[people/ms/u-boot.git] / lib / efi_loader / efi_device_path.c

/*
 * EFI device path from u-boot device-model mapping
 *
 * (C) Copyright 2017 Rob Clark
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <blk.h>
#include <dm.h>
#include <usb.h>
#include <mmc.h>
#include <efi_loader.h>
#include <inttypes.h>
#include <part.h>

/* template END node: */
static const struct efi_device_path END = {
	.type     = DEVICE_PATH_TYPE_END,
	.sub_type = DEVICE_PATH_SUB_TYPE_END,
	.length   = sizeof(END),
};

#define U_BOOT_GUID \
	EFI_GUID(0xe61d73b9, 0xa384, 0x4acc, \
		 0xae, 0xab, 0x82, 0xe8, 0x28, 0xf3, 0x62, 0x8b)

/* template ROOT node: */
static const struct efi_device_path_vendor ROOT = {
	.dp = {
		.type     = DEVICE_PATH_TYPE_HARDWARE_DEVICE,
		.sub_type = DEVICE_PATH_SUB_TYPE_VENDOR,
		.length   = sizeof(ROOT),
	},
	.guid = U_BOOT_GUID,
};

#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
/*
 * Determine if an MMC device is an SD card.
 *
 * @desc	block device descriptor
 * @return	true if the device is an SD card
 */
static bool is_sd(struct blk_desc *desc)
{
	struct mmc *mmc = find_mmc_device(desc->devnum);

	if (!mmc)
		return false;

	return IS_SD(mmc) != 0U;
}
#endif

static void *dp_alloc(size_t sz)
{
	void *buf;

	if (efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, sz, &buf) != EFI_SUCCESS)
		return NULL;

	return buf;
}

/*
 * Iterate to next block in device-path, terminating (returning NULL)
 * at /End* node.
 */
struct efi_device_path *efi_dp_next(const struct efi_device_path *dp)
{
	if (dp == NULL)
		return NULL;
	if (dp->type == DEVICE_PATH_TYPE_END)
		return NULL;
	dp = ((void *)dp) + dp->length;
	if (dp->type == DEVICE_PATH_TYPE_END)
		return NULL;
	return (struct efi_device_path *)dp;
}

/*
 * Compare two device-paths, stopping when the shorter of the two hits
 * an End* node.  This is useful to, for example, compare a device-path
 * representing a device with one representing a file on the device, or
 * a device with a parent device.
 */
int efi_dp_match(const struct efi_device_path *a,
		 const struct efi_device_path *b)
{
	while (1) {
		int ret;

		ret = memcmp(&a->length, &b->length, sizeof(a->length));
		if (ret)
			return ret;

		ret = memcmp(a, b, a->length);
		if (ret)
			return ret;

		a = efi_dp_next(a);
		b = efi_dp_next(b);

		if (!a || !b)
			return 0;
	}
}


/*
 * See UEFI spec (section 3.1.2, about short-form device-paths..
 * tl;dr: we can have a device-path that starts with a USB WWID
 * or USB Class node, and a few other cases which don't encode
 * the full device path with bus hierarchy:
 *
 *   - MESSAGING:USB_WWID
 *   - MESSAGING:USB_CLASS
 *   - MEDIA:FILE_PATH
 *   - MEDIA:HARD_DRIVE
 *   - MESSAGING:URI
 */
static struct efi_device_path *shorten_path(struct efi_device_path *dp)
{
	while (dp) {
		/*
		 * TODO: Add MESSAGING:USB_WWID and MESSAGING:URI..
		 * in practice fallback.efi just uses MEDIA:HARD_DRIVE
		 * so not sure when we would see these other cases.
		 */
		if (EFI_DP_TYPE(dp, MESSAGING_DEVICE, MSG_USB_CLASS) ||
		    EFI_DP_TYPE(dp, MEDIA_DEVICE, HARD_DRIVE_PATH) ||
		    EFI_DP_TYPE(dp, MEDIA_DEVICE, FILE_PATH))
			return dp;

		dp = efi_dp_next(dp);
	}

	return dp;
}

static struct efi_object *find_obj(struct efi_device_path *dp, bool short_path,
				   struct efi_device_path **rem)
{
	struct efi_object *efiobj;
	unsigned int dp_size = efi_dp_size(dp);

	list_for_each_entry(efiobj, &efi_obj_list, link) {
		struct efi_handler *handler;
		struct efi_device_path *obj_dp;
		efi_status_t ret;

		ret = efi_search_protocol(efiobj->handle,
					  &efi_guid_device_path, &handler);
		if (ret != EFI_SUCCESS)
			continue;
		obj_dp = handler->protocol_interface;

		do {
			if (efi_dp_match(dp, obj_dp) == 0) {
				if (rem) {
					/*
					 * Allow partial matches, but inform
					 * the caller.
					 */
					*rem = ((void *)dp) +
						efi_dp_size(obj_dp);
					return efiobj;
				} else {
					/* Only return on exact matches */
					if (efi_dp_size(obj_dp) == dp_size)
						return efiobj;
				}
			}

			obj_dp = shorten_path(efi_dp_next(obj_dp));
		} while (short_path && obj_dp);
	}

	return NULL;
}


/*
 * Find an efiobj from device-path, if 'rem' is not NULL, returns the
 * remaining part of the device path after the matched object.
 */
struct efi_object *efi_dp_find_obj(struct efi_device_path *dp,
				   struct efi_device_path **rem)
{
	struct efi_object *efiobj;

	/* Search for an exact match first */
	efiobj = find_obj(dp, false, NULL);

	/* Then for a fuzzy match */
	if (!efiobj)
		efiobj = find_obj(dp, false, rem);

