drivers/fpga/dfl.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Driver for FPGA Device Feature List (DFL) Support
   4  *
   5  * Copyright (C) 2017-2018 Intel Corporation, Inc.
   6  *
   7  * Authors:
   8  *   Kang Luwei <[email protected]>
   9  *   Zhang Yi <[email protected]>
  10  *   Wu Hao <[email protected]>
  11  *   Xiao Guangrong <[email protected]>
  12  */
  13 #include <linux/dfl.h>
  14 #include <linux/fpga-dfl.h>
  15 #include <linux/module.h>
  16 #include <linux/uaccess.h>
  17
  18 #include "dfl.h"
  19
  20 static DEFINE_MUTEX(dfl_id_mutex);
  21
  22 /*
  23  * when adding a new feature dev support in DFL framework, it's required to
  24  * add a new item in enum dfl_id_type and provide related information in below
  25  * dfl_devs table which is indexed by dfl_id_type, e.g. name string used for
  26  * platform device creation (define name strings in dfl.h, as they could be
  27  * reused by platform device drivers).
  28  *
  29  * if the new feature dev needs chardev support, then it's required to add
  30  * a new item in dfl_chardevs table and configure dfl_devs[i].devt_type as
  31  * index to dfl_chardevs table. If no chardev support just set devt_type
  32  * as one invalid index (DFL_FPGA_DEVT_MAX).
  33  */
  34 enum dfl_fpga_devt_type {
  35         DFL_FPGA_DEVT_FME,
  36         DFL_FPGA_DEVT_PORT,
  37         DFL_FPGA_DEVT_MAX,
  38 };
  39
  40 static struct lock_class_key dfl_pdata_keys[DFL_ID_MAX];
  41
  42 static const char *dfl_pdata_key_strings[DFL_ID_MAX] = {
  43         "dfl-fme-pdata",
  44         "dfl-port-pdata",
  45 };
  46
  47 /**
  48  * dfl_dev_info - dfl feature device information.
  49  * @name: name string of the feature platform device.
  50  * @dfh_id: id value in Device Feature Header (DFH) register by DFL spec.
  51  * @id: idr id of the feature dev.
  52  * @devt_type: index to dfl_chrdevs[].
  53  */
  54 struct dfl_dev_info {
  55         const char *name;
  56         u16 dfh_id;
  57         struct idr id;
  58         enum dfl_fpga_devt_type devt_type;
  59 };
  60
  61 /* it is indexed by dfl_id_type */
  62 static struct dfl_dev_info dfl_devs[] = {
  63         {.name = DFL_FPGA_FEATURE_DEV_FME, .dfh_id = DFH_ID_FIU_FME,
  64          .devt_type = DFL_FPGA_DEVT_FME},
  65         {.name = DFL_FPGA_FEATURE_DEV_PORT, .dfh_id = DFH_ID_FIU_PORT,
  66          .devt_type = DFL_FPGA_DEVT_PORT},
  67 };
  68
  69 /**
  70  * dfl_chardev_info - chardev information of dfl feature device
  71  * @name: nmae string of the char device.
  72  * @devt: devt of the char device.
  73  */
  74 struct dfl_chardev_info {
  75         const char *name;
  76         dev_t devt;
  77 };
  78
  79 /* indexed by enum dfl_fpga_devt_type */
  80 static struct dfl_chardev_info dfl_chrdevs[] = {
  81         {.name = DFL_FPGA_FEATURE_DEV_FME},
  82         {.name = DFL_FPGA_FEATURE_DEV_PORT},
  83 };
  84
  85 static void dfl_ids_init(void)
  86 {
  87         int i;
  88
  89         for (i = 0; i < ARRAY_SIZE(dfl_devs); i++)
  90                 idr_init(&dfl_devs[i].id);
  91 }
  92
  93 static void dfl_ids_destroy(void)
  94 {
  95         int i;
  96
  97         for (i = 0; i < ARRAY_SIZE(dfl_devs); i++)
  98                 idr_destroy(&dfl_devs[i].id);
  99 }
 100
 101 static int dfl_id_alloc(enum dfl_id_type type, struct device *dev)
 102 {
 103         int id;
 104
 105         WARN_ON(type >= DFL_ID_MAX);
 106         mutex_lock(&dfl_id_mutex);
 107         id = idr_alloc(&dfl_devs[type].id, dev, 0, 0, GFP_KERNEL);
 108         mutex_unlock(&dfl_id_mutex);
 109
 110         return id;
 111 }
 112
 113 static void dfl_id_free(enum dfl_id_type type, int id)
 114 {
 115         WARN_ON(type >= DFL_ID_MAX);
 116         mutex_lock(&dfl_id_mutex);
 117         idr_remove(&dfl_devs[type].id, id);
 118         mutex_unlock(&dfl_id_mutex);
 119 }
 120
 121 static enum dfl_id_type feature_dev_id_type(struct platform_device *pdev)
 122 {
 123         int i;
 124
 125         for (i = 0; i < ARRAY_SIZE(dfl_devs); i++)
 126                 if (!strcmp(dfl_devs[i].name, pdev->name))
 127                         return i;
 128
 129         return DFL_ID_MAX;
 130 }
 131
 132 static enum dfl_id_type dfh_id_to_type(u16 id)
 133 {
 134         int i;
 135
 136         for (i = 0; i < ARRAY_SIZE(dfl_devs); i++)
 137                 if (dfl_devs[i].dfh_id == id)
 138                         return i;
 139
 140         return DFL_ID_MAX;
 141 }
 142
 143 /*
 144  * introduce a global port_ops list, it allows port drivers to register ops
 145  * in such list, then other feature devices (e.g. FME), could use the port
 146  * functions even related port platform device is hidden. Below is one example,
 147  * in virtualization case of PCIe-based FPGA DFL device, when SRIOV is
 148  * enabled, port (and it's AFU) is turned into VF and port platform device
 149  * is hidden from system but it's still required to access port to finish FPGA
 150  * reconfiguration function in FME.
 151  */
 152
 153 static DEFINE_MUTEX(dfl_port_ops_mutex);
 154 static LIST_HEAD(dfl_port_ops_list);
 155
 156 /**
 157  * dfl_fpga_port_ops_get - get matched port ops from the global list
 158  * @pdev: platform device to match with associated port ops.
 159  * Return: matched port ops on success, NULL otherwise.
 160  *
 161  * Please note that must dfl_fpga_port_ops_put after use the port_ops.
 162  */
 163 struct dfl_fpga_port_ops *dfl_fpga_port_ops_get(struct platform_device *pdev)
 164 {
 165         struct dfl_fpga_port_ops *ops = NULL;
 166
 167         mutex_lock(&dfl_port_ops_mutex);
 168         if (list_empty(&dfl_port_ops_list))
 169                 goto done;
 170
 171         list_for_each_entry(ops, &dfl_port_ops_list, node) {
 172                 /* match port_ops using the name of platform device */
 173                 if (!strcmp(pdev->name, ops->name)) {
 174                         if (!try_module_get(ops->owner))
 175                                 ops = NULL;
 176                         goto done;
 177                 }
 178         }
 179
 180         ops = NULL;
 181 done:
 182         mutex_unlock(&dfl_port_ops_mutex);
 183         return ops;
 184 }
 185 EXPORT_SYMBOL_GPL(dfl_fpga_port_ops_get);
 186
 187 /**
 188  * dfl_fpga_port_ops_put - put port ops
 189  * @ops: port ops.
 190  */
 191 void dfl_fpga_port_ops_put(struct dfl_fpga_port_ops *ops)
 192 {
 193         if (ops && ops->owner)
 194                 module_put(ops->owner);
 195 }
 196 EXPORT_SYMBOL_GPL(dfl_fpga_port_ops_put);
 197
 198 /**
 199  * dfl_fpga_port_ops_add - add port_ops to global list
 200  * @ops: port ops to add.
 201  */
 202 void dfl_fpga_port_ops_add(struct dfl_fpga_port_ops *ops)
 203 {
 204         mutex_lock(&dfl_port_ops_mutex);
 205         list_add_tail(&ops->node, &dfl_port_ops_list);
 206         mutex_unlock(&dfl_port_ops_mutex);
 207 }
 208 EXPORT_SYMBOL_GPL(dfl_fpga_port_ops_add);
 209
 210 /**
 211  * dfl_fpga_port_ops_del - remove port_ops from global list
 212  * @ops: port ops to del.
 213  */
 214 void dfl_fpga_port_ops_del(struct dfl_fpga_port_ops *ops)
 215 {
 216         mutex_lock(&dfl_port_ops_mutex);
 217         list_del(&ops->node);
 218         mutex_unlock(&dfl_port_ops_mutex);
 219 }
 220 EXPORT_SYMBOL_GPL(dfl_fpga_port_ops_del);
 221
 222 /**
 223  * dfl_fpga_check_port_id - check the port id
 224  * @pdev: port platform device.
