1 files changed, 210 insertions, 0 deletions
diff --git a/lib/efi_driver/efi_block_device.c b/lib/efi_driver/efi_block_device.c
new file mode 100644
index 0000000000..d9d2b14f61
--- /dev/null
+++ b/lib/efi_driver/efi_block_device.c
@@ -0,0 +1,210 @@
+/*
+ *  EFI block driver
+ *
+ *  Copyright (c) 2017 Heinrich Schuchardt
+ *
+ *  SPDX-License-Identifier:     GPL-2.0+
+ *
+ * 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 <efi_driver.h>
+#include <dm/device-internal.h>
+#include <dm/root.h>
+
+/*
+ * EFI attributes of the udevice handled by this driver.
+ *
+ * handle	handle of the controller on which this driver is installed
+ * io		block io protocol proxied by this driver
+ */
+struct efi_blk_priv {
+	efi_handle_t		handle;
+	struct efi_block_io	*io;
+};
+
+/*
+ * 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_priv *priv = dev->priv;
+	struct efi_block_io *io = priv->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;
+}
+
+/*
+ * 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_priv *priv = dev->priv;
+	struct efi_block_io *io = priv->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;
+}
+
+/*
+ * Create partions for the block device.
+ *
+ * @handle	EFI handle of the block device
+ * @dev		udevice of the block device
+ */
+static int efi_bl_bind_partitions(efi_handle_t handle, struct udevice *dev)
+{
+	struct blk_desc *desc;
+	const char *if_typename;
+
+	desc = dev_get_uclass_platdata(dev);
+	if_typename = blk_get_if_type_name(desc->if_type);
+
+	return efi_disk_create_partitions(handle, desc, if_typename,
+					  desc->devnum, dev->name);
+}
+
+/*
+ * Create a block device for a handle
+ *
+ * @handle	handle
+ * @interface	block io protocol
+ * @return	0 = success
+ */
+static int efi_bl_bind(efi_handle_t handle, void *interface)
+{
+	struct udevice *bdev, *parent = dm_root();
+	int ret, devnum;
+	char *name;
+	struct efi_object *obj = efi_search_obj(handle);
+	struct efi_block_io *io = interface;
+	int disks;
+	struct efi_blk_priv *priv;
+
+	EFI_PRINT("%s: handle %p, interface %p\n", __func__, handle, io);
+
+	if (!obj)
+		return -ENOENT;
+
+	devnum = blk_find_max_devnum(IF_TYPE_EFI);
+	if (devnum == -ENODEV)
+		devnum = 0;
+	else if (devnum < 0)
+		return devnum;
+
+	name = calloc(1, 18); /* strlen("efiblk#2147483648") + 1 */
+	if (!name)
+		return -ENOMEM;
+	sprintf(name, "efiblk#%d", devnum);
+
+	/* Create driver model udevice for the EFI block io device */
+	ret = blk_create_device(parent, "efi_blk", name, IF_TYPE_EFI, devnum,
+				io->media->block_size,
+				(lbaint_t)io->media->last_block, &bdev);
+	if (ret)
+		return ret;
+	if (!bdev)
+		return -ENOENT;
+	/* Allocate priv */
+	ret = device_probe(bdev);
+	if (ret)
+		return ret;
+	EFI_PRINT("%s: block device '%s' created\n", __func__, bdev->name);
+
+	priv = bdev->priv;
+	priv->handle = handle;
+	priv->io = interface;
+
+	ret = blk_prepare_device(bdev);
+
+	/* Create handles for the partions of the block device */
+	disks = efi_bl_bind_partitions(handle, bdev);
+	EFI_PRINT("Found %d partitions\n", disks);
+
+	return 0;
+}
+
+/* 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,
+	.priv_auto_alloc_size	= sizeof(struct efi_blk_priv),
+};
+
+/* EFI driver operators */
+static const struct efi_driver_ops driver_ops = {
+	.protocol	= &efi_block_io_guid,
+	.child_protocol = &efi_block_io_guid,
+	.bind		= efi_bl_bind,
+};
+
+/* Identify as EFI driver */
+U_BOOT_DRIVER(efi_block) = {
+	.name		= "EFI block driver",
+	.id		= UCLASS_EFI,
+	.ops		= &driver_ops,
+};