1 files changed, 137 insertions, 0 deletions
diff --git a/boot/vbe_common.h b/boot/vbe_common.h
new file mode 100644
index 00000000000..84117815a19
--- /dev/null
+++ b/boot/vbe_common.h
@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Verified Boot for Embedded (VBE) common functions
+ *
+ * Copyright 2024 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#ifndef __VBE_COMMON_H
+#define __VBE_COMMON_H
+
+#include <linux/types.h>
+
+struct spl_image_info;
+struct udevice;
+
+/*
+ * Controls whether we use a full bootmeth driver with VBE in this phase, or
+ * just access the information directly.
+ *
+ * For now VBE-simple uses the full bootmeth, but VBE-abrec does not, to reduce
+ * code size
+ */
+#define USE_BOOTMETH	CONFIG_IS_ENABLED(BOOTMETH_VBE_SIMPLE)
+
+enum {
+	MAX_VERSION_LEN		= 256,
+
+	NVD_HDR_VER_SHIFT	= 0,
+	NVD_HDR_VER_MASK	= 0xf,
+	NVD_HDR_SIZE_SHIFT	= 4,
+	NVD_HDR_SIZE_MASK	= 0xf << NVD_HDR_SIZE_SHIFT,
+
+	/* Firmware key-version is in the top 16 bits of fw_ver */
+	FWVER_KEY_SHIFT		= 16,
+	FWVER_FW_MASK		= 0xffff,
+
+	NVD_HDR_VER_CUR		= 1,	/* current version */
+};
+
+/**
+ * struct vbe_nvdata - basic storage format for non-volatile data
+ *
+ * This is used for all VBE methods
+ *
+ * @crc8: crc8 for the entire record except @crc8 field itself
+ * @hdr: header size and version (NVD_HDR_...)
+ * @spare1: unused, must be 0
+ * @fw_vernum: version and key version (FWVER_...)
+ * @flags: Flags controlling operation (enum vbe_flags)
+ */
+struct vbe_nvdata {
+	u8 crc8;
+	u8 hdr;
+	u16 spare1;
+	u32 fw_vernum;
+	u32 flags;
+	u8 spare2[0x34];
+};
+
+/**
+ * vbe_get_blk() - Obtain the block device to use for VBE
+ *
+ * Decodes the string to produce a block device
+ *
+ * @storage: String indicating the device to use, e.g. "mmc1"
+ * @blkp: Returns associated block device, on success
+ * Return 0 if OK, -ENODEV if @storage does not end with a number, -E2BIG if
+ * the device name is more than 15 characters, -ENXIO if the block device could
+ * not be found
+ */
+int vbe_get_blk(const char *storage, struct udevice **blkp);
+
+/**
+ * vbe_read_version() - Read version-string from a block device
+ *
+ * Reads the VBE version-string from a device. This function reads a single
+ * block from the device, so the string cannot be larger than that. It uses a
+ * temporary buffer for the read, then copies in up to @size bytes
+ *
+ * @blk: Device to read from
+ * @offset: Offset to read, in bytes
+ * @version: Place to put the string
+ * @max_size: Maximum size of @version
+ * Return: 0 if OK, -E2BIG if @max_size > block size, -EBADF if the offset is
+ * not block-aligned, -EIO if an I/O error occurred
+ */
+int vbe_read_version(struct udevice *blk, ulong offset, char *version,
+		     int max_size);
+
+/**
+ * vbe_read_nvdata() - Read non-volatile data from a block device
+ *
+ * Reads the VBE nvdata from a device. This function reads a single block from
+ * the device, so the nvdata cannot be larger than that.
+ *
+ * @blk: Device to read from
+ * @offset: Offset to read, in bytes
+ * @size: Number of bytes to read
+ * @buf: Buffer to hold the data
+ * Return: 0 if OK, -E2BIG if @size > block size, -EBADF if the offset is not
+ * block-aligned, -EIO if an I/O error occurred, -EPERM if the header version is
+ * incorrect, the header size is invalid or the data fails its CRC check
+ */
+int vbe_read_nvdata(struct udevice *blk, ulong offset, ulong size, u8 *buf);
+
+/**
+ * vbe_read_fit() - Read an image from a FIT
+ *
+ * This handles most of the VBE logic for reading from a FIT. It reads the FIT
+ * metadata, decides which image to load and loads it to a suitable address,
+ * ready for jumping to the next phase of VBE.
+ *
+ * This supports transition from VPL to SPL as well as SPL to U-Boot proper. For
+ * now, TPL->VPL is not supported.
+ *
+ * Both embedded and external data are supported for the FIT
+ *
+ * @blk: Block device containing FIT
+ * @area_offset: Byte offset of the VBE area in @blk containing the FIT
+ * @area_size: Size of the VBE area
+ * @image: SPL image to fill in with details of the loaded image, or NULL
+ * @load_addrp: If non-null, returns the address where the image was loaded
+ * @lenp: If non-null, returns the size of the image loaded, in bytes
+ * @namep: If non-null, returns the name of the FIT-image node that was loaded
+ *	(allocated by this function)
+ * Return: 0 if OK, -EINVAL if the area does not contain an FDT (the underlying
+ * format for FIT), -E2BIG if the FIT extends past @area_size, -ENOMEM if there
+ * was not space to allocate the image-node name, other error if a read error
+ * occurred (see blk_read()), or something went wrong with the actually
+ * FIT-parsing (see fit_image_load()).
+ */
+int vbe_read_fit(struct udevice *blk, ulong area_offset, ulong area_size,
+		 struct spl_image_info *image, ulong *load_addrp, ulong *lenp,
+		 char **namep);
+
+#endif /* __VBE_ABREC_H */