  51                 fsl_mc_device_remove(mc_dev);
  52 
  53         return 0;
  54 }
  55 
  56 static int __fsl_mc_device_remove(struct device *dev, void *data)
  57 {
  58         fsl_mc_device_remove(to_fsl_mc_device(dev));
  59         return 0;
  60 }
  61 
  62 /**
  63  * dprc_remove_devices - Removes devices for objects removed from a DPRC
  64  *
  65  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
  66  * @obj_desc_array: array of object descriptors for child objects currently
  67  * present in the DPRC in the MC.
  68  * @num_child_objects_in_mc: number of entries in obj_desc_array
  69  *
  70  * Synchronizes the state of the Linux bus driver with the actual state of
  71  * the MC by removing devices that represent MC objects that have
  72  * been dynamically removed in the physical DPRC.
  73  */
  74 static void dprc_remove_devices(struct fsl_mc_device *mc_bus_dev,
  75                                 struct fsl_mc_obj_desc *obj_desc_array,
  76                                 int num_child_objects_in_mc)
  77 {
  78         if (num_child_objects_in_mc != 0) {
  79                 /*
  80                  * Remove child objects that are in the DPRC in Linux,
  81                  * but not in the MC:
  82                  */
  83                 struct fsl_mc_child_objs objs;
  84 
  85                 objs.child_count = num_child_objects_in_mc;
  86                 objs.child_array = obj_desc_array;
  87                 device_for_each_child(&mc_bus_dev->dev, &objs,
  88                                       __fsl_mc_device_remove_if_not_in_mc);
  89         } else {
  90                 /*
  91                  * There are no child objects for this DPRC in the MC.
  92                  * So, remove all the child devices from Linux:
  93                  */
  94                 device_for_each_child(&mc_bus_dev->dev, NULL,
  95                                       __fsl_mc_device_remove);
  96         }
  97 }
  98 
  99 static int __fsl_mc_device_match(struct device *dev, void *data)
 100 {
 101         struct fsl_mc_obj_desc *obj_desc = data;
 102         struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
 103 
 104         return fsl_mc_device_match(mc_dev, obj_desc);
 105 }
 106 
 107 static struct fsl_mc_device *fsl_mc_device_lookup(struct fsl_mc_obj_desc
 108                                                                 *obj_desc,
 109                                                   struct fsl_mc_device
 110                                                                 *mc_bus_dev)
 111 {
 112         struct device *dev;
 113 
 114         dev = device_find_child(&mc_bus_dev->dev, obj_desc,
 115                                 __fsl_mc_device_match);
 116 
 117         return dev ? to_fsl_mc_device(dev) : NULL;
 118 }
 119 
 120 /**
 121  * check_plugged_state_change - Check change in an MC object's plugged state
 122  *
 123  * @mc_dev: pointer to the fsl-mc device for a given MC object
 124  * @obj_desc: pointer to the MC object's descriptor in the MC
 125  *
 126  * If the plugged state has changed from unplugged to plugged, the fsl-mc
 127  * device is bound to the corresponding device driver.
 128  * If the plugged state has changed from plugged to unplugged, the fsl-mc
 129  * device is unbound from the corresponding device driver.
 130  */
 131 static void check_plugged_state_change(struct fsl_mc_device *mc_dev,
 132                                        struct fsl_mc_obj_desc *obj_desc)
 133 {
 134         int error;
 135         u32 plugged_flag_at_mc =
 136                         obj_desc->state & FSL_MC_OBJ_STATE_PLUGGED;
 137 
 138         if (plugged_flag_at_mc !=
 139             (mc_dev->obj_desc.state & FSL_MC_OBJ_STATE_PLUGGED)) {
 140                 if (plugged_flag_at_mc) {
 141                         mc_dev->obj_desc.state |= FSL_MC_OBJ_STATE_PLUGGED;
 142                         error = device_attach(&mc_dev->dev);
 143                         if (error < 0) {
 144                                 dev_err(&mc_dev->dev,
 145                                         "device_attach() failed: %d\n",
 146                                         error);
 147                         }
 148                 } else {
 149                         mc_dev->obj_desc.state &= ~FSL_MC_OBJ_STATE_PLUGGED;
 150                         device_release_driver(&mc_dev->dev);
 151                 }
 152         }
 153 }
 154 
 155 /**
 156  * dprc_add_new_devices - Adds devices to the logical bus for a DPRC
 157  *
 158  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
 159  * @obj_desc_array: array of device descriptors for child devices currently
 160  * present in the physical DPRC.