	/* And now for a fuzzy short match */
	if (!efiobj)
		efiobj = find_obj(dp, true, rem);

	return efiobj;
}

/* return size not including End node: */
unsigned efi_dp_size(const struct efi_device_path *dp)
{
	unsigned sz = 0;

	while (dp) {
		sz += dp->length;
		dp = efi_dp_next(dp);
	}

	return sz;
}

struct efi_device_path *efi_dp_dup(const struct efi_device_path *dp)
{
	struct efi_device_path *ndp;
	unsigned sz = efi_dp_size(dp) + sizeof(END);

	if (!dp)
		return NULL;

	ndp = dp_alloc(sz);
	memcpy(ndp, dp, sz);

	return ndp;
}

struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
				      const struct efi_device_path *dp2)
{
	struct efi_device_path *ret;

	if (!dp1) {
		ret = efi_dp_dup(dp2);
	} else if (!dp2) {
		ret = efi_dp_dup(dp1);
	} else {
		/* both dp1 and dp2 are non-null */
		unsigned sz1 = efi_dp_size(dp1);
		unsigned sz2 = efi_dp_size(dp2);
		void *p = dp_alloc(sz1 + sz2 + sizeof(END));
		memcpy(p, dp1, sz1);
		memcpy(p + sz1, dp2, sz2);
		memcpy(p + sz1 + sz2, &END, sizeof(END));
		ret = p;
	}

	return ret;
}

struct efi_device_path *efi_dp_append_node(const struct efi_device_path *dp,
					   const struct efi_device_path *node)
{
	struct efi_device_path *ret;

	if (!node && !dp) {
		ret = efi_dp_dup(&END);
	} else if (!node) {
		ret = efi_dp_dup(dp);
	} else if (!dp) {
		unsigned sz = node->length;
		void *p = dp_alloc(sz + sizeof(END));
		memcpy(p, node, sz);
		memcpy(p + sz, &END, sizeof(END));
		ret = p;
	} else {
		/* both dp and node are non-null */
		unsigned sz = efi_dp_size(dp);
		void *p = dp_alloc(sz + node->length + sizeof(END));
		memcpy(p, dp, sz);
		memcpy(p + sz, node, node->length);
		memcpy(p + sz + node->length, &END, sizeof(END));
		ret = p;
	}

	return ret;
}

#ifdef CONFIG_DM
/* size of device-path not including END node for device and all parents
 * up to the root device.
 */
static unsigned dp_size(struct udevice *dev)
{
	if (!dev || !dev->driver)
		return sizeof(ROOT);

	switch (dev->driver->id) {
	case UCLASS_ROOT:
	case UCLASS_SIMPLE_BUS:
		/* stop traversing parents at this point: */
		return sizeof(ROOT);
#ifdef CONFIG_BLK
	case UCLASS_BLK:
		switch (dev->parent->uclass->uc_drv->id) {
#ifdef CONFIG_IDE
		case UCLASS_IDE:
			return dp_size(dev->parent) +
				sizeof(struct efi_device_path_atapi);
#endif
#if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
		case UCLASS_SCSI:
			return dp_size(dev->parent) +
				sizeof(struct efi_device_path_scsi);
#endif
		default:
			return dp_size(dev->parent);
		}
#endif
	case UCLASS_MMC:
		return dp_size(dev->parent) +
			sizeof(struct efi_device_path_sd_mmc_path);
	case UCLASS_MASS_STORAGE:
	case UCLASS_USB_HUB:
		return dp_size(dev->parent) +
			sizeof(struct efi_device_path_usb_class);
	default:
		/* just skip over unknown classes: */
		return dp_size(dev->parent);
	}
}

/*
 * Recursively build a device path.
 *
 * @buf		pointer to the end of the device path
 * @dev		device
 * @return	pointer to the end of the device path
 */
static void *dp_fill(void *buf, struct udevice *dev)
{
	if (!dev || !dev->driver)
		return buf;

	switch (dev->driver->id) {
	case UCLASS_ROOT:
	case UCLASS_SIMPLE_BUS: {
		/* stop traversing parents at this point: */
		struct efi_device_path_vendor *vdp = buf;
		*vdp = ROOT;
		return &vdp[1];
	}
#ifdef CONFIG_BLK
	case UCLASS_BLK:
		switch (dev->parent->uclass->uc_drv->id) {
#ifdef CONFIG_IDE
		case UCLASS_IDE: {
			struct efi_device_path_atapi *dp =
			dp_fill(buf, dev->parent);
			struct blk_desc *desc = dev_get_uclass_platdata(dev);

			dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
			dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_ATAPI;
			dp->dp.length = sizeof(*dp);
			dp->logical_unit_number = desc->devnum;
			dp->primary_secondary = IDE_BUS(desc->devnum);
			dp->slave_master = desc->devnum %
				(CONFIG_SYS_IDE_MAXDEVICE /
				 CONFIG_SYS_IDE_MAXBUS);
			return &dp[1];
			}
#endif
#if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
		case UCLASS_SCSI: {
			struct efi_device_path_scsi *dp =
				dp_fill(buf, dev->parent);
			struct blk_desc *desc = dev_get_uclass_platdata(dev);

			dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
			dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_SCSI;
			dp->dp.length = sizeof(*dp);
			dp->logical_unit_number = desc->lun;
			dp->target_id = desc->target;
			return &dp[1];
			}
#endif
		default:
			printf("unhandled parent class: %s (%u)\n",
			       dev->name, dev->driver->id);
			return dp_fill(buf, dev->parent);
		}
#endif
#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
	case UCLASS_MMC: {
		struct efi_device_path_sd_mmc_path *sddp =
			dp_fill(buf, dev->parent);
		struct mmc *mmc = mmc_get_mmc_dev(dev);
		struct blk_desc *desc = mmc_get_blk_desc(mmc);

