[ramdisk] add cvitek pre-built ramdisk

Change-Id: Ic7d2046a23358129eaf621b5558984a64fa7361d

ramdisk/initramfs/glibc_riscv64/usr/include/linux/userio.h

@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: LGPL-2.0+ WITH Linux-syscall-note */
+/*
+ * userio: virtual serio device support
+ * Copyright (C) 2015 Red Hat
+ * Copyright (C) 2015 Lyude (Stephen Chandler Paul) <cpaul@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
+ * details.
+ *
+ * This is the public header used for user-space communication with the userio
+ * driver. __attribute__((__packed__)) is used for all structs to keep ABI
+ * compatibility between all architectures.
+ */
+
+#ifndef _USERIO_H
+#define _USERIO_H
+
+#include <linux/types.h>
+
+enum userio_cmd_type {
+	USERIO_CMD_REGISTER = 0,
+	USERIO_CMD_SET_PORT_TYPE = 1,
+	USERIO_CMD_SEND_INTERRUPT = 2
+};
+
+/*
+ * userio Commands
+ * All commands sent to /dev/userio are encoded using this structure. The type
+ * field should contain a USERIO_CMD* value that indicates what kind of command
+ * is being sent to userio. The data field should contain the accompanying
+ * argument for the command, if there is one.
+ */
+struct userio_cmd {
+	__u8 type;
+	__u8 data;
+} __attribute__((__packed__));
+
+#endif /* !_USERIO_H */