 161  * @num_child_objects_in_mc: number of entries in obj_desc_array
 162  *
 163  * Synchronizes the state of the Linux bus driver with the actual
 164  * state of the MC by adding objects that have been newly discovered
 165  * in the physical DPRC.
 166  */
 167 static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
 168                                  struct fsl_mc_obj_desc *obj_desc_array,
 169                                  int num_child_objects_in_mc)
 170 {
 171         int error;
 172         int i;
 173 
 174         for (i = 0; i < num_child_objects_in_mc; i++) {
 175                 struct fsl_mc_device *child_dev;
 176                 struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];
 177 
 178                 if (strlen(obj_desc->type) == 0)
 179                         continue;
 180 
 181                 /*
 182                  * Check if device is already known to Linux:
 183                  */
 184                 child_dev = fsl_mc_device_lookup(obj_desc, mc_bus_dev);
 185                 if (child_dev) {
 186                         check_plugged_state_change(child_dev, obj_desc);
 187                         put_device(&child_dev->dev);
 188                         continue;
 189                 }
 190 
 191                 error = fsl_mc_device_add(obj_desc, NULL, &mc_bus_dev->dev,
 192                                           &child_dev);
 193                 if (error < 0)
 194                         continue;
 195         }
 196 }
 197 
 198 /**
 199  * dprc_scan_objects - Discover objects in a DPRC
 200  *
 201  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
 202  * @total_irq_count: If argument is provided the function populates the
 203  * total number of IRQs created by objects in the DPRC.
 204  *
 205  * Detects objects added and removed from a DPRC and synchronizes the
 206  * state of the Linux bus driver, MC by adding and removing
 207  * devices accordingly.
 208  * Two types of devices can be found in a DPRC: allocatable objects (e.g.,
 209  * dpbp, dpmcp) and non-allocatable devices (e.g., dprc, dpni).
 210  * All allocatable devices needed to be probed before all non-allocatable
 211  * devices, to ensure that device drivers for non-allocatable
 212  * devices can allocate any type of allocatable devices.
 213  * That is, we need to ensure that the corresponding resource pools are
 214  * populated before they can get allocation requests from probe callbacks
 215  * of the device drivers for the non-allocatable devices.
 216  */
 217 static int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
 218                              unsigned int *total_irq_count)
 219 {
 220         int num_child_objects;
 221         int dprc_get_obj_failures;
 222         int error;
 223         unsigned int irq_count = mc_bus_dev->obj_desc.irq_count;
 224         struct fsl_mc_obj_desc *child_obj_desc_array = NULL;
 225         struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
 226 
 227         error = dprc_get_obj_count(mc_bus_dev->mc_io,
 228                                    0,
 229                                    mc_bus_dev->mc_handle,
 230                                    &num_child_objects);
 231         if (error < 0) {
 232                 dev_err(&mc_bus_dev->dev, "dprc_get_obj_count() failed: %d\n",
 233                         error);
 234                 return error;
 235         }
 236 
 237         if (num_child_objects != 0) {
 238                 int i;
 239 
 240                 child_obj_desc_array =
 241                     devm_kmalloc_array(&mc_bus_dev->dev, num_child_objects,
 242                                        sizeof(*child_obj_desc_array),
 243                                        GFP_KERNEL);
 244                 if (!child_obj_desc_array)
 245                         return -ENOMEM;
 246 
 247                 /*
 248                  * Discover objects currently present in the physical DPRC:
 249                  */
 250                 dprc_get_obj_failures = 0;
 251                 for (i = 0; i < num_child_objects; i++) {
 252                         struct fsl_mc_obj_desc *obj_desc =
 253                             &child_obj_desc_array[i];
 254 
 255                         error = dprc_get_obj(mc_bus_dev->mc_io,
 256                                              0,
 257                                              mc_bus_dev->mc_handle,
 258                                              i, obj_desc);
 259                         if (error < 0) {
 260                                 dev_err(&mc_bus_dev->dev,
 261                                         "dprc_get_obj(i=%d) failed: %d\n",
 262                                         i, error);
 263                                 /*
 264                                  * Mark the obj entry as "invalid", by using the
 265                                  * empty string as obj type:
 266                                  */
 267                                 obj_desc->type[0] = '\0';
 268                                 obj_desc->id = error;
 269                                 dprc_get_obj_failures++;
 270                                 continue;
 271                         }
 272 
 273                         /*
 274                          * add a quirk for all versions of dpsec < 4.0...none
 275                          * are coherent regardless of what the MC reports.