 225  * @pport_id: port id to compare.
 226  *
 227  * Return: 1 if port device matches with given port id, otherwise 0.
 228  */
 229 int dfl_fpga_check_port_id(struct platform_device *pdev, void *pport_id)
 230 {
 231         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 232         struct dfl_fpga_port_ops *port_ops;
 233
 234         if (pdata->id != FEATURE_DEV_ID_UNUSED)
 235                 return pdata->id == *(int *)pport_id;
 236
 237         port_ops = dfl_fpga_port_ops_get(pdev);
 238         if (!port_ops || !port_ops->get_id)
 239                 return 0;
 240
 241         pdata->id = port_ops->get_id(pdev);
 242         dfl_fpga_port_ops_put(port_ops);
 243
 244         return pdata->id == *(int *)pport_id;
 245 }
 246 EXPORT_SYMBOL_GPL(dfl_fpga_check_port_id);
 247
 248 static DEFINE_IDA(dfl_device_ida);
 249
 250 static const struct dfl_device_id *
 251 dfl_match_one_device(const struct dfl_device_id *id, struct dfl_device *ddev)
 252 {
 253         if (id->type == ddev->type && id->feature_id == ddev->feature_id)
 254                 return id;
 255
 256         return NULL;
 257 }
 258
 259 static int dfl_bus_match(struct device *dev, struct device_driver *drv)
 260 {
 261         struct dfl_device *ddev = to_dfl_dev(dev);
 262         struct dfl_driver *ddrv = to_dfl_drv(drv);
 263         const struct dfl_device_id *id_entry;
 264
 265         id_entry = ddrv->id_table;
 266         if (id_entry) {
 267                 while (id_entry->feature_id) {
 268                         if (dfl_match_one_device(id_entry, ddev)) {
 269                                 ddev->id_entry = id_entry;
 270                                 return 1;
 271                         }
 272                         id_entry++;
 273                 }
 274         }
 275
 276         return 0;
 277 }
 278
 279 static int dfl_bus_probe(struct device *dev)
 280 {
 281         struct dfl_driver *ddrv = to_dfl_drv(dev->driver);
 282         struct dfl_device *ddev = to_dfl_dev(dev);
 283
 284         return ddrv->probe(ddev);
 285 }
 286
 287 static void dfl_bus_remove(struct device *dev)
 288 {
 289         struct dfl_driver *ddrv = to_dfl_drv(dev->driver);
 290         struct dfl_device *ddev = to_dfl_dev(dev);
 291
 292         if (ddrv->remove)
 293                 ddrv->remove(ddev);
 294 }
 295
 296 static int dfl_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
 297 {
 298         struct dfl_device *ddev = to_dfl_dev(dev);
 299
 300         return add_uevent_var(env, "MODALIAS=dfl:t%04Xf%04X",
 301                               ddev->type, ddev->feature_id);
 302 }
 303
 304 static ssize_t
 305 type_show(struct device *dev, struct device_attribute *attr, char *buf)
 306 {
 307         struct dfl_device *ddev = to_dfl_dev(dev);
 308
 309         return sprintf(buf, "0x%x\n", ddev->type);
 310 }
 311 static DEVICE_ATTR_RO(type);
 312
 313 static ssize_t
 314 feature_id_show(struct device *dev, struct device_attribute *attr, char *buf)
 315 {
 316         struct dfl_device *ddev = to_dfl_dev(dev);
 317
 318         return sprintf(buf, "0x%x\n", ddev->feature_id);
 319 }
 320 static DEVICE_ATTR_RO(feature_id);
 321
 322 static struct attribute *dfl_dev_attrs[] = {
 323         &dev_attr_type.attr,
 324         &dev_attr_feature_id.attr,
 325         NULL,
 326 };
 327 ATTRIBUTE_GROUPS(dfl_dev);
 328
 329 static struct bus_type dfl_bus_type = {
 330         .name           = "dfl",
 331         .match          = dfl_bus_match,
 332         .probe          = dfl_bus_probe,
 333         .remove         = dfl_bus_remove,
 334         .uevent         = dfl_bus_uevent,
 335         .dev_groups     = dfl_dev_groups,
 336 };
 337
 338 static void release_dfl_dev(struct device *dev)
 339 {
 340         struct dfl_device *ddev = to_dfl_dev(dev);
 341
 342         if (ddev->mmio_res.parent)
 343                 release_resource(&ddev->mmio_res);
 344
 345         ida_simple_remove(&dfl_device_ida, ddev->id);
 346         kfree(ddev->irqs);
 347         kfree(ddev);
 348 }
 349
 350 static struct dfl_device *
 351 dfl_dev_add(struct dfl_feature_platform_data *pdata,
 352             struct dfl_feature *feature)
 353 {
 354         struct platform_device *pdev = pdata->dev;
 355         struct resource *parent_res;
 356         struct dfl_device *ddev;
 357         int id, i, ret;
 358
 359         ddev = kzalloc(sizeof(*ddev), GFP_KERNEL);
 360         if (!ddev)
 361                 return ERR_PTR(-ENOMEM);
 362
 363         id = ida_simple_get(&dfl_device_ida, 0, 0, GFP_KERNEL);
 364         if (id < 0) {
 365                 dev_err(&pdev->dev, "unable to get id\n");
 366                 kfree(ddev);
 367                 return ERR_PTR(id);
 368         }
 369
 370         /* freeing resources by put_device() after device_initialize() */
 371         device_initialize(&ddev->dev);
 372         ddev->dev.parent = &pdev->dev;
 373         ddev->dev.bus = &dfl_bus_type;
 374         ddev->dev.release = release_dfl_dev;
 375         ddev->id = id;
 376         ret = dev_set_name(&ddev->dev, "dfl_dev.%d", id);
 377         if (ret)
 378                 goto put_dev;
 379
 380         ddev->type = feature_dev_id_type(pdev);
 381         ddev->feature_id = feature->id;
 382         ddev->revision = feature->revision;
 383         ddev->cdev = pdata->dfl_cdev;
 384
 385         /* add mmio resource */
 386         parent_res = &pdev->resource[feature->resource_index];
 387         ddev->mmio_res.flags = IORESOURCE_MEM;
 388         ddev->mmio_res.start = parent_res->start;
 389         ddev->mmio_res.end = parent_res->end;
 390         ddev->mmio_res.name = dev_name(&ddev->dev);
 391         ret = insert_resource(parent_res, &ddev->mmio_res);
 392         if (ret) {
 393                 dev_err(&pdev->dev, "%s failed to claim resource: %pR\n",
 394                         dev_name(&ddev->dev), &ddev->mmio_res);
 395                 goto put_dev;
 396         }
 397
 398         /* then add irq resource */
 399         if (feature->nr_irqs) {
 400                 ddev->irqs = kcalloc(feature->nr_irqs,
 401                                      sizeof(*ddev->irqs), GFP_KERNEL);
 402                 if (!ddev->irqs) {
 403                         ret = -ENOMEM;
 404                         goto put_dev;
 405                 }
 406
 407                 for (i = 0; i < feature->nr_irqs; i++)
 408                         ddev->irqs[i] = feature->irq_ctx[i].irq;
 409
 410                 ddev->num_irqs = feature->nr_irqs;
 411         }
 412
 413         ret = device_add(&ddev->dev);
 414         if (ret)
 415                 goto put_dev;
 416
 417         dev_dbg(&pdev->dev, "add dfl_dev: %s\n", dev_name(&ddev->dev));
 418         return ddev;
 419
 420 put_dev:
 421         /* calls release_dfl_dev() which does the clean up  */
 422         put_device(&ddev->dev);
 423         return ERR_PTR(ret);
 424 }
 425
 426 static void dfl_devs_remove(struct dfl_feature_platform_data *pdata)
 427 {
 428         struct dfl_feature *feature;
 429
 430         dfl_fpga_dev_for_each_feature(pdata, feature) {
 431                 if (feature->ddev) {
 432                         device_unregister(&feature->ddev->dev);
 433                         feature->ddev = NULL;
 434                 }
 435         }
 436 }
 437
 438 static int dfl_devs_add(struct dfl_feature_platform_data *pdata)
 439 {
 440         struct dfl_feature *feature;
 441         struct dfl_device *ddev;
 442         int ret;
 443
 444         dfl_fpga_dev_for_each_feature(pdata, feature) {
 445                 if (feature->ioaddr)
 446                         continue;
 447
 448                 if (feature->ddev) {
 449                         ret = -EEXIST;
 450                         goto err;
 451                 }
 452
 453                 ddev = dfl_dev_add(pdata, feature);
 454                 if (IS_ERR(ddev)) {
 455                         ret = PTR_ERR(ddev);
 456                         goto err;
 457                 }
 458
 459                 feature->ddev = ddev;
 460         }
 461
 462         return 0;
 463
 464 err:
 465         dfl_devs_remove(pdata);
 466         return ret;
 467 }
 468
 469 int __dfl_driver_register(struct dfl_driver *dfl_drv, struct module *owner)
 470 {
 471         if (!dfl_drv || !dfl_drv->probe || !dfl_drv->id_table)
 472                 return -EINVAL;
 473
 474         dfl_drv->drv.owner = owner;
 475         dfl_drv->drv.bus = &dfl_bus_type;
 476
 477         return driver_register(&dfl_drv->drv);
 478 }
 479 EXPORT_SYMBOL(__dfl_driver_register);
 480
 481 void dfl_driver_unregister(struct dfl_driver *dfl_drv)
 482 {
 483         driver_unregister(&dfl_drv->drv);
 484 }
 485 EXPORT_SYMBOL(dfl_driver_unregister);
 486
 487 #define is_header_feature(feature) ((feature)->id == FEATURE_ID_FIU_HEADER)
 488
 489 /**
 490  * dfl_fpga_dev_feature_uinit - uinit for sub features of dfl feature device
 491  * @pdev: feature device.
