boot/bootdev-uclass.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright 2021 Google LLC
   4  * Written by Simon Glass <sjg@chromium.org>
   5  */
   6
   7 #define LOG_CATEGORY UCLASS_BOOTSTD
   8
   9 #include <common.h>
  10 #include <dm.h>
  11 #include <bootdev.h>
  12 #include <bootflow.h>
  13 #include <bootmeth.h>
  14 #include <bootstd.h>
  15 #include <fs.h>
  16 #include <log.h>
  17 #include <malloc.h>
  18 #include <part.h>
  19 #include <sort.h>
  20 #include <dm/device-internal.h>
  21 #include <dm/lists.h>
  22 #include <dm/uclass-internal.h>
  23
  24 enum {
  25         /*
  26          * Set some sort of limit on the number of partitions a bootdev can
  27          * have. Note that for disks this limits the partitions numbers that
  28          * are scanned to 1..MAX_BOOTFLOWS_PER_BOOTDEV
  29          */
  30         MAX_PART_PER_BOOTDEV    = 30,
  31
  32         /* Maximum supported length of the "boot_targets" env string */
  33         BOOT_TARGETS_MAX_LEN    = 100,
  34 };
  35
  36 int bootdev_add_bootflow(struct bootflow *bflow)
  37 {
  38         struct bootstd_priv *std;
  39         struct bootflow *new;
  40         int ret;
  41
  42         assert(bflow->dev);
  43         ret = bootstd_get_priv(&std);
  44         if (ret)
  45                 return ret;
  46
  47         new = malloc(sizeof(*bflow));
  48         if (!new)
  49                 return log_msg_ret("bflow", -ENOMEM);
  50         memcpy(new, bflow, sizeof(*bflow));
  51
  52         list_add_tail(&new->glob_node, &std->glob_head);
  53         if (bflow->dev) {
  54                 struct bootdev_uc_plat *ucp = dev_get_uclass_plat(bflow->dev);
  55
  56                 list_add_tail(&new->bm_node, &ucp->bootflow_head);
  57         }
  58
  59         return 0;
  60 }
  61
  62 int bootdev_first_bootflow(struct udevice *dev, struct bootflow **bflowp)
  63 {
  64         struct bootdev_uc_plat *ucp = dev_get_uclass_plat(dev);
  65
  66         if (list_empty(&ucp->bootflow_head))
  67                 return -ENOENT;
  68
  69         *bflowp = list_first_entry(&ucp->bootflow_head, struct bootflow,
  70                                    bm_node);
  71
  72         return 0;
  73 }
  74
  75 int bootdev_next_bootflow(struct bootflow **bflowp)
  76 {
  77         struct bootflow *bflow = *bflowp;
  78         struct bootdev_uc_plat *ucp = dev_get_uclass_plat(bflow->dev);
  79
  80         *bflowp = NULL;
  81
  82         if (list_is_last(&bflow->bm_node, &ucp->bootflow_head))
  83                 return -ENOENT;
  84
  85         *bflowp = list_entry(bflow->bm_node.next, struct bootflow, bm_node);
  86
  87         return 0;
  88 }
  89
  90 int bootdev_bind(struct udevice *parent, const char *drv_name, const char *name,
  91                  struct udevice **devp)
  92 {
  93         struct udevice *dev;
  94         char dev_name[30];
  95         char *str;
  96         int ret;
  97
  98         snprintf(dev_name, sizeof(dev_name), "%s.%s", parent->name, name);
  99         str = strdup(dev_name);
 100         if (!str)
 101                 return -ENOMEM;
 102         ret = device_bind_driver(parent, drv_name, str, &dev);
 103         if (ret)
 104                 return ret;
 105         device_set_name_alloced(dev);
 106         *devp = dev;
 107
 108         return 0;
 109 }
 110
 111 int bootdev_find_in_blk(struct udevice *dev, struct udevice *blk,
 112                         struct bootflow_iter *iter, struct bootflow *bflow)
 113 {
 114         struct bootmeth_uc_plat *plat = dev_get_uclass_plat(bflow->method);
 115         bool allow_any_part = plat->flags & BOOTMETHF_ANY_PART;
 116         struct blk_desc *desc = dev_get_uclass_plat(blk);
 117         struct disk_partition info;
 118         char partstr[20];
 119         char name[60];
 120         int ret;
 121
 122         /* Sanity check */
 123         if (iter->part >= MAX_PART_PER_BOOTDEV)
 124                 return log_msg_ret("max", -ESHUTDOWN);
 125
 126         bflow->blk = blk;
 127         if (iter->part)
 128                 snprintf(partstr, sizeof(partstr), "part_%x", iter->part);
 129         else
 130                 strcpy(partstr, "whole");
 131         snprintf(name, sizeof(name), "%s.%s", dev->name, partstr);
 132         bflow->name = strdup(name);
 133         if (!bflow->name)
 134                 return log_msg_ret("name", -ENOMEM);
 135
 136         bflow->part = iter->part;
 137
 138         ret = bootmeth_check(bflow->method, iter);
 139         if (ret)
 140                 return log_msg_ret("check", ret);
 141
 142         /*
 143          * partition numbers start at 0 so this cannot succeed, but it can tell
 144          * us whether there is valid media there
 145          */
 146         ret = part_get_info(desc, iter->part, &info);
 147         log_debug("part_get_info() returned %d\n", ret);
 148         if (!iter->part && ret == -ENOENT)
 149                 ret = 0;
 150
 151         /*
 152          * This error indicates the media is not present. Otherwise we just
 153          * blindly scan the next partition. We could be more intelligent here
 154          * and check which partition numbers actually exist.