 276                          */
 277                         if ((strcmp(obj_desc->type, "dpseci") == 0) &&
 278                             (obj_desc->ver_major < 4))
 279                                 obj_desc->flags |=
 280                                         FSL_MC_OBJ_FLAG_NO_MEM_SHAREABILITY;
 281 
 282                         irq_count += obj_desc->irq_count;
 283                         dev_dbg(&mc_bus_dev->dev,
 284                                 "Discovered object: type %s, id %d\n",
 285                                 obj_desc->type, obj_desc->id);
 286                 }
 287 
 288                 if (dprc_get_obj_failures != 0) {
 289                         dev_err(&mc_bus_dev->dev,
 290                                 "%d out of %d devices could not be retrieved\n",
 291                                 dprc_get_obj_failures, num_child_objects);
 292                 }
 293         }
 294 
 295         /*
 296          * Allocate IRQ's before binding the scanned devices with their
 297          * respective drivers.
 298          */
 299         if (dev_get_msi_domain(&mc_bus_dev->dev) && !mc_bus->irq_resources) {
 300                 if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
 301                         dev_warn(&mc_bus_dev->dev,
 302                                  "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
 303                                  irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
 304                 }
 305 
 306                 error = fsl_mc_populate_irq_pool(mc_bus,
 307                                 FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
 308                 if (error < 0)
 309                         return error;
 310         }
 311 
 312         if (total_irq_count)
 313                 *total_irq_count = irq_count;
 314 
 315         dprc_remove_devices(mc_bus_dev, child_obj_desc_array,
 316                             num_child_objects);
 317 
 318         dprc_add_new_devices(mc_bus_dev, child_obj_desc_array,
 319                              num_child_objects);
 320 
 321         if (child_obj_desc_array)
 322                 devm_kfree(&mc_bus_dev->dev, child_obj_desc_array);
 323 
 324         return 0;
 325 }
 326 
 327 /**
 328  * dprc_scan_container - Scans a physical DPRC and synchronizes Linux bus state
 329  *
 330  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
 331  *
 332  * Scans the physical DPRC and synchronizes the state of the Linux
 333  * bus driver with the actual state of the MC by adding and removing
 334  * devices as appropriate.
