1 // SPDX-License-Identifier: GPL-2.0+
5 * Copyright (c) 2017 Heinrich Schuchardt
7 * The EFI uclass creates a handle for this driver and installs the
8 * driver binding protocol on it.
10 * The EFI block driver binds to controllers implementing the block io
13 * When the bind function of the EFI block driver is called it creates a
14 * new U-Boot block device. It installs child handles for all partitions and
15 * installs the simple file protocol on these.
17 * The read and write functions of the EFI block driver delegate calls to the
18 * controller that it is bound to.
20 * A usage example is as following:
22 * U-Boot loads the iPXE snp.efi executable. iPXE connects an iSCSI drive and
23 * exposes a handle with the block IO protocol. It calls ConnectController.
25 * Now the EFI block driver installs the partitions with the simple file
28 * iPXE uses the simple file protocol to load Grub or the Linux Kernel.
34 #include <efi_driver.h>
36 #include <dm/device-internal.h>
40 * EFI attributes of the udevice handled by this driver.
42 * handle handle of the controller on which this driver is installed
43 * io block io protocol proxied by this driver
47 struct efi_block_io *io;
51 * Read from block device
54 * @blknr: first block to be read
55 * @blkcnt: number of blocks to read
56 * @buffer: output buffer
57 * Return: number of blocks transferred
59 static ulong efi_bl_read(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt,
62 struct efi_blk_plat *plat = dev_get_plat(dev);
63 struct efi_block_io *io = plat->io;
66 EFI_PRINT("%s: read '%s', from block " LBAFU ", " LBAFU " blocks\n",
67 __func__, dev->name, blknr, blkcnt);
68 ret = EFI_CALL(io->read_blocks(
69 io, io->media->media_id, (u64)blknr,
71 (efi_uintn_t)io->media->block_size, buffer));
72 EFI_PRINT("%s: r = %u\n", __func__,
73 (unsigned int)(ret & ~EFI_ERROR_MASK));
74 if (ret != EFI_SUCCESS)
80 * Write to block device
83 * @blknr: first block to be write
84 * @blkcnt: number of blocks to write
85 * @buffer: input buffer
86 * Return: number of blocks transferred
88 static ulong efi_bl_write(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt,
91 struct efi_blk_plat *plat = dev_get_plat(dev);
92 struct efi_block_io *io = plat->io;
95 EFI_PRINT("%s: write '%s', from block " LBAFU ", " LBAFU " blocks\n",
96 __func__, dev->name, blknr, blkcnt);
97 ret = EFI_CALL(io->write_blocks(
98 io, io->media->media_id, (u64)blknr,
100 (efi_uintn_t)io->media->block_size,
102 EFI_PRINT("%s: r = %u\n", __func__,
103 (unsigned int)(ret & ~EFI_ERROR_MASK));
104 if (ret != EFI_SUCCESS)
110 * Create partions for the block device.
112 * @handle: EFI handle of the block device
113 * @dev: udevice of the block device
114 * Return: number of partitions created
116 static int efi_bl_bind_partitions(efi_handle_t handle, struct udevice *dev)
118 struct blk_desc *desc;
119 const char *if_typename;
121 desc = dev_get_uclass_plat(dev);
122 if_typename = blk_get_if_type_name(desc->if_type);
124 return efi_disk_create_partitions(handle, desc, if_typename,
125 desc->devnum, dev->name);
129 * Create a block device for a handle
132 * @interface: block io protocol
133 * Return: 0 = success
135 static int efi_bl_bind(efi_handle_t handle, void *interface)
137 struct udevice *bdev, *parent = dm_root();
140 struct efi_object *obj = efi_search_obj(handle);
141 struct efi_block_io *io = interface;
143 struct efi_blk_plat *plat;
145 EFI_PRINT("%s: handle %p, interface %p\n", __func__, handle, io);
150 devnum = blk_find_max_devnum(IF_TYPE_EFI);
151 if (devnum == -ENODEV)
156 name = calloc(1, 18); /* strlen("efiblk#2147483648") + 1 */
159 sprintf(name, "efiblk#%d", devnum);
161 /* Create driver model udevice for the EFI block io device */
162 ret = blk_create_device(parent, "efi_blk", name, IF_TYPE_EFI, devnum,
163 io->media->block_size,
164 (lbaint_t)io->media->last_block, &bdev);
169 /* Set the DM_FLAG_NAME_ALLOCED flag to avoid a memory leak */
170 device_set_name_alloced(bdev);
172 plat = dev_get_plat(bdev);
173 plat->handle = handle;
174 plat->io = interface;
176 ret = device_probe(bdev);
179 EFI_PRINT("%s: block device '%s' created\n", __func__, bdev->name);
181 /* Create handles for the partions of the block device */
182 disks = efi_bl_bind_partitions(handle, bdev);
183 EFI_PRINT("Found %d partitions\n", disks);
188 /* Block device driver operators */
189 static const struct blk_ops efi_blk_ops = {
191 .write = efi_bl_write,
194 /* Identify as block device driver */
195 U_BOOT_DRIVER(efi_blk) = {
199 .plat_auto = sizeof(struct efi_blk_plat),
202 /* EFI driver operators */
203 static const struct efi_driver_ops driver_ops = {
204 .protocol = &efi_block_io_guid,
205 .child_protocol = &efi_block_io_guid,
209 /* Identify as EFI driver */
210 U_BOOT_DRIVER(efi_block) = {
211 .name = "EFI block driver",