 155          */
 156         if (ret == -EOPNOTSUPP)
 157                 ret = -ESHUTDOWN;
 158         else
 159                 bflow->state = BOOTFLOWST_MEDIA;
 160         if (ret && !allow_any_part) {
 161                 /* allow partition 1 to be missing */
 162                 if (iter->part == 1) {
 163                         iter->max_part = 3;
 164                         ret = -ENOENT;
 165                 }
 166
 167                 return log_msg_ret("part", ret);
 168         }
 169
 170         /*
 171          * Currently we don't get the number of partitions, so just
 172          * assume a large number
 173          */
 174         iter->max_part = MAX_PART_PER_BOOTDEV;
 175
 176         /* If this is the whole disk, check if we have bootable partitions */
 177         if (!iter->part) {
 178                 iter->first_bootable = part_get_bootable(desc);
 179                 log_debug("checking bootable=%d\n", iter->first_bootable);
 180         } else if (allow_any_part) {
 181                 /*
 182                  * allow any partition to be scanned, by skipping any checks
 183                  * for filesystems or partition contents on this disk
 184                  */
 185
 186         /* if there are bootable partitions, scan only those */
 187         } else if (iter->first_bootable >= 0 &&
 188                    (iter->first_bootable ? !info.bootable : iter->part != 1)) {
 189                 return log_msg_ret("boot", -EINVAL);
 190         } else {
 191                 ret = fs_set_blk_dev_with_part(desc, bflow->part);
 192                 bflow->state = BOOTFLOWST_PART;
 193                 if (ret)
 194                         return log_msg_ret("fs", ret);
 195
 196                 log_debug("%s: Found partition %x type %x fstype %d\n",
 197                           blk->name, bflow->part,
 198                           IS_ENABLED(CONFIG_DOS_PARTITION) ?
 199                           disk_partition_sys_ind(&info) : 0,
 200                           ret ? -1 : fs_get_type());
 201                 bflow->blk = blk;
 202                 bflow->state = BOOTFLOWST_FS;
 203         }
 204
 205         log_debug("method %s\n", bflow->method->name);
 206         ret = bootmeth_read_bootflow(bflow->method, bflow);
 207         if (ret)
 208                 return log_msg_ret("method", ret);
 209
 210         return 0;
 211 }
 212
 213 void bootdev_list(bool probe)
 214 {
 215         struct udevice *dev;
 216         int ret;
 217         int i;
 218
 219         printf("Seq  Probed  Status  Uclass    Name\n");
 220         printf("---  ------  ------  --------  ------------------\n");
 221         if (probe)
 222                 ret = uclass_first_device_check(UCLASS_BOOTDEV, &dev);
 223         else
 224                 ret = uclass_find_first_device(UCLASS_BOOTDEV, &dev);
 225         for (i = 0; dev; i++) {
 226                 printf("%3x   [ %c ]  %6s  %-9.9s %s\n", dev_seq(dev),
 227                        device_active(dev) ? '+' : ' ',
 228                        ret ? simple_itoa(-ret) : "OK",
 229                        dev_get_uclass_name(dev_get_parent(dev)), dev->name);
 230                 if (probe)
 231                         ret = uclass_next_device_check(&dev);
 232                 else
 233                         ret = uclass_find_next_device(&dev);
 234         }
 235         printf("---  ------  ------  --------  ------------------\n");
 236         printf("(%d bootdev%s)\n", i, i != 1 ? "s" : "");
 237 }
 238
 239 int bootdev_setup_for_dev(struct udevice *parent, const char *drv_name)
 240 {
 241         struct udevice *bdev;
 242         int ret;
 243
 244         ret = device_find_first_child_by_uclass(parent, UCLASS_BOOTDEV,
 245                                                 &bdev);
 246         if (ret) {
 247                 if (ret != -ENODEV) {
 248                         log_debug("Cannot access bootdev device\n");
 249                         return ret;
 250                 }
 251
 252                 ret = bootdev_bind(parent, drv_name, "bootdev", &bdev);
 253                 if (ret) {
 254                         log_debug("Cannot create bootdev device\n");
 255                         return ret;
 256                 }
 257         }
 258
 259         return 0;
 260 }
 261