		sddp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
		sddp->dp.sub_type = is_sd(desc) ?
			DEVICE_PATH_SUB_TYPE_MSG_SD :
			DEVICE_PATH_SUB_TYPE_MSG_MMC;
		sddp->dp.length   = sizeof(*sddp);
		sddp->slot_number = dev->seq;

		return &sddp[1];
	}
#endif
	case UCLASS_MASS_STORAGE:
	case UCLASS_USB_HUB: {
		struct efi_device_path_usb_class *udp =
			dp_fill(buf, dev->parent);
		struct usb_device *udev = dev_get_parent_priv(dev);
		struct usb_device_descriptor *desc = &udev->descriptor;

		udp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
		udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS;
		udp->dp.length   = sizeof(*udp);
		udp->vendor_id   = desc->idVendor;
		udp->product_id  = desc->idProduct;
		udp->device_class    = desc->bDeviceClass;
		udp->device_subclass = desc->bDeviceSubClass;
		udp->device_protocol = desc->bDeviceProtocol;

		return &udp[1];
	}
	default:
		debug("unhandled device class: %s (%u)\n",
		      dev->name, dev->driver->id);
		return dp_fill(buf, dev->parent);
	}
}

/* Construct a device-path from a device: */
struct efi_device_path *efi_dp_from_dev(struct udevice *dev)
{
	void *buf, *start;

	start = buf = dp_alloc(dp_size(dev) + sizeof(END));
	buf = dp_fill(buf, dev);
	*((struct efi_device_path *)buf) = END;

	return start;
}
#endif

static unsigned dp_part_size(struct blk_desc *desc, int part)
{
	unsigned dpsize;

#ifdef CONFIG_BLK
	{
		struct udevice *dev;
		int ret = blk_find_device(desc->if_type, desc->devnum, &dev);

		if (ret)
			dev = desc->bdev->parent;
		dpsize = dp_size(dev);
	}
#else
	dpsize = sizeof(ROOT) + sizeof(struct efi_device_path_usb);
#endif

	if (part == 0) /* the actual disk, not a partition */
		return dpsize;

	if (desc->part_type == PART_TYPE_ISO)
		dpsize += sizeof(struct efi_device_path_cdrom_path);
	else
		dpsize += sizeof(struct efi_device_path_hard_drive_path);

	return dpsize;
}

/*
 * Create a device path for a block device or one of its partitions.
 *
 * @buf		buffer to which the device path is wirtten
 * @desc	block device descriptor
 * @part	partition number, 0 identifies a block device
 */
static void *dp_part_fill(void *buf, struct blk_desc *desc, int part)
{
	disk_partition_t info;

#ifdef CONFIG_BLK
	{
		struct udevice *dev;
		int ret = blk_find_device(desc->if_type, desc->devnum, &dev);

		if (ret)
			dev = desc->bdev->parent;
		buf = dp_fill(buf, dev);
	}
#else
	/*
	 * We *could* make a more accurate path, by looking at if_type
	 * and handling all the different cases like we do for non-
	 * legacy (ie CONFIG_BLK=y) case.  But most important thing
	 * is just to have a unique device-path for if_type+devnum.
	 * So map things to a fictitious USB device.
	 */
	struct efi_device_path_usb *udp;

	memcpy(buf, &ROOT, sizeof(ROOT));
	buf += sizeof(ROOT);

	udp = buf;
	udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
	udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB;
	udp->dp.length = sizeof(*udp);
	udp->parent_port_number = desc->if_type;
	udp->usb_interface = desc->devnum;
	buf = &udp[1];
#endif

	if (part == 0) /* the actual disk, not a partition */
		return buf;

	part_get_info(desc, part, &info);

	if (desc->part_type == PART_TYPE_ISO) {
		struct efi_device_path_cdrom_path *cddp = buf;

		cddp->boot_entry = part;
		cddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
		cddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CDROM_PATH;
		cddp->dp.length = sizeof(*cddp);
		cddp->partition_start = info.start;
		cddp->partition_end = info.size;

		buf = &cddp[1];
	} else {
		struct efi_device_path_hard_drive_path *hddp = buf;

		hddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
		hddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH;
		hddp->dp.length = sizeof(*hddp);
		hddp->partition_number = part;
		hddp->partition_start = info.start;
		hddp->partition_end = info.size;
		if (desc->part_type == PART_TYPE_EFI)
			hddp->partmap_type = 2;
		else
			hddp->partmap_type = 1;

		switch (desc->sig_type) {
		case SIG_TYPE_NONE:
		default:
			hddp->signature_type = 0;
			memset(hddp->partition_signature, 0,
			       sizeof(hddp->partition_signature));
			break;
		case SIG_TYPE_MBR:
			hddp->signature_type = 1;
			memset(hddp->partition_signature, 0,
			       sizeof(hddp->partition_signature));
			memcpy(hddp->partition_signature, &desc->mbr_sig,
			       sizeof(desc->mbr_sig));
			break;
		case SIG_TYPE_GUID:
			hddp->signature_type = 2;
			memcpy(hddp->partition_signature, &desc->guid_sig,
			       sizeof(hddp->partition_signature));
			break;
		}

		buf = &hddp[1];
	}

	return buf;
}


/* Construct a device-path from a partition on a blk device: */
struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part)
{
	void *buf, *start;

	start = buf = dp_alloc(dp_part_size(desc, part) + sizeof(END));

	buf = dp_part_fill(buf, desc, part);

	*((struct efi_device_path *)buf) = END;

	return start;
}

/* convert path to an UEFI style path (ie. DOS style backslashes and utf16) */
static void path_to_uefi(u16 *uefi, const char *path)
{
	while (*path) {
		char c = *(path++);
		if (c == '/')
			c = '\\';
		*(uefi++) = c;
	}
	*uefi = '\0';
}