 492  */
 493 void dfl_fpga_dev_feature_uinit(struct platform_device *pdev)
 494 {
 495         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 496         struct dfl_feature *feature;
 497
 498         dfl_devs_remove(pdata);
 499
 500         dfl_fpga_dev_for_each_feature(pdata, feature) {
 501                 if (feature->ops) {
 502                         if (feature->ops->uinit)
 503                                 feature->ops->uinit(pdev, feature);
 504                         feature->ops = NULL;
 505                 }
 506         }
 507 }
 508 EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_uinit);
 509
 510 static int dfl_feature_instance_init(struct platform_device *pdev,
 511                                      struct dfl_feature_platform_data *pdata,
 512                                      struct dfl_feature *feature,
 513                                      struct dfl_feature_driver *drv)
 514 {
 515         void __iomem *base;
 516         int ret = 0;
 517
 518         if (!is_header_feature(feature)) {
 519                 base = devm_platform_ioremap_resource(pdev,
 520                                                       feature->resource_index);
 521                 if (IS_ERR(base)) {
 522                         dev_err(&pdev->dev,
 523                                 "ioremap failed for feature 0x%x!\n",
 524                                 feature->id);
 525                         return PTR_ERR(base);
 526                 }
 527
 528                 feature->ioaddr = base;
 529         }
 530
 531         if (drv->ops->init) {
 532                 ret = drv->ops->init(pdev, feature);
 533                 if (ret)
 534                         return ret;
 535         }
 536
 537         feature->ops = drv->ops;
 538
 539         return ret;
 540 }
 541
 542 static bool dfl_feature_drv_match(struct dfl_feature *feature,
 543                                   struct dfl_feature_driver *driver)
 544 {
 545         const struct dfl_feature_id *ids = driver->id_table;
 546
 547         if (ids) {
 548                 while (ids->id) {
 549                         if (ids->id == feature->id)
 550                                 return true;
 551                         ids++;
 552                 }
 553         }
 554         return false;
 555 }
 556
 557 /**
 558  * dfl_fpga_dev_feature_init - init for sub features of dfl feature device
 559  * @pdev: feature device.
 560  * @feature_drvs: drvs for sub features.
 561  *
 562  * This function will match sub features with given feature drvs list and
 563  * use matched drv to init related sub feature.
 564  *
 565  * Return: 0 on success, negative error code otherwise.
 566  */
 567 int dfl_fpga_dev_feature_init(struct platform_device *pdev,
 568                               struct dfl_feature_driver *feature_drvs)
 569 {
 570         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 571         struct dfl_feature_driver *drv = feature_drvs;
 572         struct dfl_feature *feature;
 573         int ret;
 574
 575         while (drv->ops) {
 576                 dfl_fpga_dev_for_each_feature(pdata, feature) {
 577                         if (dfl_feature_drv_match(feature, drv)) {
 578                                 ret = dfl_feature_instance_init(pdev, pdata,
 579                                                                 feature, drv);
 580                                 if (ret)
 581                                         goto exit;
 582                         }
 583                 }
 584                 drv++;
 585         }
 586
 587         ret = dfl_devs_add(pdata);
 588         if (ret)
 589                 goto exit;
 590
 591         return 0;
 592 exit:
 593         dfl_fpga_dev_feature_uinit(pdev);
 594         return ret;
 595 }
 596 EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init);
 597
 598 static void dfl_chardev_uinit(void)
 599 {
 600         int i;
 601
 602         for (i = 0; i < DFL_FPGA_DEVT_MAX; i++)
 603                 if (MAJOR(dfl_chrdevs[i].devt)) {
 604                         unregister_chrdev_region(dfl_chrdevs[i].devt,
 605                                                  MINORMASK + 1);
 606                         dfl_chrdevs[i].devt = MKDEV(0, 0);
 607                 }
 608 }
 609
 610 static int dfl_chardev_init(void)
 611 {
 612         int i, ret;
 613
 614         for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) {
 615                 ret = alloc_chrdev_region(&dfl_chrdevs[i].devt, 0,
 616                                           MINORMASK + 1, dfl_chrdevs[i].name);
 617                 if (ret)
 618                         goto exit;
 619         }
 620
 621         return 0;
 622
 623 exit:
 624         dfl_chardev_uinit();
 625         return ret;
 626 }
 627
 628 static dev_t dfl_get_devt(enum dfl_fpga_devt_type type, int id)
 629 {
 630         if (type >= DFL_FPGA_DEVT_MAX)
 631                 return 0;
 632
 633         return MKDEV(MAJOR(dfl_chrdevs[type].devt), id);
 634 }
 635
 636 /**
 637  * dfl_fpga_dev_ops_register - register cdev ops for feature dev
 638  *
 639  * @pdev: feature dev.
 640  * @fops: file operations for feature dev's cdev.
 641  * @owner: owning module/driver.
 642  *
 643  * Return: 0 on success, negative error code otherwise.
 644  */
 645 int dfl_fpga_dev_ops_register(struct platform_device *pdev,
 646                               const struct file_operations *fops,
 647                               struct module *owner)
 648 {
 649         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 650
 651         cdev_init(&pdata->cdev, fops);
 652         pdata->cdev.owner = owner;
 653
 654         /*
 655          * set parent to the feature device so that its refcount is
 656          * decreased after the last refcount of cdev is gone, that
 657          * makes sure the feature device is valid during device
 658          * file's life-cycle.
 659          */
 660         pdata->cdev.kobj.parent = &pdev->dev.kobj;
 661
 662         return cdev_add(&pdata->cdev, pdev->dev.devt, 1);
 663 }
 664 EXPORT_SYMBOL_GPL(dfl_fpga_dev_ops_register);
 665
 666 /**
 667  * dfl_fpga_dev_ops_unregister - unregister cdev ops for feature dev
 668  * @pdev: feature dev.
 669  */
 670 void dfl_fpga_dev_ops_unregister(struct platform_device *pdev)
 671 {
 672         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
 673
 674         cdev_del(&pdata->cdev);
 675 }
 676 EXPORT_SYMBOL_GPL(dfl_fpga_dev_ops_unregister);
 677
 678 /**
 679  * struct build_feature_devs_info - info collected during feature dev build.
 680  *
 681  * @dev: device to enumerate.
 682  * @cdev: the container device for all feature devices.
 683  * @nr_irqs: number of irqs for all feature devices.
 684  * @irq_table: Linux IRQ numbers for all irqs, indexed by local irq index of
 685  *             this device.
 686  * @feature_dev: current feature device.
 687  * @ioaddr: header register region address of current FIU in enumeration.
 688  * @start: register resource start of current FIU.
 689  * @len: max register resource length of current FIU.
 690  * @sub_features: a sub features linked list for feature device in enumeration.
 691  * @feature_num: number of sub features for feature device in enumeration.
 692  */
 693 struct build_feature_devs_info {
 694         struct device *dev;
 695         struct dfl_fpga_cdev *cdev;
 696         unsigned int nr_irqs;
 697         int *irq_table;
 698
 699         struct platform_device *feature_dev;
 700         void __iomem *ioaddr;
 701         resource_size_t start;
 702         resource_size_t len;
 703         struct list_head sub_features;
 704         int feature_num;
 705 };
 706
 707 /**
 708  * struct dfl_feature_info - sub feature info collected during feature dev build
 709  *
 710  * @fid: id of this sub feature.
 711  * @mmio_res: mmio resource of this sub feature.
 712  * @ioaddr: mapped base address of mmio resource.
 713  * @node: node in sub_features linked list.
 714  * @irq_base: start of irq index in this sub feature.
 715  * @nr_irqs: number of irqs of this sub feature.