 335  */
 336 static int dprc_scan_container(struct fsl_mc_device *mc_bus_dev)
 337 {
 338         int error;
 339         struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
 340 
 341         fsl_mc_init_all_resource_pools(mc_bus_dev);
 342 
 343         /*
 344          * Discover objects in the DPRC:
 345          */
 346         mutex_lock(&mc_bus->scan_mutex);
 347         error = dprc_scan_objects(mc_bus_dev, NULL);
 348         mutex_unlock(&mc_bus->scan_mutex);
 349         if (error < 0) {
 350                 fsl_mc_cleanup_all_resource_pools(mc_bus_dev);
 351                 return error;
 352         }
 353 
 354         return 0;
 355 }
 356 
 357 /**
 358  * dprc_irq0_handler - Regular ISR for DPRC interrupt 0
 359  *
 360  * @irq: IRQ number of the interrupt being handled
 361  * @arg: Pointer to device structure
 362  */
 363 static irqreturn_t dprc_irq0_handler(int irq_num, void *arg)
 364 {
 365         return IRQ_WAKE_THREAD;
 366 }
 367 
 368 /**
 369  * dprc_irq0_handler_thread - Handler thread function for DPRC interrupt 0
 370  *
 371  * @irq: IRQ number of the interrupt being handled
 372  * @arg: Pointer to device structure
 373  */
 374 static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
 375 {
 376         int error;
 377         u32 status;
 378         struct device *dev = arg;
 379         struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
 380         struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
 381         struct fsl_mc_io *mc_io = mc_dev->mc_io;
 382         struct msi_desc *msi_desc = mc_dev->irqs[0]->msi_desc;
 383 
 384         dev_dbg(dev, "DPRC IRQ %d triggered on CPU %u\n",
 385                 irq_num, smp_processor_id());
 386 
 387         if (!(mc_dev->flags & FSL_MC_IS_DPRC))
 388                 return IRQ_HANDLED;
 389 
 390         mutex_lock(&mc_bus->scan_mutex);
 391         if (!msi_desc || msi_desc->irq != (u32)irq_num)
 392                 goto out;
 393 
 394         status = 0;
 395         error = dprc_get_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
 396                                     &status);
 397         if (error < 0) {
 398                 dev_err(dev,
 399                         "dprc_get_irq_status() failed: %d\n", error);
 400                 goto out;
 401         }
 402 
 403         error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
 404                                       status);
 405         if (error < 0) {
 406                 dev_err(dev,
 407                         "dprc_clear_irq_status() failed: %d\n", error);
 408                 goto out;
 409         }
 410 
 411         if (status & (DPRC_IRQ_EVENT_OBJ_ADDED |
 412                       DPRC_IRQ_EVENT_OBJ_REMOVED |
 413                       DPRC_IRQ_EVENT_CONTAINER_DESTROYED |
 414                       DPRC_IRQ_EVENT_OBJ_DESTROYED |
 415                       DPRC_IRQ_EVENT_OBJ_CREATED)) {
 416                 unsigned int irq_count;
 417 
 418                 error = dprc_scan_objects(mc_dev, &irq_count);
 419                 if (error < 0) {
 420                         /*
 421                          * If the error is -ENXIO, we ignore it, as it indicates
 422                          * that the object scan was aborted, as we detected that
 423                          * an object was removed from the DPRC in the MC, while
 424                          * we were scanning the DPRC.
 425                          */
 426                         if (error != -ENXIO) {
 427                                 dev_err(dev, "dprc_scan_objects() failed: %d\n",
 428                                         error);
 429                         }
 430 
 431                         goto out;
 432                 }
 433 
 434                 if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
 435                         dev_warn(dev,
 436                                  "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
 437                                  irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
 438                 }
 439         }
 440 
 441 out:
 442         mutex_unlock(&mc_bus->scan_mutex);
 443         return IRQ_HANDLED;
 444 }
 445 
 446 /*
 447  * Disable and clear interrupt for a given DPRC object
 448  */
 449 static int disable_dprc_irq(struct fsl_mc_device *mc_dev)
 450 {
 451         int error;
 452         struct fsl_mc_io *mc_io = mc_dev->mc_io;
 453 
 454         /*
 455          * Disable generation of interrupt, while we configure it:
 456          */
