blob: 34a0365739d7f17fd72656d7e5eddb2e7b121bc2 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* EFI block driver
*
* Copyright (c) 2017 Heinrich Schuchardt
*
* The EFI uclass creates a handle for this driver and installs the
* driver binding protocol on it.
*
* The EFI block driver binds to controllers implementing the block io
* protocol.
*
* When the bind function of the EFI block driver is called it creates a
* new U-Boot block device. It installs child handles for all partitions and
* installs the simple file protocol on these.
*
* The read and write functions of the EFI block driver delegate calls to the
* controller that it is bound to.
*
* A usage example is as following:
*
* U-Boot loads the iPXE snp.efi executable. iPXE connects an iSCSI drive and
* exposes a handle with the block IO protocol. It calls ConnectController.
*
* Now the EFI block driver installs the partitions with the simple file
* protocol.
*
* iPXE uses the simple file protocol to load Grub or the Linux Kernel.
*/
#include <blk.h>
#include <dm.h>
#include <efi_driver.h>
#include <malloc.h>
#include <dm/device-internal.h>
#include <dm/root.h>
#include <dm/tag.h>
/**
* struct efi_blk_plat - attributes of a block device
*
* @handle: handle of the controller on which this driver is installed
* @io: block io protocol proxied by this driver
*/
struct efi_blk_plat {
efi_handle_t handle;
struct efi_block_io *io;
};
/**
* efi_bl_read() - 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_blk_plat *plat = dev_get_plat(dev);
struct efi_block_io *io = plat->io;
efi_status_t ret;
EFI_PRINT("%s: read '%s', from block " LBAFU ", " LBAFU " blocks\n",
__func__, dev->name, blknr, blkcnt);
ret = EFI_CALL(io->read_blocks(
io, io->media->media_id, (u64)blknr,
(efi_uintn_t)blkcnt *
(efi_uintn_t)io->media->block_size, buffer));
EFI_PRINT("%s: r = %u\n", __func__,
(unsigned int)(ret & ~EFI_ERROR_MASK));
if (ret != EFI_SUCCESS)
return 0;
return blkcnt;
}
/**
* efi_bl_write() - 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_blk_plat *plat = dev_get_plat(dev);
struct efi_block_io *io = plat->io;
efi_status_t ret;
EFI_PRINT("%s: write '%s', from block " LBAFU ", " LBAFU " blocks\n",
__func__, dev->name, blknr, blkcnt);
ret = EFI_CALL(io->write_blocks(
io, io->media->media_id, (u64)blknr,
(efi_uintn_t)blkcnt *
(efi_uintn_t)io->media->block_size,
(void *)buffer));
EFI_PRINT("%s: r = %u\n", __func__,
(unsigned int)(ret & ~EFI_ERROR_MASK));
if (ret != EFI_SUCCESS)
return 0;
return blkcnt;
}
/**
* efi_bl_create_block_device() - create a block device for a handle
*
* @handle: handle
* @interface: block io protocol
* Return: status code
*/
static efi_status_t
efi_bl_create_block_device(efi_handle_t handle, void *interface)
{
struct udevice *bdev = NULL, *parent = dm_root();
efi_status_t ret;
int devnum;
char *name;
struct efi_block_io *io = interface;
struct efi_blk_plat *plat;
devnum = blk_next_free_devnum(UCLASS_EFI_LOADER);
if (devnum < 0)
return EFI_OUT_OF_RESOURCES;
name = calloc(1, 18); /* strlen("efiblk#2147483648") + 1 */
if (!name)
return EFI_OUT_OF_RESOURCES;
sprintf(name, "efiblk#%d", devnum);
/* Create driver model udevice for the EFI block io device */
if (blk_create_device(parent, "efi_blk", name, UCLASS_EFI_LOADER,
devnum, io->media->block_size,
(lbaint_t)io->media->last_block, &bdev)) {
ret = EFI_OUT_OF_RESOURCES;
free(name);
goto err;
}
/* Set the DM_FLAG_NAME_ALLOCED flag to avoid a memory leak */
device_set_name_alloced(bdev);
plat = dev_get_plat(bdev);
plat->handle = handle;
plat->io = interface;
if (efi_link_dev(handle, bdev)) {
ret = EFI_OUT_OF_RESOURCES;
goto err;
}
if (device_probe(bdev)) {
ret = EFI_DEVICE_ERROR;
goto err;
}
EFI_PRINT("%s: block device '%s' created\n", __func__, bdev->name);
return EFI_SUCCESS;
err:
efi_unlink_dev(handle);
if (bdev)
device_unbind(bdev);
return ret;
}
/**
* efi_bl_bind() - bind to a block io protocol
*
* @this: driver binding protocol
* @handle: handle
* @interface: block io protocol
* Return: status code
*/
static efi_status_t efi_bl_bind(
struct efi_driver_binding_extended_protocol *this,
efi_handle_t handle, void *interface)
{
efi_status_t ret = EFI_SUCCESS;
struct efi_object *obj = efi_search_obj(handle);
EFI_PRINT("%s: handle %p, interface %p\n", __func__, handle, interface);
if (!obj || !interface)
return EFI_INVALID_PARAMETER;
if (!handle->dev)
ret = efi_bl_create_block_device(handle, interface);
return ret;
}
/**
* efi_bl_init() - initialize block device driver
*
* @this: extended driver binding protocol
*/
static efi_status_t
efi_bl_init(struct efi_driver_binding_extended_protocol *this)
{
int ret;
ret = event_register("efi_disk add", EVT_DM_POST_PROBE,
efi_disk_probe, this);
if (ret) {
log_err("Event registration for efi_disk add failed\n");
return EFI_OUT_OF_RESOURCES;
}
ret = event_register("efi_disk del", EVT_DM_PRE_REMOVE,
efi_disk_remove, this);
if (ret) {
log_err("Event registration for efi_disk del failed\n");
return EFI_OUT_OF_RESOURCES;
}
return EFI_SUCCESS;
}
/* Block device driver operators */
static const struct blk_ops efi_blk_ops = {
.read = efi_bl_read,
.write = efi_bl_write,
};
/* Identify as block device driver */
U_BOOT_DRIVER(efi_blk) = {
.name = "efi_blk",
.id = UCLASS_BLK,
.ops = &efi_blk_ops,
.plat_auto = sizeof(struct efi_blk_plat),
};
/* EFI driver operators */
static const struct efi_driver_ops driver_ops = {
.protocol = &efi_block_io_guid,
.child_protocol = &efi_block_io_guid,
.init = efi_bl_init,
.bind = efi_bl_bind,
};
/* Identify as EFI driver */
U_BOOT_DRIVER(efi_block) = {
.name = "EFI block driver",
.id = UCLASS_EFI_LOADER,
.ops = &driver_ops,
};