 716  */
 717 struct dfl_feature_info {
 718         u16 fid;
 719         u8 revision;
 720         struct resource mmio_res;
 721         void __iomem *ioaddr;
 722         struct list_head node;
 723         unsigned int irq_base;
 724         unsigned int nr_irqs;
 725 };
 726
 727 static void dfl_fpga_cdev_add_port_dev(struct dfl_fpga_cdev *cdev,
 728                                        struct platform_device *port)
 729 {
 730         struct dfl_feature_platform_data *pdata = dev_get_platdata(&port->dev);
 731
 732         mutex_lock(&cdev->lock);
 733         list_add(&pdata->node, &cdev->port_dev_list);
 734         get_device(&pdata->dev->dev);
 735         mutex_unlock(&cdev->lock);
 736 }
 737
 738 /*
 739  * register current feature device, it is called when we need to switch to
 740  * another feature parsing or we have parsed all features on given device
 741  * feature list.
 742  */
 743 static int build_info_commit_dev(struct build_feature_devs_info *binfo)
 744 {
 745         struct platform_device *fdev = binfo->feature_dev;
 746         struct dfl_feature_platform_data *pdata;
 747         struct dfl_feature_info *finfo, *p;
 748         enum dfl_id_type type;
 749         int ret, index = 0, res_idx = 0;
 750
 751         type = feature_dev_id_type(fdev);
 752         if (WARN_ON_ONCE(type >= DFL_ID_MAX))
 753                 return -EINVAL;
 754
 755         /*
 756          * we do not need to care for the memory which is associated with
 757          * the platform device. After calling platform_device_unregister(),
 758          * it will be automatically freed by device's release() callback,
 759          * platform_device_release().
 760          */
 761         pdata = kzalloc(struct_size(pdata, features, binfo->feature_num), GFP_KERNEL);
 762         if (!pdata)
 763                 return -ENOMEM;
 764
 765         pdata->dev = fdev;
 766         pdata->num = binfo->feature_num;
 767         pdata->dfl_cdev = binfo->cdev;
 768         pdata->id = FEATURE_DEV_ID_UNUSED;
 769         mutex_init(&pdata->lock);
 770         lockdep_set_class_and_name(&pdata->lock, &dfl_pdata_keys[type],
 771                                    dfl_pdata_key_strings[type]);
 772
 773         /*
 774          * the count should be initialized to 0 to make sure
 775          *__fpga_port_enable() following __fpga_port_disable()
 776          * works properly for port device.
 777          * and it should always be 0 for fme device.
 778          */
 779         WARN_ON(pdata->disable_count);
 780
 781         fdev->dev.platform_data = pdata;
 782
 783         /* each sub feature has one MMIO resource */
 784         fdev->num_resources = binfo->feature_num;
 785         fdev->resource = kcalloc(binfo->feature_num, sizeof(*fdev->resource),
 786                                  GFP_KERNEL);
 787         if (!fdev->resource)
 788                 return -ENOMEM;
 789
 790         /* fill features and resource information for feature dev */
 791         list_for_each_entry_safe(finfo, p, &binfo->sub_features, node) {
 792                 struct dfl_feature *feature = &pdata->features[index++];
 793                 struct dfl_feature_irq_ctx *ctx;
 794                 unsigned int i;
 795
 796                 /* save resource information for each feature */
 797                 feature->dev = fdev;
 798                 feature->id = finfo->fid;
 799                 feature->revision = finfo->revision;
 800
 801                 /*
 802                  * the FIU header feature has some fundamental functions (sriov
 803                  * set, port enable/disable) needed for the dfl bus device and
 804                  * other sub features. So its mmio resource should be mapped by
 805                  * DFL bus device. And we should not assign it to feature
 806                  * devices (dfl-fme/afu) again.
 807                  */
 808                 if (is_header_feature(feature)) {
 809                         feature->resource_index = -1;
 810                         feature->ioaddr =
 811                                 devm_ioremap_resource(binfo->dev,
 812                                                       &finfo->mmio_res);
 813                         if (IS_ERR(feature->ioaddr))
 814                                 return PTR_ERR(feature->ioaddr);
 815                 } else {
 816                         feature->resource_index = res_idx;
 817                         fdev->resource[res_idx++] = finfo->mmio_res;
 818                 }
 819
 820                 if (finfo->nr_irqs) {
 821                         ctx = devm_kcalloc(binfo->dev, finfo->nr_irqs,
 822                                            sizeof(*ctx), GFP_KERNEL);
 823                         if (!ctx)
 824                                 return -ENOMEM;
 825
 826                         for (i = 0; i < finfo->nr_irqs; i++)
 827                                 ctx[i].irq =
 828                                         binfo->irq_table[finfo->irq_base + i];
 829
 830                         feature->irq_ctx = ctx;
 831                         feature->nr_irqs = finfo->nr_irqs;
 832                 }
 833
 834                 list_del(&finfo->node);
 835                 kfree(finfo);
 836         }
 837
 838         ret = platform_device_add(binfo->feature_dev);
 839         if (!ret) {
 840                 if (type == PORT_ID)
 841                         dfl_fpga_cdev_add_port_dev(binfo->cdev,
 842                                                    binfo->feature_dev);
 843                 else
 844                         binfo->cdev->fme_dev =
 845                                         get_device(&binfo->feature_dev->dev);
 846                 /*
 847                  * reset it to avoid build_info_free() freeing their resource.
 848                  *
 849                  * The resource of successfully registered feature devices
 850                  * will be freed by platform_device_unregister(). See the
 851                  * comments in build_info_create_dev().
 852                  */
 853                 binfo->feature_dev = NULL;
 854         }
 855
 856         return ret;
 857 }
 858
 859 static int
 860 build_info_create_dev(struct build_feature_devs_info *binfo,
 861                       enum dfl_id_type type)
 862 {
 863         struct platform_device *fdev;
 864
 865         if (type >= DFL_ID_MAX)
 866                 return -EINVAL;
 867
 868         /*
 869          * we use -ENODEV as the initialization indicator which indicates
 870          * whether the id need to be reclaimed
 871          */
 872         fdev = platform_device_alloc(dfl_devs[type].name, -ENODEV);
 873         if (!fdev)
 874                 return -ENOMEM;
 875
 876         binfo->feature_dev = fdev;
 877         binfo->feature_num = 0;
 878
 879         INIT_LIST_HEAD(&binfo->sub_features);
 880
 881         fdev->id = dfl_id_alloc(type, &fdev->dev);
 882         if (fdev->id < 0)
 883                 return fdev->id;
 884
 885         fdev->dev.parent = &binfo->cdev->region->dev;
 886         fdev->dev.devt = dfl_get_devt(dfl_devs[type].devt_type, fdev->id);
 887
 888         return 0;
 889 }
 890
 891 static void build_info_free(struct build_feature_devs_info *binfo)
 892 {
 893         struct dfl_feature_info *finfo, *p;
 894
 895         /*
 896          * it is a valid id, free it. See comments in
 897          * build_info_create_dev()
 898          */
 899         if (binfo->feature_dev && binfo->feature_dev->id >= 0) {
 900                 dfl_id_free(feature_dev_id_type(binfo->feature_dev),
 901                             binfo->feature_dev->id);
 902
 903                 list_for_each_entry_safe(finfo, p, &binfo->sub_features, node) {
 904                         list_del(&finfo->node);
 905                         kfree(finfo);
 906                 }
 907         }
 908
 909         platform_device_put(binfo->feature_dev);
 910
 911         devm_kfree(binfo->dev, binfo);
 912 }
 913
 914 static inline u32 feature_size(u64 value)
 915 {
 916         u32 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, value);
 917         /* workaround for private features with invalid size, use 4K instead */
 918         return ofst ? ofst : 4096;
 919 }
 920
 921 static u16 feature_id(u64 value)
 922 {
 923         u16 id = FIELD_GET(DFH_ID, value);
 924         u8 type = FIELD_GET(DFH_TYPE, value);
 925
 926         if (type == DFH_TYPE_FIU)
 927                 return FEATURE_ID_FIU_HEADER;
 928         else if (type == DFH_TYPE_PRIVATE)
 929                 return id;
 930         else if (type == DFH_TYPE_AFU)
 931                 return FEATURE_ID_AFU;
 932
 933         WARN_ON(1);
 934         return 0;
 935 }
 936
 937 static int parse_feature_irqs(struct build_feature_devs_info *binfo,
 938                               resource_size_t ofst, u16 fid,
 939                               unsigned int *irq_base, unsigned int *nr_irqs)
 940 {
 941         void __iomem *base = binfo->ioaddr + ofst;
 942         unsigned int i, ibase, inr = 0;
 943         int virq;
 944         u64 v;
 945
 946         /*
 947          * Ideally DFL framework should only read info from DFL header, but
 948          * current version DFL only provides mmio resources information for
 949          * each feature in DFL Header, no field for interrupt resources.