 457         error = dprc_set_irq_enable(mc_io, 0, mc_dev->mc_handle, 0, 0);
 458         if (error < 0) {
 459                 dev_err(&mc_dev->dev,
 460                         "Disabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
 461                         error);
 462                 return error;
 463         }
 464 
 465         /*
 466          * Disable all interrupt causes for the interrupt:
 467          */
 468         error = dprc_set_irq_mask(mc_io, 0, mc_dev->mc_handle, 0, 0x0);
 469         if (error < 0) {
 470                 dev_err(&mc_dev->dev,
 471                         "Disabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
 472                         error);
 473                 return error;
 474         }
 475 
 476         /*
 477          * Clear any leftover interrupts:
 478          */
 479         error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0, ~0x0U);
 480         if (error < 0) {
 481                 dev_err(&mc_dev->dev,
 482                         "Disabling DPRC IRQ failed: dprc_clear_irq_status() failed: %d\n",
 483                         error);
 484                 return error;
 485         }
 486 
 487         return 0;
 488 }
 489 
 490 static int register_dprc_irq_handler(struct fsl_mc_device *mc_dev)
 491 {
 492         int error;
 493         struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
 494 
 495         /*
 496          * NOTE: devm_request_threaded_irq() invokes the device-specific
 497          * function that programs the MSI physically in the device
 498          */
 499         error = devm_request_threaded_irq(&mc_dev->dev,
 500                                           irq->msi_desc->irq,
 501                                           dprc_irq0_handler,
 502                                           dprc_irq0_handler_thread,
 503                                           IRQF_NO_SUSPEND | IRQF_ONESHOT,
 504                                           dev_name(&mc_dev->dev),
 505                                           &mc_dev->dev);
 506         if (error < 0) {
 507                 dev_err(&mc_dev->dev,
 508                         "devm_request_threaded_irq() failed: %d\n",
 509                         error);
 510                 return error;
 511         }
 512 
 513         return 0;
 514 }
 515 
 516 static int enable_dprc_irq(struct fsl_mc_device *mc_dev)
 517 {
 518         int error;
 519 
 520         /*
 521          * Enable all interrupt causes for the interrupt:
 522          */
 523         error = dprc_set_irq_mask(mc_dev->mc_io, 0, mc_dev->mc_handle, 0,
 524                                   ~0x0u);
 525         if (error < 0) {
 526                 dev_err(&mc_dev->dev,
 527                         "Enabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
 528                         error);
 529 
 530                 return error;
 531         }
 532 
 533         /*
 534          * Enable generation of the interrupt:
 535          */
 536         error = dprc_set_irq_enable(mc_dev->mc_io, 0, mc_dev->mc_handle, 0, 1);
 537         if (error < 0) {
 538                 dev_err(&mc_dev->dev,
 539                         "Enabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
 540                         error);
 541 
 542                 return error;
 543         }
 544 
 545         return 0;
 546 }
 547 
 548 /*
 549  * Setup interrupt for a given DPRC device
 550  */
 551 static int dprc_setup_irq(struct fsl_mc_device *mc_dev)
 552 {
 553         int error;
 554 
 555         error = fsl_mc_allocate_irqs(mc_dev);
 556         if (error < 0)
 557                 return error;
 558 
 559         error = disable_dprc_irq(mc_dev);
 560         if (error < 0)
 561                 goto error_free_irqs;
 562 
 563         error = register_dprc_irq_handler(mc_dev);
 564         if (error < 0)
 565                 goto error_free_irqs;
 566 
 567         error = enable_dprc_irq(mc_dev);
 568         if (error < 0)
 569                 goto error_free_irqs;
 570 
 571         return 0;
 572 
 573 error_free_irqs:
 574         fsl_mc_free_irqs(mc_dev);
 575         return error;
 576 }
 577 
 578 /**
 579  * dprc_probe - callback invoked when a DPRC is being bound to this driver
 580  *
 581  * @mc_dev: Pointer to fsl-mc device representing a DPRC
 582  *
 583  * It opens the physical DPRC in the MC.
 584  * It scans the DPRC to discover the MC objects contained in it.
 585  * It creates the interrupt pool for the MC bus associated with the DPRC.
 586  * It configures the interrupts for the DPRC device itself.