 262 static int bootdev_get_suffix_start(struct udevice *dev, const char *suffix)
 263 {
 264         int len, slen;
 265
 266         len = strlen(dev->name);
 267         slen = strlen(suffix);
 268         if (len > slen && !strcmp(suffix, dev->name + len - slen))
 269                 return len - slen;
 270
 271         return len;
 272 }
 273
 274 int bootdev_setup_for_sibling_blk(struct udevice *blk, const char *drv_name)
 275 {
 276         struct udevice *parent, *dev;
 277         char dev_name[50];
 278         int ret, len;
 279
 280         len = bootdev_get_suffix_start(blk, ".blk");
 281         snprintf(dev_name, sizeof(dev_name), "%.*s.%s", len, blk->name,
 282                  "bootdev");
 283
 284         parent = dev_get_parent(blk);
 285         ret = device_find_child_by_name(parent, dev_name, &dev);
 286         if (ret) {
 287                 char *str;
 288
 289                 if (ret != -ENODEV) {
 290                         log_debug("Cannot access bootdev device\n");
 291                         return ret;
 292                 }
 293                 str = strdup(dev_name);
 294                 if (!str)
 295                         return -ENOMEM;
 296
 297                 ret = device_bind_driver(parent, drv_name, str, &dev);
 298                 if (ret) {
 299                         log_debug("Cannot create bootdev device\n");
 300                         return ret;
 301                 }
 302                 device_set_name_alloced(dev);
 303         }
 304
 305         return 0;
 306 }
 307
 308 int bootdev_get_sibling_blk(struct udevice *dev, struct udevice **blkp)
 309 {
 310         struct udevice *parent = dev_get_parent(dev);
 311         struct udevice *blk;
 312         int ret, len;
 313
 314         if (device_get_uclass_id(dev) != UCLASS_BOOTDEV)
 315                 return -EINVAL;
 316
 317         /*
 318          * This should always work if bootdev_setup_for_sibling_blk() was used
 319          */
 320         len = bootdev_get_suffix_start(dev, ".bootdev");
 321         ret = device_find_child_by_namelen(parent, dev->name, len, &blk);
 322         if (ret) {
 323                 char dev_name[50];
 324
 325                 snprintf(dev_name, sizeof(dev_name), "%.*s.blk", len,
 326                          dev->name);
 327                 ret = device_find_child_by_name(parent, dev_name, &blk);
 328                 if (ret)
 329                         return log_msg_ret("find", ret);
 330         }
 331         ret = device_probe(blk);
 332         if (ret)
 333                 return log_msg_ret("act", ret);
 334         *blkp = blk;
 335
 336         return 0;
 337 }
 338
 339 static int bootdev_get_from_blk(struct udevice *blk, struct udevice **bootdevp)
 340 {
 341         struct udevice *parent = dev_get_parent(blk);
 342         struct udevice *bootdev;
 343         char dev_name[50];
 344         int ret, len;
 345
 346         if (device_get_uclass_id(blk) != UCLASS_BLK)
 347                 return -EINVAL;
 348
 349         /* This should always work if bootdev_setup_for_sibling_blk() was used */
 350         len = bootdev_get_suffix_start(blk, ".blk");
 351         snprintf(dev_name, sizeof(dev_name), "%.*s.%s", len, blk->name,
 352                  "bootdev");
 353         ret = device_find_child_by_name(parent, dev_name, &bootdev);
 354         if (ret)
 355                 return log_msg_ret("find", ret);
 356         *bootdevp = bootdev;
 357
 358         return 0;
 359 }
 360
 361 int bootdev_unbind_dev(struct udevice *parent)
 362 {
 363         struct udevice *dev;
 364         int ret;
 365
 366         ret = device_find_first_child_by_uclass(parent, UCLASS_BOOTDEV, &dev);
 367         if (!ret) {
 368                 ret = device_remove(dev, DM_REMOVE_NORMAL);
 369                 if (ret)
 370                         return log_msg_ret("rem", ret);
 371                 ret = device_unbind(dev);
 372                 if (ret)
 373                         return log_msg_ret("unb", ret);
 374         }
 375
 376         return 0;
 377 }
 378
 379 /**
 380  * label_to_uclass() - Convert a label to a uclass and sequence number
 381  *
 382  * @label: Label to look up (e.g. "mmc1" or "mmc0")
 383  * @seqp: Returns the sequence number, or -1 if none
 384  * @method_flagsp: If non-NULL, returns any flags implied by the label