/*
 * If desc is NULL, this creates a path with only the file component,
 * otherwise it creates a full path with both device and file components
 */
struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,
		const char *path)
{
	struct efi_device_path_file_path *fp;
	void *buf, *start;
	unsigned dpsize = 0, fpsize;

	if (desc)
		dpsize = dp_part_size(desc, part);

	fpsize = sizeof(struct efi_device_path) + 2 * (strlen(path) + 1);
	dpsize += fpsize;

	start = buf = dp_alloc(dpsize + sizeof(END));

	if (desc)
		buf = dp_part_fill(buf, desc, part);

	/* add file-path: */
	fp = buf;
	fp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
	fp->dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
	fp->dp.length = fpsize;
	path_to_uefi(fp->str, path);
	buf += fpsize;

	*((struct efi_device_path *)buf) = END;

	return start;
}

#ifdef CONFIG_NET
struct efi_device_path *efi_dp_from_eth(void)
{
	struct efi_device_path_mac_addr *ndp;
	void *buf, *start;
	unsigned dpsize = 0;

	assert(eth_get_dev());

#ifdef CONFIG_DM_ETH
	dpsize += dp_size(eth_get_dev());
#else
	dpsize += sizeof(ROOT);
#endif
	dpsize += sizeof(*ndp);

	start = buf = dp_alloc(dpsize + sizeof(END));

#ifdef CONFIG_DM_ETH
	buf = dp_fill(buf, eth_get_dev());
#else
	memcpy(buf, &ROOT, sizeof(ROOT));
	buf += sizeof(ROOT);
#endif

	ndp = buf;
	ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
	ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
	ndp->dp.length = sizeof(*ndp);
	memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
	buf = &ndp[1];

	*((struct efi_device_path *)buf) = END;

	return start;
}
#endif

/* Construct a device-path for memory-mapped image */
struct efi_device_path *efi_dp_from_mem(uint32_t memory_type,
					uint64_t start_address,
					uint64_t end_address)
{
	struct efi_device_path_memory *mdp;
	void *buf, *start;

	start = buf = dp_alloc(sizeof(*mdp) + sizeof(END));

	mdp = buf;
	mdp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
	mdp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MEMORY;
	mdp->dp.length = sizeof(*mdp);
	mdp->memory_type = memory_type;
	mdp->start_address = start_address;
	mdp->end_address = end_address;
	buf = &mdp[1];

	*((struct efi_device_path *)buf) = END;

	return start;
}

/*
 * Helper to split a full device path (containing both device and file
 * parts) into it's constituent parts.
 */
void efi_dp_split_file_path(struct efi_device_path *full_path,
			    struct efi_device_path **device_path,
			    struct efi_device_path **file_path)
{
	struct efi_device_path *p, *dp, *fp;

	dp = efi_dp_dup(full_path);
	p = dp;
	while (!EFI_DP_TYPE(p, MEDIA_DEVICE, FILE_PATH))
		p = efi_dp_next(p);
	fp = efi_dp_dup(p);

	p->type = DEVICE_PATH_TYPE_END;
	p->sub_type = DEVICE_PATH_SUB_TYPE_END;
	p->length = sizeof(*p);

