1#!/bin/bash
2#
3# Licensed under the terms of the GNU GPL License version 2 or later.
4#
5# Author: Peter Tyser <ptyser@xes-inc.com>
6#
7# U-Boot firmware supports the booting of images in the Flattened Image
8# Tree (FIT) format.  The FIT format uses a device tree structure to
9# describe a kernel image, device tree blob, ramdisk, etc.  This script
10# creates an Image Tree Source (.its file) which can be passed to the
11# 'mkimage' utility to generate an Image Tree Blob (.itb file).  The .itb
12# file can then be booted by U-Boot (or other bootloaders which support
13# FIT images).  See doc/uImage.FIT/howto.txt in U-Boot source code for
14# additional information on FIT images.
15#
16
17usage() {
18	echo "Usage: `basename $0` -A arch -C comp -a addr -e entry" \
19		"-v version -k kernel [-d dtb] -o its_file"
20	echo -e "\t-A ==> set architecture to 'arch'"
21	echo -e "\t-C ==> set compression type 'comp'"
22	echo -e "\t-a ==> set load address to 'addr' (hex)"
23	echo -e "\t-e ==> set entry point to 'entry' (hex)"
24	echo -e "\t-v ==> set kernel version to 'version'"
25	echo -e "\t-k ==> include kernel image 'kernel'"
26	echo -e "\t-d ==> include Device Tree Blob 'dtb'"
27	echo -e "\t-o ==> create output file 'its_file'"
28	exit 1
29}
30
31while getopts ":A:C:a:d:e:k:o:v:" OPTION
32do
33	case $OPTION in
34		A ) ARCH=$OPTARG;;
35		C ) COMPRESS=$OPTARG;;
36		a ) LOAD_ADDR=$OPTARG;;
37		d ) DTB=$OPTARG;;
38		e ) ENTRY_ADDR=$OPTARG;;
39		k ) KERNEL=$OPTARG;;
40		o ) OUTPUT=$OPTARG;;
41		v ) VERSION=$OPTARG;;
42		* ) echo "Invalid option passed to '$0' (options:$@)"
43		usage;;
44	esac
45done
46
47# Make sure user entered all required parameters
48if [ -z "${ARCH}" ] || [ -z "${COMPRESS}" ] || [ -z "${LOAD_ADDR}" ] || \
49	[ -z "${ENTRY_ADDR}" ] || [ -z "${VERSION}" ] || [ -z "${KERNEL}" ] || \
50	[ -z "${OUTPUT}" ]; then
51	usage
52fi
53
54# Create a default, fully populated DTS file
55DATA="/dts-v1/;
56
57/ {
58	description = \"Linux kernel ${VERSION}\";
59	#address-cells = <1>;
60
61	images {
62		kernel@1 {
63			description = \"Linux Kernel ${VERSION}\";
64			data = /incbin/(\"${KERNEL}\");
65			type = \"kernel\";
66			arch = \"${ARCH}\";
67			os = \"linux\";
68			compression = \"${COMPRESS}\";
69			load = <${LOAD_ADDR}>;
70			entry = <${ENTRY_ADDR}>;
71			hash@1 {
72				algo = \"crc32\";
73			};
74			hash@2 {
75				algo = \"sha1\";
76			};
77		};
78
79		fdt@1 { /* start fdt */
80			description = \"Flattened Device Tree blob\";
81			data = /incbin/(\"${DTB}\");
82			type = \"flat_dt\";
83			arch = \"${ARCH}\";
84			compression = \"none\";
85			hash@1 {
86				algo = \"crc32\";
87			};
88			hash@2 {
89				algo = \"sha1\";
90			};
91		}; /* end fdt */
92	};
93
94	configurations {
95		default = \"config@1\";
96		config@1 {
97			description = \"Default Linux kernel\";
98			kernel = \"kernel@1\";
99			fdt = \"fdt@1\";
100		};
101	};
102};"
103
104# Conditionally strip fdt information out of tree
105if [ -z "${DTB}" ]; then
106	DATA=`echo "$DATA" | sed '/start fdt/,/end fdt/d'`
107	DATA=`echo "$DATA" | sed '/fdt/d'`
108fi
109
110# Write .its file to disk
111echo "$DATA" > ${OUTPUT}
112