 950          * Interrupt resource information is provided by specific mmio
 951          * registers of each private feature which supports interrupt. So in
 952          * order to parse and assign irq resources, DFL framework has to look
 953          * into specific capability registers of these private features.
 954          *
 955          * Once future DFL version supports generic interrupt resource
 956          * information in common DFL headers, the generic interrupt parsing
 957          * code will be added. But in order to be compatible to old version
 958          * DFL, the driver may still fall back to these quirks.
 959          */
 960         switch (fid) {
 961         case PORT_FEATURE_ID_UINT:
 962                 v = readq(base + PORT_UINT_CAP);
 963                 ibase = FIELD_GET(PORT_UINT_CAP_FST_VECT, v);
 964                 inr = FIELD_GET(PORT_UINT_CAP_INT_NUM, v);
 965                 break;
 966         case PORT_FEATURE_ID_ERROR:
 967                 v = readq(base + PORT_ERROR_CAP);
 968                 ibase = FIELD_GET(PORT_ERROR_CAP_INT_VECT, v);
 969                 inr = FIELD_GET(PORT_ERROR_CAP_SUPP_INT, v);
 970                 break;
 971         case FME_FEATURE_ID_GLOBAL_ERR:
 972                 v = readq(base + FME_ERROR_CAP);
 973                 ibase = FIELD_GET(FME_ERROR_CAP_INT_VECT, v);
 974                 inr = FIELD_GET(FME_ERROR_CAP_SUPP_INT, v);
 975                 break;
 976         }
 977
 978         if (!inr) {
 979                 *irq_base = 0;
 980                 *nr_irqs = 0;
 981                 return 0;
 982         }
 983
 984         dev_dbg(binfo->dev, "feature: 0x%x, irq_base: %u, nr_irqs: %u\n",
 985                 fid, ibase, inr);
 986
 987         if (ibase + inr > binfo->nr_irqs) {
 988                 dev_err(binfo->dev,
 989                         "Invalid interrupt number in feature 0x%x\n", fid);
 990                 return -EINVAL;
 991         }
 992
 993         for (i = 0; i < inr; i++) {
 994                 virq = binfo->irq_table[ibase + i];
 995                 if (virq < 0 || virq > NR_IRQS) {
 996                         dev_err(binfo->dev,
 997                                 "Invalid irq table entry for feature 0x%x\n",
 998                                 fid);
 999                         return -EINVAL;
1000                 }
1001         }
1002
1003         *irq_base = ibase;
1004         *nr_irqs = inr;
1005
1006         return 0;
1007 }
1008
1009 /*
1010  * when create sub feature instances, for private features, it doesn't need
1011  * to provide resource size and feature id as they could be read from DFH
1012  * register. For afu sub feature, its register region only contains user
1013  * defined registers, so never trust any information from it, just use the
1014  * resource size information provided by its parent FIU.
1015  */
1016 static int
1017 create_feature_instance(struct build_feature_devs_info *binfo,
1018                         resource_size_t ofst, resource_size_t size, u16 fid)
1019 {
1020         unsigned int irq_base, nr_irqs;
1021         struct dfl_feature_info *finfo;
1022         u8 revision = 0;
1023         int ret;
1024         u64 v;
1025
1026         if (fid != FEATURE_ID_AFU) {
1027                 v = readq(binfo->ioaddr + ofst);
1028                 revision = FIELD_GET(DFH_REVISION, v);
1029
1030                 /* read feature size and id if inputs are invalid */
1031                 size = size ? size : feature_size(v);
1032                 fid = fid ? fid : feature_id(v);
1033         }
1034
1035         if (binfo->len - ofst < size)
1036                 return -EINVAL;
1037
1038         ret = parse_feature_irqs(binfo, ofst, fid, &irq_base, &nr_irqs);
1039         if (ret)
1040                 return ret;
1041
1042         finfo = kzalloc(sizeof(*finfo), GFP_KERNEL);
1043         if (!finfo)
1044                 return -ENOMEM;
1045
1046         finfo->fid = fid;
1047         finfo->revision = revision;
1048         finfo->mmio_res.start = binfo->start + ofst;
1049         finfo->mmio_res.end = finfo->mmio_res.start + size - 1;
1050         finfo->mmio_res.flags = IORESOURCE_MEM;
1051         finfo->irq_base = irq_base;
1052         finfo->nr_irqs = nr_irqs;
1053
1054         list_add_tail(&finfo->node, &binfo->sub_features);
1055         binfo->feature_num++;
1056
1057         return 0;
1058 }
1059
1060 static int parse_feature_port_afu(struct build_feature_devs_info *binfo,
1061                                   resource_size_t ofst)
1062 {
1063         u64 v = readq(binfo->ioaddr + PORT_HDR_CAP);
1064         u32 size = FIELD_GET(PORT_CAP_MMIO_SIZE, v) << 10;
1065
1066         WARN_ON(!size);
1067
1068         return create_feature_instance(binfo, ofst, size, FEATURE_ID_AFU);
1069 }
1070
1071 #define is_feature_dev_detected(binfo) (!!(binfo)->feature_dev)
1072
1073 static int parse_feature_afu(struct build_feature_devs_info *binfo,
1074                              resource_size_t ofst)
1075 {
1076         if (!is_feature_dev_detected(binfo)) {
1077                 dev_err(binfo->dev, "this AFU does not belong to any FIU.\n");
1078                 return -EINVAL;
1079         }
1080
1081         switch (feature_dev_id_type(binfo->feature_dev)) {
1082         case PORT_ID:
1083                 return parse_feature_port_afu(binfo, ofst);
1084         default:
1085                 dev_info(binfo->dev, "AFU belonging to FIU %s is not supported yet.\n",
1086                          binfo->feature_dev->name);
1087         }
1088
1089         return 0;
1090 }
1091
1092 static int build_info_prepare(struct build_feature_devs_info *binfo,
1093                               resource_size_t start, resource_size_t len)
1094 {
1095         struct device *dev = binfo->dev;
1096         void __iomem *ioaddr;
1097
1098         if (!devm_request_mem_region(dev, start, len, dev_name(dev))) {
1099                 dev_err(dev, "request region fail, start:%pa, len:%pa\n",
1100                         &start, &len);
1101                 return -EBUSY;
1102         }
1103
1104         ioaddr = devm_ioremap(dev, start, len);
1105         if (!ioaddr) {
1106                 dev_err(dev, "ioremap region fail, start:%pa, len:%pa\n",
1107                         &start, &len);
1108                 return -ENOMEM;
1109         }
1110
1111         binfo->start = start;
1112         binfo->len = len;
1113         binfo->ioaddr = ioaddr;
1114
1115         return 0;
1116 }
1117
1118 static void build_info_complete(struct build_feature_devs_info *binfo)
1119 {
1120         devm_iounmap(binfo->dev, binfo->ioaddr);
1121         devm_release_mem_region(binfo->dev, binfo->start, binfo->len);
1122 }
1123
1124 static int parse_feature_fiu(struct build_feature_devs_info *binfo,
1125                              resource_size_t ofst)
1126 {
1127         int ret = 0;
1128         u32 offset;
1129         u16 id;
1130         u64 v;
1131
1132         if (is_feature_dev_detected(binfo)) {
1133                 build_info_complete(binfo);
1134
1135                 ret = build_info_commit_dev(binfo);
1136                 if (ret)
1137                         return ret;
1138
1139                 ret = build_info_prepare(binfo, binfo->start + ofst,
1140                                          binfo->len - ofst);
1141                 if (ret)
1142                         return ret;
1143         }
1144
1145         v = readq(binfo->ioaddr + DFH);
1146         id = FIELD_GET(DFH_ID, v);
1147
1148         /* create platform device for dfl feature dev */
1149         ret = build_info_create_dev(binfo, dfh_id_to_type(id));
1150         if (ret)
1151                 return ret;
1152
1153         ret = create_feature_instance(binfo, 0, 0, 0);
1154         if (ret)
1155                 return ret;
1156         /*
1157          * find and parse FIU's child AFU via its NEXT_AFU register.
1158          * please note that only Port has valid NEXT_AFU pointer per spec.
1159          */
1160         v = readq(binfo->ioaddr + NEXT_AFU);
1161
1162         offset = FIELD_GET(NEXT_AFU_NEXT_DFH_OFST, v);
1163         if (offset)
1164                 return parse_feature_afu(binfo, offset);
1165
1166         dev_dbg(binfo->dev, "No AFUs detected on FIU %d\n", id);
1167
1168         return ret;
1169 }
1170
1171 static int parse_feature_private(struct build_feature_devs_info *binfo,
1172                                  resource_size_t ofst)
1173 {
1174         if (!is_feature_dev_detected(binfo)) {
1175                 dev_err(binfo->dev, "the private feature 0x%x does not belong to any AFU.\n",
1176                         feature_id(readq(binfo->ioaddr + ofst)));
1177                 return -EINVAL;
1178         }
1179
1180         return create_feature_instance(binfo, ofst, 0, 0);
1181 }
1182
1183 /**
1184  * parse_feature - parse a feature on given device feature list
1185  *
1186  * @binfo: build feature devices information.