	*device_path = dp;
	*file_path = fp;
}
Commit	Line	Data
b66c60dd RC	1	/*
	2	* EFI device path from u-boot device-model mapping
	3	*
	4	* (C) Copyright 2017 Rob Clark
	5	*
	6	* SPDX-License-Identifier: GPL-2.0+
	7	*/
	8
	9	#include <common.h>
	10	#include <blk.h>
	11	#include <dm.h>
	12	#include <usb.h>
	13	#include <mmc.h>
	14	#include <efi_loader.h>
	15	#include <inttypes.h>
	16	#include <part.h>
	17
	18	/* template END node: */
	19	static const struct efi_device_path END = {
	20	.type = DEVICE_PATH_TYPE_END,
	21	.sub_type = DEVICE_PATH_SUB_TYPE_END,
	22	.length = sizeof(END),
	23	};
	24
	25	#define U_BOOT_GUID \
	26	EFI_GUID(0xe61d73b9, 0xa384, 0x4acc, \
	27	0xae, 0xab, 0x82, 0xe8, 0x28, 0xf3, 0x62, 0x8b)
	28
	29	/* template ROOT node: */
	30	static const struct efi_device_path_vendor ROOT = {
	31	.dp = {
	32	.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE,
	33	.sub_type = DEVICE_PATH_SUB_TYPE_VENDOR,
	34	.length = sizeof(ROOT),
	35	},
	36	.guid = U_BOOT_GUID,
	37	};
	38
66b051d5 HS	39	#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
	40	/*
	41	* Determine if an MMC device is an SD card.
	42	*
	43	* @desc block device descriptor
	44	* @return true if the device is an SD card
	45	*/
	46	static bool is_sd(struct blk_desc *desc)
	47	{
	48	struct mmc *mmc = find_mmc_device(desc->devnum);
	49
	50	if (!mmc)
	51	return false;
	52
	53	return IS_SD(mmc) != 0U;
	54	}
	55	#endif
	56
b66c60dd RC	57	static void *dp_alloc(size_t sz)
	58	{
	59	void *buf;
	60
	61	if (efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, sz, &buf) != EFI_SUCCESS)
	62	return NULL;
	63
	64	return buf;
	65	}
	66
	67	/*
	68	* Iterate to next block in device-path, terminating (returning NULL)
	69	* at /End* node.
	70	*/
	71	struct efi_device_path efi_dp_next(const struct efi_device_path dp)
	72	{
	73	if (dp == NULL)
	74	return NULL;
	75	if (dp->type == DEVICE_PATH_TYPE_END)
	76	return NULL;
	77	dp = ((void *)dp) + dp->length;
	78	if (dp->type == DEVICE_PATH_TYPE_END)
	79	return NULL;
	80	return (struct efi_device_path *)dp;
	81	}
	82
	83	/*
	84	* Compare two device-paths, stopping when the shorter of the two hits
	85	* an End* node. This is useful to, for example, compare a device-path
	86	* representing a device with one representing a file on the device, or
	87	* a device with a parent device.
	88	*/
ff401d3f HS	89	int efi_dp_match(const struct efi_device_path *a,
ff401d3f HS	90	const struct efi_device_path *b)
b66c60dd RC	91	{
	92	while (1) {
	93	int ret;
	94
	95	ret = memcmp(&a->length, &b->length, sizeof(a->length));
	96	if (ret)
	97	return ret;
	98
	99	ret = memcmp(a, b, a->length);
	100	if (ret)
	101	return ret;
	102
	103	a = efi_dp_next(a);
	104	b = efi_dp_next(b);
	105
	106	if (!a \|\| !b)
	107	return 0;
	108	}
	109	}
	110
	111
	112	/*
	113	* See UEFI spec (section 3.1.2, about short-form device-paths..
	114	* tl;dr: we can have a device-path that starts with a USB WWID
	115	* or USB Class node, and a few other cases which don't encode
	116	* the full device path with bus hierarchy:
	117	*
	118	* - MESSAGING:USB_WWID
	119	* - MESSAGING:USB_CLASS
	120	* - MEDIA:FILE_PATH
	121	* - MEDIA:HARD_DRIVE
	122	* - MESSAGING:URI
	123	*/
	124	static struct efi_device_path shorten_path(struct efi_device_path dp)
	125	{
	126	while (dp) {
	127	/*
	128	* TODO: Add MESSAGING:USB_WWID and MESSAGING:URI..
	129	* in practice fallback.efi just uses MEDIA:HARD_DRIVE
	130	* so not sure when we would see these other cases.
	131	*/
	132	if (EFI_DP_TYPE(dp, MESSAGING_DEVICE, MSG_USB_CLASS) \|\|
	133	EFI_DP_TYPE(dp, MEDIA_DEVICE, HARD_DRIVE_PATH) \|\|
	134	EFI_DP_TYPE(dp, MEDIA_DEVICE, FILE_PATH))
	135	return dp;
	136
	137	dp = efi_dp_next(dp);
	138	}
	139
	140	return dp;
	141	}
	142
	143	static struct efi_object find_obj(struct efi_device_path dp, bool short_path,
	144	struct efi_device_path **rem)
	145	{
	146	struct efi_object *efiobj;
905cb9e1	147	unsigned int dp_size = efi_dp_size(dp);
b66c60dd RC	148
b66c60dd RC	149	list_for_each_entry(efiobj, &efi_obj_list, link) {
72292aba HS	150	struct efi_handler *handler;
	151	struct efi_device_path *obj_dp;
	152	efi_status_t ret;
	153
	154	ret = efi_search_protocol(efiobj->handle,
	155	&efi_guid_device_path, &handler);
	156	if (ret != EFI_SUCCESS)
	157	continue;
	158	obj_dp = handler->protocol_interface;
	159
	160	do {
	161	if (efi_dp_match(dp, obj_dp) == 0) {
	162	if (rem) {
905cb9e1 AG	163	/*
	164	* Allow partial matches, but inform
	165	* the caller.
	166	*/
72292aba HS	167	rem = ((void )dp) +
72292aba HS	168	efi_dp_size(obj_dp);
905cb9e1 AG	169	return efiobj;
	170	} else {
	171	/* Only return on exact matches */
	172	if (efi_dp_size(obj_dp) == dp_size)
	173	return efiobj;
b66c60dd	174	}
72292aba	175	}
b66c60dd	176
72292aba HS	177	obj_dp = shorten_path(efi_dp_next(obj_dp));
72292aba HS	178	} while (short_path && obj_dp);
b66c60dd RC	179	}
	180
	181	return NULL;
	182	}
	183
	184
	185	/*
	186	* Find an efiobj from device-path, if 'rem' is not NULL, returns the
	187	* remaining part of the device path after the matched object.
	188	*/
