fw: Import tkey-libs fw-2

This is an import of the fw-2 tag of tkey-libs.

We import the entire tkey-libs repo minus dot files into the
tillitis-key1 repo to make it very simple not to make mistakes
regarding which firmware tag depends on which tkey-libs tag,
especially considering locking down with NVCM.

Please see README for information about developing with another
tkey-libs or how to import future tkey-libs.

Since tkey-libs is now a part of the repo we also add tkey-libs to the
clean_fw target.

hw/application_fpga/tkey-libs/include/tkey/proto.h

@@ -0,0 +1,39 @@
+// SPDX-FileCopyrightText: 2022 Tillitis AB <tillitis.se>
+// SPDX-License-Identifier: BSD-2-Clause
+
+#include <stddef.h>
+#include <stdint.h>
+
+#ifndef TKEY_PROTO_H
+#define TKEY_PROTO_H
+
+enum endpoints {
+	DST_HW_IFPGA = 0x00,
+	DST_HW_AFPGA = 0x01,
+	DST_FW = 0x02,
+	DST_SW = 0x03
+};
+
+enum cmdlen {
+	LEN_1,
+	LEN_4,
+	LEN_32,
+	LEN_128
+};
+
+#define CMDLEN_MAXBYTES 128
+
+enum status {
+	STATUS_OK,
+	STATUS_BAD
+};
+
+struct frame_header {
+	uint8_t id;
+	enum endpoints endpoint;
+	size_t len;
+};
+
+uint8_t genhdr(uint8_t id, uint8_t endpoint, uint8_t status, enum cmdlen len);
+int parseframe(uint8_t b, struct frame_header *hdr);
+#endif