2 * EFI device path from u-boot device-model mapping
4 * (C) Copyright 2017 Rob Clark
6 * SPDX-License-Identifier: GPL-2.0+
9 #define LOG_CATEGORY LOGL_ERR
16 #include <efi_loader.h>
20 /* template END node: */
21 static const struct efi_device_path END = {
22 .type = DEVICE_PATH_TYPE_END,
23 .sub_type = DEVICE_PATH_SUB_TYPE_END,
24 .length = sizeof(END),
28 EFI_GUID(0xe61d73b9, 0xa384, 0x4acc, \
29 0xae, 0xab, 0x82, 0xe8, 0x28, 0xf3, 0x62, 0x8b)
31 /* template ROOT node: */
32 static const struct efi_device_path_vendor ROOT = {
34 .type = DEVICE_PATH_TYPE_HARDWARE_DEVICE,
35 .sub_type = DEVICE_PATH_SUB_TYPE_VENDOR,
36 .length = sizeof(ROOT),
41 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
43 * Determine if an MMC device is an SD card.
45 * @desc block device descriptor
46 * @return true if the device is an SD card
48 static bool is_sd(struct blk_desc *desc)
50 struct mmc *mmc = find_mmc_device(desc->devnum);
55 return IS_SD(mmc) != 0U;
59 static void *dp_alloc(size_t sz)
63 if (efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, sz, &buf) !=
65 debug("EFI: ERROR: out of memory in %s\n", __func__);
74 * Iterate to next block in device-path, terminating (returning NULL)
77 struct efi_device_path *efi_dp_next(const struct efi_device_path *dp)
81 if (dp->type == DEVICE_PATH_TYPE_END)
83 dp = ((void *)dp) + dp->length;
84 if (dp->type == DEVICE_PATH_TYPE_END)
86 return (struct efi_device_path *)dp;
90 * Compare two device-paths, stopping when the shorter of the two hits
91 * an End* node. This is useful to, for example, compare a device-path
92 * representing a device with one representing a file on the device, or
93 * a device with a parent device.
95 int efi_dp_match(const struct efi_device_path *a,
96 const struct efi_device_path *b)
101 ret = memcmp(&a->length, &b->length, sizeof(a->length));
105 ret = memcmp(a, b, a->length);
118 * See UEFI spec (section 3.1.2, about short-form device-paths..
119 * tl;dr: we can have a device-path that starts with a USB WWID
120 * or USB Class node, and a few other cases which don't encode
121 * the full device path with bus hierarchy:
123 * - MESSAGING:USB_WWID
124 * - MESSAGING:USB_CLASS
129 static struct efi_device_path *shorten_path(struct efi_device_path *dp)
133 * TODO: Add MESSAGING:USB_WWID and MESSAGING:URI..
134 * in practice fallback.efi just uses MEDIA:HARD_DRIVE
135 * so not sure when we would see these other cases.
137 if (EFI_DP_TYPE(dp, MESSAGING_DEVICE, MSG_USB_CLASS) ||
138 EFI_DP_TYPE(dp, MEDIA_DEVICE, HARD_DRIVE_PATH) ||
139 EFI_DP_TYPE(dp, MEDIA_DEVICE, FILE_PATH))
142 dp = efi_dp_next(dp);
148 static struct efi_object *find_obj(struct efi_device_path *dp, bool short_path,
149 struct efi_device_path **rem)
151 struct efi_object *efiobj;
152 efi_uintn_t dp_size = efi_dp_instance_size(dp);
154 list_for_each_entry(efiobj, &efi_obj_list, link) {
155 struct efi_handler *handler;
156 struct efi_device_path *obj_dp;
159 ret = efi_search_protocol(efiobj->handle,
160 &efi_guid_device_path, &handler);
161 if (ret != EFI_SUCCESS)
163 obj_dp = handler->protocol_interface;
166 if (efi_dp_match(dp, obj_dp) == 0) {
169 * Allow partial matches, but inform
172 *rem = ((void *)dp) +
173 efi_dp_instance_size(obj_dp);
176 /* Only return on exact matches */
177 if (efi_dp_instance_size(obj_dp) ==
183 obj_dp = shorten_path(efi_dp_next(obj_dp));
184 } while (short_path && obj_dp);
191 * Find an efiobj from device-path, if 'rem' is not NULL, returns the
192 * remaining part of the device path after the matched object.