	189	struct efi_object efi_dp_find_obj(struct efi_device_path dp,
	190	struct efi_device_path **rem)
	191	{
	192	struct efi_object *efiobj;
	193
905cb9e1 AG	194	/* Search for an exact match first */
905cb9e1 AG	195	efiobj = find_obj(dp, false, NULL);
b66c60dd	196
905cb9e1 AG	197	/* Then for a fuzzy match */
	198	if (!efiobj)
	199	efiobj = find_obj(dp, false, rem);
	200
	201	/* And now for a fuzzy short match */
b66c60dd RC	202	if (!efiobj)
	203	efiobj = find_obj(dp, true, rem);
	204
	205	return efiobj;
	206	}
	207
	208	/* return size not including End node: */
	209	unsigned efi_dp_size(const struct efi_device_path *dp)
	210	{
	211	unsigned sz = 0;
	212
	213	while (dp) {
	214	sz += dp->length;
	215	dp = efi_dp_next(dp);
	216	}
	217
	218	return sz;
	219	}
	220
	221	struct efi_device_path efi_dp_dup(const struct efi_device_path dp)
	222	{
	223	struct efi_device_path *ndp;
	224	unsigned sz = efi_dp_size(dp) + sizeof(END);
	225
	226	if (!dp)
	227	return NULL;
	228
	229	ndp = dp_alloc(sz);
	230	memcpy(ndp, dp, sz);
	231
	232	return ndp;
	233	}
	234
	235	struct efi_device_path efi_dp_append(const struct efi_device_path dp1,
	236	const struct efi_device_path *dp2)
	237	{
	238	struct efi_device_path *ret;
	239
	240	if (!dp1) {
	241	ret = efi_dp_dup(dp2);
	242	} else if (!dp2) {
	243	ret = efi_dp_dup(dp1);
	244	} else {
	245	/* both dp1 and dp2 are non-null */
	246	unsigned sz1 = efi_dp_size(dp1);
	247	unsigned sz2 = efi_dp_size(dp2);
	248	void *p = dp_alloc(sz1 + sz2 + sizeof(END));
	249	memcpy(p, dp1, sz1);
	250	memcpy(p + sz1, dp2, sz2);
	251	memcpy(p + sz1 + sz2, &END, sizeof(END));
	252	ret = p;
	253	}
	254
	255	return ret;
	256	}
	257
	258	struct efi_device_path efi_dp_append_node(const struct efi_device_path dp,
	259	const struct efi_device_path *node)
	260	{
	261	struct efi_device_path *ret;
	262
	263	if (!node && !dp) {
	264	ret = efi_dp_dup(&END);
	265	} else if (!node) {
266	ret = efi_dp_dup(dp);
267	} else if (!dp) {
268	unsigned sz = node->length;
269	void *p = dp_alloc(sz + sizeof(END));
270	memcpy(p, node, sz);
271	memcpy(p + sz, &END, sizeof(END));
272	ret = p;
273	} else {
274	/* both dp and node are non-null */
275	unsigned sz = efi_dp_size(dp);
276	void *p = dp_alloc(sz + node->length + sizeof(END));
277	memcpy(p, dp, sz);
278	memcpy(p + sz, node, node->length);
279	memcpy(p + sz + node->length, &END, sizeof(END));
280	ret = p;
281	}
282
283	return ret;
284	}
285
286	#ifdef CONFIG_DM
287	/* size of device-path not including END node for device and all parents
288	* up to the root device.
289	*/
290	static unsigned dp_size(struct udevice *dev)
291	{
292	if (!dev \|\| !dev->driver)
293	return sizeof(ROOT);
294
295	switch (dev->driver->id) {
296	case UCLASS_ROOT:
297	case UCLASS_SIMPLE_BUS:
298	/* stop traversing parents at this point: */
299	return sizeof(ROOT);
af3106a1 HS	300	#ifdef CONFIG_BLK
	301	case UCLASS_BLK:
	302	switch (dev->parent->uclass->uc_drv->id) {
	303	#ifdef CONFIG_IDE
	304	case UCLASS_IDE:
	305	return dp_size(dev->parent) +
	306	sizeof(struct efi_device_path_atapi);
	307	#endif
	308	#if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
	309	case UCLASS_SCSI:
	310	return dp_size(dev->parent) +
	311	sizeof(struct efi_device_path_scsi);
	312	#endif
	313	default:
	314	return dp_size(dev->parent);
	315	}
	316	#endif
b66c60dd RC	317	case UCLASS_MMC:
	318	return dp_size(dev->parent) +
	319	sizeof(struct efi_device_path_sd_mmc_path);
	320	case UCLASS_MASS_STORAGE:
	321	case UCLASS_USB_HUB:
	322	return dp_size(dev->parent) +
	323	sizeof(struct efi_device_path_usb_class);
	324	default:
	325	/* just skip over unknown classes: */
	326	return dp_size(dev->parent);
	327	}
	328	}
	329
af3106a1 HS	330	/*
	331	* Recursively build a device path.
	332	*
	333	* @buf pointer to the end of the device path
	334	* @dev device
	335	* @return pointer to the end of the device path
	336	*/
b66c60dd RC	337	static void dp_fill(void buf, struct udevice *dev)
	338	{
	339	if (!dev \|\| !dev->driver)
	340	return buf;
	341
	342	switch (dev->driver->id) {
	343	case UCLASS_ROOT:
	344	case UCLASS_SIMPLE_BUS: {
	345	/* stop traversing parents at this point: */
	346	struct efi_device_path_vendor *vdp = buf;
	347	*vdp = ROOT;
	348	return &vdp[1];
	349	}
af3106a1 HS	350	#ifdef CONFIG_BLK
	351	case UCLASS_BLK:
	352	switch (dev->parent->uclass->uc_drv->id) {
	353	#ifdef CONFIG_IDE
	354	case UCLASS_IDE: {
	355	struct efi_device_path_atapi *dp =
	356	dp_fill(buf, dev->parent);
	357	struct blk_desc *desc = dev_get_uclass_platdata(dev);
	358
	359	dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
	360	dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_ATAPI;
	361	dp->dp.length = sizeof(*dp);
	362	dp->logical_unit_number = desc->devnum;
	363	dp->primary_secondary = IDE_BUS(desc->devnum);
	364	dp->slave_master = desc->devnum %
	365	(CONFIG_SYS_IDE_MAXDEVICE /
	366	CONFIG_SYS_IDE_MAXBUS);
	367	return &dp[1];
	368	}
	369	#endif
	370	#if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
	371	case UCLASS_SCSI: {
	372	struct efi_device_path_scsi *dp =