 385  * (enum bootflow_meth_flags_t), 0 if none
 386  * Returns: sequence number on success, -EPFNOSUPPORT is the uclass is not
 387  * known, other -ve error code on other error
 388  */
 389 static int label_to_uclass(const char *label, int *seqp, int *method_flagsp)
 390 {
 391         int seq, len, method_flags;
 392         enum uclass_id id;
 393         const char *end;
 394
 395         method_flags = 0;
 396         seq = trailing_strtoln_end(label, NULL, &end);
 397         len = end - label;
 398         if (!len)
 399                 return -EINVAL;
 400         id = uclass_get_by_namelen(label, len);
 401         log_debug("find %s: seq=%d, id=%d/%s\n", label, seq, id,
 402                   uclass_get_name(id));
 403         if (id == UCLASS_INVALID) {
 404                 /* try some special cases */
 405                 if (IS_ENABLED(CONFIG_BOOTDEV_SPI_FLASH) &&
 406                     !strncmp("spi", label, len)) {
 407                         id = UCLASS_SPI_FLASH;
 408                 } else if (IS_ENABLED(CONFIG_BOOTDEV_ETH) &&
 409                     !strncmp("pxe", label, len)) {
 410                         id = UCLASS_ETH;
 411                         method_flags |= BOOTFLOW_METHF_PXE_ONLY;
 412                 } else if (IS_ENABLED(CONFIG_BOOTDEV_ETH) &&
 413                     !strncmp("dhcp", label, len)) {
 414                         id = UCLASS_ETH;
 415                         method_flags |= BOOTFLOW_METHF_DHCP_ONLY;
 416                 } else {
 417                         return -EPFNOSUPPORT;
 418                 }
 419         }
 420         if (id == UCLASS_USB)
 421                 id = UCLASS_MASS_STORAGE;
 422         *seqp = seq;
 423         if (method_flagsp)
 424                 *method_flagsp = method_flags;
 425
 426         return id;
 427 }
 428
 429 int bootdev_find_by_label(const char *label, struct udevice **devp,
 430                           int *method_flagsp)
 431 {
 432         int seq, ret, method_flags = 0;
 433         struct udevice *media;
 434         struct uclass *uc;
 435         enum uclass_id id;
 436
 437         ret = label_to_uclass(label, &seq, &method_flags);
 438         if (ret < 0)
 439                 return log_msg_ret("uc", ret);
 440         id = ret;
 441
 442         /* Iterate through devices in the media uclass (e.g. UCLASS_MMC) */
 443         uclass_id_foreach_dev(id, media, uc) {
 444                 struct udevice *bdev, *blk;
 445                 int ret;
 446
 447                 /* if there is no seq, match anything */
 448                 if (seq != -1 && dev_seq(media) != seq) {
 449                         log_debug("- skip, media seq=%d\n", dev_seq(media));
 450                         continue;
 451                 }
 452
 453                 ret = device_find_first_child_by_uclass(media, UCLASS_BOOTDEV,
 454                                                         &bdev);
 455                 if (ret) {
 456                         log_debug("- looking via blk, seq=%d, id=%d\n", seq,
 457                                   id);
 458                         ret = blk_find_device(id, seq, &blk);
 459                         if (!ret) {
 460                                 log_debug("- get from blk %s\n", blk->name);
 461                                 ret = bootdev_get_from_blk(blk, &bdev);
 462                         }
 463                 }
 464                 if (!ret) {
 465                         log_debug("- found %s\n", bdev->name);
 466                         *devp = bdev;
 467
 468                         /*
 469                          * if no sequence number was provided, we must scan all
 470                          * bootdevs for this media uclass
 471                          */
 472                         if (seq == -1)
 473                                 method_flags |= BOOTFLOW_METHF_SINGLE_UCLASS;
 474                         if (method_flagsp)
 475                                 *method_flagsp = method_flags;
 476                         log_debug("method flags %x\n", method_flags);
 477                         return 0;
 478                 }
 479                 log_debug("- no device in %s\n", media->name);
 480         }
 481
 482         return -ENOENT;
 483 }
 484
 485 int bootdev_find_by_any(const char *name, struct udevice **devp,