194 struct efi_object *efi_dp_find_obj(struct efi_device_path *dp,
195 struct efi_device_path **rem)
197 struct efi_object *efiobj;
199 /* Search for an exact match first */
200 efiobj = find_obj(dp, false, NULL);
202 /* Then for a fuzzy match */
204 efiobj = find_obj(dp, false, rem);
206 /* And now for a fuzzy short match */
208 efiobj = find_obj(dp, true, rem);
214 * Determine the last device path node that is not the end node.
217 * @return last node before the end node if it exists
220 const struct efi_device_path *efi_dp_last_node(const struct efi_device_path *dp)
222 struct efi_device_path *ret;
224 if (!dp || dp->type == DEVICE_PATH_TYPE_END)
227 ret = (struct efi_device_path *)dp;
228 dp = efi_dp_next(dp);
233 /* get size of the first device path instance excluding end node */
234 efi_uintn_t efi_dp_instance_size(const struct efi_device_path *dp)
238 if (!dp || dp->type == DEVICE_PATH_TYPE_END)
242 dp = efi_dp_next(dp);
248 /* get size of multi-instance device path excluding end node */
249 efi_uintn_t efi_dp_size(const struct efi_device_path *dp)
251 const struct efi_device_path *p = dp;
255 while (p->type != DEVICE_PATH_TYPE_END ||
256 p->sub_type != DEVICE_PATH_SUB_TYPE_END)
257 p = (void *)p + p->length;
259 return (void *)p - (void *)dp;
262 /* copy multi-instance device path */
263 struct efi_device_path *efi_dp_dup(const struct efi_device_path *dp)
265 struct efi_device_path *ndp;
266 size_t sz = efi_dp_size(dp) + sizeof(END);
279 struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
280 const struct efi_device_path *dp2)
282 struct efi_device_path *ret;
285 /* return an end node */
286 ret = efi_dp_dup(&END);
288 ret = efi_dp_dup(dp2);
290 ret = efi_dp_dup(dp1);
292 /* both dp1 and dp2 are non-null */
293 unsigned sz1 = efi_dp_size(dp1);
294 unsigned sz2 = efi_dp_size(dp2);
295 void *p = dp_alloc(sz1 + sz2 + sizeof(END));
299 /* the end node of the second device path has to be retained */
300 memcpy(p + sz1, dp2, sz2 + sizeof(END));
307 struct efi_device_path *efi_dp_append_node(const struct efi_device_path *dp,
308 const struct efi_device_path *node)
310 struct efi_device_path *ret;
313 ret = efi_dp_dup(&END);
315 ret = efi_dp_dup(dp);
317 size_t sz = node->length;
318 void *p = dp_alloc(sz + sizeof(END));
322 memcpy(p + sz, &END, sizeof(END));
325 /* both dp and node are non-null */
326 size_t sz = efi_dp_size(dp);
327 void *p = dp_alloc(sz + node->length + sizeof(END));
331 memcpy(p + sz, node, node->length);
332 memcpy(p + sz + node->length, &END, sizeof(END));
339 struct efi_device_path *efi_dp_create_device_node(const u8 type,
343 struct efi_device_path *ret;
345 ret = dp_alloc(length);
349 ret->sub_type = sub_type;
350 ret->length = length;
354 struct efi_device_path *efi_dp_append_instance(
355 const struct efi_device_path *dp,
356 const struct efi_device_path *dpi)
359 struct efi_device_path *p, *ret;
364 return efi_dp_dup(dpi);
365 sz = efi_dp_size(dp);
366 szi = efi_dp_instance_size(dpi);
367 p = dp_alloc(sz + szi + 2 * sizeof(END));
371 memcpy(p, dp, sz + sizeof(END));
373 p->sub_type = DEVICE_PATH_SUB_TYPE_INSTANCE_END;
374 p = (void *)p + sizeof(END);
377 memcpy(p, &END, sizeof(END));
381 struct efi_device_path *efi_dp_get_next_instance(struct efi_device_path **dp,
385 struct efi_device_path *p;
392 sz = efi_dp_instance_size(*dp);
393 p = dp_alloc(sz + sizeof(END));
396 memcpy(p, *dp, sz + sizeof(END));
397 *dp = (void *)*dp + sz;
398 if ((*dp)->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END)
399 *dp = (void *)*dp + sizeof(END);
403 *size = sz + sizeof(END);
407 bool efi_dp_is_multi_instance(const struct efi_device_path *dp)
409 const struct efi_device_path *p = dp;
413 while (p->type != DEVICE_PATH_TYPE_END)
414 p = (void *)p + p->length;
415 return p->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END;
419 /* size of device-path not including END node for device and all parents
420 * up to the root device.