 587  */
 588 static int dprc_probe(struct fsl_mc_device *mc_dev)
 589 {
 590         int error;
 591         size_t region_size;
 592         struct device *parent_dev = mc_dev->dev.parent;
 593         struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
 594         bool mc_io_created = false;
 595         bool msi_domain_set = false;
 596         u16 major_ver, minor_ver;
 597 
 598         if (!is_fsl_mc_bus_dprc(mc_dev))
 599                 return -EINVAL;
 600 
 601         if (dev_get_msi_domain(&mc_dev->dev))
 602                 return -EINVAL;
 603 
 604         if (!mc_dev->mc_io) {
 605                 /*
 606                  * This is a child DPRC:
 607                  */
 608                 if (!dev_is_fsl_mc(parent_dev))
 609                         return -EINVAL;
 610 
 611                 if (mc_dev->obj_desc.region_count == 0)
 612                         return -EINVAL;
 613 
 614                 region_size = resource_size(mc_dev->regions);
 615 
 616                 error = fsl_create_mc_io(&mc_dev->dev,
 617                                          mc_dev->regions[0].start,
 618                                          region_size,
 619                                          NULL,
 620                                          FSL_MC_IO_ATOMIC_CONTEXT_PORTAL,
 621                                          &mc_dev->mc_io);
 622                 if (error < 0)
 623                         return error;
 624 
 625                 mc_io_created = true;
 626 
 627                 /*
 628                  * Inherit parent MSI domain:
 629                  */
 630                 dev_set_msi_domain(&mc_dev->dev,
 631                                    dev_get_msi_domain(parent_dev));
 632                 msi_domain_set = true;
 633         } else {
 634                 /*
 635                  * This is a root DPRC
 636                  */
 637                 struct irq_domain *mc_msi_domain;
 638 
 639                 if (dev_is_fsl_mc(parent_dev))
 640                         return -EINVAL;
 641 
 642                 error = fsl_mc_find_msi_domain(parent_dev,
 643                                                &mc_msi_domain);
 644                 if (error < 0) {
 645                         dev_warn(&mc_dev->dev,
 646                                  "WARNING: MC bus without interrupt support\n");
 647                 } else {
 648                         dev_set_msi_domain(&mc_dev->dev, mc_msi_domain);
 649                         msi_domain_set = true;
 650                 }
 651         }
 652 
 653         error = dprc_open(mc_dev->mc_io, 0, mc_dev->obj_desc.id,
 654                           &mc_dev->mc_handle);
 655         if (error < 0) {
 656                 dev_err(&mc_dev->dev, "dprc_open() failed: %d\n", error);
 657                 goto error_cleanup_msi_domain;
 658         }
 659 
 660         error = dprc_get_attributes(mc_dev->mc_io, 0, mc_dev->mc_handle,
 661                                     &mc_bus->dprc_attr);
 662         if (error < 0) {
 663                 dev_err(&mc_dev->dev, "dprc_get_attributes() failed: %d\n",
 664                         error);
 665                 goto error_cleanup_open;
 666         }
 667 
 668         error = dprc_get_api_version(mc_dev->mc_io, 0,
 669                                      &major_ver,
 670                                      &minor_ver);
 671         if (error < 0) {
 672                 dev_err(&mc_dev->dev, "dprc_get_api_version() failed: %d\n",
 673                         error);
 674                 goto error_cleanup_open;
 675         }
 676 
 677         if (major_ver < DPRC_MIN_VER_MAJOR ||
 678             (major_ver == DPRC_MIN_VER_MAJOR &&
 679              minor_ver < DPRC_MIN_VER_MINOR)) {
 680                 dev_err(&mc_dev->dev,
 681                         "ERROR: DPRC version %d.%d not supported\n",
 682                         major_ver, minor_ver);
 683                 error = -ENOTSUPP;
 684                 goto error_cleanup_open;