 486                         int *method_flagsp)
 487 {
 488         struct udevice *dev;
 489         int method_flags = 0;
 490         int ret = -ENODEV, seq;
 491         char *endp;
 492
 493         seq = simple_strtol(name, &endp, 16);
 494
 495         /* Select by name, label or number */
 496         if (*endp) {
 497                 ret = uclass_get_device_by_name(UCLASS_BOOTDEV, name, &dev);
 498                 if (ret == -ENODEV) {
 499                         ret = bootdev_find_by_label(name, &dev, &method_flags);
 500                         if (ret) {
 501                                 printf("Cannot find bootdev '%s' (err=%d)\n",
 502                                        name, ret);
 503                                 return log_msg_ret("lab", ret);
 504                         }
 505                         ret = device_probe(dev);
 506                 }
 507                 if (ret) {
 508                         printf("Cannot probe bootdev '%s' (err=%d)\n", name,
 509                                ret);
 510                         return log_msg_ret("pro", ret);
 511                 }
 512         } else if (IS_ENABLED(CONFIG_BOOTSTD_FULL)) {
 513                 ret = uclass_get_device_by_seq(UCLASS_BOOTDEV, seq, &dev);
 514                 method_flags |= BOOTFLOW_METHF_SINGLE_DEV;
 515         }
 516         if (ret) {
 517                 printf("Cannot find '%s' (err=%d)\n", name, ret);
 518                 return ret;
 519         }
 520
 521         *devp = dev;
 522         if (method_flagsp)
 523                 *method_flagsp = method_flags;
 524
 525         return 0;
 526 }
 527
 528 int bootdev_hunt_and_find_by_label(const char *label, struct udevice **devp,
 529                                    int *method_flagsp)
 530 {
 531         int ret;
 532
 533         ret = bootdev_hunt(label, false);
 534         if (ret)
 535                 return log_msg_ret("scn", ret);
 536         ret = bootdev_find_by_label(label, devp, method_flagsp);
 537         if (ret)
 538                 return log_msg_ret("fnd", ret);
 539
 540         return 0;
 541 }
 542
 543 static int default_get_bootflow(struct udevice *dev, struct bootflow_iter *iter,
 544                                 struct bootflow *bflow)
 545 {
 546         struct udevice *blk;
 547         int ret;
 548
 549         ret = bootdev_get_sibling_blk(dev, &blk);
 550         log_debug("sibling_blk ret=%d, blk=%s\n", ret,
 551                   ret ? "(none)" : blk->name);
 552         /*
 553          * If there is no media, indicate that no more partitions should be
 554          * checked
 555          */
 556         if (ret == -EOPNOTSUPP)
 557                 ret = -ESHUTDOWN;
 558         if (ret)
 559                 return log_msg_ret("blk", ret);
 560         assert(blk);
 561         ret = bootdev_find_in_blk(dev, blk, iter, bflow);
 562         if (ret)
 563                 return log_msg_ret("find", ret);
 564
 565         return 0;
 566 }
 567
 568 int bootdev_get_bootflow(struct udevice *dev, struct bootflow_iter *iter,
 569                          struct bootflow *bflow)
 570 {
 571         const struct bootdev_ops *ops = bootdev_get_ops(dev);
 572
 573         log_debug("->get_bootflow %s,%x=%p\n", dev->name, iter->part,
 574                   ops->get_bootflow);
 575         bootflow_init(bflow, dev, iter->method);
 576         if (!ops->get_bootflow)
 577                 return default_get_bootflow(dev, iter, bflow);
 578
 579         return ops->get_bootflow(dev, iter, bflow);
 580 }
 581
 582 void bootdev_clear_bootflows(struct udevice *dev)
 583 {
 584         struct bootdev_uc_plat *ucp = dev_get_uclass_plat(dev);
 585
 586         while (!list_empty(&ucp->bootflow_head)) {
 587                 struct bootflow *bflow;
 588
 589                 bflow = list_first_entry(&ucp->bootflow_head, struct bootflow,
 590                                          bm_node);
 591                 bootflow_remove(bflow);
 592         }
 593 }
 594
 595 int bootdev_next_label(struct bootflow_iter *iter, struct udevice **devp,
 596                        int *method_flagsp)
 597 {
 598         struct udevice *dev;
 599
 600         log_debug("next\n");
 601         for (dev = NULL; !dev && iter->labels[++iter->cur_label];) {
 602                 const char *label = iter->labels[iter->cur_label];
