Add a block driver which handles read/write for EFI block devices. This driver actually already exists ('efi_block') but is not really suitable for use as a real U-Boot driver:
- The operations do not provide a udevice - The code is designed for running as part of EFI loader, so uses EFI_PRINT() and EFI_CALL(). - The bind method probes the device, which is not permitted - It uses 'EFI' as its parent device
The new driver is more 'normal', just requiring its platform data be set up in advance.
Signed-off-by: Simon Glass sjg@chromium.org ---
(no changes since v2)
Changes in v2: - Drop mention of partitions from the commit message
drivers/block/Kconfig | 10 ++++ drivers/block/Makefile | 1 + drivers/block/efi_blk.c | 115 ++++++++++++++++++++++++++++++++++++++++ include/efi.h | 11 ++++ 4 files changed, 137 insertions(+) create mode 100644 drivers/block/efi_blk.c
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index 755fdccb574..8235430497d 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -82,6 +82,16 @@ config EFI_MEDIA_SANDBOX EFI_MEDIA uclass. It does not do anything useful, since sandbox does not actually support running on top of UEFI.
+config EFI_MEDIA_BLK + bool "EFI media block driver" + depends on EFI_APP + default y + help + Enables a block driver for providing access to UEFI devices. This + allows use of block devices detected by the underlying UEFI + implementation. With this it is possible to use filesystems on these + devices, for example. + endif # EFI_MEDIA
config IDE diff --git a/drivers/block/Makefile b/drivers/block/Makefile index 3778633da1d..b221a7c6eea 100644 --- a/drivers/block/Makefile +++ b/drivers/block/Makefile @@ -17,3 +17,4 @@ obj-$(CONFIG_$(SPL_TPL_)BLOCK_CACHE) += blkcache.o
obj-$(CONFIG_EFI_MEDIA) += efi-media-uclass.o obj-$(CONFIG_EFI_MEDIA_SANDBOX) += sb_efi_media.o +obj-$(CONFIG_EFI_MEDIA_BLK) += efi_blk.o diff --git a/drivers/block/efi_blk.c b/drivers/block/efi_blk.c new file mode 100644 index 00000000000..c00b0cc0b1c --- /dev/null +++ b/drivers/block/efi_blk.c @@ -0,0 +1,115 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Block driver for EFI devices + * This supports a media driver of UCLASS_EFI with a child UCLASS_BLK + * It allows block-level access to EFI devices made available via EFI boot + * services + * + * Copyright 2021 Google LLC + */ + +#include <common.h> +#include <blk.h> +#include <dm.h> +#include <efi.h> +#include <efi_api.h> + +struct efi_block_plat { + struct efi_block_io *blkio; +}; + +/** + * Read from block device + * + * @dev: device + * @blknr: first block to be read + * @blkcnt: number of blocks to read + * @buffer: output buffer + * Return: number of blocks transferred + */ +static ulong efi_bl_read(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, + void *buffer) +{ + struct efi_block_plat *plat = dev_get_plat(dev); + struct efi_block_io *io = plat->blkio; + efi_status_t ret; + + log_debug("read buf=%p, block=%lx, count=%lx: ", buffer, (ulong)blknr, + (ulong)blkcnt); + ret = io->read_blocks(io, io->media->media_id, blknr, + blkcnt * io->media->block_size, buffer); + log_debug("ret=%lx (dec %ld)\n", ret & ~EFI_ERROR_MASK, + ret & ~EFI_ERROR_MASK); + if (ret) + return 0; + + return blkcnt; +} + +/** + * Write to block device + * + * @dev: device + * @blknr: first block to be write + * @blkcnt: number of blocks to write + * @buffer: input buffer + * Return: number of blocks transferred + */ +static ulong efi_bl_write(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, + const void *buffer) +{ + struct efi_block_plat *plat = dev_get_plat(dev); + struct efi_block_io *io = plat->blkio; + efi_status_t ret; + + log_debug("write buf=%p, block=%lx, count=%lx: ", buffer, (ulong)blknr, + (ulong)blkcnt); + ret = io->write_blocks(io, io->media->media_id, blknr, + blkcnt * io->media->block_size, (void *)buffer); + log_debug("ret=%lx (dec %ld)\n", ret & ~EFI_ERROR_MASK, + ret & ~EFI_ERROR_MASK); + if (ret) + return 0; + + return blkcnt; +} + +/* Block device driver operators */ +static const struct blk_ops efi_blk_ops = { + .read = efi_bl_read, + .write = efi_bl_write, +}; + +U_BOOT_DRIVER(efi_block) = { + .name = "efi_block", + .id = UCLASS_BLK, + .ops = &efi_blk_ops, + .plat_auto = sizeof(struct efi_block_plat), +}; + +static int efi_media_bind(struct udevice *dev) +{ + struct efi_media_plat *plat = dev_get_plat(dev); + struct efi_block_plat *blk_plat; + struct udevice *blk; + int ret; + + ret = blk_create_devicef(dev, "efi_block", "blk", IF_TYPE_EFI, + dev_seq(dev), plat->blkio->media->block_size, + plat->blkio->media->last_block, &blk); + if (ret) { + debug("Cannot create block device\n"); + return ret; + } + blk_plat = dev_get_plat(blk); + blk_plat->blkio = plat->blkio; + + return 0; +} + +U_BOOT_DRIVER(efi_media) = { + .name = "efi_media", + .id = UCLASS_EFI_MEDIA, + .bind = efi_media_bind, + .plat_auto = sizeof(struct efi_media_plat), +}; diff --git a/include/efi.h b/include/efi.h index b5835422b95..0ec5913ddd1 100644 --- a/include/efi.h +++ b/include/efi.h @@ -414,6 +414,17 @@ struct efi_priv { void *next_hdr; };
+/* + * EFI attributes of the udevice handled by efi_media driver + * + * @handle: handle of the controller on which this driver is installed + * @blkio: block io protocol proxied by this driver + */ +struct efi_media_plat { + efi_handle_t handle; + struct efi_block_io *blkio; +}; + /* Base address of the EFI image */ extern char image_base[];