1187  * @ofst: offset to current FIU header
1188  */
1189 static int parse_feature(struct build_feature_devs_info *binfo,
1190                          resource_size_t ofst)
1191 {
1192         u64 v;
1193         u32 type;
1194
1195         v = readq(binfo->ioaddr + ofst + DFH);
1196         type = FIELD_GET(DFH_TYPE, v);
1197
1198         switch (type) {
1199         case DFH_TYPE_AFU:
1200                 return parse_feature_afu(binfo, ofst);
1201         case DFH_TYPE_PRIVATE:
1202                 return parse_feature_private(binfo, ofst);
1203         case DFH_TYPE_FIU:
1204                 return parse_feature_fiu(binfo, ofst);
1205         default:
1206                 dev_info(binfo->dev,
1207                          "Feature Type %x is not supported.\n", type);
1208         }
1209
1210         return 0;
1211 }
1212
1213 static int parse_feature_list(struct build_feature_devs_info *binfo,
1214                               resource_size_t start, resource_size_t len)
1215 {
1216         resource_size_t end = start + len;
1217         int ret = 0;
1218         u32 ofst = 0;
1219         u64 v;
1220
1221         ret = build_info_prepare(binfo, start, len);
1222         if (ret)
1223                 return ret;
1224
1225         /* walk through the device feature list via DFH's next DFH pointer. */
1226         for (; start < end; start += ofst) {
1227                 if (end - start < DFH_SIZE) {
1228                         dev_err(binfo->dev, "The region is too small to contain a feature.\n");
1229                         return -EINVAL;
1230                 }
1231
1232                 ret = parse_feature(binfo, start - binfo->start);
1233                 if (ret)
1234                         return ret;
1235
1236                 v = readq(binfo->ioaddr + start - binfo->start + DFH);
1237                 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, v);
1238
1239                 /* stop parsing if EOL(End of List) is set or offset is 0 */
1240                 if ((v & DFH_EOL) || !ofst)
1241                         break;
1242         }
1243
1244         /* commit current feature device when reach the end of list */
1245         build_info_complete(binfo);
1246
1247         if (is_feature_dev_detected(binfo))
1248                 ret = build_info_commit_dev(binfo);
1249
1250         return ret;
1251 }
1252
1253 struct dfl_fpga_enum_info *dfl_fpga_enum_info_alloc(struct device *dev)
1254 {
1255         struct dfl_fpga_enum_info *info;
1256
1257         get_device(dev);
1258
1259         info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
1260         if (!info) {
1261                 put_device(dev);
1262                 return NULL;
1263         }
1264
1265         info->dev = dev;
1266         INIT_LIST_HEAD(&info->dfls);
1267
1268         return info;
1269 }
1270 EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_alloc);
1271
1272 void dfl_fpga_enum_info_free(struct dfl_fpga_enum_info *info)
1273 {
1274         struct dfl_fpga_enum_dfl *tmp, *dfl;
1275         struct device *dev;
1276
1277         if (!info)
1278                 return;
1279
1280         dev = info->dev;
1281
1282         /* remove all device feature lists in the list. */
1283         list_for_each_entry_safe(dfl, tmp, &info->dfls, node) {
1284                 list_del(&dfl->node);
1285                 devm_kfree(dev, dfl);
1286         }
1287
1288         /* remove irq table */
1289         if (info->irq_table)
1290                 devm_kfree(dev, info->irq_table);
1291
1292         devm_kfree(dev, info);
1293         put_device(dev);
1294 }
1295 EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_free);
1296
1297 /**
1298  * dfl_fpga_enum_info_add_dfl - add info of a device feature list to enum info
1299  *
1300  * @info: ptr to dfl_fpga_enum_info
1301  * @start: mmio resource address of the device feature list.
1302  * @len: mmio resource length of the device feature list.
1303  *
1304  * One FPGA device may have one or more Device Feature Lists (DFLs), use this
1305  * function to add information of each DFL to common data structure for next
1306  * step enumeration.
1307  *
1308  * Return: 0 on success, negative error code otherwise.
1309  */
1310 int dfl_fpga_enum_info_add_dfl(struct dfl_fpga_enum_info *info,
1311                                resource_size_t start, resource_size_t len)
1312 {
1313         struct dfl_fpga_enum_dfl *dfl;
1314
1315         dfl = devm_kzalloc(info->dev, sizeof(*dfl), GFP_KERNEL);
1316         if (!dfl)
1317                 return -ENOMEM;
1318
1319         dfl->start = start;
1320         dfl->len = len;
1321
1322         list_add_tail(&dfl->node, &info->dfls);
1323
1324         return 0;
1325 }
1326 EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_add_dfl);
1327
1328 /**
1329  * dfl_fpga_enum_info_add_irq - add irq table to enum info
1330  *
1331  * @info: ptr to dfl_fpga_enum_info
1332  * @nr_irqs: number of irqs of the DFL fpga device to be enumerated.
1333  * @irq_table: Linux IRQ numbers for all irqs, indexed by local irq index of
1334  *             this device.
1335  *
1336  * One FPGA device may have several interrupts. This function adds irq
1337  * information of the DFL fpga device to enum info for next step enumeration.
1338  * This function should be called before dfl_fpga_feature_devs_enumerate().
1339  * As we only support one irq domain for all DFLs in the same enum info, adding
1340  * irq table a second time for the same enum info will return error.
1341  *
1342  * If we need to enumerate DFLs which belong to different irq domains, we
1343  * should fill more enum info and enumerate them one by one.
1344  *
1345  * Return: 0 on success, negative error code otherwise.
1346  */
1347 int dfl_fpga_enum_info_add_irq(struct dfl_fpga_enum_info *info,
1348                                unsigned int nr_irqs, int *irq_table)
1349 {
1350         if (!nr_irqs || !irq_table)
1351                 return -EINVAL;
1352
1353         if (info->irq_table)
1354                 return -EEXIST;
1355
1356         info->irq_table = devm_kmemdup(info->dev, irq_table,
1357                                        sizeof(int) * nr_irqs, GFP_KERNEL);
1358         if (!info->irq_table)
1359                 return -ENOMEM;
1360
1361         info->nr_irqs = nr_irqs;
1362
1363         return 0;
1364 }
1365 EXPORT_SYMBOL_GPL(dfl_fpga_enum_info_add_irq);
1366
1367 static int remove_feature_dev(struct device *dev, void *data)
1368 {
1369         struct platform_device *pdev = to_platform_device(dev);
1370         enum dfl_id_type type = feature_dev_id_type(pdev);
1371         int id = pdev->id;
1372
1373         platform_device_unregister(pdev);
1374
1375         dfl_id_free(type, id);
1376
1377         return 0;
1378 }
1379
1380 static void remove_feature_devs(struct dfl_fpga_cdev *cdev)
1381 {
1382         device_for_each_child(&cdev->region->dev, NULL, remove_feature_dev);
1383 }
1384
1385 /**
1386  * dfl_fpga_feature_devs_enumerate - enumerate feature devices
1387  * @info: information for enumeration.
1388  *
1389  * This function creates a container device (base FPGA region), enumerates
1390  * feature devices based on the enumeration info and creates platform devices
1391  * under the container device.
1392  *
1393  * Return: dfl_fpga_cdev struct on success, -errno on failure
1394  */
1395 struct dfl_fpga_cdev *
1396 dfl_fpga_feature_devs_enumerate(struct dfl_fpga_enum_info *info)
1397 {
1398         struct build_feature_devs_info *binfo;
1399         struct dfl_fpga_enum_dfl *dfl;
1400         struct dfl_fpga_cdev *cdev;
1401         int ret = 0;
1402
1403         if (!info->dev)
1404                 return ERR_PTR(-ENODEV);
1405
1406         cdev = devm_kzalloc(info->dev, sizeof(*cdev), GFP_KERNEL);
1407         if (!cdev)
1408                 return ERR_PTR(-ENOMEM);
1409
1410         cdev->parent = info->dev;
1411         mutex_init(&cdev->lock);
1412         INIT_LIST_HEAD(&cdev->port_dev_list);
1413
1414         cdev->region = fpga_region_register(info->dev, NULL, NULL);
1415         if (IS_ERR(cdev->region)) {
1416                 ret = PTR_ERR(cdev->region);
1417                 goto free_cdev_exit;
1418         }
1419
1420         /* create and init build info for enumeration */
1421         binfo = devm_kzalloc(info->dev, sizeof(*binfo), GFP_KERNEL);
1422         if (!binfo) {
1423                 ret = -ENOMEM;
1424                 goto unregister_region_exit;
1425         }
1426
1427         binfo->dev = info->dev;
1428         binfo->cdev = cdev;
1429
1430         binfo->nr_irqs = info->nr_irqs;
1431         if (info->nr_irqs)
1432                 binfo->irq_table = info->irq_table;
1433
1434         /*
1435          * start enumeration for all feature devices based on Device Feature
1436          * Lists.
