src/driver/vpd: Update lib_vpd from upstream

Update lib_vpd.c (only containing vpd_decode.c) to latest version from
https://chromium.googlesource.com/chromiumos/platform/vpd

The called module (vpd.c) has been also corrected for new lib_vpd
types and constants.

BUG=chromium:967209
TEST=select VPD config on kukui; make; boots on at least kukui boards.

Change-Id: I3928e9c43cb87caf93fb44ee10434ce80f0a188a
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/33016
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Joel Kitching <kitching@google.com>

src/drivers/vpd/vpd_decode.h

@@ -0,0 +1,68 @@
+/*
+ * Copyright 2019 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * This is a copy from upstream:
+ * https://chromium.googlesource.com/chromiumos/platform/vpd/+/master/include/lib/vpd_decode.h
+ */
+
+#ifndef __VPD_DECODE_H
+#define __VPD_DECODE_H
+
+#include <stdint.h>
+
+enum {
+	VPD_DECODE_OK = 0,
+	VPD_DECODE_FAIL = 1,
+};
+
+enum {
+	VPD_TYPE_TERMINATOR = 0,
+	VPD_TYPE_STRING,
+	VPD_TYPE_INFO = 0xfe,
+	VPD_TYPE_IMPLICIT_TERMINATOR = 0xff,
+};
+
+/* Callback for vpd_decode_string to invoke. */
+typedef int vpd_decode_callback(
+		const u8 *key, u32 key_len, const u8 *value, u32 value_len,
+		void *arg);
+
+/*
+ * vpd_decode_len
+ *
+ * Given an encoded string, this function extracts the length of content
+ * (either key or value). The *consumed will contain the number of bytes
+ * consumed.
+ *
+ * The input_buf points to the first byte of the input buffer.
+ *
+ * The *consumed starts from 0, which is actually the next byte to be decoded.
+ * It can be non-zero to be used in multiple calls.
+ *
+ * Returns VPD_DECODE_OK on success, otherwise VPD_DECODE_FAIL.
+ */
+int vpd_decode_len(
+		const u32 max_len, const u8 *in, u32 *length, u32 *decoded_len);
+
+/*
+ * vpd_decode_string
+ *
+ * Given the encoded string, this function invokes callback with extracted
+ * (key, value). The *consumed will be plused the number of bytes consumed in
+ * this function.
+ *
+ * The input_buf points to the first byte of the input buffer.
+ *
+ * The *consumed starts from 0, which is actually the next byte to be decoded.
+ * It can be non-zero to be used in multiple calls.
+ *
+ * If one entry is successfully decoded, sends it to callback and returns the
+ * result.
+ */
+int vpd_decode_string(
+		const u32 max_len, const u8 *input_buf, u32 *consumed,
+		vpd_decode_callback callback, void *callback_arg);
+
+#endif  /* __VPD_DECODE_H */