422 static unsigned dp_size(struct udevice *dev)
424 if (!dev || !dev->driver)
427 switch (dev->driver->id) {
429 case UCLASS_SIMPLE_BUS:
430 /* stop traversing parents at this point: */
433 return dp_size(dev->parent) +
434 sizeof(struct efi_device_path_mac_addr);
437 switch (dev->parent->uclass->uc_drv->id) {
440 return dp_size(dev->parent) +
441 sizeof(struct efi_device_path_atapi);
443 #if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
445 return dp_size(dev->parent) +
446 sizeof(struct efi_device_path_scsi);
448 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
450 return dp_size(dev->parent) +
451 sizeof(struct efi_device_path_sd_mmc_path);
454 return dp_size(dev->parent);
457 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
459 return dp_size(dev->parent) +
460 sizeof(struct efi_device_path_sd_mmc_path);
462 case UCLASS_MASS_STORAGE:
464 return dp_size(dev->parent) +
465 sizeof(struct efi_device_path_usb_class);
467 /* just skip over unknown classes: */
468 return dp_size(dev->parent);
473 * Recursively build a device path.
475 * @buf pointer to the end of the device path
477 * @return pointer to the end of the device path
479 static void *dp_fill(void *buf, struct udevice *dev)
481 if (!dev || !dev->driver)
484 switch (dev->driver->id) {
486 case UCLASS_SIMPLE_BUS: {
487 /* stop traversing parents at this point: */
488 struct efi_device_path_vendor *vdp = buf;
494 struct efi_device_path_mac_addr *dp =
495 dp_fill(buf, dev->parent);
496 struct eth_pdata *pdata = dev->platdata;
498 dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
499 dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
500 dp->dp.length = sizeof(*dp);
501 memset(&dp->mac, 0, sizeof(dp->mac));
502 /* We only support IPv4 */
503 memcpy(&dp->mac, &pdata->enetaddr, ARP_HLEN);
511 switch (dev->parent->uclass->uc_drv->id) {
514 struct efi_device_path_atapi *dp =
515 dp_fill(buf, dev->parent);
516 struct blk_desc *desc = dev_get_uclass_platdata(dev);
518 dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
519 dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_ATAPI;
520 dp->dp.length = sizeof(*dp);
521 dp->logical_unit_number = desc->devnum;
522 dp->primary_secondary = IDE_BUS(desc->devnum);
523 dp->slave_master = desc->devnum %
524 (CONFIG_SYS_IDE_MAXDEVICE /
525 CONFIG_SYS_IDE_MAXBUS);
529 #if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
531 struct efi_device_path_scsi *dp =
532 dp_fill(buf, dev->parent);
533 struct blk_desc *desc = dev_get_uclass_platdata(dev);
535 dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
536 dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_SCSI;
537 dp->dp.length = sizeof(*dp);
538 dp->logical_unit_number = desc->lun;
539 dp->target_id = desc->target;
543 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
545 struct efi_device_path_sd_mmc_path *sddp =
546 dp_fill(buf, dev->parent);
547 struct blk_desc *desc = dev_get_uclass_platdata(dev);
549 sddp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
550 sddp->dp.sub_type = is_sd(desc) ?
551 DEVICE_PATH_SUB_TYPE_MSG_SD :
552 DEVICE_PATH_SUB_TYPE_MSG_MMC;
553 sddp->dp.length = sizeof(*sddp);
554 sddp->slot_number = dev->seq;
559 debug("%s(%u) %s: unhandled parent class: %s (%u)\n",
560 __FILE__, __LINE__, __func__,
561 dev->name, dev->parent->uclass->uc_drv->id);
562 return dp_fill(buf, dev->parent);
565 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
567 struct efi_device_path_sd_mmc_path *sddp =
568 dp_fill(buf, dev->parent);
569 struct mmc *mmc = mmc_get_mmc_dev(dev);
570 struct blk_desc *desc = mmc_get_blk_desc(mmc);
572 sddp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
573 sddp->dp.sub_type = is_sd(desc) ?