 603                 int ret;
 604
 605                 log_debug("Scanning: %s\n", label);
 606                 ret = bootdev_hunt_and_find_by_label(label, &dev,
 607                                                      method_flagsp);
 608                 if (iter->flags & BOOTFLOWIF_SHOW) {
 609                         if (ret == -EPFNOSUPPORT) {
 610                                 log_warning("Unknown uclass '%s' in label\n",
 611                                             label);
 612                         } else if (ret == -ENOENT) {
 613                                 /*
 614                                  * looking for, e.g. 'scsi0' should find
 615                                  * something if SCSI is present
 616                                  */
 617                                 if (!trailing_strtol(label)) {
 618                                         log_warning("No bootdevs for '%s'\n",
 619                                                     label);
 620                                 }
 621                         }
 622                 }
 623
 624         }
 625
 626         if (!dev)
 627                 return log_msg_ret("fin", -ENODEV);
 628         *devp = dev;
 629
 630         return 0;
 631 }
 632
 633 int bootdev_next_prio(struct bootflow_iter *iter, struct udevice **devp)
 634 {
 635         struct udevice *dev = *devp, *last_dev = NULL;
 636         bool found;
 637         int ret;
 638
 639         /* find the next device with this priority */
 640         *devp = NULL;
 641         log_debug("next prio %d: dev=%p/%s\n", iter->cur_prio, dev,
 642                   dev ? dev->name : "none");
 643         do {
 644                 /*
 645                  * Don't probe devices here since they may not be of the
 646                  * required priority
 647                  */
 648                 if (!dev)
 649                         uclass_find_first_device(UCLASS_BOOTDEV, &dev);
 650                 else
 651                         uclass_find_next_device(&dev);
 652                 found = false;
 653
 654                 /* scan for the next device with the correct priority */
 655                 while (dev) {
 656                         struct bootdev_uc_plat *plat;
 657
 658                         plat = dev_get_uclass_plat(dev);
 659                         log_debug("- %s: %d, want %d\n", dev->name, plat->prio,
 660                                   iter->cur_prio);
 661                         if (plat->prio == iter->cur_prio)
 662                                 break;
 663                         uclass_find_next_device(&dev);
 664                 }
 665
 666                 /* none found for this priority, so move to the next */
 667                 if (!dev) {
 668                         log_debug("None found at prio %d, moving to %d\n",
 669                                   iter->cur_prio, iter->cur_prio + 1);
 670                         if (++iter->cur_prio == BOOTDEVP_COUNT)
 671                                 return log_msg_ret("fin", -ENODEV);
 672
 673                         if (iter->flags & BOOTFLOWIF_HUNT) {
 674                                 /* hunt to find new bootdevs */
 675                                 ret = bootdev_hunt_prio(iter->cur_prio,
 676                                                         iter->flags &
 677                                                         BOOTFLOWIF_SHOW);
 678                                 log_debug("- bootdev_hunt_prio() ret %d\n",
 679                                           ret);
 680                                 if (ret)
 681                                         return log_msg_ret("hun", ret);
 682                         }
 683                 } else {
 684                         ret = device_probe(dev);
 685                         if (!ret)
 686                                 last_dev = dev;
 687                         if (ret) {
 688                                 log_warning("Device '%s' failed to probe\n",
 689                                           dev->name);
 690                                 if (last_dev == dev) {
 691                                         /*
 692                                          * We have already tried this device
 693                                          * and it failed to probe. Give up.
