| Simon Glass | d8063dc | 2021-12-04 08:56:32 -0700 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
| 2 | /* |
| 3 | * Block driver for EFI devices |
| 4 | * This supports a media driver of UCLASS_EFI with a child UCLASS_BLK |
| 5 | * It allows block-level access to EFI devices made available via EFI boot |
| 6 | * services |
| 7 | * |
| 8 | * Copyright 2021 Google LLC |
| 9 | */ |
| 10 | |
| 11 | #include <common.h> |
| 12 | #include <blk.h> |
| 13 | #include <dm.h> |
| 14 | #include <efi.h> |
| 15 | #include <efi_api.h> |
| 16 | |
| 17 | struct efi_block_plat { |
| 18 | struct efi_block_io *blkio; |
| 19 | }; |
| 20 | |
| 21 | /** |
| 22 | * Read from block device |
| 23 | * |
| 24 | * @dev: device |
| 25 | * @blknr: first block to be read |
| 26 | * @blkcnt: number of blocks to read |
| 27 | * @buffer: output buffer |
| 28 | * Return: number of blocks transferred |
| 29 | */ |
| 30 | static ulong efi_bl_read(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, |
| 31 | void *buffer) |
| 32 | { |
| 33 | struct efi_block_plat *plat = dev_get_plat(dev); |
| 34 | struct efi_block_io *io = plat->blkio; |
| 35 | efi_status_t ret; |
| 36 | |
| 37 | log_debug("read buf=%p, block=%lx, count=%lx: ", buffer, (ulong)blknr, |
| 38 | (ulong)blkcnt); |
| 39 | ret = io->read_blocks(io, io->media->media_id, blknr, |
| 40 | blkcnt * io->media->block_size, buffer); |
| 41 | log_debug("ret=%lx (dec %ld)\n", ret & ~EFI_ERROR_MASK, |
| 42 | ret & ~EFI_ERROR_MASK); |
| 43 | if (ret) |
| 44 | return 0; |
| 45 | |
| 46 | return blkcnt; |
| 47 | } |
| 48 | |
| 49 | /** |
| 50 | * Write to block device |
| 51 | * |
| 52 | * @dev: device |
| 53 | * @blknr: first block to be write |
| 54 | * @blkcnt: number of blocks to write |
| 55 | * @buffer: input buffer |
| 56 | * Return: number of blocks transferred |
| 57 | */ |
| 58 | static ulong efi_bl_write(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, |
| 59 | const void *buffer) |
| 60 | { |
| 61 | struct efi_block_plat *plat = dev_get_plat(dev); |
| 62 | struct efi_block_io *io = plat->blkio; |
| 63 | efi_status_t ret; |
| 64 | |
| 65 | log_debug("write buf=%p, block=%lx, count=%lx: ", buffer, (ulong)blknr, |
| 66 | (ulong)blkcnt); |
| 67 | ret = io->write_blocks(io, io->media->media_id, blknr, |
| 68 | blkcnt * io->media->block_size, (void *)buffer); |
| 69 | log_debug("ret=%lx (dec %ld)\n", ret & ~EFI_ERROR_MASK, |
| 70 | ret & ~EFI_ERROR_MASK); |
| 71 | if (ret) |
| 72 | return 0; |
| 73 | |
| 74 | return blkcnt; |
| 75 | } |
| 76 | |
| 77 | /* Block device driver operators */ |
| 78 | static const struct blk_ops efi_blk_ops = { |
| 79 | .read = efi_bl_read, |
| 80 | .write = efi_bl_write, |
| 81 | }; |
| 82 | |
| 83 | U_BOOT_DRIVER(efi_block) = { |
| 84 | .name = "efi_block", |
| 85 | .id = UCLASS_BLK, |
| 86 | .ops = &efi_blk_ops, |
| 87 | .plat_auto = sizeof(struct efi_block_plat), |
| 88 | }; |
| 89 | |
| 90 | static int efi_media_bind(struct udevice *dev) |
| 91 | { |
| 92 | struct efi_media_plat *plat = dev_get_plat(dev); |
| 93 | struct efi_block_plat *blk_plat; |
| 94 | struct udevice *blk; |
| 95 | int ret; |
| 96 | |
| 97 | ret = blk_create_devicef(dev, "efi_block", "blk", IF_TYPE_EFI_MEDIA, |
| 98 | dev_seq(dev), plat->blkio->media->block_size, |
| 99 | plat->blkio->media->last_block, &blk); |
| 100 | if (ret) { |
| 101 | debug("Cannot create block device\n"); |
| 102 | return ret; |
| 103 | } |
| 104 | blk_plat = dev_get_plat(blk); |
| 105 | blk_plat->blkio = plat->blkio; |
| 106 | |
| 107 | return 0; |
| 108 | } |
| 109 | |
| 110 | U_BOOT_DRIVER(efi_media) = { |
| 111 | .name = "efi_media", |
| 112 | .id = UCLASS_EFI_MEDIA, |
| 113 | .bind = efi_media_bind, |
| 114 | .plat_auto = sizeof(struct efi_media_plat), |
| 115 | }; |