574 DEVICE_PATH_SUB_TYPE_MSG_SD :
575 DEVICE_PATH_SUB_TYPE_MSG_MMC;
576 sddp->dp.length = sizeof(*sddp);
577 sddp->slot_number = dev->seq;
582 case UCLASS_MASS_STORAGE:
583 case UCLASS_USB_HUB: {
584 struct efi_device_path_usb_class *udp =
585 dp_fill(buf, dev->parent);
586 struct usb_device *udev = dev_get_parent_priv(dev);
587 struct usb_device_descriptor *desc = &udev->descriptor;
589 udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
590 udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS;
591 udp->dp.length = sizeof(*udp);
592 udp->vendor_id = desc->idVendor;
593 udp->product_id = desc->idProduct;
594 udp->device_class = desc->bDeviceClass;
595 udp->device_subclass = desc->bDeviceSubClass;
596 udp->device_protocol = desc->bDeviceProtocol;
601 debug("%s(%u) %s: unhandled device class: %s (%u)\n",
602 __FILE__, __LINE__, __func__,
603 dev->name, dev->driver->id);
604 return dp_fill(buf, dev->parent);
608 /* Construct a device-path from a device: */
609 struct efi_device_path *efi_dp_from_dev(struct udevice *dev)
613 start = buf = dp_alloc(dp_size(dev) + sizeof(END));
616 buf = dp_fill(buf, dev);
617 *((struct efi_device_path *)buf) = END;
623 static unsigned dp_part_size(struct blk_desc *desc, int part)
630 int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
633 dev = desc->bdev->parent;
634 dpsize = dp_size(dev);
637 dpsize = sizeof(ROOT) + sizeof(struct efi_device_path_usb);
640 if (part == 0) /* the actual disk, not a partition */
643 if (desc->part_type == PART_TYPE_ISO)
644 dpsize += sizeof(struct efi_device_path_cdrom_path);
646 dpsize += sizeof(struct efi_device_path_hard_drive_path);
652 * Create a device node for a block device partition.
654 * @buf buffer to which the device path is wirtten
655 * @desc block device descriptor
656 * @part partition number, 0 identifies a block device
658 static void *dp_part_node(void *buf, struct blk_desc *desc, int part)
660 disk_partition_t info;
662 part_get_info(desc, part, &info);
664 if (desc->part_type == PART_TYPE_ISO) {
665 struct efi_device_path_cdrom_path *cddp = buf;
667 cddp->boot_entry = part;
668 cddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
669 cddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CDROM_PATH;
670 cddp->dp.length = sizeof(*cddp);
671 cddp->partition_start = info.start;
672 cddp->partition_end = info.size;
676 struct efi_device_path_hard_drive_path *hddp = buf;
678 hddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
679 hddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH;
680 hddp->dp.length = sizeof(*hddp);
681 hddp->partition_number = part;
682 hddp->partition_start = info.start;
683 hddp->partition_end = info.size;
684 if (desc->part_type == PART_TYPE_EFI)
685 hddp->partmap_type = 2;
687 hddp->partmap_type = 1;
689 switch (desc->sig_type) {
692 hddp->signature_type = 0;
693 memset(hddp->partition_signature, 0,
694 sizeof(hddp->partition_signature));
697 hddp->signature_type = 1;
698 memset(hddp->partition_signature, 0,
699 sizeof(hddp->partition_signature));
700 memcpy(hddp->partition_signature, &desc->mbr_sig,
701 sizeof(desc->mbr_sig));
704 hddp->signature_type = 2;
705 memcpy(hddp->partition_signature, &desc->guid_sig,
706 sizeof(hddp->partition_signature));
717 * Create a device path for a block device or one of its partitions.
719 * @buf buffer to which the device path is wirtten
720 * @desc block device descriptor
721 * @part partition number, 0 identifies a block device
723 static void *dp_part_fill(void *buf, struct blk_desc *desc, int part)
728 int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
731 dev = desc->bdev->parent;
732 buf = dp_fill(buf, dev);
736 * We *could* make a more accurate path, by looking at if_type
737 * and handling all the different cases like we do for non-
738 * legacy (ie CONFIG_BLK=y) case. But most important thing
739 * is just to have a unique device-path for if_type+devnum.