 694                                          */
 695                                         return log_msg_ret("probe", ret);
 696                                 }
 697                                 last_dev = dev;
 698                                 dev = NULL;
 699                         }
 700                 }
 701         } while (!dev);
 702
 703         *devp = dev;
 704
 705         return 0;
 706 }
 707
 708 int bootdev_setup_iter(struct bootflow_iter *iter, const char *label,
 709                        struct udevice **devp, int *method_flagsp)
 710 {
 711         struct udevice *bootstd, *dev = NULL;
 712         bool show = iter->flags & BOOTFLOWIF_SHOW;
 713         int method_flags;
 714         int ret;
 715
 716         ret = uclass_first_device_err(UCLASS_BOOTSTD, &bootstd);
 717         if (ret) {
 718                 log_err("Missing bootstd device\n");
 719                 return log_msg_ret("std", ret);
 720         }
 721
 722         /* hunt for any pre-scan devices */
 723         if (iter->flags & BOOTFLOWIF_HUNT) {
 724                 ret = bootdev_hunt_prio(BOOTDEVP_1_PRE_SCAN, show);
 725                 log_debug("- bootdev_hunt_prio() ret %d\n", ret);
 726                 if (ret)
 727                         return log_msg_ret("pre", ret);
 728         }
 729
 730         /* Handle scanning a single device */
 731         if (IS_ENABLED(CONFIG_BOOTSTD_FULL) && label) {
 732                 if (iter->flags & BOOTFLOWIF_HUNT) {
 733                         ret = bootdev_hunt(label, show);
 734                         if (ret)
 735                                 return log_msg_ret("hun", ret);
 736                 }
 737                 ret = bootdev_find_by_any(label, &dev, &method_flags);
 738                 if (ret)
 739                         return log_msg_ret("lab", ret);
 740
 741                 log_debug("method_flags: %x\n", method_flags);
 742                 if (method_flags & BOOTFLOW_METHF_SINGLE_UCLASS)
 743                         iter->flags |= BOOTFLOWIF_SINGLE_UCLASS;
 744                 else if (method_flags & BOOTFLOW_METHF_SINGLE_DEV)
 745                         iter->flags |= BOOTFLOWIF_SINGLE_DEV;
 746                 else
 747                         iter->flags |= BOOTFLOWIF_SINGLE_MEDIA;
 748                 log_debug("Selected label: %s, flags %x\n", label, iter->flags);
 749         } else {
 750                 bool ok;
 751
 752                 /* This either returns a non-empty list or NULL */
 753                 iter->labels = bootstd_get_bootdev_order(bootstd, &ok);
 754                 if (!ok)
 755                         return log_msg_ret("ord", -ENOMEM);
 756                 log_debug("setup labels %p\n", iter->labels);
 757                 if (iter->labels) {
 758                         iter->cur_label = -1;
 759                         ret = bootdev_next_label(iter, &dev, &method_flags);
 760                 } else {
 761                         ret = bootdev_next_prio(iter, &dev);
 762                         method_flags = 0;
 763                 }
 764                 if (!dev)
 765                         return log_msg_ret("fin", -ENOENT);
 766                 log_debug("Selected bootdev: %s\n", dev->name);
 767         }
 768
 769         ret = device_probe(dev);
 770         if (ret)
 771                 return log_msg_ret("probe", ret);
 772         if (method_flagsp)
 773                 *method_flagsp = method_flags;
 774         *devp = dev;
 775
 776         return 0;
 777 }
 778
 779 static int bootdev_hunt_drv(struct bootdev_hunter *info, uint seq, bool show)
 780 {
 781         const char *name = uclass_get_name(info->uclass);
 782         struct bootstd_priv *std;
 783         int ret;
 784
 785         ret = bootstd_get_priv(&std);
 786         if (ret)
 787                 return log_msg_ret("std", ret);
 788
 789         if (!(std->hunters_used & BIT(seq))) {
 790                 if (show)
 791                         printf("Hunting with: %s\n",
 792                                uclass_get_name(info->uclass));
 793                 log_debug("Hunting with: %s\n", name);
 794                 if (info->hunt) {
 795                         ret = info->hunt(info, show);
 796                         log_debug("  - hunt result %d\n", ret);
 797                         if (ret && ret != -ENOENT)
 798                                 return ret;
 799                 }
 800                 std->hunters_used |= BIT(seq);
 801         }
 802
 803         return 0;
 804 }
 805
 806 int bootdev_hunt(const char *spec, bool show)
 807 {
 808         struct bootdev_hunter *start;
 809         const char *end;
 810         int n_ent, i;
 811         int result;
 812         size_t len;
 813
 814         start = ll_entry_start(struct bootdev_hunter, bootdev_hunter);
 815         n_ent = ll_entry_count(struct bootdev_hunter, bootdev_hunter);
 816         result = 0;
 817
 818         len = SIZE_MAX;