1437          */
1438         list_for_each_entry(dfl, &info->dfls, node) {
1439                 ret = parse_feature_list(binfo, dfl->start, dfl->len);
1440                 if (ret) {
1441                         remove_feature_devs(cdev);
1442                         build_info_free(binfo);
1443                         goto unregister_region_exit;
1444                 }
1445         }
1446
1447         build_info_free(binfo);
1448
1449         return cdev;
1450
1451 unregister_region_exit:
1452         fpga_region_unregister(cdev->region);
1453 free_cdev_exit:
1454         devm_kfree(info->dev, cdev);
1455         return ERR_PTR(ret);
1456 }
1457 EXPORT_SYMBOL_GPL(dfl_fpga_feature_devs_enumerate);
1458
1459 /**
1460  * dfl_fpga_feature_devs_remove - remove all feature devices
1461  * @cdev: fpga container device.
1462  *
1463  * Remove the container device and all feature devices under given container
1464  * devices.
1465  */
1466 void dfl_fpga_feature_devs_remove(struct dfl_fpga_cdev *cdev)
1467 {
1468         struct dfl_feature_platform_data *pdata, *ptmp;
1469
1470         mutex_lock(&cdev->lock);
1471         if (cdev->fme_dev)
1472                 put_device(cdev->fme_dev);
1473
1474         list_for_each_entry_safe(pdata, ptmp, &cdev->port_dev_list, node) {
1475                 struct platform_device *port_dev = pdata->dev;
1476
1477                 /* remove released ports */
1478                 if (!device_is_registered(&port_dev->dev)) {
1479                         dfl_id_free(feature_dev_id_type(port_dev),
1480                                     port_dev->id);
1481                         platform_device_put(port_dev);
1482                 }
1483
1484                 list_del(&pdata->node);
1485                 put_device(&port_dev->dev);
1486         }
1487         mutex_unlock(&cdev->lock);
1488
1489         remove_feature_devs(cdev);
1490
1491         fpga_region_unregister(cdev->region);
1492         devm_kfree(cdev->parent, cdev);
1493 }
1494 EXPORT_SYMBOL_GPL(dfl_fpga_feature_devs_remove);
1495
1496 /**
1497  * __dfl_fpga_cdev_find_port - find a port under given container device
1498  *
1499  * @cdev: container device
1500  * @data: data passed to match function
1501  * @match: match function used to find specific port from the port device list
1502  *
1503  * Find a port device under container device. This function needs to be
1504  * invoked with lock held.
1505  *
1506  * Return: pointer to port's platform device if successful, NULL otherwise.
1507  *
1508  * NOTE: you will need to drop the device reference with put_device() after use.
1509  */
1510 struct platform_device *
1511 __dfl_fpga_cdev_find_port(struct dfl_fpga_cdev *cdev, void *data,
1512                           int (*match)(struct platform_device *, void *))
1513 {
1514         struct dfl_feature_platform_data *pdata;
1515         struct platform_device *port_dev;
1516
1517         list_for_each_entry(pdata, &cdev->port_dev_list, node) {
1518                 port_dev = pdata->dev;
1519
1520                 if (match(port_dev, data) && get_device(&port_dev->dev))
1521                         return port_dev;
1522         }
1523
1524         return NULL;
1525 }
1526 EXPORT_SYMBOL_GPL(__dfl_fpga_cdev_find_port);
1527
1528 static int __init dfl_fpga_init(void)
1529 {
1530         int ret;
1531
1532         ret = bus_register(&dfl_bus_type);
1533         if (ret)
1534                 return ret;
1535
1536         dfl_ids_init();
1537
1538         ret = dfl_chardev_init();
1539         if (ret) {
1540                 dfl_ids_destroy();
1541                 bus_unregister(&dfl_bus_type);
1542         }
1543
1544         return ret;
1545 }
1546
1547 /**
1548  * dfl_fpga_cdev_release_port - release a port platform device
1549  *
1550  * @cdev: parent container device.
1551  * @port_id: id of the port platform device.
1552  *
1553  * This function allows user to release a port platform device. This is a
1554  * mandatory step before turn a port from PF into VF for SRIOV support.
1555  *
1556  * Return: 0 on success, negative error code otherwise.
1557  */
1558 int dfl_fpga_cdev_release_port(struct dfl_fpga_cdev *cdev, int port_id)
1559 {
1560         struct dfl_feature_platform_data *pdata;
1561         struct platform_device *port_pdev;
1562         int ret = -ENODEV;
1563
1564         mutex_lock(&cdev->lock);
1565         port_pdev = __dfl_fpga_cdev_find_port(cdev, &port_id,
1566                                               dfl_fpga_check_port_id);
1567         if (!port_pdev)
1568                 goto unlock_exit;
1569
1570         if (!device_is_registered(&port_pdev->dev)) {
1571                 ret = -EBUSY;
1572                 goto put_dev_exit;
1573         }
1574
1575         pdata = dev_get_platdata(&port_pdev->dev);
1576
1577         mutex_lock(&pdata->lock);
1578         ret = dfl_feature_dev_use_begin(pdata, true);
1579         mutex_unlock(&pdata->lock);
1580         if (ret)
1581                 goto put_dev_exit;
1582
1583         platform_device_del(port_pdev);
1584         cdev->released_port_num++;
1585 put_dev_exit:
1586         put_device(&port_pdev->dev);
1587 unlock_exit:
1588         mutex_unlock(&cdev->lock);
1589         return ret;
1590 }
1591 EXPORT_SYMBOL_GPL(dfl_fpga_cdev_release_port);
1592
1593 /**
1594  * dfl_fpga_cdev_assign_port - assign a port platform device back
1595  *
1596  * @cdev: parent container device.
1597  * @port_id: id of the port platform device.
1598  *
1599  * This function allows user to assign a port platform device back. This is
1600  * a mandatory step after disable SRIOV support.
1601  *
1602  * Return: 0 on success, negative error code otherwise.
1603  */
1604 int dfl_fpga_cdev_assign_port(struct dfl_fpga_cdev *cdev, int port_id)
1605 {
1606         struct dfl_feature_platform_data *pdata;
1607         struct platform_device *port_pdev;
1608         int ret = -ENODEV;
1609
1610         mutex_lock(&cdev->lock);
1611         port_pdev = __dfl_fpga_cdev_find_port(cdev, &port_id,
1612                                               dfl_fpga_check_port_id);
1613         if (!port_pdev)
1614                 goto unlock_exit;
1615
1616         if (device_is_registered(&port_pdev->dev)) {
1617                 ret = -EBUSY;
1618                 goto put_dev_exit;
1619         }
1620
1621         ret = platform_device_add(port_pdev);
1622         if (ret)
1623                 goto put_dev_exit;
1624
1625         pdata = dev_get_platdata(&port_pdev->dev);
1626
1627         mutex_lock(&pdata->lock);
1628         dfl_feature_dev_use_end(pdata);
1629         mutex_unlock(&pdata->lock);
1630
1631         cdev->released_port_num--;
1632 put_dev_exit:
1633         put_device(&port_pdev->dev);
1634 unlock_exit:
1635         mutex_unlock(&cdev->lock);
1636         return ret;
1637 }
1638 EXPORT_SYMBOL_GPL(dfl_fpga_cdev_assign_port);
1639
1640 static void config_port_access_mode(struct device *fme_dev, int port_id,
1641                                     bool is_vf)
1642 {
1643         void __iomem *base;
1644         u64 v;
1645
1646         base = dfl_get_feature_ioaddr_by_id(fme_dev, FME_FEATURE_ID_HEADER);
1647
1648         v = readq(base + FME_HDR_PORT_OFST(port_id));
1649
1650         v &= ~FME_PORT_OFST_ACC_CTRL;
1651         v |= FIELD_PREP(FME_PORT_OFST_ACC_CTRL,
1652                         is_vf ? FME_PORT_OFST_ACC_VF : FME_PORT_OFST_ACC_PF);
1653
1654         writeq(v, base + FME_HDR_PORT_OFST(port_id));
1655 }
1656
1657 #define config_port_vf_mode(dev, id) config_port_access_mode(dev, id, true)
1658 #define config_port_pf_mode(dev, id) config_port_access_mode(dev, id, false)
1659
1660 /**
1661  * dfl_fpga_cdev_config_ports_pf - configure ports to PF access mode
1662  *
1663  * @cdev: parent container device.