740 * So map things to a fictitious USB device.
742 struct efi_device_path_usb *udp;
744 memcpy(buf, &ROOT, sizeof(ROOT));
748 udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
749 udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB;
750 udp->dp.length = sizeof(*udp);
751 udp->parent_port_number = desc->if_type;
752 udp->usb_interface = desc->devnum;
756 if (part == 0) /* the actual disk, not a partition */
759 return dp_part_node(buf, desc, part);
762 /* Construct a device-path from a partition on a blk device: */
763 struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part)
767 start = buf = dp_alloc(dp_part_size(desc, part) + sizeof(END));
771 buf = dp_part_fill(buf, desc, part);
773 *((struct efi_device_path *)buf) = END;
779 * Create a device node for a block device partition.
781 * @buf buffer to which the device path is wirtten
782 * @desc block device descriptor
783 * @part partition number, 0 identifies a block device
785 struct efi_device_path *efi_dp_part_node(struct blk_desc *desc, int part)
790 if (desc->part_type == PART_TYPE_ISO)
791 dpsize = sizeof(struct efi_device_path_cdrom_path);
793 dpsize = sizeof(struct efi_device_path_hard_drive_path);
794 buf = dp_alloc(dpsize);
796 dp_part_node(buf, desc, part);
801 /* convert path to an UEFI style path (ie. DOS style backslashes and utf16) */
802 static void path_to_uefi(u16 *uefi, const char *path)
814 * If desc is NULL, this creates a path with only the file component,
815 * otherwise it creates a full path with both device and file components
817 struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,
820 struct efi_device_path_file_path *fp;
822 unsigned dpsize = 0, fpsize;
825 dpsize = dp_part_size(desc, part);
827 fpsize = sizeof(struct efi_device_path) + 2 * (strlen(path) + 1);
830 start = buf = dp_alloc(dpsize + sizeof(END));
835 buf = dp_part_fill(buf, desc, part);
839 fp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
840 fp->dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
841 fp->dp.length = fpsize;
842 path_to_uefi(fp->str, path);
845 *((struct efi_device_path *)buf) = END;
851 struct efi_device_path *efi_dp_from_eth(void)
853 #ifndef CONFIG_DM_ETH
854 struct efi_device_path_mac_addr *ndp;
859 assert(eth_get_dev());
862 dpsize += dp_size(eth_get_dev());
864 dpsize += sizeof(ROOT);
865 dpsize += sizeof(*ndp);
868 start = buf = dp_alloc(dpsize + sizeof(END));
873 buf = dp_fill(buf, eth_get_dev());
875 memcpy(buf, &ROOT, sizeof(ROOT));
879 ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
880 ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
881 ndp->dp.length = sizeof(*ndp);
882 ndp->if_type = 1; /* Ethernet */
883 memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
887 *((struct efi_device_path *)buf) = END;
893 /* Construct a device-path for memory-mapped image */
894 struct efi_device_path *efi_dp_from_mem(uint32_t memory_type,
895 uint64_t start_address,
896 uint64_t end_address)
898 struct efi_device_path_memory *mdp;
901 start = buf = dp_alloc(sizeof(*mdp) + sizeof(END));
906 mdp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
907 mdp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MEMORY;
908 mdp->dp.length = sizeof(*mdp);
909 mdp->memory_type = memory_type;
910 mdp->start_address = start_address;
911 mdp->end_address = end_address;
914 *((struct efi_device_path *)buf) = END;
920 * Helper to split a full device path (containing both device and file
921 * parts) into it's constituent parts.
923 efi_status_t efi_dp_split_file_path(struct efi_device_path *full_path,
924 struct efi_device_path **device_path,
925 struct efi_device_path **file_path)
927 struct efi_device_path *p, *dp, *fp;
931 dp = efi_dp_dup(full_path);
933 return EFI_OUT_OF_RESOURCES;
935 while (!EFI_DP_TYPE(p, MEDIA_DEVICE, FILE_PATH)) {
938 return EFI_OUT_OF_RESOURCES;
942 return EFI_OUT_OF_RESOURCES;
943 p->type = DEVICE_PATH_TYPE_END;
944 p->sub_type = DEVICE_PATH_SUB_TYPE_END;
945 p->length = sizeof(*p);