 685         }
 686 
 687         mutex_init(&mc_bus->scan_mutex);
 688 
 689         /*
 690          * Discover MC objects in DPRC object:
 691          */
 692         error = dprc_scan_container(mc_dev);
 693         if (error < 0)
 694                 goto error_cleanup_open;
 695 
 696         /*
 697          * Configure interrupt for the DPRC object associated with this MC bus:
 698          */
 699         error = dprc_setup_irq(mc_dev);
 700         if (error < 0)
 701                 goto error_cleanup_open;
 702 
 703         dev_info(&mc_dev->dev, "DPRC device bound to driver");
 704         return 0;
 705 
 706 error_cleanup_open:
 707         (void)dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
 708 
 709 error_cleanup_msi_domain:
 710         if (msi_domain_set)
 711                 dev_set_msi_domain(&mc_dev->dev, NULL);
 712 
 713         if (mc_io_created) {
 714                 fsl_destroy_mc_io(mc_dev->mc_io);
 715                 mc_dev->mc_io = NULL;
 716         }
 717 
 718         return error;
 719 }
 720 
 721 /*
 722  * Tear down interrupt for a given DPRC object
 723  */
 724 static void dprc_teardown_irq(struct fsl_mc_device *mc_dev)
 725 {
 726         struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
 727 
 728         (void)disable_dprc_irq(mc_dev);
 729 
 730         devm_free_irq(&mc_dev->dev, irq->msi_desc->irq, &mc_dev->dev);
 731 
 732         fsl_mc_free_irqs(mc_dev);
 733 }
 734 
 735 /**
 736  * dprc_remove - callback invoked when a DPRC is being unbound from this driver
 737  *
 738  * @mc_dev: Pointer to fsl-mc device representing the DPRC
 739  *
 740  * It removes the DPRC's child objects from Linux (not from the MC) and
 741  * closes the DPRC device in the MC.
 742  * It tears down the interrupts that were configured for the DPRC device.
 743  * It destroys the interrupt pool associated with this MC bus.
 744  */
 745 static int dprc_remove(struct fsl_mc_device *mc_dev)
 746 {
 747         int error;
 748         struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
 749 
 750         if (!is_fsl_mc_bus_dprc(mc_dev))
 751                 return -EINVAL;
 752         if (!mc_dev->mc_io)
 753                 return -EINVAL;
 754 
 755         if (!mc_bus->irq_resources)
 756                 return -EINVAL;
 757 
 758         if (dev_get_msi_domain(&mc_dev->dev))
 759                 dprc_teardown_irq(mc_dev);
 760 
 761         device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
 762 
 763         if (dev_get_msi_domain(&mc_dev->dev)) {
 764                 fsl_mc_cleanup_irq_pool(mc_bus);
 765                 dev_set_msi_domain(&mc_dev->dev, NULL);
 766         }
 767 
 768         fsl_mc_cleanup_all_resource_pools(mc_dev);
 769 
 770         error = dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
 771         if (error < 0)
 772                 dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);
 773 
 774         if (!fsl_mc_is_root_dprc(&mc_dev->dev)) {
 775                 fsl_destroy_mc_io(mc_dev->mc_io);
 776                 mc_dev->mc_io = NULL;
 777         }
 778 
 779         dev_info(&mc_dev->dev, "DPRC device unbound from driver");
 780         return 0;
 781 }
 782 
 783 static const struct fsl_mc_device_id match_id_table[] = {
 784         {
 785          .vendor = FSL_MC_VENDOR_FREESCALE,
 786          .obj_type = "dprc"},
 787         {.vendor = 0x0},
 788 };
 789 
 790 static struct fsl_mc_driver dprc_driver = {
 791         .driver = {
 792                    .name = FSL_MC_DPRC_DRIVER_NAME,
 793                    .owner = THIS_MODULE,
 794                    .pm = NULL,
 795                    },
 796         .match_id_table = match_id_table,
 797         .probe = dprc_probe,
 798         .remove = dprc_remove,
 799 };
 800 
 801 int __init dprc_driver_init(void)
 802 {
 803         return fsl_mc_driver_register(&dprc_driver);
 804 }
 805 
 806 void dprc_driver_exit(void)
 807 {
 808         fsl_mc_driver_unregister(&dprc_driver);
 809 }