 819         if (spec) {
 820                 trailing_strtoln_end(spec, NULL, &end);
 821                 len = end - spec;
 822         }
 823
 824         for (i = 0; i < n_ent; i++) {
 825                 struct bootdev_hunter *info = start + i;
 826                 const char *name = uclass_get_name(info->uclass);
 827                 int ret;
 828
 829                 log_debug("looking at %.*s for %s\n",
 830                           (int)max(strlen(name), len), spec, name);
 831                 if (spec && strncmp(spec, name, max(strlen(name), len))) {
 832                         if (info->uclass != UCLASS_ETH ||
 833                             (strcmp("dhcp", spec) && strcmp("pxe", spec)))
 834                                 continue;
 835                 }
 836                 ret = bootdev_hunt_drv(info, i, show);
 837                 if (ret)
 838                         result = ret;
 839         }
 840
 841         return result;
 842 }
 843
 844 int bootdev_unhunt(enum uclass_id id)
 845 {
 846         struct bootdev_hunter *start;
 847         int n_ent, i;
 848
 849         start = ll_entry_start(struct bootdev_hunter, bootdev_hunter);
 850         n_ent = ll_entry_count(struct bootdev_hunter, bootdev_hunter);
 851         for (i = 0; i < n_ent; i++) {
 852                 struct bootdev_hunter *info = start + i;
 853
 854                 if (info->uclass == id) {
 855                         struct bootstd_priv *std;
 856                         int ret;
 857
 858                         ret = bootstd_get_priv(&std);
 859                         if (ret)
 860                                 return log_msg_ret("std", ret);
 861                         if (!(std->hunters_used & BIT(i)))
 862                                 return -EALREADY;
 863                         std->hunters_used &= ~BIT(i);
 864                         return 0;
 865                 }
 866         }
 867
 868         return -ENOENT;
 869 }
 870
 871 int bootdev_hunt_prio(enum bootdev_prio_t prio, bool show)
 872 {
 873         struct bootdev_hunter *start;
 874         int n_ent, i;
 875         int result;
 876
 877         start = ll_entry_start(struct bootdev_hunter, bootdev_hunter);
 878         n_ent = ll_entry_count(struct bootdev_hunter, bootdev_hunter);
 879         result = 0;
 880
 881         log_debug("Hunting for priority %d\n", prio);
 882         for (i = 0; i < n_ent; i++) {
 883                 struct bootdev_hunter *info = start + i;
 884                 int ret;
 885
 886                 if (prio != info->prio)
 887                         continue;
 888                 ret = bootdev_hunt_drv(info, i, show);
 889                 log_debug("bootdev_hunt_drv() return %d\n", ret);
 890                 if (ret && ret != -ENOENT)
 891                         result = ret;
 892         }
 893         log_debug("exit %d\n", result);
 894
 895         return result;
 896 }
 897
 898 void bootdev_list_hunters(struct bootstd_priv *std)
 899 {
 900         struct bootdev_hunter *orig, *start;
 901         int n_ent, i;
 902
 903         orig = ll_entry_start(struct bootdev_hunter, bootdev_hunter);
 904         n_ent = ll_entry_count(struct bootdev_hunter, bootdev_hunter);
 905
 906         /*
 907          * workaround for strange bug in clang-12 which sees all the below data
 908          * as zeroes. Any access of start seems to fix it, such as
 909          *
 910          *    printf("%p", start);
 911          *
 912          * Use memcpy() to force the correct behaviour.
 913          */
 914         memcpy(&start, &orig, sizeof(orig));
 915         printf("%4s  %4s  %-15s  %s\n", "Prio", "Used", "Uclass", "Hunter");
 916         printf("%4s  %4s  %-15s  %s\n", "----", "----", "---------------", "---------------");
 917         for (i = 0; i < n_ent; i++) {
 918                 struct bootdev_hunter *info = start + i;
 919
 920                 printf("%4d  %4s  %-15s  %s\n", info->prio,
 921                        std->hunters_used & BIT(i) ? "*" : "",
 922                        uclass_get_name(info->uclass),
 923                        info->drv ? info->drv->name : "(none)");
 924         }
 925
 926         printf("(total hunters: %d)\n", n_ent);
 927 }
 928
 929 static int bootdev_post_bind(struct udevice *dev)
 930 {
 931         struct bootdev_uc_plat *ucp = dev_get_uclass_plat(dev);
 932
 933         INIT_LIST_HEAD(&ucp->bootflow_head);
 934
 935         return 0;
 936 }
 937
 938 static int bootdev_pre_unbind(struct udevice *dev)
 939 {
 940         bootdev_clear_bootflows(dev);
 941
 942         return 0;
 943 }
 944
 945 UCLASS_DRIVER(bootdev) = {
 946         .id             = UCLASS_BOOTDEV,
 947         .name           = "bootdev",
 948         .flags          = DM_UC_FLAG_SEQ_ALIAS,
 949         .per_device_plat_auto   = sizeof(struct bootdev_uc_plat),
 950         .post_bind      = bootdev_post_bind,
 951         .pre_unbind     = bootdev_pre_unbind,
 952 };