1664  *
1665  * This function is needed in sriov configuration routine. It could be used to
1666  * configure the all released ports from VF access mode to PF.
1667  */
1668 void dfl_fpga_cdev_config_ports_pf(struct dfl_fpga_cdev *cdev)
1669 {
1670         struct dfl_feature_platform_data *pdata;
1671
1672         mutex_lock(&cdev->lock);
1673         list_for_each_entry(pdata, &cdev->port_dev_list, node) {
1674                 if (device_is_registered(&pdata->dev->dev))
1675                         continue;
1676
1677                 config_port_pf_mode(cdev->fme_dev, pdata->id);
1678         }
1679         mutex_unlock(&cdev->lock);
1680 }
1681 EXPORT_SYMBOL_GPL(dfl_fpga_cdev_config_ports_pf);
1682
1683 /**
1684  * dfl_fpga_cdev_config_ports_vf - configure ports to VF access mode
1685  *
1686  * @cdev: parent container device.
1687  * @num_vfs: VF device number.
1688  *
1689  * This function is needed in sriov configuration routine. It could be used to
1690  * configure the released ports from PF access mode to VF.
1691  *
1692  * Return: 0 on success, negative error code otherwise.
1693  */
1694 int dfl_fpga_cdev_config_ports_vf(struct dfl_fpga_cdev *cdev, int num_vfs)
1695 {
1696         struct dfl_feature_platform_data *pdata;
1697         int ret = 0;
1698
1699         mutex_lock(&cdev->lock);
1700         /*
1701          * can't turn multiple ports into 1 VF device, only 1 port for 1 VF
1702          * device, so if released port number doesn't match VF device number,
1703          * then reject the request with -EINVAL error code.
1704          */
1705         if (cdev->released_port_num != num_vfs) {
1706                 ret = -EINVAL;
1707                 goto done;
1708         }
1709
1710         list_for_each_entry(pdata, &cdev->port_dev_list, node) {
1711                 if (device_is_registered(&pdata->dev->dev))
1712                         continue;
1713
1714                 config_port_vf_mode(cdev->fme_dev, pdata->id);
1715         }
1716 done:
1717         mutex_unlock(&cdev->lock);
1718         return ret;
1719 }
1720 EXPORT_SYMBOL_GPL(dfl_fpga_cdev_config_ports_vf);
1721
1722 static irqreturn_t dfl_irq_handler(int irq, void *arg)
1723 {
1724         struct eventfd_ctx *trigger = arg;
1725
1726         eventfd_signal(trigger, 1);
1727         return IRQ_HANDLED;
1728 }
1729
1730 static int do_set_irq_trigger(struct dfl_feature *feature, unsigned int idx,
1731                               int fd)
1732 {
1733         struct platform_device *pdev = feature->dev;
1734         struct eventfd_ctx *trigger;
1735         int irq, ret;
1736
1737         irq = feature->irq_ctx[idx].irq;
1738
1739         if (feature->irq_ctx[idx].trigger) {
1740                 free_irq(irq, feature->irq_ctx[idx].trigger);
1741                 kfree(feature->irq_ctx[idx].name);
1742                 eventfd_ctx_put(feature->irq_ctx[idx].trigger);
1743                 feature->irq_ctx[idx].trigger = NULL;
1744         }
1745
1746         if (fd < 0)
1747                 return 0;
1748
1749         feature->irq_ctx[idx].name =
1750                 kasprintf(GFP_KERNEL, "fpga-irq[%u](%s-%x)", idx,
1751                           dev_name(&pdev->dev), feature->id);
1752         if (!feature->irq_ctx[idx].name)
1753                 return -ENOMEM;
1754
1755         trigger = eventfd_ctx_fdget(fd);
1756         if (IS_ERR(trigger)) {
1757                 ret = PTR_ERR(trigger);
1758                 goto free_name;
1759         }
1760
1761         ret = request_irq(irq, dfl_irq_handler, 0,
1762                           feature->irq_ctx[idx].name, trigger);
1763         if (!ret) {
1764                 feature->irq_ctx[idx].trigger = trigger;
1765                 return ret;
1766         }
1767
1768         eventfd_ctx_put(trigger);
1769 free_name:
1770         kfree(feature->irq_ctx[idx].name);
1771
1772         return ret;
1773 }
1774
1775 /**
1776  * dfl_fpga_set_irq_triggers - set eventfd triggers for dfl feature interrupts
1777  *
1778  * @feature: dfl sub feature.
1779  * @start: start of irq index in this dfl sub feature.
1780  * @count: number of irqs.
1781  * @fds: eventfds to bind with irqs. unbind related irq if fds[n] is negative.
1782  *       unbind "count" specified number of irqs if fds ptr is NULL.
1783  *
1784  * Bind given eventfds with irqs in this dfl sub feature. Unbind related irq if
1785  * fds[n] is negative. Unbind "count" specified number of irqs if fds ptr is
1786  * NULL.
1787  *
1788  * Return: 0 on success, negative error code otherwise.
1789  */
1790 int dfl_fpga_set_irq_triggers(struct dfl_feature *feature, unsigned int start,
1791                               unsigned int count, int32_t *fds)
1792 {
1793         unsigned int i;
1794         int ret = 0;
1795
1796         /* overflow */
1797         if (unlikely(start + count < start))
1798                 return -EINVAL;
1799
1800         /* exceeds nr_irqs */
1801         if (start + count > feature->nr_irqs)
1802                 return -EINVAL;
1803
1804         for (i = 0; i < count; i++) {
1805                 int fd = fds ? fds[i] : -1;
1806
1807                 ret = do_set_irq_trigger(feature, start + i, fd);
1808                 if (ret) {
1809                         while (i--)
1810                                 do_set_irq_trigger(feature, start + i, -1);
1811                         break;
1812                 }
1813         }
1814
1815         return ret;
1816 }
1817 EXPORT_SYMBOL_GPL(dfl_fpga_set_irq_triggers);
1818
1819 /**
1820  * dfl_feature_ioctl_get_num_irqs - dfl feature _GET_IRQ_NUM ioctl interface.
1821  * @pdev: the feature device which has the sub feature
1822  * @feature: the dfl sub feature
1823  * @arg: ioctl argument
1824  *
1825  * Return: 0 on success, negative error code otherwise.
1826  */
1827 long dfl_feature_ioctl_get_num_irqs(struct platform_device *pdev,
1828                                     struct dfl_feature *feature,
1829                                     unsigned long arg)
1830 {
1831         return put_user(feature->nr_irqs, (__u32 __user *)arg);
1832 }
1833 EXPORT_SYMBOL_GPL(dfl_feature_ioctl_get_num_irqs);
1834
1835 /**
1836  * dfl_feature_ioctl_set_irq - dfl feature _SET_IRQ ioctl interface.
1837  * @pdev: the feature device which has the sub feature
1838  * @feature: the dfl sub feature
1839  * @arg: ioctl argument
1840  *
1841  * Return: 0 on success, negative error code otherwise.
1842  */
1843 long dfl_feature_ioctl_set_irq(struct platform_device *pdev,
1844                                struct dfl_feature *feature,
1845                                unsigned long arg)
1846 {
1847         struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev);
1848         struct dfl_fpga_irq_set hdr;
1849         s32 *fds;
1850         long ret;
1851
1852         if (!feature->nr_irqs)
1853                 return -ENOENT;
1854
1855         if (copy_from_user(&hdr, (void __user *)arg, sizeof(hdr)))
1856                 return -EFAULT;
1857
1858         if (!hdr.count || (hdr.start + hdr.count > feature->nr_irqs) ||
1859             (hdr.start + hdr.count < hdr.start))
1860                 return -EINVAL;
1861
1862         fds = memdup_user((void __user *)(arg + sizeof(hdr)),
1863                           hdr.count * sizeof(s32));
1864         if (IS_ERR(fds))
1865                 return PTR_ERR(fds);
1866
1867         mutex_lock(&pdata->lock);
1868         ret = dfl_fpga_set_irq_triggers(feature, hdr.start, hdr.count, fds);
1869         mutex_unlock(&pdata->lock);
1870
1871         kfree(fds);
1872         return ret;
1873 }
1874 EXPORT_SYMBOL_GPL(dfl_feature_ioctl_set_irq);
1875
1876 static void __exit dfl_fpga_exit(void)
1877 {
1878         dfl_chardev_uinit();
1879         dfl_ids_destroy();
1880         bus_unregister(&dfl_bus_type);
1881 }
1882
1883 module_init(dfl_fpga_init);
1884 module_exit(dfl_fpga_exit);
1885
1886 MODULE_DESCRIPTION("FPGA Device Feature List (DFL) Support");
1887 MODULE_AUTHOR("Intel Corporation");
1888 MODULE_LICENSE("GPL v2");