generate-fat.sh revision 281156 
1#!/bin/sh
2
3# This script generates the dummy FAT filesystem used for the EFI boot
4# blocks. It uses newfs_msdos to generate a template filesystem with the
5# relevant interesting files. These are then found by grep, and the offsets
6# written to a Makefile snippet.
7#
8# Because it requires root, and because it is overkill, we do not
9# do this as part of the normal build. If makefs(8) grows workable FAT
10# support, this should be revisited.
11
12# $FreeBSD: head/sys/boot/efi/boot1/generate-fat.sh 281156 2015-04-06 15:50:20Z andrew $
13
14FAT_SIZE=1600 			#Size in 512-byte blocks of the produced image
15
16BOOT1_SIZE=128k
17
18#
19# Known filenames
20# amd64:   BOOTx64.efi
21# aarch64: BOOTaa64.efi
22# arm:     BOOTarm.efi
23#
24if [ -z "$2" ]; then
25	echo "Usage: $0 arch boot-filename"
26	exit 1
27fi
28
29ARCH=$1
30FILENAME=$2
31
32# Generate 800K FAT image
33OUTPUT_FILE=fat-${ARCH}.tmpl
34
35dd if=/dev/zero of=$OUTPUT_FILE bs=512 count=$FAT_SIZE
36DEVICE=`mdconfig -a -f $OUTPUT_FILE`
37newfs_msdos -F 12 -L EFI $DEVICE
38mkdir stub
39mount -t msdosfs /dev/$DEVICE stub
40
41# Create and bless a directory for the boot loader
42mkdir -p stub/efi/boot
43
44# Make a dummy file for boot1
45echo 'Boot1 START' | dd of=stub/efi/boot/$FILENAME cbs=$BOOT1_SIZE count=1 conv=block
46
47umount stub
48mdconfig -d -u $DEVICE
49rmdir stub
50
51# Locate the offset of the fake file
52BOOT1_OFFSET=$(hd $OUTPUT_FILE | grep 'Boot1 START' | cut -f 1 -d ' ')
53
54# Convert to number of blocks
55BOOT1_OFFSET=$(echo 0x$BOOT1_OFFSET | awk '{printf("%x\n",$1/512);}')
56
57echo '# This file autogenerated by generate-fat.sh - DO NOT EDIT' > Makefile.fat
58echo '# $FreeBSD: head/sys/boot/efi/boot1/generate-fat.sh 281156 2015-04-06 15:50:20Z andrew $' >> Makefile.fat
59echo "BOOT1_OFFSET=0x$BOOT1_OFFSET" >> Makefile.fat
60
61bzip2 $OUTPUT_FILE
62echo 'FAT template boot filesystem created by generate-fat.sh' > $OUTPUT_FILE.bz2.uu
63echo 'DO NOT EDIT' >> $OUTPUT_FILE.bz2.uu
64echo '$FreeBSD: head/sys/boot/efi/boot1/generate-fat.sh 281156 2015-04-06 15:50:20Z andrew $' >> $OUTPUT_FILE.bz2.uu
65
66uuencode $OUTPUT_FILE.bz2 $OUTPUT_FILE.bz2 >> $OUTPUT_FILE.bz2.uu
67rm $OUTPUT_FILE.bz2
68
69