	373	dp_fill(buf, dev->parent);
	374	struct blk_desc *desc = dev_get_uclass_platdata(dev);
	375
	376	dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
	377	dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_SCSI;
	378	dp->dp.length = sizeof(*dp);
	379	dp->logical_unit_number = desc->lun;
	380	dp->target_id = desc->target;
	381	return &dp[1];
	382	}
	383	#endif
	384	default:
	385	printf("unhandled parent class: %s (%u)\n",
	386	dev->name, dev->driver->id);
	387	return dp_fill(buf, dev->parent);
	388	}
	389	#endif
b66c60dd RC	390	#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
	391	case UCLASS_MMC: {
	392	struct efi_device_path_sd_mmc_path *sddp =
	393	dp_fill(buf, dev->parent);
	394	struct mmc *mmc = mmc_get_mmc_dev(dev);
	395	struct blk_desc *desc = mmc_get_blk_desc(mmc);
	396
	397	sddp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
66b051d5 HS	398	sddp->dp.sub_type = is_sd(desc) ?
	399	DEVICE_PATH_SUB_TYPE_MSG_SD :
	400	DEVICE_PATH_SUB_TYPE_MSG_MMC;
b66c60dd RC	401	sddp->dp.length = sizeof(*sddp);
	402	sddp->slot_number = dev->seq;
	403
	404	return &sddp[1];
	405	}
	406	#endif
	407	case UCLASS_MASS_STORAGE:
	408	case UCLASS_USB_HUB: {
	409	struct efi_device_path_usb_class *udp =
	410	dp_fill(buf, dev->parent);
	411	struct usb_device *udev = dev_get_parent_priv(dev);
	412	struct usb_device_descriptor *desc = &udev->descriptor;
	413
	414	udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
	415	udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS;
	416	udp->dp.length = sizeof(*udp);
	417	udp->vendor_id = desc->idVendor;
	418	udp->product_id = desc->idProduct;
	419	udp->device_class = desc->bDeviceClass;
	420	udp->device_subclass = desc->bDeviceSubClass;
	421	udp->device_protocol = desc->bDeviceProtocol;
	422
	423	return &udp[1];
	424	}
	425	default:
	426	debug("unhandled device class: %s (%u)\n",
	427	dev->name, dev->driver->id);
	428	return dp_fill(buf, dev->parent);
	429	}
	430	}
	431
	432	/* Construct a device-path from a device: */
	433	struct efi_device_path efi_dp_from_dev(struct udevice dev)
	434	{
	435	void buf, start;
	436
	437	start = buf = dp_alloc(dp_size(dev) + sizeof(END));
	438	buf = dp_fill(buf, dev);
	439	((struct efi_device_path )buf) = END;
	440
	441	return start;
	442	}
	443	#endif
	444
	445	static unsigned dp_part_size(struct blk_desc *desc, int part)
	446	{
	447	unsigned dpsize;
	448
	449	#ifdef CONFIG_BLK
2bc61b83 HS	450	{
	451	struct udevice *dev;
	452	int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
	453
	454	if (ret)
	455	dev = desc->bdev->parent;
	456	dpsize = dp_size(dev);
	457	}
b66c60dd RC	458	#else
	459	dpsize = sizeof(ROOT) + sizeof(struct efi_device_path_usb);
	460	#endif
	461
	462	if (part == 0) /* the actual disk, not a partition */
	463	return dpsize;
	464
	465	if (desc->part_type == PART_TYPE_ISO)
	466	dpsize += sizeof(struct efi_device_path_cdrom_path);
	467	else
	468	dpsize += sizeof(struct efi_device_path_hard_drive_path);
	469
	470	return dpsize;
	471	}
	472
bde6bfe4 HS	473	/*
	474	* Create a device path for a block device or one of its partitions.
	475	*
	476	* @buf buffer to which the device path is wirtten
	477	* @desc block device descriptor
	478	* @part partition number, 0 identifies a block device
	479	*/
b66c60dd RC	480	static void dp_part_fill(void buf, struct blk_desc *desc, int part)
	481	{
	482	disk_partition_t info;
	483
	484	#ifdef CONFIG_BLK
2bc61b83 HS	485	{
	486	struct udevice *dev;
	487	int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
	488
	489	if (ret)
	490	dev = desc->bdev->parent;
	491	buf = dp_fill(buf, dev);
	492	}
b66c60dd RC	493	#else
	494	/*
	495	* We could make a more accurate path, by looking at if_type
	496	* and handling all the different cases like we do for non-
	497	* legacy (ie CONFIG_BLK=y) case. But most important thing
	498	* is just to have a unique device-path for if_type+devnum.
bde6bfe4	499	* So map things to a fictitious USB device.
b66c60dd RC	500	*/
	501	struct efi_device_path_usb *udp;
	502
	503	memcpy(buf, &ROOT, sizeof(ROOT));
	504	buf += sizeof(ROOT);
	505
	506	udp = buf;
	507	udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
	508	udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB;
	509	udp->dp.length = sizeof(*udp);
	510	udp->parent_port_number = desc->if_type;
	511	udp->usb_interface = desc->devnum;
	512	buf = &udp[1];
	513	#endif
	514
	515	if (part == 0) /* the actual disk, not a partition */
	516	return buf;
	517
	518	part_get_info(desc, part, &info);
	519
	520	if (desc->part_type == PART_TYPE_ISO) {
	521	struct efi_device_path_cdrom_path *cddp = buf;
	522
7b982f00	523	cddp->boot_entry = part;
b66c60dd RC	524	cddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
	525	cddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CDROM_PATH;
	526	cddp->dp.length = sizeof(*cddp);
	527	cddp->partition_start = info.start;
	528	cddp->partition_end = info.size;
	529
	530	buf = &cddp[1];
	531	} else {
	532	struct efi_device_path_hard_drive_path *hddp = buf;
	533
	534	hddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
