1#!/usr/bin/env bash
2# Helper script to make a SD-card image for the official OP-TEE Raspberry Pi 3
3# build.
4
5set -e
6WORKDIR=""
7
8display_usage() {
9	echo "Usage: $0 [options]"
10	echo "Options:"
11	echo "  -w|--workdir <dir> : The OP-TEE RPI3 working directory"
12	echo "  -h|--help          : Display this help message"
13}
14
15while [[ $# -gt 0 ]]; do
16	key="$1"
17	case $key in
18	-w | --workdir)
19		WORKDIR="$2"
20		shift 2
21		;;
22	-h | --help)
23		display_usage
24		exit 0
25		;;
26	*)
27		echo "Invalid option: $1"
28		display_usage
29		exit 1
30		;;
31	esac
32done
33
34# No point to continue if files/folders we depend on are not existing.
35check_exist() {
36	local dir="$1"
37	if [ ! -e "${dir}" ]; then
38		echo "Folder ${dir} does not exist. Exiting..."
39		exit 1
40	fi
41}
42
43check_exist ${WORKDIR}
44
45IMAGE_FILE=${WORKDIR}/out/rpi3-sdcard.img
46rm -f ${IMAGE_FILE}
47
48################################################################################
49# Configuration
50################################################################################
51OFFSET_KIB=1024
52BOOT_PARTITION_SIZE_MB=64
53# ROOT FS size is read out from the rootfs file created by Buildroot, therefore
54# we don't need to configure that here.
55
56################################################################################
57# Image and partition generation
58################################################################################
59# In bytes, always 512, when creating msdos/MBR images.
60SECTOR_SIZE=512
61
62# 1. Compute the sector size for the offset to the first partition.
63OFFSET_SECTOR_SIZE=$((OFFSET_KIB * 1024 / SECTOR_SIZE))
64echo "OFFSET_SECTOR_SIZE: $((OFFSET_KIB * 1024)) bytes ($((OFFSET_KIB / 1024))MB in ${OFFSET_SECTOR_SIZE} sectors)"
65
66# 2. Calculate the boot partition sizes.
67BOOT_PARTITION_SIZE_KIB=$((BOOT_PARTITION_SIZE_MB * 1024))
68BOOT_PARTITION_SIZE_BYTES=$((BOOT_PARTITION_SIZE_KIB * 1024))
69BOOT_PARTITION_SECTOR_SIZE=$((BOOT_PARTITION_SIZE_BYTES / SECTOR_SIZE))
70echo "BOOT PARTITION SIZE: ${BOOT_PARTITION_SIZE_BYTES} bytes ($(($BOOT_PARTITION_SIZE_BYTES / 1024 / 1024))MB in ${BOOT_PARTITION_SECTOR_SIZE} sectors)"
71
72# 3. Find out the size of the rootfs produced by Buildroot and calculate the
73#    rootfs partition sizes.
74ROOTFS_IMG=${WORKDIR}/out-br/images/rootfs.ext2
75check_exist ${ROOTFS_IMG}
76ROOTFS_SIZE_BYTES=$(stat -c %s ${ROOTFS_IMG})
77ROOTFS_SECTOR_SIZE=$((ROOTFS_SIZE_BYTES / SECTOR_SIZE))
78echo "ROOTFS PARTITION SIZE: ${ROOTFS_SIZE_BYTES} bytes ($((ROOTFS_SIZE_BYTES / 1024 / 1024))MB in ${ROOTFS_SECTOR_SIZE} sectors)"
79
80# 4. Compute the images size, based on the rootfs size, the
81#    desired boot image size and the offset to the first partition.
82IMG_SECTOR_SIZE=$((OFFSET_SECTOR_SIZE + BOOT_PARTITION_SECTOR_SIZE + ROOTFS_SECTOR_SIZE))
83IMG_SIZE_KIB=$((IMG_SECTOR_SIZE * SECTOR_SIZE / 1024))
84echo "TOTAL IMAGE SIZE: ${IMG_SIZE_KIB} bytes ($((IMG_SIZE_KIB / 1024))MB in ${IMG_SECTOR_SIZE} sectors)"
85
86# Create empty disk image
87truncate -s ${IMG_SIZE_KIB}KiB ${IMAGE_FILE}
88
89parted -s ${IMAGE_FILE} unit kiB mklabel msdos
90parted -a optimal ${IMAGE_FILE} unit kiB mkpart primary fat16 ${OFFSET_KIB} ${BOOT_PARTITION_SIZE_KIB}
91parted -a optimal ${IMAGE_FILE} set 1 boot on
92parted -a optimal ${IMAGE_FILE} unit kiB mkpart primary ext4 $((OFFSET_KIB + BOOT_PARTITION_SIZE_KIB)) 100%
93
94# Show some useful information about the image we just created.
95echo ""
96fdisk -l ${IMAGE_FILE}
97
98################################################################################
99# Copy the ext2 partition from Buildroot to the second partition.
100################################################################################
101dd if=${ROOTFS_IMG} of=${IMAGE_FILE} bs=${SECTOR_SIZE} seek=$((OFFSET_SECTOR_SIZE + BOOT_PARTITION_SECTOR_SIZE)) conv=notrunc,fsync
102
103################################################################################
104# Create the boot image and copy it to the boot partition
105################################################################################
106GENIMAGE=${WORKDIR}/out-br/host/bin/genimage
107check_exist ${GENIMAGE}
108
109# Used for a temporary genimage config file.
110RPI3_GENIMAGE_CFG=$(mktemp)
111
112# Used for temporarily storing files when creating the boot vfat image.
113RPI3_GENIMAGE_TMPPATH=$(mktemp -d)
114echo "RPI3_GENIMAGE_CFG: ${RPI3_GENIMAGE_CFG}"
115echo "RPI3_GENIMAGE_TMPPATH: ${RPI3_GENIMAGE_TMPPATH}"
116
117trap "rm -rf ${RPI3_GENIMAGE_CFG} ${RPI3_GENIMAGE_TMPPATH}" EXIT
118
119BOOT_PARTITION_FILES=${WORKDIR}/out/boot
120check_exist ${BOOT_PARTITION_FILES}
121
122# Create the config file for genimage on the fly.
123cat <<EOF >${RPI3_GENIMAGE_CFG}
124image boot.vfat {
125        vfat {
126        }
127
128        size = ${BOOT_PARTITION_SIZE_MB}M
129        mountpoint = "/"
130}
131EOF
132
133# Create the boot.vfat image.
134${GENIMAGE} --rootpath ${BOOT_PARTITION_FILES} --config ${RPI3_GENIMAGE_CFG} --tmppath=${RPI3_GENIMAGE_TMPPATH} --outputpath=${WORKDIR}/out
135
136# Copy the contents of boot.vfat to the boot partition in the image we prepared.
137dd if=${WORKDIR}/out/boot.vfat of=${IMAGE_FILE} bs=${SECTOR_SIZE} seek=${OFFSET_SECTOR_SIZE} conv=notrunc,fsync
138