	535	hddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH;
	536	hddp->dp.length = sizeof(*hddp);
7b982f00	537	hddp->partition_number = part;
b66c60dd RC	538	hddp->partition_start = info.start;
	539	hddp->partition_end = info.size;
	540	if (desc->part_type == PART_TYPE_EFI)
	541	hddp->partmap_type = 2;
	542	else
	543	hddp->partmap_type = 1;
b6e9e097 JG	544
	545	switch (desc->sig_type) {
	546	case SIG_TYPE_NONE:
	547	default:
	548	hddp->signature_type = 0;
	549	memset(hddp->partition_signature, 0,
	550	sizeof(hddp->partition_signature));
	551	break;
	552	case SIG_TYPE_MBR:
	553	hddp->signature_type = 1;
	554	memset(hddp->partition_signature, 0,
	555	sizeof(hddp->partition_signature));
	556	memcpy(hddp->partition_signature, &desc->mbr_sig,
	557	sizeof(desc->mbr_sig));
	558	break;
	559	case SIG_TYPE_GUID:
	560	hddp->signature_type = 2;
b66c60dd RC	561	memcpy(hddp->partition_signature, &desc->guid_sig,
b66c60dd RC	562	sizeof(hddp->partition_signature));
b6e9e097 JG	563	break;
b6e9e097 JG	564	}
b66c60dd RC	565
	566	buf = &hddp[1];
	567	}
	568
	569	return buf;
	570	}
	571
	572
	573	/* Construct a device-path from a partition on a blk device: */
	574	struct efi_device_path efi_dp_from_part(struct blk_desc desc, int part)
	575	{
	576	void buf, start;
	577
	578	start = buf = dp_alloc(dp_part_size(desc, part) + sizeof(END));
	579
	580	buf = dp_part_fill(buf, desc, part);
	581
	582	((struct efi_device_path )buf) = END;
	583
	584	return start;
	585	}
	586
	587	/* convert path to an UEFI style path (ie. DOS style backslashes and utf16) */
	588	static void path_to_uefi(u16 uefi, const char path)
	589	{
	590	while (*path) {
	591	char c = *(path++);
	592	if (c == '/')
	593	c = '\\';
	594	*(uefi++) = c;
	595	}
	596	*uefi = '\0';
	597	}
	598
	599	/*
	600	* If desc is NULL, this creates a path with only the file component,
	601	* otherwise it creates a full path with both device and file components
	602	*/
	603	struct efi_device_path efi_dp_from_file(struct blk_desc desc, int part,
	604	const char *path)
	605	{
	606	struct efi_device_path_file_path *fp;
	607	void buf, start;
	608	unsigned dpsize = 0, fpsize;
	609
	610	if (desc)
	611	dpsize = dp_part_size(desc, part);
	612
	613	fpsize = sizeof(struct efi_device_path) + 2 * (strlen(path) + 1);
	614	dpsize += fpsize;
	615
	616	start = buf = dp_alloc(dpsize + sizeof(END));
	617
	618	if (desc)
	619	buf = dp_part_fill(buf, desc, part);
	620
	621	/* add file-path: */
	622	fp = buf;
	623	fp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
	624	fp->dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
	625	fp->dp.length = fpsize;
	626	path_to_uefi(fp->str, path);
	627	buf += fpsize;
	628
629	((struct efi_device_path )buf) = END;
630
631	return start;
632	}
633
634	#ifdef CONFIG_NET
635	struct efi_device_path *efi_dp_from_eth(void)
636	{
637	struct efi_device_path_mac_addr *ndp;
638	void buf, start;
639	unsigned dpsize = 0;
640
641	assert(eth_get_dev());
642
643	#ifdef CONFIG_DM_ETH
644	dpsize += dp_size(eth_get_dev());
645	#else
646	dpsize += sizeof(ROOT);
647	#endif
648	dpsize += sizeof(*ndp);
649
650	start = buf = dp_alloc(dpsize + sizeof(END));
651
652	#ifdef CONFIG_DM_ETH
653	buf = dp_fill(buf, eth_get_dev());
654	#else
655	memcpy(buf, &ROOT, sizeof(ROOT));
656	buf += sizeof(ROOT);
657	#endif
658
659	ndp = buf;
660	ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
661	ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
662	ndp->dp.length = sizeof(*ndp);
663	memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
664	buf = &ndp[1];
665
666	((struct efi_device_path )buf) = END;
667
668	return start;
669	}
670	#endif
671
bf19273e RC	672	/* Construct a device-path for memory-mapped image */
	673	struct efi_device_path *efi_dp_from_mem(uint32_t memory_type,
	674	uint64_t start_address,
	675	uint64_t end_address)
	676	{
	677	struct efi_device_path_memory *mdp;
	678	void buf, start;
	679
	680	start = buf = dp_alloc(sizeof(*mdp) + sizeof(END));
	681
	682	mdp = buf;
	683	mdp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
	684	mdp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MEMORY;
	685	mdp->dp.length = sizeof(*mdp);
	686	mdp->memory_type = memory_type;
	687	mdp->start_address = start_address;
	688	mdp->end_address = end_address;
	689	buf = &mdp[1];
	690
	691	((struct efi_device_path )buf) = END;
	692
	693	return start;
	694	}
	695
b66c60dd RC	696	/*
	697	* Helper to split a full device path (containing both device and file
	698	* parts) into it's constituent parts.
	699	*/
	700	void efi_dp_split_file_path(struct efi_device_path *full_path,
	701	struct efi_device_path **device_path,
	702	struct efi_device_path **file_path)
	703	{
	704	struct efi_device_path p, dp, *fp;
	705
	706	dp = efi_dp_dup(full_path);
	707	p = dp;
	708	while (!EFI_DP_TYPE(p, MEDIA_DEVICE, FILE_PATH))
	709	p = efi_dp_next(p);
	710	fp = efi_dp_dup(p);
	711
	712	p->type = DEVICE_PATH_TYPE_END;
	713	p->sub_type = DEVICE_PATH_SUB_TYPE_END;
	714	p->length = sizeof(*p);
	715
	716	*device_path = dp;
	717	*file_path = fp;
	718	}